Re: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
On Thu, Apr 11, 2019 at 09:26:37PM +0300, Aaro Koskinen wrote:
> Hi,
>
> On Thu, Apr 11, 2019 at 05:49:36PM +0100, Sudeep Holla wrote:
> > On Thu, Apr 11, 2019 at 11:42:28AM +, Koskinen, Aaro (Nokia - FI/Espoo)
> > wrote:
> > > From: Sudeep Holla [sudeep.ho...@arm.com]:
> > > > static void psci_sys_reset(enum reboot_mode reboot_mode, const char
> > > > *cmd)
> > > > {
> > > > + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT)
> > > > &&
> > >
> > > I would omit the REBOOT_SOFT here.
> >
> > I included REBOOT_SOFT for 2 reasons:
> > 1. drivers/firmware/efi/reboot.c - efi_reboot treats WARM and SOFT reboots
> > same
> > 2. If the vendors specific reboots are added and handled in EFI, I assume it
> >will be categorised under REBOOT_SOFT.
> >
> > If that's wrong I can drop REBOOT_SOFT.
>
> Not a big issue, but it's just unclear what SOFT means. WARM at least maps
> nicely to the PSCI spec.
>
OK, I will keep it for now.
> > > > + psci_system_reset2_supported)
> > > > + /*
> > > > +* reset_type[31] = 0 (architectural)
> > > > +* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> > > > +* cookie = 0 (ignored by the implementation)
> > > > +*/
> > > > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0,
> > > > 0, 0);
> > > > +
> > > >invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
> > >
> > > Use else here, so that we fall back to system halt if SYSTEM_RESET2 fails.
> >
> > Will that not change current behaviour ? IOW, is that expected behaviour ?
> > I am not sure if halt can be prefer over cold reboot in absence of warm/soft
> > reboot when the system is request to reboot. From PSCI perspective, since
> > SYSTEM_RESET is mandatory I prefer that unless Linux has any restriction
> > on this behaviour.
>
> Hmm, so does it mean that even if firmware tells that SYSTEM_RESET2
> is implemented it does not imply that SYSTEM_WARM_RESET is
> available? I.e. the firmware could choose to implement only some
> vendor-specific resets but not architectural ones. In that case, could
> we fall back to cold reset only if NOT_SUPPORTED is returned? My point
> is that if the warm reset fails unexpectedly, we should halt the system
> like we do if the cold reset fails.
>
OK, I understood. Sorry I was under the assumption that architectural
reset was mandatory if SYSTEM_RESET2 is implemented. I checked the PSCI
specification and I am wrong. So I am happy to add else as per your
suggestion.
--
Regards,
Sudeep
Re: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
Hi,
On Thu, Apr 11, 2019 at 05:49:36PM +0100, Sudeep Holla wrote:
> On Thu, Apr 11, 2019 at 11:42:28AM +, Koskinen, Aaro (Nokia - FI/Espoo)
> wrote:
> > From: Sudeep Holla [sudeep.ho...@arm.com]:
> > > static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
> > > {
> > > + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
> >
> > I would omit the REBOOT_SOFT here.
>
> I included REBOOT_SOFT for 2 reasons:
> 1. drivers/firmware/efi/reboot.c - efi_reboot treats WARM and SOFT reboots
> same
> 2. If the vendors specific reboots are added and handled in EFI, I assume it
>will be categorised under REBOOT_SOFT.
>
> If that's wrong I can drop REBOOT_SOFT.
Not a big issue, but it's just unclear what SOFT means. WARM at least maps
nicely to the PSCI spec.
> > > + psci_system_reset2_supported)
> > > + /*
> > > +* reset_type[31] = 0 (architectural)
> > > +* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> > > +* cookie = 0 (ignored by the implementation)
> > > +*/
> > > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0,
> > > 0);
> > > +
> > >invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
> >
> > Use else here, so that we fall back to system halt if SYSTEM_RESET2 fails.
>
> Will that not change current behaviour ? IOW, is that expected behaviour ?
> I am not sure if halt can be prefer over cold reboot in absence of warm/soft
> reboot when the system is request to reboot. From PSCI perspective, since
> SYSTEM_RESET is mandatory I prefer that unless Linux has any restriction
> on this behaviour.
