[PATCH v4 5/8] irqchip: Add the ingenic-tcu-intc driver

From: Paul Cercueil
Date: Sat Mar 17 2018 - 19:29:59 EST


This simple driver handles the IRQ chip of the TCU
(Timer Counter Unit) of the JZ47xx Ingenic SoCs.

Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
drivers/irqchip/Kconfig | 6 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-ingenic-tcu.c | 161 ++++++++++++++++++++++++++++++++++++++
3 files changed, 168 insertions(+)
create mode 100644 drivers/irqchip/irq-ingenic-tcu.c

v2: - Use SPDX identifier for the license
- Make KConfig option select CONFIG_IRQ_DOMAIN since we depend on it
v3: - Move documentation to its own patch
- Add comment explaining why we only use IRQCHIP_DECLARE
v4: - Rename variables to avoid splitting long lines
- Add comment about the multiple IRQ parents

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index d913aec85109..2b56587d04ed 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -267,6 +267,12 @@ config INGENIC_IRQ
depends on MACH_INGENIC
default y

+config INGENIC_TCU_IRQ
+ bool
+ depends on MACH_INGENIC || COMPILE_TEST
+ select IRQ_DOMAIN
+ default y
+
config RENESAS_H8300H_INTC
bool
select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index d27e3e3619e0..48b0bdf2b1a2 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -70,6 +70,7 @@ obj-$(CONFIG_RENESAS_H8300H_INTC) += irq-renesas-h8300h.o
obj-$(CONFIG_RENESAS_H8S_INTC) += irq-renesas-h8s.o
obj-$(CONFIG_ARCH_SA1100) += irq-sa11x0.o
obj-$(CONFIG_INGENIC_IRQ) += irq-ingenic.o
+obj-$(CONFIG_INGENIC_TCU_IRQ) += irq-ingenic-tcu.o
obj-$(CONFIG_IMX_GPCV2) += irq-imx-gpcv2.o
obj-$(CONFIG_PIC32_EVIC) += irq-pic32-evic.o
obj-$(CONFIG_MVEBU_GICP) += irq-mvebu-gicp.o
diff --git a/drivers/irqchip/irq-ingenic-tcu.c b/drivers/irqchip/irq-ingenic-tcu.c
new file mode 100644
index 000000000000..add3e9cc6f82
--- /dev/null
+++ b/drivers/irqchip/irq-ingenic-tcu.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * JZ47xx SoCs TCU IRQ driver
+ * Copyright (C) 2018 Paul Cercueil <paul@xxxxxxxxxxxxxxx>
+ */
+
+#include <linux/bitops.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/syscon/ingenic-tcu.h>
+
+static void ingenic_tcu_intc_cascade(struct irq_desc *desc)
+{
+ struct irq_chip *irq_chip = irq_data_get_irq_chip(&desc->irq_data);
+ struct irq_domain *domain = irq_desc_get_handler_data(desc);
+ struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
+ struct regmap *map = gc->private;
+ uint32_t irq_reg, irq_mask;
+ unsigned int i;
+
+ regmap_read(map, TCU_REG_TFR, &irq_reg);
+ regmap_read(map, TCU_REG_TMR, &irq_mask);
+
+ chained_irq_enter(irq_chip, desc);
+
+ irq_reg &= ~irq_mask;
+
+ for (i = 0; i < 32; i++) {
+ if (irq_reg & BIT(i))
+ generic_handle_irq(irq_linear_revmap(domain, i));
+ }
+
+ chained_irq_exit(irq_chip, desc);
+}
+
+static void ingenic_tcu_gc_unmask_enable_reg(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct irq_chip_type *ct = irq_data_get_chip_type(d);
+ struct regmap *map = gc->private;
+ u32 mask = d->mask;
+
+ irq_gc_lock(gc);
+ regmap_write(map, ct->regs.ack, mask);
+ regmap_write(map, ct->regs.enable, mask);
