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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/irqchip/irq-imgpdc.c
Initial import
Diffstat (limited to 'drivers/irqchip/irq-imgpdc.c')
-rw-r--r--drivers/irqchip/irq-imgpdc.c499
1 files changed, 499 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-imgpdc.c b/drivers/irqchip/irq-imgpdc.c
new file mode 100644
index 000000000..8071c2eb0
--- /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);