From patchwork Tue Aug 22 15:25:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kaiser X-Patchwork-Id: 13361088 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 59772EE49A3 for ; Tue, 22 Aug 2023 15:29:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=f/6mV5QeHS/B0HqV0Y1aUwBjMyQqINghGaR69nAoG88=; b=fB1hYm107xf2kQ mgS76ipZlTgTkKlbij96aERS7ItZ7yXdg0Pp5+BXxOH9KfEE7qQMkgVjDLcP7i91MpD/ohTttgMYH R0kOX1oTDwsgmwW3L1RGgeYVdCE7vVk2J+rUiG4n4mWUrNGG72Ji+U/vFunh6RUbCrxdYXgnd4e0w qFXD6Pn60GMdwUyz7Huo3Qlasb/q3bXb341eNnGNcxKPzxjS/4hu0mK58+Uv9WjJGpYwApWrlyKzc rEBuqTyUXQunTw1ZNAsnfN5X61Ml3rHbb3TZGlqOmoBE6G6QGDiFFhO3NydZnWMXXERYCWzJ4tDIE 07Li9tZIaKyi2DmHDgeg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJC-00GMrL-1g; Tue, 22 Aug 2023 15:28:42 +0000 Received: from viti.kaiser.cx ([2a01:238:43fe:e600:cd0c:bd4a:7a3:8e9f]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJ9-00GMoL-0T for linux-arm-kernel@lists.infradead.org; Tue, 22 Aug 2023 15:28:40 +0000 Received: from pd956d63d.dip0.t-ipconnect.de ([217.86.214.61] helo=martin-debian-2.paytec.ch) by viti.kaiser.cx with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1qYTJ3-0006li-UF; Tue, 22 Aug 2023 17:28:34 +0200 From: Martin Kaiser To: Herbert Xu Cc: linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Martin Kaiser Subject: [PATCH 1/3] hwrng: imx-rngc - use polling to detect end of self test Date: Tue, 22 Aug 2023 17:25:51 +0200 Message-Id: <20230822152553.190858-2-martin@kaiser.cx> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230822152553.190858-1-martin@kaiser.cx> References: <20230822152553.190858-1-martin@kaiser.cx> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230822_082839_327789_54D468C4 X-CRM114-Status: GOOD ( 13.29 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Use polling to detect the end of the rngc self test. This is much simpler than using an interrupt and a completion. Active waiting is no disadvantage here. The self test is run during probe, there's nothing we could do in parallel at this time. Signed-off-by: Martin Kaiser --- drivers/char/hw_random/imx-rngc.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c index e4b385b01b11..85207535fd12 100644 --- a/drivers/char/hw_random/imx-rngc.c +++ b/drivers/char/hw_random/imx-rngc.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #define RNGC_VER_ID 0x0000 @@ -101,21 +102,19 @@ static inline void imx_rngc_irq_unmask(struct imx_rngc *rngc) static int imx_rngc_self_test(struct imx_rngc *rngc) { - u32 cmd; + u32 cmd, status; int ret; - imx_rngc_irq_unmask(rngc); - /* run self test */ cmd = readl(rngc->base + RNGC_COMMAND); writel(cmd | RNGC_CMD_SELF_TEST, rngc->base + RNGC_COMMAND); - ret = wait_for_completion_timeout(&rngc->rng_op_done, msecs_to_jiffies(RNGC_TIMEOUT)); - imx_rngc_irq_mask_clear(rngc); - if (!ret) - return -ETIMEDOUT; + ret = readl_poll_timeout(rngc->base + RNGC_STATUS, status, + status & RNGC_STATUS_ST_DONE, 1000, RNGC_TIMEOUT * 1000); + if (ret < 0) + return ret; - return rngc->err_reg ? -EIO : 0; + return readl(rngc->base + RNGC_ERROR) ? -EIO : 0; } static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait) From patchwork Tue Aug 22 15:25:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kaiser X-Patchwork-Id: 13361090 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B493BEE4993 for ; Tue, 22 Aug 2023 15:29:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=m7PwYZ2O2qyi0ugTAnAmj1jE4UMtU6l6R4MfI5AaPK4=; b=3ydLM67f3ejRd6 E1Uwod4C+4UnQGWy4DyXGWPYy7zMYOytCss1kQgbxh9I0KO32MhltOnZa/Yx4QaBUgs2WGIggHVeS Uknr80h+55myvkjkdN8pHaRPgd814yQZGuVb0rvgcSPr+KVTEHwjVCqZKor6JjGGKU91h7JfdtJVw 4orbgPdhh20cDcmjXkHfZgx8GjEEfTBgt/zykspYb3DjVmpT8jgiRNNEY9aApk0sm9l7jRbhpmmzC lfadcrcirjhkPrY4fLS1B5cyfumImpntVuI12yWhzIZUdM7aheZVLPoi4khDFGxL8P9OhWKFKedlA e3FU7MyQ0vuiJiq97xBA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJQ-00GMuz-1M; Tue, 22 Aug 2023 15:28:56 +0000 Received: from viti.kaiser.cx ([2a01:238:43fe:e600:cd0c:bd4a:7a3:8e9f]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJ9-00GMoM-0W for linux-arm-kernel@lists.infradead.org; Tue, 22 Aug 2023 15:28:41 +0000 Received: from pd956d63d.dip0.t-ipconnect.de ([217.86.214.61] helo=martin-debian-2.paytec.ch) by viti.kaiser.cx with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1qYTJ4-0006li-T3; Tue, 22 Aug 2023 17:28:34 +0200 From: Martin Kaiser To: Herbert Xu Cc: linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Martin Kaiser Subject: [PATCH 2/3] hwrng: imx-rngc - read status register for error checks Date: Tue, 22 Aug 2023 17:25:52 +0200 Message-Id: <20230822152553.190858-3-martin@kaiser.cx> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230822152553.190858-1-martin@kaiser.cx> References: <20230822152553.190858-1-martin@kaiser.cx> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230822_082839_344784_819260DF X-CRM114-Status: GOOD ( 13.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The error bit in the status register of the imx-rngc is set for any kind of error. Details about the error can be read from the bits in the error status register. In the imx_rngc_self_test, we just need the info if there was an error or not. We can check the status register, there's no need to read the error status register. Signed-off-by: Martin Kaiser --- drivers/char/hw_random/imx-rngc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c index 85207535fd12..d2df468fd460 100644 --- a/drivers/char/hw_random/imx-rngc.c +++ b/drivers/char/hw_random/imx-rngc.c @@ -114,7 +114,7 @@ static int imx_rngc_self_test(struct imx_rngc *rngc) if (ret < 0) return ret; - return readl(rngc->base + RNGC_ERROR) ? -EIO : 0; + return (status & RNGC_STATUS_ERROR) ? -EIO : 0; } static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait) From patchwork Tue Aug 22 15:25:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Kaiser X-Patchwork-Id: 13361091 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BD463EE49A3 for ; Tue, 22 Aug 2023 15:29:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BTgO7CD4jyX7/ZGAkzTmU71QczmbtBEkD6yOVlhFcHQ=; b=bW4qYZ5YhtC7Hh /gBbwpbu+RUZKW8dfn2BYDS6tw6ym8rgUF8hYDH+ZBlOM3/28Qi0MNgIQG7/QwHOdlEP0+rKt/Dmu mu0dc6TvvkFXuveEBdfOZuujiclMeRCnWfvIasbECkU7KegFhKWgDJh5b9o89lh+uEVete5+YiP7P P4nH3pdmEdY7yMuHAaRbNypixCvzxtWZcwhHRnugCDvIRMisFMJikfdOvU5UrKaFhvL6AmHDnzGTa TpbDSkER1IhD6vFEeB1Tx9rS6Ri2sYUzGALJB1/nYu9JwyheHnbBUOusp0rPYlxPkzxBKPQDbYHxI IhoyJJIvYm3lDVn40mPQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJQ-00GMvJ-2w; Tue, 22 Aug 2023 15:28:56 +0000 Received: from viti.kaiser.cx ([2a01:238:43fe:e600:cd0c:bd4a:7a3:8e9f]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qYTJA-00GMok-1A for linux-arm-kernel@lists.infradead.org; Tue, 22 Aug 2023 15:28:42 +0000 Received: from pd956d63d.dip0.t-ipconnect.de ([217.86.214.61] helo=martin-debian-2.paytec.ch) by viti.kaiser.cx with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1qYTJ6-0006li-5r; Tue, 22 Aug 2023 17:28:36 +0200 From: Martin Kaiser To: Herbert Xu Cc: linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Martin Kaiser Subject: [PATCH 3/3] hwrng: imx-rngc - use polling to wait for end of seeding Date: Tue, 22 Aug 2023 17:25:53 +0200 Message-Id: <20230822152553.190858-4-martin@kaiser.cx> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230822152553.190858-1-martin@kaiser.cx> References: <20230822152553.190858-1-martin@kaiser.cx> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230822_082840_560691_16E91316 X-CRM114-Status: GOOD ( 22.08 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Use polling to wait until the imx-rngc is properly seeded. We do this only in the init function when the imx-rngc becomes active. Polling is ok at this time, there's nothing else we could do while we're waiting. We can now remove the code for the interrupt and the completion. Signed-off-by: Martin Kaiser --- drivers/char/hw_random/imx-rngc.c | 81 ++++--------------------------- 1 file