| Message ID | 20230310094544.3865-1-nirmoy.das@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] drm/i915/mtl: Disable stolen memory backed FB for A0 | expand |
On 10.03.2023 10:45, Nirmoy Das wrote: > Stolen memory is not usable for MTL A0 stepping beyond > certain access size and we have no control over userspace > access size of /dev/fb which can be backed by stolen memory. > So disable stolen memory backed fb by setting i915->dsm.usable_size > to zero. > > v2: remove hsdes reference and fix commit message(Andi) > > Cc: Matthew Auld <matthew.auld@intel.com> > Cc: Andi Shyti <andi.shyti@linux.intel.com> > Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> > Cc: Lucas De Marchi <lucas.demarchi@intel.com> > Signed-off-by: Nirmoy Das <nirmoy.das@intel.com> > Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com> Regards Andrzej > --- > drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c > index d8e06e783e30..bf0f0a5f2a5c 100644 > --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c > +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c > @@ -535,6 +535,15 @@ static int i915_gem_init_stolen(struct intel_memory_region *mem) > /* Basic memrange allocator for stolen space. */ > drm_mm_init(&i915->mm.stolen, 0, i915->dsm.usable_size); > > + /* > + * Access to stolen lmem beyond certain size for MTL A0 stepping > + * would crash the machine. Disable stolen lmem for userspace access > + * by setting usable_size to zero. > + */ > + if (IS_MTL_GRAPHICS_STEP(i915, M, STEP_A0, STEP_B0) || > + IS_MTL_GRAPHICS_STEP(i915, P, STEP_A0, STEP_B0)) > + i915->dsm.usable_size = 0; > + > return 0; > } >
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c index d8e06e783e30..bf0f0a5f2a5c 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c @@ -535,6 +535,15 @@ static int i915_gem_init_stolen(struct intel_memory_region *mem) /* Basic memrange allocator for stolen space. */ drm_mm_init(&i915->mm.stolen, 0, i915->dsm.usable_size); + /* + * Access to stolen lmem beyond certain size for MTL A0 stepping + * would crash the machine. Disable stolen lmem for userspace access + * by setting usable_size to zero. + */ + if (IS_MTL_GRAPHICS_STEP(i915, M, STEP_A0, STEP_B0) || + IS_MTL_GRAPHICS_STEP(i915, P, STEP_A0, STEP_B0)) + i915->dsm.usable_size = 0; + return 0; }