From patchwork Mon Apr 13 17:04:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486069 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5DA8292C for ; Mon, 13 Apr 2020 17:05:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4071820692 for ; Mon, 13 Apr 2020 17:05:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="jDNKaDAb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732356AbgDMREp (ORCPT ); Mon, 13 Apr 2020 13:04:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51010 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732348AbgDMREm (ORCPT ); Mon, 13 Apr 2020 13:04:42 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE057C0A3BDC for ; Mon, 13 Apr 2020 10:04:42 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id x3so4500730pfp.7 for ; Mon, 13 Apr 2020 10:04:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=EzWGCFkDvwsUypQICHdllbbVZR9HYariWOjwxHmOcJU=; b=jDNKaDAb6kA02CmUEuS9Jz0zodSqrzs+69WDLstboH/H05kSHIitCt9H+ZgZl8EIEA xv06vCxtCckcaBipoQh2rMhI5c1Kg7/lH7n8TcIeS8jqw/E8rvyNY4OM0rF0P+EyPXrt oyFJj0SIde4V3WQiQuvhWr3zWu+/R4TBSTtm0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=EzWGCFkDvwsUypQICHdllbbVZR9HYariWOjwxHmOcJU=; b=ecLz+cfurwp//4gDkCh48vssX0OyyxBaKSb0qsadf3jZ9RM/tXMkZY6PTn7jBCoNuh MH3/Sy4E574pUcL2k8pA5u9RGMGVc8lgkWcN+ZQlCSGCTnEs9/9oLZ8TQsU84d9bAJxu JU59IBDjMwVyw7NXGX29Xt+sd+5EB6jFESngzuJ0Xg9126bIKjOUgLFxOCeQ7uMgaXPY 2Trsw7kqrRmzHkxywTaXIs0nkyKzz/2/6V3e65hH6T9woGVhqbwVlWqtU1NXkyJ5qqDJ lGfcZ4l8OpekeAfBhaZHpxt0mkLnvP4g+oHnbPZ7Rh968dixI09ONfgC8K/QuMj/SfK9 Kq4w== X-Gm-Message-State: AGi0PubEDgo5T1UCKnjKSsq6FusPiCE0fxwp3C+ftaEFvGe//2MZ6got 2CBXwxUDtPTJ4MmP/9HvrfeL3g== X-Google-Smtp-Source: APiQypI5TUQ4L8u/zAcZVFAGzAguSD1tzzaUMhazPvogHBEYfgXzglcZqppteh/SM4UoJOBDZsXxmg== X-Received: by 2002:a62:838b:: with SMTP id h133mr6191256pfe.292.1586797482079; Mon, 13 Apr 2020 10:04:42 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:41 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 01/10] drivers: qcom: rpmh-rsc: Clean code reading/writing TCS regs/cmds Date: Mon, 13 Apr 2020 10:04:06 -0700 Message-Id: <20200413100321.v4.1.I1b754137e8089e46cf33fc2ea270734ec3847ec4@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org This patch makes two changes, both of which should be no-ops: 1. Make read_tcs_reg() / read_tcs_cmd() symmetric to write_tcs_reg() / write_tcs_cmd(). 2. Change the order of operations in the above functions to make it more obvious to me what the math is doing. Specifically first you want to find the right TCS, then the right register, and then multiply by the command ID if necessary. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Add "TCS" in title (Maulik). - Rebased atop v16 ('Invoke rpmh_flush...') series. Changes in v2: None drivers/soc/qcom/rpmh-rsc.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index cc1293cb15a5..91fb5a6d68a2 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -67,28 +67,33 @@ #define CMD_STATUS_ISSUED BIT(8) #define CMD_STATUS_COMPL BIT(16) -static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) +static u32 read_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) { - return readl_relaxed(drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id + + return readl_relaxed(drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg + RSC_DRV_CMD_OFFSET * cmd_id); } +static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id) +{ + return readl_relaxed(drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); +} + static void write_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id, u32 data) { - writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id + + writel_relaxed(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg + RSC_DRV_CMD_OFFSET * cmd_id); } static void write_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, u32 data) { - writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id); + writel_relaxed(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); } static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, u32 data) { - writel(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id); + writel(data, drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg); for (;;) { if (data == readl(drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id)) @@ -100,7 +105,7 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, static bool tcs_is_free(struct rsc_drv *drv, int tcs_id) { return !test_bit(tcs_id, drv->tcs_in_use) && - read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id, 0); + read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id); } static struct tcs_group *get_tcs_of_type(struct rsc_drv *drv, int type) @@ -207,7 +212,7 @@ static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger) * While clearing ensure that the AMC mode trigger is cleared * and then the mode enable is cleared. */ - enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id, 0); + enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id); enable &= ~TCS_AMC_MODE_TRIGGER; write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable); enable &= ~TCS_AMC_MODE_ENABLE; @@ -226,7 +231,7 @@ static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable) { u32 data; - data = read_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0, 0); + data = read_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0); if (enable) data |= BIT(tcs_id); else @@ -245,7 +250,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p) const struct tcs_request *req; struct tcs_cmd *cmd; - irq_status = read_tcs_reg(drv, RSC_DRV_IRQ_STATUS, 0, 0); + irq_status = read_tcs_reg(drv, RSC_DRV_IRQ_STATUS, 0); for_each_set_bit(i, &irq_status, BITS_PER_LONG) { req = get_req_from_tcs(drv, i); @@ -259,7 +264,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p) u32 sts; cmd = &req->cmds[j]; - sts = read_tcs_reg(drv, RSC_DRV_CMD_STATUS, i, j); + sts = read_tcs_cmd(drv, RSC_DRV_CMD_STATUS, i, j); if (!(sts & CMD_STATUS_ISSUED) || ((req->wait_for_compl || cmd->wait) && !(sts & CMD_STATUS_COMPL))) { @@ -313,7 +318,7 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, cmd_msgid |= msg->wait_for_compl ? CMD_MSGID_RESP_REQ : 0; cmd_msgid |= CMD_MSGID_WRITE; - cmd_complete = read_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, 0); + cmd_complete = read_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id); for (i = 0, j = cmd_id; i < msg->num_cmds; i++, j++) { cmd = &msg->cmds[i]; @@ -329,7 +334,7 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, } write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, cmd_complete); - cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0); + cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id); write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, cmd_enable); } @@ -345,10 +350,10 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs, if (tcs_is_free(drv, tcs_id)) continue; - curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0); + curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id); for_each_set_bit(j, &curr_enabled, MAX_CMDS_PER_TCS) { - addr = read_tcs_reg(drv, RSC_DRV_CMD_ADDR, tcs_id, j); + addr = read_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j); for (k = 0; k < msg->num_cmds; k++) { if (addr == msg->cmds[k].addr) return -EBUSY; From patchwork Mon Apr 13 17:04:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486073 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3AD9015AB for ; Mon, 13 Apr 2020 17:06:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1EC48206E9 for ; Mon, 13 Apr 2020 17:06:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="kOanPAx2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732478AbgDMRF6 (ORCPT ); Mon, 13 Apr 2020 13:05:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732351AbgDMREn (ORCPT ); Mon, 13 Apr 2020 13:04:43 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A825BC008749 for ; Mon, 13 Apr 2020 10:04:43 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id d17so4721250pgo.0 for ; Mon, 13 Apr 2020 10:04:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=yQa4rSEyz3ccSDXjPft7iXP/XNiFKyUc3JhnVc0uHhI=; b=kOanPAx2WT+vQFl1nrjQWFWMi/weFrWJhnCi7VqXMiJtMtZP16mCRouNhNTRs39mC4 4KXi7TvuR4B8XqiZ2yKf0Xh1ZyUZLgMIwg7OemA5td/CBdmsmoTimDaHFLvEwp3RibjD FheMpsjQ+vA6ho7LybJrD8cl9Ufb3GGjOVRX0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=yQa4rSEyz3ccSDXjPft7iXP/XNiFKyUc3JhnVc0uHhI=; b=R5xqU1oihvJSQQElKYHW38/alqybcMoL4h6VNLSqVlEow2IXtONCU/e4kpR1zhd1KY o0nGxeuuLgK8EBQF6uhtBrkz95p540miAGElchYMc7ILCpTBHNpp0H0J8S2YxfEVH+UD Kn90N5FxY74FAQp4DGE3ZYDJfm0lharzCTdT7cxbZ2y7PPo0yOIOPCXBY01j61jRFBJR WFdPmf60ZxTErfeYauK5MKDCtXuahQ9KBzBrWtUemrqSPvAxpvTwXTDZRdEBbf5AYQ38 1v7B7ZiMy99khDEdpLKdPOkZ/PGTPXpN3b/mj/ogCPXBiTm7ep7/ffARAsUUoOD6XxPK +jxg== X-Gm-Message-State: AGi0PuaPzPKhvlMb0KuDOLVqmexRBEPzN3uSYefWmsc7XwPlN4qYWx0I bFFsDhVqv+2lEU6rhwogP5PQyA== X-Google-Smtp-Source: APiQypLffysxRK7c+S6N+88TezN7NVI5m12WD316lZEsBbSXW1jfZbneZUmeFqxj7+D1Gl9LArGKvA== X-Received: by 2002:a62:764b:: with SMTP id r72mr350076pfc.207.1586797483162; Mon, 13 Apr 2020 10:04:43 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:42 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 02/10] drivers: qcom: rpmh-rsc: Document the register layout better Date: Mon, 13 Apr 2020 10:04:07 -0700 Message-Id: <20200413100321.v4.2.Iaddc29b72772e6ea381238a0ee85b82d3903e5f2@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Perhaps it's just me, it took a really long time to understand what the register layout of rpmh-rsc was just from the #defines. Let's add a bunch of comments describing which blocks are part of other blocks. