drm/xe/xe2: Extend reserved stolen sizes

For xe2, besides the previous sizes, the reserved portion of stolen can
also have 16MB and 32MB.

Bspec: 53148
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230929044959.3149265-1-lucas.demarchi@intel.comSigned-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/regs/xe_regs.h

@@ -82,7 +82,7 @@
 #define GSMBASE					XE_REG(0x108100)
 
 #define STOLEN_RESERVED				XE_REG(0x1082c0)
-#define   WOPCM_SIZE_MASK			REG_GENMASK64(8, 7)
+#define   WOPCM_SIZE_MASK			REG_GENMASK64(9, 7)
 
 #define MTL_RP_STATE_CAP			XE_REG(0x138000)
 

drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c

@@ -86,6 +86,29 @@ static s64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr)
 	return ALIGN_DOWN(stolen_size, SZ_1M);
 }
 
+static u32 get_wopcm_size(struct xe_device *xe)
+{
+	u32 wopcm_size;
+	u64 val;
+
+	val = xe_mmio_read64_2x32(xe_root_mmio_gt(xe), STOLEN_RESERVED);
+	val = REG_FIELD_GET64(WOPCM_SIZE_MASK, val);
+
+	switch (val) {
+	case 0x5 ... 0x6:
+		val--;
+		fallthrough;
+	case 0x0 ... 0x3:
+		wopcm_size = (1U << val) * SZ_1M;
+		break;
+	default:
+		WARN(1, "Missing case wopcm_size=%llx\n", val);
+		wopcm_size = 0;
+	}
+
+	return wopcm_size;
+}
+
 static u32 detect_bar2_integrated(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr)
 {
 	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
@@ -125,10 +148,11 @@ static u32 detect_bar2_integrated(struct xe_device *xe, struct xe_ttm_stolen_mgr
 	}
 
 	/* Carve out the top of DSM as it contains the reserved WOPCM region */
-	wopcm_size = REG_FIELD_GET64(WOPCM_SIZE_MASK,
-				     xe_mmio_read64_2x32(xe_root_mmio_gt(xe),
-							 STOLEN_RESERVED));
-	stolen_size -= (1U << wopcm_size) * SZ_1M;
+	wopcm_size = get_wopcm_size(xe);
+	if (drm_WARN_ON(&xe->drm, !wopcm_size))
+		return 0;
+
+	stolen_size -= wopcm_size;
 
 	if (drm_WARN_ON(&xe->drm, stolen_size + SZ_8M > pci_resource_len(pdev, 2)))
 		return 0;