[PATCH 6.12 399/567] fbdev: gbefb: fix to use physical address instead of dma address

Greg Kroah-Hartman
2026-01-06T17:36:15Z

From: Rene Rebe <rene@exactco.de>

commit e3f44742bbb10537fe53d83d20dea2a7c167674d upstream.

While debuggigng why X would not start on mips64 Sgi/O2 I found the
phys adress being off. Turns out the gbefb passed the internal
dma_addr as phys. May be broken pre git history. Fix by converting
dma_to_phys.

Signed-off-by: René Rebe <rene@exactco.de>
Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/video/fbdev/gbefb.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/video/fbdev/gbefb.c
+++ b/drivers/video/fbdev/gbefb.c
@@ -12,6 +12,7 @@
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/fb.h>
@@ -65,7 +66,7 @@ struct gbefb_par {
static unsigned int gbe_mem_size = CONFIG_FB_GBE_MEM * 1024*1024;
static void *gbe_mem;
static dma_addr_t gbe_dma_addr;
-static unsigned long gbe_mem_phys;
+static phys_addr_t gbe_mem_phys;

static struct {
uint16_t *cpu;
@@ -1183,7 +1184,7 @@ static int gbefb_probe(struct platform_d
goto out_release_mem_region;
}

- gbe_mem_phys = (unsigned long) gbe_dma_addr;
+ gbe_mem_phys = dma_to_phys(&p_dev->dev, gbe_dma_addr);
}

par = info->par;