From patchwork Tue Oct 1 12:50:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 832372 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 3C2F61A0AFB; Tue, 1 Oct 2024 12:51:11 +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=1727787071; cv=none; b=MJam2Oz39iIoqPKB0N2+wltP1rvGOZnbcEARskuvNqW98Z06B5jJGC0OSlpTYkp4RNvqudhCTqTeI1dGDsQ2tu38UQ/0HwWJ774wki++8pBupiESQxsxjX5ebt916lTHcXh4aNEegQgTmH4dZzWMCKQfuj/Wj2ReKyX9hmgFmOE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727787071; c=relaxed/simple; bh=1YDwGAT9d5r98sjNJsTBq19sCn2srPOrFhzzQ2PFT4g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mwtFN58nKDwIBe+vamZZZh8vbWnI/YBfiTrMzLhnnmZmt6GPCWyCb2Ks8FhhL4xq586pYrcKGl6U6dacBv6A8f1hI9KJLLoqjApNekvGWrJyUNr7ZBLeY8PSEYGdOBGC1tZ12FKpcncDothuhl0mA4/h5vCXtCSmMzOjYM13f6M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YOmPsqE4; 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="YOmPsqE4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6DC3C4CED2; Tue, 1 Oct 2024 12:51:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727787071; bh=1YDwGAT9d5r98sjNJsTBq19sCn2srPOrFhzzQ2PFT4g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YOmPsqE4C9yMR0T+4SsdeQy8l8gyG69CDCXCf9GPGrhCEL24IU58+GD/WGfOHkRgZ mXnVzNpvCdiZ0vupH/ykosXZvXU5OSDiSaXWOzK2ggnIq0er7jG1w/i965NCPgW/Wx UfDKvfo9YVA+/xDMawhReIXJNo8p6rKwqFGkmMEf2jKDB+wiaTJqNsccIYpLTf10BZ vF+QWFipc1ZA7slXIwyKZR1GAXmsJ8wpCBPjuxjQl3gxGYMKyvEgIZEHbOQ7//a63p 7FbSIe34mRysEH5JEKIi4X9iiTHn6XyQDj/ij8bG7yK1NejlcNUFrzKXQRztqepfEH 7emdrcOEkLOog== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1svcLP-000000002mI-0SiE; Tue, 01 Oct 2024 14:51:11 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , Bjorn Andersson , Konrad Dybcio , Douglas Anderson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Johan Hovold , stable@vger.kernel.org, Bartosz Golaszewski Subject: [PATCH v2 3/7] serial: qcom-geni: fix dma rx cancellation Date: Tue, 1 Oct 2024 14:50:29 +0200 Message-ID: <20241001125033.10625-4-johan+linaro@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241001125033.10625-1-johan+linaro@kernel.org> References: <20241001125033.10625-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Make sure to wait for the DMA transfer to complete when cancelling the rx command on stop_rx(). This specifically prevents the DMA completion interrupt from firing after rx has been restarted, something which can lead to an IOMMU fault and hosed rx when the interrupt handler unmaps the DMA buffer for the new command: qcom_geni_serial 988000.serial: serial engine reports 0 RX bytes in! arm-smmu 15000000.iommu: FSR = 00000402 [Format=2 TF], SID=0x563 arm-smmu 15000000.iommu: FSYNR0 = 00210013 [S1CBNDX=33 WNR PLVL=3] Bluetooth: hci0: command 0xfc00 tx timeout Bluetooth: hci0: Reading QCA version information failed (-110) Also add the missing state machine reset which is needed in case cancellation fails. Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA") Cc: stable@vger.kernel.org # 6.3 Cc: Bartosz Golaszewski Signed-off-by: Johan Hovold --- drivers/tty/serial/qcom_geni_serial.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index b6a8729cee6d..dea688db0d7c 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -787,17 +787,27 @@ static void qcom_geni_serial_start_rx_fifo(struct uart_port *uport) static void qcom_geni_serial_stop_rx_dma(struct uart_port *uport) { struct qcom_geni_serial_port *port = to_dev_port(uport); + bool done; if (!qcom_geni_serial_secondary_active(uport)) return; geni_se_cancel_s_cmd(&port->se); - qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS, - S_CMD_CANCEL_EN, true); - - if (qcom_geni_serial_secondary_active(uport)) + done = qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT, + RX_EOT, true); + if (done) { + writel(RX_EOT | RX_DMA_DONE, + uport->membase + SE_DMA_RX_IRQ_CLR); + } else { qcom_geni_serial_abort_rx(uport); + writel(1, uport->membase + SE_DMA_RX_FSM_RST); + qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT, + RX_RESET_DONE, true); + writel(RX_RESET_DONE | RX_DMA_DONE, + uport->membase + SE_DMA_RX_IRQ_CLR); + } + if (port->rx_dma_addr) { geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr, DMA_RX_BUF_SIZE);