This controller appeared on Loongson-3 family of chips as the primary
package interrupt source.
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
drivers/irqchip/Kconfig | 9 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-ls3-iointc.c | 275 +++++++++++++++++++++++++++++++
3 files changed, 285 insertions(+)
create mode 100644 drivers/irqchip/irq-ls3-iointc.c
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 80e10f4e213a..8d9eac5fd4a7 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -471,6 +471,15 @@ config TI_SCI_INTA_IRQCHIP
If you wish to use interrupt aggregator irq resources managed by the
TI System Controller, say Y here. Otherwise, say N.
+config LS3_IOINTC
+ bool "Loongson3 I/O Interrupt Controller"
+ depends on MACH_LOONGSON64
+ default y
+ select IRQ_DOMAIN
+ select GENERIC_IRQ_CHIP
+ help
+ Support for the Loongson-3 I/O Interrupt Controller.
+
endmenu
config SIFIVE_PLIC
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 8d0fcec6ab23..49ecb8d38138 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -102,3 +102,4 @@ obj-$(CONFIG_MADERA_IRQ) += irq-madera.o
obj-$(CONFIG_LS1X_IRQ) += irq-ls1x.o
obj-$(CONFIG_TI_SCI_INTR_IRQCHIP) += irq-ti-sci-intr.o
obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.o
+obj-$(CONFIG_LS3_IOINTC) += irq-ls3-iointc.o
diff --git a/drivers/irqchip/irq-ls3-iointc.c b/drivers/irqchip/irq-ls3-iointc.c
new file mode 100644
index 000000000000..0fbff7afa43c
--- /dev/null
+++ b/drivers/irqchip/irq-ls3-iointc.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019, Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
+ * Loongson-3 IOINTC IRQ 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>
+
+
+#define LS3_CHIP_IRQ 32
+
+#define LS3_REG_INTx_MAP(x) (x * 0x1)
+#define LS3_INTC_CHIP_START 0x20
+
+#define LS3_REG_INTC_STATUS (LS3_INTC_CHIP_START + 0x00)
+#define LS3_REG_INTC_EN_STATUS (LS3_INTC_CHIP_START + 0x04)
+#define LS3_REG_INTC_ENABLE (LS3_INTC_CHIP_START + 0x08)
+#define LS3_REG_INTC_DISABLE (LS3_INTC_CHIP_START + 0x0c)
+#define LS3_REG_INTC_POL (LS3_INTC_CHIP_START + 0x10)
+#define LS3_REG_INTC_EDGE (LS3_INTC_CHIP_START + 0x18)
+
+#define LS3_MAP_CORE_INT(x, y) (u8)(BIT(x) | (BIT(y) << 4))
+
+struct ls3_iointc_priv {
+ u8 map_cache[LS3_CHIP_IRQ];
+};
+
+
+static void ls3_io_chained_handle_irq(struct irq_desc *desc)
+{
+ struct irq_chip_generic *gc = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 pending;
+
+ chained_irq_enter(chip, desc);
+
+ /* Check with mask_cache to prevent HW fake interrupt */
+ pending = ~gc->mask_cache &
+ readl(gc->reg_base + LS3_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 ls_intc_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 ls_intc_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:
+ ls_intc_set_bit(gc, LS3_REG_INTC_EDGE, mask, false);
+ ls_intc_set_bit(gc, LS3_REG_INTC_POL, mask, true);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ ls_intc_set_bit(gc, LS3_REG_INTC_EDGE, mask, false);
+ ls_intc_set_bit(gc, LS3_REG_INTC_POL, mask, false);
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ ls_intc_set_bit(gc, LS3_REG_INTC_EDGE, mask, true);
+ ls_intc_set_bit(gc, LS3_REG_INTC_POL, mask, true);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ ls_intc_set_bit(gc, LS3_REG_INTC_EDGE, mask, true);
+ ls_intc_set_bit(gc, LS3_REG_INTC_POL, mask, false);
+ break;
+ default:
+ return -EINVAL;
+ }
+ irq_gc_unlock_irqrestore(gc, flags);
+
+ irqd_set_trigger_type(data, type);
+ return 0;
+}
+
+static int ls_intc_set_affinity(struct irq_data *idata,
+ const cpumask_t *cpu_mask, bool force)
+{
+ return -ENAVAIL;
+}
+
+static int ls3_iointc_irq_domain_xlate(struct irq_domain *d,
+ struct device_node *ctrlr,
+ const u32 *intspec, unsigned int intsize,
+ unsigned long *out_hwirq,
+ unsigned int *out_type)
