[U-Boot] [PATCH] powerpc: change 86xx SMP boot method

[Becky Bruce]

On Nov 1, 2008, at 1:07 AM, Liu Dave wrote:

>> +/*
>> + * Copy the code for other cpus to execute into an
>> + * aligned location accessible via BPTR
>> + */
>> +void setup_mp(void)
>> +{
>> +	extern ulong __secondary_start_page;
>> +	ulong fixup = (ulong)&__secondary_start_page;
>> +	u32 bootpg;
>> +	u32 bootpg_va;
>> +
>> +	/*
>> +	 * If we have 4G or more of memory, put the boot page at 4Gb-1M.
>> +	 * Otherwise, put it at the very end of RAM.
>> +	 */
>> +	if (gd->ram_size > 0xfffff000)
>> +		bootpg = 0xfff00000;
>> +	else
>> +		bootpg = gd->ram_size - (1024 * 1024);
>> +
>> +	if (bootpg > CONFIG_SYS_MAX_DDR_BAT_SIZE) {
>> +		/* We're not covered by the DDR mapping, set up BAT  */
>> +		write_bat(DBAT7, CONFIG_SYS_SCRATCH_VA | BATU_BL_128K |
>> +			  BATU_VS | BATU_VP,
>> +			  bootpg | BATL_PP_RW | BATL_MEMCOHERENCE);
>> +		bootpg_va = CONFIG_SYS_SCRATCH_VA;
>> +	} else {
>> +		bootpg_va = bootpg;
>> +	}
>> +
>> +	memcpy((void *)bootpg_va, (void *)fixup, 4096);
>> +	flush_cache(bootpg_va, 4096);
>> +
>> +	/* remove the temporary BAT mapping */
>> +	if (bootpg >= CONFIG_SYS_MAX_DDR_BAT_SIZE)
>> +		write_bat(DBAT7, 0, 0);
>> +
>
>
> This condition should be >, not >=

No, it really should be >=.  The earlier condition is missing the  
"=".  I'll fix that.

>
>
>
>> diff --git a/cpu/mpc86xx/release.S b/cpu/mpc86xx/release.S
>> + */
>> +#if (CONFIG_NUM_CPUS > 1)
>> +	.align 12
>> +.globl __secondary_start_page
>> +__secondary_start_page:
>> +	.space 0x100	/* space over to reset vector loc */
>> +	mfspr	r0, MSSCR0
>> +	andi.	r0, r0, 0x0020
>> +	rlwinm	r0,r0,27,31,31
>> +	mtspr	PIR, r0
>> +
>> +	/* Invalidate BATs */
>> +	li	r0, 0
>> +	mtspr	IBAT0U, r0
>> +	mtspr	IBAT1U, r0
>> +	mtspr	IBAT2U, r0
>> +	mtspr	IBAT3U, r0
>> +	mtspr	IBAT4U, r0
>> +	mtspr	IBAT5U, r0
>> +	mtspr	IBAT6U, r0
>> +	mtspr	IBAT7U, r0
>> +	isync
>> +	mtspr	DBAT0U, r0
>> +	mtspr	DBAT1U, r0
>> +	mtspr	DBAT2U, r0
>> +	mtspr	DBAT3U, r0
>> +	mtspr	DBAT4U, r0
>> +	mtspr	DBAT5U, r0
>> +	mtspr	DBAT6U, r0
>> +	mtspr	DBAT7U, r0
>> +	isync
>> +	sync
>
>
> I think it is not neccessary, because the MMU is not turned on in
> u-boot.
> However, kernel should have correct invalidate BAT before MMU on.

This is here because it exists in the current SMP secondary boot code,  
and I tried to change it as little as possible in this patch.  For all  
I know, there's some stupid homebrew customer OS that depends on this.

>
>
>> diff --git a/include/configs/MPC8610HPCD.h
>> b/include/configs/MPC8610HPCD.h
>> index 67b2764..75aa911 100644
>> --- a/include/configs/MPC8610HPCD.h
>> +++ b/include/configs/MPC8610HPCD.h
>> @@ -36,6 +36,12 @@
>>
>> #define CONFIG_SYS_RESET_ADDRESS	0xfff00100
>>
>> +/*
>> + * virtual address to be used for temporary mappings.  There
>> + * should be 128k free at this VA.
>> + */
>> +#define CONFIG_SYS_SCRATCH_VA	0xc0000000
>> +
>> #define CONFIG_PCI		1	/* Enable PCI/PCIE*/
>> #define CONFIG_PCI1		1	/* PCI controler 1 */
>> #define CONFIG_PCIE1		1	/* PCIe 1 connected to
>> ULI bridge */
>> @@ -92,6 +98,7 @@
>>
>> #define CONFIG_SYS_DDR_SDRAM_BASE	0x00000000	/* DDR
>> is system memory*/
>> #define CONFIG_SYS_SDRAM_BASE		
>> CONFIG_SYS_DDR_SDRAM_BASE
>> +#define CONFIG_SYS_MAX_DDR_BAT_SIZE	0x80000000	/* BAT
>> mapping size */
>> #define CONFIG_VERY_BIG_RAM
>
>
> I believe the 8610 processor doesn't support MP.
> :)

It doesn't.  These defines are here for completeness - they're  
generally useful.  I can pull them out of they're really bothering  
people.

>
>
> Thanks,
> Dave

Thanks for reviewing!
-Becky