[PATCH 2/2] rockchip: sdram: Fix reserve of 2 MiB at start of DRAM

[Jonas Karlman]

Hi Kever,

On 2025-01-24 12:17, Kever Yang wrote:
> Hi Jonas,
> 
>      This patch has the same main change with Heiko's patch.
> 
> https://patchwork.ozlabs.org/project/uboot/patch/20241121142731.1202209-9-heiko@sntech.de/
> 

Ohh, I have completely missed that patch when testing the RK3576 series.
Not sure how, sorry for extra noise and please ignore my patch :-)

Regards,
Jonas

> 
> Thanks,
> - Kever
> On 2025/1/24 06:02, Jonas Karlman wrote:
>> Normally 2 MiB at the beginning of DRAM is reserved for TF-A use.
>> However, this only works as intended when DRAM starts at 0x0.
>>
>> When DRAM starts at e.g. 0x40000000 this reservation never happens, and
>> U-Boot or Linux may try to read/write into secure memory.
>>
>> Fix this by taking CFG_SYS_SDRAM_BASE into consideration when reserving
>> 2 MiB at start of DRAM.
>>
>> Also change to use SZ_2M and SZ_32M for consistency.
>>
>> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
>> ---
>>   arch/arm/mach-rockchip/sdram.c | 12 ++++++------
>>   1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm/mach-rockchip/sdram.c b/arch/arm/mach-rockchip/sdram.c
>> index 3d3fc327234f..caca6f917305 100644
>> --- a/arch/arm/mach-rockchip/sdram.c
>> +++ b/arch/arm/mach-rockchip/sdram.c
>> @@ -182,9 +182,9 @@ static int rockchip_dram_init_banksize(void)
>>   		 * BL31 (TF-A) reserves the first 2MB but DDR_MEM tag may not
>>   		 * have it, so force this space as reserved.
>>   		 */
>> -		if (start_addr < SZ_2M) {
>> -			size -= SZ_2M - start_addr;
>> -			start_addr = SZ_2M;
>> +		if (start_addr < CFG_SYS_SDRAM_BASE + SZ_2M) {
>> +			size -= CFG_SYS_SDRAM_BASE + SZ_2M - start_addr;
>> +			start_addr = CFG_SYS_SDRAM_BASE + SZ_2M;
>>   		}
>>   
>>   		/*
>> @@ -302,8 +302,8 @@ int dram_init_banksize(void)
>>   	debug("Couldn't use ATAG (%d) to detect DDR layout, falling back...\n",
>>   	      ret);
>>   
>> -	/* Reserve 0x200000 for ATF bl31 */
>> -	gd->bd->bi_dram[0].start = 0x200000;
>> +	/* Reserve 2M for ATF bl31 */
>> +	gd->bd->bi_dram[0].start = CFG_SYS_SDRAM_BASE + SZ_2M;
>>   	gd->bd->bi_dram[0].size = top - gd->bd->bi_dram[0].start;
>>   
>>   	/* Add usable memory beyond the blob of space for peripheral near 4GB */
>> @@ -332,7 +332,7 @@ int dram_init_banksize(void)
>>   		gd->bd->bi_dram[0].size = 0x8400000;
>>   		/* Reserve 32M for OPTEE with TA */
>>   		gd->bd->bi_dram[1].start = CFG_SYS_SDRAM_BASE
>> -					+ gd->bd->bi_dram[0].size + 0x2000000;
>> +					+ gd->bd->bi_dram[0].size + SZ_32M;
>>   		gd->bd->bi_dram[1].size = top - gd->bd->bi_dram[1].start;
>>   	}
>>   #else