From dc3ae06c5f2170d879ff58696f629d8c3868aec3 Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel@sholland.org>
Date: Sun, 24 Apr 2022 11:26:21 -0500
Subject: drm/sun4i: Remove obsolete references to PHYS_OFFSET
Git-commit: dc3ae06c5f2170d879ff58696f629d8c3868aec3
Patch-mainline: v5.18-rc5
References: bsc#1190786

commit b4bdc4fbf8d0 ("soc: sunxi: Deal with the MBUS DMA offsets in a
central place") added a platform device notifier that sets the DMA
offset for all of the display engine frontend and backend devices.

The code applying the offset to DMA buffer physical addresses was then
removed from the backend driver in commit 756668ba682e ("drm/sun4i:
backend: Remove the MBUS quirks"), but the code subtracting PHYS_OFFSET
was left in the frontend driver.

As a result, the offset was applied twice in the frontend driver. This
likely went unnoticed because it only affects specific configurations
(scaling or certain pixel formats) where the frontend is used, on boards
with both one of these older SoCs and more than 1 GB of DRAM.

In addition, the references to PHYS_OFFSET prevent compiling the driver
on architectures where PHYS_OFFSET is not defined.

Fixes: b4bdc4fbf8d0 ("soc: sunxi: Deal with the MBUS DMA offsets in a central place")
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220424162633.12369-4-samuel@sholland.org
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/sun4i/sun4i_frontend.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_frontend.c b/drivers/gpu/drm/sun4i/sun4i_frontend.c
index 56ae38389db0b..462fae73eae98 100644
--- a/drivers/gpu/drm/sun4i/sun4i_frontend.c
+++ b/drivers/gpu/drm/sun4i/sun4i_frontend.c
@@ -222,13 +222,11 @@ void sun4i_frontend_update_buffer(struct sun4i_frontend *frontend,
 
 	/* Set the physical address of the buffer in memory */
 	paddr = drm_fb_cma_get_gem_addr(fb, state, 0);
-	paddr -= PHYS_OFFSET;
 	DRM_DEBUG_DRIVER("Setting buffer #0 address to %pad\n", &paddr);
 	regmap_write(frontend->regs, SUN4I_FRONTEND_BUF_ADDR0_REG, paddr);
 
 	if (fb->format->num_planes > 1) {
 		paddr = drm_fb_cma_get_gem_addr(fb, state, swap ? 2 : 1);
-		paddr -= PHYS_OFFSET;
 		DRM_DEBUG_DRIVER("Setting buffer #1 address to %pad\n", &paddr);
 		regmap_write(frontend->regs, SUN4I_FRONTEND_BUF_ADDR1_REG,
 			     paddr);
@@ -236,7 +234,6 @@ void sun4i_frontend_update_buffer(struct sun4i_frontend *frontend,
 
 	if (fb->format->num_planes > 2) {
 		paddr = drm_fb_cma_get_gem_addr(fb, state, swap ? 1 : 2);
-		paddr -= PHYS_OFFSET;
 		DRM_DEBUG_DRIVER("Setting buffer #2 address to %pad\n", &paddr);
 		regmap_write(frontend->regs, SUN4I_FRONTEND_BUF_ADDR2_REG,
 			     paddr);
-- 
2.36.0