From a2c225101234bcef8f40497bd50ccb5e9c1fb527 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 26 Aug 2014 16:03:34 +0100 Subject: [PATCH] irqchip: gic-v3: Refactor gic_enable_redist to support both enabling and disabling Currently gic_enable_redist configures the redistributors to never assert WakeRequest signal. However when powering down the processors with wake-up enabled(i.e suspend), we need to configure it to assert that signal. This patch extends gic_enable_redist so that the redistributor can be configure to assert WakeRequest and hold interrupts as pending. This is useful in suspending the processors. This patch also adds check to make sure GICR_WAKER is accessible when configuring it. Cc: Lorenzo Pieralisi Signed-off-by: Sudeep Holla [maz: removed reference to GICD_CTLR.DS and added read-back of GICR_WAKER to check that it is not RAZ/WI] Signed-off-by: Marc Zyngier Acked-by: Marc Zyngier Link: https://lkml.kernel.org/r/1409065415-20176-2-git-send-email-sudeep.holla@arm.com Signed-off-by: Jason Cooper --- drivers/irqchip/irq-gic-v3.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 57eaa5a0b1e3..37062ba6704b 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -155,7 +155,7 @@ static void gic_enable_sre(void) pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n"); } -static void gic_enable_redist(void) +static void gic_enable_redist(bool enable) { void __iomem *rbase; u32 count = 1000000; /* 1s! */ @@ -163,20 +163,30 @@ static void gic_enable_redist(void) rbase = gic_data_rdist_rd_base(); - /* Wake up this CPU redistributor */ val = readl_relaxed(rbase + GICR_WAKER); - val &= ~GICR_WAKER_ProcessorSleep; + if (enable) + /* Wake up this CPU redistributor */ + val &= ~GICR_WAKER_ProcessorSleep; + else + val |= GICR_WAKER_ProcessorSleep; writel_relaxed(val, rbase + GICR_WAKER); - while (readl_relaxed(rbase + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) { - count--; - if (!count) { - pr_err_ratelimited("redist didn't wake up...\n"); - return; - } + if (!enable) { /* Check that GICR_WAKER is writeable */ + val = readl_relaxed(rbase + GICR_WAKER); + if (!(val & GICR_WAKER_ProcessorSleep)) + return; /* No PM support in this redistributor */ + } + + while (count--) { + val = readl_relaxed(rbase + GICR_WAKER); + if (enable ^ (val & GICR_WAKER_ChildrenAsleep)) + break; cpu_relax(); udelay(1); }; + if (!count) + pr_err_ratelimited("redistributor failed to %s...\n", + enable ? "wakeup" : "sleep"); } /* @@ -381,7 +391,7 @@ static void gic_cpu_init(void) if (gic_populate_rdist()) return; - gic_enable_redist(); + gic_enable_redist(true); rbase = gic_data_rdist_sgi_base(); -- 2.30.2