1 files changed, 297 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
new file mode 100644
index 0000000..4dd3eb8
--- /dev/null
+++ b/drivers/irqchip/irq-mbigen.c
@@ -0,0 +1,297 @@
+/*
+ * Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
+ * Author: Jun Ma <majun258@huawei.com>
+ * Author: Yun Wu <wuyun.wu@huawei.com>
+ *
+ * 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/interrupt.h>
+#include <linux/irqchip.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* Interrupt numbers per mbigen node supported */
+#define IRQS_PER_MBIGEN_NODE		128
+
+/* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
+#define RESERVED_IRQ_PER_MBIGEN_CHIP	64
+
+/* The maximum IRQ pin number of mbigen chip(start from 0) */
+#define MAXIMUM_IRQ_PIN_NUM		1407
+
+/**
+ * In mbigen vector register
+ * bit[21:12]:	event id value
+ * bit[11:0]:	device id
+ */
+#define IRQ_EVENT_ID_SHIFT		12
+#define IRQ_EVENT_ID_MASK		0x3ff
+
+/* register range of each mbigen node */
+#define MBIGEN_NODE_OFFSET		0x1000
+
+/* offset of vector register in mbigen node */
+#define REG_MBIGEN_VEC_OFFSET		0x200
+
+/**
+ * offset of clear register in mbigen node
+ * This register is used to clear the status
+ * of interrupt
+ */
+#define REG_MBIGEN_CLEAR_OFFSET		0xa000
+
+/**
+ * offset of interrupt type register
+ * This register is used to configure interrupt
+ * trigger type
+ */
+#define REG_MBIGEN_TYPE_OFFSET		0x0
+
+/**
+ * struct mbigen_device - holds the information of mbigen device.
+ *
+ * @pdev:		pointer to the platform device structure of mbigen chip.
+ * @base:		mapped address of this mbigen chip.
+ */
+struct mbigen_device {
+	struct platform_device	*pdev;
+	void __iomem		*base;
+};
+
+static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
+{
+	unsigned int nid, pin;
+
+	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
+	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
+	pin = hwirq % IRQS_PER_MBIGEN_NODE;
+
+	return pin * 4 + nid * MBIGEN_NODE_OFFSET
+			+ REG_MBIGEN_VEC_OFFSET;
+}
+
+static inline void get_mbigen_type_reg(irq_hw_number_t hwirq,
+					u32 *mask, u32 *addr)
+{
+	unsigned int nid, irq_ofst, ofst;
+
+	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
+	nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
+	irq_ofst = hwirq % IRQS_PER_MBIGEN_NODE;
+
+	*mask = 1 << (irq_ofst % 32);
+	ofst = irq_ofst / 32 * 4;
+
+	*addr = ofst + nid * MBIGEN_NODE_OFFSET
+		+ REG_MBIGEN_TYPE_OFFSET;
+}
+
+static inline void get_mbigen_clear_reg(irq_hw_number_t hwirq,
+					u32 *mask, u32 *addr)
+{
+	unsigned int ofst;
+
+	hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
+	ofst = hwirq / 32 * 4;
+
+	*mask = 1 << (hwirq % 32);
+	*addr = ofst + REG_MBIGEN_CLEAR_OFFSET;
+}
+
+static void mbigen_eoi_irq(struct irq_data *data)
+{
+	void __iomem *base = data->chip_data;
+	u32 mask, addr;
+
+	get_mbigen_clear_reg(data->hwirq, &mask, &addr);
+
+	writel_relaxed(mask, base + addr);
+
+	irq_chip_eoi_parent(data);
+}
+
+static int mbigen_set_type(struct irq_data *data, unsigned int type)
+{
+	void __iomem *base = data->chip_data;
+	u32 mask, addr, val;
+
+	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
+		return -EINVAL;
+
+	get_mbigen_type_reg(data->hwirq, &mask, &addr);
+
+	val = readl_relaxed(base + addr);
+
+	if (type == IRQ_TYPE_LEVEL_HIGH)
+		val |= mask;
+	else
+		val &= ~mask;
+
+	writel_relaxed(val, base + addr);
+
+	return 0;
+}
+
+static struct irq_chip mbigen_irq_chip = {
+	.name =			"mbigen-v2",
+	.irq_mask =		irq_chip_mask_parent,
+	.irq_unmask =		irq_chip_unmask_parent,
+	.irq_eoi =		mbigen_eoi_irq,
+	.irq_set_type =		mbigen_set_type,
