[v5,2/5] irqchip: Add RZ/G2L IA55 Interrupt Controller driver

Commit Message

Lad Prabhakar May 23, 2022, 5:42 p.m. UTC

Add a driver for the Renesas RZ/G2L Interrupt Controller.

This supports external pins being used as interrupts. It supports
one line for NMI, 8 external pins and 32 GPIO pins (out of 123)
to be used as IRQ lines.

Signed-off-by: Lad Prabhakar <[e-mail]>
---
 drivers/irqchip/Kconfig             |   8 +
 drivers/irqchip/Makefile            |   1 +
 drivers/irqchip/irq-renesas-rzg2l.c | 425 ++++++++++++++++++++++++++++
 3 files changed, 434 insertions(+)
 create mode 100644 drivers/irqchip/irq-renesas-rzg2l.c

Comments

Marc Zyngier June 25, 2022, 9:30 a.m. UTC | #1

On Mon, 23 May 2022 18:42:35 +0100,
Lad Prabhakar <[e-mail]> wrote:
> 
> Add a driver for the Renesas RZ/G2L Interrupt Controller.
> 
> This supports external pins being used as interrupts. It supports
> one line for NMI, 8 external pins and 32 GPIO pins (out of 123)
> to be used as IRQ lines.
> 
> Signed-off-by: Lad Prabhakar <[e-mail]>
> ---
>  drivers/irqchip/Kconfig             |   8 +
>  drivers/irqchip/Makefile            |   1 +
>  drivers/irqchip/irq-renesas-rzg2l.c | 425 ++++++++++++++++++++++++++++
>  3 files changed, 434 insertions(+)
>  create mode 100644 drivers/irqchip/irq-renesas-rzg2l.c
> 
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index 15edb9a6fcae..f3d071422f3b 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -242,6 +242,14 @@ config RENESAS_RZA1_IRQC
>  	  Enable support for the Renesas RZ/A1 Interrupt Controller, to use up
>  	  to 8 external interrupts with configurable sense select.
>  
> +config RENESAS_RZG2L_IRQC
> +	bool "Renesas RZ/G2L (and alike SoC) IRQC support" if COMPILE_TEST
> +	select GENERIC_IRQ_CHIP
> +	select IRQ_DOMAIN_HIERARCHY
> +	help
> +	  Enable support for the Renesas RZ/G2L (and alike SoC) Interrupt Controller
> +	  for external devices.
> +
>  config SL28CPLD_INTC
>  	bool "Kontron sl28cpld IRQ controller"
>  	depends on MFD_SL28CPLD=y || COMPILE_TEST
> diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
> index 160a1d8ceaa9..eaa56eec2b23 100644
> --- a/drivers/irqchip/Makefile
> +++ b/drivers/irqchip/Makefile
> @@ -51,6 +51,7 @@ obj-$(CONFIG_RDA_INTC)			+= irq-rda-intc.o
>  obj-$(CONFIG_RENESAS_INTC_IRQPIN)	+= irq-renesas-intc-irqpin.o
>  obj-$(CONFIG_RENESAS_IRQC)		+= irq-renesas-irqc.o
>  obj-$(CONFIG_RENESAS_RZA1_IRQC)		+= irq-renesas-rza1.o
> +obj-$(CONFIG_RENESAS_RZG2L_IRQC)	+= irq-renesas-rzg2l.o
>  obj-$(CONFIG_VERSATILE_FPGA_IRQ)	+= irq-versatile-fpga.o
>  obj-$(CONFIG_ARCH_NSPIRE)		+= irq-zevio.o
>  obj-$(CONFIG_ARCH_VT8500)		+= irq-vt8500.o
> diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
> new file mode 100644
> index 000000000000..a846c6ee11d7
> --- /dev/null
> +++ b/drivers/irqchip/irq-renesas-rzg2l.c
> @@ -0,0 +1,425 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Renesas RZ/G2L IRQC Driver
> + *
> + * Copyright (C) 2022 Renesas Electronics Corporation.
> + *
> + * Author: Lad Prabhakar <[e-mail]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/irqchip.h>
> +#include <linux/irqdomain.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> +#include <linux/spinlock.h>
> +
> +#define IRQC_IRQ_START			1
> +#define IRQC_IRQ_COUNT			8
> +#define IRQC_TINT_START			(IRQC_IRQ_START + IRQC_IRQ_COUNT)
> +#define IRQC_TINT_COUNT			32
> +#define IRQC_NUM_IRQ			(IRQC_TINT_START + IRQC_TINT_COUNT)
> +
> +#define ISCR				0x10
> +#define IITSR				0x14
> +#define TSCR				0x20
> +#define TITSR0				0x24
> +#define TITSR1				0x28
> +#define TITSR0_MAX_INT			16
> +#define TITSEL_WIDTH			0x2
> +#define TSSR(n)				(0x30 + ((n) * 4))
> +#define TIEN				BIT(7)
> +#define TSSEL_SHIFT(n)			(8 * (n))
> +#define TSSEL_MASK			GENMASK(7, 0)
> +#define IRQ_MASK			0x3
> +
> +#define TSSR_OFFSET(n)			((n) % 4)
> +#define TSSR_INDEX(n)			((n) / 4)
> +
> +#define TITSR_TITSEL_EDGE_RISING	0
> +#define TITSR_TITSEL_EDGE_FALLING	1
> +#define TITSR_TITSEL_LEVEL_HIGH		2
> +#define TITSR_TITSEL_LEVEL_LOW		3
> +
> +#define IITSR_IITSEL(n, sense)		((sense) << ((n) * 2))
> +#define IITSR_IITSEL_LEVEL_LOW		0
> +#define IITSR_IITSEL_EDGE_FALLING	1
> +#define IITSR_IITSEL_EDGE_RISING	2
> +#define IITSR_IITSEL_EDGE_BOTH		3
> +#define IITSR_IITSEL_MASK(n)		IITSR_IITSEL((n), 3)
> +
> +#define TINT_EXTRACT_HWIRQ(x)           FIELD_GET(GENMASK(15, 0), (x))
> +#define TINT_EXTRACT_GPIOINT(x)         FIELD_GET(GENMASK(31, 16), (x))
> +
> +struct rzg2l_irqc_priv {
> +	void __iomem *base;
> +	struct of_phandle_args map[IRQC_NUM_IRQ];
> +	raw_spinlock_t lock;
> +};
> +
> +struct rzg2l_irqc_chip_data {
> +	int tint;
> +};
> +
> +static struct rzg2l_irqc_priv *irq_data_to_priv(struct irq_data *data)
> +{
> +	return data->domain->host_data;
> +}
> +
> +static void rzg2l_irq_eoi(struct irq_data *d)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
> +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +	u32 bit = BIT(hw_irq);
> +	u32 reg;
> +
> +	reg = readl_relaxed(priv->base + ISCR);
> +	if (reg & bit)
> +		writel_relaxed(reg & ~bit, priv->base + ISCR);
> +}
> +
