--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com>
+ * Loongson Local IO Interrupt Controller support
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/irqchip.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/smp.h>
+#include <linux/irqchip/chained_irq.h>
+
+#include <boot_param.h>
+
+#define LIOINTC_CHIP_IRQ 32
+#define LIOINTC_NUM_PARENT 4
+
+#define LIOINTC_INTC_CHIP_START 0x20
+
+#define LIOINTC_REG_INTC_STATUS (LIOINTC_INTC_CHIP_START + 0x20)
+#define LIOINTC_REG_INTC_EN_STATUS (LIOINTC_INTC_CHIP_START + 0x04)
+#define LIOINTC_REG_INTC_ENABLE (LIOINTC_INTC_CHIP_START + 0x08)
+#define LIOINTC_REG_INTC_DISABLE (LIOINTC_INTC_CHIP_START + 0x0c)
+#define LIOINTC_REG_INTC_POL (LIOINTC_INTC_CHIP_START + 0x10)
+#define LIOINTC_REG_INTC_EDGE (LIOINTC_INTC_CHIP_START + 0x14)
+
+#define LIOINTC_SHIFT_INTx 4
+
+struct liointc_handler_data {
+ struct liointc_priv *priv;
+ u32 parent_int_map;
+};
+
+struct liointc_priv {
+ struct irq_chip_generic *gc;
+ struct liointc_handler_data handler[LIOINTC_NUM_PARENT];
+ u8 map_cache[LIOINTC_CHIP_IRQ];
+};
+
+static void liointc_chained_handle_irq(struct irq_desc *desc)
+{
+ struct liointc_handler_data *handler = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct irq_chip_generic *gc = handler->priv->gc;
+ u32 pending;
+
+ chained_irq_enter(chip, desc);
+
+ pending = readl(gc->reg_base + LIOINTC_REG_INTC_STATUS);
+
+ if (!pending)
+ spurious_interrupt();
+
+ while (pending) {
+ int bit = __ffs(pending);
+
+ generic_handle_irq(irq_find_mapping(gc->domain, bit));
+ pending &= ~BIT(bit);
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+static void liointc_set_bit(struct irq_chip_generic *gc,
+ unsigned int offset,
+ u32 mask, bool set)
+{
+ if (set)
+ writel(readl(gc->reg_base + offset) | mask,
+ gc->reg_base + offset);
+ else
+ writel(readl(gc->reg_base + offset) & ~mask,
+ gc->reg_base + offset);
+}
+
+static int liointc_set_type(struct irq_data *data, unsigned int type)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
+ u32 mask = data->mask;
+ unsigned long flags;
+
+ irq_gc_lock_irqsave(gc, flags);
+ switch (type) {
+ case IRQ_TYPE_LEVEL_HIGH:
+ liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false);
+ liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false);
+ liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false);
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true);
+ liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true);
+ liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false);
+ break;
+ default:
+ return -EINVAL;
+ }
+ irq_gc_unlock_irqrestore(gc, flags);
+
+ irqd_set_trigger_type(data, type);
+ return 0;
+}
+
+static void liointc_resume(struct irq_chip_generic *gc)
+{
+ struct liointc_priv *priv = gc->private;
+ unsigned long flags;
+ int i;
+
+ irq_gc_lock_irqsave(gc, flags);
+ /* Disable all at first */
+ writel(0xffffffff, gc->reg_base + LIOINTC_REG_INTC_DISABLE);
+ /* Revert map cache */
+ for (i = 0; i < LIOINTC_CHIP_IRQ; i++)
+ writeb(priv->map_cache[i], gc->reg_base + i);
+ /* Revert mask cache */
+ writel(~gc->mask_cache, gc->reg_base + LIOINTC_REG_INTC_ENABLE);
+ irq_gc_unlock_irqrestore(gc, flags);
+}
+
+static const char * const parent_names[] = {"int0", "int1", "int2", "int3"};
