[PATCH v2 04/10] MIPS: ranchu: Add Goldfish PIC driver
From: Aleksandar Markovic
Date: Wed Jun 28 2017 - 12:02:15 EST
From: Aleksandar Markovic <aleksandar.markovic@xxxxxxxxxx>
Add device driver for a virtual programmable interrupt controller
The virtual PIC is designed as a device tree-based interrupt controller.
The compatible string used by OS for binding the driver is
"google,goldfish-pic".
Signed-off-by: Miodrag Dinic <miodrag.dinic@xxxxxxxxxx>
Signed-off-by: Goran Ferenc <goran.ferenc@xxxxxxxxxx>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@xxxxxxxxxx>
---
MAINTAINERS | 1 +
drivers/irqchip/Kconfig | 9 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-goldfish-pic.c | 169 +++++++++++++++++++++++++++++++++++++
4 files changed, 180 insertions(+)
create mode 100644 drivers/irqchip/irq-goldfish-pic.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 85da9f0..fb4c6ea 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -845,6 +845,7 @@ ANDROID GOLDFISH PIC DRIVER
M: Miodrag Dinic <miodrag.dinic@xxxxxxxxxx>
S: Supported
F: Documentation/devicetree/bindings/interrupt-controller/google,goldfish-pic.txt
+F: drivers/irqchip/irq-goldfish-pic.c
ANDROID GOLDFISH RTC DRIVER
M: Miodrag Dinic <miodrag.dinic@xxxxxxxxxx>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 478f8ac..6c2f924 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -301,3 +301,12 @@ config QCOM_IRQ_COMBINER
help
Say yes here to add support for the IRQ combiner devices embedded
in Qualcomm Technologies chips.
+
+config GOLDFISH_PIC
+ bool "Goldfish programmable interrupt controller"
+ depends on MIPS
+ depends on GOLDFISH
+ select IRQ_DOMAIN
+ help
+ Say yes here to enable Goldfish interrupt controller driver used
+ for Goldfish based virtual platforms.
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index b64c59b..5e73932 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -76,3 +76,4 @@ obj-$(CONFIG_EZNPS_GIC) += irq-eznps.o
obj-$(CONFIG_ARCH_ASPEED) += irq-aspeed-vic.o
obj-$(CONFIG_STM32_EXTI) += irq-stm32-exti.o
obj-$(CONFIG_QCOM_IRQ_COMBINER) += qcom-irq-combiner.o
+obj-$(CONFIG_GOLDFISH_PIC) += irq-goldfish-pic.o
diff --git a/drivers/irqchip/irq-goldfish-pic.c b/drivers/irqchip/irq-goldfish-pic.c
new file mode 100644
index 0000000..d0e4c2d
--- /dev/null
+++ b/drivers/irqchip/irq-goldfish-pic.c
@@ -0,0 +1,169 @@
+/* drivers/irqchip/irq-goldfish-pic.c
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (C) 2017 Imagination Technologies Ltd.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irqchip.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/setup.h>
+
+/* 0..7 MIPS CPU interrupts */
+#define GOLDFISH_CPU_IRQ_PIC (MIPS_CPU_IRQ_BASE + 2)
+#define GOLDFISH_CPU_IRQ_FIQ (MIPS_CPU_IRQ_BASE + 3) /* Not used? */
+#define GOLDFISH_CPU_IRQ_COMPARE (MIPS_CPU_IRQ_BASE + 7)
+
+#define GOLDFISH_NR_IRQS 40
+/* 8..39 Cascaded Goldfish PIC interrupts */
+#define GOLDFISH_IRQ_OFFSET 8
+
+#define GOLDFISH_PIC_NUMBER 0x04
+#define GOLDFISH_PIC_DISABLE_ALL 0x08
+#define GOLDFISH_PIC_DISABLE 0x0c
+#define GOLDFISH_PIC_ENABLE 0x10
+
+static struct irq_domain *goldfish_pic_domain;
+static void __iomem *goldfish_pic_base;
