[yocto] [meta-raspberrypi][PATCH v3] u-boot: Simplify boot script
net147 at gmail.com
Wed Nov 9 17:57:02 PST 2016
On 6 November 2016 at 22:57, Paul Barker <paul at paulbarker.me.uk> wrote:
> On Sat, 5 Nov 2016 12:50:07 +1100
> Jonathan Liu <net147 at gmail.com> wrote:
>> A patch is added to check if the firmware loaded a device tree blob
>> into memory and set the fdt_addr_r variable if it is found. The U-Boot
>> script will then read the command line arguments generated by the
>> firmware from the device tree and boot the kernel with the command
>> line arguments and the loaded device tree.
>> This allows things like MAC address, board revision and serial number
>> to be correctly configured and options in config.txt to be used.
>> Signed-off-by: Jonathan Liu <net147 at gmail.com>
>> Changes in v3:
>> - Removed incorrect check if fdt_addr_r is already set. The check
>> condition was inverted and fdt_addr_r variable is always set to
>> 0x100 by default.
>> Changes in v2:
>> - Instead of setting device_tree_address to 0x100 in config.txt, patch
>> U-Boot to detect the device tree blob address if it was loaded.
> I'm still getting the same "Could not find a valid device tree" failure
> on the model B+.
> I've tried running vcdbg but got the following error from the kernel
> vc_mem_mmap: length 4096 is too big
> vcdbg itself then said:
> debug_sym: AccessVideoCoreMemory: mmap failed: Invalid argument(22)
> debug_sym: OpenVideoCoreMemoryFileWithOffset: ReadVideoCoreMemory @VC_SYMBOL_BASE_OFFSET (0x00002800) failed
> Unable to open videocore memory access: -5
> This was after adding "dtdebug=on" to config.txt
> Not sure where to go next with this. I might need to go off on a Yak
> shaving mission and find out why the mmap is failing.
A patch is being worked on upstream - https://patchwork.ozlabs.org/patch/692412/
I think we will wait until it is accepted upstream and then backport it.
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