+{
+ struct ls3_iointc_priv *priv = d->host_data;
+ struct irq_chip_generic *gc;
+ int err;
+ unsigned long flags;
+
+ /* Call the generic xlate to process first two cells */
+ err = irq_domain_xlate_onetwocell(d, ctrlr, intspec,
+ intsize, out_hwirq, out_type);
+ if (err)
+ return err;
+ /* If we only have two cells, don't process map information */
+ if (intsize <= 2)
+ return 0;
+ else if (intsize != 4)
+ return -EINVAL; /* Only 4 cells is acceptable */
+
+ /* Third cell is the parent interrupt line, fourth is the Core */
+ if (intspec[3] > 5 || intspec[4] > 3)
+ return -EINVAL; /* Check IP & Core */
+
+ gc = irq_get_domain_generic_chip(d, *out_hwirq);
+ priv->map_cache[*out_hwirq] = LS3_MAP_CORE_INT(intspec[4], intspec[3]);
+
+ irq_gc_lock_irqsave(gc, flags);
+ writeb(priv->map_cache[*out_hwirq],
+ gc->reg_base + LS3_REG_INTx_MAP(*out_hwirq));
+ irq_gc_unlock_irqrestore(gc, flags);
+
+ return 0;
+}
+
+static const struct irq_domain_ops ls3_iointc_irq_domain_ops = {
+ .map = irq_map_generic_chip,
+ .unmap = irq_unmap_generic_chip,
+ .xlate = ls3_iointc_irq_domain_xlate,
+};
+
+static void ls3_iointc_resume(struct irq_chip_generic *gc)
+{
+ struct ls3_iointc_priv *priv = gc->private;
+ unsigned long flags;
+ int i;
+
+ irq_gc_lock_irqsave(gc, flags);
+ /* Revert map cache */
+ for (i = 0; i < LS3_CHIP_IRQ; i++)
+ writeb(priv->map_cache[i],
+ gc->reg_base + LS3_REG_INTx_MAP(i));
+
+ /* Revert mask cache */
+ writel(gc->mask_cache, gc->reg_base + LS3_REG_INTC_DISABLE);
+ writel(~gc->mask_cache, gc->reg_base + LS3_REG_INTC_ENABLE);
+ irq_gc_unlock_irqrestore(gc, flags);
+}
+
+int __init ls3_iointc_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 ls3_iointc_priv *priv;
+ void __iomem *intc_base;
+ int parent_irq, err = 0;
+ int core = cpu_logical_map(smp_processor_id());
+ int i;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ intc_base = of_iomap(node, 0);
+ if (!intc_base) {
+ err = -ENODEV;
+ goto out_free_priv;
+ }
+
+ parent_irq = irq_of_parse_and_map(node, 0);
+ if (!parent_irq) {
+ pr_err("ls3-iointc: unable to get parent irq\n");
+ err = -ENODEV;
+ goto out_iounmap;
+ }
+ /* Setup IRQ domain */
+ domain = irq_domain_add_linear(node, 32,
+ &ls3_iointc_irq_domain_ops,
+ priv);
+ if (!domain) {
+ pr_err("ls3-iointc: cannot add IRQ domain\n");
+ err = -ENOMEM;
+ 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("ls3-iointc: unable to register IRQ domain\n");
+ err = -ENOMEM;
+ goto out_free_domain;
+ }
+
+ /*
+ * Initialize the map_cache by routing all the interrupts
+ * to interrupt line 0 of the bootcore
+ */
+ pr_info("ls3-iointc: Mapping All ls3-iointc IRQ to core %d, IP 0\n",
+ core);
+ for (i = 0; i < LS3_CHIP_IRQ; i++) {
+ priv->map_cache[i] = LS3_MAP_CORE_INT(core, 0);
+ writeb(priv->map_cache[i],
+ intc_base + LS3_REG_INTx_MAP(i));
+ }
+
+ /* Disable all IRQs */
+ writel(0xffffffff, intc_base + LS3_REG_INTC_DISABLE);
+ /* Set to level triggered */
+ writel(0x0, intc_base + LS3_REG_INTC_EDGE);
+
+ gc = irq_get_domain_generic_chip(domain, 0);
+ gc->private = priv;
+ gc->reg_base = intc_base;
+ gc->domain = domain;
+ gc->resume = ls3_iointc_resume;
+
+ ct = gc->chip_types;
+ ct->regs.enable = LS3_REG_INTC_ENABLE;
+ ct->regs.disable = LS3_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 = ls_intc_set_type;
+ ct->chip.irq_set_affinity = ls_intc_set_affinity;
+
+ /* Initialize mask_cache by read EN_STATUS register */
+ gc->mask_cache = ~readl(intc_base + LS3_REG_INTC_EN_STATUS);
+
+ irq_set_chained_handler_and_data(parent_irq,
+ ls3_io_chained_handle_irq,
+ gc);
+
+ return 0;
+
+out_free_domain:
+ irq_domain_remove(domain);
+out_iounmap:
+ iounmap(intc_base);
+out_free_priv:
+ kfree(priv);
+
+ return err;
+}
+
+IRQCHIP_DECLARE(ls3_iointc, "loongson,ls3-iointc", ls3_iointc_of_init);
--
2.22.0