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Extra blank line removed (Maulik). - IRQ registers aren't in TCS0 (Maulik). - One space after a period now (Maulik). - Plural of TCS fixed to TCSes following Maulik's example. - Rebased atop v16 ('Invoke rpmh_flush...') series. Changes in v2: - Now prose in comments instead of struct definitions. - Pretty ASCII art from Stephen. drivers/soc/qcom/rpmh-rsc.c | 79 ++++++++++++++++++++++++++++++++++--- 1 file changed, 74 insertions(+), 5 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 91fb5a6d68a2..439a0eadabf1 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -43,14 +43,29 @@ #define DRV_NCPT_MASK 0x1F #define DRV_NCPT_SHIFT 27 -/* Register offsets */ +/* Offsets for common TCS Registers, one bit per TCS */ #define RSC_DRV_IRQ_ENABLE 0x00 #define RSC_DRV_IRQ_STATUS 0x04 -#define RSC_DRV_IRQ_CLEAR 0x08 -#define RSC_DRV_CMD_WAIT_FOR_CMPL 0x10 +#define RSC_DRV_IRQ_CLEAR 0x08 /* w/o; write 1 to clear */ + +/* + * Offsets for per TCS Registers. + * + * TCSes start at 0x10 from tcs_base and are stored one after another. + * Multiply tcs_id by RSC_DRV_TCS_OFFSET to find a given TCS and add one + * of the below to find a register. + */ +#define RSC_DRV_CMD_WAIT_FOR_CMPL 0x10 /* 1 bit per command */ #define RSC_DRV_CONTROL 0x14 -#define RSC_DRV_STATUS 0x18 -#define RSC_DRV_CMD_ENABLE 0x1C +#define RSC_DRV_STATUS 0x18 /* zero if tcs is busy */ +#define RSC_DRV_CMD_ENABLE 0x1C /* 1 bit per command */ + +/* + * Offsets for per command in a TCS. + * + * Commands (up to 16) start at 0x30 in a TCS; multiply command index + * by RSC_DRV_CMD_OFFSET and add one of the below to find a register. + */ #define RSC_DRV_CMD_MSGID 0x30 #define RSC_DRV_CMD_ADDR 0x34 #define RSC_DRV_CMD_DATA 0x38 @@ -67,6 +82,60 @@ #define CMD_STATUS_ISSUED BIT(8) #define CMD_STATUS_COMPL BIT(16) +/* + * Here's a high level overview of how all the registers in RPMH work + * together: + * + * - The main rpmh-rsc address is the base of a register space that can + * be used to find overall configuration of the hardware + * (DRV_PRNT_CHLD_CONFIG). Also found within the rpmh-rsc register + * space are all the TCS blocks. The offset of the TCS blocks is + * specified in the device tree by "qcom,tcs-offset" and used to + * compute tcs_base. + * - TCS blocks come one after another. Type, count, and order are + * specified by the device tree as "qcom,tcs-config". + * - Each TCS block has some registers, then space for up to 16 commands. + * Note that though address space is reserved for 16 commands, fewer + * might be present. See ncpt (num cmds per TCS). + * + * Here's a picture: + * + * +---------------------------------------------------+ + * |RSC | + * | ctrl | + * | | + * | Drvs: | + * | +-----------------------------------------------+ | + * | |DRV0 | | + * | | ctrl/config | | + * | | IRQ | | + * | | | | + * | | TCSes: | | + * | | +------------------------------------------+ | | + * | | |TCS0 | | | | | | | | | | | | | | | + * | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | | + * | | | | | | | | | | | | | | | | | | + * | | +------------------------------------------+ | | + * | | +------------------------------------------+ | | + * | | |TCS1 | | | | | | | | | | | | | | | + * | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | | + * | | | | | | | | | | | | | | | | | | + * | | +------------------------------------------+ | | + * | | +------------------------------------------+ | | + * | | |TCS2 | | | | | | | | | | | | | | | + * | | | ctrl | 0| 1| 2| 3| 4| 5| .| .| .| .|14|15| | | + * | | | | | | | | | | | | | | | | | | + * | | +------------------------------------------+ | | + * | | ...... | | + * | +-----------------------------------------------+ | + * | +-----------------------------------------------+ | + * | |DRV1 | | + * | | (same as DRV0) | | + * | +-----------------------------------------------+ | + * | ...... | + * +---------------------------------------------------+ + */ + static u32 read_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id) { return readl_relaxed(drv->tcs_base + RSC_DRV_TCS_OFFSET * tcs_id + reg + From patchwork Mon Apr 13 17:04:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486071 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9433592C for ; Mon, 13 Apr 2020 17:05:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B43E20692 for ; Mon, 13 Apr 2020 17:05:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="PAWFK6hy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732476AbgDMRF6 (ORCPT ); Mon, 13 Apr 2020 13:05:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732353AbgDMREo (ORCPT ); Mon, 13 Apr 2020 13:04:44 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C38AEC008769 for ; Mon, 13 Apr 2020 10:04:44 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id r20so3091194pfh.9 for ; Mon, 13 Apr 2020 10:04:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tzydfxNpFyQ37xWSVbnHjBlq3rGsJWK4NEoeBYdHSGE=; b=PAWFK6hyUJ2FMAEd5m1yBDd9/wMCyVdsdeGo/pb+0IWz1bN+ACGpK6RiQ1OjnlHCDW wg+3p3F/+xGKw5jAdn2vh9hDmUFAgpGqGeWKPpPAQ0hLNihu9ykfgagxoTXeFWXyFqrK JZiT2I/pmITimBBh5qz/X06OMc+Un5+ZZUTMg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tzydfxNpFyQ37xWSVbnHjBlq3rGsJWK4NEoeBYdHSGE=; b=UOyzZBCtNnQ3y6gxDjdv0T+uGcc15d+dFtIlWpph8yY34fWBD0wOtJJkJ9xzrgwuGI uCTyFl4Rg8lbM6NVShDxLVAcLd8l7mNeCBN38OsuN/DwZgBoNp2E6kjvcGz55WOt695V rXPqdcfMP3tnK9lnFXKXU178fPNPsEb2Y9l/BqEUPpnHpqfMKcWv0dc0XkCdPTJwbKOm tzr69c0fAJOGT30Gt3jhB8i02AVdR8UY46+/Cn44aqxd72jmBEQ5O6b0xyZ1u/YQD4aP u1v5Y3PxMIslU8Sq1oDexQymYvfb3vnAoeLVwafOWRTU27lalaLu1qgchlBCUCz9bNdv 4E/A== X-Gm-Message-State: AGi0PuYf6e/Z+OGMnD75KcYQ6MjEmwKqSDNlV9l5mLXpExrdBuzowy/o BEOWsvwjfmFDx1LoVNQNPMaOHA== X-Google-Smtp-Source: APiQypIjV881eF9Wj1nHGTP+Z56sK4PbX5r1Hs7Wq0wemPIScGv1u2J9wLQNTzsPos6dMrVHgXhSWw== X-Received: by 2002:aa7:94b5:: with SMTP id a21mr18448612pfl.290.1586797484336; Mon, 13 Apr 2020 10:04:44 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:43 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 03/10] drivers: qcom: rpmh-rsc: Fold tcs_ctrl_write() into its single caller Date: Mon, 13 Apr 2020 10:04:08 -0700 Message-Id: <20200413100321.v4.3.Ie88ce5ccfc0c6055903ccca5286ae28ed3b85ed3@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org I was trying to write documentation for the functions in rpmh-rsc and I got to tcs_ctrl_write(). The documentation for the function would have been: "This is the core of rpmh_rsc_write_ctrl_data(); all the caller does is error-check and then call this". Having the error checks in a separate function doesn't help for anything since: - There are no other callers that need to bypass the error checks. - It's less documenting. When I read tcs_ctrl_write() I kept wondering if I need to handle cases other than ACTIVE_ONLY or cases with more commands than could fit in a TCS. This is obvious when the error checks and code are together. - The function just isn't that long, so there's no problem understanding the combined function. Things were even more confusing because the two functions names didn't make obvious (at least to me) their relationship. Simplify by folding one function into the other. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: None Changes in v2: None drivers/soc/qcom/rpmh-rsc.c | 39 ++++++++++++++++--------------------- 1 file changed, 17 insertions(+), 22 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 439a0eadabf1..d9177324c6a2 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -587,27 +587,6 @@ static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg, return 0; } -static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg) -{ - struct tcs_group *tcs; - int tcs_id = 0, cmd_id = 0; - unsigned long flags; - int ret; - - tcs = get_tcs_for_msg(drv, msg); - if (IS_ERR(tcs)) - return PTR_ERR(tcs); - - spin_lock_irqsave(&tcs->lock, flags); - /* find the TCS id and the command in the TCS to write to */ - ret = find_slots(tcs, msg, &tcs_id, &cmd_id); - if (!ret) - __tcs_buffer_write(drv, tcs_id, cmd_id, msg); - spin_unlock_irqrestore(&tcs->lock, flags); - - return ret; -} - /** * rpmh_rsc_write_ctrl_data: Write request to the controller * @@ -618,6 +597,11 @@ static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg) */ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) { + struct tcs_group *tcs; + int tcs_id = 0, cmd_id = 0; + unsigned long flags; + int ret; + if (!msg || !msg->cmds || !msg->num_cmds || msg->num_cmds > MAX_RPMH_PAYLOAD) { pr_err("Payload error\n"); @@ -628,7 +612,18 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) if (msg->state == RPMH_ACTIVE_ONLY_STATE) return -EINVAL; - return tcs_ctrl_write(drv, msg); + tcs = get_tcs_for_msg(drv, msg); + if (IS_ERR(tcs)) + return PTR_ERR(tcs); + + spin_lock_irqsave(&tcs->lock, flags); + /* find the TCS id and the command in the TCS to write to */ + ret = find_slots(tcs, msg, &tcs_id, &cmd_id); + if (!ret) + __tcs_buffer_write(drv, tcs_id, cmd_id, msg); + spin_unlock_irqrestore(&tcs->lock, flags); + + return ret; } /** From patchwork Mon Apr 13 17:04:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486067 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C770D14B4 for ; Mon, 13 Apr 2020 17:05:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD69020692 for ; Mon, 13 Apr 2020 17:05:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="GgM06dNn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732474AbgDMRFy (ORCPT ); Mon, 13 Apr 2020 13:05:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732359AbgDMREq (ORCPT ); Mon, 13 Apr 2020 13:04:46 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4122AC0A3BDC for ; Mon, 13 Apr 2020 10:04:46 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id k191so4692167pgc.13 for ; Mon, 13 Apr 2020 10:04:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=G1C9cYygROwcdB+bdyaotBkigEG8W7Qz/WT7Sqd2jQY=; b=GgM06dNnb/HF2lWUMTa/Sh7aCApPmK5Isbt8fzX1llhZQrcEZjo3RQNAdtewm+exPj MM+dXbeAPsGRAiXGqy+VD+1Oc0vl7GHQQYAn5FsOUX5BEXLn3lNMpG5GmSQz++Mj0jWH DR9QuUup+GLxJWi7nrGhW191Jwoc/BX/U4gaI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=G1C9cYygROwcdB+bdyaotBkigEG8W7Qz/WT7Sqd2jQY=; b=pAS5Qjo2elqKDhC2UGOrjVFaswpI2xtdbdszjYYBiI+EuMy5KQNe3n/uDbGcP7xBMt 3CXhZBR6Uzk2G+cepAGIMXaO2FGDgYQhbSe/YuzICgXzdA2uiGdulRBxoradxkS7kO48 HePIeZ0WlWr/gwey52Dj2nUiYRju0sR232ZVH8qK/FezkrWIggON0nll4rD3DEX4G+W9 3PeB7TVhBe/g6PakDjEvRGfGSmzbHwAV5c4bYltd3IHhxccexvsZYRQMJXjeC/XqGyAQ 2C6l41XxgiTtCQAaN4s/f4cMDBEiwbCy+wOdibJleI3EmgmrLltu5/2MX4W3BANc8ktJ U3yA== X-Gm-Message-State: AGi0PuYpgLn/JEd9HBLpTYT7zKrt1lRDpbDE5s64OHXOngudwYVfvPa0 Cz3wwRN8R++1qJZVk1bW9USyzw== X-Google-Smtp-Source: APiQypJsdNI69RZEIChzgAH/1VncKohdU4FrKkW87ZmmJ/KYPQvWwjDZUnP8L1l80kg+O3d+STeteg== X-Received: by 2002:aa7:9703:: with SMTP id a3mr11361283pfg.318.1586797485782; Mon, 13 Apr 2020 10:04:45 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:45 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 04/10] drivers: qcom: rpmh-rsc: Remove get_tcs_of_type() abstraction Date: Mon, 13 Apr 2020 10:04:09 -0700 Message-Id: <20200413100321.v4.4.Ia348ade7c6ed1d0d952ff2245bc854e5834c8d9a@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The get_tcs_of_type() function doesn't provide any value. It's not conceptually difficult to access a value in an array, even if that value is in a structure and we want a pointer to the value. Having the function in there makes me feel like it's doing something fancier like looping or searching. Remove it. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Rebased atop v16 ('Invoke rpmh_flush...') series. Changes in v2: None drivers/soc/qcom/rpmh-rsc.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index d9177324c6a2..d0c187c17ce1 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -177,17 +177,10 @@ static bool tcs_is_free(struct rsc_drv *drv, int tcs_id) read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id); } -static struct tcs_group *get_tcs_of_type(struct rsc_drv *drv, int type) -{ - return &drv->tcs[type]; -} - static int tcs_invalidate(struct rsc_drv *drv, int type) { int m; - struct tcs_group *tcs; - - tcs = get_tcs_of_type(drv, type); + struct tcs_group *tcs = &drv->tcs[type]; spin_lock(&tcs->lock); if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) { @@ -250,9 +243,9 @@ static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv, * dedicated TCS for active state use, then re-purpose a wake TCS to * send active votes. */ - tcs = get_tcs_of_type(drv, type); + tcs = &drv->tcs[type]; if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs) - tcs = get_tcs_of_type(drv, WAKE_TCS); + tcs = &drv->tcs[WAKE_TCS]; return tcs; } @@ -643,7 +636,7 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv) { int m; - struct tcs_group *tcs = get_tcs_of_type(drv, ACTIVE_TCS); + struct tcs_group *tcs = &drv->tcs[ACTIVE_TCS]; /* * If we made an active request on a RSC that does not have a @@ -655,7 +648,7 @@ static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv) * lock before checking tcs_is_free(). */ if (!tcs->num_tcs) - tcs = get_tcs_of_type(drv, WAKE_TCS); + tcs = &drv->tcs[WAKE_TCS]; for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) { if (!tcs_is_free(drv, m)) From patchwork Mon Apr 13 17:04:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486065 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3301D92C for ; Mon, 13 Apr 2020 17:05:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14048206E9 for ; Mon, 13 Apr 2020 17:05:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="RPltUmCx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732371AbgDMRFo (ORCPT ); Mon, 13 Apr 2020 13:05:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732367AbgDMREs (ORCPT ); Mon, 13 Apr 2020 13:04:48 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6932EC008769 for ; Mon, 13 Apr 2020 10:04:47 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id q16so3306646pje.1 for ; Mon, 13 Apr 2020 10:04:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=H5jzm0jKocH6kBLkIZiIivBDeHVXIyNk3YV4qC7ABfQ=; b=RPltUmCxB2JvpwDlp7cExzjz0QjR6FfUIWjdeAwnV7bMwwIgtyOD+U7eSrbmSeGgdv wM22kOEgpnY2JWYjGQ+DvuT2GcntM46V/GM4e0agI2ecUA63gFh/VB14GGmLEtsFd9bl ZUll9fWxmXkY8Cw9oZz84LqxTfspis9PMEdVI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=H5jzm0jKocH6kBLkIZiIivBDeHVXIyNk3YV4qC7ABfQ=; b=UD4MsajqfPXTsDvf6r/eR0nkOgt8b5gugxSSFJNuY7EulMUwn+qKCbdbOUSpaQ9OT0 H/x+udqHysPs/DwfUM/o4qG1fJk84fZlabt9vrYl1iL2G2ZUxoof8FEe2ff5FmPXkd0l VXLvq4HzhEaokK4KYo4IieUCkEVlkaOo4XGFnMCuEMFSi4BY9pdYZLVsGCMkbLED1383 JMshTEmFhlRVtUv6/nSJzt8DcMi6kreUbvKtCeN1F8HDDCQHCw+OlbUNC+WnMWYvAdS2 ZTWgtONdoT0Knp95tBTnsPSJkLStyY4kkzPzkqpVQ81D6vGZ9Pkq/tuvzrQk7itYqGD+ MFCA== X-Gm-Message-State: AGi0PuaVZKSsGjy27zKeZmIwKTISweO5BmsmohmfxggidTf8mzTNTlPS YAD1RJbwFdzIM+w+ErcZeUiXFw== X-Google-Smtp-Source: APiQypLw7Ub9qcbTy6hWSopaNYIaGu+ANobNFlCAGog7pxke7XfEbrS+muVCox/Qo6VUHrpDppPevg== X-Received: by 2002:a17:90a:9b17:: with SMTP id f23mr22618281pjp.118.1586797486900; Mon, 13 Apr 2020 10:04:46 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:46 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 05/10] drivers: qcom: rpmh-rsc: Kill cmd_cache and find_match() with fire Date: Mon, 13 Apr 2020 10:04:10 -0700 Message-Id: <20200413100321.v4.5.I6d3d0a3ec810dc72ff1df3cbf97deefdcdeb8eef@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The "cmd_cache" in RPMH wasn't terribly sensible. Specifically: - The current code doesn't realy detect "conflicts" properly any case where the sequence being checked has more than one entry. One simple way to see this in the current code is that if cmd[0].addr isn't found that cmd[1].addr is never checked. - The code attempted to use the "cmd_cache" to update an existing message in a sleep/wake TCS with new data. The goal appeared to be to update part of a TCS while leaving the rest of the TCS alone. We never actually do this. We always fully invalidate and re-write everything. - If/when we try to optimize things to not fully invalidate / re-write every time we update the TCSes we'll need to think it through very carefully. Specifically requirement of find_match() that the new sequence of addrs must match exactly the old sequence of addrs seems inflexible. It's also not documented in rpmh_write() and rpmh_write_batch(). In any case, if we do decide to require updates to keep the exact same sequence and length then presumably the API and data structures should be updated to understand groups more properly. The current algorithm doesn't really keep track of the length of the old sequence and there are several boundary-condition bugs because of that. Said another way: if we decide to do something like this in the future we should start from scratch and thus find_match() isn't useful to keep around. This patch isn't quite a no-op. Specifically: - It should be a slight performance boost of not searching through so many arrays. - The old code would have done something useful in one case: it would allow someone calling rpmh_write() to override the data that came from rpmh_write_batch(). I don't believe that actually happens in reality. