diff --git a/arch/arm/mach-stm32mp/stm32mp1/psci.c b/arch/arm/mach-stm32mp/stm32mp1/psci.c index 8cdeb0ab3f..4f2379df45 100644 --- a/arch/arm/mach-stm32mp/stm32mp1/psci.c +++ b/arch/arm/mach-stm32mp/stm32mp1/psci.c @@ -703,6 +703,8 @@ void __secure psci_system_suspend(u32 __always_unused function_id, { u32 saved_mcudivr, saved_pll3cr, saved_pll4cr, saved_mssckselr; u32 gicd_addr = stm32mp_get_gicd_base_address(); + u32 cpu = psci_get_cpu_id(); + u32 sp = (u32)__secure_stack_end - (cpu << ARM_PSCI_STACK_SHIFT); bool iwdg1_wake = false; bool iwdg2_wake = false; bool other_wake = false; @@ -805,4 +807,16 @@ void __secure psci_system_suspend(u32 __always_unused function_id, writel(SYSCFG_CMPENR_MPUEN, STM32_SYSCFG_BASE + SYSCFG_CMPENSETR); clrbits_le32(STM32_SYSCFG_BASE + SYSCFG_CMPCR, SYSCFG_CMPCR_SW_CTRL); + + /* + * The system has resumed successfully. Rewrite LR register stored + * on stack with 'ep' value, so that on return from this PSCI call, + * the code would jump to that 'ep' resume entry point code path + * instead of the previous 'lr' register content which (e.g. with + * Linux) points to resume failure code path. + * + * See arch/arm/cpu/armv7/psci.S _smc_psci: for the stack layout + * used here, SP-4 is PC, SP-8 is LR, SP-12 is R7, and so on. + */ + writel(ep, sp - 8); }