From 4327a6137ed43a091d900b1ac833345d60f32228 Mon Sep 17 00:00:00 2001
From: Jammy Huang <jammy_huang@aspeedtech.com>
Date: Fri, 21 Apr 2023 08:33:54 +0800
Subject: [PATCH] drm/ast: Fix ARM compatibility
Git-commit: 4327a6137ed43a091d900b1ac833345d60f32228
Patch-mainline: v6.4-rc2
References: git-fixes
ARM architecture only has 'memory', so all devices are accessed by
MMIO if possible.
Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230421003354.27767-1-jammy_huang@aspeedtech.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/ast/ast_main.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index f83ce77127cb..a6d0ee4da2b8 100644
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -425,11 +425,12 @@ struct ast_private *ast_device_create(const struct drm_driver *drv,
return ERR_PTR(-EIO);
/*
- * If we don't have IO space at all, use MMIO now and
- * assume the chip has MMIO enabled by default (rev 0x20
- * and higher).
+ * After AST2500, MMIO is enabled by default, and it should be adopted
+ * to be compatible with Arm.
*/
- if (!(pci_resource_flags(pdev, 2) & IORESOURCE_IO)) {
+ if (pdev->revision >= 0x40) {
+ ast->ioregs = ast->regs + AST_IO_MM_OFFSET;
+ } else if (!(pci_resource_flags(pdev, 2) & IORESOURCE_IO)) {
drm_info(dev, "platform has no IO space, trying MMIO\n");
ast->ioregs = ast->regs + AST_IO_MM_OFFSET;
}
--
2.35.3