Hi, Christian,
On Mon, 2022-02-07 at 12:41 +0100, Christian König wrote:
Am 07.02.22 um 10:37 schrieb Ramalingam C:
On flat-ccs capable platform we need to evict and resore the ccs data along with the corresponding main memory.
This ccs data can only be access through BLT engine through a special cmd ( )
To support above requirement of flat-ccs enabled i915 platforms this series adds new param called ccs_pages_needed to the ttm_tt_init(), to increase the ttm_tt->num_pages of system memory when the obj has the lmem placement possibility.
Well question is why isn't the buffer object allocated with the extra space in the first place?
That wastes precious VRAM. The extra space is needed only when the bo is evicted.
We've had a previous short disussion on this here: https://lists.freedesktop.org/archives/dri-devel/2021-August/321161.html
Thanks, Thomas
Regards, Christian.
This will be on top of the flat-ccs enabling series https://patchwork.freedesktop.org/series/95686/
For more about flat-ccs feature please have a look at https://patchwork.freedesktop.org/patch/471777/?series=95686&rev=5
Testing of the series is WIP and looking forward for the early review on the amendment to ttm_tt_init and the approach.
Ramalingam C (2): drm/i915/ttm: Add extra pages for handling ccs data drm/i915/migrate: Evict and restore the ccs data
drivers/gpu/drm/drm_gem_vram_helper.c | 2 +- drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 23 +- drivers/gpu/drm/i915/gt/intel_migrate.c | 283 +++++++++++-------
drivers/gpu/drm/qxl/qxl_ttm.c | 2 +- drivers/gpu/drm/ttm/ttm_agp_backend.c | 2 +- drivers/gpu/drm/ttm/ttm_tt.c | 12 +- drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c | 2 +- include/drm/ttm/ttm_tt.h | 4 +- 8 files changed, 191 insertions(+), 139 deletions(-)
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