> +static void rzg2l_tint_eoi(struct irq_data *d)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_TINT_START;
> +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +	u32 bit = BIT(hw_irq);
> +	u32 reg;
> +
> +	reg = readl_relaxed(priv->base + TSCR);
> +	if (reg & bit)
> +		writel_relaxed(reg & ~bit, priv->base + TSCR);
> +}
> +
> +static void rzg2l_irqc_eoi(struct irq_data *d)
> +{
> +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +	unsigned int hw_irq = irqd_to_hwirq(d);
> +
> +	raw_spin_lock(&priv->lock);
> +	if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
> +		rzg2l_irq_eoi(d);
> +	else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
> +		rzg2l_tint_eoi(d);
> +	raw_spin_unlock(&priv->lock);
> +	irq_chip_eoi_parent(d);
> +}
> +
> +static void rzg2l_irqc_irq_disable(struct irq_data *d)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d);
> +
> +	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
> +		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +		u32 offset = hw_irq - IRQC_TINT_START;
> +		u32 tssr_offset = TSSR_OFFSET(offset);
> +		u8 tssr_index = TSSR_INDEX(offset);
> +		u32 reg;
> +
> +		raw_spin_lock(&priv->lock);
> +		reg = readl_relaxed(priv->base + TSSR(tssr_index));
> +		reg &= ~(TSSEL_MASK << tssr_offset);
> +		writel_relaxed(reg, priv->base + TSSR(tssr_index));
> +		raw_spin_unlock(&priv->lock);
> +	}
> +	irq_chip_disable_parent(d);
> +}
> +
> +static void rzg2l_irqc_irq_enable(struct irq_data *d)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d);
> +
> +	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
> +		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +		unsigned long chip_data = *(unsigned long *)d->chip_data;
> +		u32 offset = hw_irq - IRQC_TINT_START;
> +		u32 tssr_offset = TSSR_OFFSET(offset);
> +		u8 tssr_index = TSSR_INDEX(offset);
> +		u32 reg;
> +
> +		raw_spin_lock(&priv->lock);
> +		reg = readl_relaxed(priv->base + TSSR(tssr_index));
> +		reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
> +		writel_relaxed(reg, priv->base + TSSR(tssr_index));
> +		raw_spin_unlock(&priv->lock);
> +	}
> +	irq_chip_enable_parent(d);
> +}
> +
> +static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
> +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +	u16 sense, tmp;
> +
> +	switch (type & IRQ_TYPE_SENSE_MASK) {
> +	case IRQ_TYPE_LEVEL_LOW:
> +		sense = IITSR_IITSEL_LEVEL_LOW;
> +		break;
> +
> +	case IRQ_TYPE_EDGE_FALLING:
> +		sense = IITSR_IITSEL_EDGE_FALLING;
> +		break;
> +
> +	case IRQ_TYPE_EDGE_RISING:
> +		sense = IITSR_IITSEL_EDGE_RISING;
> +		break;
> +
> +	case IRQ_TYPE_EDGE_BOTH:
> +		sense = IITSR_IITSEL_EDGE_BOTH;
> +		break;
> +
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	raw_spin_lock(&priv->lock);
> +	tmp = readl_relaxed(priv->base + IITSR);
> +	tmp &= ~IITSR_IITSEL_MASK(hw_irq);
> +	tmp |= IITSR_IITSEL(hw_irq, sense);
> +	writel_relaxed(tmp, priv->base + IITSR);
> +	raw_spin_unlock(&priv->lock);
> +
> +	return 0;
> +}
> +
> +static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
> +{
> +	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> +	unsigned int hwirq = irqd_to_hwirq(d);
> +	u32 titseln = hwirq - IRQC_TINT_START;
> +	u32 offset;
> +	u8 sense;
> +	u32 reg;
> +
> +	switch (type & IRQ_TYPE_SENSE_MASK) {
> +	case IRQ_TYPE_EDGE_RISING:
> +		sense = TITSR_TITSEL_EDGE_RISING;
> +		break;
> +
> +	case IRQ_TYPE_EDGE_FALLING:
> +		sense = TITSR_TITSEL_EDGE_FALLING;
> +		break;
> +
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	offset = TITSR0;
> +	if (titseln >= TITSR0_MAX_INT) {
> +		titseln -= TITSR0_MAX_INT;
> +		offset = TITSR1;
> +	}
> +
> +	raw_spin_lock(&priv->lock);
> +	reg = readl_relaxed(priv->base + offset);
> +	reg &= ~(IRQ_MASK << (titseln * TITSEL_WIDTH));
> +	reg |= sense << (titseln * TITSEL_WIDTH);
> +	writel_relaxed(reg, priv->base + offset);
> +	raw_spin_unlock(&priv->lock);
> +
> +	return 0;
> +}
> +
> +static int rzg2l_irqc_set_type(struct irq_data *d, unsigned int type)
> +{
> +	unsigned int hw_irq = irqd_to_hwirq(d);
> +	int ret = -EINVAL;
> +
> +	if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
> +		ret = rzg2l_irq_set_type(d, type);
> +	else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
> +		ret = rzg2l_tint_set_edge(d, type);
> +	if (ret)
> +		return ret;
> +
> +	return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
> +}
> +
> +static const struct irq_chip irqc_chip = {
> +	.name			= "rzg2l-irqc",
> +	.irq_eoi		= rzg2l_irqc_eoi,
> +	.irq_mask		= irq_chip_mask_parent,
> +	.irq_unmask		= irq_chip_unmask_parent,
> +	.irq_disable		= rzg2l_irqc_irq_disable,
> +	.irq_enable		= rzg2l_irqc_irq_enable,
> +	.irq_get_irqchip_state	= irq_chip_get_parent_state,
> +	.irq_set_irqchip_state	= irq_chip_set_parent_state,
> +	.irq_retrigger		= irq_chip_retrigger_hierarchy,
> +	.irq_set_type		= rzg2l_irqc_set_type,
> +	.flags			= IRQCHIP_MASK_ON_SUSPEND |
> +				  IRQCHIP_SET_TYPE_MASKED |
> +				  IRQCHIP_SKIP_SET_WAKE,
> +};
> +
> +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> +			    unsigned int nr_irqs, void *arg)
> +{
> +	struct rzg2l_irqc_priv *priv = domain->host_data;
> +	unsigned long *chip_data = NULL;

