[PATCH v3 05/15] board: ns3: add api to save boot parameters passed from BL31

[Simon Glass]

On Wed, 10 Jun 2020 at 04:41, Rayagonda Kokatanur
<rayagonda.kokatanur at broadcom.com> wrote:
>
> From: Abhishek Shah <abhishek.shah at broadcom.com>
>
> Add API to save boot parameters passed from BL31
>
> Use assembly implementation of save_boot_params instead of c function.
> Because generally ATF does not set up SP_EL2 on exiting.
> Thus, usage of a C function immediately after exiting with no stack
> setup done by ATF explicitly, may cause SP_EL2 to be not sane,
> which in turn causes a crash if this boot was not lucky to get
> an SP_EL2 in valid range. Replace C implementation with assembly one
> which does not use stack this early, and let u-boot to set up its stack
> later.

Can this be fixed in ATF?

>
> Signed-off-by: Abhishek Shah <abhishek.shah at broadcom.com>
> Signed-off-by: Rajesh Ravi <rajesh.ravi at broadcom.com>
> Signed-off-by: Vladimir Olovyannikov <vladimir.olovyannikov at broadcom.com>
> Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur at broadcom.com>
> ---
>  arch/arm/cpu/armv8/bcmns3/lowlevel.S         |  9 +++++++
>  arch/arm/include/asm/arch-bcmns3/bl33_info.h | 26 ++++++++++++++++++++
>  board/broadcom/bcmns3/ns3.c                  | 10 ++++++++
>  3 files changed, 45 insertions(+)
>  create mode 100644 arch/arm/include/asm/arch-bcmns3/bl33_info.h
>

Reviewed-by: Simon Glass <sjg at chromium.org>

> diff --git a/board/broadcom/bcmns3/ns3.c b/board/broadcom/bcmns3/ns3.c
> index e38156723c..5e644bd466 100644
> --- a/board/broadcom/bcmns3/ns3.c
> +++ b/board/broadcom/bcmns3/ns3.c
> @@ -8,6 +8,7 @@
>  #include <asm/io.h>
>  #include <asm/system.h>
>  #include <asm/armv8/mmu.h>
> +#include <asm/arch-bcmns3/bl33_info.h>
>
>  static struct mm_region ns3_mem_map[] = {
>         {
> @@ -33,8 +34,17 @@ struct mm_region *mem_map = ns3_mem_map;
>
>  DECLARE_GLOBAL_DATA_PTR;
>
> +/*
> + * Force the bl33_info to the data-section, as .bss will not be valid
> + * when save_boot_params is invoked.
> + */
> +struct bl33_info *bl33_info __section(".data");
> +
>  int board_init(void)
>  {
> +       if (bl33_info->version != BL33_INFO_VERSION)
> +               printf("*** warning: ATF BL31 and u-boot not in sync! ***\n");

Shouldn't this be a fatal error?


> +
>         return 0;
>  }
>
> --
> 2.17.1
>