[PATCH v2 08/16] drm/imx: Add i.MX8qxp Display Controller interrupt controller

[Liu Ying]

i.MX8qxp Display Controller has a built-in interrupt controller to support
Enable/Status/Preset/Clear interrupt bit.  Add driver for it.

Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
---
v2:
* No change.

 drivers/gpu/drm/imx/dc/Kconfig  |   1 +
 drivers/gpu/drm/imx/dc/Makefile |   2 +-
 drivers/gpu/drm/imx/dc/dc-drv.c |   1 +
 drivers/gpu/drm/imx/dc/dc-drv.h |   1 +
 drivers/gpu/drm/imx/dc/dc-ic.c  | 249 ++++++++++++++++++++++++++++++++
 5 files changed, 253 insertions(+), 1 deletion(-)
 create mode 100644 drivers/gpu/drm/imx/dc/dc-ic.c

diff --git a/drivers/gpu/drm/imx/dc/Kconfig b/drivers/gpu/drm/imx/dc/Kconfig
index 32d7471c49d0..b66b815fbdf1 100644
--- a/drivers/gpu/drm/imx/dc/Kconfig
+++ b/drivers/gpu/drm/imx/dc/Kconfig
@@ -1,5 +1,6 @@
 config DRM_IMX8_DC
 	tristate "Freescale i.MX8 Display Controller Graphics"
 	depends on DRM && COMMON_CLK && OF && (ARCH_MXC || COMPILE_TEST)
+	select GENERIC_IRQ_CHIP
 	help
 	  enable Freescale i.MX8 Display Controller(DC) graphics support
diff --git a/drivers/gpu/drm/imx/dc/Makefile b/drivers/gpu/drm/imx/dc/Makefile
index 2942ae6fd5bd..1ce3e8a8db22 100644
--- a/drivers/gpu/drm/imx/dc/Makefile
+++ b/drivers/gpu/drm/imx/dc/Makefile
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
 imx8-dc-drm-objs := dc-cf.o dc-de.o dc-drv.o dc-ed.o dc-fg.o dc-fl.o dc-fu.o \
-		    dc-fw.o dc-lb.o dc-pe.o dc-tc.o
+		    dc-fw.o dc-ic.o dc-lb.o dc-pe.o dc-tc.o
 
