[PATCHv2 10/12] drivers: psci: support native SMC{32,64} calls

Catalin Marinas catalin.marinas at arm.com
Mon May 18 10:43:38 PDT 2015


On Mon, May 18, 2015 at 11:38:21AM +0100, Mark Rutland wrote:
> A 32-bit OS cannot make calls with SMC64 IDs, while a 64-bit OS must
> invoke some PSCI functions with SMC64 IDs.
> 
> This patch introduces and makes use of a new macro to choose the
> appropriate IDs based on the register width of the OS, which will allow
> 32-bit callers to use the PSCI client code.
> 
> Signed-off-by: Mark Rutland <mark.rutland at arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> ---
>  drivers/firmware/psci.c | 25 +++++++++++++++++++------
>  1 file changed, 19 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
> index 792f4a7..e071ada 100644
> --- a/drivers/firmware/psci.c
> +++ b/drivers/firmware/psci.c
> @@ -27,6 +27,18 @@
>  #include <asm/smp_plat.h>
>  
>  /*
> + * While a 64-bit OS can make calls with SMC32 calling conventions, for some
> + * calls it is necessary to use SMC64 to pass or return 64-bit values. For such
> + * calls PSCI_0_2_FN_NATIVE(x) will choose the appropriate (native-width)
> + * function ID.
> + */
> +#ifdef CONFIG_64BIT
> +#define PSCI_0_2_FN_NATIVE(name)	PSCI_0_2_FN_##name
> +#else
> +#define PSCI_0_2_FN_NATIVE(name)	PSCI_0_2_FN64_##name
> +#endif
> +
> +/*
>   * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
>   * calls to its resident CPU, so we must avoid issuing those. We never migrate
>   * a Trusted OS even if it claims to be capable of migration -- doing so will
> @@ -121,8 +133,8 @@ static int psci_migrate(unsigned long cpuid)
>  static int psci_affinity_info(unsigned long target_affinity,
>  		unsigned long lowest_affinity_level)
>  {
> -	return invoke_psci_fn(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity,
> -			      lowest_affinity_level, 0);
> +	return invoke_psci_fn(PSCI_0_2_FN_NATIVE(AFFINITY_INFO),
> +			      target_affinity, lowest_affinity_level, 0);

That's wrong ;).

-- 
Catalin



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