From patchwork Mon Sep 2 15:24:44 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 824847 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 41D8D19F135; Mon, 2 Sep 2024 15:25:59 +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=1725290759; cv=none; b=qE9534OsKGNaFm7EjKH3Bb8rJhgCXjhY/ZotDYUQ+9FvJm4A9F49ORe6EKlJ8oyWg7E6iNMwFuY5uGFSI3oE8Ru2zIEadfacdzu+zDi69k7ZVQm/hyn4MejIkuItyZ9qiSjAMzNUBOTIdvDGKc0tuUvhvEcY+wdVR/W8HgAKZOw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725290759; c=relaxed/simple; bh=Vn+vbILnEWPZel6iiH6ofez7iKyV+9ORZYvdR68PlGk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nF5uqO8JWLR5+4pYDLJ/j2W8/gm8yLs4VdLsQeT8qFWLs/0iXG93Kln62YINfRB6Yo4Dfy73VxzgrmD2WiScscafFq42dmNQV/hYPWQB9W6CSSKgqWeCrCL0p/nVlXgfMmOhxSrTlXSxvnv+yz+e6+Q2oTLkUdWGf6RVpI7xJlM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ds/RoX93; 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="ds/RoX93" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0F80C4CECB; Mon, 2 Sep 2024 15:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725290758; bh=Vn+vbILnEWPZel6iiH6ofez7iKyV+9ORZYvdR68PlGk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ds/RoX93hAWPSBPAHCEGQbFMq6FqumiuLioi8NaSEZ0qzH8RIKOM06/OcYnNATj74 NLYFqpXeF0q4lMWE1m3aF9bcSM5d6NITMJraBKcajTFnT972Z0a6ur07BJ0AFHX6Rx Ds4wh+tvkPTjgfBBfUV593MSwnmrFI3b9DYzV6hE9RR2cUsxIhg+UTE79aT1zp7BXU FcBk667n7fMK3OeDQRXEyWzZofYdi7sH4t4dI18pN+034HfgnjokSAtovDz+uPwLy0 dxwSq55tCJiz/gqYguyJx9wz3XZxmWbTdzYJ4KpWMMBWM2MHeEJ3sQySWAwC8X5pkA IoeMfAMsQgGjQ== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sl8wX-000000000Fd-12zI; Mon, 02 Sep 2024 17:26:13 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , =?utf-8?b?J07DrWNvbGFzIEYgLiBS?= =?utf-8?b?IC4gQSAuIFByYWRvJw==?= , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH 1/8] serial: qcom-geni: fix fifo polling timeout Date: Mon, 2 Sep 2024 17:24:44 +0200 Message-ID: <20240902152451.862-2-johan+linaro@kernel.org> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240902152451.862-1-johan+linaro@kernel.org> References: <20240902152451.862-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The qcom_geni_serial_poll_bit() can be used to wait for events like command completion and is supposed to wait for the time it takes to clear a full fifo before timing out. As noted by Doug, the current implementation does not account for start, stop and parity bits when determining the timeout. The helper also does not currently account for the shift register and the two-word intermediate transfer register. Instead of determining the fifo timeout on every call, store the timeout when updating it in set_termios() and wait for up to 19/16 the time it takes to clear the 16 word fifo to account for the shift and intermediate registers. Note that serial core has already added a 20 ms margin to the fifo timeout. Also note that the current uart_fifo_timeout() interface does unnecessary calculations on every call and also did not exists in earlier kernels so only store its result once. This also facilitates backports as earlier kernels can derive the timeout from uport->timeout, which has since been removed. Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Cc: stable@vger.kernel.org # 4.17 Reported-by: Douglas Anderson Signed-off-by: Johan Hovold --- drivers/tty/serial/qcom_geni_serial.