[U-Boot] [PATCH v2] rockchip: Reconfigure the malloc based to point to system memory

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 01-10-15 20:51, Sjoerd Simons wrote:
> When malloc_base initially gets setup in the SPL it is based on the
> current (early) stack pointer, which for rockchip is pointing into SRAM.
> This means simple memory allocations happen in SRAM space, which is
> somewhat unfortunate. Specifically a bounce buffer for the mmc allocated
> in SRAM space seems to cause the mmc engine to stall/fail causing
> timeouts and a failure to load the main u-boot image.
>
> To resolve this, reconfigure the malloc_base to start at the relocated
> stack pointer after DRAM  has been setup.
>
> For reference, things did work fine on rockchip before 596380db was
> merged to fix memalign_simple due to a combination of rockchip SDRAM
> starting at address 0 and the dw_mmc driver not checking errors from
> bounce_buffer_start. As a result, when a bounce buffer needed to be
> allocated mem_align simple would fail and return NULL. The mmc driver
> ignored the error and happily continued with the bounce buffer address
> being set to 0, which just happened to work fine..
>
> Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>

Looks good to me, with the caveat that we really should do something
better (and revert this one) for v2016.01:

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans


>
> ---
> A potentially better fix for this issue would be to reconfigure the
> malloc_base in spl_relocate_stack_gd following the same steps as is done
> for the initial setup. However at this point in the release cycle i
> preferred to do a minimal rockchip only fix (so those boards become
> bootable again) for this issue to minimize the potential impact on other
> boards.
>
> Changes in v2:
> - Also gd->malloc_ptr to 0 to not waste any potential space
>
>   arch/arm/mach-rockchip/board-spl.c | 5 +++++
>   1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm/mach-rockchip/board-spl.c b/arch/arm/mach-rockchip/board-spl.c
> index a241d96..982a1d9 100644
> --- a/arch/arm/mach-rockchip/board-spl.c
> +++ b/arch/arm/mach-rockchip/board-spl.c
> @@ -217,6 +217,11 @@ void board_init_f(ulong dummy)
>   		debug("DRAM init failed: %d\n", ret);
>   		return;
>   	}
> +
> +	/* Now that DRAM is initialized setup base pointer for simple malloc
> +	 * into RAM */
> +	gd->malloc_base = CONFIG_SPL_STACK_R_ADDR;
> +	gd->malloc_ptr = 0;
>   }
>
>   static int setup_led(void)
>