On Tue, Sep 6, 2022 at 5:15 AM Johannes Schneider <johannes.schnei...@leica-geosystems.com> wrote: > > only waiting for TXEMPTY leads to corrupted messages going over the > wire - which is fixed by making use of the FIFO > > this change is following the linux kernel uart driver > (drivers/tty/serial/imx.c), which also checks UTS_TXFULL > instead of UTS_TXEMPTY > > Signed-off-by: Johannes Schneider <johannes.schnei...@leica-geosystems.com> > Reviewed-by: Peng Fan <peng....@nxp.com> > Reviewed-by: Fabio Estevam <feste...@denx.de> > --- > > (no changes since v1) > > drivers/serial/serial_mxc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/serial/serial_mxc.c b/drivers/serial/serial_mxc.c > index ee17a960d4..af1fd1ea9b 100644 > --- a/drivers/serial/serial_mxc.c > +++ b/drivers/serial/serial_mxc.c > @@ -311,7 +311,7 @@ static int mxc_serial_putc(struct udevice *dev, const > char ch) > struct mxc_serial_plat *plat = dev_get_plat(dev); > struct mxc_uart *const uart = plat->reg; > > - if (!(readl(&uart->ts) & UTS_TXEMPTY)) > + if (readl(&uart->ts) & UTS_TXFULL) > return -EAGAIN; > > writel(ch, &uart->txd); > -- > 2.25.1 >
Johannes, Since this patch I find an issue with an IMX6 board of mine gwventana: Prior to this patch the board boots with: DRAM: 1 GiB GSCv2 : v52 0x9981 RST:VIN WDT:disabled board_temp:43C RTC : 1970-01-01 0:56:15 UTC Core: 67 devices, 22 uclasses, devicetree: separate WDT: Started watchdog@20bc000 with servicing every 1000ms (60s timeout) NAND: 2048 MiB ... and following this patch I get: ... DRAM: 1 GiB GSCv2 : v52 0x9981 RST:VIN WDT:disabled board_temp:29C RTC : 1970-01-01 ~�KW�'$H�$V�W��Y.KH�� uclasses, devicetree: separate WDT: Started watchdog@20bc000 with servicing every 1000ms (60s timeout) NAND: 2048 MiB ... The RTC line is displayed from drivers/misc/gsc.c and the Core: comes from dm_announce. Somehow in between the FIFO does not get drained before dm_announce gets called. Adding a delay after the RTC print or reverting this patch. Any ideas? Best Regards, Tim