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 5022B3209 for ; Tue, 1 Oct 2024 10:26:34 +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=1727778394; cv=none; b=qZC5UQl1hQlGEy+PGfyKe+6Z9A5Pl+ya5Nng6CAxkp7/soVVBTNaeNdCHyUd4lkKYJQQnnzq9pW+FYj0vydOq/GcoPiTmdfPZUUCTXFuccgLTGybb6k+rbGICZsvmNsKWeb6ZBCN/2/cL8BT1CmnPvcJV1uMqlxWUC0eAqiXPB0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727778394; c=relaxed/simple; bh=X1Ftj+0coNDhLRcmsdU4GqMjxIXLZ6tFwrmu3u3S5RU=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=okCU958zou6vywIok6bwk66mveN8eiHWBTwFX9Fig7EHeXR/t5zNeexlXjejmhaFMuOGJEQn28/+uV+dS13Zary8Z115WmyHtNtWioaj9ISB9rKKwQvzDzjIzLUlPKl4N8IMZx5eTTCizEA+DgD9X2eRY+UGD4fUEy02sPqrDEo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nWu9QPgr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="nWu9QPgr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C85ACC4CEC6; Tue, 1 Oct 2024 10:26:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1727778394; bh=X1Ftj+0coNDhLRcmsdU4GqMjxIXLZ6tFwrmu3u3S5RU=; h=Subject:To:Cc:From:Date:From; b=nWu9QPgrHGgdJiGQ6HtBKm7LpPC5SgwKBbYrP0U99kGSC1cTu3JxBylH+o6vwgYku 5MZfV4tzIQ98LdH0W8ku0Gb2J3k9x40TvhSu+IdbOesj+wxtFtFBj6JqbSviJjszQn pKj+jyDcHiMLGuWBBmJpN6U8G4tyMiEPj9tiQH3A= Subject: FAILED: patch "[PATCH] serial: qcom-geni: fix false console tx restart" failed to apply to 4.19-stable tree To: johan+linaro@kernel.org,dianders@chromium.org,gregkh@linuxfoundation.org,nfraprado@collabora.com Cc: From: Date: Tue, 01 Oct 2024 12:26:19 +0200 Message-ID: <2024100118-deodorize-treble-799b@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x f97cdbbf187fefcf1fe19689cd9fdca11fe9c3eb # git commit -s git send-email --to '' --in-reply-to '2024100118-deodorize-treble-799b@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^.. Possible dependencies: f97cdbbf187f ("serial: qcom-geni: fix false console tx restart") 1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo") f8fef2fa419f ("tty: msm_serial: use dmaengine_prep_slave_sg()") 9054605ab846 ("tty: 8250_omap: use dmaengine_prep_slave_sg()") 8192fabb0db2 ("tty: 8250_dma: use dmaengine_prep_slave_sg()") 3bcb0bf65c2b ("Merge tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f97cdbbf187fefcf1fe19689cd9fdca11fe9c3eb Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 6 Sep 2024 15:13:30 +0200 Subject: [PATCH] serial: qcom-geni: fix false console tx restart MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 663abb1a7a7f ("tty: serial: qcom_geni_serial: Fix UART hang") addressed an issue with stalled tx after the console code interrupted the last bytes of a tx command by reenabling the watermark interrupt if there is data in write buffer. This can however break software flow control by re-enabling tx after the user has stopped it. Address the original issue by not clearing the CMD_DONE flag after polling for command completion. This allows the interrupt handler to start another transfer when the CMD_DONE interrupt has not been disabled due to flow control. Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP") Fixes: 663abb1a7a7f ("tty: serial: qcom_geni_serial: Fix UART hang") Cc: stable@vger.kernel.org # 4.17 Reviewed-by: Douglas Anderson Tested-by: Nícolas F. R. A. Prado Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20240906131336.23625-3-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 309c0bddf26a..b88435c0ea50 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -306,18 +306,16 @@ static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size) static void qcom_geni_serial_poll_tx_done(struct uart_port *uport) { int done; - u32 irq_clear = M_CMD_DONE_EN; done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, M_CMD_DONE_EN, true); if (!done) { writel(M_GENI_CMD_ABORT, uport->membase + SE_GENI_M_CMD_CTRL_REG); - irq_clear |= M_CMD_ABORT_EN; qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS, M_CMD_ABORT_EN, true); + writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); } - writel(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR); } static void qcom_geni_serial_abort_rx(struct uart_port *uport) @@ -378,6 +376,7 @@ 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); + 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)); @@ -422,6 +421,7 @@ __qcom_geni_serial_console_write(struct uart_port *uport, const char *s, } writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG); + writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR); qcom_geni_serial_setup_tx(uport, bytes_to_send); for (i = 0; i < count; ) { size_t chars_to_write = 0; @@ -463,7 +463,6 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, bool locked = true; unsigned long flags; u32 geni_status; - u32 irq_en; WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS); @@ -495,12 +494,6 @@ static void qcom_geni_serial_console_write(struct console *co, const char *s, * has been sent, in which case we need to look for done first. */ qcom_geni_serial_poll_tx_done(uport); - - if (!kfifo_is_empty(&uport->state->port.xmit_fifo)) { - irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN); - writel(irq_en | M_TX_FIFO_WATERMARK_EN, - uport->membase + SE_GENI_M_IRQ_EN); - } } __qcom_geni_serial_console_write(uport, s, count);