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-rw-r--r--drivers/irqchip/irq-davinci-cp-intc.c260
1 files changed, 260 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-davinci-cp-intc.c b/drivers/irqchip/irq-davinci-cp-intc.c
new file mode 100644
index 000000000..7482c8ed3
--- /dev/null
+++ b/drivers/irqchip/irq-davinci-cp-intc.c
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Author: Steve Chen <schen@mvista.com>
+// Copyright (C) 2008-2009, MontaVista Software, Inc. <source@mvista.com>
+// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+// Copyright (C) 2019, Texas Instruments
+//
+// TI Common Platform Interrupt Controller (cp_intc) driver
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/irq-davinci-cp-intc.h>
+#include <linux/irqdomain.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/exception.h>
+
+#define DAVINCI_CP_INTC_CTRL 0x04
+#define DAVINCI_CP_INTC_HOST_CTRL 0x0c
+#define DAVINCI_CP_INTC_GLOBAL_ENABLE 0x10
+#define DAVINCI_CP_INTC_SYS_STAT_IDX_CLR 0x24
+#define DAVINCI_CP_INTC_SYS_ENABLE_IDX_SET 0x28
+#define DAVINCI_CP_INTC_SYS_ENABLE_IDX_CLR 0x2c
+#define DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET 0x34
+#define DAVINCI_CP_INTC_HOST_ENABLE_IDX_CLR 0x38
+#define DAVINCI_CP_INTC_PRIO_IDX 0x80
+#define DAVINCI_CP_INTC_SYS_STAT_CLR(n) (0x0280 + (n << 2))
+#define DAVINCI_CP_INTC_SYS_ENABLE_CLR(n) (0x0380 + (n << 2))
+#define DAVINCI_CP_INTC_CHAN_MAP(n) (0x0400 + (n << 2))
+#define DAVINCI_CP_INTC_SYS_POLARITY(n) (0x0d00 + (n << 2))
+#define DAVINCI_CP_INTC_SYS_TYPE(n) (0x0d80 + (n << 2))
+#define DAVINCI_CP_INTC_HOST_ENABLE(n) (0x1500 + (n << 2))
+#define DAVINCI_CP_INTC_PRI_INDX_MASK GENMASK(9, 0)
+#define DAVINCI_CP_INTC_GPIR_NONE BIT(31)
+
+static void __iomem *davinci_cp_intc_base;
+static struct irq_domain *davinci_cp_intc_irq_domain;
+
+static inline unsigned int davinci_cp_intc_read(unsigned int offset)
+{
+ return readl_relaxed(davinci_cp_intc_base + offset);
+}
+
+static inline void davinci_cp_intc_write(unsigned long value,
+ unsigned int offset)
+{
+ writel_relaxed(value, davinci_cp_intc_base + offset);
+}
+
+static void davinci_cp_intc_ack_irq(struct irq_data *d)
+{
+ davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_STAT_IDX_CLR);
+}
+
+static void davinci_cp_intc_mask_irq(struct irq_data *d)
+{
+ /* XXX don't know why we need to disable nIRQ here... */
+ davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_CLR);
+ davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_ENABLE_IDX_CLR);
+ davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET);
+}
+
+static void davinci_cp_intc_unmask_irq(struct irq_data *d)
+{
+ davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_ENABLE_IDX_SET);
+}
+
+static int davinci_cp_intc_set_irq_type(struct irq_data *d,
+ unsigned int flow_type)
+{
+ unsigned int reg, mask, polarity, type;
+
+ reg = BIT_WORD(d->hwirq);
+ mask = BIT_MASK(d->hwirq);
+ polarity = davinci_cp_intc_read(DAVINCI_CP_INTC_SYS_POLARITY(reg));
+ type = davinci_cp_intc_read(DAVINCI_CP_INTC_SYS_TYPE(reg));
+
+ switch (flow_type) {
+ case IRQ_TYPE_EDGE_RISING:
+ polarity |= mask;
+ type |= mask;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ polarity &= ~mask;
+ type |= mask;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ polarity |= mask;
+ type &= ~mask;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ polarity &= ~mask;
+ type &= ~mask;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ davinci_cp_intc_write(polarity, DAVINCI_CP_INTC_SYS_POLARITY(reg));
+ davinci_cp_intc_write(type, DAVINCI_CP_INTC_SYS_TYPE(reg));
+
+ return 0;
+}
+
+static struct irq_chip davinci_cp_intc_irq_chip = {
+ .name = "cp_intc",
+ .irq_ack = davinci_cp_intc_ack_irq,
+ .irq_mask = davinci_cp_intc_mask_irq,
+ .irq_unmask = davinci_cp_intc_unmask_irq,
+ .irq_set_type = davinci_cp_intc_set_irq_type,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static asmlinkage void __exception_irq_entry
+davinci_cp_intc_handle_irq(struct pt_regs *regs)
+{
+ int gpir, irqnr, none;
+
+ /*
+ * The interrupt number is in first ten bits. The NONE field set to 1
+ * indicates a spurious irq.
