From 1629224324b6cab6f7f96e839c9b57b74cfd8349 Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Wed, 30 Oct 2019 17:33:20 +0000 Subject: drm/i915/lmem: add the fake lmem region Intended for upstream testing so that we can still exercise the LMEM plumbing and !i915_ggtt_has_aperture paths. Smoke tested on Skull Canyon device. This works by allocating an intel_memory_region for a reserved portion of system memory, which we treat like LMEM. For the LMEMBAR we steal the aperture and 1:1 it map to the stolen region. To enable simply set the i915 modparam fake_lmem_start= on the kernel cmdline with the start of reserved region(see memmap=). The size of the region we can use is determined by the size of the mappable aperture, so the size of reserved region should be >= mappable_end. For now we only enable for the selftests. Depends on CONFIG_DRM_I915_UNSTABLE being enabled. eg. memmap=2G$16G i915.fake_lmem_start=0x400000000 v2: make fake_lmem_start an i915 modparam Signed-off-by: Matthew Auld Cc: Joonas Lahtinen Cc: Abdiel Janulgue Cc: Arkadiusz Hiler Cc: Chris Wilson Reviewed-by: Chris Wilson Signed-off-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20191030173320.8850-1-matthew.auld@intel.com --- drivers/gpu/drm/i915/i915_params.h | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/gpu/drm/i915/i915_params.h') diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h index a276317ad74b..31b88f297fbc 100644 --- a/drivers/gpu/drm/i915/i915_params.h +++ b/drivers/gpu/drm/i915/i915_params.h @@ -66,6 +66,7 @@ struct drm_printer; param(int, fastboot, -1) \ param(int, enable_dpcd_backlight, 0) \ param(char *, force_probe, CONFIG_DRM_I915_FORCE_PROBE) \ + param(unsigned long, fake_lmem_start, 0) \ /* leave bools at the end to not create holes */ \ param(bool, alpha_support, IS_ENABLED(CONFIG_DRM_I915_ALPHA_SUPPORT)) \ param(bool, enable_hangcheck, true) \ -- cgit