On 11/3/2017 3:05 PM, Michal Wajdeczko wrote:
We unconditionally program GUC_SHIM_CONTROL register with
all expected bits, but in case of required workaround we
modify those bits by using additional READ/WRITE calls.
Lets prepare correct value for this register prior to
first register programming.

Signed-off-by: Michal Wajdeczko <michal.wajdec...@intel.com>
Cc: Chris Wilson <ch...@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahti...@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kam...@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kam...@intel.com>
As per bspec, WaDisableMinuteIaClockGating is applicable to SKL A0/B0 as well. Should fix for those platforms unless we dont want to carry early pre-production workarounds.
---
  drivers/gpu/drm/i915/i915_guc_reg.h |  7 -------
  drivers/gpu/drm/i915/intel_guc_fw.c | 19 +++++++++++++------
  2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_guc_reg.h 
b/drivers/gpu/drm/i915/i915_guc_reg.h
index 35cf991..bc1ae7d 100644
--- a/drivers/gpu/drm/i915/i915_guc_reg.h
+++ b/drivers/gpu/drm/i915/i915_guc_reg.h
@@ -102,13 +102,6 @@
  #define   GUC_ENABLE_MIA_CLOCK_GATING         (1<<15)
  #define   GUC_GEN10_SHIM_WC_ENABLE            (1<<21)
-#define GUC_SHIM_CONTROL_VALUE (GUC_DISABLE_SRAM_INIT_TO_ZEROES | \
-                                GUC_ENABLE_READ_CACHE_LOGIC            | \
-                                GUC_ENABLE_MIA_CACHING                 | \
-                                GUC_ENABLE_READ_CACHE_FOR_SRAM_DATA    | \
-                                GUC_ENABLE_READ_CACHE_FOR_WOPCM_DATA   | \
-                                GUC_ENABLE_MIA_CLOCK_GATING)
-
  #define GUC_SEND_INTERRUPT            _MMIO(0xc4c8)
  #define   GUC_SEND_TRIGGER              (1<<0)
diff --git a/drivers/gpu/drm/i915/intel_guc_fw.c b/drivers/gpu/drm/i915/intel_guc_fw.c
index 74a61fe..3f013f7 100644
--- a/drivers/gpu/drm/i915/intel_guc_fw.c
+++ b/drivers/gpu/drm/i915/intel_guc_fw.c
@@ -100,15 +100,22 @@ int intel_guc_fw_select(struct intel_guc *guc)
  static void guc_prepare_xfer(struct intel_guc *guc)
  {
        struct drm_i915_private *dev_priv = guc_to_i915(guc);
+       u32 shim_control_value;
- /* Enable MIA caching. GuC clock gating is disabled. */
-       I915_WRITE(GUC_SHIM_CONTROL, GUC_SHIM_CONTROL_VALUE);
+       /* Expected bits for normal operation */
+       shim_control_value = GUC_DISABLE_SRAM_INIT_TO_ZEROES |
+                            GUC_ENABLE_READ_CACHE_LOGIC |
+                            GUC_ENABLE_MIA_CACHING |
+                            GUC_ENABLE_READ_CACHE_FOR_SRAM_DATA |
+                            GUC_ENABLE_READ_CACHE_FOR_WOPCM_DATA |
+                            GUC_ENABLE_MIA_CLOCK_GATING;
/* WaDisableMinuteIaClockGating:bxt */
-       if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1)) {
-               I915_WRITE(GUC_SHIM_CONTROL, (I915_READ(GUC_SHIM_CONTROL) &
-                                             ~GUC_ENABLE_MIA_CLOCK_GATING));
-       }
+       if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_A1))
+               shim_control_value &= ~GUC_ENABLE_MIA_CLOCK_GATING;
+
+       /* Must program this register before loading the ucode with DMA */
+       I915_WRITE(GUC_SHIM_CONTROL, shim_control_value);
/* WaC6DisallowByGfxPause:bxt */
        if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_B0))

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to