[Intel-gfx] [PATCH v2] drm/i915: remove check for aux irq
Ville Syrjälä
ville.syrjala at linux.intel.com
Thu Jun 21 16:01:12 UTC 2018
On Tue, Jun 19, 2018 at 08:24:33AM -0700, Lucas De Marchi wrote:
> On Tue, Jun 19, 2018 at 7:06 AM Ville Syrjälä
> <ville.syrjala at linux.intel.com> wrote:
> >
> > On Fri, Jun 15, 2018 at 02:51:06PM -0700, Lucas De Marchi wrote:
> > > On Fri, Jun 15, 2018 at 08:58:28PM +0300, Ville Syrjälä wrote:
> > > > On Wed, May 23, 2018 at 11:04:35AM -0700, Lucas De Marchi wrote:
> > > > > This became dead code with commit 309bd8ed464f ("drm/i915: Reinstate
> > > > > GMBUS and AUX interrupts on gen4/g4x").
> > > > >
> > > > > v2: Move comment about HW behavior to where decision is made to enable
> > > > > MSI (Ville).
> > > > >
> > > > > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > > > Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
> > > > > ---
> > > > > drivers/gpu/drm/i915/i915_drv.c | 6 ++++++
> > > > > drivers/gpu/drm/i915/i915_drv.h | 10 ----------
> > > > > drivers/gpu/drm/i915/intel_dp.c | 22 +++++++---------------
> > > > > drivers/gpu/drm/i915/intel_drv.h | 1 -
> > > > > drivers/gpu/drm/i915/intel_psr.c | 2 +-
> > > > > 5 files changed, 14 insertions(+), 27 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> > > > > index 9c449b8d8eab..a1461de20472 100644
> > > > > --- a/drivers/gpu/drm/i915/i915_drv.c
> > > > > +++ b/drivers/gpu/drm/i915/i915_drv.c
> > > > > @@ -1189,6 +1189,12 @@ static int i915_driver_init_hw(struct drm_i915_private *dev_priv)
> > > > > * get lost on g4x as well, and interrupt delivery seems to stay
> > > > > * properly dead afterwards. So we'll just disable them for all
> > > > > * pre-gen5 chipsets.
> > > > > + *
> > > > > + * dp aux and gmbus irq on gen4 seems to be able to generate legacy
> > > > > + * interrupts even when in MSI mode. This results in spurious
> > > > > + * interrupt warnings if the legacy irq no. is shared with another
> > > > > + * device. The kernel then disables that interrupt source and so
> > > > > + * prevents the other device from working properly.
> > > > > */
> > > > > if (INTEL_GEN(dev_priv) >= 5) {
> > > > > if (pci_enable_msi(pdev) < 0)
> > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > > > > index b86ed6401120..c5e1f648c47c 100644
> > > > > --- a/drivers/gpu/drm/i915/i915_drv.h
> > > > > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > > > > @@ -2558,16 +2558,6 @@ intel_info(const struct drm_i915_private *dev_priv)
> > > > > (IS_CANNONLAKE(dev_priv) || \
> > > > > IS_SKL_GT3(dev_priv) || IS_SKL_GT4(dev_priv))
> > > > >
> > > > > -/*
> > > > > - * dp aux and gmbus irq on gen4 seems to be able to generate legacy interrupts
> > > > > - * even when in MSI mode. This results in spurious interrupt warnings if the
> > > > > - * legacy irq no. is shared with another device. The kernel then disables that
> > > > > - * interrupt source and so prevents the other device from working properly.
> > > > > - *
> > > > > - * Since we don't enable MSI anymore on gen4, we can always use GMBUS/AUX
> > > > > - * interrupts.