Why the init to NULL?

> +	struct irq_fwspec spec;
> +	irq_hw_number_t hwirq;
> +	int tint = -EINVAL;
> +	unsigned int type;
> +	unsigned int i;
> +	int ret;
> +
> +	ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * For TINT interrupts ie where pinctrl driver is child of irqc domain
> +	 * the hwirq and TINT are encoded in fwspec->param[0].
> +	 * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> +	 * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> +	 * in IRQC registers to enable a given gpio pin as interrupt.
> +	 */
> +	if (hwirq > IRQC_IRQ_COUNT) {
> +		tint = TINT_EXTRACT_GPIOINT(hwirq);
> +		hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> +
> +		if (hwirq < IRQC_TINT_START)
> +			return -EINVAL;
> +	}
> +
> +	if (hwirq > (IRQC_NUM_IRQ - 1))
> +		return -EINVAL;
> +
> +	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);

Are we really allocating an unsigned long for something that already
fits in something that is pointer-sized?

> +	if (!chip_data)
> +		return -ENOMEM;
> +	*chip_data = tint;

So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
This can't be right.

> +
> +	ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
> +					    chip_data);
> +	if (ret) {
> +		kfree(chip_data);
> +		return ret;
> +	}
> +
> +	spec.fwnode = domain->parent->fwnode;
> +	spec.param_count = priv->map[hwirq].args_count;
> +	for (i = 0; i < spec.param_count; i++)
> +		spec.param[i] = priv->map[hwirq].args[i];

Why isn't that simply:

	spec = priv->map[hwirq];

as this really is the interrupt you want to map to?

> +
> +	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);

or even better:

	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
					   &priv->map[hwirq]);

> +	if (ret)
> +		kfree(chip_data);
> +
> +	return ret;
> +}
> +
> +static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
> +				   unsigned int nr_irqs)
> +{
> +	struct irq_data *d;
> +
> +	d = irq_domain_get_irq_data(domain, virq);
> +	if (d)
> +		kfree(d->chip_data);
> +
> +	irq_domain_free_irqs_common(domain, virq, nr_irqs);
> +}
> +
> +static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
> +	.alloc = rzg2l_irqc_alloc,
> +	.free = rzg2l_irqc_domain_free,
> +	.translate = irq_domain_translate_twocell,
> +};
> +
> +static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
> +				struct device_node *np)
> +{
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < IRQC_NUM_IRQ; i++) {
> +		ret = of_irq_parse_one(np, i, &priv->map[i]);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
> +{
> +	struct irq_domain *irq_domain, *parent_domain;
> +	struct platform_device *pdev;
> +	struct reset_control *resetn;
> +	struct rzg2l_irqc_priv *priv;
> +	int ret;
> +
> +	pdev = of_find_device_by_node(node);
> +	if (!pdev)
> +		return -ENODEV;
> +
> +	parent_domain = irq_find_host(parent);
> +	if (!parent_domain) {
> +		dev_err(&pdev->dev, "cannot find parent domain\n");
> +		return -ENODEV;
> +	}
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	ret = rzg2l_irqc_parse_map(priv, node);
> +	if (ret) {
> +		dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
> +		return ret;
> +	}
> +
> +	resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);
> +	if (IS_ERR(resetn))
> +		return IS_ERR(resetn);
> +
> +	ret = reset_control_deassert(resetn);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
> +		return ret;
> +	}
> +
> +	pm_runtime_enable(&pdev->dev);
> +	ret = pm_runtime_resume_and_get(&pdev->dev);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
> +		goto pm_disable;
> +	}

If using runtime PM, why isn't the core IRQ code made aware of this
dependency by registering the device with irq_domain_set_pm_device()
instead of leaving it enabled forever?

