3 files changed, 505 insertions, 0 deletions

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 1fea003ed33f..3792a1aa52b8 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -30,6 +30,11 @@ config ARM_VIC_NR
           The maximum number of VICs available in the system, for
           power management.
 
+config IMGPDC_IRQ
+        bool
+        select GENERIC_IRQ_CHIP
+        select IRQ_DOMAIN
+
 config ORION_IRQCHIP
         bool
         select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index e65c41a7366b..81e8cd49ae76 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_SPEAR3XX)		+= spear-shirq.o
 obj-$(CONFIG_ARM_GIC)                   += irq-gic.o
 obj-$(CONFIG_ARM_NVIC)                  += irq-nvic.o
 obj-$(CONFIG_ARM_VIC)                   += irq-vic.o
+obj-$(CONFIG_IMGPDC_IRQ)                += irq-imgpdc.o
 obj-$(CONFIG_SIRF_IRQ)                  += irq-sirfsoc.o
 obj-$(CONFIG_RENESAS_INTC_IRQPIN)       += irq-renesas-intc-irqpin.o
 obj-$(CONFIG_RENESAS_IRQC)              += irq-renesas-irqc.o
diff --git a/drivers/irqchip/irq-imgpdc.c b/drivers/irqchip/irq-imgpdc.c
new file mode 100644
index 000000000000..8071c2eb0248
--- /dev/null
+++ b/drivers/irqchip/irq-imgpdc.c
@@ -0,0 +1,499 @@
+/*
+ * IMG PowerDown Controller (PDC)
+ *
+ * Copyright 2010-2013 Imagination Technologies Ltd.
+ *
+ * Exposes the syswake and PDC peripheral wake interrupts to the system.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+/* PDC interrupt register numbers */
+
+#define PDC_IRQ_STATUS                  0x310
+#define PDC_IRQ_ENABLE                  0x314
+#define PDC_IRQ_CLEAR                   0x318
+#define PDC_IRQ_ROUTE                   0x31c
+#define PDC_SYS_WAKE_BASE               0x330
+#define PDC_SYS_WAKE_STRIDE             0x8
+#define PDC_SYS_WAKE_CONFIG_BASE        0x334
+#define PDC_SYS_WAKE_CONFIG_STRIDE      0x8
+
+/* PDC interrupt register field masks */
+
+#define PDC_IRQ_SYS3                    0x08
+#define PDC_IRQ_SYS2                    0x04
+#define PDC_IRQ_SYS1                    0x02
+#define PDC_IRQ_SYS0                    0x01
+#define PDC_IRQ_ROUTE_WU_EN_SYS3        0x08000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS2        0x04000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS1        0x02000000
+#define PDC_IRQ_ROUTE_WU_EN_SYS0        0x01000000
+#define PDC_IRQ_ROUTE_WU_EN_WD          0x00040000
+#define PDC_IRQ_ROUTE_WU_EN_IR          0x00020000
+#define PDC_IRQ_ROUTE_WU_EN_RTC         0x00010000
+#define PDC_IRQ_ROUTE_EXT_EN_SYS3       0x00000800
+#define PDC_IRQ_ROUTE_EXT_EN_SYS2       0x00000400
+#define PDC_IRQ_ROUTE_EXT_EN_SYS1       0x00000200
+#define PDC_IRQ_ROUTE_EXT_EN_SYS0       0x00000100
+#define PDC_IRQ_ROUTE_EXT_EN_WD         0x00000004
+#define PDC_IRQ_ROUTE_EXT_EN_IR         0x00000002
+#define PDC_IRQ_ROUTE_EXT_EN_RTC        0x00000001
+#define PDC_SYS_WAKE_RESET              0x00000010
+#define PDC_SYS_WAKE_INT_MODE           0x0000000e
+#define PDC_SYS_WAKE_INT_MODE_SHIFT     1
+#define PDC_SYS_WAKE_PIN_VAL            0x00000001
+
+/* PDC interrupt constants */
+
+#define PDC_SYS_WAKE_INT_LOW            0x0
+#define PDC_SYS_WAKE_INT_HIGH           0x1
+#define PDC_SYS_WAKE_INT_DOWN           0x2
+#define PDC_SYS_WAKE_INT_UP             0x3
+#define PDC_SYS_WAKE_INT_CHANGE         0x6
+#define PDC_SYS_WAKE_INT_NONE           0x4
+
+/**
+ * struct pdc_intc_priv - private pdc interrupt data.