 obj-$(CONFIG_DRM_IMX8_DC) += imx8-dc-drm.o
diff --git a/drivers/gpu/drm/imx/dc/dc-drv.c b/drivers/gpu/drm/imx/dc/dc-drv.c
index 7c64acc863ad..fd68861f770a 100644
--- a/drivers/gpu/drm/imx/dc/dc-drv.c
+++ b/drivers/gpu/drm/imx/dc/dc-drv.c
@@ -15,6 +15,7 @@ static struct platform_driver * const dc_drivers[] = {
 	&dc_fg_driver,
 	&dc_fl_driver,
 	&dc_fw_driver,
+	&dc_ic_driver,
 	&dc_lb_driver,
 	&dc_pe_driver,
 	&dc_tc_driver,
diff --git a/drivers/gpu/drm/imx/dc/dc-drv.h b/drivers/gpu/drm/imx/dc/dc-drv.h
index c687a36b8153..3b11f4862c6c 100644
--- a/drivers/gpu/drm/imx/dc/dc-drv.h
+++ b/drivers/gpu/drm/imx/dc/dc-drv.h
@@ -25,6 +25,7 @@ extern struct platform_driver dc_de_driver;
 extern struct platform_driver dc_fg_driver;
 extern struct platform_driver dc_fl_driver;
 extern struct platform_driver dc_fw_driver;
+extern struct platform_driver dc_ic_driver;
 extern struct platform_driver dc_lb_driver;
 extern struct platform_driver dc_pe_driver;
 extern struct platform_driver dc_tc_driver;
diff --git a/drivers/gpu/drm/imx/dc/dc-ic.c b/drivers/gpu/drm/imx/dc/dc-ic.c
new file mode 100644
index 000000000000..8540a0414b39
--- /dev/null
+++ b/drivers/gpu/drm/imx/dc/dc-ic.c
@@ -0,0 +1,249 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2024 NXP
+ */
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/drm_managed.h>
+
+#include "dc-drv.h"
+
+#define USERINTERRUPTMASK(n)	(0x8 + 4 * (n))
+#define INTERRUPTENABLE(n)	(0x10 + 4 * (n))
+#define INTERRUPTCLEAR(n)	(0x20 + 4 * (n))
+#define INTERRUPTSTATUS(n)	(0x28 + 4 * (n))
+#define USERINTERRUPTENABLE(n)	(0x40 + 4 * (n))
+#define USERINTERRUPTCLEAR(n)	(0x50 + 4 * (n))
+#define USERINTERRUPTSTATUS(n)	(0x58 + 4 * (n))
+
+#define IRQ_COUNT	49
+#define IRQ_RESERVED	35
+#define REG_NUM		2
+
+struct dc_ic_data {
+	void __iomem		*regs;
+	struct clk		*clk_axi;
+	int			irq[IRQ_COUNT];
+	struct irq_domain	*domain;
+};
+
+struct dc_ic_entry {
+	struct dc_ic_data *data;
+	int irq;
+};
+
+static void dc_ic_irq_handler(struct irq_desc *desc)
+{
+	struct dc_ic_entry *entry = irq_desc_get_handler_data(desc);
+	struct dc_ic_data *data = entry->data;
+	unsigned int virq;
+	u32 status;
+
+	chained_irq_enter(irq_desc_get_chip(desc), desc);
+
+	status = readl(data->regs + USERINTERRUPTSTATUS(entry->irq / 32));
+	status &= readl(data->regs + USERINTERRUPTENABLE(entry->irq / 32));
+
+	if (status & BIT(entry->irq % 32)) {
+		virq = irq_linear_revmap(data->domain, entry->irq);
+		if (virq)
+			generic_handle_irq(virq);
+	}
+
+	chained_irq_exit(irq_desc_get_chip(desc), desc);
+}
+
+static const unsigned long unused_irq[REG_NUM] = {0x00000000, 0xfffe0008};
+
+static int
+dc_ic_bind(struct device *dev, struct device *master, void *master_data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct dc_drm_device *dc_drm = master_data;
+	struct dc_ic_entry *entry;
+	struct irq_chip_generic *gc;
+	struct dc_ic_data *data;
+	struct irq_chip_type *ct;
+	int i, ret;
+
+	data = drmm_kzalloc(&dc_drm->base, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	entry = drmm_kcalloc(&dc_drm->base, IRQ_COUNT, sizeof(*entry),
+			     GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	data->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->regs)) {
+		dev_err(dev, "failed to initialize reg\n");
+		return PTR_ERR(data->regs);
+	}
+
+	data->clk_axi = devm_clk_get(dev, NULL);
+	if (IS_ERR(data->clk_axi))
+		return dev_err_probe(dev, PTR_ERR(data->clk_axi),
+				     "failed to get AXI clock\n");
+
+	dev_set_drvdata(dev, data);
+
+	ret = devm_pm_runtime_enable(dev);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0) {
