drm/xe: Generalize wa bb emission code

Generalize the wa bb emission by splitting it into three phases - setup,
emit and finish, and extract setup and finish steps into helpers.

This will enable using the same infrastructure for emitting the indirect
context workarounds.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250711160153.49833-2-tvrtko.ursulin@igalia.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

diff --git a/drivers/gpu/drm/xe/xe_lrc.c b/drivers/gpu/drm/xe/xe_lrc.c
index d2ad8fe737eb383e1f3326854a538346854be319..2385e22437b32b5ddcfd0fdd493a204965103420 100644 (file)
--- a/drivers/gpu/drm/xe/xe_lrc.c
+++ b/drivers/gpu/drm/xe/xe_lrc.c
@@ -972,32 +972,36 @@ static ssize_t wa_bb_setup_utilization(struct xe_lrc *lrc, struct xe_hw_engine *
        return cmd - batch;
 }
 
-struct wa_bb_setup {
+struct bo_setup {
        ssize_t (*setup)(struct xe_lrc *lrc, struct xe_hw_engine *hwe,
                         u32 *batch, size_t max_size);
 };
 
-static int setup_wa_bb(struct xe_lrc *lrc, struct xe_hw_engine *hwe)
+static u32 *setup_bo(struct xe_lrc *lrc,
+                    struct xe_hw_engine *hwe,
+                    const size_t max_size,
+                    unsigned int offset,
+                    const struct bo_setup *funcs,
+                    unsigned int num_funcs,
+                    u32 **free)
 {
-       const size_t max_size = LRC_WA_BB_SIZE;
-       static const struct wa_bb_setup funcs[] = {
-               { .setup = wa_bb_setup_utilization },
-       };
-       ssize_t remain;
        u32 *cmd, *buf = NULL;
+       ssize_t remain;
 
        if (lrc->bo->vmap.is_iomem) {
                buf = kmalloc(max_size, GFP_KERNEL);
                if (!buf)
-                       return -ENOMEM;
+                       return ERR_PTR(-ENOMEM);
                cmd = buf;
+               *free = buf;
        } else {
-               cmd = lrc->bo->vmap.vaddr + __xe_lrc_wa_bb_offset(lrc);
+               cmd = lrc->bo->vmap.vaddr + offset;
+               *free = NULL;
        }
 
        remain = max_size / sizeof(*cmd);
 
-       for (size_t i = 0; i < ARRAY_SIZE(funcs); i++) {
+       for (size_t i = 0; i < num_funcs; i++) {
                ssize_t len = funcs[i].setup(lrc, hwe, cmd, remain);
 
                remain -= len;
@@ -1012,23 +1016,45 @@ static int setup_wa_bb(struct xe_lrc *lrc, struct xe_hw_engine *hwe)
                cmd += len;
        }
 
+       return cmd;
+
+fail:
+       kfree(buf);
+       return ERR_PTR(-ENOSPC);
+}
+
+static void finish_bo(struct xe_lrc *lrc, unsigned int offset, u32 *cmd,
+                     u32 *free)
+{
+       if (!free)
+               return;
+
+       xe_map_memcpy_to(gt_to_xe(lrc->gt), &lrc->bo->vmap, offset, free,
+                        (cmd - free) * sizeof(*cmd));
+       kfree(free);
+}
+
+static int setup_wa_bb(struct xe_lrc *lrc, struct xe_hw_engine *hwe)
+{
+       static const struct bo_setup funcs[] = {
+               { .setup = wa_bb_setup_utilization },
+       };
+       unsigned int offset = __xe_lrc_wa_bb_offset(lrc);
+       u32 *cmd, *buf = NULL;
+
+       cmd = setup_bo(lrc, hwe, LRC_WA_BB_SIZE, offset, funcs,
+                      ARRAY_SIZE(funcs), &buf);
+       if (IS_ERR(cmd))
+               return PTR_ERR(cmd);
+
        *cmd++ = MI_BATCH_BUFFER_END;
 
-       if (buf) {
-               xe_map_memcpy_to(gt_to_xe(lrc->gt), &lrc->bo->vmap,
-                                __xe_lrc_wa_bb_offset(lrc), buf,
-                                (cmd - buf) * sizeof(*cmd));
-               kfree(buf);
-       }
+       finish_bo(lrc, offset, cmd, buf);
 
-       xe_lrc_write_ctx_reg(lrc, CTX_BB_PER_CTX_PTR, xe_bo_ggtt_addr(lrc->bo) +
-                            __xe_lrc_wa_bb_offset(lrc) + 1);
+       xe_lrc_write_ctx_reg(lrc, CTX_BB_PER_CTX_PTR,
+                            xe_bo_ggtt_addr(lrc->bo) + offset + 1);
 
        return 0;
-
-fail:
-       kfree(buf);
-       return -ENOSPC;
 }
 
 #define PVC_CTX_ASID           (0x2e + 1)