From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Andersson Subject: Re: [PATCH v2] tty: serial: msm_serial: Fix XON/XOFF Date: Mon, 20 May 2019 11:50:08 -0700 Message-ID: <20190520185008.GX2085@tuxbook-pro> References: <20190520183848.27719-1-jorge.ramirez-ortiz@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190520183848.27719-1-jorge.ramirez-ortiz@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: Jorge Ramirez-Ortiz Cc: agross@kernel.org, david.brown@linaro.org, gregkh@linuxfoundation.org, sboyd@kernel.org, jslaby@suse.com, keescook@chromium.org, anton@enomsg.org, ccross@android.com, tony.luck@intel.com, linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-serial@vger.kernel.org On Mon 20 May 11:38 PDT 2019, Jorge Ramirez-Ortiz wrote: > When the tty layer requests the uart to throttle, the current code > executing in msm_serial will trigger "Bad mode in Error Handler" and > generate an invalid stack frame in pstore before rebooting (that is if > pstore is indeed configured: otherwise the user shall just notice a > reboot with no further information dumped to the console). > > This patch replaces the PIO byte accessor with the word accessor > already used in PIO mode. > > Fixes: 68252424a7c7 ("tty: serial: msm: Support big-endian CPUs") > Cc: stable@vger.kernel.org > Signed-off-by: Jorge Ramirez-Ortiz > Reviewed-by: Bjorn Andersson You missed Stephen's Reviewed-by: Stephen Boyd Regards, Bjorn > --- > drivers/tty/serial/msm_serial.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c > index 109096033bb1..23833ad952ba 100644 > --- a/drivers/tty/serial/msm_serial.c > +++ b/drivers/tty/serial/msm_serial.c > @@ -860,6 +860,7 @@ static void msm_handle_tx(struct uart_port *port) > struct circ_buf *xmit = &msm_port->uart.state->xmit; > struct msm_dma *dma = &msm_port->tx_dma; > unsigned int pio_count, dma_count, dma_min; > + char buf[4] = { 0 }; > void __iomem *tf; > int err = 0; > > @@ -869,10 +870,12 @@ static void msm_handle_tx(struct uart_port *port) > else > tf = port->membase + UART_TF; > > + buf[0] = port->x_char; > + > if (msm_port->is_uartdm) > msm_reset_dm_count(port, 1); > > - iowrite8_rep(tf, &port->x_char, 1); > + iowrite32_rep(tf, buf, 1); > port->icount.tx++; > port->x_char = 0; > return; > -- > 2.21.0 >