Re: [PATCH v2] firmware/psci: add support for SYSTEM_RESET2

[Michal Simek <michal.simek@xilinx.com>]

Hi Sudeep,

On 2.5.2018 12:30, Sudeep Holla wrote:
> PSCI v1.1 introduced SYSTEM_RESET2 to allow both architectural resets
> where the semantics are described by the PSCI specification itself as
> well as vendor-specific resets. Currently only system warm reset
> semantics is defined as part of architectural resets by the specification.
> 
> This patch implements support for SYSTEM_RESET2 by making using of
> reboot_mode passed by the reboot infrastructure in the kernel.
> 
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---
>  drivers/firmware/psci.c   | 21 +++++++++++++++++++++
>  include/uapi/linux/psci.h |  2 ++
>  2 files changed, 23 insertions(+)
> 
> v1->v2:
> 	- Added mising static anotation to psci_system_reset2_supported
> 	- Added missing ')' in the comment
> 
> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
> index c80ec1d03274..91748725534e 100644
> --- a/drivers/firmware/psci.c
> +++ b/drivers/firmware/psci.c
> @@ -88,6 +88,7 @@ static u32 psci_function_id[PSCI_FN_MAX];
>  				PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
> 
>  static u32 psci_cpu_suspend_feature;
> +static bool psci_system_reset2_supported;
> 
>  static inline bool psci_has_ext_power_state(void)
>  {
> @@ -253,6 +254,15 @@ static int get_set_conduit_method(struct device_node *np)
> 
>  static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
>  {
> +	if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&

I am curious about this reboot_mode setup. I have grepped the kernel and
reboot_mode is setup via kernel parameters at boot time.
Shouldn't user decide what reboot type wants to do?

Thanks,
Michal