drm/ast: Put AST_DRAM_ constants into enum ast_dram_layout

The AST_DRAM_ constants belong together, so put them in an enum
type. Rename type and variables to 'drm_layout', as there's already
another DRAM type in the ast driver (AST_DDR2, AST_DDR3).

v2:
- avoid compiler warning with switch default (Dan)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://lore.kernel.org/r/20250826065032.344412-7-tzimmermann@suse.de

2 files changed, 19 insertions, 18 deletions

diff --git a/drivers/gpu/drm/ast/ast_2100.c b/drivers/gpu/drm/ast/ast_2100.c
index 44c33dd050eb..91541c8eaff7 100644
--- a/drivers/gpu/drm/ast/ast_2100.c
+++ b/drivers/gpu/drm/ast/ast_2100.c
@@ -35,10 +35,10 @@
  * DRAM type
  */
 
-static int ast_2100_get_dram_type_p2a(struct ast_device *ast)
+static enum ast_dram_layout ast_2100_get_dram_layout_p2a(struct ast_device *ast)
 {
 	u32 mcr_cfg;
-	int dram_type;
+	enum ast_dram_layout dram_layout;
 
 	ast_write32(ast, 0xf004, 0x1e6e0000);
 	ast_write32(ast, 0xf000, 0x1);
@@ -47,20 +47,21 @@ static int ast_2100_get_dram_type_p2a(struct ast_device *ast)
 	switch (mcr_cfg & 0x0c) {
 	case 0:
 	case 4:
-		dram_type = AST_DRAM_512Mx16;
+	default:
+		dram_layout = AST_DRAM_512Mx16;
 		break;
 	case 8:
 		if (mcr_cfg & 0x40)
-			dram_type = AST_DRAM_1Gx16;
+			dram_layout = AST_DRAM_1Gx16;
 		else
-			dram_type = AST_DRAM_512Mx32;
+			dram_layout = AST_DRAM_512Mx32;
 		break;
 	case 0xc:
-		dram_type = AST_DRAM_1Gx32;
+		dram_layout = AST_DRAM_1Gx32;
 		break;
 	}
 
-	return dram_type;
+	return dram_layout;
 }
 
 /*
@@ -298,9 +299,7 @@ static void ast_post_chip_2100(struct ast_device *ast)
 	u8 j;
 	u32 data, temp, i;
 	const struct ast_dramstruct *dram_reg_info;
-	int dram_type;
-
-	dram_type = ast_2100_get_dram_type_p2a(ast);
+	enum ast_dram_layout dram_layout  = ast_2100_get_dram_layout_p2a(ast);
 
 	j = ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xd0, 0xff);
 
@@ -327,7 +326,7 @@ static void ast_post_chip_2100(struct ast_device *ast)
 				for (i = 0; i < 15; i++)
 					udelay(dram_reg_info->data);
 			} else if (AST_DRAMSTRUCT_IS(dram_reg_info, DRAM_TYPE)) {
-				switch (dram_type) {
+				switch (dram_layout) {
 				case AST_DRAM_1Gx16:
 					data = 0x00000d89;
 					break;
diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 4c29ae9fb511..c15aef014f69 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -98,13 +98,15 @@ enum ast_config_mode {
 	ast_use_defaults
 };
 
-#define AST_DRAM_512Mx16 0
-#define AST_DRAM_1Gx16   1
-#define AST_DRAM_512Mx32 2
-#define AST_DRAM_1Gx32   3
-#define AST_DRAM_2Gx16   6
-#define AST_DRAM_4Gx16   7
-#define AST_DRAM_8Gx16   8
+enum ast_dram_layout {
+	AST_DRAM_512Mx16 = 0,
+	AST_DRAM_1Gx16 = 1,
+	AST_DRAM_512Mx32 = 2,
+	AST_DRAM_1Gx32 = 3,
+	AST_DRAM_2Gx16 = 6,
+	AST_DRAM_4Gx16 = 7,
+	AST_DRAM_8Gx16 = 8,
+};
 
 /*
  * Hardware cursor