9 Feb
2012
9 Feb
'12
7:51 p.m.
Hi Simon,
Thanks for looking at the patch.
On 9 February 2012 09:37, Simon Glass sjg@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
Regards, Shawn