[PATCH] ARM: bootm: take into account gd->ram_top

[Patrice CHOTARD]

Hi Baruch

On 8/17/20 6:46 AM, Baruch Siach wrote:
> Hi Patrick, all,
>
> On Thu, Feb 13 2020, Patrick Delaunay wrote:
>> From: Patrice Chotard <patrice.chotard at st.com>
>>
>> If gd->ram_top has been tuned using board_get_usable_ram_top(),
>> it must be taken into account when reserving arch lmb.
>>
>> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
>> Reviewed-by: Patrick DELAUNAY <patrick.delaunay at st.com>
>> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> [snip]
>> diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
>> index a135bcfc7b..f4b5ca6de0 100644
>> --- a/arch/arm/lib/bootm.c
>> +++ b/arch/arm/lib/bootm.c
>> @@ -75,6 +75,9 @@ void arch_lmb_reserve(struct lmb *lmb)
>>  			gd->bd->bi_dram[bank].size - 1;
>>  		if (sp > bank_end)
>>  			continue;
>> +		if (bank_end > gd->ram_top)
>> +			bank_end = gd->ram_top - 1;
>> +
> This patch (now committed as 8ce1f10cf2b1) breaks kernel boot on Armada
> 8040 based Clearfog GT-8K with 16GB RAM. See below the console output of
> v2020.10-rc2 with a few added prints.
>
> The first memory bank (bi_dram[0]) goes from 0 to 3GB. The rest
> (4GB-17GB) is on bi_dram[1] (see a8k_dram_init_banksize()). ram_top is
> set to 2GB on
> arch/arm/mach-mvebu/arm64-common.c:board_get_usable_ram_top().

If i have correctly understood, before this patch, on your platform U-boot was using a memory area over

the ram_top limit set to 2Gb ? which is not correct.

You probably have to rework the platform memory mapping in order to either

_ make all needed memory area fit inside the ram_top limit (2Gb)

or

_ increase the ram_top limit over 2Gb.

It's only assumption as i don't know your platform.

Patrice


>
> Reverting commit 8ce1f10cf2b1 on top of v2020.10-rc2 fixes boot.
>
> Any Idea?
>
> Found /extlinux/extlinux.conf
> Retrieving file: /extlinux/extlinux.conf
> ## Current stack ends at 0x7fb24300
> arch_lmb_reserve: bank_end: bfffffff ram_top: 80000000
> 62 bytes read in 21 ms (2 KiB/s)
> 1:	linux
> Retrieving file: /extlinux/Image
> ## Current stack ends at 0x7fb23960
> arch_lmb_reserve: bank_end: bfffffff ram_top: 80000000
> 13740544 bytes read in 1266 ms (10.4 MiB/s)
> Retrieving file: /extlinux/armada-8040-clearfog-gt-8k.dtb
> ## Current stack ends at 0x7fb23960
> arch_lmb_reserve: bank_end: bfffffff ram_top: 80000000
> 33368 bytes read in 31 ms (1 MiB/s)
> ## Current stack ends at 0x7fb23cd0
> arch_lmb_reserve: bank_end: bfffffff ram_top: 80000000
> ## Flattened Device Tree blob at 04f00000
>    Booting using the fdt blob at 0x4f00000
>    Loading Device Tree to 00000000bfff4000, end 00000000bffff257 ... "Synchronous Abort" handler, esr 0x96000045
> elr: 000000000006e1cc lr : 0000000000068fd8 (reloc)
> elr: 000000007ffa91cc lr : 000000007ffa3fd8
> x0 : ffffffffffffffff x1 : 00000000bfffc258
> x2 : 0000000000000000 x3 : ffffffffffff7da7
> x4 : 0000000004f08258 x5 : 00000000bfff4000
> x6 : 00000000bfff4000 x7 : 000000000000000f
> x8 : 000000007fb23bf8 x9 : 0000000000000008
> x10: 00000000bffff257 x11: 00000000bffff257
> x12: 0000000000000000 x13: fffffffffffff000
> x14: 00000000bfff4000 x15: 0000000000000021
> x16: 000000007ff7bc38 x17: 0000000000000000
> x18: 000000007fb2add0 x19: 00000000bfff4000
> x20: 0000000004f00000 x21: 000000000000b258
> x22: 0000000058820000 x23: 0000000000000010
> x24: 000000007ffe3c40 x25: 000000007fb23cb8
> x26: 00000000c0000000 x27: 0000000000000000
> x28: 000000007fc3fd50 x29: 000000007fb23bd0
>
> Code: 54000061 aa0603e0 d65f03c0 38606882 (38206822) 
> Resetting CPU ...
>
> Thanks,
> baruch
>
>>  		lmb_reserve(lmb, sp, bank_end - sp + 1);
>>  		break;
>>  	}