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Kill find_match moves from patch #9 to patch #5 (Maulik). - Rewrote commit message to adjust for patch order. Changes in v2: - Got rid of useless "if (x) continue" at end of for loop. drivers/soc/qcom/rpmh-internal.h | 2 -- drivers/soc/qcom/rpmh-rsc.c | 47 -------------------------------- 2 files changed, 49 deletions(-) diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index e9a90cb7773e..6a6d776ccca9 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -30,7 +30,6 @@ struct rsc_drv; * @ncpt: number of commands in each TCS * @lock: lock for synchronizing this TCS writes * @req: requests that are sent from the TCS - * @cmd_cache: flattened cache of cmds in sleep/wake TCS * @slots: indicates which of @cmd_addr are occupied */ struct tcs_group { @@ -42,7 +41,6 @@ struct tcs_group { int ncpt; spinlock_t lock; const struct tcs_request *req[MAX_TCS_PER_TYPE]; - u32 *cmd_cache; DECLARE_BITMAP(slots, MAX_TCS_SLOTS); }; diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index d0c187c17ce1..c9e5cddbc099 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -522,42 +522,12 @@ int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) return ret; } -static int find_match(const struct tcs_group *tcs, const struct tcs_cmd *cmd, - int len) -{ - int i, j; - - /* Check for already cached commands */ - for_each_set_bit(i, tcs->slots, MAX_TCS_SLOTS) { - if (tcs->cmd_cache[i] != cmd[0].addr) - continue; - if (i + len >= tcs->num_tcs * tcs->ncpt) - goto seq_err; - for (j = 0; j < len; j++) { - if (tcs->cmd_cache[i + j] != cmd[j].addr) - goto seq_err; - } - return i; - } - - return -ENODATA; - -seq_err: - WARN(1, "Message does not match previous sequence.\n"); - return -EINVAL; -} - static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg, int *tcs_id, int *cmd_id) { int slot, offset; int i = 0; - /* Find if we already have the msg in our TCS */ - slot = find_match(tcs, msg->cmds, msg->num_cmds); - if (slot >= 0) - goto copy_data; - /* Do over, until we can fit the full payload in a TCS */ do { slot = bitmap_find_next_zero_area(tcs->slots, MAX_TCS_SLOTS, @@ -567,11 +537,7 @@ static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg, i += tcs->ncpt; } while (slot + msg->num_cmds - 1 >= i); -copy_data: bitmap_set(tcs->slots, slot, msg->num_cmds); - /* Copy the addresses of the resources over to the slots */ - for (i = 0; i < msg->num_cmds; i++) - tcs->cmd_cache[slot + i] = msg->cmds[i].addr; offset = slot / tcs->ncpt; *tcs_id = offset + tcs->offset; @@ -762,19 +728,6 @@ static int rpmh_probe_tcs_config(struct platform_device *pdev, tcs->mask = ((1 << tcs->num_tcs) - 1) << st; tcs->offset = st; st += tcs->num_tcs; - - /* - * Allocate memory to cache sleep and wake requests to - * avoid reading TCS register memory. - */ - if (tcs->type == ACTIVE_TCS) - continue; - - tcs->cmd_cache = devm_kcalloc(&pdev->dev, - tcs->num_tcs * ncpt, sizeof(u32), - GFP_KERNEL); - if (!tcs->cmd_cache) - return -ENOMEM; } drv->num_tcs = st; From patchwork Mon Apr 13 17:04:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486063 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C350414B4 for ; Mon, 13 Apr 2020 17:05:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9061120692 for ; Mon, 13 Apr 2020 17:05:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="apG9JsfY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732457AbgDMRFo (ORCPT ); Mon, 13 Apr 2020 13:05:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51044 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732371AbgDMREt (ORCPT ); Mon, 13 Apr 2020 13:04:49 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EB3EC00860A for ; Mon, 13 Apr 2020 10:04:49 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id nu11so4035557pjb.1 for ; Mon, 13 Apr 2020 10:04:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=fVUhSo4hNqQwQBbd5xElXyQ296KGFGG1bP3GUabXMSo=; b=apG9JsfYtx78Uw1JwH+1vqbsgjO963arAqSar4baMQ9XeU5KzihDGOyVOCN5FaDSQY 7DvIWsRTHuBxmmXPR9aKVCr8HkVdPfaijYDQqoBDrr/3zqRWkhKSiqAPNhR0GFNv+9Zp bLsqYk2UlylwXMMfMYIFQQSGjXGv2kQtGXkNc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=fVUhSo4hNqQwQBbd5xElXyQ296KGFGG1bP3GUabXMSo=; b=U4hlXgL/6oebNA1MfgBsDFgExQPvJQndjwWWRmHdBgFf0vkmwV7xcGFMvNCJxT/PdR Sb2HRPoC8C7tzGSlwsNDA7GbK4vi4F4StPX6vqB1YEGwfar+RqIWFFd7xVcx03LDMixo L8+SGd352gqYIizu/why7q2yLehOfgrd+ozh1MjbQsmbiaYXo4uiURQxBTCoaOY37JBd A599Uj94WAszmAe31s757qfvPQY8ra2fJV4LrIF5xe0D3zuF+HumwOOpQ40tySc024mV laQLiG99cbgtKMNw6ulKzsxIlx/I1E/ZQl/CKy5Gif67d6YungTpdFNqDDhyryG4JZEQ KSCw== X-Gm-Message-State: AGi0PubU6YT8oU3KNNvHPsBbemKpMGCpLhgn0GWWOvw/VyJK4nbhntvk ueT4cyEXGQq5qyfo7rKsW2Sp1g== X-Google-Smtp-Source: APiQypLdPmRwauGHE7PP1bbRJdDBv/+7vOAY8V5tPZzlo++VR4v1n93nOi9gb9pIuyGFjShU2t5eLw== X-Received: by 2002:a17:90a:2149:: with SMTP id a67mr13979537pje.43.1586797488435; Mon, 13 Apr 2020 10:04:48 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:47 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 06/10] drivers: qcom: rpmh-rsc: A lot of comments Date: Mon, 13 Apr 2020 10:04:11 -0700 Message-Id: <20200413100321.v4.6.I52653eb85d7dc8981ee0dafcd0b6cc0f273e9425@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org I've been pouring through the rpmh-rsc code and trying to understand it. Document everything to the best of my ability. All documentation here is strictly from code analysis--no actual knowledge of the hardware was used. If something is wrong in here I either misunderstood the code, had a typo, or the code has a bug in it leading to my incorrect understanding. In a few places here I have documented things that don't make tons of sense. A future patch will try to address this. While this means I'm adding comments / todos and then later fixing them in the series, it seemed more urgent to get things documented first so that people could understand the later patches. Any comments I adjusted I also tried to make match kernel-doc better. Specifically: - kernel-doc says do not leave a blank line between the function description and the arguments - kernel-doc examples always have things starting w/ a capital and ending with a period. This should be a no-op. It's just comment changes. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Adjusted comments for rpmh_rsc_write_ctrl_data(). - Comments for new enable_tcs_irq() function. - Comments for new rpmh_rsc_cpu_pm_callback() function. - Mention in message that I also fixed up kernel-doc stuff. - Moved comments patch after ("Kill cmd_cache and find_match..."). - One space after a period now (Maulik). - Plural of TCS fixed to TCSes following Maulik's example. - Re-added comment in tcs_write() about checking for same address. - Rebased atop v16 ('Invoke rpmh_flush...') series. - __tcs_set_trigger() comments adjusted now that it can set or unset. - get_tcs_for_msg() documents why it's safe to borrow the wake TCS. - get_tcs_for_msg() no longer returns -EAGAIN. Changes in v2: - Document bug of tcs_write() not handling -EAGAIN. - Document get_tcs_for_msg() => -EAGAIN only for ACTIVE_ONLY. - Document locks for updating "tcs_in_use" more. - Document tcs_is_free() without drv->lock OK for tcs_invalidate(). - Document that rpmh_rsc_send_data() can be an implicit invalidate. - Document two get_tcs_for_msg() issues if zero-active TCS. - Fixed documentation of "tcs" param in find_slots(). - More clear that active-only xfers can happen on wake TCS sometimes. - Reword tcs_write() doc a bit. drivers/soc/qcom/rpmh-internal.h | 62 ++++++--- drivers/soc/qcom/rpmh-rsc.c | 221 ++++++++++++++++++++++++++++--- 2 files changed, 246 insertions(+), 37 deletions(-) diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index 6a6d776ccca9..f06350cbc9a2 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -22,15 +22,24 @@ struct rsc_drv; * struct tcs_group: group of Trigger Command Sets (TCS) to send state requests * to the controller * - * @drv: the controller - * @type: type of the TCS in this group - active, sleep, wake - * @mask: mask of the TCSes relative to all the TCSes in the RSC - * @offset: start of the TCS group relative to the TCSes in the RSC - * @num_tcs: number of TCSes in this type - * @ncpt: number of commands in each TCS - * @lock: lock for synchronizing this TCS writes - * @req: requests that are sent from the TCS - * @slots: indicates which of @cmd_addr are occupied + * @drv: The controller. + * @type: Type of the TCS in this group - active, sleep, wake. + * @mask: Mask of the TCSes relative to all the TCSes in the RSC. + * @offset: Start of the TCS group relative to the TCSes in the RSC. + * @num_tcs: Number of TCSes in this type. + * @ncpt: Number of commands in each TCS. + * @lock: Lock for synchronizing this TCS writes. + * @req: Requests that are sent from the TCS; only used for ACTIVE_ONLY + * transfers (could be on a wake/sleep TCS if we are borrowing for + * an ACTIVE_ONLY transfer). + * Start: grab drv->lock, set req, set tcs_in_use, drop drv->lock, + * trigger + * End: get irq, access req, + * grab drv->lock, clear tcs_in_use, drop drv->lock + * @slots: Indicates which of @cmd_addr