github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-28 09:04:39 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/i915: drop one bit on the hw_id when using guc

Browse Source 
We currently using GuC as a proxy to the hardware. When Guc is used in
such mode, it consumes the bit 20 of the hw_id to indicate that the
workload was submitted by proxy.

So far we probably haven't seen the issue because we need to allocate
1048576+ contexts to hit this issue. Still, we should avoid allocating
the hw_id on that bit and restriction to bits [0:19] (i.e 20bits
instead of 21).

v2: Leave the max hw_id computation in i915_gem_context.c (Michel)

v3: Be consistent on if/else usage (Chris)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
BSpec: 1237
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180602112946.30803-2-lionel.g.landwerlin@intel.com
This commit is contained in:
Lionel Landwerlin 2018-06-02 12:29:45 +01:00
parent 30aacd3fe7
commit 218b500098
3 changed files with 14 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/gpu/drm/i915/i915_drv.h
View File

@ -1841,6 +1841,7 @@ struct drm_i915_private {
*/
struct ida hw_ida;
#define MAX_CONTEXT_HW_ID (1<<21) /* exclusive */
#define MAX_GUC_CONTEXT_HW_ID (1 << 20) /* exclusive */
#define GEN11_MAX_CONTEXT_HW_ID (1<<11) /* exclusive */
} contexts;

15
drivers/gpu/drm/i915/i915_gem_context.c
View File

@ -208,10 +208,19 @@ static int assign_hw_id(struct drm_i915_private *dev_priv, unsigned *out)
int ret;
unsigned int max;
if (INTEL_GEN(dev_priv) >= 11)
if (INTEL_GEN(dev_priv) >= 11) {
max = GEN11_MAX_CONTEXT_HW_ID;
else
max = MAX_CONTEXT_HW_ID;
} else {
/*
* When using GuC in proxy submission, GuC consumes the
* highest bit in the context id to indicate proxy submission.
*/
if (USES_GUC_SUBMISSION(dev_priv))
max = MAX_GUC_CONTEXT_HW_ID;
else
max = MAX_CONTEXT_HW_ID;
}
ret = ida_simple_get(&dev_priv->contexts.hw_ida,
0, max, GFP_KERNEL);

2
drivers/gpu/drm/i915/intel_lrc.c
View File

@ -200,7 +200,7 @@ static inline bool need_preempt(const struct intel_engine_cs *engine,
*
* bits 0-11: flags, GEN8_CTX_* (cached in ctx->desc_template)
* bits 12-31: LRCA, GTT address of (the HWSP of) this context
* bits 32-52: ctx ID, a globally unique tag
* bits 32-52: ctx ID, a globally unique tag (highest bit used by GuC)
* bits 53-54: mbz, reserved for use by hardware
* bits 55-63: group ID, currently unused and set to 0
*