[U-Boot] Galileo instructions

[Simon Glass]

Hi Bin,

On 14 September 2015 at 06:49, Bin Meng <bmeng.cn at gmail.com> wrote:
>
> Hi Simon,
>
> On Mon, Sep 14, 2015 at 8:45 PM, Simon Glass <sjg at chromium.org> wrote:
> > Hi Bin,
> >
> > On 13 September 2015 at 03:28, Bin Meng <bmeng.cn at gmail.com> wrote:
> >> Hi Simon,
> >>
> >> On Sun, Sep 13, 2015 at 5:06 AM, Simon Glass <sjg at chromium.org> wrote:
> >>> Hi Bin,
> >>>
> >>> I have a Galileo Gen 2 and am trying to get U-Boot to start on it. The
> >>> first problem I have is that the schematic says the chip is a W25Q64FV
> >>> which I think is an 8MB part, but the image produced is only 1MB.
> >>
> >> Yes, the board has an 8MB SPI flash, but U-Boot (u-boot.rom) only
> >> utilizes the last 1MB.
> >>
> >>>
> >>> Also I know that there is a Gen 1 and a Gen 2. I recall you saying
> >>> that U-Boot supports the Gen 2 but can easily support the Gen 1. But
> >>> perhaps I have done something wrong.
> >>>
> >>
> >> I've verified U-Boot can boot on both gen1 and gen2 boards.
> >
> > Thanks.
> >>
> >>> I downloaded the BSP from here:
> >>>
> >>> https://downloadcenter.intel.com/download/23197/Intel-Quark-BSP
> >>>
> >>> File name: Board_Support_Package_Sources_for_Intel_Quark_v1.1.0.7z
> >>> Version: 1.1.0 (Latest)
> >>>
> >>> Date: 03/03/2015
> >>> Size: 2.72 MB
> >>>
> >>> Any hints? I am using a dediprog em100 with a test clip over the flash chip.
> >>>
> >>
> >> It's not clear to me what issue you got. It looks like there might be
> >> some issue for dediporg em100 to handle the rom size mismatch? If this
> >> is the case, you can just create an 8MB u-boot.rom with the 1MB
> >> version with other 7MB filled up with 0xFFs.
> >
> > OK I did this and it works, thanks.
>
> So it's indeed the dediprog em100 cannot handle the rom mismatch?
>
> > Why don't we just change the ROM size? This point is not mentioned in README.x86.
> >
>
> 1MB is enough for U-Boot. u-boot.rom does not necessarily have to
> match the SPI flash size. And on Galileo since there is no Intel ME,
> so we don't need to create a whole 8MB rom. This is the same as Intel
> CrownBay, which has a 2MB SPI flash, but still 1MB u-boot.rom.

What is the benefit of this mismatch? I only see the down-side at
present (user confusion, unbootable .rom).

Regards,
Simon