are occupied; only used for + * SLEEP / WAKE TCSs. Things are tightly packed in the + * case that (ncpt < MAX_CMDS_PER_TCS). That is if ncpt = 2 and + * MAX_CMDS_PER_TCS = 16 then bit[2] = the first bit in 2nd TCS. */ struct tcs_group { struct rsc_drv *drv; @@ -82,19 +91,28 @@ struct rpmh_ctrlr { * struct rsc_drv: the Direct Resource Voter (DRV) of the * Resource State Coordinator controller (RSC) * - * @name: Controller identifier - * @tcs_base: Start address of the TCS registers in this controller - * @id: Instance id in the controller (Direct Resource Voter) - * @num_tcs: Number of TCSes in this DRV - * @rsc_pm: CPU PM notifier for controller - * Used when solver mode is not present - * @cpus_entered_pm: CPU mask for cpus in idle power collapse - * Used when solver mode is not present - * @tcs: TCS groups - * @tcs_in_use: S/W state of the TCS - * @lock: Synchronize state of the controller - * @pm_lock: Synchronize during PM notifications - * Used when solver mode is not present + * @name: Controller identifier. + * @tcs_base: Start address of the TCS registers in this controller. + * @id: Instance id in the controller (Direct Resource Voter). + * @num_tcs: Number of TCSes in this DRV. + * @rsc_pm: CPU PM notifier for controller. + * Used when solver mode is not present. + * @cpus_entered_pm: CPU mask for cpus in idle power collapse. + * Used when solver mode is not present. + * @tcs: TCS groups. + * @tcs_in_use: S/W state of the TCS; only set for ACTIVE_ONLY + * transfers, but might show a sleep/wake TCS in use if + * it was borrowed for an active_only transfer. You + * must hold both the lock in this struct and the + * tcs_lock for the TCS in order to mark a TCS as + * in-use, but you only need the lock in this structure + * (aka the drv->lock) to mark one freed. + * @lock: Synchronize state of the controller. If you will be + * grabbing this lock and a tcs_lock at the same time, + * grab the tcs_lock first so we always have a + * consistent lock ordering. + * @pm_lock: Synchronize during PM notifications. + * Used when solver mode is not present. * @client: Handle to the DRV's client. */ struct rsc_drv { diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index c9e5cddbc099..f0a7ada0c16f 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -171,12 +171,38 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, } } +/** + * tcs_is_free() - Return if a TCS is totally free. + * @drv: The RSC controller. + * @tcs_id: The global ID of this TCS. + * + * Returns true if nobody has claimed this TCS (by setting tcs_in_use). + * If the TCS looks free, checks that the hardware agrees. + * + * Must be called with the drv->lock held or the tcs_lock for the TCS being + * tested. If only the tcs_lock is held then it is possible that this + * function will return that a tcs is still busy when it has been recently + * been freed but it will never return free when a TCS is actually in use. + * + * Return: true if the given TCS is free. + */ static bool tcs_is_free(struct rsc_drv *drv, int tcs_id) { return !test_bit(tcs_id, drv->tcs_in_use) && read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id); } +/** + * tcs_invalidate() - Invalidate all TCSes of the given type (sleep or wake). + * @drv: The RSC controller. + * @type: SLEEP_TCS or WAKE_TCS + * + * This will clear the "slots" variable of the given tcs_group and also + * tell the hardware to forget about all entries. + * + * Return: 0 if no problem, or -EAGAIN if the caller should try again in a + * bit. Caller should make sure to enable interrupts between tries. + */ static int tcs_invalidate(struct rsc_drv *drv, int type) { int m; @@ -203,9 +229,11 @@ static int tcs_invalidate(struct rsc_drv *drv, int type) } /** - * rpmh_rsc_invalidate - Invalidate sleep and wake TCSes + * rpmh_rsc_invalidate() - Invalidate sleep and wake TCSes. + * @drv: The RSC controller. * - * @drv: the RSC controller + * Return: 0 if no problem, or -EAGAIN if the caller should try again in a + * bit. Caller should make sure to enable interrupts between tries. */ int rpmh_rsc_invalidate(struct rsc_drv *drv) { @@ -218,6 +246,18 @@ int rpmh_rsc_invalidate(struct rsc_drv *drv) return ret; } +/** + * get_tcs_for_msg() - Get the tcs_group used to send the given message. + * @drv: The RSC controller. + * @msg: The message we want to send. + * + * This is normally pretty straightforward except if we are trying to send + * an ACTIVE_ONLY message but don't have any active_only TCSes. + * + * Called without drv->lock held and with no tcs_lock locks held. + * + * Return: A pointer to a tcs_group or an ERR_PTR. + */ static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv, const struct tcs_request *msg) { @@ -241,7 +281,9 @@ static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv, /* * If we are making an active request on a RSC that does not have a * dedicated TCS for active state use, then re-purpose a wake TCS to - * send active votes. + * send active votes. This is safe because we ensure any active-only + * transfers have finished before we use it (maybe by running from + * the last CPU in PM code). */ tcs = &drv->tcs[type]; if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs) @@ -250,6 +292,22 @@ static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv, return tcs; } +/** + * get_req_from_tcs() - Get a stashed request that was xfering on the given TCS. + * @drv: The RSC controller. + * @tcs_id: The global ID of this TCS. + * + * For ACTIVE_ONLY transfers we want to call back into the client when the + * transfer finishes. To do this we need the "request" that the client + * originally provided us. This function grabs the request that we stashed + * when we started the transfer. + * + * This only makes sense for ACTIVE_ONLY transfers since those are the only + * ones we track sending (the only ones we enable interrupts for and the only + * ones we call back to the client for). + * + * Return: The stashed request. + */ static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv, int tcs_id) { @@ -265,6 +323,23 @@ static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv, return NULL; } +/** + * __tcs_set_trigger() - Start xfer on a TCS or unset trigger on a borrowed TCS + * @drv: The controller. + * @tcs_id: The global ID of this TCS. + * @trigger: If true then untrigger/retrigger. If false then just untrigger. + * + * In the normal case we only ever call with "trigger=true" to start a + * transfer. That will un-trigger/disable the TCS from the last transfer + * then trigger/enable for this transfer. + * + * If we borrowed a wake TCS for an active-only transfer we'll also call + * this function with "trigger=false" to just do the un-trigger/disable + * before using the TCS for wake purposes again. + * + * Note that the AP is only in charge of triggering active-only transfers. + * The AP never triggers sleep/wake values using this function. + */ static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger) { u32 enable; @@ -289,6 +364,15 @@ static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger) } } +/** + * enable_tcs_irq() - Enable or disable interrupts on the given TCS. + * @drv: The controller. + * @tcs_id: The global ID of this TCS. + * @enable: If true then enable; if false then disable + * + * We only ever call this when we borrow a wake TCS for an active-only + * transfer. For active-only TCSes interrupts are always left enabled. + */ static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable) { u32 data; @@ -302,7 +386,14 @@ static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable) } /** - * tcs_tx_done: TX Done interrupt handler + * tcs_tx_done() - TX Done interrupt handler. + * @irq: The IRQ number (ignored). + * @p: Pointer to "struct rsc_drv". + * + * Called for ACTIVE_ONLY transfers (those are the only ones we enable the + * IRQ for) when a transfer is done. + * + * Return: IRQ_HANDLED */ static irqreturn_t tcs_tx_done(int irq, void *p) { @@ -367,6 +458,16 @@ static irqreturn_t tcs_tx_done(int irq, void *p) return IRQ_HANDLED; } +/** + * __tcs_buffer_write() - Write to TCS hardware from a request; don't trigger. + * @drv: The controller. + * @tcs_id: The global ID of this TCS. + * @cmd_id: The index within the TCS to start writing. + * @msg: The message we want to send, which will contain several addr/data + * pairs to program (but few enough that they all fit in one TCS). + * + * This is used for all types of transfers (active, sleep, and wake). + */ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, const struct tcs_request *msg) { @@ -400,6 +501,26 @@ static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id, write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, cmd_enable); } +/** + * check_for_req_inflight() - Look to see if conflicting cmds are in flight. + * @drv: The controller. + * @tcs: A pointer to the tcs_group used for ACTIVE_ONLY transfers. + * @msg: The message we want to