changed, 9 insertions(+), 72 deletions(-) diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c index d2df468fd460..7ab9aada72d0 100644 --- a/drivers/char/hw_random/imx-rngc.c +++ b/drivers/char/hw_random/imx-rngc.c @@ -63,12 +63,6 @@ struct imx_rngc { struct clk *clk; void __iomem *base; struct hwrng rng; - struct completion rng_op_done; - /* - * err_reg is written only by the irq handler and read only - * when interrupts are masked, we need no spinlock - */ - u32 err_reg; }; @@ -91,15 +85,6 @@ static inline void imx_rngc_irq_mask_clear(struct imx_rngc *rngc) writel(cmd, rngc->base + RNGC_COMMAND); } -static inline void imx_rngc_irq_unmask(struct imx_rngc *rngc) -{ - u32 ctrl; - - ctrl = readl(rngc->base + RNGC_CONTROL); - ctrl &= ~(RNGC_CTRL_MASK_DONE | RNGC_CTRL_MASK_ERROR); - writel(ctrl, rngc->base + RNGC_CONTROL); -} - static int imx_rngc_self_test(struct imx_rngc *rngc) { u32 cmd, status; @@ -143,56 +128,32 @@ static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait) return retval ? retval : -EIO; } -static irqreturn_t imx_rngc_irq(int irq, void *priv) -{ - struct imx_rngc *rngc = (struct imx_rngc *)priv; - u32 status; - - /* - * clearing the interrupt will also clear the error register - * read error and status before clearing - */ - status = readl(rngc->base + RNGC_STATUS); - rngc->err_reg = readl(rngc->base + RNGC_ERROR); - - imx_rngc_irq_mask_clear(rngc); - - if (status & (RNGC_STATUS_SEED_DONE | RNGC_STATUS_ST_DONE)) - complete(&rngc->rng_op_done); - - return IRQ_HANDLED; -} - static int imx_rngc_init(struct hwrng *rng) { struct imx_rngc *rngc = container_of(rng, struct imx_rngc, rng); - u32 cmd, ctrl; + u32 cmd, ctrl, status, err_reg; int ret; /* clear error */ cmd = readl(rngc->base + RNGC_COMMAND); writel(cmd | RNGC_CMD_CLR_ERR, rngc->base + RNGC_COMMAND); - imx_rngc_irq_unmask(rngc); - /* create seed, repeat while there is some statistical error */ do { /* seed creation */ cmd = readl(rngc->base + RNGC_COMMAND); writel(cmd | RNGC_CMD_SEED, rngc->base + RNGC_COMMAND); - ret = wait_for_completion_timeout(&rngc->rng_op_done, msecs_to_jiffies(RNGC_TIMEOUT)); - if (!ret) { - ret = -ETIMEDOUT; - goto err; - } + ret = readl_poll_timeout(rngc->base + RNGC_STATUS, status, + status & RNGC_STATUS_SEED_DONE, 1000, RNGC_TIMEOUT * 1000); + if (ret < 0) + return ret; - } while (rngc->err_reg == RNGC_ERROR_STATUS_STAT_ERR); + err_reg = readl(rngc->base + RNGC_ERROR); + } while (err_reg == RNGC_ERROR_STATUS_STAT_ERR); - if (rngc->err_reg) { - ret = -EIO; - goto err; - } + if (err_reg) + return -EIO; /* * enable automatic seeding, the rngc creates a new seed automatically @@ -202,23 +163,7 @@ static int imx_rngc_init(struct hwrng *rng) ctrl |= RNGC_CTRL_AUTO_SEED; writel(ctrl, rngc->base + RNGC_CONTROL); - /* - * if initialisation was successful, we keep the interrupt - * unmasked until imx_rngc_cleanup is called - * we mask the interrupt ourselves if we return an error - */ return 0; - -err: - imx_rngc_irq_mask_clear(rngc); - return ret; -} - -static void imx_rngc_cleanup(struct hwrng *rng) -{ - struct imx_rngc *rngc = container_of(rng, struct imx_rngc, rng); - - imx_rngc_irq_mask_clear(rngc); } static int __init imx_rngc_probe(struct platform_device *pdev) @@ -254,12 +199,9 @@ static int __init imx_rngc_probe(struct platform_device *pdev) if (rng_type != RNGC_TYPE_RNGC && rng_type != RNGC_TYPE_RNGB) return -ENODEV; - init_completion(&rngc->rng_op_done); - rngc->rng.name = pdev->name; rngc->rng.init = imx_rngc_init; rngc->rng.read = imx_rngc_read; - rngc->rng.cleanup = imx_rngc_cleanup; rngc->rng.quality = 19; rngc->dev = &pdev->dev; @@ -267,11 +209,6 @@ static int __init imx_rngc_probe(struct platform_device *pdev) imx_rngc_irq_mask_clear(rngc); - ret = devm_request_irq(&pdev->dev, - irq, imx_rngc_irq, 0, pdev->name, (void *)rngc); - if (ret) - return dev_err_probe(&pdev->dev, ret, "Can't get interrupt working.\n"); - if (self_test) { ret = imx_rngc_self_test(rngc); if (ret)