> +
> +	raw_spin_lock_init(&priv->lock);
> +
> +	irq_domain = irq_domain_add_hierarchy(parent_domain, 0, IRQC_NUM_IRQ,
> +					      node, &rzg2l_irqc_domain_ops,
> +					      priv);
> +	if (!irq_domain) {
> +		dev_err(&pdev->dev, "failed to add irq domain\n");
> +		ret = -ENOMEM;
> +		goto pm_put;
> +	}
> +
> +	return 0;
> +
> +pm_put:
> +	pm_runtime_put(&pdev->dev);
> +pm_disable:
> +	pm_runtime_disable(&pdev->dev);
> +	reset_control_assert(resetn);
> +	return ret;
> +}
> +
> +IRQCHIP_PLATFORM_DRIVER_BEGIN(rzg2l_irqc)
> +IRQCHIP_MATCH("renesas,rzg2l-irqc", rzg2l_irqc_init)
> +IRQCHIP_PLATFORM_DRIVER_END(rzg2l_irqc)
> +MODULE_AUTHOR("Lad Prabhakar <[e-mail]>");
> +MODULE_DESCRIPTION("Renesas RZ/G2L IRQC Driver");
> +MODULE_LICENSE("GPL");

	M.

Lad, Prabhakar June 25, 2022, 10:54 a.m. UTC | #2

Hi Marc,

Thank you for the review.

