diff options
| author | Matt Roper <matthew.d.roper@intel.com> | 2023-03-29 20:33:32 +0300 |
|---|---|---|
| committer | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2023-12-20 02:30:26 +0300 |
| commit | 681818fdb97de821cc1ee6b81c7a09f3ef8fc96d (patch) | |
| tree | 354f9e01bb464e14dd2a907cb870be6c06cec03e /drivers/gpu/drm/xe/xe_bb.c | |
| parent | 3d4451d30f36ffe21f8c5eea7db9678330ee83c4 (diff) | |
| download | linux-681818fdb97de821cc1ee6b81c7a09f3ef8fc96d.tar.xz | |
drm/xe: Include hardware prefetch buffer in batchbuffer allocations
The hardware prefetches several cachelines of data from batchbuffers
before they are parsed. This prefetching only stops when the parser
encounters an MI_BATCH_BUFFER_END instruction (or a nested
MI_BATCH_BUFFER_START), so we must ensure that there is enough padding
at the end of the batchbuffer to prevent the prefetcher from running
past the end of the allocation and potentially faulting.
Bspec: 45717
Link: https://lore.kernel.org/r/20230329173334.4015124-2-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Diffstat (limited to 'drivers/gpu/drm/xe/xe_bb.c')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_bb.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/gpu/drm/xe/xe_bb.c b/drivers/gpu/drm/xe/xe_bb.c index 5b24018e2a80..f326f117ba3b 100644 --- a/drivers/gpu/drm/xe/xe_bb.c +++ b/drivers/gpu/drm/xe/xe_bb.c @@ -8,11 +8,26 @@ #include "regs/xe_gpu_commands.h" #include "xe_device.h" #include "xe_engine_types.h" +#include "xe_gt.h" #include "xe_hw_fence.h" #include "xe_sa.h" #include "xe_sched_job.h" #include "xe_vm_types.h" +static int bb_prefetch(struct xe_gt *gt) +{ + struct xe_device *xe = gt->xe; + + if (GRAPHICS_VERx100(xe) >= 1250 && !xe_gt_is_media_type(gt)) + /* + * RCS and CCS require 1K, although other engines would be + * okay with 512. + */ + return SZ_1K; + else + return SZ_512; +} + struct xe_bb *xe_bb_new(struct xe_gt *gt, u32 dwords, bool usm) { struct xe_bb *bb = kmalloc(sizeof(*bb), GFP_KERNEL); @@ -21,8 +36,14 @@ struct xe_bb *xe_bb_new(struct xe_gt *gt, u32 dwords, bool usm) if (!bb) return ERR_PTR(-ENOMEM); - bb->bo = xe_sa_bo_new(!usm ? >->kernel_bb_pool : - >->usm.bb_pool, 4 * dwords + 4); + /* + * We need to allocate space for the requested number of dwords, + * one additional MI_BATCH_BUFFER_END dword, and additional buffer + * space to accomodate the platform-specific hardware prefetch + * requirements. + */ + bb->bo = xe_sa_bo_new(!usm ? >->kernel_bb_pool : >->usm.bb_pool, + 4 * (dwords + 1) + bb_prefetch(gt)); if (IS_ERR(bb->bo)) { err = PTR_ERR(bb->bo); goto err; |