> > > > > - */
> > > > > -#define HAS_AUX_IRQ(dev_priv) true
> > > > > #define HAS_GMBUS_IRQ(dev_priv) (INTEL_GEN(dev_priv) >= 4)
> > > > >
> > > > > /* With the 945 and later, Y tiling got adjusted so that it was 32 128-byte
> > > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > > > > index ce07bd794aed..1dab40056df7 100644
> > > > > --- a/drivers/gpu/drm/i915/intel_dp.c
> > > > > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > > > > @@ -936,7 +936,7 @@ intel_dp_check_edp(struct intel_dp *intel_dp)
> > > > > }
> > > > >
> > > > > static uint32_t
> > > > > -intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
> > > > > +intel_dp_aux_wait_done(struct intel_dp *intel_dp)
> > > > > {
> > > > > struct drm_i915_private *dev_priv = to_i915(intel_dp_to_dev(intel_dp));
> > > > > i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
> > > > > @@ -944,14 +944,10 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
> > > > > bool done;
> > > > >
> > > > > #define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
> > > > > - if (has_aux_irq)
> > > > > - done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
> > > > > - msecs_to_jiffies_timeout(10));
> > > > > - else
> > > > > - done = wait_for(C, 10) == 0;
> > > > > + done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
> > > > > + msecs_to_jiffies_timeout(10));
> > > > > if (!done)
> > > > > - DRM_ERROR("dp aux hw did not signal timeout (has irq: %i)!\n",
> > > > > - has_aux_irq);
> > > > > + DRM_ERROR("dp aux hw did not signal timeout!\n");
> > > > > #undef C
> > > > >
> > > > > return status;
> > > > > @@ -1016,7 +1012,6 @@ static uint32_t skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
> > > > > }
> > > > >
> > > > > static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
> > > > > - bool has_aux_irq,
> > > > > int send_bytes,
> > > > > uint32_t aux_clock_divider)
> > > > > {
> > > > > @@ -1037,7 +1032,7 @@ static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
> > > > >
> > > > > return DP_AUX_CH_CTL_SEND_BUSY |
> > > > > DP_AUX_CH_CTL_DONE |
> > > > > - (has_aux_irq ? DP_AUX_CH_CTL_INTERRUPT : 0) |
> > > > > + DP_AUX_CH_CTL_INTERRUPT |
> > > > > DP_AUX_CH_CTL_TIME_OUT_ERROR |
> > > > > timeout |
> > > > > DP_AUX_CH_CTL_RECEIVE_ERROR |
> > > > > @@ -1047,13 +1042,12 @@ static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
> > > > > }
> > > > >
> > > > > static uint32_t skl_get_aux_send_ctl(struct intel_dp *intel_dp,
> > > > > - bool has_aux_irq,
> > > > > int send_bytes,
> > > > > uint32_t unused)
> > > > > {
> > > > > return DP_AUX_CH_CTL_SEND_BUSY |
> > > > > DP_AUX_CH_CTL_DONE |
> > > > > - (has_aux_irq ? DP_AUX_CH_CTL_INTERRUPT : 0) |
> > > > > + DP_AUX_CH_CTL_INTERRUPT |
> > > > > DP_AUX_CH_CTL_TIME_OUT_ERROR |
> > > > > DP_AUX_CH_CTL_TIME_OUT_MAX |
> > > > > DP_AUX_CH_CTL_RECEIVE_ERROR |
> > > > > @@ -1076,7 +1070,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
> > > > > int i, ret, recv_bytes;
> > > > > uint32_t status;
> > > > > int try, clock = 0;
> > > > > - bool has_aux_irq = HAS_AUX_IRQ(dev_priv);
> > > > > bool vdd;
> > > > >
> > > > > ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
> > > > > @@ -1131,7 +1124,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
> > > > >
> > > > > while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
> > > > > u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
> > > > > - has_aux_irq,
> > > > > send_bytes,
> > > > > aux_clock_divider);
> > > > >
> > > > > @@ -1148,7 +1140,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
> > > > > /* Send the command and wait for it to complete */
> > > > > I915_WRITE(ch_ctl, send_ctl);
> > > > >
> > > > > - status = intel_dp_aux_wait_done(intel_dp, has_aux_irq);
> > > > > + status = intel_dp_aux_wait_done(intel_dp);
> > > > >
> > > > > /* Clear done status and any errors */
> > > > > I915_WRITE(ch_ctl,
> > > > > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> > > > > index 2855363f5b6c..7ac91d5ee3fa 100644
> > > > > --- a/drivers/gpu/drm/i915/intel_drv.h
> > > > > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > > > > @@ -1138,7 +1138,6 @@ struct intel_dp {
> > > > > * register with to kick off an AUX transaction.
> > > > > */
> > > > > uint32_t (*get_aux_send_ctl)(struct intel_dp *dp,
> > > > > - bool has_aux_irq,
> > > > > int send_bytes,
> > > > > uint32_t aux_clock_divider);
> > > > >
> > > > > diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
> > > > > index db27f2faa1de..ee26f5f33b87 100644
> > > > > --- a/drivers/gpu/drm/i915/intel_psr.c
> > > > > +++ b/drivers/gpu/drm/i915/intel_psr.c
> > > > > @@ -373,7 +373,7 @@ static void hsw_psr_setup_aux(struct intel_dp *intel_dp)
> > > > > aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, 0);
> > > > >
> > > > > /* Start with bits set for DDI_AUX_CTL register */
> > > > > - aux_ctl = intel_dp->get_aux_send_ctl(intel_dp, 0, sizeof(aux_msg),
> > > > > + aux_ctl = intel_dp->get_aux_send_ctl(intel_dp, sizeof(aux_msg),
> > > > > aux_clock_divider);
> > > >
> > > > Hmm. What's the situation with the PSR stuff here?
> > >
> > > I hadn't notice this, thanks.
> > >
> > > I don't see why it would actually be correct though. It seems to be a
> > > bug since d4dcbdceabe4 ("drm/i915/psr: Use ->get_aux_send_ctl
> > > functions") when the rmw was removed (so whatever was on the register
> > > before get overwritten).
> >
> > Dunno why you think there's a bug. The problem I see with this patch is
> > that you're now setting the irq enable bit on the psr aux register.
> > Does that bit even exist? If so does it do what we want it to do?
>
> I was assuming they should be the same. Now I see the psr code path
> gets the bits for
> DDI_AUX_CTL and mask to use only the valid bits for EDP_PSR_AUX_CTL. Bit 28 will
> be left out regardless the return of get_aux_send_ctl()
OK. Seems to all check out. Pushed to dinq. Thanks for the patch.
--
Ville Syrjälä
Intel
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