+ * @nr_perips:          Number of peripheral interrupt signals.
+ * @nr_syswakes:        Number of syswake signals.
+ * @perip_irqs:         List of peripheral IRQ numbers handled.
+ * @syswake_irq:        Shared PDC syswake IRQ number.
+ * @domain:             IRQ domain for PDC peripheral and syswake IRQs.
+ * @pdc_base:           Base of PDC registers.
+ * @irq_route:          Cached version of PDC_IRQ_ROUTE register.
+ * @lock:               Lock to protect the PDC syswake registers and the cached
+ *                      values of those registers in this struct.
+ */
+struct pdc_intc_priv {
+        unsigned int            nr_perips;
+        unsigned int            nr_syswakes;
+        unsigned int            *perip_irqs;
+        unsigned int            syswake_irq;
+        struct irq_domain       *domain;
+        void __iomem            *pdc_base;
+
+        u32                     irq_route;
+        raw_spinlock_t          lock;
+};
+
+static void pdc_write(struct pdc_intc_priv *priv, unsigned int reg_offs,
+                      unsigned int data)
+{
+        iowrite32(data, priv->pdc_base + reg_offs);
+}
+
+static unsigned int pdc_read(struct pdc_intc_priv *priv,
+                             unsigned int reg_offs)
+{
+        return ioread32(priv->pdc_base + reg_offs);
+}
+
+/* Generic IRQ callbacks */
+
+#define SYS0_HWIRQ      8
+
+static unsigned int hwirq_is_syswake(irq_hw_number_t hw)
+{
+        return hw >= SYS0_HWIRQ;
+}
+
+static unsigned int hwirq_to_syswake(irq_hw_number_t hw)
+{
+        return hw - SYS0_HWIRQ;
+}
+
+static irq_hw_number_t syswake_to_hwirq(unsigned int syswake)
+{
+        return SYS0_HWIRQ + syswake;
+}
+
+static struct pdc_intc_priv *irqd_to_priv(struct irq_data *data)
+{
+        return (struct pdc_intc_priv *)data->domain->host_data;
+}
+
+/*
+ * perip_irq_mask() and perip_irq_unmask() use IRQ_ROUTE which also contains
+ * wake bits, therefore we cannot use the generic irqchip mask callbacks as they
+ * cache the mask.
+ */
+
+static void perip_irq_mask(struct irq_data *data)
+{
+        struct pdc_intc_priv *priv = irqd_to_priv(data);
+
+        raw_spin_lock(&priv->lock);
+        priv->irq_route &= ~data->mask;
+        pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+        raw_spin_unlock(&priv->lock);
+}
+
+static void perip_irq_unmask(struct irq_data *data)
+{
+        struct pdc_intc_priv *priv = irqd_to_priv(data);
+
+        raw_spin_lock(&priv->lock);
+        priv->irq_route |= data->mask;
+        pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+        raw_spin_unlock(&priv->lock);
+}
+
+static int syswake_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+        struct pdc_intc_priv *priv = irqd_to_priv(data);
+        unsigned int syswake = hwirq_to_syswake(data->hwirq);
+        unsigned int irq_mode;
+        unsigned int soc_sys_wake_regoff, soc_sys_wake;
+
+        /* translate to syswake IRQ mode */
+        switch (flow_type) {
+        case IRQ_TYPE_EDGE_BOTH:
+                irq_mode = PDC_SYS_WAKE_INT_CHANGE;
+                break;
+        case IRQ_TYPE_EDGE_RISING:
+                irq_mode = PDC_SYS_WAKE_INT_UP;
+                break;
+        case IRQ_TYPE_EDGE_FALLING:
+                irq_mode = PDC_SYS_WAKE_INT_DOWN;
+                break;
