From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD0292D94AE for ; Wed, 30 Jul 2025 14:00:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753884010; cv=none; b=T7FslDbDs74aB0Ll56sKWhfRz2VOCI11ULYkxoqC9zFFGo0+CaRPU9O5remrciJqsWCu2eVWudKnI3M7w+aduEYgP3phWarCadiAYNSp6rQG+W7sdIZu0FbyS1zXm3VMyaN49Z44r99mfSCy8xReX26XP/XjR2DzJskQs6l2dXQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753884010; c=relaxed/simple; bh=cz1Ln2tQC9Y6+8c9Cw+AZJCjMZGLxClEo1/+BmQKV8M=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kpAXz8iItTBwJ+5HQYdJ6NqoxXVRLob/rGGLrM7VJeTISQw0abJQdsV+qA9sNfQRFOIgkFCT7KFE15TZ/J0NeHNStypw5ELDIdfzQT5LOWLHooQHyKf7ed4BjmdfBdHw1bdb33bPzxxwo8mcmzZcj+0K42oPNG7tWIbMGubOPek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LqxpiRj4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LqxpiRj4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51332C4CEE3; Wed, 30 Jul 2025 14:00:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753884010; bh=cz1Ln2tQC9Y6+8c9Cw+AZJCjMZGLxClEo1/+BmQKV8M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LqxpiRj4nFh2pPgiEMMhO+greScTF1GBA6EdQkY3pbvjX994LcC1KeY+y2KAZLBG2 VS9JYzJzaLQXVjgcYHKAnnLyHhDNZuy3i9WasPtp/7mnM7SSCNGjOTSm0YlTi6rNIk /TY4I82SDZtCmqHu8BYGSEztsMEdqmf1UkFUBkpbj2ZA4QPIMiUliTDZ7r4JeMO13y 3nZjYlhA2ngwNcoWu+AZpgQfWSmpL9OamQYn2q8dz3UDsYIkFNtOB0MUtJzWNKD4JS g9o9es5dhaCUQMxWmNhaS0kPsMzHbwfzAB5Ll0pjKvGGqh8jWIJFZfAAz4UjlrZFl9 152dsTvAhnbBA== From: Sasha Levin To: stable@vger.kernel.org Cc: Alain Volmat , Andi Shyti , Wolfram Sang , Sasha Levin Subject: [PATCH 6.6.y v2 3/5] i2c: stm32f7: perform most of irq job in threaded handler Date: Wed, 30 Jul 2025 10:00:00 -0400 Message-Id: <20250730140002.3814528-3-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250730140002.3814528-1-sashal@kernel.org> References: <2025072104-bacteria-resend-dcff@gregkh> <20250730140002.3814528-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Alain Volmat [ Upstream commit e6103cd45ef0e14eb02f0666bc6b494902cfe821 ] The irq handling is currently split between the irq handler and the threaded irq handler. Some of the handling (such as dma related stuffs) done within the irq handler might sleep or take some time leading to issues if the kernel is built with realtime constraints. In order to fix that, perform an overall rework to perform most of the job within the threaded handler and only keep fifo access in the non threaded handler. Signed-off-by: Alain Volmat Reviewed-by: Andi Shyti Signed-off-by: Wolfram Sang Stable-dep-of: 6aae87fe7f18 ("i2c: stm32f7: unmap DMA mapped buffer") Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-stm32f7.c | 126 ++++++++++++++----------------- 1 file changed, 56 insertions(+), 70 deletions(-) diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index cb9093b43be2..74fef11fd18a 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -1496,17 +1496,11 @@ static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev) static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) { struct stm32f7_i2c_dev *i2c_dev = data; - struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; - struct stm32_i2c_dma *dma = i2c_dev->dma; - void __iomem *base = i2c_dev->base; - u32 status, mask; - int ret = IRQ_HANDLED; + u32 status; - /* Check if the interrupt if for a slave device */ - if (!i2c_dev->master_mode) { - ret = stm32f7_i2c_slave_isr_event(i2c_dev); - return ret; - } + /* Check if the interrupt is for a slave device */ + if (!i2c_dev->master_mode) + return IRQ_WAKE_THREAD; status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); @@ -1518,6 +1512,29 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) if (status & STM32F7_I2C_ISR_RXNE) stm32f7_i2c_read_rx_data(i2c_dev); + /* Wake up the thread if other flags are raised */ + if (status & + (STM32F7_I2C_ISR_NACKF | STM32F7_I2C_ISR_STOPF | + STM32F7_I2C_ISR_TC | STM32F7_I2C_ISR_TCR)) + return IRQ_WAKE_THREAD; + + return IRQ_HANDLED; +} + +static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data) +{ + struct stm32f7_i2c_dev *i2c_dev = data; + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + void __iomem *base = i2c_dev->base; + u32 status, mask; + int ret; + + if (!i2c_dev->master_mode) + return stm32f7_i2c_slave_isr_event(i2c_dev); + + status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + /* NACK received */ if (status & STM32F7_I2C_ISR_NACKF) { dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n", @@ -1530,33 +1547,28 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) f7_msg->result = -ENXIO; } - /* STOP detection flag */ - if (status & STM32F7_I2C_ISR_STOPF) { - /* Disable interrupts */ - if (stm32f7_i2c_is_slave_registered(i2c_dev)) - mask = STM32F7_I2C_XFER_IRQ_MASK; + if (status & STM32F7_I2C_ISR_TCR) { + if (f7_msg->smbus) + stm32f7_i2c_smbus_reload(i2c_dev); else - mask = STM32F7_I2C_ALL_IRQ_MASK; - stm32f7_i2c_disable_irq(i2c_dev, mask); - - /* Clear STOP flag */ - writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); - - if (i2c_dev->use_dma && !f7_msg->result) { - ret = IRQ_WAKE_THREAD; - } else { - i2c_dev->master_mode = false; - complete(&i2c_dev->complete); - } + stm32f7_i2c_reload(i2c_dev); } /* Transfer complete */ if (status & STM32F7_I2C_ISR_TC) { + /* Wait for dma transfer completion before sending next message */ + if (i2c_dev->use_dma && !f7_msg->result) { + ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ); + if (!ret) { + dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__); + stm32f7_i2c_disable_dma_req(i2c_dev); + dmaengine_terminate_async(dma->chan_using); + f7_msg->result = -ETIMEDOUT; + } + } if (f7_msg->stop) { mask = STM32F7_I2C_CR2_STOP; stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); - } else if (i2c_dev->use_dma && !f7_msg->result) { - ret = IRQ_WAKE_THREAD; } else if (f7_msg->smbus) { stm32f7_i2c_smbus_rep_start(i2c_dev); } else { @@ -1566,47 +1578,18 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) } } - if (status & STM32F7_I2C_ISR_TCR) { - if (f7_msg->smbus) - stm32f7_i2c_smbus_reload(i2c_dev); + /* STOP detection flag */ + if (status & STM32F7_I2C_ISR_STOPF) { + /* Disable interrupts */ + if (stm32f7_i2c_is_slave_registered(i2c_dev)) + mask = STM32F7_I2C_XFER_IRQ_MASK; else - stm32f7_i2c_reload(i2c_dev); - } - - return ret; -} - -static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data) -{ - struct stm32f7_i2c_dev *i2c_dev = data; - struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; - struct stm32_i2c_dma *dma = i2c_dev->dma; - u32 status; - int ret; - - /* - * Wait for dma transfer completion before sending next message or - * notity the end of xfer to the client - */ - ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ); - if (!ret) { - dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__); - stm32f7_i2c_disable_dma_req(i2c_dev); - dmaengine_terminate_async(dma->chan_using); - f7_msg->result = -ETIMEDOUT; - } + mask = STM32F7_I2C_ALL_IRQ_MASK; + stm32f7_i2c_disable_irq(i2c_dev, mask); - status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + /* Clear STOP flag */ + writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); - if (status & STM32F7_I2C_ISR_TC) { - if (f7_msg->smbus) { - stm32f7_i2c_smbus_rep_start(i2c_dev); - } else { - i2c_dev->msg_id++; - i2c_dev->msg++; - stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg); - } - } else { i2c_dev->master_mode = false; complete(&i2c_dev->complete); } @@ -1614,7 +1597,7 @@ static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data) return IRQ_HANDLED; } -static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data) +static irqreturn_t stm32f7_i2c_isr_error_thread(int irq, void *data) { struct stm32f7_i2c_dev *i2c_dev = data; struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; @@ -2201,8 +2184,11 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) if (ret) return dev_err_probe(&pdev->dev, ret, "Failed to request irq event\n"); - ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0, - pdev->name, i2c_dev); + ret = devm_request_threaded_irq(&pdev->dev, irq_error, + NULL, + stm32f7_i2c_isr_error_thread, + IRQF_ONESHOT, + pdev->name, i2c_dev); if (ret) return dev_err_probe(&pdev->dev, ret, "Failed to request irq error\n"); -- 2.39.5