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 69a632fefc41..e1926124339d 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -124,7 +124,7 @@ struct qcom_geni_serial_port { dma_addr_t tx_dma_addr; dma_addr_t rx_dma_addr; bool setup; - unsigned int baud; + unsigned long fifo_timeout_us; unsigned long clk_rate; void *rx_buf; u32 loopback; @@ -270,22 +270,21 @@ static bool qcom_geni_serial_poll_bit(struct uart_port *uport, { u32 reg; struct qcom_geni_serial_port *port; - unsigned int baud; - unsigned int fifo_bits; unsigned long timeout_us = 20000; struct qcom_geni_private_data *private_data = uport->private_data; if (private_data->drv) { port = to_dev_port(uport); - baud = port->baud; - if (!baud) - baud = 115200; - fifo_bits = port->tx_fifo_depth * port->tx_fifo_width; + /* - * Total polling iterations based on FIFO worth of bytes to be - * sent at current baud. Add a little fluff to the wait. + * Wait up to 19/16 the time it would take to clear a full + * FIFO, which accounts for the three words in the shift and + * intermediate registers. + * + * Note that fifo_timeout_us already has a 20 ms margin. */ - timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500; + if (port->fifo_timeout_us) + timeout_us = 19 * port->fifo_timeout_us / 16; } /* @@ -1248,7 +1247,6 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, qcom_geni_serial_stop_rx(uport); /* baud rate */ baud = uart_get_baud_rate(uport, termios, old, 300, 4000000); - port->baud = baud; sampling_rate = UART_OVERSAMPLING; /* Sampling rate is halved for IP versions >= 2.5 */ @@ -1326,8 +1324,10 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, else tx_trans_cfg |= UART_CTS_MASK; - if (baud) + if (baud) { uart_update_timeout(uport, termios->c_cflag, baud); + port->fifo_timeout_us = jiffies_to_usecs(uart_fifo_timeout(uport)); + } if (!uart_console(uport)) writel(port->loopback, From patchwork Mon Sep 2 15:24:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 824848 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 2E60C19F124; Mon, 2 Sep 2024 15:25:58 +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=1725290759; cv=none; b=KPdNii4z5mjzaFA/YL1PPyQIhnKTaD63b+9jXuTJhMHBiblNrCisaA2ViSRpwFHs7qzTMduSJMRNd8qxiJl09UYCtZVT0O0VMUN2NhNG2tyBQapxJa3XCO3j49WCc5sNfLbYUDkJaQQnY6IRYxSo2mvnV5wu2yjpZGpoq7LFRwc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725290759; c=relaxed/simple; bh=OL3j4krYLgw1/hR+PI+ZmxupOQF+uLSIhz5vZnbz3fM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DxFe0nU5FaYTzrLZlPRXz8I5UVTs+khWY60VwDApOEZU6Es6w0fxt83tjy1KNQ5Vl5Exa2DkxrGY5CoqP1a9ALP5PCO7mxX4zJdb70HTouRDrqTaHzjCmSSWcqcd+Y+4/O4B9gxv05KRmXYBdBp/5XytWcGlQKvelBP+Zfl0VRQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jL5QxJ47; 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="jL5QxJ47" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2AF1C4CEC2; Mon, 2 Sep 2024 15:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725290758; bh=OL3j4krYLgw1/hR+PI+ZmxupOQF+uLSIhz5vZnbz3fM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jL5QxJ47cRI2G7ZY+m+Yk1/arbtyZe7Bp97pWN2klYuxys+Uk2VUZ8ZZjWYs5wIY1 Cb4WBr4UqEA/K46y/uIZqTCH/kMdOW7qP6bb/hWnn/6ssU+Ponger83mZN/YDGpo76 VE8wriv/LeUNLfpoiwTMWagpbyLHPJT2Wut4kPZqPR6sA6qhz4P5juGhy/BbQUXcy0 4Ri7EGsGwPE7JrJdUbbJ+Zo4h4Zwk5zYGYaneI8Owi6bVnI2y366A4/CDwqkodNvhb vhh8UxvlXHgTELgouIaSCrPWHQ1YzdkMqLdG6/g6bNRWUvUVAYmqqOUzXWuKnpgm0x iAqryJj14+HRw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sl8wX-000000000Fj-2GhW; Mon, 02 Sep 2024 17:26:13 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , =?utf-8?b?J07DrWNvbGFzIEYgLiBS?= =?utf-8?b?IC4gQSAuIFByYWRvJw==?= , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Stephen Boyd , Konrad Dybcio , Johan Hovold Subject: [PATCH 4/8] serial: qcom-geni: fix arg types for qcom_geni_serial_poll_bit() Date: Mon, 2 Sep 2024 17:24:47 +0200 Message-ID: <20240902152451.862-5-johan+linaro@kernel.org> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240902152451.862-1-johan+linaro@kernel.org> References: <20240902152451.862-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Douglas Anderson The "offset" passed in should be unsigned since it's always a positive offset from our memory mapped IO. The "field" should be u32 since we're anding it with a 32-bit value read from the device. Suggested-by: Stephen Boyd Signed-off-by: Douglas Anderson Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20240610152420.v4.4.I24a0de52dd7336908df180fa6b698e001f3aff82@changeid Signed-off-by: Johan Hovold --- drivers/tty/serial/qcom_geni_serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 0af4a93c0af5..4625a2e5ebfb 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -266,7 +266,7 @@ static bool qcom_geni_serial_secondary_active(struct uart_port *uport) } static bool qcom_geni_serial_poll_bit(struct uart_port *uport, - int offset, int field, bool set) + unsigned int offset, u32 field, bool set) { u32 reg; struct qcom_geni_serial_port *port; From patchwork Mon Sep 2 15:24:48 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 824849 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 001E41CB501; Mon, 2 Sep 2024 15:25:58 +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=1725290759; cv=none; b=u5UtS/532kwcH3eTZPjWe6tJud/Jl88u3UwMbJj9lyzswQGsAR42AhKGJd9MhYMpSvkbPShCNTu6eU1WLG5rFDrDS9mbwoHORdX1GFMslJaC1v5Gj9TCo+s9esasEYUozdLfvY8Ic7vIuP6dHqFm00FghppQxzT1NfyOltO+454= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725290759; c=relaxed/simple; bh=6qwBsSCf/GtWxgFU1QkqVQnuxGm40YTcLu2qd495UNE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Gb9ftEh1Yz/khREI6aKS08dOaExYlagStqcW1avphxOlSje88uI22dPDkWzwPbJfOcI/uE0mc0HVtgDMSo3YkFvR+wJOMWnp/tifQ7ydv+3k0v+kjpfdUq7alBNzP5mKB3g3uohoWv75JaAKUWi5oIlx9t9TA8vGqnBf0u4pSnI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pK7K28xj; 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="pK7K28xj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB326C4CEC8; Mon, 2 Sep 2024 15:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725290758; bh=6qwBsSCf/GtWxgFU1QkqVQnuxGm40YTcLu2qd495UNE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pK7K28xjwPNKuYZW+2t5hexUwGT65M4ApJQFfDLKmjHBZI+vI7PUUzTb0A0ZaG+me 0JeeLO6r4P5aPxvZF2tNWB0ICnrKvL0FMo4k7I/pbVw7h8KLiKYM47q/LVqrgZ9Yse UjR+nrm3KKdMQPQ3Xc1iNXnepnuzi09UfLLDK5NVfdjw+H2FWOz/W3UX0raUnr+WQh FBb3G43IMbg739ObOeE4kOtOu8dYGIhgUea6c/1SB4GyjgjBLDjyaIb3XYodzPmrRJ z4gbxrqo9oQxB05E6aG9J9lFgf4VQAMcfg1pNUIcp0AiNb2P5p55AnCWbrfazyu1h0 KgI9KYpeA7soQ== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sl8wX-000000000Fm-2gkU; Mon, 02 Sep 2024 17:26:13 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , =?utf-8?b?J07DrWNvbGFzIEYgLiBS?= =?utf-8?b?IC4gQSAuIFByYWRvJw==?= , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Konrad Dybcio , Johan Hovold Subject: [PATCH 5/8] serial: qcom-geni: introduce qcom_geni_serial_poll_bitfield() Date: Mon, 2 Sep 2024 17:24:48 +0200 Message-ID: <20240902152451.862-6-johan+linaro@kernel.org> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240902152451.862-1-johan+linaro@kernel.org> References: <20240902152451.862-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Douglas Anderson With a small modification the qcom_geni_serial_poll_bit() function could be used to poll more than just a single bit. Let's generalize it. We'll make the qcom_geni_serial_poll_bit() into just a wrapper of the general function. Signed-off-by: Douglas Anderson Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20240610152420.v4.5.Ic6411eab8d9d37acc451705f583fb535cd6dadb2@changeid Signed-off-by: Johan Hovold --- drivers/tty/serial/qcom_geni_serial.