drm/ast: Store CRTC memory request threshold in device quirks

Store each hardware's CRTC memory threshold in the specific instance
of struct ast_device_quirks. Removes the calls to IS_AST_GENn() from
ast_set_crtthd_reg().

The values stored in the registers appear to be plain limits. Hence
write them in the driver in decimal format instead of hexadecimal.

Signed-off-by: Thomas Zimmermann <[e-mail]>
Reviewed-by: Jocelyn Falempe <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/gpu/drm/ast/ast_2000.c

···
 }
 
 static const struct ast_device_quirks ast_2000_device_quirks = {
+	.crtc_mem_req_threshold_low = 31,
+	.crtc_mem_req_threshold_high = 47,
 };
 
 struct drm_device *ast_2000_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2100.c

···
 }
 
 static const struct ast_device_quirks ast_2100_device_quirks = {
+	.crtc_mem_req_threshold_low = 47,
+	.crtc_mem_req_threshold_high = 63,
 };
 
 struct drm_device *ast_2100_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2200.c

···
 }
 
 static const struct ast_device_quirks ast_2200_device_quirks = {
+	.crtc_mem_req_threshold_low = 47,
+	.crtc_mem_req_threshold_high = 63,
 };
 
 struct drm_device *ast_2200_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2300.c

···
 }
 
 static const struct ast_device_quirks ast_2300_device_quirks = {
+	.crtc_mem_req_threshold_low = 96,
+	.crtc_mem_req_threshold_high = 120,
 };
 
 struct drm_device *ast_2300_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2400.c

···
 }
 
 static const struct ast_device_quirks ast_2400_device_quirks = {
+	.crtc_mem_req_threshold_low = 96,
+	.crtc_mem_req_threshold_high = 120,
 };
 
 struct drm_device *ast_2400_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2500.c

···
 }
 
 static const struct ast_device_quirks ast_2500_device_quirks = {
+	.crtc_mem_req_threshold_low = 96,
+	.crtc_mem_req_threshold_high = 120,
 };
 
 struct drm_device *ast_2500_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_2600.c

···
 }
 
 static const struct ast_device_quirks ast_2600_device_quirks = {
+	.crtc_mem_req_threshold_low = 160,
+	.crtc_mem_req_threshold_high = 224,
 };
 
 struct drm_device *ast_2600_device_create(struct pci_dev *pdev,

drivers/gpu/drm/ast/ast_drv.h

···
  */
 
 struct ast_device_quirks {
+	/*
+	 * CRTC memory request threshold
+	 */
+	unsigned char crtc_mem_req_threshold_low;
+	unsigned char crtc_mem_req_threshold_high;
 };
 
 struct ast_device {

drivers/gpu/drm/ast/ast_mode.c

···
 
 static void ast_set_crtthd_reg(struct ast_device *ast)
 {
-	/* Set Threshold */
-	if (IS_AST_GEN7(ast)) {
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa7, 0xe0);
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa6, 0xa0);
-	} else if (IS_AST_GEN6(ast) || IS_AST_GEN5(ast) || IS_AST_GEN4(ast)) {
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa7, 0x78);
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa6, 0x60);
-	} else if (IS_AST_GEN3(ast) || IS_AST_GEN2(ast)) {
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa7, 0x3f);
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa6, 0x2f);
-	} else {
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa7, 0x2f);
-		ast_set_index_reg(ast, AST_IO_VGACRI, 0xa6, 0x1f);
-	}
+	u8 vgacra6 = ast->quirks->crtc_mem_req_threshold_low;
+	u8 vgacra7 = ast->quirks->crtc_mem_req_threshold_high;
+
+	ast_set_index_reg(ast, AST_IO_VGACRI, 0xa7, vgacra7);
+	ast_set_index_reg(ast, AST_IO_VGACRI, 0xa6, vgacra6);
 }
 
 static void ast_set_sync_reg(struct ast_device *ast,