Messages in this thread Patch in this message | | | From | Sudeep Holla <> | Subject | [PATCH v2] irqchip/gicv3: remove disabling redistributor and group1 non-secure interrupts | Date | Wed, 17 Aug 2016 13:49:19 +0100 |
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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 <marc.zyngier@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Tested-by: Christopher Covington <cov@codeaurora.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> --- drivers/irqchip/irq-gic-v3.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
v1->v2: - Moved gic_dist_security_disabled inside CONFIG_CPU_PM to fix the build warning triggered otherwise.
Hi Marc,
Consider this as a fix for v4.8 as it fixes CPUIdle related boot hang on Qualcomm QDF2432 platform.
Regards, Sudeep
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); } -- 2.7.4
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