1 files changed, 316 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-imx-irqsteer.c b/drivers/irqchip/irq-imx-irqsteer.c
new file mode 100644
index 000000000..96230a04e
--- /dev/null
+++ b/drivers/irqchip/irq-imx-irqsteer.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2017 NXP
+ * Copyright (C) 2018 Pengutronix, Lucas Stach <kernel@pengutronix.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/spinlock.h>
+
+#define CTRL_STRIDE_OFF(_t, _r)	(_t * 4 * _r)
+#define CHANCTRL		0x0
+#define CHANMASK(n, t)		(CTRL_STRIDE_OFF(t, 0) + 0x4 * (n) + 0x4)
+#define CHANSET(n, t)		(CTRL_STRIDE_OFF(t, 1) + 0x4 * (n) + 0x4)
+#define CHANSTATUS(n, t)	(CTRL_STRIDE_OFF(t, 2) + 0x4 * (n) + 0x4)
+#define CHAN_MINTDIS(t)		(CTRL_STRIDE_OFF(t, 3) + 0x4)
+#define CHAN_MASTRSTAT(t)	(CTRL_STRIDE_OFF(t, 3) + 0x8)
+
+#define CHAN_MAX_OUTPUT_INT	0x8
+
+struct irqsteer_data {
+	void __iomem		*regs;
+	struct clk		*ipg_clk;
+	int			irq[CHAN_MAX_OUTPUT_INT];
+	int			irq_count;
+	raw_spinlock_t		lock;
+	int			reg_num;
+	int			channel;
+	struct irq_domain	*domain;
+	u32			*saved_reg;
+};
+
+static int imx_irqsteer_get_reg_index(struct irqsteer_data *data,
+				      unsigned long irqnum)
+{
+	return (data->reg_num - irqnum / 32 - 1);
+}
+
+static void imx_irqsteer_irq_unmask(struct irq_data *d)
+{
+	struct irqsteer_data *data = d->chip_data;
+	int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
+	unsigned long flags;
+	u32 val;
+
+	raw_spin_lock_irqsave(&data->lock, flags);
+	val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
+	val |= BIT(d->hwirq % 32);
+	writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
+	raw_spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static void imx_irqsteer_irq_mask(struct irq_data *d)
+{
+	struct irqsteer_data *data = d->chip_data;
+	int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
+	unsigned long flags;
+	u32 val;
+
+	raw_spin_lock_irqsave(&data->lock, flags);
+	val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
+	val &= ~BIT(d->hwirq % 32);
+	writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
+	raw_spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static const struct irq_chip imx_irqsteer_irq_chip = {
+	.name		= "irqsteer",
+	.irq_mask	= imx_irqsteer_irq_mask,
+	.irq_unmask	= imx_irqsteer_irq_unmask,
+};
+
+static int imx_irqsteer_irq_map(struct irq_domain *h, unsigned int irq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_status_flags(irq, IRQ_LEVEL);
+	irq_set_chip_data(irq, h->host_data);
+	irq_set_chip_and_handler(irq, &imx_irqsteer_irq_chip, handle_level_irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops imx_irqsteer_domain_ops = {
+	.map		= imx_irqsteer_irq_map,
+	.xlate		= irq_domain_xlate_onecell,
+};
+
+static int imx_irqsteer_get_hwirq_base(struct irqsteer_data *data, u32 irq)
+{
+	int i;
+
+	for (i = 0; i < data->irq_count; i++) {
+		if (data->irq[i] == irq)
+			return i * 64;
+	}
+
+	return -EINVAL;
+}
+
+static void imx_irqsteer_irq_handler(struct irq_desc *desc)
+{
+	struct irqsteer_data *data = irq_desc_get_handler_data(desc);
+	int hwirq;
+	int irq, i;
+
+	chained_irq_enter(irq_desc_get_chip(desc), desc);
+
+	irq = irq_desc_get_irq(desc);
+	hwirq = imx_irqsteer_get_hwirq_base(data, irq);
+	if (hwirq < 0) {
+		pr_warn("%s: unable to get hwirq base for irq %d\n",
+			__func__, irq);
+		return;
+	}
+
+	for (i = 0; i < 2; i++, hwirq += 32) {
+		int idx = imx_irqsteer_get_reg_index(data, hwirq);
+		unsigned long irqmap;
+		int pos;
+
+		if (hwirq >= data->reg_num * 32)
+			break;
+
+		irqmap = readl_relaxed(data->regs +
+				       CHANSTATUS(idx, data->reg_num));
+
+		for_each_set_bit(pos, &irqmap, 32)
+			generic_handle_domain_irq(data->domain, pos + hwirq);
+	}
+
+	chained_irq_exit(irq_desc_get_chip(desc), desc);
+}
+
+static int imx_irqsteer_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct irqsteer_data *data;
+	u32 irqs_num;
+	int i, ret;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->regs)) {
+		dev_err(&pdev->dev, "failed to initialize reg\n");
+		return PTR_ERR(data->regs);
+	}
+
+	data->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
+	if (IS_ERR(data->ipg_clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(data->ipg_clk),
+				     "failed to get ipg clk\n");
+
+	raw_spin_lock_init(&data->lock);
+
+	ret = of_property_read_u32(np, "fsl,num-irqs", &irqs_num);
+	if (ret)
+		return ret;
+	ret = of_property_read_u32(np, "fsl,channel", &data->channel);
+	if (ret)
+		return ret;
+
+	/*
+	 * There is one output irq for each group of 64 inputs.