+	.irq_set_affinity =	irq_chip_set_affinity_parent,
+};
+
+static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+	struct irq_data *d = irq_get_irq_data(desc->irq);
+	void __iomem *base = d->chip_data;
+	u32 val;
+
+	base += get_mbigen_vec_reg(d->hwirq);
+	val = readl_relaxed(base);
+
+	val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
+	val |= (msg->data << IRQ_EVENT_ID_SHIFT);
+
+	/* The address of doorbell is encoded in mbigen register by default
+	 * So,we don't need to program the doorbell address at here
+	 */
+	writel_relaxed(val, base);
+}
+
+static int mbigen_domain_translate(struct irq_domain *d,
+				    struct irq_fwspec *fwspec,
+				    unsigned long *hwirq,
+				    unsigned int *type)
+{
+	if (is_of_node(fwspec->fwnode)) {
+		if (fwspec->param_count != 2)
+			return -EINVAL;
+
+		if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
+			(fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
+			return -EINVAL;
+		else
+			*hwirq = fwspec->param[0];
+
+		/* If there is no valid irq type, just use the default type */
+		if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
+			(fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
+			*type = fwspec->param[1];
+		else
+			return -EINVAL;
+
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static int mbigen_irq_domain_alloc(struct irq_domain *domain,
+					unsigned int virq,
+					unsigned int nr_irqs,
+					void *args)
+{
+	struct irq_fwspec *fwspec = args;
+	irq_hw_number_t hwirq;
+	unsigned int type;
+	struct mbigen_device *mgn_chip;
+	int i, err;
+
+	err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
+	if (err)
+		return err;
+
+	err = platform_msi_domain_alloc(domain, virq, nr_irqs);
+	if (err)
+		return err;
+
+	mgn_chip = platform_msi_get_host_data(domain);
+
+	for (i = 0; i < nr_irqs; i++)
+		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+				      &mbigen_irq_chip, mgn_chip->base);
+
+	return 0;
+}
+
+static struct irq_domain_ops mbigen_domain_ops = {
+	.translate	= mbigen_domain_translate,
+	.alloc		= mbigen_irq_domain_alloc,
+	.free		= irq_domain_free_irqs_common,
+};
+
+static int mbigen_device_probe(struct platform_device *pdev)
+{
+	struct mbigen_device *mgn_chip;
+	struct resource *res;
+	struct irq_domain *domain;
+	u32 num_pins;
+
+	mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
+	if (!mgn_chip)
+		return -ENOMEM;
+
+	mgn_chip->pdev = pdev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mgn_chip->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mgn_chip->base))
+		return PTR_ERR(mgn_chip->base);
+
+	if (of_property_read_u32(pdev->dev.of_node, "num-pins", &num_pins) < 0) {
+		dev_err(&pdev->dev, "No num-pins property\n");
+		return -EINVAL;
+	}
+
+	domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
+							mbigen_write_msg,
+							&mbigen_domain_ops,
+							mgn_chip);
+
+	if (!domain)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, mgn_chip);
+
+	dev_info(&pdev->dev, "Allocated %d MSIs\n", num_pins);
+
+	return 0;
+}
+
+static const struct of_device_id mbigen_of_match[] = {
+	{ .compatible = "hisilicon,mbigen-v2" },
+	{ /* END */ }
+};
+MODULE_DEVICE_TABLE(of, mbigen_of_match);
+
+static struct platform_driver mbigen_platform_driver = {
+	.driver = {
+		.name		= "Hisilicon MBIGEN-V2",
+		.owner		= THIS_MODULE,
+		.of_match_table	= mbigen_of_match,
+	},
+	.probe			= mbigen_device_probe,
+};
+
+module_platform_driver(mbigen_platform_driver);
+
+MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
+MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Hisilicon MBI Generator driver");