+ */
+
+ gpir = davinci_cp_intc_read(DAVINCI_CP_INTC_PRIO_IDX);
+ irqnr = gpir & DAVINCI_CP_INTC_PRI_INDX_MASK;
+ none = gpir & DAVINCI_CP_INTC_GPIR_NONE;
+
+ if (unlikely(none)) {
+ pr_err_once("%s: spurious irq!\n", __func__);
+ return;
+ }
+
+ generic_handle_domain_irq(davinci_cp_intc_irq_domain, irqnr);
+}
+
+static int davinci_cp_intc_host_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ pr_debug("cp_intc_host_map(%d, 0x%lx)\n", virq, hw);
+
+ irq_set_chip(virq, &davinci_cp_intc_irq_chip);
+ irq_set_probe(virq);
+ irq_set_handler(virq, handle_edge_irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops davinci_cp_intc_irq_domain_ops = {
+ .map = davinci_cp_intc_host_map,
+ .xlate = irq_domain_xlate_onetwocell,
+};
+
+static int __init
+davinci_cp_intc_do_init(const struct davinci_cp_intc_config *config,
+ struct device_node *node)
+{
+ unsigned int num_regs = BITS_TO_LONGS(config->num_irqs);
+ int offset, irq_base;
+ void __iomem *req;
+
+ req = request_mem_region(config->reg.start,
+ resource_size(&config->reg),
+ "davinci-cp-intc");
+ if (!req) {
+ pr_err("%s: register range busy\n", __func__);
+ return -EBUSY;
+ }
+
+ davinci_cp_intc_base = ioremap(config->reg.start,
+ resource_size(&config->reg));
+ if (!davinci_cp_intc_base) {
+ pr_err("%s: unable to ioremap register range\n", __func__);
+ return -EINVAL;
+ }
+
+ davinci_cp_intc_write(0, DAVINCI_CP_INTC_GLOBAL_ENABLE);
+
+ /* Disable all host interrupts */
+ davinci_cp_intc_write(0, DAVINCI_CP_INTC_HOST_ENABLE(0));
+
+ /* Disable system interrupts */
+ for (offset = 0; offset < num_regs; offset++)
+ davinci_cp_intc_write(~0,
+ DAVINCI_CP_INTC_SYS_ENABLE_CLR(offset));
+
+ /* Set to normal mode, no nesting, no priority hold */
+ davinci_cp_intc_write(0, DAVINCI_CP_INTC_CTRL);
+ davinci_cp_intc_write(0, DAVINCI_CP_INTC_HOST_CTRL);
+
+ /* Clear system interrupt status */
+ for (offset = 0; offset < num_regs; offset++)
+ davinci_cp_intc_write(~0,
+ DAVINCI_CP_INTC_SYS_STAT_CLR(offset));
+
+ /* Enable nIRQ (what about nFIQ?) */
+ davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET);
+
+ /* Default all priorities to channel 7. */
+ num_regs = (config->num_irqs + 3) >> 2; /* 4 channels per register */
+ for (offset = 0; offset < num_regs; offset++)
+ davinci_cp_intc_write(0x07070707,
+ DAVINCI_CP_INTC_CHAN_MAP(offset));
+
+ irq_base = irq_alloc_descs(-1, 0, config->num_irqs, 0);
+ if (irq_base < 0) {
+ pr_err("%s: unable to allocate interrupt descriptors: %d\n",
+ __func__, irq_base);
+ return irq_base;
+ }
+
+ davinci_cp_intc_irq_domain = irq_domain_add_legacy(
+ node, config->num_irqs, irq_base, 0,
+ &davinci_cp_intc_irq_domain_ops, NULL);
+
+ if (!davinci_cp_intc_irq_domain) {
+ pr_err("%s: unable to create an interrupt domain\n", __func__);
+ return -EINVAL;
+ }
+
+ set_handle_irq(davinci_cp_intc_handle_irq);
+
+ /* Enable global interrupt */
+ davinci_cp_intc_write(1, DAVINCI_CP_INTC_GLOBAL_ENABLE);
+
+ return 0;
+}
+
+int __init davinci_cp_intc_init(const struct davinci_cp_intc_config *config)
+{
+ return davinci_cp_intc_do_init(config, NULL);
+}
+
+static int __init davinci_cp_intc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct davinci_cp_intc_config config = { };
+ int ret;
+
+ ret = of_address_to_resource(node, 0, &config.reg);
+ if (ret) {
+ pr_err("%s: unable to get the register range from device-tree\n",
+ __func__);
+ return ret;
+ }
+
+ ret = of_property_read_u32(node, "ti,intc-size", &config.num_irqs);
+ if (ret) {
+ pr_err("%s: unable to read the 'ti,intc-size' property\n",
+ __func__);
+ return ret;
+ }
+
+ return davinci_cp_intc_do_init(&config, node);
+}
+IRQCHIP_DECLARE(cp_intc, "ti,cp-intc", davinci_cp_intc_of_init);