Re: [PATCH 1/2] ARM: zynq: support smp in thumb mode

[Michal Simek]

On 06. 08. 19 5:07, Luis Araneda wrote:
> Add .arm directive to headsmp.S to ensure that the
> CPU starts in 32-bit ARM mode and the correct code
> size is copied on smp bring-up
> 
> Additionally, start secondary CPUs on secondary_startup_arm
> to automatically switch from ARM to thumb on a thumb kernel
> 
> Suggested-by: Michal Simek <michal.simek@xxxxxxxxxx>
> Signed-off-by: Luis Araneda <luaraneda@xxxxxxxxx>
> ---
>  arch/arm/mach-zynq/headsmp.S | 2 ++
>  arch/arm/mach-zynq/platsmp.c | 2 +-
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-zynq/headsmp.S b/arch/arm/mach-zynq/headsmp.S
> index ab85003cf9ad..3449e0d1f990 100644
> --- a/arch/arm/mach-zynq/headsmp.S
> +++ b/arch/arm/mach-zynq/headsmp.S
> @@ -7,6 +7,8 @@
>  #include <linux/init.h>
>  #include <asm/assembler.h>
>  
> +	.arm
> +
>  ENTRY(zynq_secondary_trampoline)
>  ARM_BE8(setend	be)				@ ensure we are in BE8 mode
>  	ldr	r0, zynq_secondary_trampoline_jump
> diff --git a/arch/arm/mach-zynq/platsmp.c b/arch/arm/mach-zynq/platsmp.c
> index a7cfe07156f4..38728badabd4 100644
> --- a/arch/arm/mach-zynq/platsmp.c
> +++ b/arch/arm/mach-zynq/platsmp.c
> @@ -81,7 +81,7 @@ EXPORT_SYMBOL(zynq_cpun_start);
>  
>  static int zynq_boot_secondary(unsigned int cpu, struct task_struct *idle)
>  {
> -	return zynq_cpun_start(__pa_symbol(secondary_startup), cpu);
> +	return zynq_cpun_start(__pa_symbol(secondary_startup_arm), cpu);
>  }
>  
>  /*
> 

It is really a question if this should go to stable tree. It is pretty
much new feature.
Will be good to also add link to similar patch for example this one
5616f36713ea77f57ae908bf2fef641364403c9f.

M