From patchwork Thu Sep 21 08:54:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huangzheng Lai X-Patchwork-Id: 725045 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B09EE7D0A9 for ; Thu, 21 Sep 2023 20:03:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231497AbjIUUDe (ORCPT ); Thu, 21 Sep 2023 16:03:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231593AbjIUUC7 (ORCPT ); Thu, 21 Sep 2023 16:02:59 -0400 Received: from SHSQR01.spreadtrum.com (unknown [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5528D573F4; Thu, 21 Sep 2023 10:18:43 -0700 (PDT) Received: from SHSQR01.spreadtrum.com (localhost [127.0.0.2] (may be forged)) by SHSQR01.spreadtrum.com with ESMTP id 38L8vNUw048315; Thu, 21 Sep 2023 16:57:23 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from dlp.unisoc.com ([10.29.3.86]) by SHSQR01.spreadtrum.com with ESMTP id 38L8tWjg040670; Thu, 21 Sep 2023 16:55:32 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from SHDLP.spreadtrum.com (shmbx04.spreadtrum.com [10.0.1.214]) by dlp.unisoc.com (SkyGuard) with ESMTPS id 4Rrq0C6JnCz2SZykd; Thu, 21 Sep 2023 16:52:11 +0800 (CST) Received: from xm9614pcu.spreadtrum.com (10.13.2.29) by shmbx04.spreadtrum.com (10.0.1.214) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 21 Sep 2023 16:55:30 +0800 From: Huangzheng Lai To: Andi Shyti CC: Orson Zhai , Baolin Wang , Chunyan Zhang , , , huangzheng lai , Huangzheng Lai , Xiongpeng Wu Subject: [PATCH V2 4/7] i2c: sprd: Add I2C controller driver to support dynamic switching of 400K/1M/3.4M frequency Date: Thu, 21 Sep 2023 16:54:54 +0800 Message-ID: <20230921085457.32446-5-Huangzheng.Lai@unisoc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> References: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> MIME-Version: 1.0 X-Originating-IP: [10.13.2.29] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To shmbx04.spreadtrum.com (10.0.1.214) X-MAIL: SHSQR01.spreadtrum.com 38L8tWjg040670 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org When I2C-slaves supporting different frequencies use the same I2C controller, the I2C controller usually only operates at lower frequencies. In order to improve the performance of I2C-slaves transmission supporting faster frequencies, we dynamically configure the I2C operating frequency based on the value of the input parameter msg ->flag. Signed-off-by: Huangzheng Lai --- drivers/i2c/busses/i2c-sprd.c | 101 +++++++++++++++++++--------------- 1 file changed, 57 insertions(+), 44 deletions(-) diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c index dec627ef408c..f1f7fad42ecd 100644 --- a/drivers/i2c/busses/i2c-sprd.c +++ b/drivers/i2c/busses/i2c-sprd.c @@ -75,7 +75,14 @@ #define SPRD_I2C_PM_TIMEOUT 1000 /* timeout (ms) for transfer message */ #define I2C_XFER_TIMEOUT 1000 - +/* dynamic modify clk_freq flag */ +#define I2C_3M4_FLAG 0x0100 +#define I2C_1M_FLAG 0x0080 +#define I2C_400K_FLAG 0x0040 + +#define I2C_FREQ_400K 400000 +#define I2C_FREQ_1M 1000000 +#define I2C_FREQ_3_4M 3400000 /* SPRD i2c data structure */ struct sprd_i2c { struct i2c_adapter adap; @@ -94,6 +101,49 @@ struct sprd_i2c { int err; }; +static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq) +{ + u32 apb_clk = i2c_dev->src_clk; + /* + * From I2C databook, the prescale calculation formula: + * prescale = freq_i2c / (4 * freq_scl) - 1; + */ + u32 i2c_dvd = apb_clk / (4 * freq) - 1; + /* + * From I2C databook, the high period of SCL clock is recommended as + * 40% (2/5), and the low period of SCL clock is recommended as 60% + * (3/5), then the formula should be: + * high = (prescale * 2 * 2) / 5 + * low = (prescale * 2 * 3) / 5 + */ + u32 high = ((i2c_dvd << 1) * 2) / 5; + u32 low = ((i2c_dvd << 1) * 3) / 5; + u32 div0 = I2C_ADDR_DVD0_CALC(high, low); + u32 div1 = I2C_ADDR_DVD1_CALC(high, low); + + writel(div0, i2c_dev->base + ADDR_DVD0); + writel(div1, i2c_dev->base + ADDR_DVD1); + + /* Start hold timing = hold time(us) * source clock */ + switch (freq) { + case I2C_MAX_STANDARD_MODE_FREQ: + writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD); + break; + case I2C_MAX_FAST_MODE_FREQ: + writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); + break; + case I2C_MAX_FAST_MODE_PLUS_FREQ: + writel((8 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + writel((8 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); + break; + default: + dev_err(i2c_dev->dev, "Unsupported frequency: %d\n", freq); + break; + } +} + static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count) { writel(count, i2c_dev->base + I2C_COUNT); @@ -269,6 +319,12 @@ static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap, sprd_i2c_send_stop(i2c_dev, !!is_last_msg); } + if (msg->flags & I2C_400K_FLAG) + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_400K); + else if (msg->flags & I2C_1M_FLAG) + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_1M); + else if (msg->flags & I2C_3M4_FLAG) + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_3_4M); /* * We should enable rx fifo full interrupt to get data when receiving * full data. @@ -331,49 +387,6 @@ static const struct i2c_algorithm sprd_i2c_algo = { .functionality = sprd_i2c_func, }; -static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq) -{ - u32 apb_clk = i2c_dev->src_clk; - /* - * From I2C databook, the prescale calculation formula: - * prescale = freq_i2c / (4 * freq_scl) - 1; - */ - u32 i2c_dvd = apb_clk / (4 * freq) - 1; - /* - * From I2C databook, the high period of SCL clock is recommended as - * 40% (2/5), and the low period of SCL clock is recommended as 60% - * (3/5), then the formula should be: - * high = (prescale * 2 * 2) / 5 - * low = (prescale * 2 * 3) / 5 - */ - u32 high = ((i2c_dvd << 1) * 2) / 5; - u32 low = ((i2c_dvd << 1) * 3) / 5; - u32 div0 = I2C_ADDR_DVD0_CALC(high, low); - u32 div1 = I2C_ADDR_DVD1_CALC(high, low); - - writel(div0, i2c_dev->base + ADDR_DVD0); - writel(div1, i2c_dev->base + ADDR_DVD1); - - /* Start hold timing = hold time(us) * source clock */ - switch (freq) { - case I2C_MAX_STANDARD_MODE_FREQ: - writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD); - break; - case I2C_MAX_FAST_MODE_FREQ: - writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); - break; - case I2C_MAX_FAST_MODE_PLUS_FREQ: - writel((8 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); - break; - case I2C_MAX_HIGH_SPEED_MODE_FREQ: - writel((8 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); - break; - default: - dev_err(i2c_dev->dev, "Unsupported frequency: %d\n", freq); - break; - } -} - static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) { u32 tmp = I2C_DVD_OPT; From patchwork Thu Sep 21 08:54:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huangzheng Lai X-Patchwork-Id: 725044 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F94AE7D0A2 for ; Thu, 21 Sep 2023 20:15:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231405AbjIUUPn (ORCPT ); Thu, 21 Sep 2023 16:15:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231448AbjIUUPa (ORCPT ); Thu, 21 Sep 2023 16:15:30 -0400 Received: from SHSQR01.spreadtrum.com (unknown [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B6F4573E4; Thu, 21 Sep 2023 10:18:39 -0700 (PDT) Received: from SHSQR01.spreadtrum.com (localhost [127.0.0.2] (may be forged)) by SHSQR01.spreadtrum.com with ESMTP id 38L8vJhq047982; Thu, 21 Sep 2023 16:57:19 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from dlp.unisoc.com ([10.29.3.86]) by SHSQR01.spreadtrum.com with ESMTP id 38L8tWHj040736; Thu, 21 Sep 2023 16:55:32 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from SHDLP.spreadtrum.com (shmbx04.spreadtrum.com [10.0.1.214]) by dlp.unisoc.com (SkyGuard) with ESMTPS id 4Rrq0D4mh7z2SZtbS; Thu, 21 Sep 2023 16:52:12 +0800 (CST) Received: from xm9614pcu.spreadtrum.com (10.13.2.29) by shmbx04.spreadtrum.com (10.0.1.214) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 21 Sep 2023 16:55:31 +0800 From: Huangzheng Lai To: Andi Shyti CC: Orson Zhai , Baolin Wang , Chunyan Zhang , , , huangzheng lai , Huangzheng Lai , Xiongpeng Wu Subject: [PATCH V2 5/7] i2c: sprd: Configure the enable bit of the I2C controller before each transmission initiation Date: Thu, 21 Sep 2023 16:54:55 +0800 Message-ID: <20230921085457.32446-6-Huangzheng.Lai@unisoc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> References: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> MIME-Version: 1.0 X-Originating-IP: [10.13.2.29] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To shmbx04.spreadtrum.com (10.0.1.214) X-MAIL: SHSQR01.spreadtrum.com 38L8tWHj040736 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org When a timeout exception occurs in the I2C driver, the I2C controller will be reset, and after resetting, control bits such as I2C_EN and I2C_INT_EN will be reset to 0, and the I2C master cannot initiate Transmission unless sprd_i2c_enable() is executed. To address this issue, this patch places sprd_i2c_enable() before each transmission initiation to ensure that the necessary control bits of the I2C controller are configured. Signed-off-by: Huangzheng Lai --- drivers/i2c/busses/i2c-sprd.c | 38 +++++++++++++++++------------------ 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c index f1f7fad42ecd..b65729ba7d5a 100644 --- a/drivers/i2c/busses/i2c-sprd.c +++ b/drivers/i2c/busses/i2c-sprd.c @@ -352,6 +352,23 @@ static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap, return