[PATCH 28/31] irqchip: Andestech Internal Vector Interrupt Controller driver

[Greentime Hu]

From: Greentime Hu <greentime@xxxxxxxxxxxxx>

Signed-off-by: Rick Chen <rick@xxxxxxxxxxxxx>
Signed-off-by: Greentime Hu <greentime@xxxxxxxxxxxxx>
---
 drivers/irqchip/Makefile       |    1 +
 drivers/irqchip/irq-ativic32.c |  149 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 150 insertions(+)
 create mode 100644 drivers/irqchip/irq-ativic32.c

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index b842dfd..201ca9f 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -80,3 +80,4 @@ obj-$(CONFIG_ARCH_ASPEED)		+= irq-aspeed-vic.o irq-aspeed-i2c-ic.o
 obj-$(CONFIG_STM32_EXTI) 		+= irq-stm32-exti.o
 obj-$(CONFIG_QCOM_IRQ_COMBINER)		+= qcom-irq-combiner.o
 obj-$(CONFIG_IRQ_UNIPHIER_AIDET)	+= irq-uniphier-aidet.o
+obj-$(CONFIG_NDS32)			+= irq-ativic32.o
diff --git a/drivers/irqchip/irq-ativic32.c b/drivers/irqchip/irq-ativic32.c
new file mode 100644
index 0000000..d3dae59
--- /dev/null
+++ b/drivers/irqchip/irq-ativic32.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2005-2017 Andes Technology Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include <nds32_intrinsic.h>
+
+static void ativic32_ack_irq(struct irq_data *data)
+{
+	__nds32__mtsr_dsb(1 << data->hwirq, NDS32_SR_INT_PEND2);
+}
+
+static void ativic32_mask_irq(struct irq_data *data)
+{
+	unsigned long int_mask2 = __nds32__mfsr(NDS32_SR_INT_MASK2);
+	__nds32__mtsr_dsb(int_mask2 & (~(1 << data->hwirq)), NDS32_SR_INT_MASK2);
+}
+
+static void ativic32_mask_ack_irq(struct irq_data *data)
+{
+	unsigned long int_mask2 = __nds32__mfsr(NDS32_SR_INT_MASK2);
+	__nds32__mtsr_dsb(int_mask2 & (~(1 << data->hwirq)), NDS32_SR_INT_MASK2);
+	__nds32__mtsr_dsb((1 << data->hwirq), NDS32_SR_INT_PEND2);
+
+}
+
+static void ativic32_unmask_irq(struct irq_data *data)
+{
+	unsigned long int_mask2 = __nds32__mfsr(NDS32_SR_INT_MASK2);
+	__nds32__mtsr_dsb(int_mask2 | (1 << data->hwirq), NDS32_SR_INT_MASK2);
+}
+
+static int ativic32_set_type(struct irq_data *data, unsigned int flow_type)
+{
+	printk(KERN_WARNING "interrupt type is not configurable\n");
+	return 0;
+}
+
+static struct irq_chip ativic32_chip = {
+	.name = "ativic32",
+	.irq_ack = ativic32_ack_irq,
+	.irq_mask = ativic32_mask_irq,
+	.irq_mask_ack = ativic32_mask_ack_irq,
+	.irq_unmask = ativic32_unmask_irq,
+	.irq_set_type = ativic32_set_type,
+};
+
+static unsigned int __initdata nivic_map[6] = { 6, 2, 10, 16, 24, 32 };
+
+struct irq_domain *root_domain;
+static int ativic32_irq_domain_map(struct irq_domain *id, unsigned int virq,
+				  irq_hw_number_t hw)
+{
+
+	unsigned long int_trigger_type;
+	int_trigger_type = __nds32__mfsr(NDS32_SR_INT_TRIGGER);
+	if (int_trigger_type & (1 << hw))
+		irq_set_chip_and_handler(virq, &ativic32_chip, handle_edge_irq);
+	else
+		irq_set_chip_and_handler(virq, &ativic32_chip, handle_level_irq);
+
+	return 0;
+}
+
+static struct irq_domain_ops ativic32_ops = {
+	.map = ativic32_irq_domain_map,
+	.xlate = irq_domain_xlate_onecell
+};
+
+static int get_intr_src(void)
+{
+	return ((__nds32__mfsr(NDS32_SR_ITYPE)&ITYPE_mskVECTOR) >> ITYPE_offVECTOR)
+		- NDS32_VECTOR_offINTERRUPT;
+}
+
+asmlinkage void asm_do_IRQ(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+	int virq;
+	int irq = get_intr_src();
+
+	/*
+	 * Some hardware gives randomly wrong interrupts.  Rather
+	 * than crashing, do something sensible.
+	 */
+	if (unlikely(irq >= NR_IRQS)) {
+		pr_emerg( "IRQ exceeds NR_IRQS\n");
+		BUG();
+	}
+
+	irq_enter();
+	virq = irq_find_mapping(root_domain, irq);
+	generic_handle_irq(virq);
+	irq_exit();
+	set_irq_regs(old_regs);
+
+}
+
+int __init ativic32_init_irq(struct device_node *node, struct device_node *parent)
+{
+	unsigned long int_vec_base, nivic, i;
+
+	if (WARN(parent, "non-root ativic32 are not supported"))
+		return -EINVAL;
+
+	int_vec_base = __nds32__mfsr(NDS32_SR_IVB);
+
+	if (((int_vec_base & IVB_mskIVIC_VER) >> IVB_offIVIC_VER) == 0) {
+		panic("Unable to use NOINTC option to boot on this cpu\n");
+	}
+
+	nivic = (int_vec_base & IVB_mskNIVIC) >> IVB_offNIVIC;
+	if (nivic >= (sizeof nivic_map / sizeof nivic_map[0])) {
+		panic
+		    ("The number of input for IVIC Controller is not supported on this cpu\n");
+	}
+	nivic = nivic_map[nivic];
+
+	root_domain = irq_domain_add_linear(node, nivic,
+			&ativic32_ops, NULL);
+
+	if (!root_domain)
+		panic("%s: unable to create IRQ domain\n", node->full_name);
+
+	for(i = 0; i < nivic; i++)
+		irq_create_mapping(root_domain, i);
+
+	return 0;
+
+}
+IRQCHIP_DECLARE(ativic32, "andestech,ativic32", ativic32_init_irq);
-- 
1.7.9.5