From 2eb8e1a69d9f8cc9c0a75e327f854957224ba421 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Wed, 17 Mar 2021 18:40:11 -0500 Subject: [PATCH] drm/i915/gem: Drop relocation support on all new hardware (v6) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The Vulkan driver in Mesa for Intel hardware never uses relocations if it's running on a version of i915 that supports at least softpin which all versions of i915 supporting Gen12 do. On the OpenGL side, Gen12+ is only supported by iris which never uses relocations. The older i965 driver in Mesa does use relocations but it only supports Intel hardware through Gen11 and has been deprecated for all hardware Gen9+. The compute driver also never uses relocations. This only leaves the media driver which is supposed to be switching to softpin going forward. Making softpin a requirement for all future hardware seems reasonable. There is one piece of hardware enabled by default in i915: RKL which was enabled by e22fa6f0a976 which has not yet landed in drm-next so this almost but not really a userspace API change for RKL. If it becomes a problem, we can always add !IS_ROCKETLAKE(eb->i915) to the condition. Rejecting relocations starting with newer Gen12 platforms has the benefit that we don't have to bother supporting it on platforms with local memory. Given how much CPU touching of memory is required for relocations, not having to do so on platforms where not all memory is directly CPU-accessible carries significant advantages. v2 (Jason Ekstrand): - Allow TGL-LP platforms as they've already shipped v3 (Jason Ekstrand): - WARN_ON platforms with LMEM support in case the check is wrong v4 (Jason Ekstrand): - Call out Rocket Lake in the commit message v5 (Jason Ekstrand): - Drop the HAS_LMEM check as it's already covered by the version check v6 (Jason Ekstrand): - Move the check to eb_validate_vma() with all the other exec_object validation checks. Signed-off-by: Jason Ekstrand Reviewed-by: Zbigniew Kempczyński Reviewed-by: Maarten Lankhorst Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210317234014.2271006-3-jason@jlekstrand.net --- drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index cdb85c77837c..21676baca8f5 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -483,6 +483,13 @@ eb_validate_vma(struct i915_execbuffer *eb, struct drm_i915_gem_exec_object2 *entry, struct i915_vma *vma) { + /* Relocations are disallowed for all platforms after TGL-LP. This + * also covers all platforms with local memory. + */ + if (entry->relocation_count && + INTEL_GEN(eb->i915) >= 12 && !IS_TIGERLAKE(eb->i915)) + return -EINVAL; + if (unlikely(entry->flags & eb->invalid_flags)) return -EINVAL; -- 2.20.1