leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

arm: psci: save context id for cpu_on PSCI command

Browse Source 
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>
This commit is contained in:
Patrick Delaunay 2018-04-16 10:13:22 +02:00 committed by Tom Rini
parent 890e79f2b1
commit 1a047c23f9
3 changed files with 21 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
arch/arm/cpu/armv7/psci-common.c
View File

@ -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 @@ u32 __secure psci_get_target_pc(int cpu)
return psci_target_pc[cpu];
}
u32 __secure psci_get_context_id(int cpu)
{
return psci_context_id[cpu];
}

4
arch/arm/cpu/armv7/psci.S
View File

@ -327,6 +327,10 @@ ENTRY(psci_cpu_entry)
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)

4
arch/arm/include/asm/psci.h
View File

@ -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);