+	 * One register bit map can represent 32 input interrupts.
+	 */
+	data->irq_count = DIV_ROUND_UP(irqs_num, 64);
+	data->reg_num = irqs_num / 32;
+
+	if (IS_ENABLED(CONFIG_PM)) {
+		data->saved_reg = devm_kzalloc(&pdev->dev,
+					sizeof(u32) * data->reg_num,
+					GFP_KERNEL);
+		if (!data->saved_reg)
+			return -ENOMEM;
+	}
+
+	ret = clk_prepare_enable(data->ipg_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
+		return ret;
+	}
+
+	/* steer all IRQs into configured channel */
+	writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
+
+	data->domain = irq_domain_add_linear(np, data->reg_num * 32,
+					     &imx_irqsteer_domain_ops, data);
+	if (!data->domain) {
+		dev_err(&pdev->dev, "failed to create IRQ domain\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+	irq_domain_set_pm_device(data->domain, &pdev->dev);
+
+	if (!data->irq_count || data->irq_count > CHAN_MAX_OUTPUT_INT) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	for (i = 0; i < data->irq_count; i++) {
+		data->irq[i] = irq_of_parse_and_map(np, i);
+		if (!data->irq[i]) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		irq_set_chained_handler_and_data(data->irq[i],
+						 imx_irqsteer_irq_handler,
+						 data);
+	}
+
+	platform_set_drvdata(pdev, data);
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+out:
+	clk_disable_unprepare(data->ipg_clk);
+	return ret;
+}
+
+static int imx_irqsteer_remove(struct platform_device *pdev)
+{
+	struct irqsteer_data *irqsteer_data = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < irqsteer_data->irq_count; i++)
+		irq_set_chained_handler_and_data(irqsteer_data->irq[i],
+						 NULL, NULL);
+
+	irq_domain_remove(irqsteer_data->domain);
+
+	clk_disable_unprepare(irqsteer_data->ipg_clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static void imx_irqsteer_save_regs(struct irqsteer_data *data)
+{
+	int i;
+
+	for (i = 0; i < data->reg_num; i++)
+		data->saved_reg[i] = readl_relaxed(data->regs +
+						CHANMASK(i, data->reg_num));
+}
+
+static void imx_irqsteer_restore_regs(struct irqsteer_data *data)
+{
+	int i;
+
+	writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
+	for (i = 0; i < data->reg_num; i++)
+		writel_relaxed(data->saved_reg[i],
+			       data->regs + CHANMASK(i, data->reg_num));
+}
+
+static int imx_irqsteer_suspend(struct device *dev)
+{
+	struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
+
+	imx_irqsteer_save_regs(irqsteer_data);
+	clk_disable_unprepare(irqsteer_data->ipg_clk);
+
+	return 0;
+}
+
+static int imx_irqsteer_resume(struct device *dev)
+{
+	struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(irqsteer_data->ipg_clk);
+	if (ret) {
+		dev_err(dev, "failed to enable ipg clk: %d\n", ret);
+		return ret;
+	}
+	imx_irqsteer_restore_regs(irqsteer_data);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops imx_irqsteer_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				      pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(imx_irqsteer_suspend,
+			   imx_irqsteer_resume, NULL)
+};
+
+static const struct of_device_id imx_irqsteer_dt_ids[] = {
+	{ .compatible = "fsl,imx-irqsteer", },
+	{},
+};
+
+static struct platform_driver imx_irqsteer_driver = {
+	.driver = {
+		.name = "imx-irqsteer",
+		.of_match_table = imx_irqsteer_dt_ids,
+		.pm = &imx_irqsteer_pm_ops,
+	},
+	.probe = imx_irqsteer_probe,
+	.remove = imx_irqsteer_remove,
+};
+builtin_platform_driver(imx_irqsteer_driver);