On Sat, Jun 25, 2022 at 10:30 AM Marc Zyngier <[e-mail]> wrote:
>
> On Mon, 23 May 2022 18:42:35 +0100,
> Lad Prabhakar <[e-mail]> wrote:
> >
> > Add a driver for the Renesas RZ/G2L Interrupt Controller.
> >
> > This supports external pins being used as interrupts. It supports
> > one line for NMI, 8 external pins and 32 GPIO pins (out of 123)
> > to be used as IRQ lines.
> >
> > Signed-off-by: Lad Prabhakar <[e-mail]>
> > ---
> >  drivers/irqchip/Kconfig             |   8 +
> >  drivers/irqchip/Makefile            |   1 +
> >  drivers/irqchip/irq-renesas-rzg2l.c | 425 ++++++++++++++++++++++++++++
> >  3 files changed, 434 insertions(+)
> >  create mode 100644 drivers/irqchip/irq-renesas-rzg2l.c
> >
> > diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> > index 15edb9a6fcae..f3d071422f3b 100644
> > --- a/drivers/irqchip/Kconfig
> > +++ b/drivers/irqchip/Kconfig
> > @@ -242,6 +242,14 @@ config RENESAS_RZA1_IRQC
> >         Enable support for the Renesas RZ/A1 Interrupt Controller, to use up
> >         to 8 external interrupts with configurable sense select.
> >
> > +config RENESAS_RZG2L_IRQC
> > +     bool "Renesas RZ/G2L (and alike SoC) IRQC support" if COMPILE_TEST
> > +     select GENERIC_IRQ_CHIP
> > +     select IRQ_DOMAIN_HIERARCHY
> > +     help
> > +       Enable support for the Renesas RZ/G2L (and alike SoC) Interrupt Controller
> > +       for external devices.
> > +
> >  config SL28CPLD_INTC
> >       bool "Kontron sl28cpld IRQ controller"
> >       depends on MFD_SL28CPLD=y || COMPILE_TEST
> > diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
> > index 160a1d8ceaa9..eaa56eec2b23 100644
> > --- a/drivers/irqchip/Makefile
> > +++ b/drivers/irqchip/Makefile
> > @@ -51,6 +51,7 @@ obj-$(CONFIG_RDA_INTC)                      += irq-rda-intc.o
> >  obj-$(CONFIG_RENESAS_INTC_IRQPIN)    += irq-renesas-intc-irqpin.o
> >  obj-$(CONFIG_RENESAS_IRQC)           += irq-renesas-irqc.o
> >  obj-$(CONFIG_RENESAS_RZA1_IRQC)              += irq-renesas-rza1.o
> > +obj-$(CONFIG_RENESAS_RZG2L_IRQC)     += irq-renesas-rzg2l.o
> >  obj-$(CONFIG_VERSATILE_FPGA_IRQ)     += irq-versatile-fpga.o
> >  obj-$(CONFIG_ARCH_NSPIRE)            += irq-zevio.o
> >  obj-$(CONFIG_ARCH_VT8500)            += irq-vt8500.o
> > diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
> > new file mode 100644
> > index 000000000000..a846c6ee11d7
> > --- /dev/null
> > +++ b/drivers/irqchip/irq-renesas-rzg2l.c
> > @@ -0,0 +1,425 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Renesas RZ/G2L IRQC Driver
> > + *
> > + * Copyright (C) 2022 Renesas Electronics Corporation.
> > + *
> > + * Author: Lad Prabhakar <[e-mail]>
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/clk.h>
> > +#include <linux/err.h>
> > +#include <linux/io.h>
> > +#include <linux/irqchip.h>
> > +#include <linux/irqdomain.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/reset.h>
> > +#include <linux/spinlock.h>
> > +
> > +#define IRQC_IRQ_START                       1
> > +#define IRQC_IRQ_COUNT                       8
> > +#define IRQC_TINT_START                      (IRQC_IRQ_START + IRQC_IRQ_COUNT)
> > +#define IRQC_TINT_COUNT                      32
> > +#define IRQC_NUM_IRQ                 (IRQC_TINT_START + IRQC_TINT_COUNT)
> > +
> > +#define ISCR                         0x10
> > +#define IITSR                                0x14
> > +#define TSCR                         0x20
> > +#define TITSR0                               0x24
> > +#define TITSR1                               0x28
> > +#define TITSR0_MAX_INT                       16
> > +#define TITSEL_WIDTH                 0x2
> > +#define TSSR(n)                              (0x30 + ((n) * 4))
> > +#define TIEN                         BIT(7)
> > +#define TSSEL_SHIFT(n)                       (8 * (n))
> > +#define TSSEL_MASK                   GENMASK(7, 0)
> > +#define IRQ_MASK                     0x3
> > +
> > +#define TSSR_OFFSET(n)                       ((n) % 4)
