From: Oleksandr Tyshchenko <[email protected]>
If PSCI is available then most likely we are running on PSCI-enabled
U-Boot which, we assume, has already taken care of resetting CNTVOFF
and updating counter module before switching to non-secure mode
and we don't need to.
As the psci_smp_available() helper always returns false if CONFIG_SMP
is disabled, it can't be used safely as an indicator of PSCI usage.
For that reason, we check for the mandatory PSCI operation to be
available.
Please note, an extra check to prevent secure_cntvoff_init() from
being called for secondary CPUs in headsmp-apmu.S is not needed,
as SMP code for APMU based system is not executed if PSCI is in use.
Signed-off-by: Oleksandr Tyshchenko <[email protected]>
CC: Julien Grall <[email protected]>
---
You can find previous discussions here:
[v1] https://lkml.org/lkml/2019/4/17/810
[v2] https://lkml.org/lkml/2019/5/3/338
[v3] https://lkml.org/lkml/2019/5/10/415
[RFC] https://lkml.org/lkml/2019/5/10/473
Changes in v2:
- Clarify patch subject/description
- Don't use CONFIG_ARM_PSCI option, check whether the PSCI is available,
by using psci_smp_available()
- Check whether we are running on top of Xen, by using xen_domain()
Changes in v3:
- Don't check for the presence of Xen
Changes in v4:
- Don't use psci_smp_available() helper, check for psci_ops.cpu_on
directly
- Skip updating counter module if PSCI is available
---
arch/arm/mach-shmobile/setup-rcar-gen2.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index eea60b2..64e3abd 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -17,6 +17,7 @@
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
+#include <linux/psci.h>
#include <asm/mach/arch.h>
#include <asm/secure_cntvoff.h>
#include "common.h"
@@ -63,6 +64,15 @@ void __init rcar_gen2_timer_init(void)
void __iomem *base;
u32 freq;
+ /*
+ * If PSCI is available then most likely we are running on PSCI-enabled
+ * U-Boot which, we assume, has already taken care of resetting CNTVOFF
+ * and updating counter module before switching to non-secure mode
+ * and we don't need to.
+ */
+ if (psci_ops.cpu_on)
+ goto skip_update;
+
secure_cntvoff_init();
if (of_machine_is_compatible("renesas,r8a7745") ||
@@ -102,6 +112,7 @@ void __init rcar_gen2_timer_init(void)
iounmap(base);
+skip_update:
of_clk_init(NULL);
timer_probe();
}
--
2.7.4
Hi,
On 14/05/2019 17:06, Oleksandr Tyshchenko wrote:
> diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
> index eea60b2..64e3abd 100644
> --- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
> +++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
> @@ -17,6 +17,7 @@
> #include <linux/of.h>
> #include <linux/of_fdt.h>
> #include <linux/of_platform.h>
> +#include <linux/psci.h>
> #include <asm/mach/arch.h>
> #include <asm/secure_cntvoff.h>
> #include "common.h"
> @@ -63,6 +64,15 @@ void __init rcar_gen2_timer_init(void)
> void __iomem *base;
> u32 freq;
>
> + /*
> + * If PSCI is available then most likely we are running on PSCI-enabled
> + * U-Boot which, we assume, has already taken care of resetting CNTVOFF
> + * and updating counter module before switching to non-secure mode
> + * and we don't need to.
> + */
> + if (psci_ops.cpu_on) > + goto skip_update;
Are you sure this is working when ARM_PSCI_FW is not selected? Is it possible to
have a .config for RCAR without ARM_PSCI_FW?
Cheers,
--
Julien Grall
On 14.05.19 19:13, Julien Grall wrote:
> Hi,
Hi Julien
>
> On 14/05/2019 17:06, Oleksandr Tyshchenko wrote:
>> diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c
>> b/arch/arm/mach-shmobile/setup-rcar-gen2.c
>> index eea60b2..64e3abd 100644
>> --- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
>> +++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
>> @@ -17,6 +17,7 @@
>> #include <linux/of.h>
>> #include <linux/of_fdt.h>
>> #include <linux/of_platform.h>
>> +#include <linux/psci.h>
>> #include <asm/mach/arch.h>
>> #include <asm/secure_cntvoff.h>
>> #include "common.h"
>> @@ -63,6 +64,15 @@ void __init rcar_gen2_timer_init(void)
>> void __iomem *base;
>> u32 freq;
>> + /*
>> + * If PSCI is available then most likely we are running on
>> PSCI-enabled
>> + * U-Boot which, we assume, has already taken care of resetting
>> CNTVOFF
>> + * and updating counter module before switching to non-secure mode
>> + * and we don't need to.
>> + */
>> + if (psci_ops.cpu_on) > + goto skip_update;
> Are you sure this is working when ARM_PSCI_FW is not selected? Is it
> possible to have a .config for RCAR without ARM_PSCI_FW?
Oh, my fault. Mainline shmobile_defconfig has PSCI stuff disabled.
I should have checked for the PSCI operation to be available only if
CONFIG_ARM_PSCI_FW is defined.
Thank you for pointing this out.
>
> Cheers,
>
--
Regards,
Oleksandr Tyshchenko