+
+int __init liointc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_chip_generic *gc;
+ struct irq_domain *domain;
+ struct irq_chip_type *ct;
+ struct liointc_priv *priv;
+ void __iomem *base;
+ u32 of_parent_int_map[LIOINTC_NUM_PARENT];
+ int parent_irq[LIOINTC_NUM_PARENT];
+ bool have_parent = FALSE;
+ int sz, i, err = 0;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ base = of_iomap(node, 0);
+ if (!base) {
+ err = -ENODEV;
+ goto out_free_priv;
+ }
+
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
+ parent_irq[i] = of_irq_get_byname(node, parent_names[i]);
+ if (parent_irq[i] > 0)
+ have_parent = TRUE;
+ }
+ if (!have_parent) {
+ err = -ENODEV;
+ goto out_iounmap;
+ }
+
+ sz = of_property_read_variable_u32_array(node,
+ "loongson,parent_int_map",
+ &of_parent_int_map[0],
+ LIOINTC_NUM_PARENT,
+ LIOINTC_NUM_PARENT);
+ if (sz < 4) {
+ pr_err("loongson-liointc: No parent_int_map\n");
+ err = -ENODEV;
+ goto out_iounmap;
+ }
+
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++)
+ priv->handler[i].parent_int_map = of_parent_int_map[i];
+
+ /* Setup IRQ domain */
+ domain = irq_domain_add_linear(node, 32,
+ &irq_generic_chip_ops, priv);
+ if (!domain) {
+ pr_err("loongson-liointc: cannot add IRQ domain\n");
+ err = -EINVAL;
+ goto out_iounmap;
+ }
+
+ err = irq_alloc_domain_generic_chips(domain, 32, 1,
+ node->full_name, handle_level_irq,
+ IRQ_NOPROBE, 0, 0);
+ if (err) {
+ pr_err("loongson-liointc: unable to register IRQ domain\n");
+ goto out_free_domain;
+ }
+
+
+ /* Disable all IRQs */
+ writel(0xffffffff, base + LIOINTC_REG_INTC_DISABLE);
+ /* Set to level triggered */
+ writel(0x0, base + LIOINTC_REG_INTC_EDGE);
+
+ /* Generate parent INT part of map cache */
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
+ u32 pending = priv->handler[i].parent_int_map;
+
+ while (pending) {
+ int bit = __ffs(pending);
+
+ priv->map_cache[bit] = BIT(i) << LIOINTC_SHIFT_INTx;
+ pending &= ~BIT(bit);
+ }
+ }
+
+ for (i = 0; i < LIOINTC_CHIP_IRQ; i++) {
+ /* Generate core part of map cache */
+ priv->map_cache[i] |= BIT(loongson_sysconf.boot_cpu_id);
+ writeb(priv->map_cache[i], base + i);
+ }
+
+ gc = irq_get_domain_generic_chip(domain, 0);
+ gc->private = priv;
+ gc->reg_base = base;
+ gc->domain = domain;
+ gc->resume = liointc_resume;
+
+ ct = gc->chip_types;
+ ct->regs.enable = LIOINTC_REG_INTC_ENABLE;
+ ct->regs.disable = LIOINTC_REG_INTC_DISABLE;
+ ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
+ ct->chip.irq_mask = irq_gc_mask_disable_reg;
+ ct->chip.irq_mask_ack = irq_gc_mask_disable_reg;
+ ct->chip.irq_set_type = liointc_set_type;
+
+ gc->mask_cache = 0xffffffff;
+ priv->gc = gc;
+
+ for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
+ if (parent_irq[i] <= 0)
+ continue;
+
+ priv->handler[i].priv = priv;
+ irq_set_chained_handler_and_data(parent_irq[i],
+ liointc_chained_handle_irq, &priv->handler[i]);
+ }
+
+ return 0;
+
+out_free_domain:
+ irq_domain_remove(domain);
+out_iounmap:
+ iounmap(base);
+out_free_priv:
+ kfree(priv);
+
+ return err;
+}
+
+IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init);
+IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init);
projects / platform / kernel / linux-starfive.git / commitdiff