From: Ville Syrjälä Date: Thu, 14 Sep 2017 15:17:31 +0000 (+0300) Subject: drm/i915: Don't rmw PIPESTAT enable bits X-Git-Tag: v4.19~298^2~46^2~1535 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6b12ca569bb2f864892c41dbbb0f88f3f9952bf3;p=platform%2Fkernel%2Flinux-rpi.git drm/i915: Don't rmw PIPESTAT enable bits i830 seems to occasionally forget the PIPESTAT enable bits when we read the register. These aren't the only registers on i830 that have problems with RMW, as reading the double buffered plane registers returns the latched value rather than the last written value. So something similar is perhaps going on with PIPESTAT. This corruption results on vblank interrupts occasionally turning off on their own, which leads to vblank timeouts and generally a stuck display subsystem. So let's not RMW the pipestat enable bits, and instead use the cached copy we have around. Cc: Imre Deak Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20170914151731.5034-1-ville.syrjala@linux.intel.com Reviewed-by: Imre Deak --- diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 0f26aa5..44f5569 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3313,6 +3313,8 @@ static inline bool intel_vgpu_active(struct drm_i915_private *dev_priv) return dev_priv->vgpu.active; } +u32 i915_pipestat_enable_mask(struct drm_i915_private *dev_priv, + enum pipe pipe); void i915_enable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe, u32 status_mask); diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index af82bd7..6a07ef3 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -567,62 +567,16 @@ void ibx_display_interrupt_update(struct drm_i915_private *dev_priv, POSTING_READ(SDEIMR); } -static void -__i915_enable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe, - u32 enable_mask, u32 status_mask) +u32 i915_pipestat_enable_mask(struct drm_i915_private *dev_priv, + enum pipe pipe) { - i915_reg_t reg = PIPESTAT(pipe); - u32 pipestat = I915_READ(reg) & PIPESTAT_INT_ENABLE_MASK; - - lockdep_assert_held(&dev_priv->irq_lock); - WARN_ON(!intel_irqs_enabled(dev_priv)); - - if (WARN_ONCE(enable_mask & ~PIPESTAT_INT_ENABLE_MASK || - status_mask & ~PIPESTAT_INT_STATUS_MASK, - "pipe %c: enable_mask=0x%x, status_mask=0x%x\n", - pipe_name(pipe), enable_mask, status_mask)) - return; - - if ((pipestat & enable_mask) == enable_mask) - return; - - dev_priv->pipestat_irq_mask[pipe] |= status_mask; - - /* Enable the interrupt, clear any pending status */ - pipestat |= enable_mask | status_mask; - I915_WRITE(reg, pipestat); - POSTING_READ(reg); -} - -static void -__i915_disable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe, - u32 enable_mask, u32 status_mask) -{ - i915_reg_t reg = PIPESTAT(pipe); - u32 pipestat = I915_READ(reg) & PIPESTAT_INT_ENABLE_MASK; + u32 status_mask = dev_priv->pipestat_irq_mask[pipe]; + u32 enable_mask = status_mask << 16; lockdep_assert_held(&dev_priv->irq_lock); - WARN_ON(!intel_irqs_enabled(dev_priv)); - - if (WARN_ONCE(enable_mask & ~PIPESTAT_INT_ENABLE_MASK || - status_mask & ~PIPESTAT_INT_STATUS_MASK, - "pipe %c: enable_mask=0x%x, status_mask=0x%x\n", - pipe_name(pipe), enable_mask, status_mask)) - return; - - if ((pipestat & enable_mask) == 0) - return; - - dev_priv->pipestat_irq_mask[pipe] &= ~status_mask; - - pipestat &= ~enable_mask; - I915_WRITE(reg, pipestat); - POSTING_READ(reg); -} -static u32 vlv_get_pipestat_enable_mask(struct drm_device *dev, u32 status_mask) -{ - u32 enable_mask = status_mask << 16; + if (INTEL_GEN(dev_priv) < 5) + goto out; /* * On pipe A we don't support the PSR interrupt yet, @@ -645,35 +599,59 @@ static u32 vlv_get_pipestat_enable_mask(struct drm_device *dev, u32 status_mask) if (status_mask & SPRITE1_FLIP_DONE_INT_STATUS_VLV) enable_mask |= SPRITE1_FLIP_DONE_INT_EN_VLV; +out: + WARN_ONCE(enable_mask & ~PIPESTAT_INT_ENABLE_MASK || + status_mask & ~PIPESTAT_INT_STATUS_MASK, + "pipe %c: enable_mask=0x%x, status_mask=0x%x\n", + pipe_name(pipe), enable_mask, status_mask); + return enable_mask; } -void -i915_enable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe, - u32 status_mask) +void i915_enable_pipestat(struct drm_i915_private *dev_priv, + enum pipe pipe, u32 status_mask) { + i915_reg_t reg = PIPESTAT(pipe); u32 enable_mask; - if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) - enable_mask = vlv_get_pipestat_enable_mask(&dev_priv->drm, - status_mask); - else - enable_mask = status_mask << 16; - __i915_enable_pipestat(dev_priv, pipe, enable_mask, status_mask); + WARN_ONCE(status_mask & ~PIPESTAT_INT_STATUS_MASK, + "pipe %c: status_mask=0x%x\n", + pipe_name(pipe), status_mask); + + lockdep_assert_held(&dev_priv->irq_lock); + WARN_ON(!intel_irqs_enabled(dev_priv)); + + if ((dev_priv->pipestat_irq_mask[pipe] & status_mask) == status_mask) + return; + + dev_priv->pipestat_irq_mask[pipe] |= status_mask; + enable_mask = i915_pipestat_enable_mask(dev_priv, pipe); + + I915_WRITE(reg, enable_mask | status_mask); + POSTING_READ(reg); } -void -i915_disable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe, - u32 status_mask) +void i915_disable_pipestat(struct drm_i915_private *dev_priv, + enum pipe pipe, u32 status_mask) { + i915_reg_t reg = PIPESTAT(pipe); u32 enable_mask; - if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) - enable_mask = vlv_get_pipestat_enable_mask(&dev_priv->drm, - status_mask); - else - enable_mask = status_mask << 16; - __i915_disable_pipestat(dev_priv, pipe, enable_mask, status_mask); + WARN_ONCE(status_mask & ~PIPESTAT_INT_STATUS_MASK, + "pipe %c: status_mask=0x%x\n", + pipe_name(pipe), status_mask); + + lockdep_assert_held(&dev_priv->irq_lock); + WARN_ON(!intel_irqs_enabled(dev_priv)); + + if ((dev_priv->pipestat_irq_mask[pipe] & status_mask) == 0) + return; + + dev_priv->pipestat_irq_mask[pipe] &= ~status_mask; + enable_mask = i915_pipestat_enable_mask(dev_priv, pipe); + + I915_WRITE(reg, enable_mask | status_mask); + POSTING_READ(reg); } /** @@ -1775,7 +1753,7 @@ static void i9xx_pipestat_irq_ack(struct drm_i915_private *dev_priv, for_each_pipe(dev_priv, pipe) { i915_reg_t reg; - u32 mask, iir_bit = 0; + u32 status_mask, enable_mask, iir_bit = 0; /* * PIPESTAT bits get signalled even when the interrupt is @@ -1786,7 +1764,7 @@ static void i9xx_pipestat_irq_ack(struct drm_i915_private *dev_priv, */ /* fifo underruns are filterered in the underrun handler. */ - mask = PIPE_FIFO_UNDERRUN_STATUS; + status_mask = PIPE_FIFO_UNDERRUN_STATUS; switch (pipe) { case PIPE_A: @@ -1800,21 +1778,20 @@ static void i9xx_pipestat_irq_ack(struct drm_i915_private *dev_priv, break; } if (iir & iir_bit) - mask |= dev_priv->pipestat_irq_mask[pipe]; + status_mask |= dev_priv->pipestat_irq_mask[pipe]; - if (!mask) + if (!status_mask) continue; reg = PIPESTAT(pipe); - mask |= PIPESTAT_INT_ENABLE_MASK; - pipe_stats[pipe] = I915_READ(reg) & mask; + pipe_stats[pipe] = I915_READ(reg) & status_mask; + enable_mask = i915_pipestat_enable_mask(dev_priv, pipe); /* * Clear the PIPE*STAT regs before the IIR */ - if (pipe_stats[pipe] & (PIPE_FIFO_UNDERRUN_STATUS | - PIPESTAT_INT_STATUS_MASK)) - I915_WRITE(reg, pipe_stats[pipe]); + if (pipe_stats[pipe]) + I915_WRITE(reg, enable_mask | pipe_stats[pipe]); } spin_unlock(&dev_priv->irq_lock); } diff --git a/drivers/gpu/drm/i915/intel_fifo_underrun.c b/drivers/gpu/drm/i915/intel_fifo_underrun.c index 0468960..77c123c 100644 --- a/drivers/gpu/drm/i915/intel_fifo_underrun.c +++ b/drivers/gpu/drm/i915/intel_fifo_underrun.c @@ -88,14 +88,15 @@ static void i9xx_check_fifo_underruns(struct intel_crtc *crtc) { struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); i915_reg_t reg = PIPESTAT(crtc->pipe); - u32 pipestat = I915_READ(reg) & 0xffff0000; + u32 enable_mask; lockdep_assert_held(&dev_priv->irq_lock); - if ((pipestat & PIPE_FIFO_UNDERRUN_STATUS) == 0) + if ((I915_READ(reg) & PIPE_FIFO_UNDERRUN_STATUS) == 0) return; - I915_WRITE(reg, pipestat | PIPE_FIFO_UNDERRUN_STATUS); + enable_mask = i915_pipestat_enable_mask(dev_priv, crtc->pipe); + I915_WRITE(reg, enable_mask | PIPE_FIFO_UNDERRUN_STATUS); POSTING_READ(reg); trace_intel_cpu_fifo_underrun(dev_priv, crtc->pipe); @@ -108,15 +109,16 @@ static void i9xx_set_fifo_underrun_reporting(struct drm_device *dev, { struct drm_i915_private *dev_priv = to_i915(dev); i915_reg_t reg = PIPESTAT(pipe); - u32 pipestat = I915_READ(reg) & 0xffff0000; lockdep_assert_held(&dev_priv->irq_lock); if (enable) { - I915_WRITE(reg, pipestat | PIPE_FIFO_UNDERRUN_STATUS); + u32 enable_mask = i915_pipestat_enable_mask(dev_priv, pipe); + + I915_WRITE(reg, enable_mask | PIPE_FIFO_UNDERRUN_STATUS); POSTING_READ(reg); } else { - if (old && pipestat & PIPE_FIFO_UNDERRUN_STATUS) + if (old && I915_READ(reg) & PIPE_FIFO_UNDERRUN_STATUS) DRM_ERROR("pipe %c underrun\n", pipe_name(pipe)); } }