+        case IRQ_TYPE_LEVEL_HIGH:
+                irq_mode = PDC_SYS_WAKE_INT_HIGH;
+                break;
+        case IRQ_TYPE_LEVEL_LOW:
+                irq_mode = PDC_SYS_WAKE_INT_LOW;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        raw_spin_lock(&priv->lock);
+
+        /* set the IRQ mode */
+        soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + syswake*PDC_SYS_WAKE_STRIDE;
+        soc_sys_wake = pdc_read(priv, soc_sys_wake_regoff);
+        soc_sys_wake &= ~PDC_SYS_WAKE_INT_MODE;
+        soc_sys_wake |= irq_mode << PDC_SYS_WAKE_INT_MODE_SHIFT;
+        pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
+
+        /* and update the handler */
+        irq_setup_alt_chip(data, flow_type);
+
+        raw_spin_unlock(&priv->lock);
+
+        return 0;
+}
+
+/* applies to both peripheral and syswake interrupts */
+static int pdc_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+        struct pdc_intc_priv *priv = irqd_to_priv(data);
+        irq_hw_number_t hw = data->hwirq;
+        unsigned int mask = (1 << 16) << hw;
+        unsigned int dst_irq;
+
+        raw_spin_lock(&priv->lock);
+        if (on)
+                priv->irq_route |= mask;
+        else
+                priv->irq_route &= ~mask;
+        pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+        raw_spin_unlock(&priv->lock);
+
+        /* control the destination IRQ wakeup too for standby mode */
+        if (hwirq_is_syswake(hw))
+                dst_irq = priv->syswake_irq;
+        else
+                dst_irq = priv->perip_irqs[hw];
+        irq_set_irq_wake(dst_irq, on);
+
+        return 0;
+}
+
+static void pdc_intc_perip_isr(unsigned int irq, struct irq_desc *desc)
+{
+        struct pdc_intc_priv *priv;
+        unsigned int i, irq_no;
+
+        priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
+
+        /* find the peripheral number */
+        for (i = 0; i < priv->nr_perips; ++i)
+                if (irq == priv->perip_irqs[i])
+                        goto found;
+
+        /* should never get here */
+        return;
+found:
+
+        /* pass on the interrupt */
+        irq_no = irq_linear_revmap(priv->domain, i);
+        generic_handle_irq(irq_no);
+}
+
+static void pdc_intc_syswake_isr(unsigned int irq, struct irq_desc *desc)
+{
+        struct pdc_intc_priv *priv;
+        unsigned int syswake, irq_no;
+        unsigned int status;
+
+        priv = (struct pdc_intc_priv *)irq_desc_get_handler_data(desc);
+
+        status = pdc_read(priv, PDC_IRQ_STATUS) &
+                 pdc_read(priv, PDC_IRQ_ENABLE);
+        status &= (1 << priv->nr_syswakes) - 1;
+
+        for (syswake = 0; status; status >>= 1, ++syswake) {
+                /* Has this sys_wake triggered? */
+                if (!(status & 1))
+                        continue;
+
+                irq_no = irq_linear_revmap(priv->domain,
+                                           syswake_to_hwirq(syswake));
+                generic_handle_irq(irq_no);
+        }
+}
+
+static void pdc_intc_setup(struct pdc_intc_priv *priv)
+{
+        int i;
+        unsigned int soc_sys_wake_regoff;
+        unsigned int soc_sys_wake;
+
+        /*
+         * Mask all syswake interrupts before routing, or we could receive an
+         * interrupt before we're ready to handle it.
