[U-Boot] [PATCH v3 11/14] tegra20: Remove CPU init code from tegra20 u-boot

Allen Martin amartin at nvidia.com
Tue Jun 12 00:53:53 CEST 2012


On Sat, Jun 09, 2012 at 12:19:48PM -0700, Simon Glass wrote:
> Hi Allen,
> 
> On Fri, Jun 8, 2012 at 2:16 PM, Allen Martin <amartin at nvidia.com<mailto:amartin at nvidia.com>> wrote:
> This code is now included in the tegra20 SPL
> 
> Signed-off-by: Allen Martin <amartin at nvidia.com<mailto:amartin at nvidia.com>>
> ---
>  arch/arm/cpu/armv7/start.S          |    2 -
>  arch/arm/cpu/tegra20-common/ap20.c  |  258 +----------------------------------
>  arch/arm/cpu/tegra20-common/board.c |   23 +---
>  include/configs/tegra20-common.h    |    4 -
>  4 files changed, 4 insertions(+), 283 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
> index 5b88c55..786152f 100644
> --- a/arch/arm/cpu/armv7/start.S
> +++ b/arch/arm/cpu/armv7/start.S
> @@ -347,27 +114,8 @@ void init_pmc_scratch(void)
>        writel(odmdata, &pmc->pmc_scratch20);
>  }
> 
> -void tegra20_start(void)
> +void lowlevel_init(void)
>  {
> -       struct pmux_tri_ctlr *pmt = (struct pmux_tri_ctlr *)NV_PA_APB_MISC_BASE;
> -
> -       /* If we are the AVP, start up the first Cortex-A9 */
> -       if (!ap20_cpu_is_cortexa9()) {
> -               /* enable JTAG */
> -               writel(0xC0, &pmt->pmt_cfg_ctl);
> -
> -               /*
> -                * If we are ARM7 - give it a different stack. We are about to
> -                * start up the A9 which will want to use this one.
> -                */
> -               asm volatile("mov       sp, %0\n"
> -                       : : "r"(AVP_EARLY_BOOT_STACK_LIMIT));
> -
> -               start_cpu((u32)_start);
> -               halt_avp();
> -               /* not reached */
> -       }
> -
>        /* Init PMC scratch memory */
>        init_pmc_scratch();
> 
> There is a FIXME comment immediately after this:
> 
> /* FIXME: should have ap20's L2 disabled too? */
> 
> Does this still apply?

I'm not sure what the origin of that comment was, but AFAIK the L2
will always be disabled on reset until we explicitly enable it, so I'm
not sure what the comment is referring to.

> 
> diff --git a/arch/arm/cpu/tegra20-common/board.c b/arch/arm/cpu/tegra20-common/board.c
> index 70e5373..74610e5 100644
> --- a/arch/arm/cpu/tegra20-common/board.c
> +++ b/arch/arm/cpu/tegra20-common/board.c
> @@ -23,12 +23,12 @@
> 
>  #include <common.h>
>  #include <asm/io.h>
> -#include <asm/arch/ap20.h>
>  #include <asm/arch/clock.h>
>  #include <asm/arch/funcmux.h>
>  #include <asm/arch/pmc.h>
>  #include <asm/arch/sys_proto.h>
>  #include <asm/arch/tegra20.h>
> +#include <asm/arch/warmboot.h>
> 
>  DECLARE_GLOBAL_DATA_PTR;
> 
> @@ -85,27 +85,6 @@ int checkboard(void)
>  }
>  #endif /* CONFIG_DISPLAY_BOARDINFO */
> 
> -#ifdef CONFIG_ARCH_CPU_INIT
> -/*
> - * Note this function is executed by the ARM7TDMI AVP. It does not return
> - * in this case. It is also called once the A9 starts up, but does nothing in
> - * that case.
> - */
> -int arch_cpu_init(void)
> -{
> -       /* Fire up the Cortex A9 */
> -       tegra20_start();
> -
> -       /* We didn't do this init in start.S, so do it now */
> -       cpu_init_cp15();
> -
> -       /* Initialize essential common plls */
> -       clock_early_init();
> 
> What happens to clock_early_init() with this patch? Is it called somewhere else?

Yes, it gets called from the SPL now in board_init_r()
arch/arm/cpu/arm720t/tegra20/spl.c 

-Allen
-- 
nvpublic


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