| Message ID | 1462427683-3646-2-git-send-email-vinod.koul@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 05 May 2016 07:54:43 +0200, Vinod Koul wrote: > > From: Jeeja KP <jeeja.kp@intel.com> > > If the DMAs are not being quiesced properly, it may lead to > stability issues, so the recommendation is to wait till DMAs are > stopped. > > After setting the stop bit of RIRB/CORB DMA, we should wait for > stop bit to be set. > > Signed-off-by: Jeeja KP <jeeja.kp@intel.com> > Signed-off-by: Vinod Koul <vinod.koul@intel.com> > --- > changes in v2: > - use common wait routine as suggested by Takashi > > sound/hda/hdac_controller.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c > index 8c486235c905..9fee464e5d49 100644 > --- a/sound/hda/hdac_controller.c > +++ b/sound/hda/hdac_controller.c > @@ -80,6 +80,22 @@ void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus) > } > EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io); > > +/* wait for cmd dmas till they are stopped */ > +static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus) > +{ > + unsigned long timeout; > + > + timeout = jiffies + msecs_to_jiffies(100); > + while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN) > + && time_before(jiffies, timeout)) > + udelay(10); > + > + timeout = jiffies + msecs_to_jiffies(100); > + while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN) > + && time_before(jiffies, timeout)) > + udelay(10); This will end up with doubled timeout. But it doesn't matter so much in practice. So I applied the patch as is. thanks, Takashi > +} > + > /** > * snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers > * @bus: HD-audio core bus > @@ -90,6 +106,7 @@ void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus) > /* disable ringbuffer DMAs */ > snd_hdac_chip_writeb(bus, RIRBCTL, 0); > snd_hdac_chip_writeb(bus, CORBCTL, 0); > + hdac_wait_for_cmd_dmas(bus); > /* disable unsolicited responses */ > snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0); > spin_unlock_irq(&bus->reg_lock); > -- > 1.9.1 >
On Sun, May 08, 2016 at 11:45:50AM +0200, Takashi Iwai wrote: > > +/* wait for cmd dmas till they are stopped */ > > +static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus) > > +{ > > + unsigned long timeout; > > + > > + timeout = jiffies + msecs_to_jiffies(100); > > + while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN) > > + && time_before(jiffies, timeout)) > > + udelay(10); > > + > > + timeout = jiffies + msecs_to_jiffies(100); > > + while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN) > > + && time_before(jiffies, timeout)) > > + udelay(10); > > This will end up with doubled timeout. But it doesn't matter so much > in practice. So I applied the patch as is. Thanks Takashi
diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c index 8c486235c905..9fee464e5d49 100644 --- a/sound/hda/hdac_controller.c +++ b/sound/hda/hdac_controller.c @@ -80,6 +80,22 @@ void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus) } EXPORT_SYMBOL_GPL(snd_hdac_bus_init_cmd_io); +/* wait for cmd dmas till they are stopped */ +static void hdac_wait_for_cmd_dmas(struct hdac_bus *bus) +{ + unsigned long timeout; + + timeout = jiffies + msecs_to_jiffies(100); + while ((snd_hdac_chip_readb(bus, RIRBCTL) & AZX_RBCTL_DMA_EN) + && time_before(jiffies, timeout)) + udelay(10); + + timeout = jiffies + msecs_to_jiffies(100); + while ((snd_hdac_chip_readb(bus, CORBCTL) & AZX_CORBCTL_RUN) + && time_before(jiffies, timeout)) + udelay(10); +} + /** * snd_hdac_bus_stop_cmd_io - clean up CORB/RIRB buffers * @bus: HD-audio core bus @@ -90,6 +106,7 @@ void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus) /* disable ringbuffer DMAs */ snd_hdac_chip_writeb(bus, RIRBCTL, 0); snd_hdac_chip_writeb(bus, CORBCTL, 0); + hdac_wait_for_cmd_dmas(bus); /* disable unsolicited responses */ snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, 0); spin_unlock_irq(&bus->reg_lock);