DMA_TO_DEVICE synchronisation must be done after the last modification
of the memory region by the software and before it is handed off to
the device.
Signed-off-by: Hui Tang <tanghu...@huawei.com>
---
drivers/video/fbdev/grvga.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/video/fbdev/grvga.c b/drivers/video/fbdev/grvga.c
index 24818b2..25ae9ef 100644
--- a/drivers/video/fbdev/grvga.c
+++ b/drivers/video/fbdev/grvga.c
@@ -435,6 +435,8 @@ static int grvga_probe(struct platform_device *dev)
retval = -ENOMEM;
goto dealloc_cmap;
}
+
+ memset((unsigned long *) virtual_start, 0, grvga_mem_size);
} else { /* Allocate frambuffer memory */
unsigned long page;
@@ -449,6 +451,7 @@ static int grvga_probe(struct platform_device *dev)
goto dealloc_cmap;
}
+ memset((unsigned long *) virtual_start, 0, grvga_mem_size);
physical_start = dma_map_single(&dev->dev, (void
*)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
/* Set page reserved so that mmap will work. This is necessary
@@ -463,8 +466,6 @@ static int grvga_probe(struct platform_device *dev)
par->fb_alloced = 1;
}
- memset((unsigned long *) virtual_start, 0, grvga_mem_size);
-
info->screen_base = (char __iomem *) virtual_start;
info->fix.smem_start = physical_start;
info->fix.smem_len = grvga_mem_size;
--
2.8.1
