drm/xe: Clarify register types on PAT programming
authorLucas De Marchi <lucas.demarchi@intel.com>
Thu, 27 Apr 2023 22:32:50 +0000 (15:32 -0700)
committerRodrigo Vivi <rodrigo.vivi@intel.com>
Tue, 19 Dec 2023 23:32:21 +0000 (18:32 -0500)
Clarify a few things related to the PAT programming, particularly on
MTL:

- The register type doesn't change depending on the GT - what
  happens is that media GT writes to other set of registers that
  are not MCR
- Remove "UNICAST": otherwise it's confusing why it's not using
  MCR registers with the unicast function variant

Also, there isn't much reason to keep those parts as macros: promote
them to proper functions and let the compiler inline if it sees fit.

Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230427223256.1432787-5-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
drivers/gpu/drm/xe/xe_pat.c

index c2faf09..fcf6ae2 100644 (file)
@@ -62,31 +62,36 @@ static const u32 mtl_pat_table[] = {
        [4] = MTL_PAT_0_WB | MTL_3_COH_2W,
 };
 
-#define PROGRAM_PAT_UNICAST(gt, table) do { \
-       for (int i = 0; i < ARRAY_SIZE(table); i++) \
-               xe_mmio_write32(gt, _PAT_INDEX(i), table[i]); \
-} while (0)
+static void program_pat(struct xe_gt *gt, const u32 table[], int n_entries)
+{
+       for (int i = 0; i < n_entries; i++)
+               xe_mmio_write32(gt, _PAT_INDEX(i), table[i]);
+}
 
-#define PROGRAM_PAT_MCR(gt, table) do { \
-       for (int i = 0; i < ARRAY_SIZE(table); i++) \
-               xe_gt_mcr_multicast_write(gt, MCR_REG(_PAT_INDEX(i)), table[i]); \
-} while (0)
+static void program_pat_mcr(struct xe_gt *gt, const u32 table[], int n_entries)
+{
+       for (int i = 0; i < n_entries; i++)
+               xe_gt_mcr_multicast_write(gt, MCR_REG(_PAT_INDEX(i)), table[i]);
+}
 
 void xe_pat_init(struct xe_gt *gt)
 {
        struct xe_device *xe = gt_to_xe(gt);
 
        if (xe->info.platform == XE_METEORLAKE) {
+               /*
+                * SAMedia register offsets are adjusted by the write methods
+                * and they target registers that are not MCR, while for normal
+                * GT they are MCR
+                */
                if (xe_gt_is_media_type(gt))
-                       PROGRAM_PAT_UNICAST(gt, mtl_pat_table);
+                       program_pat(gt, mtl_pat_table, ARRAY_SIZE(mtl_pat_table));
                else
-                       PROGRAM_PAT_MCR(gt, mtl_pat_table);
-       } else if (xe->info.platform == XE_PVC) {
-               PROGRAM_PAT_MCR(gt, pvc_pat_table);
-       } else if (xe->info.platform == XE_DG2) {
-               PROGRAM_PAT_MCR(gt, pvc_pat_table);
+                       program_pat_mcr(gt, mtl_pat_table, ARRAY_SIZE(mtl_pat_table));
+       } else if (xe->info.platform == XE_PVC || xe->info.platform == XE_DG2) {
+               program_pat_mcr(gt, pvc_pat_table, ARRAY_SIZE(pvc_pat_table));
        } else if (GRAPHICS_VERx100(xe) <= 1210) {
-               PROGRAM_PAT_UNICAST(gt, tgl_pat_table);
+               program_pat(gt, tgl_pat_table, ARRAY_SIZE(tgl_pat_table));
        } else {
                /*
                 * Going forward we expect to need new PAT settings for most