arm: psci: save context id for cpu_on PSCI command
Save and use the 3rd parameter of PSCI CPU_ON request: context_id.
The context_id parameter is only meaningful to the caller.
U-Boot PSCI preserves a copy of the value passed in this parameter.
Following wakeup from a powerdown state, U-BOOT PSCI places
this value in R0 when it first enters the OS.
NB: this context id is not (yet?) used by Linux but it is mandatory
to be PSCI compliant.
update armv7 psci functions:
- psci_save_target_pc(): keep for backward compatibility with
current platform (only save PC and force context id to 0)
=> should be removed when all platform migrate to the new API
- psci_save(): new API to use by ARMv7 platform with PSCI,
save pc (= entry_point_address) and context_id
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/cpu/armv7/psci-common.c b/arch/arm/cpu/armv7/psci-common.c
index 8cb4107..73f986b 100644
--- a/arch/arm/cpu/armv7/psci-common.c
+++ b/arch/arm/cpu/armv7/psci-common.c
@@ -25,10 +25,19 @@
#include <linux/linkage.h>
static u32 psci_target_pc[CONFIG_ARMV7_PSCI_NR_CPUS] __secure_data = { 0 };
+static u32 psci_context_id[CONFIG_ARMV7_PSCI_NR_CPUS] __secure_data = { 0 };
void __secure psci_save_target_pc(int cpu, u32 pc)
{
psci_target_pc[cpu] = pc;
+ psci_context_id[cpu] = 0;
+ dsb();
+}
+
+void __secure psci_save(int cpu, u32 pc, u32 context_id)
+{
+ psci_target_pc[cpu] = pc;
+ psci_context_id[cpu] = context_id;
dsb();
}
@@ -37,3 +46,8 @@
return psci_target_pc[cpu];
}
+u32 __secure psci_get_context_id(int cpu)
+{
+ return psci_context_id[cpu];
+}
+
diff --git a/arch/arm/cpu/armv7/psci.S b/arch/arm/cpu/armv7/psci.S
index 95b962d..35fd955 100644
--- a/arch/arm/cpu/armv7/psci.S
+++ b/arch/arm/cpu/armv7/psci.S
@@ -327,6 +327,10 @@
bl _nonsec_init
bl psci_get_cpu_id @ CPU ID => r0
+ mov r2, r0 @ CPU ID => r2
+ bl psci_get_context_id @ context id => r0
+ mov r1, r0 @ context id => r1
+ mov r0, r2 @ CPU ID => r0
bl psci_get_target_pc @ target PC => r0
b _do_nonsec_entry
ENDPROC(psci_cpu_entry)
diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
index ac8b00d..b415241 100644
--- a/arch/arm/include/asm/psci.h
+++ b/arch/arm/include/asm/psci.h
@@ -93,9 +93,11 @@
#ifndef __ASSEMBLY__
#include <asm/types.h>
-/* These 2 helper functions assume cpu < CONFIG_ARMV7_PSCI_NR_CPUS */
+/* These 4 helper functions assume cpu < CONFIG_ARMV7_PSCI_NR_CPUS */
u32 psci_get_target_pc(int cpu);
+u32 psci_get_context_id(int cpu);
void psci_save_target_pc(int cpu, u32 pc);
+void psci_save(int cpu, u32 pc, u32 context_id);
void psci_cpu_entry(void);
u32 psci_get_cpu_id(void);