+ *ct->mask_cache |= mask;
+ irq_gc_unlock(gc);
+}
+
+static void ingenic_tcu_gc_mask_disable_reg(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct irq_chip_type *ct = irq_data_get_chip_type(d);
+ struct regmap *map = gc->private;
+ u32 mask = d->mask;
+
+ irq_gc_lock(gc);
+ regmap_write(map, ct->regs.disable, mask);
+ *ct->mask_cache &= ~mask;
+ irq_gc_unlock(gc);
+}
+
+static void ingenic_tcu_gc_mask_disable_reg_and_ack(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct irq_chip_type *ct = irq_data_get_chip_type(d);
+ struct regmap *map = gc->private;
+ u32 mask = d->mask;
+
+ irq_gc_lock(gc);
+ regmap_write(map, ct->regs.ack, mask);
+ regmap_write(map, ct->regs.disable, mask);
+ irq_gc_unlock(gc);
+}
+
+static int __init ingenic_tcu_intc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_domain *domain;
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ int err, i, irqs;
+ u32 parent_irqs[3];
+ struct regmap *map;
+
+ irqs = of_property_count_elems_of_size(node, "interrupts", sizeof(u32));
+ if (irqs < 0 || irqs > ARRAY_SIZE(parent_irqs))
+ return -EINVAL;
+
+ map = syscon_node_to_regmap(node->parent);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops, NULL);
+ if (!domain)
+ return -ENOMEM;
+
+ err = irq_alloc_domain_generic_chips(domain, 32, 1, "TCU",
+ handle_level_irq, 0, IRQ_NOPROBE | IRQ_LEVEL, 0);
+ if (err)
+ goto out_domain_remove;
+
+ gc = irq_get_domain_generic_chip(domain, 0);
+ ct = gc->chip_types;
+
+ gc->wake_enabled = IRQ_MSK(32);
+ gc->private = map;
+
+ ct->regs.disable = TCU_REG_TMSR;
+ ct->regs.enable = TCU_REG_TMCR;
+ ct->regs.ack = TCU_REG_TFCR;
+ ct->chip.irq_unmask = ingenic_tcu_gc_unmask_enable_reg;
+ ct->chip.irq_mask = ingenic_tcu_gc_mask_disable_reg;
+ ct->chip.irq_mask_ack = ingenic_tcu_gc_mask_disable_reg_and_ack;
+ ct->chip.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE;
+
+ /* Mask all IRQs by default */
+ regmap_write(map, TCU_REG_TMSR, IRQ_MSK(32));
+
+ /* On JZ4740, timer 0 and timer 1 have their own interrupt line;
+ * timers 2-7 share one interrupt.
+ * On SoCs >= JZ4770, timer 5 has its own interrupt line;
+ * timers 0-4 and 6-7 share one single interrupt.
+ *
+ * To keep things simple, we just register the same handler to
+ * all parent interrupts. The handler will properly detect which
+ * channel fired the interrupt.
+ */
+ for (i = 0; i < irqs; i++) {
+ parent_irqs[i] = irq_of_parse_and_map(node, i);
+ if (!parent_irqs[i]) {
+ err = -EINVAL;
+ goto out_unmap_irqs;
+ }
+
+ irq_set_chained_handler_and_data(parent_irqs[i],
+ ingenic_tcu_intc_cascade, domain);
+ }
+
+ return 0;
+
+out_unmap_irqs:
+ for (; i > 0; i--)
+ irq_dispose_mapping(parent_irqs[i - 1]);
+out_domain_remove:
+ irq_domain_remove(domain);
+ return err;
+}
+
+/* We only probe via devicetree, no need for a platform driver */
+IRQCHIP_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu-intc",
+ ingenic_tcu_intc_of_init);
+IRQCHIP_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu-intc",
+ ingenic_tcu_intc_of_init);
+IRQCHIP_DECLARE(jz4780_tcu_intc, "ingenic,jz4780-tcu-intc",
+ ingenic_tcu_intc_of_init);
--
2.11.0