send, which will contain several addr/data + * pairs to program (but few enough that they all fit in one TCS). + * + * This will walk through the TCSes in the group and check if any of them + * appear to be sending to addresses referenced in the message. If it finds + * one it'll return -EBUSY. + * + * Only for use for active-only transfers. + * + * Must be called with the drv->lock held since that protects tcs_in_use. + * + * Return: 0 if nothing in flight or -EBUSY if we should try again later. + * The caller must re-enable interrupts between tries since that's + * the only way tcs_is_free() will ever return true and the only way + * RSC_DRV_CMD_ENABLE will ever be cleared. + */ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs, const struct tcs_request *msg) { @@ -426,6 +547,15 @@ static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs, return 0; } +/** + * find_free_tcs() - Find free tcs in the given tcs_group; only for active. + * @tcs: A pointer to the active-only tcs_group (or the wake tcs_group if + * we borrowed it because there are zero active-only ones). + * + * Must be called with the drv->lock held since that protects tcs_in_use. + * + * Return: The first tcs that's free. + */ static int find_free_tcs(struct tcs_group *tcs) { int i; @@ -438,6 +568,20 @@ static int find_free_tcs(struct tcs_group *tcs) return -EBUSY; } +/** + * tcs_write() - Store messages into a TCS right now, or return -EBUSY. + * @drv: The controller. + * @msg: The data to be sent. + * + * Grabs a TCS for ACTIVE_ONLY transfers and writes the messages to it. + * + * If there are no free TCSes for ACTIVE_ONLY transfers or if a command for + * the same address is already transferring returns -EBUSY which means the + * client should retry shortly. + * + * Return: 0 on success, -EBUSY if client should retry, or an error. + * Client should have interrupts enabled for a bit before retrying. + */ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) { struct tcs_group *tcs; @@ -491,14 +635,26 @@ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) } /** - * rpmh_rsc_send_data: Validate the incoming message and write to the - * appropriate TCS block. + * rpmh_rsc_send_data() - Validate the incoming message + write to TCS block. + * @drv: The controller. + * @msg: The data to be sent. * - * @drv: the controller - * @msg: the data to be sent + * NOTES: + * - This is only used for "ACTIVE_ONLY" since the limitations of this + * function don't make sense for sleep/wake cases. + * - To do the transfer, we will grab a whole TCS for ourselves--we don't + * try to share. If there are none available we'll wait indefinitely + * for a free one. + * - This function will not wait for the commands to be finished, only for + * data to be programmed into the RPMh. See rpmh_tx_done() which will + * be called when the transfer is fully complete. + * - This function must be called with interrupts enabled. If the hardware + * is busy doing someone else's transfer we need that transfer to fully + * finish so that we can have the hardware, and to fully finish it needs + * the interrupt handler to run. If the interrupts is set to run on the + * active CPU this can never happen if interrupts are disabled. * * Return: 0 on success, -EINVAL on error. - * Note: This call blocks until a valid data is written to the TCS. */ int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) { @@ -522,13 +678,30 @@ int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) return ret; } +/** + * find_slots() - Find a place to write the given message. + * @tcs: The tcs group to search. + * @msg: The message we want to find room for. + * @tcs_id: If we return 0 from the function, we return the global ID of the + * TCS to write to here. + * @cmd_id: If we return 0 from the function, we return the index of + * the command array of the returned TCS where the client should + * start writing the message. + * + * Only for use on sleep/wake TCSes since those are the only ones we maintain + * tcs->slots for. + * + * Must be called with the tcs_lock for the group held. + * + * Return: -ENOMEM if there was no room, else 0. + */ static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg, int *tcs_id, int *cmd_id) { int slot, offset; int i = 0; - /* Do over, until we can fit the full payload in a TCS */ + /* Do over, until we can fit the full payload in a single TCS */ do { slot = bitmap_find_next_zero_area(tcs->slots, MAX_TCS_SLOTS, i, msg->num_cmds, 0); @@ -547,12 +720,14 @@ static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg, } /** - * rpmh_rsc_write_ctrl_data: Write request to the controller + * rpmh_rsc_write_ctrl_data() - Write request to controller but don't trigger. + * @drv: The controller. + * @msg: The data to be written to the controller. * - * @drv: the controller - * @msg: the data to be written to the controller + * This should only be called for for sleep/wake state, never active-only + * state. * - * There is no response returned for writing the request to the controller. + * Return: 0 if no error; else -error. */ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) { @@ -587,7 +762,6 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) /** * rpmh_rsc_ctrlr_is_busy() - Check if any of the AMCs are busy. - * * @drv: The controller * * Checks if any of the AMCs are busy in handling ACTIVE sets. @@ -624,6 +798,23 @@ static bool rpmh_rsc_ctrlr_is_busy(struct rsc_drv *drv) return false; } +/** + * rpmh_rsc_cpu_pm_callback() - Check if any of the AMCs are busy. + * @nfb: Pointer to the notifier block in struct rsc_drv. + * @action: CPU_PM_ENTER, CPU_PM_ENTER_FAILED, or CPU_PM_EXIT. + * @v: Unused + * + * This function is given to cpu_pm_register_notifier so we can be informed + * about when CPUs go down. When all CPUs go down we know no more active + * transfers will be started so we write sleep/wake sets. This function gets + * called from cpuidle code paths and also at system suspend time. + * + * If its last CPU going down and AMCs are not busy then writes cached sleep + * and wake messages to TCSes. The firmware then takes care of triggering + * them when entering deepest low power modes. + * + * Return: See cpu_pm_register_notifier. + */ static int rpmh_rsc_cpu_pm_callback(struct notifier_block *nfb, unsigned long action, void *v) { From patchwork Mon Apr 13 17:04:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486051 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4024F92C for ; Mon, 13 Apr 2020 17:04:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26A3B206E9 for ; Mon, 13 Apr 2020 17:04:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="XJLmHV8B" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732381AbgDMREv (ORCPT ); Mon, 13 Apr 2020 13:04:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732372AbgDMREu (ORCPT ); Mon, 13 Apr 2020 13:04:50 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 10C9CC00860C for ; Mon, 13 Apr 2020 10:04:50 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id e16so3779958pjp.1 for ; Mon, 13 Apr 2020 10:04:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=PZM04ZbYiFIjAv7GG0eoywCOXLJ3nJU1dPqZFxYiM54=; b=XJLmHV8BFPN0w3ZfFbumxZ5ivffYLzBB2I/hFasM9oUCz+J/Z1p1Y3lZskM7mUBlEV 7DOstP44n7DScCdKRw7ufvv87lmSyV79jUEOBRPTLxHWQ5VTsYomoRv24xbc0HRSMO3L elWJHOLz8DcVaZ5PAkF003zQ1smXOFLl6vTuA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=PZM04ZbYiFIjAv7GG0eoywCOXLJ3nJU1dPqZFxYiM54=; b=LBIEr8CjPKYDqCV6l7HhTiKizxSN4i6MqDGSFG8/uIf5UvNhj1uHJ5qtMETrwkspMV XeuGuGms6Ndx5GxPS+KvR7g23oOI5lQphrVde+MHpeJr3ZZQzhCfodbHaA7Q5fBQKDMG XjljR0LGw2fRoFatFkz8tEstsElz9r6Y6IP0pGmac5jMR3TSzVgCApznsG5UgUzKsa9f S63+lK1wBLKl4UHeJ1mR3Uhm5Gl0JAYAerft64HyileNYx5Y3OEmrKFZCSBu6QPhLwRf tlxzOcir2beckzDs7chn8hcR2bFhm2bMHN0cCq750h4sJF7eljvYqVaxIlNkOJFftN+K xdTA== X-Gm-Message-State: AGi0PubK8KzNqq7OgBt0XzzceUgZtVc/leSp/Lw32WISp0+rfg3irB6P uV0IxS4i2bDLDGlWHpBwtDgTlA== X-Google-Smtp-Source: APiQypL8k44Hgn+x9Kq4HREdWFg0ANCXjwLr3IPByI5U0qYV5QOldcYjbs2kvYAgiX1LJolO03zlwA== X-Received: by 2002:a17:90b:f16:: with SMTP id br22mr5759322pjb.89.1586797489556; Mon, 13 Apr 2020 10:04:49 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:49 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 07/10] drivers: qcom: rpmh-rsc: tcs_is_free() can just check tcs_in_use Date: Mon, 13 Apr 2020 10:04:12 -0700 Message-Id: <20200413100321.v4.7.Icf2213131ea652087f100129359052c83601f8b0@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org tcs_is_free() had two checks in it: does the software think that the TCS is free and does the hardware think that the TCS is free. I couldn't figure out in which case the hardware could think that a TCS was in-use but software thought it was free. Apparently there is no case and the extra check can be removed. This apparently has already been done in a downstream patch. Suggested-by: Maulik Shah Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - Replace ("...warn if state mismatch") w/ ("...just check tcs_in_use") Changes in v2: - Comment tcs_is_free() new for v2; replaces old patch 6. drivers/soc/qcom/rpmh-rsc.