Re: [PATCH] ARM: rcar-gen2: Do not setup timer in non-secure mode

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 10-12-2013 19:53, Ben Dooks wrote:

> If the system has been started in non-secure mode, then the ARM generic
> timer is not configurable during the kernel initialisation. Currently
> the only thing we can check for is if the timer has been correctly
> configured during the boot process.

> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
> Reviewed-by: Ian Molton <ian.molton@codethink.co.uk>
> ---
>   arch/arm/mach-shmobile/setup-rcar-gen2.c | 18 +++++++++++++-----
>   1 file changed, 13 insertions(+), 5 deletions(-)

> diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
> index 5734c24..6b7b7f1 100644
> --- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
> +++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
> @@ -78,12 +78,20 @@ void __init rcar_gen2_timer_init(void)
>   	/* Remap "armgcnt address map" space */
>   	base = ioremap(0xe6080000, PAGE_SIZE);
>
> -	/* Update registers with correct frequency */
> -	iowrite32(freq, base + CNTFID0);
> -	asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
> +	/* Update the timer if it is either not running, or is not at the
> +	 * right frequency. The timer is only configurable in secure mode
> +	 * so this avoids an abort if the loader started the timer and
> +	 * started the kernel in non-secure mode. */

    The preferred style of the multi-line comments is this:

/*
  * bla
  * bla
  */

WBR, Sergei