From 98a3308ea864afa1e42ae546ddbe5e4641f7716c Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 26 Mar 2019 15:03:59 +0100 Subject: ARM: exynos: Fix infinite loops on CPU powerup failure Add timeout to infinite loops during the CPU powerup procedures. It is better to report an error instead of busylooping for infinite time in case of failure. Signed-off-by: Marek Szyprowski Signed-off-by: Krzysztof Kozlowski --- arch/arm/mach-exynos/mcpm-exynos.c | 13 ++++++++++++- arch/arm/mach-exynos/platsmp.c | 9 ++++++++- 2 files changed, 20 insertions(+), 2 deletions(-) (limited to 'arch/arm/mach-exynos') diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c index 72bc035bedbe..9a681b421ae1 100644 --- a/arch/arm/mach-exynos/mcpm-exynos.c +++ b/arch/arm/mach-exynos/mcpm-exynos.c @@ -75,14 +75,25 @@ static int exynos_cpu_powerup(unsigned int cpu, unsigned int cluster) */ if (cluster && cluster == MPIDR_AFFINITY_LEVEL(cpu_logical_map(0), 1)) { + unsigned int timeout = 16; + /* * Before we reset the Little cores, we should wait * the SPARE2 register is set to 1 because the init * codes of the iROM will set the register after * initialization. */ - while (!pmu_raw_readl(S5P_PMU_SPARE2)) + while (timeout && !pmu_raw_readl(S5P_PMU_SPARE2)) { + timeout--; udelay(10); + } + + if (timeout == 0) { + pr_err("cpu %u cluster %u powerup failed\n", + cpu, cluster); + exynos_cpu_power_down(cpunr); + return -ETIMEDOUT; + } pmu_raw_writel(EXYNOS5420_KFC_CORE_RESET(cpu), EXYNOS_SWRESET); diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c index abcac6164233..0cbbae8bf1f8 100644 --- a/arch/arm/mach-exynos/platsmp.c +++ b/arch/arm/mach-exynos/platsmp.c @@ -214,13 +214,20 @@ static inline void __iomem *cpu_boot_reg(int cpu) */ void exynos_core_restart(u32 core_id) { + unsigned int timeout = 16; u32 val; if (!of_machine_is_compatible("samsung,exynos3250")) return; - while (!pmu_raw_readl(S5P_PMU_SPARE2)) + while (timeout && !pmu_raw_readl(S5P_PMU_SPARE2)) { + timeout--; udelay(10); + } + if (timeout == 0) { + pr_err("cpu core %u restart failed\n", core_id); + return; + } udelay(10); val = pmu_raw_readl(EXYNOS_ARM_CORE_STATUS(core_id)); -- cgit