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authorJoseph Lo <josephl@nvidia.com>2013-01-16 02:10:26 +0400
committerStephen Warren <swarren@nvidia.com>2013-01-28 22:20:38 +0400
commitd4b92fb2535a5b35cab9713d6793f1674cc45ba7 (patch)
tree27b06e1830364115924e430a4dbfcd339d681061 /arch
parent9304512151b0933c454f0842cdb19bec23422bc5 (diff)
downloadlinux-d4b92fb2535a5b35cab9713d6793f1674cc45ba7.tar.xz
ARM: tegra: add pending SGI checking API
The "powered-down" CPU idle mode of Tegra cut off the vdd_cpu rail, it include the power of GIC. That caused the SGI (Software Generated Interrupt) been lost. Because the SGI can't wake up the CPU that in the "powered-down" CPU idle mode. We need to check if there is any pending SGI when go into "powered-down" CPU idle mode. This is important especially when applying the coupled cpuidle framework into "power-down" cpuidle dirver. Because the coupled cpuidle framework may have the chance that misses IPI_SINGLE_FUNC handling sometimes. For the PPI or SPI, something like the legacy peripheral interrupt. It still can be maintained by Tegra legacy interrupt controller. If there is any pending PPI or SPI when CPU in "powered-down" CPU idle mode. The CPU can be woken up immediately. So we don't need to take care the same situation for PPI or SPI. Signed-off-by: Joseph Lo <josephl@nvidia.com> Signed-off-by: Stephen Warren <swarren@nvidia.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mach-tegra/irq.c15
-rw-r--r--arch/arm/mach-tegra/irq.h22
2 files changed, 37 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/irq.c b/arch/arm/mach-tegra/irq.c
index b7886f183511..c9976e337bb9 100644
--- a/arch/arm/mach-tegra/irq.c
+++ b/arch/arm/mach-tegra/irq.c
@@ -45,6 +45,8 @@
#define FIRST_LEGACY_IRQ 32
+#define SGI_MASK 0xFFFF
+
static int num_ictlrs;
static void __iomem *ictlr_reg_base[] = {
@@ -55,6 +57,19 @@ static void __iomem *ictlr_reg_base[] = {
IO_ADDRESS(TEGRA_QUINARY_ICTLR_BASE),
};
+bool tegra_pending_sgi(void)
+{
+ u32 pending_set;
+ void __iomem *distbase = IO_ADDRESS(TEGRA_ARM_INT_DIST_BASE);
+
+ pending_set = readl_relaxed(distbase + GIC_DIST_PENDING_SET);
+
+ if (pending_set & SGI_MASK)
+ return true;
+
+ return false;
+}
+
static inline void tegra_irq_write_mask(unsigned int irq, unsigned long reg)
{
void __iomem *base;
diff --git a/arch/arm/mach-tegra/irq.h b/arch/arm/mach-tegra/irq.h
new file mode 100644
index 000000000000..5142649bba05
--- /dev/null
+++ b/arch/arm/mach-tegra/irq.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2012, NVIDIA Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __TEGRA_IRQ_H
+#define __TEGRA_IRQ_H
+
+bool tegra_pending_sgi(void);
+
+#endif