Hey, Den 2024-08-26 kl. 21:30, skrev Matthew Brost: > On Mon, Aug 26, 2024 at 07:01:16PM +0200, Maarten Lankhorst wrote: >> For CCS formats on affected platforms, CCS can be used freely, but >> display engine requires a multiple of 64k physical pages. No other >> changes are needed. >> >> At the BO creation time we don't know if the BO will be used for CCS >> or not. If the scanout flag is set, and the BO is a multiple of 64k, >> we take the safe route and force the physical alignment of 64k pages. >> >> If the BO is not a multiple of 64k, or the scanout flag was not set >> at BO creation, we reject it for usage as CCS in display. The physical >> pages are likely not aligned correctly, and this will cause corruption >> when used as FB. >> >> The scanout flag and size being a multiple of 64k are used together >> to enforce 64k physical placement. >> >> VM_BIND is completely unaffected, mappings to a VM can still be aligned >> to 4k, just like for normal buffers. >> >> Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski@xxxxxxxxx> >> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> >> Cc: Matthew Auld <matthew.auld@xxxxxxxxx> >> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> >> Cc: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx> >> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> >> Cc: Juha-Pekka Heikkilä <juha-pekka.heikkila@xxxxxxxxx> >> --- >> drivers/gpu/drm/xe/display/intel_fb_bo.c | 9 +++++++++ >> drivers/gpu/drm/xe/xe_bo.c | 7 +++++++ >> drivers/gpu/drm/xe/xe_vm.c | 11 ++++++++++- >> 3 files changed, 26 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/xe/display/intel_fb_bo.c b/drivers/gpu/drm/xe/display/intel_fb_bo.c >> index f835492f73fb4..63ce97cc4cfef 100644 >> --- a/drivers/gpu/drm/xe/display/intel_fb_bo.c >> +++ b/drivers/gpu/drm/xe/display/intel_fb_bo.c >> @@ -7,6 +7,7 @@ >> #include <drm/ttm/ttm_bo.h> >> >> #include "intel_display_types.h" >> +#include "intel_fb.h" >> #include "intel_fb_bo.h" >> #include "xe_bo.h" >> >> @@ -28,6 +29,14 @@ int intel_fb_bo_framebuffer_init(struct intel_framebuffer *intel_fb, >> struct xe_device *xe = to_xe_device(bo->ttm.base.dev); >> int ret; >> >> + /* >> + * Some modifiers require physical alignment of 64KiB VRAM pages; >> + * require that the BO in those cases is created correctly. >> + */ >> + if (XE_IOCTL_DBG(xe, intel_fb_needs_64k_phys(mode_cmd->modifier[0]) && >> + !(bo->flags & XE_BO_FLAG_NEEDS_64K))) >> + return -EINVAL; > > I don't think this is correct use of this macro as XE_BO_FLAG_NEEDS_64K > is an internal flag we set and typically this macro is used to santize > user input. An assert here or WARN would make more sense. Ideally we'd use 'is bo created as scanout', but that flag can be set by fb_init too, so if the BO was used for normal 4-tiled before, then as CCS it would pass when it wouldn't be valid. I could change it to bo_created_with_scanout_flag_on_64k_platform inline, but I doubt that's more readable. :) Cheers, ~Maarten
