On Friday 31 May 2013 16:22:24 Michal Simek wrote:
> if (pdata->fb_phys) {
> drvdata->fb_phys = pdata->fb_phys;
> - drvdata->fb_virt = ioremap(pdata->fb_phys, fbsize);
> + drvdata->fb_virt_io = ioremap(pdata->fb_phys, fbsize);
> +
> + if (!drvdata->fb_virt_io) {
> + dev_err(dev, "Could not allocate frame buffer
> memory\n");
> + rc = -ENOMEM;
> + if (drvdata->flags & BUS_ACCESS_FLAG)
> + goto err_fbmem;
> + else
> + goto err_region;
> + }
> +
> + /* Clear (turn to black) the framebuffer */
> + memset_io(drvdata->fb_virt_io, 0, fbsize);
> } else {
> - drvdata->fb_alloced = 1;
> drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(fbsize),
> &drvdata->fb_phys, GFP_KERNEL);
> - }
>
I think you also want to use ioremap_wc or dma_alloc_writecombine
here, to get a write-combining mapping, rather than a device mapping
that you would use for MMIO register access.
There is also a builtin assumption in the code above that the DMA
address space pointer (which you pass into REG_FB_ADDR) is the
same as what you pass into drvdata->info.fix.smem_start. That is
not the case in general, but I don't see a good way around it
when pdata->fb_phys is set by the platform to something outside
of system memory. It should probably have a comment next to it.
Arnd
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