| Message ID | E1eWn56-0005rw-N5@debutante (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
On 03.01.2018 18:44, Mark Brown wrote: > The patch > > spi: sh-msiof: Fix timeout failures for TX-only DMA transfers > > has been applied to the spi tree at > > https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git Would it make sense to forward this to -stable, too? Best regards Dirk > All being well this means that it will be integrated into the linux-next > tree (usually sometime in the next 24 hours) and sent to Linus during > the next merge window (or sooner if it is a bug fix), however if > problems are discovered then the patch may be dropped or reverted. > > You may get further e-mails resulting from automated or manual testing > and review of the tree, please engage with people reporting problems and > send followup patches addressing any issues that are reported if needed. > > If any updates are required or you are submitting further changes they > should be sent as incremental updates against current git, existing > patches will not be replaced. > > Please add any relevant lists and maintainers to the CCs when replying > to this mail. > > Thanks, > Mark > >>From 89434c3c35081439627baa2225622d5bd12242fe Mon Sep 17 00:00:00 2001 > From: Geert Uytterhoeven <geert+renesas@glider.be> > Date: Wed, 3 Jan 2018 18:11:14 +0100 > Subject: [PATCH] spi: sh-msiof: Fix timeout failures for TX-only DMA transfers > > When using RX (with or without TX), the DMA interrupt triggers > completion when the RX FIFO has been emptied, i.e. after the full > transfer has finished. > > However, when using TX without RX, the DMA interrupt triggers completion > as soon as the DMA engine has filled the TX FIFO, i.e. before the full > transfer has finished. Then sh_msiof_modify_ctr_wait() will spin until > the transfer has really finished and the TFSE bit is cleared, for at > most 1 ms. For slow speeds and/or large transfers, this may cause > timeouts and transfer failures: > > spi_sh_msiof e6e10000.spi: failed to shut down hardware > 74x164 spi2.0: SPI transfer failed: -110 > spi_master spi2: failed to transfer one message from queue > 74x164 spi2.0: Failed writing: -110 > > Fix this by waiting explicitly until the TX FIFO has been emptied. > > Based on a patch in the BSP by Hiromitsu Yamasaki. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > Signed-off-by: Mark Brown <broonie@kernel.org> > --- > drivers/spi/spi-sh-msiof.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c > index fcd261f98b9f..06bc4b170c47 100644 > --- a/drivers/spi/spi-sh-msiof.c > +++ b/drivers/spi/spi-sh-msiof.c > @@ -784,11 +784,21 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx, > goto stop_dma; > } > > - /* wait for tx fifo to be emptied / rx fifo to be filled */ > + /* wait for tx/rx DMA completion */ > ret = sh_msiof_wait_for_completion(p); > if (ret) > goto stop_reset; > > + if (!rx) { > + reinit_completion(&p->done); > + sh_msiof_write(p, IER, IER_TEOFE); > + > + /* wait for tx fifo to be emptied */ > + ret = sh_msiof_wait_for_completion(p); > + if (ret) > + goto stop_reset; > + } > + > /* clear status bits */ > sh_msiof_reset_str(p); >
Hi Dirk, On Thu, Jan 4, 2018 at 8:05 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote: > On 03.01.2018 18:44, Mark Brown wrote: >> The patch >> >> spi: sh-msiof: Fix timeout failures for TX-only DMA transfers >> >> has been applied to the spi tree at >> >> https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git > > Would it make sense to forward this to -stable, too? Yes, _after_ it has landed in Linus' tree. I didn't add a Fixes tag, as the fix needs changes to apply to any pre-4.13 kernel. Most probably it will be picked up by stable automatically, as it has the magic word "Fix" in the one-line summary. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
On Thu, Jan 04, 2018 at 09:26:31AM +0100, Geert Uytterhoeven wrote: > On Thu, Jan 4, 2018 at 8:05 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote: > > On 03.01.2018 18:44, Mark Brown wrote: > > Would it make sense to forward this to -stable, too? > Yes, _after_ it has landed in Linus' tree. > I didn't add a Fixes tag, as the fix needs changes to apply to any pre-4.13 > kernel. > Most probably it will be picked up by stable automatically, as it has the > magic word "Fix" in the one-line summary. I'm also always a bit worried about just sending things on when nobody's been complaining about problems without lots of testing.
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c index fcd261f98b9f..06bc4b170c47 100644 --- a/drivers/spi/spi-sh-msiof.c +++ b/drivers/spi/spi-sh-msiof.c @@ -784,11 +784,21 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx, goto stop_dma; } - /* wait for tx fifo to be emptied / rx fifo to be filled */ + /* wait for tx/rx DMA completion */ ret = sh_msiof_wait_for_completion(p); if (ret) goto stop_reset; + if (!rx) { + reinit_completion(&p->done); + sh_msiof_write(p, IER, IER_TEOFE); + + /* wait for tx fifo to be emptied */ + ret = sh_msiof_wait_for_completion(p); + if (ret) + goto stop_reset; + } + /* clear status bits */ sh_msiof_reset_str(p);