[PATCH 2/4] MIPS: ath79: pbl: import hornet_1_1_war routine from U-Boot_mod

[Yegor Yefremov]

On Thu, Feb 25, 2016 at 10:14 AM, Antony Pavlov <antonynpavlov at gmail.com> wrote:
> U-Boot_mod is a popular bootloader for Atheros AR93xx chips,
> please see https://github.com/pepe2k/u-boot_mod for details.
>
> It's reasonable to import some lowlevel AR9331 initialization
> code from U-Boot_mod.
>
> AR9331 (Hornet) 1.1 currently needs an additional
> reset at 1st boot. This patch imports necessary code
> from u-boot_mod/u-boot/cpu/mips/start_bootstrap.S.
>
> Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>

Reviewed-by: Yegor Yefremov <yegorslists at googlemail.com>

> ---
>  arch/mips/mach-ath79/include/mach/pbl_macros.h | 43 ++++++++++++++++++++++++++
>  1 file changed, 43 insertions(+)
>
> diff --git a/arch/mips/mach-ath79/include/mach/pbl_macros.h b/arch/mips/mach-ath79/include/mach/pbl_macros.h
> index 810f49d..24cfd60 100644
> --- a/arch/mips/mach-ath79/include/mach/pbl_macros.h
> +++ b/arch/mips/mach-ath79/include/mach/pbl_macros.h
> @@ -223,4 +223,47 @@
>         .set    pop
>  .endm
>
> +.macro hornet_1_1_war
> +       .set push
> +       .set noreorder
> +
> +/*
> + * WAR: Hornet 1.1 currently need a reset once we boot to let the resetb has
> + *      enough time to stable, so that trigger reset at 1st boot, system team
> + *      is investigaing the issue, will remove in short
> + */
> +
> +       li  t7, 0xbd000000
> +       lw  t8, 0(t7)
> +       li  t9, 0x12345678
> +
> +       /* if value of 0xbd000000 != 0x12345678, go to do_reset */
> +       bne t8, t9, do_reset
> +        nop
> +
> +       li  t9, 0xffffffff
> +       sw  t9, 0(t7)
> +       b   normal_path
> +        nop
> +
> +do_reset:
> +       /* put 0x12345678 into 0xbd000000 */
> +       sw  t9, 0(t7)
> +
> +       /* reset register 0x1806001c */
> +       li  t7, 0xb806001c
> +       lw  t8, 0(t7)
> +       /* bit24, fullchip reset */
> +       li  t9, 0x1000000
> +       or  t8, t8, t9
> +       sw  t8, 0(t7)
> +
> +do_reset_loop:
> +       b   do_reset_loop
> +        nop
> +
> +normal_path:
> +       .set    pop
> +.endm
> +
>  #endif /* __ASM_MACH_ATH79_PBL_MACROS_H */
> --
> 2.7.0
>