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 4625a2e5ebfb..7029c39a9a21 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -265,8 +265,8 @@ static bool qcom_geni_serial_secondary_active(struct uart_port *uport) return readl(uport->membase + SE_GENI_STATUS) & S_GENI_CMD_ACTIVE; } -static bool qcom_geni_serial_poll_bit(struct uart_port *uport, - unsigned int offset, u32 field, bool set) +static bool qcom_geni_serial_poll_bitfield(struct uart_port *uport, + unsigned int offset, u32 field, u32 val) { u32 reg; struct qcom_geni_serial_port *port; @@ -294,7 +294,7 @@ static bool qcom_geni_serial_poll_bit(struct uart_port *uport, timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10; while (timeout_us) { reg = readl(uport->membase + offset); - if ((bool)(reg & field) == set) + if ((reg & field) == val) return true; udelay(10); timeout_us -= 10; @@ -302,6 +302,12 @@ static bool qcom_geni_serial_poll_bit(struct uart_port *uport, return false; } +static bool qcom_geni_serial_poll_bit(struct uart_port *uport, + unsigned int offset, u32 field, bool set) +{ + return qcom_geni_serial_poll_bitfield(uport, offset, field, set ? field : 0); +} + static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size) { u32 m_cmd; From patchwork Mon Sep 2 15:24:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 824846 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 4A4B919F13A; Mon, 2 Sep 2024 15:25:59 +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=1725290759; cv=none; b=VVqYORgwKQfnm378Ce1yzzoXXA0v1bf7hd9xNRMSlzKrOgfCfgaedyoFCq9UYJzogxMdRcY9HNMAdTvk99oVKtCtxJzj/GZWPIyHPePeg/Y+eEJxxZ0ZOxSs0RYszNff9WqmHhnoWcsBVD39wazW7b6NGVNgMKDd7Phe1HgMRuA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725290759; c=relaxed/simple; bh=IqoYBd+6Nc2oBTOWFgBukZ7TNSr6fQxp6+Ytgcq8EKc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IbwyRsDGtnFhmvl8S1R7JMbWR7UTgQc5S8+dJPH3Q3xGQ9yV1cxwAHa6nX//xhGv7yNejHfy2wzxcMoii66FQWrH7sfgbt1XksDrswy6LNENVEpPDErIfOJf0Kxx/tfxCYchxFPaw4Fy05sMoiT9eFddquwlEtIxjAz4khOvuDQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tjOesjXe; 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="tjOesjXe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4C35C4CECA; Mon, 2 Sep 2024 15:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725290758; bh=IqoYBd+6Nc2oBTOWFgBukZ7TNSr6fQxp6+Ytgcq8EKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tjOesjXeK4f0+BBlSsItSEFrUa0m+UG6KkTgHXbkjYgPnF2t2T1saG8IEZ5uratK8 FzxctbR1w4+WWW6vMJGgsBQbGRpuWsqwNoVlrF/TDUfawqynFZ6oeep47qWFGp35E0 yVU4BtcxCzgQl+8lOLeKMOt9MufA2gkT0E3JNhH02lTUSX3l1pz6WG2kCFeUQNkwTM uCrvkgdxjPeOzRhjHrmLb0FdT6KVPHW5V+9lNCuKMo6ihC6sBRwp3clqqjAH38g2iJ aZf5bpSb83l885aJ9qCRnb5OEB98MTE4hjaYT9KJl6hLCGsC+MvU2spB47MwXOV+Lr uNAdwsEUpPbxQ== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sl8wX-000000000Fp-31Rz; Mon, 02 Sep 2024 17:26:13 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , =?utf-8?b?J07DrWNvbGFzIEYgLiBS?= =?utf-8?b?IC4gQSAuIFByYWRvJw==?= , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH 6/8] serial: qcom-geni: fix console corruption Date: Mon, 2 Sep 2024 17:24:49 +0200 Message-ID: <20240902152451.862-7-johan+linaro@kernel.org> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240902152451.862-1-johan+linaro@kernel.org> References: <20240902152451.862-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The Qualcomm serial console implementation is broken and can lose characters when the serial port is also used for tty output. Specifically, the console code only waits for the current tx command to complete when all data has already been written to the fifo. When there are on-going longer transfers this often means that console output is lost when the console code inadvertently "hijacks" the current tx command instead of starting a new one. This can, for example, be observed during boot when console output that should have been interspersed with init output is