[PATCH 1/3] 8xx: Analogue & Micro Adder875 board support.
scottwood at freescale.com
Tue Jan 15 02:28:59 EST 2008
On Sun, Jan 13, 2008 at 02:26:12PM +0000, Bryan O'Donoghue wrote:
> I've applied your code against Linus' git v2.6.26-rc7 as at today.
> I have to apply
It should apply against paulus's tree.
> make adder87x-uboot_defconfig
> make uImage
make zImage, not uImage.
> cp arch/powerpc/boot/uImage /tftpboot - which is my tftpd root
Use cuImage.8xx, not uImage.
> In U-Boot then.
> => tftpboot 0x400000 uImage
> => bootm 0x400000
0x400000 is where u-boot is going to want to relocate the image to, so
loading the uImage there may not work.
> Which doesn't boot.
> Attaching a BDI2000 to the target board I see that the kernel is
> panicing somewhere around line 104 of arch/powerpc/kernel/prom.c in
> of_scan_flat_dt - presumably because the kernel cannot find an
> OpenFirmware tree..
Yes, a uImage target will be expecting to be handed a device tree. The
cuImage target has a device tree embedded and accepts the old-style bd_t.
> I admit not understanding everything I should about where the output
> of .dts & dtc "go" with respect to booting Linux.... but, didn't want to
> ask on the list - lest I display a "lack of knowledge" ...
Nothing wrong with asking... doing so on the list just means a larger
pool of people to respond, and that others with the same question can see
> /* pass open firmware flat tree */
> #define CONFIG_OF_LIBFDT 1
> #undef CONFIG_OF_FLAT_TREE
> #define CONFIG_OF_BOARD_SETUP 1
> #define CONFIG_OF_HAS_BD_T 1
> #define CONFIG_OF_HAS_UBOOT_ENV 1
> #define OF_CPU "PowerPC,875 at 0"
> #define OF_SOC "soc875 at ff000000"
> #define OF_TBCLK (bd->bi_busfreq / 4)
You'll probably need some 8xx-specific code if you want to go this route.
You'd also need to change the bootm command line to the three-argument
version, with the third argument being the address of the device tree
blob (the second argument can be - if there's no initrd).
If you're not comfortable with the device tree stuff, I recommend just
using cuImage for now.
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