From: Hongbo Zhang hongbo.zhang@nxp.com
For the robustness of codes, while powering on a CPU, it is better to check if the target CPU is already on or in the process of power on, if yes the power on routine shouldn't be executed further and should return with the corresponding status immediately.
Signed-off-by: Hongbo Zhang hongbo.zhang@nxp.com --- arch/arm/cpu/armv7/ls102xa/psci.S | 29 +++++++++++++++++++++++++++++ arch/arm/include/asm/psci.h | 5 +++++ 2 files changed, 34 insertions(+)
diff --git a/arch/arm/cpu/armv7/ls102xa/psci.S b/arch/arm/cpu/armv7/ls102xa/psci.S index 4540bb1..46fa68c 100644 --- a/arch/arm/cpu/armv7/ls102xa/psci.S +++ b/arch/arm/cpu/armv7/ls102xa/psci.S @@ -67,6 +67,22 @@ psci_cpu_on: beq out_psci_cpu_on mov r1, r0
+ bl psci_get_cpu_stack_top + sub r0, r0, #PSCI_CPU_STATUS_OFFSET + ldr r5, [r0] + + cmp r5, #PSCI_CPU_STATUS_ON + moveq r0, #ARM_PSCI_RET_ALREADY_ON + beq out_psci_cpu_on + + cmp r5, #PSCI_CPU_STATUS_ON_PENDING + moveq r0, #ARM_PSCI_RET_ON_PENDING + beq out_psci_cpu_on + + mov r5, #PSCI_CPU_STATUS_ON_PENDING + str r5, [r0] + dsb + bl psci_cpu_on_common
@ Get DCFG base address @@ -124,6 +140,12 @@ holdoff_release: rev r6, r6 str r6, [r4, #DCFG_CCSR_SCRATCHRW1]
+ mov r0, r1 + bl psci_get_cpu_stack_top + sub r0, r0, #PSCI_CPU_STATUS_OFFSET + mov r5, #PSCI_CPU_STATUS_ON + str r5, [r0] + isb dsb
@@ -138,6 +160,13 @@ out_psci_cpu_on: psci_cpu_off: bl psci_cpu_off_common
+ bl psci_get_cpu_id + bl psci_get_cpu_stack_top + sub r0, r0, #PSCI_CPU_STATUS_OFFSET + mov r5, #PSCI_CPU_STATUS_OFF + str r5, [r0] + dsb + 1: wfi b 1b
diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h index bedcd30..89a1ba5 100644 --- a/arch/arm/include/asm/psci.h +++ b/arch/arm/include/asm/psci.h @@ -67,6 +67,11 @@ #define PSCI_PERCPU_STACK_SIZE 0x400 #define PSCI_TARGET_PC_OFFSET (PSCI_PERCPU_STACK_SIZE - 4) #define PSCI_CONTEXT_ID_OFFSET (PSCI_PERCPU_STACK_SIZE - 8) +#define PSCI_CPU_STATUS_OFFSET (PSCI_PERCPU_STACK_SIZE - 12) + +#define PSCI_CPU_STATUS_OFF 0 +#define PSCI_CPU_STATUS_ON 1 +#define PSCI_CPU_STATUS_ON_PENDING 2
#ifndef __ASSEMBLY__ int psci_update_dt(void *fdt);