+
+void goldfish_mask_irq(struct irq_data *d)
+{
+ writel(d->irq - GOLDFISH_IRQ_OFFSET,
+ goldfish_pic_base + GOLDFISH_PIC_DISABLE);
+}
+
+void goldfish_unmask_irq(struct irq_data *d)
+{
+ writel(d->irq - GOLDFISH_IRQ_OFFSET,
+ goldfish_pic_base + GOLDFISH_PIC_ENABLE);
+}
+
+static struct irq_chip goldfish_irq_chip = {
+ .name = "goldfish",
+ .irq_mask = goldfish_mask_irq,
+ .irq_mask_ack = goldfish_mask_irq,
+ .irq_unmask = goldfish_unmask_irq,
+};
+
+void goldfish_irq_dispatch(void)
+{
+ uint32_t irq;
+
+ /*
+ * Disable all interrupt sources
+ */
+ irq = readl(goldfish_pic_base + GOLDFISH_PIC_NUMBER);
+ do_IRQ(GOLDFISH_IRQ_OFFSET + irq);
+}
+
+void goldfish_fiq_dispatch(void)
+{
+ panic("goldfish_fiq_dispatch");
+}
+
+static void goldfish_ip2_irq_dispatch(struct irq_desc *desc)
+{
+ unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+
+ if (pending & CAUSEF_IP2)
+ goldfish_irq_dispatch();
+ else if (pending & CAUSEF_IP3)
+ goldfish_fiq_dispatch();
+ else if (pending & CAUSEF_IP7)
+ do_IRQ(MIPS_CPU_IRQ_BASE + 7);
+ else
+ spurious_interrupt();
+}
+
+static struct irqaction cascade = {
+ .handler = no_action,
+ .flags = IRQF_NO_THREAD,
+ .name = "cascade",
+};
+
+static void mips_timer_dispatch(void)
+{
+ do_IRQ(MIPS_CPU_IRQ_BASE + GOLDFISH_CPU_IRQ_COMPARE);
+}
+
+static int goldfish_pic_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ struct irq_chip *chip = &goldfish_irq_chip;
+
+ if (hw < GOLDFISH_IRQ_OFFSET)
+ return 0;
+
+ irq_set_chip_and_handler(hw, chip, handle_level_irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops irq_domain_ops = {
+ .xlate = irq_domain_xlate_onetwocell,
+ .map = goldfish_pic_map,
+};
+
+int __init goldfish_pic_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct resource res;
+
+ if (of_address_to_resource(node, 0, &res)) {
+ pr_err("%s(): Failed to get icu memory range", __func__);
+ return -ENODEV;
+ }
+
+ if (request_mem_region(res.start, resource_size(&res),
+ res.name) < 0) {
+ pr_err("%s(): Failed to request icu memory", __func__);
+ return -ENOMEM;
+ }
+
+ goldfish_pic_base = ioremap_nocache(res.start, resource_size(&res));
+ if (!goldfish_pic_base) {
+ pr_err("%s(): Failed to remap icu memory", __func__);
+ release_mem_region(res.start, resource_size(&res));
+ return -ENOMEM;
+ }
+
+ /*
+ * Disable all interrupt sources
+ */
+ writel(1, goldfish_pic_base + GOLDFISH_PIC_DISABLE_ALL);
+
+ if (cpu_has_vint) {
+ pr_info("Setting up vectored interrupts\n");
+ set_vi_handler(GOLDFISH_CPU_IRQ_PIC, goldfish_irq_dispatch);
+ set_vi_handler(GOLDFISH_CPU_IRQ_FIQ, goldfish_fiq_dispatch);
+ set_vi_handler(GOLDFISH_CPU_IRQ_COMPARE, mips_timer_dispatch);
+ } else {
+ irq_set_chained_handler(GOLDFISH_CPU_IRQ_PIC,
+ goldfish_ip2_irq_dispatch);
+ }
+
+ setup_irq(MIPS_CPU_IRQ_BASE+GOLDFISH_CPU_IRQ_PIC, &cascade);
+ setup_irq(MIPS_CPU_IRQ_BASE+GOLDFISH_CPU_IRQ_FIQ, &cascade);
+
+ goldfish_pic_domain = irq_domain_add_linear(node, GOLDFISH_NR_IRQS,
+ &irq_domain_ops, 0);
+ if (!goldfish_pic_domain)
+ panic("Failed to add IRQ domain");
+
+ return 0;
+}
+
+IRQCHIP_DECLARE(google_goldfish_pic, "google,goldfish-pic",
+ goldfish_pic_of_init);
--
2.7.4