> > +#define TSSR_INDEX(n)                        ((n) / 4)
> > +
> > +#define TITSR_TITSEL_EDGE_RISING     0
> > +#define TITSR_TITSEL_EDGE_FALLING    1
> > +#define TITSR_TITSEL_LEVEL_HIGH              2
> > +#define TITSR_TITSEL_LEVEL_LOW               3
> > +
> > +#define IITSR_IITSEL(n, sense)               ((sense) << ((n) * 2))
> > +#define IITSR_IITSEL_LEVEL_LOW               0
> > +#define IITSR_IITSEL_EDGE_FALLING    1
> > +#define IITSR_IITSEL_EDGE_RISING     2
> > +#define IITSR_IITSEL_EDGE_BOTH               3
> > +#define IITSR_IITSEL_MASK(n)         IITSR_IITSEL((n), 3)
> > +
> > +#define TINT_EXTRACT_HWIRQ(x)           FIELD_GET(GENMASK(15, 0), (x))
> > +#define TINT_EXTRACT_GPIOINT(x)         FIELD_GET(GENMASK(31, 16), (x))
> > +
> > +struct rzg2l_irqc_priv {
> > +     void __iomem *base;
> > +     struct of_phandle_args map[IRQC_NUM_IRQ];
> > +     raw_spinlock_t lock;
> > +};
> > +
> > +struct rzg2l_irqc_chip_data {
> > +     int tint;
> > +};
> > +
> > +static struct rzg2l_irqc_priv *irq_data_to_priv(struct irq_data *data)
> > +{
> > +     return data->domain->host_data;
> > +}
> > +
> > +static void rzg2l_irq_eoi(struct irq_data *d)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
> > +     struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +     u32 bit = BIT(hw_irq);
> > +     u32 reg;
> > +
> > +     reg = readl_relaxed(priv->base + ISCR);
> > +     if (reg & bit)
> > +             writel_relaxed(reg & ~bit, priv->base + ISCR);
> > +}
> > +
> > +static void rzg2l_tint_eoi(struct irq_data *d)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_TINT_START;
> > +     struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +     u32 bit = BIT(hw_irq);
> > +     u32 reg;
> > +
> > +     reg = readl_relaxed(priv->base + TSCR);
> > +     if (reg & bit)
> > +             writel_relaxed(reg & ~bit, priv->base + TSCR);
> > +}
> > +
> > +static void rzg2l_irqc_eoi(struct irq_data *d)
> > +{
> > +     struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +     unsigned int hw_irq = irqd_to_hwirq(d);
> > +
> > +     raw_spin_lock(&priv->lock);
> > +     if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
> > +             rzg2l_irq_eoi(d);
> > +     else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
> > +             rzg2l_tint_eoi(d);
> > +     raw_spin_unlock(&priv->lock);
> > +     irq_chip_eoi_parent(d);
> > +}
> > +
> > +static void rzg2l_irqc_irq_disable(struct irq_data *d)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d);
> > +
> > +     if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
> > +             struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +             u32 offset = hw_irq - IRQC_TINT_START;
> > +             u32 tssr_offset = TSSR_OFFSET(offset);
> > +             u8 tssr_index = TSSR_INDEX(offset);
> > +             u32 reg;
> > +
> > +             raw_spin_lock(&priv->lock);
> > +             reg = readl_relaxed(priv->base + TSSR(tssr_index));
> > +             reg &= ~(TSSEL_MASK << tssr_offset);
> > +             writel_relaxed(reg, priv->base + TSSR(tssr_index));
> > +             raw_spin_unlock(&priv->lock);
> > +     }
> > +     irq_chip_disable_parent(d);
> > +}
> > +
> > +static void rzg2l_irqc_irq_enable(struct irq_data *d)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d);
> > +
> > +     if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
> > +             struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +             unsigned long chip_data = *(unsigned long *)d->chip_data;
> > +             u32 offset = hw_irq - IRQC_TINT_START;
> > +             u32 tssr_offset = TSSR_OFFSET(offset);
> > +             u8 tssr_index = TSSR_INDEX(offset);
> > +             u32 reg;
> > +
> > +             raw_spin_lock(&priv->lock);
> > +             reg = readl_relaxed(priv->base + TSSR(tssr_index));
> > +             reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
