diff options
Diffstat (limited to 'drivers/gpu/drm/xe/xe_device.c')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_device.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index e25c37ac7d14..0d57eea8f083 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -754,6 +754,55 @@ void xe_device_wmb(struct xe_device *xe) xe_mmio_write32(gt, SOFTWARE_FLAGS_SPR33, 0); } +/** + * xe_device_td_flush() - Flush transient L3 cache entries + * @xe: The device + * + * Display engine has direct access to memory and is never coherent with L3/L4 + * caches (or CPU caches), however KMD is responsible for specifically flushing + * transient L3 GPU cache entries prior to the flip sequence to ensure scanout + * can happen from such a surface without seeing corruption. + * + * Display surfaces can be tagged as transient by mapping it using one of the + * various L3:XD PAT index modes on Xe2. + * + * Note: On non-discrete xe2 platforms, like LNL, the entire L3 cache is flushed + * at the end of each submission via PIPE_CONTROL for compute/render, since SA + * Media is not coherent with L3 and we want to support render-vs-media + * usescases. For other engines like copy/blt the HW internally forces uncached + * behaviour, hence why we can skip the TDF on such platforms. + */ +void xe_device_td_flush(struct xe_device *xe) +{ + struct xe_gt *gt; + u8 id; + + if (!IS_DGFX(xe) || GRAPHICS_VER(xe) < 20) + return; + + for_each_gt(gt, xe, id) { + if (xe_gt_is_media_type(gt)) + continue; + + if (xe_force_wake_get(gt_to_fw(gt), XE_FW_GT)) + return; + + xe_mmio_write32(gt, XE2_TDF_CTRL, TRANSIENT_FLUSH_REQUEST); + /* + * FIXME: We can likely do better here with our choice of + * timeout. Currently we just assume the worst case, i.e. 150us, + * which is believed to be sufficient to cover the worst case + * scenario on current platforms if all cache entries are + * transient and need to be flushed.. + */ + if (xe_mmio_wait32(gt, XE2_TDF_CTRL, TRANSIENT_FLUSH_REQUEST, 0, + 150, NULL, false)) + xe_gt_err_once(gt, "TD flush timeout\n"); + + xe_force_wake_put(gt_to_fw(gt), XE_FW_GT); + } +} + u32 xe_device_ccs_bytes(struct xe_device *xe, u64 size) { return xe_device_has_flat_ccs(xe) ? |