drm/i915: implement WaIncreaseDefaultTLBEntries

WaIncreaseDefaultTLBEntries increases the number of TLB
entries available for GPGPU workloads and gives significant
( > 10% ) performance gain for some OCL benchmarks.
Put this in a new function that can be a place for
workarounds that are GT related but not required per ring.
This function is called on driver load and also after a
reset and on resume, so it is safe for workarounds that get
clobbered in these situations. This function currently has
just this one workaround.

v2: This was originally split into 3 patches but following
  review feedback was squashed into 1.
  I have not incorporated some style comments from Chris
  Wilson as I felt that after defining and intialising a
  temporary variable and then adding an additional if block
  to only write the register if the temporary variable had
  been set, this didn't really give a net gain.

v3: Resending in the hope that BAT will run

v4: Change subject line to trigger BAT (please!)

Signed-off-by: Tim Gore <tim.gore@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1454586574-2343-1-git-send-email-tim.gore@intel.com
This commit is contained in:
Tim Gore 2016-02-04 11:49:34 +00:00 committed by Tvrtko Ursulin
parent 58d4d32f43
commit d5165ebd52
2 changed files with 28 additions and 0 deletions

View file

@ -2132,6 +2132,25 @@ static void i915_address_space_init(struct i915_address_space *vm,
list_add_tail(&vm->global_link, &dev_priv->vm_list);
}
static void gtt_write_workarounds(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
/* This function is for gtt related workarounds. This function is
* called on driver load and after a GPU reset, so you can place
* workarounds here even if they get overwritten by GPU reset.
*/
/* WaIncreaseDefaultTLBEntries:chv,bdw,skl,bxt */
if (IS_BROADWELL(dev))
I915_WRITE(GEN8_L3_LRA_1_GPGPU, GEN8_L3_LRA_1_GPGPU_DEFAULT_VALUE_BDW);
else if (IS_CHERRYVIEW(dev))
I915_WRITE(GEN8_L3_LRA_1_GPGPU, GEN8_L3_LRA_1_GPGPU_DEFAULT_VALUE_CHV);
else if (IS_SKYLAKE(dev))
I915_WRITE(GEN8_L3_LRA_1_GPGPU, GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_SKL);
else if (IS_BROXTON(dev))
I915_WRITE(GEN8_L3_LRA_1_GPGPU, GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_BXT);
}
int i915_ppgtt_init(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@ -2148,6 +2167,8 @@ int i915_ppgtt_init(struct drm_device *dev, struct i915_hw_ppgtt *ppgtt)
int i915_ppgtt_init_hw(struct drm_device *dev)
{
gtt_write_workarounds(dev);
/* In the case of execlists, PPGTT is enabled by the context descriptor
* and the PDPs are contained within the context itself. We don't
* need to do anything here. */

View file

@ -8173,4 +8173,11 @@ enum skl_disp_power_wells {
#define GEN9_VEBOX_MOCS(i) _MMIO(0xcb00 + (i) * 4) /* Video MOCS registers */
#define GEN9_BLT_MOCS(i) _MMIO(0xcc00 + (i) * 4) /* Blitter MOCS registers */
/* gamt regs */
#define GEN8_L3_LRA_1_GPGPU _MMIO(0x4dd4)
#define GEN8_L3_LRA_1_GPGPU_DEFAULT_VALUE_BDW 0x67F1427F /* max/min for LRA1/2 */
#define GEN8_L3_LRA_1_GPGPU_DEFAULT_VALUE_CHV 0x5FF101FF /* max/min for LRA1/2 */
#define GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_SKL 0x67F1427F /* " " */
#define GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_BXT 0x5FF101FF /* " " */
#endif /* _I915_REG_H_ */