Hmm, so does it mean that even if firmware tells that SYSTEM_RESET2
is implemented it does not imply that SYSTEM_WARM_RESET is
available? I.e. the firmware could choose to implement only some
vendor-specific resets but not architectural ones. In that case, could
we fall back to cold reset only if NOT_SUPPORTED is returned? My point
is that if the warm reset fails unexpectedly, we should halt the system
like we do if the cold reset fails.
A.
Re: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
On Thu, Apr 11, 2019 at 11:42:28AM +, Koskinen, Aaro (Nokia - FI/Espoo)
wrote:
> Hi,
>
> From: Sudeep Holla [sudeep.ho...@arm.com]:
> > static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
> > {
> > + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
>
> I would omit the REBOOT_SOFT here.
>
I included REBOOT_SOFT for 2 reasons:
1. drivers/firmware/efi/reboot.c - efi_reboot treats WARM and SOFT reboots same
2. If the vendors specific reboots are added and handled in EFI, I assume it
will be categorised under REBOOT_SOFT.
If that's wrong I can drop REBOOT_SOFT.
> > + psci_system_reset2_supported)
> > + /*
> > +* reset_type[31] = 0 (architectural)
> > +* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> > +* cookie = 0 (ignored by the implementation)
> > +*/
> > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
> > +
> >invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
>
> Use else here, so that we fall back to system halt if SYSTEM_RESET2 fails.
>
Will that not change current behaviour ? IOW, is that expected behaviour ?
I am not sure if halt can be prefer over cold reboot in absence of warm/soft
reboot when the system is request to reboot. From PSCI perspective, since
SYSTEM_RESET is mandatory I prefer that unless Linux has any restriction
on this behaviour.
--
Regards,
Sudeep
Re: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
On Thu, Apr 11, 2019 at 12:03:04PM +0100, Mark Rutland wrote:
> On Thu, Apr 11, 2019 at 11:33:46AM +0100, 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
> > Cc: Lorenzo Pieralisi
> > Signed-off-by: Sudeep Holla
> > ---
> > drivers/firmware/psci.c | 21 +
> > include/uapi/linux/psci.h | 2 ++
> > 2 files changed, 23 insertions(+)
> >
> > Resending [1] based on the request. I hope to get some testing this time.
> > Last time Xilinx asked multiple times but never got any review or testing
> > https://lore.kernel.org/lkml/1525257003-8608-1-git-send-email-sudeep.ho...@arm.com/
> >
> > 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) &&
> > + psci_system_reset2_supported)
> > + /*
> > +* reset_type[31] = 0 (architectural)
> > +* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> > +* cookie = 0 (ignored by the implementation)
> > +*/
> > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
>
> Since the comment and invocation span multiple lines, could we please
> wrap them in braces?
>
Yes, that would be better, will update it.
> Other than that, this looks good to me, so:
>
> Acked-by: Mark Rutland
>
Thanks.
--
Regards,
Sudeep
RE: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
Hi,
From: Sudeep Holla [sudeep.ho...@arm.com]:
> static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
> {
> + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
I would omit the REBOOT_SOFT here.
> + psci_system_reset2_supported)
> + /*
> +* reset_type[31] = 0 (architectural)
> +* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> +* cookie = 0 (ignored by the implementation)
> +*/
> + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
> +
>invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
Use else here, so that we fall back to system halt if SYSTEM_RESET2 fails.
A.
Re: [RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
On Thu, Apr 11, 2019 at 11:33:46AM +0100, 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
> Cc: Lorenzo Pieralisi
> Signed-off-by: Sudeep Holla
> ---
> drivers/firmware/psci.c | 21 +
> include/uapi/linux/psci.h | 2 ++
> 2 files changed, 23 insertions(+)
>
> Resending [1] based on the request. I hope to get some testing this time.
> Last time Xilinx asked multiple times but never got any review or testing
> https://lore.kernel.org/lkml/1525257003-8608-1-git-send-email-sudeep.ho...@arm.com/
>
> 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) &&
> + psci_system_reset2_supported)
> + /*
> + * reset_type[31] = 0 (architectural)
> + * reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
> + * cookie = 0 (ignored by the implementation)
> + */
> + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
Since the comment and invocation span multiple lines, could we please
wrap them in braces?
