From b20e3cfe4b7dc62869a1f7e25d910a039c9aeb15 Mon Sep 17 00:00:00 2001 From: Dave Gordon Date: Mon, 12 Sep 2016 21:19:35 +0100 Subject: [PATCH] drm/i915: clarify PMINTRMSK/pm_intr_keep usage No functional changes; just renaming a bit, tweaking a datatype, prettifying layout, and adding comments, in particular in the GuC setup code that touches this data. Signed-off-by: Dave Gordon Link: http://patchwork.freedesktop.org/patch/msgid/1473711577-11454-2-git-send-email-david.s.gordon@intel.com Reviewed-by: Tvrtko Ursulin Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_irq.c | 4 ++-- drivers/gpu/drm/i915/i915_reg.h | 2 +- drivers/gpu/drm/i915/intel_guc_loader.c | 27 +++++++++++++++++++------ 4 files changed, 25 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 1e2dda88a483..d01a50e8e57c 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1184,6 +1184,7 @@ struct intel_gen6_power_mgmt { bool interrupts_enabled; u32 pm_iir; + /* PM interrupt bits that should never be masked */ u32 pm_intr_keep; /* Frequencies are stored in potentially platform dependent multiples. diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 8462817a7dae..c128fdbd24e4 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -371,7 +371,7 @@ void gen6_disable_rps_interrupts(struct drm_i915_private *dev_priv) spin_lock_irq(&dev_priv->irq_lock); dev_priv->rps.interrupts_enabled = false; - I915_WRITE(GEN6_PMINTRMSK, gen6_sanitize_rps_pm_mask(dev_priv, ~0)); + I915_WRITE(GEN6_PMINTRMSK, gen6_sanitize_rps_pm_mask(dev_priv, ~0u)); __gen6_disable_pm_irq(dev_priv, dev_priv->pm_rps_events); I915_WRITE(gen6_pm_ier(dev_priv), I915_READ(gen6_pm_ier(dev_priv)) & @@ -4500,7 +4500,7 @@ void intel_irq_init(struct drm_i915_private *dev_priv) dev_priv->rps.pm_intr_keep |= GEN6_PM_RP_UP_EI_EXPIRED; if (INTEL_INFO(dev_priv)->gen >= 8) - dev_priv->rps.pm_intr_keep |= GEN8_PMINTR_REDIRECT_TO_NON_DISP; + dev_priv->rps.pm_intr_keep |= GEN8_PMINTR_REDIRECT_TO_GUC; INIT_DELAYED_WORK(&dev_priv->gpu_error.hangcheck_work, i915_hangcheck_elapsed); diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index a29d707f0932..70d96162def6 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -7067,7 +7067,7 @@ enum { #define VLV_RCEDATA _MMIO(0xA0BC) #define GEN6_RC6pp_THRESHOLD _MMIO(0xA0C0) #define GEN6_PMINTRMSK _MMIO(0xA168) -#define GEN8_PMINTR_REDIRECT_TO_NON_DISP (1<<31) +#define GEN8_PMINTR_REDIRECT_TO_GUC (1<<31) #define GEN8_MISC_CTRL0 _MMIO(0xA180) #define VLV_PWRDWNUPCTL _MMIO(0xA294) #define GEN9_MEDIA_PG_IDLE_HYSTERESIS _MMIO(0xA0C4) diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c index 853928f21596..00217481f1fa 100644 --- a/drivers/gpu/drm/i915/intel_guc_loader.c +++ b/drivers/gpu/drm/i915/intel_guc_loader.c @@ -134,13 +134,28 @@ static void direct_interrupts_to_guc(struct drm_i915_private *dev_priv) I915_WRITE(GUC_WD_VECS_IER, ~irqs); /* - * If GuC has routed PM interrupts to itself, don't keep it. - * and keep other interrupts those are unmasked by GuC. - */ + * The REDIRECT_TO_GUC bit of the PMINTRMSK register directs all + * (unmasked) PM interrupts to the GuC. All other bits of this + * register *disable* generation of a specific interrupt. + * + * 'pm_intr_keep' indicates bits that are NOT to be set when + * writing to the PM interrupt mask register, i.e. interrupts + * that must not be disabled. + * + * If the GuC is handling these interrupts, then we must not let + * the PM code disable ANY interrupt that the GuC is expecting. + * So for each ENABLED (0) bit in this register, we must SET the + * bit in pm_intr_keep so that it's left enabled for the GuC. + * + * OTOH the REDIRECT_TO_GUC bit is initially SET in pm_intr_keep + * (so interrupts go to the DISPLAY unit at first); but here we + * need to CLEAR that bit, which will result in the register bit + * being left SET! + */ tmp = I915_READ(GEN6_PMINTRMSK); - if (tmp & GEN8_PMINTR_REDIRECT_TO_NON_DISP) { - dev_priv->rps.pm_intr_keep |= ~(tmp & ~GEN8_PMINTR_REDIRECT_TO_NON_DISP); - dev_priv->rps.pm_intr_keep &= ~GEN8_PMINTR_REDIRECT_TO_NON_DISP; + if (tmp & GEN8_PMINTR_REDIRECT_TO_GUC) { + dev_priv->rps.pm_intr_keep |= ~tmp; + dev_priv->rps.pm_intr_keep &= ~GEN8_PMINTR_REDIRECT_TO_GUC; } } -- 2.30.2