Re: [PATCH 3/3] fbdev: sh_mobile_lcdc: use dma_mmap_coherent if available
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Date: 2012-07-25 11:10:42
Also in:
linux-arm-kernel, linux-media, lkml
Hi Eiraku-san, Thank you for the patch. On Wednesday 25 July 2012 15:29:24 Hideki EIRAKU wrote:
fb_mmap() implemented in fbmem.c uses smem_start as the physical address of the frame buffer. In the sh_mobile_lcdc driver, the smem_start is a dma_addr_t that is not a physical address when IOMMU is enabled. dma_mmap_coherent() maps the address correctly. It is available on ARM platforms.
This looks good to me, but will need to be rebased on top of the sh_mobile_lcdc patches currently queued for v3.6. You can find them in the fbdev-next branch of git://github.com/schandinat/linux-2.6.git. In particular, these patches add support for overlays exported through additional fbdev devices. You will need to initialize .fb_mmap in both sh_mobile_lcdc_overlay_ops and sh_mobile_lcdc_ops.
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Signed-off-by: Hideki EIRAKU <redacted> --- drivers/video/sh_mobile_lcdcfb.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-)diff --git a/drivers/video/sh_mobile_lcdcfb.cb/drivers/video/sh_mobile_lcdcfb.c index e672698..65732c4 100644--- a/drivers/video/sh_mobile_lcdcfb.c +++ b/drivers/video/sh_mobile_lcdcfb.c@@ -1393,6 +1393,17 @@ static int sh_mobile_lcdc_blank(int blank, structfb_info *info) return 0; } +#ifdef ARCH_HAS_DMA_MMAP_COHERENT +static int +sh_mobile_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) +{ + struct sh_mobile_lcdc_chan *ch = info->par; + + return dma_mmap_coherent(ch->lcdc->dev, vma, ch->fb_mem, + ch->dma_handle, ch->fb_size); +} +#endif + static struct fb_ops sh_mobile_lcdc_ops = { .owner = THIS_MODULE, .fb_setcolreg = sh_mobile_lcdc_setcolreg,@@ -1408,6 +1419,9 @@ static struct fb_ops sh_mobile_lcdc_ops = { .fb_release = sh_mobile_release, .fb_check_var = sh_mobile_check_var, .fb_set_par = sh_mobile_set_par, +#ifdef ARCH_HAS_DMA_MMAP_COHERENT + .fb_mmap = sh_mobile_fb_mmap, +#endif }; static void
-- Regards, Laurent Pinchart