From 9968e8dbf3887c692dd7f2f83bd43678acd394a5 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 20 Apr 2024 00:03:09 +0200 Subject: ARM: dts: stm32: Ping IWDG on exit from PSCI suspend code Make sure the OS would not get any spurious IWDG pretimeout IRQ right after the system wakes up. This may happen in case the SoC got woken up by another source than the IWDG pretimeout and the pretimeout IRQ arrived immediately afterward, but too late to be handled by the suspend main loop. In case either of the IWDG is enabled, ping it first and then return to the OS. Signed-off-by: Marek Vasut Reviewed-by: Patrice Chotard Reviewed-by: Igor Opaniuk --- arch/arm/mach-stm32mp/stm32mp1/psci.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/arm/mach-stm32mp/stm32mp1/psci.c b/arch/arm/mach-stm32mp/stm32mp1/psci.c index 4f2379d..e991039 100644 --- a/arch/arm/mach-stm32mp/stm32mp1/psci.c +++ b/arch/arm/mach-stm32mp/stm32mp1/psci.c @@ -809,6 +809,27 @@ void __secure psci_system_suspend(u32 __always_unused function_id, clrbits_le32(STM32_SYSCFG_BASE + SYSCFG_CMPCR, SYSCFG_CMPCR_SW_CTRL); /* + * Make sure the OS would not get any spurious IWDG pretimeout IRQ + * right after the system wakes up. This may happen in case the SoC + * got woken up by another source than the IWDG pretimeout and the + * pretimeout IRQ arrived immediately afterward, but too late to be + * handled by the main loop above. In case either of the IWDG is + * enabled, ping it first and then return to the OS. + */ + + /* Ping IWDG1 and ACK pretimer IRQ */ + if (gic_enabled[4] & BIT(22)) { + writel(IWDG_KR_RELOAD_KEY, STM32_IWDG1_BASE + IWDG_KR); + writel(IWDG_EWCR_EWIC, STM32_IWDG1_BASE + IWDG_EWCR); + } + + /* Ping IWDG2 and ACK pretimer IRQ */ + if (gic_enabled[4] & BIT(23)) { + writel(IWDG_KR_RELOAD_KEY, STM32_IWDG2_BASE + IWDG_KR); + writel(IWDG_EWCR_EWIC, STM32_IWDG2_BASE + IWDG_EWCR); + } + + /* * 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 -- cgit v1.1