+		dev_err(dev, "failed to get runtime PM sync: %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < REG_NUM; i++) {
+		/* mask and clear all interrupts */
+		writel(0x0, data->regs + USERINTERRUPTENABLE(i));
+		writel(0x0, data->regs + INTERRUPTENABLE(i));
+		writel(0xffffffff, data->regs + USERINTERRUPTCLEAR(i));
+		writel(0xffffffff, data->regs + INTERRUPTCLEAR(i));
+
+		/* set all interrupts to user mode */
+		writel(0xffffffff, data->regs + USERINTERRUPTMASK(i));
+	}
+
+	data->domain = irq_domain_add_linear(dev->of_node, IRQ_COUNT,
+					     &irq_generic_chip_ops, data);
+	if (!data->domain) {
+		dev_err(dev, "failed to create IRQ domain\n");
+		pm_runtime_put(dev);
+		return -ENOMEM;
+	}
+	irq_domain_set_pm_device(data->domain, &pdev->dev);
+
+	ret = irq_alloc_domain_generic_chips(data->domain, 32, 1, "DC",
+					     handle_level_irq, 0, 0, 0);
+	if (ret) {
+		dev_err(dev, "failed to alloc generic IRQ chips: %d\n", ret);
+		irq_domain_remove(data->domain);
+		pm_runtime_put(dev);
+		return ret;
+	}
+
+	for (i = 0; i < IRQ_COUNT; i += 32) {
+		gc = irq_get_domain_generic_chip(data->domain, i);
+		gc->reg_base = data->regs;
+		gc->unused = unused_irq[i / 32];
+		ct = gc->chip_types;
+		ct->chip.irq_ack = irq_gc_ack_set_bit;
+		ct->chip.irq_mask = irq_gc_mask_clr_bit;
+		ct->chip.irq_unmask = irq_gc_mask_set_bit;
+		ct->regs.ack = USERINTERRUPTCLEAR(i / 32);
+		ct->regs.mask = USERINTERRUPTENABLE(i / 32);
+	}
+
+	for (i = 0; i < IRQ_COUNT; i++) {
+		/* skip the reserved IRQ */
+		if (i == IRQ_RESERVED)
+			continue;
+
+		data->irq[i] = irq_of_parse_and_map(dev->of_node, i);
+
+		entry[i].data = data;
+		entry[i].irq = i;
+
+		irq_set_chained_handler_and_data(data->irq[i],
+						 dc_ic_irq_handler, &entry[i]);
+	}
+
+	return 0;
+}
+
+static void
+dc_ic_unbind(struct device *dev, struct device *master, void *master_data)
+{
+	struct dc_ic_data *data = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < IRQ_COUNT; i++) {
+		if (i == IRQ_RESERVED)
+			continue;
+
+		irq_set_chained_handler_and_data(data->irq[i], NULL, NULL);
+	}
+
+	irq_domain_remove(data->domain);
+
+	pm_runtime_put_sync(dev);
+}
+
+static const struct component_ops dc_ic_ops = {
+	.bind = dc_ic_bind,
+	.unbind = dc_ic_unbind,
+};
+
+static int dc_ic_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	ret = component_add(&pdev->dev, &dc_ic_ops);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "failed to add component\n");
+
+	return 0;
+}
+
+static void dc_ic_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &dc_ic_ops);
+}
+
+static int dc_ic_runtime_suspend(struct device *dev)
+{
+	struct dc_ic_data *data = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(data->clk_axi);
+
+	return 0;
+}
+
+static int dc_ic_runtime_resume(struct device *dev)
+{
+	struct dc_ic_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(data->clk_axi);
+	if (ret)
+		dev_err(dev, "failed to enable AXI clock: %d\n", ret);
+
+	return ret;
+}
+
+static const struct dev_pm_ops dc_ic_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				      pm_runtime_force_resume)
+	RUNTIME_PM_OPS(dc_ic_runtime_suspend, dc_ic_runtime_resume, NULL)
+};
+
+static const struct of_device_id dc_ic_dt_ids[] = {
+	{ .compatible = "fsl,imx8qxp-dc-intc", },
+	{ /* sentinel */ }
+};
+
+struct platform_driver dc_ic_driver = {
+	.probe = dc_ic_probe,
+	.remove_new = dc_ic_remove,
+	.driver = {
+		.name = "imx8-dc-intc",
+		.of_match_table	= dc_ic_dt_ids,
+		.pm = pm_sleep_ptr(&dc_ic_pm_ops),
+	},
+};
-- 
2.34.1