truncated: [ 9.462317] qcom-snps-eusb2-hsphy fde000.phy: Registered Qcom-eUSB2 phy [ OK ] Found device KBG50ZNS256G KIOXIA Wi[ 9.471743ndows. [ 9.539915] xhci-hcd xhci-hcd.0.auto: xHCI Host Controller Add a new state variable to track how much data has been written to the fifo and use it to determine when the fifo and shift register are both empty. This is needed since there is currently no other known way to determine when the shift register is empty. This in turn allows the console code to interrupt long transfers without losing data. Note that the oops-in-progress case is similarly broken as it does not cancel any active command and also waits for the wrong status flag when attempting to drain the fifo (TX_FIFO_NOT_EMPTY_EN is only set when cancelling a command leaves data in the fifo). Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Fixes: a1fee899e5be ("tty: serial: qcom_geni_serial: Fix softlock") Fixes: 9e957a155005 ("serial: qcom-geni: Don't cancel/abort if we can't get the port lock") Cc: stable@vger.kernel.org # 4.17 Signed-off-by: Johan Hovold --- drivers/tty/serial/qcom_geni_serial.c | 48 ++++++++++++++------------- 1 file changed, 25 insertions(+), 23 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 7029c39a9a21..be620c5703f5 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -131,6 +131,7 @@ struct qcom_geni_serial_port { bool brk; unsigned int tx_remaining; + unsigned int tx_queued; int wakeup_irq; bool rx_tx_swap; bool cts_rts_swap; @@ -144,6 +145,8 @@ static const struct uart_ops qcom_geni_uart_pops; static struct uart_driver qcom_geni_console_driver; static struct uart_driver qcom_geni_uart_driver; +static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport); + static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport) { return container_of(uport, struct qcom_geni_serial_port, uport); @@ -308,6 +311,17 @@ static bool qcom_geni_serial_poll_bit(struct uart_port *uport, return qcom_geni_serial_poll_bitfield(uport, offset, field, set ? field : 0); } +static void qcom_geni_serial_drain_fifo(struct uart_port *uport) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport); + + if (!qcom_geni_serial_main_active(uport)) + return; + + qcom_geni_serial_poll_bitfield(uport, SE_GENI_M_GP_LENGTH, GP_LENGTH, + port->tx_queued); +} + static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size) { u32 m_cmd; @@ -476,7 +490,6 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, struct qcom_geni_serial_port *port; bool locked = true; unsigned long flags; - u32 geni_status; WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS); @@ -490,34 +503,20 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, else uart_port_lock_irqsave(uport, &flags); - geni_status = readl(uport->membase + SE_GENI_STATUS); + if (qcom_geni_serial_main_active(uport)) { + /* Wait for completion or drain FIFO */ + if (!locked || port->tx_remaining == 0) + qcom_geni_serial_poll_tx_done(uport); + else + qcom_geni_serial_drain_fifo(uport); - if (!locked) { - /* - * We can only get here if an oops is in progress then we were - * unable to get the lock. This means we can't safely access - * our state variables like tx_remaining. About the best we - * can do is wait for the FIFO to be empty before we start our - * transfer, so we'll do that. - */ - qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, - M_TX_FIFO_NOT_EMPTY_EN, false); - } else if ((geni_status & M_GENI_CMD_ACTIVE) && !port->tx_remaining) { - /* - * It seems we can't interrupt existing transfers if all data - * has been sent, in which case we need to look for done first. - */ - qcom_geni_serial_poll_tx_done(uport); + qcom_geni_serial_cancel_tx_cmd(uport); } __qcom_geni_serial_console_write(uport, s, count); - - if (locked) { - if (port->tx_remaining) - qcom_geni_serial_setup_tx(uport, port->tx_remaining); + if (locked) uart_port_unlock_irqrestore(uport, flags); - } } static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) @@ -698,6 +697,7 @@ static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport) writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); port->tx_remaining = 0; + port->tx_queued = 0; } static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop) @@ -924,6 +924,7 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, if (!port->tx_remaining) { qcom_geni_serial_setup_tx(uport, pending); port->tx_remaining = pending; + port->tx_queued = 0; irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN); if (!(irq_en & M_TX_FIFO_WATERMARK_EN)) @@ -932,6 +933,7 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, } qcom_geni_serial_send_chunk_fifo(uport, chunk); + port->tx_queued += chunk; /* * The tx fifo watermark is level triggered and latched. Though we had From patchwork Mon Sep 2 15:24:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 824845 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 774561A2658; Mon, 2 Sep 2024 15:25:59 +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=1725290759; cv=none; b=PQnFFPz1Ojc9j2M9IaLFKNDv6dl+AHqtZ6U3ay0dArav5ns+bJLkfokdmqqCdZlbhgOq/0g4WPuihaHTLlFv2fwSMEN256G2Krm0fP+s4g8VLcoTykh37PFxLPopHk5D31V7EVIb3IEc9PDVRX2g4PJS3xLP7+/GxUEgb0gUBWM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725290759; c=relaxed/simple; bh=V5hACLzeVR15kWP871kA/q+aCfEhF0lIeJeWRbN4eF4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pxa5SnnA9ubWELY2LoBcLz67Z7iGrHstFIVsji9avnL0svJVLqL/1hp2pvu0R8WYAcZbQ7SeiUSVP81bQXQ1OVhsWHMSo5BL/OjEzLeoNMc3cWGzVGKPimR1oVw+A3YJI9HiY5VIMwTDN/UNlkKz8qvp6w46ZEOphN4Uz2Dz8eY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WQWDqHxu; 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="WQWDqHxu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E5B43C4AF14; Mon, 2 Sep 2024 15:25:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725290759; bh=V5hACLzeVR15kWP871kA/q+aCfEhF0lIeJeWRbN4eF4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WQWDqHxugk34rZI2XEcCsQ7W4d1dHbbiY5FbmIyyIqXI7zkNVpk37Jh3dp6MNSW44 gJqNls0b/Cv8C7CUZD7uZ+tv8eUIAdBCbPICRln4T8gqJPE8eIVCUPJCaFogcC0LGg Cgk+RpbQsi1js1Ji2JKnelQzVZvuHIyzS0FXUPb1Vz9Awnzc17rtGfhePLlQqJXPOn nDYN5qlDuj1xDJkG9HZ3nFfMU5o/PpFKRuvyU4dGSUPKIhAz1XSRzgLvfMjnI57NHq JrlfjEGPrOpiu5bH7OLg0AD8c78KRKvCAIDBeHGSDSRmmvl+VGHtdz8xq6ewNCPJni ITOTwwQm+jbcw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sl8wX-000000000Fw-3rFq; Mon, 02 Sep 2024 17:26:13 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , =?utf-8?b?J07DrWNvbGFzIEYgLiBS?= =?utf-8?b?IC4gQSAuIFByYWRvJw==?= , linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH 8/8] serial: qcom-geni: fix polled console corruption Date: Mon, 2 Sep 2024 17:24:51 +0200 Message-ID: <20240902152451.862-9-johan+linaro@kernel.org> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240902152451.862-1-johan+linaro@kernel.org> References: <20240902152451.862-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The polled UART operations are used by the kernel debugger (KDB, KGDB), which can interrupt the kernel at any point in time. The current Qualcomm GENI implementation does not really work when there is on-going serial output as it inadvertently "hijacks" the current tx command, which can result in both the initial debugger output being corrupted as well as the corruption of any on-going serial output (up to 4k characters) when execution resumes: 0190: abcdefghijklmnopqrstuvwxyz0123456789 0190: abcdefghijklmnopqrstuvwxyz0123456789 0191: abcdefghijklmnop[ 