> > +             writel_relaxed(reg, priv->base + TSSR(tssr_index));
> > +             raw_spin_unlock(&priv->lock);
> > +     }
> > +     irq_chip_enable_parent(d);
> > +}
> > +
> > +static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
> > +     struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +     u16 sense, tmp;
> > +
> > +     switch (type & IRQ_TYPE_SENSE_MASK) {
> > +     case IRQ_TYPE_LEVEL_LOW:
> > +             sense = IITSR_IITSEL_LEVEL_LOW;
> > +             break;
> > +
> > +     case IRQ_TYPE_EDGE_FALLING:
> > +             sense = IITSR_IITSEL_EDGE_FALLING;
> > +             break;
> > +
> > +     case IRQ_TYPE_EDGE_RISING:
> > +             sense = IITSR_IITSEL_EDGE_RISING;
> > +             break;
> > +
> > +     case IRQ_TYPE_EDGE_BOTH:
> > +             sense = IITSR_IITSEL_EDGE_BOTH;
> > +             break;
> > +
> > +     default:
> > +             return -EINVAL;
> > +     }
> > +
> > +     raw_spin_lock(&priv->lock);
> > +     tmp = readl_relaxed(priv->base + IITSR);
> > +     tmp &= ~IITSR_IITSEL_MASK(hw_irq);
> > +     tmp |= IITSR_IITSEL(hw_irq, sense);
> > +     writel_relaxed(tmp, priv->base + IITSR);
> > +     raw_spin_unlock(&priv->lock);
> > +
> > +     return 0;
> > +}
> > +
> > +static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
> > +{
> > +     struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> > +     unsigned int hwirq = irqd_to_hwirq(d);
> > +     u32 titseln = hwirq - IRQC_TINT_START;
> > +     u32 offset;
> > +     u8 sense;
> > +     u32 reg;
> > +
> > +     switch (type & IRQ_TYPE_SENSE_MASK) {
> > +     case IRQ_TYPE_EDGE_RISING:
> > +             sense = TITSR_TITSEL_EDGE_RISING;
> > +             break;
> > +
> > +     case IRQ_TYPE_EDGE_FALLING:
> > +             sense = TITSR_TITSEL_EDGE_FALLING;
> > +             break;
> > +
> > +     default:
> > +             return -EINVAL;
> > +     }
> > +
> > +     offset = TITSR0;
> > +     if (titseln >= TITSR0_MAX_INT) {
> > +             titseln -= TITSR0_MAX_INT;
> > +             offset = TITSR1;
> > +     }
> > +
> > +     raw_spin_lock(&priv->lock);
> > +     reg = readl_relaxed(priv->base + offset);
> > +     reg &= ~(IRQ_MASK << (titseln * TITSEL_WIDTH));
> > +     reg |= sense << (titseln * TITSEL_WIDTH);
> > +     writel_relaxed(reg, priv->base + offset);
> > +     raw_spin_unlock(&priv->lock);
> > +
> > +     return 0;
> > +}
> > +
> > +static int rzg2l_irqc_set_type(struct irq_data *d, unsigned int type)
> > +{
> > +     unsigned int hw_irq = irqd_to_hwirq(d);
> > +     int ret = -EINVAL;
> > +
> > +     if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
> > +             ret = rzg2l_irq_set_type(d, type);
> > +     else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
> > +             ret = rzg2l_tint_set_edge(d, type);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
> > +}
> > +
> > +static const struct irq_chip irqc_chip = {
> > +     .name                   = "rzg2l-irqc",
> > +     .irq_eoi                = rzg2l_irqc_eoi,
> > +     .irq_mask               = irq_chip_mask_parent,
> > +     .irq_unmask             = irq_chip_unmask_parent,
> > +     .irq_disable            = rzg2l_irqc_irq_disable,
> > +     .irq_enable             = rzg2l_irqc_irq_enable,
> > +     .irq_get_irqchip_state  = irq_chip_get_parent_state,
> > +     .irq_set_irqchip_state  = irq_chip_set_parent_state,
> > +     .irq_retrigger          = irq_chip_retrigger_hierarchy,
> > +     .irq_set_type           = rzg2l_irqc_set_type,
> > +     .flags                  = IRQCHIP_MASK_ON_SUSPEND |
> > +                               IRQCHIP_SET_TYPE_MASKED |
> > +                               IRQCHIP_SKIP_SET_WAKE,
> > +};
> > +
> > +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> > +                         unsigned int nr_irqs, void *arg)
> > +{
> > +     struct rzg2l_irqc_priv *priv = domain->host_data;
> > +     unsigned long *chip_data = NULL;
>
> Why the init to NULL?
>
Can be dropped.

