drm/xe/mocs: Allow odd number of entries on test

Refactor the mocs/l3cc kunit test to support odd number of entries. This
switches out from the "check the register value" approach to check the
entry value if it makes sense from the register read. This provides an
easier output to reason about and cross check with bspec.

Some code reordering and variable re-use was also done so the 2
functions follow more or less the same logic.
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240228061048.3661978-5-lucas.demarchi@intel.comSigned-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

drivers/gpu/drm/xe/tests/xe_mocs.c

@@ -39,30 +39,37 @@ static int live_mocs_init(struct live_mocs *arg, struct xe_gt *gt)
 static void read_l3cc_table(struct xe_gt *gt,
 			    const struct xe_mocs_info *info)
 {
+	struct kunit *test = xe_cur_kunit();
+	struct xe_device *xe = gt_to_xe(gt);
+	u32 l3cc, l3cc_expected;
 	unsigned int i;
-	u32 l3cc;
 	u32 reg_val;
 	u32 ret;
 
-	struct kunit *test = xe_cur_kunit();
-
 	ret = xe_force_wake_get(gt_to_fw(gt), XE_FW_GT);
 	KUNIT_ASSERT_EQ_MSG(test, ret, 0, "Forcewake Failed.\n");
-	mocs_dbg(&gt_to_xe(gt)->drm, "L3CC entries:%d\n", info->n_entries);
 
-	for (i = 0; i < (info->n_entries + 1) / 2; i++) {
-		l3cc = l3cc_combine(get_entry_l3cc(info, 2 * i),
-				    get_entry_l3cc(info, 2 * i + 1));
-
-		if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1250)
-			reg_val = xe_gt_mcr_unicast_read_any(gt, XEHP_LNCFCMOCS(i));
-		else
-			reg_val = xe_mmio_read32(gt, XELP_LNCFCMOCS(i));
-		mocs_dbg(&gt_to_xe(gt)->drm, "%d 0x%x 0x%x 0x%x\n", i,
-			 XELP_LNCFCMOCS(i).addr, reg_val, l3cc);
-		if (reg_val != l3cc)
-			KUNIT_FAIL(test, "l3cc reg 0x%x has incorrect val.\n",
-				   XELP_LNCFCMOCS(i).addr);
+	for (i = 0; i < info->n_entries; i++) {
+		if (!(i & 1)) {
+			if (GRAPHICS_VERx100(xe) >= 1250)
+				reg_val = xe_gt_mcr_unicast_read_any(gt, XEHP_LNCFCMOCS(i >> 1));
+			else
+				reg_val = xe_mmio_read32(gt, XELP_LNCFCMOCS(i >> 1));
+
+			mocs_dbg(&xe->drm, "reg_val=0x%x\n", reg_val);
+		} else {
+			/* Just re-use value read on previous iteration */
+			reg_val >>= 16;
+		}
+
+		l3cc_expected = get_entry_l3cc(info, i);
+		l3cc = reg_val & 0xffff;
+
+		mocs_dbg(&xe->drm, "[%u] expected=0x%x actual=0x%x\n",
+			 i, l3cc_expected, l3cc);
+
+		KUNIT_EXPECT_EQ_MSG(test, l3cc_expected, l3cc,
+				    "l3cc idx=%u has incorrect val.\n", i);
 	}
 	xe_force_wake_put(gt_to_fw(gt), XE_FW_GT);
 }
@@ -70,35 +77,35 @@ static void read_l3cc_table(struct xe_gt *gt,
 static void read_mocs_table(struct xe_gt *gt,
 			    const struct xe_mocs_info *info)
 {
+	struct kunit *test = xe_cur_kunit();
 	struct xe_device *xe = gt_to_xe(gt);
-
+	u32 mocs, mocs_expected;
 	unsigned int i;
-	u32 mocs;
 	u32 reg_val;
 	u32 ret;
 
-	struct kunit *test = xe_cur_kunit();
-
 	KUNIT_EXPECT_TRUE_MSG(test, info->unused_entries_index,
 			      "Unused entries index should have been defined\n");
 
 	ret = xe_force_wake_get(gt_to_fw(gt), XE_FW_GT);
 	KUNIT_ASSERT_EQ_MSG(test, ret, 0, "Forcewake Failed.\n");
-	mocs_dbg(&gt_to_xe(gt)->drm, "Global MOCS entries:%d\n", info->n_entries);
 
 	for (i = 0; i < info->n_entries; i++) {
-		mocs = get_entry_control(info, i);
-
-		if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1250)
+		if (GRAPHICS_VERx100(xe) >= 1250)
 			reg_val = xe_gt_mcr_unicast_read_any(gt, XEHP_GLOBAL_MOCS(i));
 		else
 			reg_val = xe_mmio_read32(gt, XELP_GLOBAL_MOCS(i));
-		mocs_dbg(&gt_to_xe(gt)->drm, "%d 0x%x 0x%x 0x%x\n", i,
-			 XELP_GLOBAL_MOCS(i).addr, reg_val, mocs);
-		if (reg_val != mocs)
-			KUNIT_FAIL(test, "mocs reg 0x%x has incorrect val.\n",
-				   XELP_GLOBAL_MOCS(i).addr);
+
+		mocs_expected = get_entry_control(info, i);
+		mocs = reg_val;
+
+		mocs_dbg(&xe->drm, "[%u] expected=0x%x actual=0x%x\n",
+			 i, mocs_expected, mocs);
+
+		KUNIT_EXPECT_EQ_MSG(test, mocs_expected, mocs,
+				    "mocs reg 0x%x has incorrect val.\n", i);
 	}
+
 	xe_force_wake_put(gt_to_fw(gt), XE_FW_GT);
 }