[U-Boot] [PATCH] mach-stm32: Fix mpu region's attribute for STM32H7

[Patrice CHOTARD]

Hi Vikas

On 11/14/2017 03:16 AM, Vikas MANOCHA wrote:
> Hi Patrice,
> 
>> -----Original Message-----
>> From: Patrice CHOTARD
>> Sent: Monday, November 13, 2017 8:26 AM
>> To: u-boot at lists.denx.de; albert.u.boot at aribaud.net; sjg at chromium.org; Vikas MANOCHA <vikas.manocha at st.com>
>> Cc: Patrice CHOTARD <patrice.chotard at st.com>; Patrick DELAUNAY <patrick.delaunay at st.com>; Christophe KERELLO
>> <christophe.kerello at st.com>
>> Subject: [PATCH] mach-stm32: Fix mpu region's attribute for STM32H7
>>
>> From: Patrice Chotard <patrice.chotard at st.com>
>>
>> The SDRAM region was setup with the wrong attributes.
>> It must be set to :
>>    _ XN_EN (Execution of an instruction fetched from this region permitted)
>>    _ O_I_WB_RD_WR_ALLOC (Outer and inner write-back, write and read allocate)
>>
> 
> H7 mpu configuration seems same as F7, can we have one config for F7 & H7.

Between F7 and H7, there is one difference regarding the F7's region 3 
which is not needed on H7 because FMC/QSPI registers are located inside 
H7's region 2.

Just one question about F7's region 1, why is it only 512MB and not 1GB 
long, to include ITCM and DTCM area ? (see Embedded SRAM chapter of 
RM0385 Reference manual)

Nevertheless, i just notice that for H7, i can remove region 1 which 
overlaps region 0 with exactly the same attribute.

Thanks

> 
>> This fixes hard fault when trying to load and execute kernel linux in this area.
>>
>> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
> 
> In any case,
> Reviewed-by: Vikas Manocha <vikas.manocha at st.com>
> 
> Cheers,
> Vikas
> 
>> ---
>>   arch/arm/mach-stm32/stm32h7/soc.c | 9 ++++++---
>>   1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm/mach-stm32/stm32h7/soc.c b/arch/arm/mach-stm32/stm32h7/soc.c
>> index 692dbcc..e0d3f11 100644
>> --- a/arch/arm/mach-stm32/stm32h7/soc.c
>> +++ b/arch/arm/mach-stm32/stm32h7/soc.c
>> @@ -30,9 +30,12 @@ int arch_cpu_init(void)
>>   		{ 0x00000000, REGION_0, XN_DIS, PRIV_RW_USR_RW,
>>   		O_I_WB_RD_WR_ALLOC, REGION_4GB },
>>
>> -		/* Code area, executable & strongly ordered */
>> -		{ 0xD0000000, REGION_1, XN_EN, PRIV_RW_USR_RW,
>> -		STRONG_ORDER, REGION_8MB },
>> +		/*
>> +		 * Code area, executable, Outer and inner write-back,
>> +		 * no write allocate
>> +		 */
>> +		{ 0xD0000000, REGION_1, XN_DIS, PRIV_RW_USR_RW,
>> +		O_I_WB_RD_WR_ALLOC, REGION_32MB },
>>
>>   		/* Device area in all H7 : Not executable */
>>   		{ 0x40000000, REGION_2, XN_EN, PRIV_RW_USR_RW,
>> --
>> 1.9.1
>