+         */
+        pdc_write(priv, PDC_IRQ_ENABLE, 0);
+
+        /*
+         * Enable routing of all syswakes
+         * Disable all wake sources
+         */
+        priv->irq_route = ((PDC_IRQ_ROUTE_EXT_EN_SYS0 << priv->nr_syswakes) -
+                                PDC_IRQ_ROUTE_EXT_EN_SYS0);
+        pdc_write(priv, PDC_IRQ_ROUTE, priv->irq_route);
+
+        /* Initialise syswake IRQ */
+        for (i = 0; i < priv->nr_syswakes; ++i) {
+                /* set the IRQ mode to none */
+                soc_sys_wake_regoff = PDC_SYS_WAKE_BASE + i*PDC_SYS_WAKE_STRIDE;
+                soc_sys_wake = PDC_SYS_WAKE_INT_NONE
+                                << PDC_SYS_WAKE_INT_MODE_SHIFT;
+                pdc_write(priv, soc_sys_wake_regoff, soc_sys_wake);
+        }
+}
+
+static int pdc_intc_probe(struct platform_device *pdev)
+{
+        struct pdc_intc_priv *priv;
+        struct device_node *node = pdev->dev.of_node;
+        struct resource *res_regs;
+        struct irq_chip_generic *gc;
+        unsigned int i;
+        int irq, ret;
+        u32 val;
+
+        if (!node)
+                return -ENOENT;
+
+        /* Get registers */
+        res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (res_regs == NULL) {
+                dev_err(&pdev->dev, "cannot find registers resource\n");
+                return -ENOENT;
+        }
+
+        /* Allocate driver data */
+        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv) {
+                dev_err(&pdev->dev, "cannot allocate device data\n");
+                return -ENOMEM;
+        }
+        raw_spin_lock_init(&priv->lock);
+        platform_set_drvdata(pdev, priv);
+
+        /* Ioremap the registers */
+        priv->pdc_base = devm_ioremap(&pdev->dev, res_regs->start,
+                                      res_regs->end - res_regs->start);
+        if (!priv->pdc_base)
+                return -EIO;
+
+        /* Get number of peripherals */
+        ret = of_property_read_u32(node, "num-perips", &val);
+        if (ret) {
+                dev_err(&pdev->dev, "No num-perips node property found\n");
+                return -EINVAL;
+        }
+        if (val > SYS0_HWIRQ) {
+                dev_err(&pdev->dev, "num-perips (%u) out of range\n", val);
+                return -EINVAL;
+        }
+        priv->nr_perips = val;
+
+        /* Get number of syswakes */
+        ret = of_property_read_u32(node, "num-syswakes", &val);
+        if (ret) {
+                dev_err(&pdev->dev, "No num-syswakes node property found\n");
+                return -EINVAL;
+        }
+        if (val > SYS0_HWIRQ) {
+                dev_err(&pdev->dev, "num-syswakes (%u) out of range\n", val);
+                return -EINVAL;
+        }
+        priv->nr_syswakes = val;
+
+        /* Get peripheral IRQ numbers */
+        priv->perip_irqs = devm_kzalloc(&pdev->dev, 4 * priv->nr_perips,
+                                        GFP_KERNEL);
+        if (!priv->perip_irqs) {
+                dev_err(&pdev->dev, "cannot allocate perip IRQ list\n");
+                return -ENOMEM;
+        }
+        for (i = 0; i < priv->nr_perips; ++i) {
+                irq = platform_get_irq(pdev, 1 + i);
+                if (irq < 0) {
+                        dev_err(&pdev->dev, "cannot find perip IRQ #%u\n", i);
+                        return irq;
+                }
+                priv->perip_irqs[i] = irq;
+        }
+        /* check if too many were provided */
+        if (platform_get_irq(pdev, 1 + i) >= 0) {
+                dev_err(&pdev->dev, "surplus perip IRQs detected\n");
+                return -EINVAL;
+        }
+
+        /* Get syswake IRQ number */
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0) {
+                dev_err(&pdev->dev, "cannot find syswake IRQ\n");
+                return irq;
+        }
+        priv->syswake_irq = irq;
+
+        /* Set up an IRQ domain */
+        priv->domain = irq_domain_add_linear(node, 16, &irq_generic_chip_ops,
+                                             priv);
+        if (unlikely(!priv->domain)) {
+                dev_err(&pdev->dev, "cannot add IRQ domain\n");
+                return -ENOMEM;
+        }
+
+        /*
+         * Set up 2 generic irq chips with 2 chip types.