Other than that, this looks good to me, so:
Acked-by: Mark Rutland
... I assume that Aaro will give this some testing.
Thanks,
Mark.
> +
> invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
> }
>
> @@ -451,6 +461,16 @@ static const struct platform_suspend_ops
> psci_suspend_ops = {
> .enter = psci_system_suspend_enter,
> };
>
> +static void __init psci_init_system_reset2(void)
> +{
> + int ret;
> +
> + ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
> +
> + if (ret != PSCI_RET_NOT_SUPPORTED)
> + psci_system_reset2_supported = true;
> +}
> +
> static void __init psci_init_system_suspend(void)
> {
> int ret;
> @@ -588,6 +608,7 @@ static int __init psci_probe(void)
> psci_init_smccc();
> psci_init_cpu_suspend();
> psci_init_system_suspend();
> + psci_init_system_reset2();
> }
>
> return 0;
> diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h
> index b3bcabe380da..5b0ba0062541 100644
> --- a/include/uapi/linux/psci.h
> +++ b/include/uapi/linux/psci.h
> @@ -49,8 +49,10 @@
>
> #define PSCI_1_0_FN_PSCI_FEATURESPSCI_0_2_FN(10)
> #define PSCI_1_0_FN_SYSTEM_SUSPEND PSCI_0_2_FN(14)
> +#define PSCI_1_1_FN_SYSTEM_RESET2PSCI_0_2_FN(18)
>
> #define PSCI_1_0_FN64_SYSTEM_SUSPEND PSCI_0_2_FN64(14)
> +#define PSCI_1_1_FN64_SYSTEM_RESET2 PSCI_0_2_FN64(18)
>
> /* PSCI v0.2 power state encoding for CPU_SUSPEND function */
> #define PSCI_0_2_POWER_STATE_ID_MASK 0x
> --
> 2.17.1
>
[RESEND][PATCH v2] firmware/psci: add support for SYSTEM_RESET2
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
Cc: Lorenzo Pieralisi
Signed-off-by: Sudeep Holla
---
drivers/firmware/psci.c | 21 +
include/uapi/linux/psci.h | 2 ++
2 files changed, 23 insertions(+)
Resending [1] based on the request. I hope to get some testing this time.
Last time Xilinx asked multiple times but never got any review or testing
https://lore.kernel.org/lkml/1525257003-8608-1-git-send-email-sudeep.ho...@arm.com/
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) &&
+ psci_system_reset2_supported)
+ /*
+* reset_type[31] = 0 (architectural)
+* reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
+* cookie = 0 (ignored by the implementation)
+*/
+ invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
+
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
}
@@ -451,6 +461,16 @@ static const struct platform_suspend_ops psci_suspend_ops
= {
.enter = psci_system_suspend_enter,
};
+static void __init psci_init_system_reset2(void)
+{
+ int ret;
+
+ ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
+
+ if (ret != PSCI_RET_NOT_SUPPORTED)
+ psci_system_reset2_supported = true;
+}
+
static void __init psci_init_system_suspend(void)
{
int ret;
@@ -588,6 +608,7 @@ static int __init psci_probe(void)
psci_init_smccc();
psci_init_cpu_suspend();
psci_init_system_suspend();
+ psci_init_system_reset2();
}
return 0;
diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h
index b3bcabe380da..5b0ba0062541 100644
--- a/include/uapi/linux/psci.h
+++ b/include/uapi/linux/psci.h
@@ -49,8 +49,10 @@
#define PSCI_1_0_FN_PSCI_FEATURES PSCI_0_2_FN(10)
#define PSCI_1_0_FN_SYSTEM_SUSPEND PSCI_0_2_FN(14)
+#define PSCI_1_1_FN_SYSTEM_RESET2 PSCI_0_2_FN(18)
#define PSCI_1_0_FN64_SYSTEM_SUSPEND PSCI_0_2_FN64(14)
+#define PSCI_1_1_FN64_SYSTEM_RESET2PSCI_0_2_FN64(18)
/* PSCI v0.2 power state encoding for CPU_SUSPEND function */
#define PSCI_0_2_POWER_STATE_ID_MASK 0x
--
2.17.1
