From ccd9432a5c85f35df7b491a1b701560d247466a5 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Wed, 17 Aug 2016 13:49:19 +0100 Subject: [PATCH] irqchip/gicv3: Remove disabling redistributor and group1 non-secure interrupts As per the GICv3 specification, to power down a processor using GICv3 and allow automatic power-on if an interrupt must be sent to a processor, software must set Enable to zero for all interrupt groups(by writing to GICC_CTLR or ICC_IGRPEN{0,1}_EL1/3 as appropriate. When commit 3708d52fc6bb ("irqchip: gic-v3: Implement CPU PM notifier") was introduced there were no firmware implementations(in particular PSCI) handling this. Linux kernel may not be aware of the CPU power state details and might fail to identify the power states that require quiescing the CPU interface. Even if it can be aware of those details, it can't determine which CPU power state have been triggered at the platform level and how the power control is implemented. This patch make disabling redistributor and group1 non-secure interrupts in the power down path and re-enabling of redistributor in the power-up path conditional. It will be handled in the kernel if and only if the non-secure accesses are permitted to access and modify control registers. It is left to the platform implementation otherwise. Cc: Marc Zyngier Cc: Lorenzo Pieralisi Cc: Thomas Gleixner Cc: Jason Cooper Tested-by: Christopher Covington Signed-off-by: Sudeep Holla Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 6fc56c3466b0..ede5672ab34d 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -667,13 +667,20 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, #endif #ifdef CONFIG_CPU_PM +/* Check whether it's single security state view */ +static bool gic_dist_security_disabled(void) +{ + return readl_relaxed(gic_data.dist_base + GICD_CTLR) & GICD_CTLR_DS; +} + static int gic_cpu_pm_notifier(struct notifier_block *self, unsigned long cmd, void *v) { if (cmd == CPU_PM_EXIT) { - gic_enable_redist(true); + if (gic_dist_security_disabled()) + gic_enable_redist(true); gic_cpu_sys_reg_init(); - } else if (cmd == CPU_PM_ENTER) { + } else if (cmd == CPU_PM_ENTER && gic_dist_security_disabled()) { gic_write_grpen1(0); gic_enable_redist(false); }