50.825552] sysrq: DEBUG qrstuvwxyz0123456789 0191: abcdefghijklmnopqrstuvwxyz0123456789 Entering kdb (current=0xffff53510b4cd280, pid 640) on processor 2 due to Keyboard Entry [2]kdb> go omlji3h3h2g2g1f1f0e0ezdzdycycxbxbwawav :t72r2rp o9n976k5j5j4i4i3h3h2g2g1f1f0e0ezdzdycycxbxbwawavu:t7t8s8s8r2r2q0q0p o9n9n8ml6k6k5j5j4i4i3h3h2g2g1f1f0e0ezdzdycycxbxbwawav v u:u:t9t0s4s4rq0p o9n9n8m8m7l7l6k6k5j5j40q0p p o o9n9n8m8m7l7l6k6k5j5j4i4i3h3h2g2g1f1f0e0ezdzdycycxbxbwawav :t8t9s4s4r4r4q0q0p Fix this by making sure that the polled output implementation waits for the tx fifo to drain before cancelling any on-going longer transfers. As the polled code cannot take any locks, leave the state variables as they are and instead make sure that the interrupt handler always starts a new tx command when there is data in the write buffer. Since the debugger can interrupt the interrupt handler when it is writing data to the tx fifo, it is currently not possible to fully prevent losing up to 64 bytes of tty output on resume. Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Cc: stable@vger.kernel.org # 4.17 Signed-off-by: Johan Hovold Reviewed-by: Douglas Anderson --- drivers/tty/serial/qcom_geni_serial.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index fbed143c90a3..cf8bafd99a09 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -145,6 +145,7 @@ static const struct uart_ops qcom_geni_uart_pops; static struct uart_driver qcom_geni_console_driver; static struct uart_driver qcom_geni_uart_driver; +static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport); static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport); static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport) @@ -403,13 +404,14 @@ static int qcom_geni_serial_get_char(struct uart_port *uport) static void qcom_geni_serial_poll_put_char(struct uart_port *uport, unsigned char c) { - writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG); + if (qcom_geni_serial_main_active(uport)) { + qcom_geni_serial_poll_tx_done(uport); + __qcom_geni_serial_cancel_tx_cmd(uport); + } + writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); qcom_geni_serial_setup_tx(uport, 1); - WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, - M_TX_FIFO_WATERMARK_EN, true)); writel(c, uport->membase + SE_GENI_TX_FIFOn); - writel(M_TX_FIFO_WATERMARK_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); qcom_geni_serial_poll_tx_done(uport); } #endif @@ -688,13 +690,10 @@ static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport) writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN); } -static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport) +static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport) { struct qcom_geni_serial_port *port = to_dev_port(uport); - if (!qcom_geni_serial_main_active(uport)) - return; - geni_se_cancel_m_cmd(&port->se); if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, M_CMD_CANCEL_EN, true)) { @@ -704,6 +703,16 @@ static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport) writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); } writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); +} + +static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport) +{ + struct qcom_geni_serial_port *port = to_dev_port(uport); + + if (!qcom_geni_serial_main_active(uport)) + return; + + __qcom_geni_serial_cancel_tx_cmd(uport); port->tx_remaining = 0; port->tx_queued = 0; @@ -930,7 +939,7 @@ static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport, if (!chunk) goto out_write_wakeup; - if (!port->tx_remaining) { + if (!active) { qcom_geni_serial_setup_tx(uport, pending); port->tx_remaining = pending; port->tx_queued = 0;