[U-Boot-Users] the question about the Flat Device Tree on MPC8360?

[Jerry Van Baren]

Jerry Van Baren wrote:
> ?? wrote:
>> HI, friends.
>>
>>   I want to update my linux version from 2.6.11 to 2.6.22 on MPC8360 board, I
>> always fail when the linux version is about 2.6.11. Someone told me that I need to
>> build the Flat Device Tree. I see that the U-boot-1.2.0 has one FDT command, but I
>> did not know how to use this command and how to use the Flat Device Tree.
>>   I once see a document from freescale that the FDT file need tftp download to DDR
>> memory first then bootm the linux. What's that FDT file? how can i get it? which
>> DDR address that I need to tftp download? 
>>   What is the FDT? Could someone teach me? Thanks.
> 
> Hi ??,
> 
> u-boot 1.2.0's support of FDT is crude.  Upgrade to the tip o' the tree 
> (1.3.2rc3), or at least to 1.3.1.
> 
> The flattened device tree (FDT) is a method of passing hardware 
> configuration information to the kernel.  It is described in the kernel 
> documentation directory/file:
>    ./Documentation/powerpc/booting-without-of.txt
> 
> You need a recent kernel, 2.6.22 probably is OK.  I'm running 2.6.25rc3 
> (tip 'o the tree as of a week or so ago).
> 
> I have a mpc8360emds eval board, so I configure the kernel:
>    $ make mpc836x_mds_defconfig
> and build it
>    $ make

I forgot to mention, with the tip 'o the kernel tree and the ELDK 4.1 
(4.2rc), the kernel compile breaks on an unrecognized register due to 
CONFIG_FSL_EMB_PERFMON.  I have not succeeded in chasing down the cause 
yet, so I simply commented it out:

diff --git a/arch/powerpc/kernel/pmc.c b/arch/powerpc/kernel/pmc.c
index 0516e2d..e26e63a 100644
--- a/arch/powerpc/kernel/pmc.c
+++ b/arch/powerpc/kernel/pmc.c
@@ -26,7 +26,7 @@

  static void dummy_perf(struct pt_regs *regs)
  {
-#if defined(CONFIG_FSL_EMB_PERFMON)
+#if 0 //gvb// defined(CONFIG_FSL_EMB_PERFMON)
         mtpmr(PMRN_PMGC0, mfpmr(PMRN_PMGC0) & ~PMGC0_PMIE);
  #elif defined(CONFIG_PPC64) || defined(CONFIG_6xx)
  	if (cur_cpu_spec->pmc_type == PPC_PMC_IBM)

Best regards,
gvb