[PATCH v1 17/24] kvm: arm64: Add __hyp_pa_symbol helper macro

[Quentin Perret]

Hey David,

On Monday 09 Nov 2020 at 11:32:26 (+0000), David Brazdil wrote:
> Add helper macro for computing the PA of a kernel symbol in nVHE hyp
> code. This will be useful for computing the PA of a PSCI CPU_ON entry
> point.
> 
> Signed-off-by: David Brazdil <dbrazdil at google.com>
> ---
>  arch/arm64/kvm/hyp/nvhe/psci.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/arm64/kvm/hyp/nvhe/psci.c b/arch/arm64/kvm/hyp/nvhe/psci.c
> index b0b5df590ba5..7510b9e174e9 100644
> --- a/arch/arm64/kvm/hyp/nvhe/psci.c
> +++ b/arch/arm64/kvm/hyp/nvhe/psci.c
> @@ -20,6 +20,16 @@ s64 hyp_physvirt_offset;
>  
>  #define __hyp_pa(x) ((phys_addr_t)((x)) + hyp_physvirt_offset)
>  
> +#define __hyp_pa_symbol(sym)					\
> +	({							\
> +		extern char sym[];				\
> +		unsigned long kern_va;				\
> +								\
> +		asm volatile("ldr %0, =%1" : "=r" (kern_va)	\
> +					   : "S" (sym));	\
> +		kern_va - kimage_voffset;			\
> +	})
> +

Could this be simplified to __hyp_pa(hyp_symbol_addr(sym))? That would
avoid the dependency on kimage_voffset.

Thanks,
Quentin