Re: [Intel-gfx] [PATCH] drm/i915: replace X86_FEATURE_PAT with pat_enabled()

On Wed, 2021-12-01 at 16:30 -0800, Lucas De Marchi wrote:

PAT can be disabled on boot with "nopat" in the command line. Replace one x86-ism with another, which is slightly more correct to prepare for supporting other architectures.

Reviewed-by: José Roberto de Souza jose.souza@intel.com

Cc: Matt Roper matthew.d.roper@intel.com Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com

---

drivers/gpu/drm/i915/gem/i915_gem_mman.c | 8 ++++---- drivers/gpu/drm/i915/gem/i915_gem_pages.c | 3 +-- 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 65fc6ff5f59d..c0c509e5c0ae 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -72,7 +72,7 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data, if (args->flags & ~(I915_MMAP_WC)) return -EINVAL;

• if (args->flags & I915_MMAP_WC && !boot_cpu_has(X86_FEATURE_PAT))

• if (args->flags & I915_MMAP_WC && !pat_enabled()) return -ENODEV;

  obj = i915_gem_object_lookup(file, args->handle);

@@ -736,7 +736,7 @@ i915_gem_dumb_mmap_offset(struct drm_file *file,

if (HAS_LMEM(to_i915(dev))) mmap_type = I915_MMAP_TYPE_FIXED;

• else if (boot_cpu_has(X86_FEATURE_PAT))

• else if (pat_enabled()) mmap_type = I915_MMAP_TYPE_WC; else if (!i915_ggtt_has_aperture(&to_i915(dev)->ggtt)) return -ENODEV;

@@ -792,7 +792,7 @@ i915_gem_mmap_offset_ioctl(struct drm_device *dev, void *data, break;

case I915_MMAP_OFFSET_WC:

• if (!boot_cpu_has(X86_FEATURE_PAT))
  

• if (!pat_enabled())
  return -ENODEV;
  

  type = I915_MMAP_TYPE_WC; break;

@@ -802,7 +802,7 @@ i915_gem_mmap_offset_ioctl(struct drm_device *dev, void *data, break;

case I915_MMAP_OFFSET_UC:

• if (!boot_cpu_has(X86_FEATURE_PAT))
  

• if (!pat_enabled())
  return -ENODEV;
  

  type = I915_MMAP_TYPE_UC; break;

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c index 49c6e55c68ce..89b70f5cde7a 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c @@ -424,8 +424,7 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, goto err_unpin; }

• if (GEM_WARN_ON(type == I915_MAP_WC &&
  

• 		!static_cpu_has(X86_FEATURE_PAT)))
  

• if (GEM_WARN_ON(type == I915_MAP_WC && !pat_enabled()))
  ptr = ERR_PTR(-ENODEV);
  

  else if (i915_gem_object_has_struct_page(obj)) ptr = i915_gem_object_map_page(obj, type);