Hi Martijn,
On Monday 15 September 2008, Martijn de Gouw wrote:
+#ifdef CFG_SDR_CONFIG mov r1, #CFG_SDR_CONFIG
- mov r9, #0xff
+#else
- mov r1, #0x1d /* 256 MB, two banks of 128 MB */
- mov r9, #0
+#endif
I don't want such $ifdef's in global code. Why do you thinkthat 2 x 128 MB would be a default configuration for all IXP based boards?
When CFG_SDR_CONFIG is defined, it holds the memory size, which is set in the config.h When this value is not set, autodetection is assumed. Setting up the board as 2 x 128Mb is used for the autodetection.
Understood. Nevertheless the resulting code is quite complex hard to read.
+sdr_init:
/* snip */
+sdr_init_done:
This whole test makes not much sense to me. I think the code should be changed to use the standard get_ram_size() funciton instead (see common/memsize.c).
get_ram_size will nog set the memory controller to the correct size. The ixp can not run C code when memory is not initialized.
Because of the missing C environment (stack etc)? We could probably use a part of the QueueManager SRAM for a temorary initial stack, so that we could run C code very early. And do the SDRAM initialization and autodetection in C instead of assembler (as done for PPC).
If we could run this SDRAM setup code in C, you could implement a weak default init function that could be overwritten by a board specific version (in your case). This way we wouldn't add more custom stuff into the common/generic source files.
What do you think?
Maybe it could be used as a replacement for the code in pdnb.c yes.
Yes. This should be replaced.
Best regards, Stefan
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