[v3,2/2] arm: stm32mp: activate data cache on DDR in SPL

Activate cache on DDR to improves the accesses to DDR used by SPL:
- CONFIG_SPL_BSS_START_ADDR
- CONFIG_SYS_SPL_MALLOC_START

Cache is configured only when DDR is fully initialized,
to avoid speculative access and issue in get_ram_size().
Data cache is deactivated at the end of SPL, to flush the data cache
and the TLB.

Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
---

Changes in v3:
- remove debug message "bye"

Changes in v2:
- new

 arch/arm/mach-stm32mp/spl.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

Hi

One typo below

On 4/24/20 8:24 PM, Patrick Delaunay wrote:
> Activate cache on DDR to improves the accesses to DDR used by SPL:
s/improves/improve
> - CONFIG_SPL_BSS_START_ADDR
> - CONFIG_SYS_SPL_MALLOC_START
>
> Cache is configured only when DDR is fully initialized,
> to avoid speculative access and issue in get_ram_size().
> Data cache is deactivated at the end of SPL, to flush the data cache
> and the TLB.
>
> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> ---
>
> Changes in v3:
> - remove debug message "bye"
>
> Changes in v2:
> - new
>
>  arch/arm/mach-stm32mp/spl.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
>
> diff --git a/arch/arm/mach-stm32mp/spl.c b/arch/arm/mach-stm32mp/spl.c
> index f85391c6af..e50a21c3b7 100644
> --- a/arch/arm/mach-stm32mp/spl.c
> +++ b/arch/arm/mach-stm32mp/spl.c
> @@ -4,6 +4,7 @@
>   */
>  
>  #include <common.h>
> +#include <cpu_func.h>
>  #include <dm.h>
>  #include <hang.h>
>  #include <spl.h>
> @@ -115,4 +116,22 @@ void board_init_f(ulong dummy)
>  		printf("DRAM init failed: %d\n", ret);
>  		hang();
>  	}
> +
> +	/*
> +	 * activate cache on DDR only when DDR is fully initialized
> +	 * to avoid speculative access and issue in get_ram_size()
> +	 */
> +	if (!CONFIG_IS_ENABLED(SYS_DCACHE_OFF))
> +		mmu_set_region_dcache_behaviour(STM32_DDR_BASE, STM32_DDR_SIZE,
> +						DCACHE_DEFAULT_OPTION);
> +}
> +
> +void spl_board_prepare_for_boot(void)
> +{
> +	dcache_disable();
> +}
> +
> +void spl_board_prepare_for_boot_linux(void)
> +{
> +	dcache_disable();
>  }

Reviewed-by: Patrice Chotard <patrice.chotard at st.com>

Thanks