On Wed, 2015-08-05 at 17:17 +0200, Hans de Goede wrote:
>  >    > sunxi_display.fb_size =
>  >    >       > (mode->xres * mode->yres * 4 + 0xfff) & ~0xfff;
> +>    > overscan_offset = (overscan_y * mode->xres + overscan_x) * 4;
> +>    > /* We want to keep the fb_base for simplefb page aligned, where as
> +>    >  * the sunxi dma engines will happily accept an unaligned address. */
> +>    > if (overscan_offset)
> +>    >       > sunxi_display.fb_size += 0x1000;
Why plus 4K regardless of the magnitude of overscan_offset? What if it was
0x1004?

Also, what's the link between fb_base's alignment and fb_size which is
implied by the comment?

>  >    > gd->fb_base = gd->bd->bi_dram[0].start +
>  >    >       >       gd->bd->bi_dram[0].size - sunxi_display.fb_size;
>  >    > sunxi_engines_init();
> ->    > sunxi_mode_set(mode, gd->fb_base - CONFIG_SYS_SDRAM_BASE);
> +
> +>    > fb_dma_addr = gd->fb_base - CONFIG_SYS_SDRAM_BASE;
> +>    > sunxi_display.fb_addr = gd->fb_base;
> +>    > if (overscan_offset) {
> +>    >       > fb_dma_addr += 0x1000 - (overscan_offset & 0xfff);
> +>    >       > sunxi_display.fb_addr += (overscan_offset + 0xfff) & ~0xfff;
> +>    >       > memset((void *)gd->fb_base, 0, sunxi_display.fb_size);
> +>    >       > flush_cache(gd->fb_base, sunxi_display.fb_size);
> +>    > }

Hrm, I think this starts to answer, but I'm still not sure I follow, sorry.

> +     sunxi_mode_set(mode, fb_dma_addr);
>  
>       /*
>  >    >  * These are the only members of this structure that are used. All the
>  >    >  * others are driver specific. There is nothing to decribe pitch or


Pre-existing typo "describe".

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