+         * The first one for peripheral irqs (only 1 chip type used)
+         * The second one for syswake irqs (edge and level chip types)
+         */
+        ret = irq_alloc_domain_generic_chips(priv->domain, 8, 2, "pdc",
+                                             handle_level_irq, 0, 0,
+                                             IRQ_GC_INIT_NESTED_LOCK);
+        if (ret)
+                goto err_generic;
+
+        /* peripheral interrupt chip */
+
+        gc = irq_get_domain_generic_chip(priv->domain, 0);
+        gc->unused      = ~(BIT(priv->nr_perips) - 1);
+        gc->reg_base    = priv->pdc_base;
+        /*
+         * IRQ_ROUTE contains wake bits, so we can't use the generic versions as
+         * they cache the mask
+         */
+        gc->chip_types[0].regs.mask             = PDC_IRQ_ROUTE;
+        gc->chip_types[0].chip.irq_mask         = perip_irq_mask;
+        gc->chip_types[0].chip.irq_unmask       = perip_irq_unmask;
+        gc->chip_types[0].chip.irq_set_wake     = pdc_irq_set_wake;
+
+        /* syswake interrupt chip */
+
+        gc = irq_get_domain_generic_chip(priv->domain, 8);
+        gc->unused      = ~(BIT(priv->nr_syswakes) - 1);
+        gc->reg_base    = priv->pdc_base;
+
+        /* edge interrupts */
+        gc->chip_types[0].type                  = IRQ_TYPE_EDGE_BOTH;
+        gc->chip_types[0].handler               = handle_edge_irq;
+        gc->chip_types[0].regs.ack              = PDC_IRQ_CLEAR;
+        gc->chip_types[0].regs.mask             = PDC_IRQ_ENABLE;
+        gc->chip_types[0].chip.irq_ack          = irq_gc_ack_set_bit;
+        gc->chip_types[0].chip.irq_mask         = irq_gc_mask_clr_bit;
+        gc->chip_types[0].chip.irq_unmask       = irq_gc_mask_set_bit;
+        gc->chip_types[0].chip.irq_set_type     = syswake_irq_set_type;
+        gc->chip_types[0].chip.irq_set_wake     = pdc_irq_set_wake;
+        /* for standby we pass on to the shared syswake IRQ */
+        gc->chip_types[0].chip.flags            = IRQCHIP_MASK_ON_SUSPEND;
+
+        /* level interrupts */
+        gc->chip_types[1].type                  = IRQ_TYPE_LEVEL_MASK;
+        gc->chip_types[1].handler               = handle_level_irq;
+        gc->chip_types[1].regs.ack              = PDC_IRQ_CLEAR;
+        gc->chip_types[1].regs.mask             = PDC_IRQ_ENABLE;
+        gc->chip_types[1].chip.irq_ack          = irq_gc_ack_set_bit;
+        gc->chip_types[1].chip.irq_mask         = irq_gc_mask_clr_bit;
+        gc->chip_types[1].chip.irq_unmask       = irq_gc_mask_set_bit;
+        gc->chip_types[1].chip.irq_set_type     = syswake_irq_set_type;
+        gc->chip_types[1].chip.irq_set_wake     = pdc_irq_set_wake;
+        /* for standby we pass on to the shared syswake IRQ */
+        gc->chip_types[1].chip.flags            = IRQCHIP_MASK_ON_SUSPEND;
+
+        /* Set up the hardware to enable interrupt routing */
+        pdc_intc_setup(priv);
+
+        /* Setup chained handlers for the peripheral IRQs */
+        for (i = 0; i < priv->nr_perips; ++i) {
+                irq = priv->perip_irqs[i];
+                irq_set_handler_data(irq, priv);
+                irq_set_chained_handler(irq, pdc_intc_perip_isr);
+        }
+
+        /* Setup chained handler for the syswake IRQ */
+        irq_set_handler_data(priv->syswake_irq, priv);
+        irq_set_chained_handler(priv->syswake_irq, pdc_intc_syswake_isr);
+
+        dev_info(&pdev->dev,
+                 "PDC IRQ controller initialised (%u perip IRQs, %u syswake IRQs)\n",
+                 priv->nr_perips,
+                 priv->nr_syswakes);
+
+        return 0;
+err_generic:
+        irq_domain_remove(priv->domain);
+        return ret;
+}
+
+static int pdc_intc_remove(struct platform_device *pdev)
+{
+        struct pdc_intc_priv *priv = platform_get_drvdata(pdev);
+
+        irq_domain_remove(priv->domain);
+        return 0;
+}
+
+static const struct of_device_id pdc_intc_match[] = {
+        { .compatible = "img,pdc-intc" },
+        {}
+};
+
+static struct platform_driver pdc_intc_driver = {
+        .driver = {
+                .name           = "pdc-intc",
+                .of_match_table = pdc_intc_match,
+        },
+        .probe = pdc_intc_probe,
+        .remove = pdc_intc_remove,
+};
+
+static int __init pdc_intc_init(void)
+{
+        return platform_driver_register(&pdc_intc_driver);
+}
+core_initcall(pdc_intc_init);