Commit ef48715b authored by Lucas De Marchi's avatar Lucas De Marchi
Browse files

drm/xe/lrc: Use a temporary buffer for WA BB 



In case the BO is in iomem, we can't simply take the vaddr and write to
it. Instead, prepare a separate buffer that is later copied into io
memory. Right now it's just a few words that could be using
xe_map_write32(), but the intention is to grow the WA BB for other
uses.

Fixes: 82b98cad ("drm/xe: Add WA BB to capture active context utilization")
Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarUmesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Link: https://lore.kernel.org/r/20250604-wa-bb-fix-v1-1-0dfc5dafcef0@intel.com


Signed-off-by: default avatarLucas De Marchi <lucas.demarchi@intel.com>
parent 26ff87d2

drivers/gpu/drm/xe/xe_lrc.c

+20 −4
Original line number Diff line number Diff line
@@ -941,11 +941,18 @@ static void xe_lrc_finish(struct xe_lrc *lrc) 
 * store it in the PPHSWP.

 */

#define CONTEXT_ACTIVE 1ULL

static void xe_lrc_setup_utilization(struct xe_lrc *lrc)

static int xe_lrc_setup_utilization(struct xe_lrc *lrc)

{

	u32 *cmd;

	u32 *cmd, *buf = NULL;



	if (lrc->bb_per_ctx_bo->vmap.is_iomem) {

		buf = kmalloc(lrc->bb_per_ctx_bo->size, GFP_KERNEL);

		if (!buf)

			return -ENOMEM;

		cmd = buf;

	} else {

		cmd = lrc->bb_per_ctx_bo->vmap.vaddr;

	}



	*cmd++ = MI_STORE_REGISTER_MEM | MI_SRM_USE_GGTT | MI_SRM_ADD_CS_OFFSET;

	*cmd++ = ENGINE_ID(0).addr;
@@ -966,9 +973,16 @@ static void xe_lrc_setup_utilization(struct xe_lrc *lrc) 


	*cmd++ = MI_BATCH_BUFFER_END;



	if (buf) {

		xe_map_memcpy_to(gt_to_xe(lrc->gt), &lrc->bb_per_ctx_bo->vmap, 0,

				 buf, (cmd - buf) * sizeof(*cmd));

		kfree(buf);

	}



	xe_lrc_write_ctx_reg(lrc, CTX_BB_PER_CTX_PTR,

			     xe_bo_ggtt_addr(lrc->bb_per_ctx_bo) | 1);



	return 0;

}



#define PVC_CTX_ASID		(0x2e + 1)
@@ -1125,7 +1139,9 @@ static int xe_lrc_init(struct xe_lrc *lrc, struct xe_hw_engine *hwe, 
	map = __xe_lrc_start_seqno_map(lrc);

	xe_map_write32(lrc_to_xe(lrc), &map, lrc->fence_ctx.next_seqno - 1);



	xe_lrc_setup_utilization(lrc);

	err = xe_lrc_setup_utilization(lrc);

	if (err)

		goto err_lrc_finish;



	return 0;