From patchwork Sat Feb 15 02:12:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Tipton X-Patchwork-Id: 11383695 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 D1D24109A for ; Sat, 15 Feb 2020 02:12:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E8882081E for ; Sat, 15 Feb 2020 02:12:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="erSLoIYA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727723AbgBOCMx (ORCPT ); Fri, 14 Feb 2020 21:12:53 -0500 Received: from mail27.static.mailgun.info ([104.130.122.27]:29188 "EHLO mail27.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727641AbgBOCMx (ORCPT ); Fri, 14 Feb 2020 21:12:53 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1581732773; h=Content-Transfer-Encoding: MIME-Version: Message-Id: Date: Subject: Cc: To: From: Sender; bh=FWN168EASJBq5LyNsiOFzXjZn7DYbmkiFzZr0eZ3VcM=; b=erSLoIYAywXvR74DKvBvQC0JXH4irHG2kBO9AMCMTRjHoHJPYwmXYSw7uuPWsstT99tb+wFn sEdemgo0REFf3zSBXi26p/okjfz84tmRxsyN6rrAOLaAEkQ9YWZnE0qJoIocTGgLqcf4Z//7 SUHy3Da4iq5Izn53hpvrJP2dHQs= X-Mailgun-Sending-Ip: 104.130.122.27 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e47539f.7f03a1d35148-smtp-out-n03; Sat, 15 Feb 2020 02:12:47 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 38597C4479C; Sat, 15 Feb 2020 02:12:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mdtipton-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mdtipton) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3D828C43383; Sat, 15 Feb 2020 02:12:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3D828C43383 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=mdtipton@codeaurora.org From: Mike Tipton To: sboyd@kernel.org, tdas@codeaurora.org Cc: bjorn.andersson@linaro.org, mturquette@baylibre.com, agross@kernel.org, linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, Mike Tipton Subject: [PATCH] clk: qcom: clk-rpmh: Wait for completion when enabling clocks Date: Fri, 14 Feb 2020 18:12:32 -0800 Message-Id: <20200215021232.1149-1-mdtipton@codeaurora.org> X-Mailer: git-send-email 2.24.0 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 current implementation always uses rpmh_write_async, which doesn't wait for completion. That's fine for disable requests since there's no immediate need for the clocks and they can be disabled in the background. However, for enable requests we need to ensure the clocks are actually enabled before returning to the client. Otherwise, clients can end up accessing their HW before the necessary clocks are enabled, which can lead to bus errors. Use the synchronous version of this API (rpmh_write) for enable requests in the active set to ensure completion. Completion isn't required for sleep/wake sets, since they don't take effect until after we enter sleep. All rpmh requests are automatically flushed prior to entering sleep. Fixes: 9c7e47025a6b ("clk: qcom: clk-rpmh: Add QCOM RPMh clock driver") Signed-off-by: Mike Tipton Reviewed-by: Bjorn Andersson --- drivers/clk/qcom/clk-rpmh.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/clk/qcom/clk-rpmh.c b/drivers/clk/qcom/clk-rpmh.c index 12bd8715dece..3137595a736b 100644 --- a/drivers/clk/qcom/clk-rpmh.c +++ b/drivers/clk/qcom/clk-rpmh.c @@ -143,6 +143,19 @@ static inline bool has_state_changed(struct clk_rpmh *c, u32 state) != (c->aggr_state & BIT(state)); } +static int clk_rpmh_send(struct clk_rpmh *c, enum rpmh_state state, + struct tcs_cmd *cmd, bool wait_for_completion) +{ + int ret; + + if (wait_for_completion) + ret = rpmh_write(c->dev, state, cmd, 1); + else + ret = rpmh_write_async(c->dev, state, cmd, 1); + + return ret; +} + static int clk_rpmh_send_aggregate_command(struct clk_rpmh *c) { struct tcs_cmd cmd = { 0 }; @@ -159,7 +172,8 @@ static int clk_rpmh_send_aggregate_command(struct clk_rpmh *c) if (cmd_state & BIT(state)) cmd.data = on_val; - ret = rpmh_write_async(c->dev, state, &cmd, 1); + ret = clk_rpmh_send(c, state, &cmd, + cmd_state && state == RPMH_ACTIVE_ONLY_STATE); if (ret) { dev_err(c->dev, "set %s state of %s failed: (%d)\n", !state ? "sleep" : @@ -267,7 +281,7 @@ static int clk_rpmh_bcm_send_cmd(struct clk_rpmh *c, bool enable) cmd.addr = c->res_addr; cmd.data = BCM_TCS_CMD(1, enable, 0, cmd_state); - ret = rpmh_write_async(c->dev, RPMH_ACTIVE_ONLY_STATE, &cmd, 1); + ret = clk_rpmh_send(c, RPMH_ACTIVE_ONLY_STATE, &cmd, enable); if (ret) { dev_err(c->dev, "set active state of %s failed: (%d)\n", c->res_name, ret);