2019-09-05 16:26:59

by Jiaxun Yang

[permalink] [raw]
Subject: [PATCH v2 07/19] irqchip: Add driver for Loongson-3 HyperTransport interrupt controller

This controller appeared on Loongson-3 family of chips to receive interrupts
from PCH chip.

Signed-off-by: Jiaxun Yang <[email protected]>
---
drivers/irqchip/Kconfig | 8 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-ls3-htintc.c | 147 +++++++++++++++++++++++++++++++
3 files changed, 156 insertions(+)
create mode 100644 drivers/irqchip/irq-ls3-htintc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 4acf38a20a2c..d415fb13f3d5 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -492,6 +492,14 @@ config LS3_IOINTC
help
Support for the Loongson-3 I/O Interrupt Controller.

+config LS3_HTINTC
+ bool "Loongson3 HyperTransport Interrupt Controller"
+ depends on MACH_LOONGSON64
+ default y
+ select IRQ_DOMAIN
+ select GENERIC_IRQ_CHIP
+ help
+ Support for the Loongson-3 HyperTransport Interrupt Controller.
endmenu

config SIFIVE_PLIC
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 18ba8f203afd..ab03ad7d421c 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -104,3 +104,4 @@ 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
+obj-$(CONFIG_LS3_HTINTC) += irq-ls3-htintc.o
diff --git a/drivers/irqchip/irq-ls3-htintc.c b/drivers/irqchip/irq-ls3-htintc.c
new file mode 100644
index 000000000000..d5013606faa8
--- /dev/null
+++ b/drivers/irqchip/irq-ls3-htintc.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019, Jiaxun Yang <[email protected]>
+ * Loongson-3 HyperTransport 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/irqchip/chained_irq.h>
+
+#define HTINTC_NUM_GC 4
+#define HTINTC_GC_SIZE 0x4
+#define HTINTC_NUM_HANDLER 4
+#define HTINTC_HANDLER_SIZE 0x8
+#define HTINTC_HANDLER_IRQ 64
+
+#define HTINTC_VECTOR_OFFSET 0x0
+#define HTINTC_EN_OFFSET 0x20
+
+struct htintc_handler_priv {
+ struct irq_domain *domain;
+ void __iomem *handler_base;
+};
+
+static void htintc_chained_handle_irq(struct irq_desc *desc)
+{
+ struct htintc_handler_priv *priv = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ int i;
+ bool handled = false;
+
+ chained_irq_enter(chip, desc);
+
+ for (i = 0; i < HTINTC_NUM_GC; i++) {
+ uint32_t irqs = readl(priv->handler_base + HTINTC_GC_SIZE * i);
+
+ while (irqs) {
+ int bit = __ffs(irqs);
+
+ generic_handle_irq(irq_find_mapping(priv->domain, bit + 32 * i));
+ irqs &= ~BIT(bit);
+ handled = true;
+ }
+ }
+
+ if (!handled)
+ spurious_interrupt();
+
+ chained_irq_exit(chip, desc);
+}
+
+int __init ls3_htintc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ struct htintc_handler_priv *priv;
+ struct irq_domain *domain;
+ void __iomem *base;
+ int parent_irq[HTINTC_NUM_HANDLER], err = 0;
+ int i;
+
+ 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 < HTINTC_NUM_HANDLER; i++) {
+ parent_irq[i] = irq_of_parse_and_map(node, i);
+ if (!parent_irq[i]) {
+ pr_err("ls3-htintc: unable to get parent irq %d\n", i);
+ err = -ENODEV;
+ goto out_iounmap;
+ }
+ }
+ /* Set up an IRQ domain */
+ domain = irq_domain_add_linear(node, 32 * HTINTC_NUM_GC,
+ &irq_generic_chip_ops, NULL);
+ if (!domain) {
+ pr_err("ls3-htintc: cannot add IRQ domain\n");
+ err = -ENOMEM;
+ goto out_iounmap;
+ }
+
+ for (i = 0; i < HTINTC_NUM_HANDLER; i++) {
+ /* Mask all interrupts */
+ writeq(0x0, base + HTINTC_EN_OFFSET + HTINTC_HANDLER_SIZE * i);
+ }
+
+ err = irq_alloc_domain_generic_chips(domain, 32, 1,
+ node->full_name,
+ handle_edge_irq,
+ IRQ_NOPROBE, 0,
+ IRQ_GC_INIT_MASK_CACHE);
+ if (err) {
+ pr_err("ls3-htintc: unable to register IRQ domain\n");
+ err = -ENOMEM;
+ goto out_free_domain;
+ }
+
+ for (i = 0; i < HTINTC_NUM_GC; i++) {
+ gc = irq_get_domain_generic_chip(domain, i * 32);
+ gc->reg_base = base + HTINTC_GC_SIZE * i;
+ gc->domain = domain;
+
+ ct = gc->chip_types;
+ ct->regs.mask = HTINTC_EN_OFFSET;
+ ct->regs.ack = HTINTC_VECTOR_OFFSET;
+ ct->chip.irq_unmask = irq_gc_mask_set_bit;
+ ct->chip.irq_mask = irq_gc_mask_clr_bit;
+ ct->chip.irq_ack = irq_gc_ack_set_bit;
+ }
+
+ priv->domain = domain;
+ priv->handler_base = base + HTINTC_VECTOR_OFFSET;
+
+ for (i = 0; i < HTINTC_NUM_HANDLER; i++) {
+ irq_set_chained_handler_and_data(parent_irq[i],
+ htintc_chained_handle_irq,
+ priv);
+ }
+
+ return 0;
+
+out_free_domain:
+ irq_domain_remove(domain);
+out_iounmap:
+ iounmap(base);
+out_free_priv:
+ kfree(priv);
+
+ return err;
+}
+
+IRQCHIP_DECLARE(ls3_htintc, "loongson,ls3-htintc", ls3_htintc_of_init);
--
2.22.0