Hi Shawn, On Thu, Feb 9, 2012 at 10:51 AM, Shawn Guo <shawn....@linaro.org> wrote: > Hi Simon, > > Thanks for looking at the patch. > > On 9 February 2012 09:37, Simon Glass <s...@chromium.org> wrote: > ... >>> fdt_high - if set this restricts the maximum address that the >>> flattened device tree will be copied into upon boot. >>> + For example, if you have a system with 1 GB memory >>> + at physical address 0x10000000, while Linux kernel >>> + only recognizes the first 704 MB as low memory, you >>> + may need to set fdt_high as 0x3C000000 to have the >>> + device tree blob be copied to the maximum address >>> + of the 704 MB low memory, so that Linux kernel can >>> + access it during the boot procedure. >> >> I don't entirely understand that - 0x3c000000 is at a 768MB offset >> into kernel space think - where does the 64MB difference come from? >> Perhaps explain that a bit more. >> > All the numbers above come from the real case of Freescale i.MX6Q > Sabrelite board: > > 0x2C000000 (704 MB) + 0x10000000 (physical base) = 0x3C000000
OK I see, thanks. Regards, Simon > > Regards, > Shawn _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