i2c_dev->err; } +static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) +{ + u32 tmp = I2C_DVD_OPT; + + writel(tmp, i2c_dev->base + I2C_CTL); + + sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD); + sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD); + + sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq); + sprd_i2c_reset_fifo(i2c_dev); + sprd_i2c_clear_irq(i2c_dev); + + tmp = readl(i2c_dev->base + I2C_CTL); + writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); +} + static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) { @@ -362,6 +379,8 @@ static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap, if (ret < 0) return ret; + sprd_i2c_enable(i2c_dev); + for (im = 0; im < num - 1; im++) { ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0); if (ret) @@ -387,23 +406,6 @@ static const struct i2c_algorithm sprd_i2c_algo = { .functionality = sprd_i2c_func, }; -static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) -{ - u32 tmp = I2C_DVD_OPT; - - writel(tmp, i2c_dev->base + I2C_CTL); - - sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD); - sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD); - - sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq); - sprd_i2c_reset_fifo(i2c_dev); - sprd_i2c_clear_irq(i2c_dev); - - tmp = readl(i2c_dev->base + I2C_CTL); - writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); -} - static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id) { struct sprd_i2c *i2c_dev = dev_id; @@ -669,8 +671,6 @@ static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev) if (ret) return ret; - sprd_i2c_enable(i2c_dev); - return 0; } From patchwork Thu Sep 21 08:54:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huangzheng Lai X-Patchwork-Id: 725046 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43D37E7D0A6 for ; Thu, 21 Sep 2023 19:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231124AbjIUTbP (ORCPT ); Thu, 21 Sep 2023 15:31:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230273AbjIUTaR (ORCPT ); Thu, 21 Sep 2023 15:30:17 -0400 Received: from SHSQR01.spreadtrum.com (mx1.unisoc.com [222.66.158.135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DACE257B02; Thu, 21 Sep 2023 10:18:47 -0700 (PDT) Received: from SHSQR01.spreadtrum.com (localhost [127.0.0.2] (may be forged)) by SHSQR01.spreadtrum.com with ESMTP id 38L8vR5h048606; Thu, 21 Sep 2023 16:57:27 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from dlp.unisoc.com ([10.29.3.86]) by SHSQR01.spreadtrum.com with ESMTP id 38L8tXmD040792; Thu, 21 Sep 2023 16:55:33 +0800 (+08) (envelope-from Huangzheng.Lai@unisoc.com) Received: from SHDLP.spreadtrum.com (shmbx04.spreadtrum.com [10.0.1.214]) by dlp.unisoc.com (SkyGuard) with ESMTPS id 4Rrq0F2frGz2SZykd; Thu, 21 Sep 2023 16:52:13 +0800 (CST) Received: from xm9614pcu.spreadtrum.com (10.13.2.29) by shmbx04.spreadtrum.com (10.0.1.214) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 21 Sep 2023 16:55:32 +0800 From: Huangzheng Lai To: Andi Shyti CC: Orson Zhai , Baolin Wang , Chunyan Zhang , , , huangzheng lai , Huangzheng Lai , Xiongpeng Wu Subject: [PATCH V2 6/7] i2c: sprd: Increase the waiting time for I2C transmission to avoid system crash issues Date: Thu, 21 Sep 2023 16:54:56 +0800 Message-ID: <20230921085457.32446-7-Huangzheng.Lai@unisoc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> References: <20230921085457.32446-1-Huangzheng.Lai@unisoc.com> MIME-Version: 1.0 X-Originating-IP: [10.13.2.29] X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To shmbx04.spreadtrum.com (10.0.1.214) X-MAIL: SHSQR01.spreadtrum.com 38L8tXmD040792 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Due to the relatively low priority of the isr_thread, when the CPU load is high, the execution of sprd_i2c_isr_thread will be delayed. After the waiting time is exceeded, the I2C driver will perform operations such as disabling the I2C controller. Later, when sprd_i2c_isr_thread is called by the CPU, there will be kernel panic caused by illegal access to the IIC register. After pressure testing, we found that increasing the IIC waiting time to 10 seconds can avoid this problem. Fixes: 0b884fe71f9e ("i2c: sprd: use a specific timeout to avoid system hang up issue") Cc: # v5.11+ Signed-off-by: Huangzheng Lai --- drivers/i2c/busses/i2c-sprd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c index b65729ba7d5a..dbdac89ad482 100644 --- a/drivers/i2c/busses/i2c-sprd.c +++ b/drivers/i2c/busses/i2c-sprd.c @@ -74,7 +74,7 @@ /* timeout (ms) for pm runtime autosuspend */ #define SPRD_I2C_PM_TIMEOUT 1000 /* timeout (ms) for transfer message */ -#define I2C_XFER_TIMEOUT 1000 +#define I2C_XFER_TIMEOUT 10000 /* dynamic modify clk_freq flag */ #define I2C_3M4_FLAG 0x0100 #define I2C_1M_FLAG 0x0080