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index f0a7ada0c16f..4e76e5349c44 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -177,7 +177,6 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, * @tcs_id: The global ID of this TCS. * * Returns true if nobody has claimed this TCS (by setting tcs_in_use). - * If the TCS looks free, checks that the hardware agrees. * * Must be called with the drv->lock held or the tcs_lock for the TCS being * tested. If only the tcs_lock is held then it is possible that this @@ -188,8 +187,7 @@ static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id, */ static bool tcs_is_free(struct rsc_drv *drv, int tcs_id) { - return !test_bit(tcs_id, drv->tcs_in_use) && - read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id); + return !test_bit(tcs_id, drv->tcs_in_use); } /** From patchwork Mon Apr 13 17:04:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486061 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 69B26174A for ; Mon, 13 Apr 2020 17:05:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 471C22074B for ; Mon, 13 Apr 2020 17:05:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="U/e6j/f2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732443AbgDMRF1 (ORCPT ); Mon, 13 Apr 2020 13:05:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732377AbgDMREv (ORCPT ); Mon, 13 Apr 2020 13:04:51 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51419C0A3BE2 for ; Mon, 13 Apr 2020 10:04:51 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id t4so3585127plq.12 for ; Mon, 13 Apr 2020 10:04:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=xNVrx/cI7Cu2aF2a/gD7IMs8PmBNgX56QvuSL2GOgsU=; b=U/e6j/f2nuhIpQcM4lGNm4mG6gg2uZF/vFx/YsAipQh6wEYucIh8IJxvdNhsijNsNK HhJKGyfUZB1pZWPO9vCaxin77wWWMyy+bNJhuxIwmZhmQlCJoegvL2+SQdR03DnDvS3f A1drOrlR1tfi/taZdfgTcK7q3+JQbvSmRnfOI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=xNVrx/cI7Cu2aF2a/gD7IMs8PmBNgX56QvuSL2GOgsU=; b=XXYD+2I7EgeruJt13lF4/F29EHiHemQA1Flvksw+N8IhEChRaLwlg/SZLzeJuxTKcx UI8ncP0xWGlnyiaRQxPVJVCGeuZ6P1v38o4mDmzjUVHpSDHZorTK3A/khmbs24MW+Mf4 hViJUfVaoB9aITy0gCbheeM7iQ3isXPNelemoG6B6fEe7PBV201SFK4RTaAsbXcdM8zS j+djCPYEx/ICdukzkPtf4KsWBk+omjXaog8kVuEBiTy+vXL59giEkbvvpGkA9CPdjDLK 5wH4B3jHBs8HhrG25LuCqKMccBXJLdK3qAA0Q87oAmMmlDLf8m/gC3C7lMVkDLTREXy7 d8jg== X-Gm-Message-State: AGi0PubdD9A3YbbZon36vpVNcMN2ub3Fa1b7KjO8DOteXxQCS04mwVfM HBryL2LGhin07Nt523Div3eQeA== X-Google-Smtp-Source: APiQypIi0psKyslevtOfZ9WzW7UTKWqNYR8/2uGXcyDi3BKC73uBASSVCF3GMo2wooVKUt7nJO6Dtg== X-Received: by 2002:a17:902:8b87:: with SMTP id ay7mr18674684plb.281.1586797490877; Mon, 13 Apr 2020 10:04:50 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:50 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 08/10] drivers: qcom: rpmh-rsc: Don't double-check rpmh payload Date: Mon, 13 Apr 2020 10:04:13 -0700 Message-Id: <20200413100321.v4.8.I8e187cdfb7a31f5bb7724f1f937f2862ee464a35@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The calls rpmh_rsc_write_ctrl_data() and rpmh_rsc_send_data() are only ever called from rpmh.c. We know that rpmh.c already error checked the message. There's no reason to do it again in rpmh-rsc. Suggested-by: Maulik Shah Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: - Add "payload" to end of ("Don't double-check rpmh") patch subject Changes in v3: - ("Don't double-check rpmh") replaces ("Warning if tcs_write...") Changes in v2: None drivers/soc/qcom/rpmh-rsc.c | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 4e76e5349c44..4f2a72fdac2c 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -633,7 +633,7 @@ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) } /** - * rpmh_rsc_send_data() - Validate the incoming message + write to TCS block. + * rpmh_rsc_send_data() - Write / trigger active-only message. * @drv: The controller. * @msg: The data to be sent. * @@ -658,12 +658,6 @@ int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) { int ret; - if (!msg || !msg->cmds || !msg->num_cmds || - msg->num_cmds > MAX_RPMH_PAYLOAD) { - WARN_ON(1); - return -EINVAL; - } - do { ret = tcs_write(drv, msg); if (ret == -EBUSY) { @@ -734,16 +728,6 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg) unsigned long flags; int ret; - if (!msg || !msg->cmds || !msg->num_cmds || - msg->num_cmds > MAX_RPMH_PAYLOAD) { - pr_err("Payload error\n"); - return -EINVAL; - } - - /* Data sent to this API will not be sent immediately */ - if (msg->state == RPMH_ACTIVE_ONLY_STATE) - return -EINVAL; - tcs = get_tcs_for_msg(drv, msg); if (IS_ERR(tcs)) return PTR_ERR(tcs); From patchwork Mon Apr 13 17:04:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486057 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DCCE614B4 for ; Mon, 13 Apr 2020 17:05:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD37D206E9 for ; Mon, 13 Apr 2020 17:05:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="XNf6xwbg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732439AbgDMRFY (ORCPT ); Mon, 13 Apr 2020 13:05:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732383AbgDMREw (ORCPT ); Mon, 13 Apr 2020 13:04:52 -0400 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 71F4DC008748 for ; Mon, 13 Apr 2020 10:04:52 -0700 (PDT) Received: by mail-pl1-x642.google.com with SMTP id t4so3585149plq.12 for ; Mon, 13 Apr 2020 10:04:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=q26Dw+UqqTmrD1vcsVMRr6gyqYcT/KTjqknJbK7AfQQ=; b=XNf6xwbgBONOnkImsFWBfmWFc8KdGYTnaYt78DJD9x7/fcItmYDXVqk6GX6lTHibzF GDncNPi7K9FwrLKB8MGQJpsys+T2pOQWkfjZ7VQc/4m3TgLjGcJ+bDOvCzebwUHFTEan mi7L4ALKBh0nPBBknA2yfMAw2WzV+Ez23pugM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=q26Dw+UqqTmrD1vcsVMRr6gyqYcT/KTjqknJbK7AfQQ=; b=hq+tqlqRE5GUk+AlW4CEAi7IXWkEjGvNZiqTMQ8QblCYchM6VICBhGaUsfs6qRgywH mlT5mov3Vbse1pVY2hyn4P558BGz+Ab5M1hirlHt/TiGn+0BYIYl98sJ48asFR0gZBm+ FnPvGp9BH1c9Mu8UKo3gytnsz8EbVgUsbz/gsR7X1DluUb608QFcNCoDl1tHe3IwdBqc eWGx9joA1YxvCmOwTIMTR/z4VhkHmkJDlN34CXhz1urYBEjxUInado97iEh4m+gYPHo7 TVVEO8f8tlJt+6d190ypKMjZuWDvgftvYa4lJzzfghNWKesfUN7xy/1rr4cA1PMahx6S hWhg== X-Gm-Message-State: AGi0PubI5GNtod6ytjXYMgxK/1Zi5dvzVOEKdlwUpjGRIOMG+fn9uhFX WYy12xM/Xnbw1CClW5RTCbzSnA== X-Google-Smtp-Source: APiQypJDqUJlGkglxl+qk2Lxy1uexAWx4fRgGzrhe35cqkGX1PuIGC1QKhVodDnuDvGwdNgirB58Hw== X-Received: by 2002:a17:902:b40e:: with SMTP id x14mr18999489plr.154.1586797491939; Mon, 13 Apr 2020 10:04:51 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:51 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 09/10] drivers: qcom: rpmh-rsc: Caller handles tcs_invalidate() exclusivity Date: Mon, 13 Apr 2020 10:04:14 -0700 Message-Id: <20200413100321.v4.9.I07c1f70e0e8f2dc0004bd38970b4e258acdc773e@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Auditing tcs_invalidate() made me worried. Specifically I saw that it used spin_lock(), not spin_lock_irqsave(). That always worries me unless I can trace for sure that I'm in the interrupt handler or that someone else already disabled interrupts. Looking more at it, there is actually no reason for these locks anyway. Specifically the only reason you'd ever call rpmh_rsc_invalidate() is if you cared that the sleep/wake TCSes were empty. That means that they need to continue to be empty even after rpmh_rsc_invalidate() returns. The only way that can happen is if the caller already has done something to keep all other RPMH users out. It should be noted that even though the caller is only worried about making sleep/wake TCSes empty, they also need to worry about stopping active-only transfers if they need to handle the case where active-only transfers might borrow the wake TCS. At the moment rpmh_rsc_invalidate() is only called in PM code from the last CPU. If that later changes the caller will still need to solve the above problems themselves, so these locks will never be useful. Continuing to audit tcs_invalidate(), I found a bug. The function didn't properly check for a borrowed TCS if we hadn't recently written anything into the TCS. Specifically, if we've never written to the WAKE_TCS (or we've flushed it recently) then tcs->slots is empty. We'll early-out and we'll never call tcs_is_free(). I thought about fixing this bug by either deleting the early check for bitmap_empty() or possibly only doing it if we knew we weren't on a TCS that could be borrowed. However, I think it's better to just delete the checks. As argued above it's up to the caller to make sure that all other users of RPMH are quiet before tcs_invalidate() is called. Since callers need to handle the zero-active-TCS case anyway that means they need to make sure that the active-only transfers are quiet before calling too. The one way tcs_invalidate() gets called today is through rpmh_rsc_cpu_pm_callback() which calls rpmh_rsc_ctrlr_is_busy() to handle this. When we have another path to get to tcs_invalidate() it will also need to come up with something similar and it won't need this extra check either. If we later find some code path that actually needs this check back in (and somehow manages to be race free) we can always add it back in. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: - Removed extra "make sure" in commit message. Changes in v3: - Replaced ("irqsave()...") + ("...never -EBUSY") w/ ("Caller handles...") Changes in v2: None drivers/soc/qcom/rpmh-internal.h | 2 +- drivers/soc/qcom/rpmh-rsc.c | 38 +++++++++++--------------------- drivers/soc/qcom/rpmh.c | 5 +---- 3 files changed, 15 insertions(+), 30 deletions(-) diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index f06350cbc9a2..dba8510c0669 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -132,7 +132,7 @@ struct rsc_drv { int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg); int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg); -int rpmh_rsc_invalidate(struct rsc_drv *drv); +void rpmh_rsc_invalidate(struct rsc_drv *drv); void rpmh_tx_done(const struct tcs_request *msg, int r); int rpmh_flush(struct rpmh_ctrlr *ctrlr); diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 4f2a72fdac2c..9bd0c7c3db7c 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -198,50 +198,38 @@ static bool tcs_is_free(struct rsc_drv *drv, int tcs_id) * This will clear the "slots" variable of the given tcs_group and also * tell the hardware to forget about all entries. * - * Return: 0 if no problem, or -EAGAIN if the caller should try again in a - * bit. Caller should make sure to enable interrupts between tries. + * The caller must ensure that no other RPMH actions are happening when this + * function is called, since otherwise the device may immediately become + * used again even before this function exits. */ -static int tcs_invalidate(struct rsc_drv *drv, int type) +static void tcs_invalidate(struct rsc_drv *drv, int type) { int m; struct tcs_group *tcs = &drv->tcs[type]; - spin_lock(&tcs->lock); - if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) { - spin_unlock(&tcs->lock); - return 0; - } + /* Caller ensures nobody else is running so no lock */ + if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) + return; for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) { - if (!tcs_is_free(drv, m)) { - spin_unlock(&tcs->lock); - return -EAGAIN; - } write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0); write_tcs_reg_sync(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, m, 0); } bitmap_zero(tcs->slots, MAX_TCS_SLOTS); - spin_unlock(&tcs->lock); - - return 0; } /** * rpmh_rsc_invalidate() - Invalidate sleep and wake TCSes. * @drv: The RSC controller. * - * Return: 0 if no problem, or -EAGAIN if the caller should try again in a - * bit. Caller should make sure to enable interrupts between tries. + * The caller must ensure that no other RPMH actions are happening when this + * function is called, since otherwise the device may immediately become + * used again even before this function exits. */ -int rpmh_rsc_invalidate(struct rsc_drv *drv) +void rpmh_rsc_invalidate(struct rsc_drv *drv) { - int ret; - - ret = tcs_invalidate(drv, SLEEP_TCS); - if (!ret) - ret = tcs_invalidate(drv, WAKE_TCS); - - return ret; + tcs_invalidate(drv, SLEEP_TCS); + tcs_invalidate(drv, WAKE_TCS); } /** diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index e6a453759abd..aab6cc6bba4f 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c @@ -440,7 +440,6 @@ static int send_single(struct rpmh_ctrlr *ctrlr, enum rpmh_state state, * * Return: * * 0 - Success - * * -EAGAIN - Retry again * * Error code - Otherwise */ int rpmh_flush(struct rpmh_ctrlr *ctrlr) @@ -456,9 +455,7 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr) } /* Invalidate the TCSes first to avoid stale data */ - ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr)); - if (ret) - return ret; + rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr)); /* First flush the cached batch requests */ ret = flush_batch(ctrlr); From patchwork Mon Apr 13 17:04:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11486053 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9BBB392C for ; Mon, 13 Apr 2020 17:05:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 848FC2074B for ; Mon, 13 Apr 2020 17:05:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="E0mCZBIb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732399AbgDMRFB (ORCPT ); Mon, 13 Apr 2020 13:05:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51074 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732386AbgDMREx (ORCPT ); Mon, 13 Apr 2020 13:04:53 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91893C008769 for ; Mon, 13 Apr 2020 10:04:53 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id r14so4744539pfl.12 for ; Mon, 13 Apr 2020 10:04:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=YoTy9v1GALGtXWEjIsnk6ikaa3w8TCy0VVFYmR0SOSI=; b=E0mCZBIbcdB3lQD1HTRdYUk01U9CFJjGMxEi9JxwD8NG5whUHuwVff+wR5ygngxq0y GxKsa8ukg/tvnwovtwNu4WIoUKh3hcIaJ86nm0pSsV8imcMv9Lb/4tuSlM7pGcib3fcX SHvJU5TXRSKj5n+z00qT5YdLpTo26ZJ/UfHQ0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=YoTy9v1GALGtXWEjIsnk6ikaa3w8TCy0VVFYmR0SOSI=; b=tPAerZHIokMBALJQWM4r6RVYEXaw4HHM5lL6IB0idLab/E4I7VvmT63bPvNMXQf1k7 btjJqxYy9ZB78ghKsEAQKv8+ADcUNITAeXGcfIf29/b1/t/aZJBK9ahqhNxeK+riLUhA VgbJBmdvwl2SD2VHle5Exo47fcUd/uMZHVl82Rj25shGGiLWvG1rdg1pteM0Mw7Rr9Xu olbA3rbtrhnfZBC40VCUWcspZYUmKH0XvQQbmfmtiNDn5B8+OmHj8fAIT+aedwbGn+M7 haMQr8aH0eecOZTEP7tT8aMpwpWECSUDD2rJCUPXQc7QWWi6EsYOY/kkB+WVnVWfUeUu Tdzw== X-Gm-Message-State: AGi0PuYvSThN0SbQ6ObFJLLsMxX6qKY/OdxdHcebKVzbM7fe1vRfKprh tbZiBxBhnESu5eP/QHN2OH/Gmw== X-Google-Smtp-Source: APiQypL0Rea6oKvw07qyNd4zvgQ2zgujG6OuE32aQox0LFqc4KBOLx8rflBT87Atl3chWHnsC6djbA== X-Received: by 2002:a63:4d57:: with SMTP id n23mr18749844pgl.59.1586797493104; Mon, 13 Apr 2020 10:04:53 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id p62sm1634414pfb.93.2020.04.13.10.04.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Apr 2020 10:04:52 -0700 (PDT) From: Douglas Anderson To: Andy Gross , Bjorn Andersson , Maulik Shah Cc: swboyd@chromium.org, mka@chromium.org, Rajendra Nayak , evgreen@chromium.org, Lina Iyer , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 10/10] drivers: qcom: rpmh-rsc: read_tcs_reg()/write_tcs_reg() are not for IRQ Date: Mon, 13 Apr 2020 10:04:15 -0700 Message-Id: <20200413100321.v4.10.I2adf93809c692d0b673e1a86ea97c45644aa8d97@changeid> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog In-Reply-To: <20200413170415.32463-1-dianders@chromium.org> References: <20200413170415.32463-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The RSC_DRV_IRQ_ENABLE, RSC_DRV_IRQ_STATUS, and RSC_DRV_IRQ_CLEAR registers are not part of TCS 0. Let's not pretend that they are by using read_tcs_reg() and write_tcs_reg() and passing a bogus tcs_id of 0. We could introduce a new wrapper for these registers but it wouldn't buy us much. Let's just read/write directly. Signed-off-by: Douglas Anderson Reviewed-by: Maulik Shah Tested-by: Maulik Shah Reviewed-by: Stephen Boyd --- Changes in v4: None Changes in v3: - ("...are not for IRQ") is new for v3. Changes in v2: None drivers/soc/qcom/rpmh-rsc.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index 9bd0c7c3db7c..3c77a0eed90d 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -363,12 +363,12 @@ static void enable_tcs_irq(struct rsc_drv *drv, int tcs_id, bool enable) { u32 data; - data = read_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0); + data = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_ENABLE); if (enable) data |= BIT(tcs_id); else data &= ~BIT(tcs_id); - write_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0, data); + writel_relaxed(data, drv->tcs_base + RSC_DRV_IRQ_ENABLE); } /** @@ -389,7 +389,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p) const struct tcs_request *req; struct tcs_cmd *cmd; - irq_status = read_tcs_reg(drv, RSC_DRV_IRQ_STATUS, 0); + irq_status = readl_relaxed(drv->tcs_base + RSC_DRV_IRQ_STATUS); for_each_set_bit(i, &irq_status, BITS_PER_LONG) { req = get_req_from_tcs(drv, i); @@ -426,7 +426,7 @@ static irqreturn_t tcs_tx_done(int irq, void *p) /* Reclaim the TCS */ write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i, 0); write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, i, 0); - write_tcs_reg(drv, RSC_DRV_IRQ_CLEAR, 0, BIT(i)); + writel_relaxed(BIT(i), drv->tcs_base + RSC_DRV_IRQ_CLEAR); spin_lock(&drv->lock); clear_bit(i, drv->tcs_in_use); /* @@ -968,7 +968,8 @@ static int rpmh_rsc_probe(struct platform_device *pdev) } /* Enable the active TCS to send requests immediately */ - write_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0, drv->tcs[ACTIVE_TCS].mask); + writel_relaxed(drv->tcs[ACTIVE_TCS].mask, + drv->tcs_base + RSC_DRV_IRQ_ENABLE); spin_lock_init(&drv->client.cache_lock); INIT_LIST_HEAD(&drv->client.cache);