ARM: tegra: irq: add wake up handling

Add the wake up handling for legacy irq controller, and using
IRQCHIP_MASK_ON_SUSPEND for wake irq handling.

Based on the work by:
Varun Wadekar <vwadekar@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

3 files changed, 103 insertions, 1 deletions

diff --git a/arch/arm/mach-tegra/common.c b/arch/arm/mach-tegra/common.c
index b02ebe767e7f..c84505c1f644 100644
--- a/arch/arm/mach-tegra/common.c
+++ b/arch/arm/mach-tegra/common.c
@@ -33,6 +33,7 @@
 #include "common.h"
 #include "fuse.h"
 #include "iomap.h"
+#include "irq.h"
 #include "pmc.h"
 #include "apbio.h"
 #include "sleep.h"
@@ -64,6 +65,7 @@ void __init tegra_dt_init_irq(void)
         tegra_pmc_init();
         tegra_init_irq();
         irqchip_init();
+        tegra_legacy_irq_syscore_init();
 }
 #endif
 
diff --git a/arch/arm/mach-tegra/irq.c b/arch/arm/mach-tegra/irq.c
index 1952e82797cc..0de4eed1493d 100644
--- a/arch/arm/mach-tegra/irq.c
+++ b/arch/arm/mach-tegra/irq.c
@@ -4,7 +4,7 @@
  * Author:
  *      Colin Cross <ccross@android.com>
  *
- * Copyright (C) 2010, NVIDIA Corporation
+ * Copyright (C) 2010,2013, NVIDIA Corporation
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -23,6 +23,7 @@
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/irqchip/arm-gic.h>
+#include <linux/syscore_ops.h>
 
 #include "board.h"
 #include "iomap.h"
@@ -43,6 +44,7 @@
 #define ICTLR_COP_IEP_CLASS     0x3c
 
 #define FIRST_LEGACY_IRQ 32
+#define TEGRA_MAX_NUM_ICTLRS    5
 
 #define SGI_MASK 0xFFFF
 
@@ -56,6 +58,15 @@ static void __iomem *ictlr_reg_base[] = {
         IO_ADDRESS(TEGRA_QUINARY_ICTLR_BASE),
 };
 
+#ifdef CONFIG_PM_SLEEP
+static u32 cop_ier[TEGRA_MAX_NUM_ICTLRS];
+static u32 cop_iep[TEGRA_MAX_NUM_ICTLRS];
+static u32 cpu_ier[TEGRA_MAX_NUM_ICTLRS];
+static u32 cpu_iep[TEGRA_MAX_NUM_ICTLRS];
+
+static u32 ictlr_wake_mask[TEGRA_MAX_NUM_ICTLRS];
+#endif
+
 bool tegra_pending_sgi(void)
 {
         u32 pending_set;
@@ -125,6 +136,87 @@ static int tegra_retrigger(struct irq_data *d)
         return 1;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int tegra_set_wake(struct irq_data *d, unsigned int enable)
+{
+        u32 irq = d->irq;
+        u32 index, mask;
+
+        if (irq < FIRST_LEGACY_IRQ ||
+                irq >= FIRST_LEGACY_IRQ + num_ictlrs * 32)
+                return -EINVAL;
+
+        index = ((irq - FIRST_LEGACY_IRQ) / 32);
+        mask = BIT((irq - FIRST_LEGACY_IRQ) % 32);
+        if (enable)
+                ictlr_wake_mask[index] |= mask;
+        else
+                ictlr_wake_mask[index] &= ~mask;
+
+        return 0;
+}
+
+static int tegra_legacy_irq_suspend(void)
+{
+        unsigned long flags;
+        int i;
+
+        local_irq_save(flags);
+        for (i = 0; i < num_ictlrs; i++) {
+                void __iomem *ictlr = ictlr_reg_base[i];
+                /* Save interrupt state */
+                cpu_ier[i] = readl_relaxed(ictlr + ICTLR_CPU_IER);
+                cpu_iep[i] = readl_relaxed(ictlr + ICTLR_CPU_IEP_CLASS);
+                cop_ier[i] = readl_relaxed(ictlr + ICTLR_COP_IER);
+                cop_iep[i] = readl_relaxed(ictlr + ICTLR_COP_IEP_CLASS);
+
+                /* Disable COP interrupts */
+                writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
+
+                /* Disable CPU interrupts */
+                writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
+
+                /* Enable the wakeup sources of ictlr */
+                writel_relaxed(ictlr_wake_mask[i], ictlr + ICTLR_CPU_IER_SET);
+        }
+        local_irq_restore(flags);
+
+        return 0;
+}
+
+static void tegra_legacy_irq_resume(void)
+{
+        unsigned long flags;
+        int i;
+
+        local_irq_save(flags);
+        for (i = 0; i < num_ictlrs; i++) {
+                void __iomem *ictlr = ictlr_reg_base[i];
+                writel_relaxed(cpu_iep[i], ictlr + ICTLR_CPU_IEP_CLASS);
+                writel_relaxed(~0ul, ictlr + ICTLR_CPU_IER_CLR);
+                writel_relaxed(cpu_ier[i], ictlr + ICTLR_CPU_IER_SET);
+                writel_relaxed(cop_iep[i], ictlr + ICTLR_COP_IEP_CLASS);
+                writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
+                writel_relaxed(cop_ier[i], ictlr + ICTLR_COP_IER_SET);
+        }
+        local_irq_restore(flags);
+}
+
+static struct syscore_ops tegra_legacy_irq_syscore_ops = {
+        .suspend = tegra_legacy_irq_suspend,
+        .resume = tegra_legacy_irq_resume,
+};
+
+int tegra_legacy_irq_syscore_init(void)
+{
+        register_syscore_ops(&tegra_legacy_irq_syscore_ops);
+
+        return 0;
+}
+#else
+#define tegra_set_wake NULL
+#endif
+
 void __init tegra_init_irq(void)
 {
         int i;
@@ -150,6 +242,8 @@ void __init tegra_init_irq(void)
         gic_arch_extn.irq_mask = tegra_mask;
         gic_arch_extn.irq_unmask = tegra_unmask;
         gic_arch_extn.irq_retrigger = tegra_retrigger;
+        gic_arch_extn.irq_set_wake = tegra_set_wake;
+        gic_arch_extn.flags = IRQCHIP_MASK_ON_SUSPEND;
 
         /*
          * Check if there is a devicetree present, since the GIC will be
diff --git a/arch/arm/mach-tegra/irq.h b/arch/arm/mach-tegra/irq.h
index 5142649bba05..bc05ce5613fb 100644
--- a/arch/arm/mach-tegra/irq.h
+++ b/arch/arm/mach-tegra/irq.h
@@ -19,4 +19,10 @@
 
 bool tegra_pending_sgi(void);
 
+#ifdef CONFIG_PM_SLEEP
+int tegra_legacy_irq_syscore_init(void);
+#else
+static inline int tegra_legacy_irq_syscore_init(void) { return 0; }
+#endif
+
 #endif