> > +     struct irq_fwspec spec;
> > +     irq_hw_number_t hwirq;
> > +     int tint = -EINVAL;
> > +     unsigned int type;
> > +     unsigned int i;
> > +     int ret;
> > +
> > +     ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /*
> > +      * For TINT interrupts ie where pinctrl driver is child of irqc domain
> > +      * the hwirq and TINT are encoded in fwspec->param[0].
> > +      * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> > +      * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> > +      * in IRQC registers to enable a given gpio pin as interrupt.
> > +      */
> > +     if (hwirq > IRQC_IRQ_COUNT) {
> > +             tint = TINT_EXTRACT_GPIOINT(hwirq);
> > +             hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> > +
> > +             if (hwirq < IRQC_TINT_START)
> > +                     return -EINVAL;
> > +     }
> > +
> > +     if (hwirq > (IRQC_NUM_IRQ - 1))
> > +             return -EINVAL;
> > +
> > +     chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
>
> Are we really allocating an unsigned long for something that already
> fits in something that is pointer-sized?
>
I think I received some feedback to use unsigned long.  Let me know
what you want me to use here.

> > +     if (!chip_data)
> > +             return -ENOMEM;
> > +     *chip_data = tint;
>
> So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
> This can't be right.
>
Yes *chip_data can be -EINVAL. IRQC block handles IRQ0-7 and
GPIOINT0-122. So the -EINVAL here is for IRQ0-7 case were dont
required the chip data in the call backs hence -EINVAL, Whereas for
GPIOINT0-122 we need chip_data in the callbacks as this value needs to
be programmed in the hardware registers.

> > +
> > +     ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
> > +                                         chip_data);
> > +     if (ret) {
> > +             kfree(chip_data);
> > +             return ret;
> > +     }
> > +
> > +     spec.fwnode = domain->parent->fwnode;
> > +     spec.param_count = priv->map[hwirq].args_count;
> > +     for (i = 0; i < spec.param_count; i++)
> > +             spec.param[i] = priv->map[hwirq].args[i];
>
> Why isn't that simply:
>
>         spec = priv->map[hwirq];
>
spec is of type ‘struct irq_fwspec’ and map is of type ‘struct of_phandle_args’.

> as this really is the interrupt you want to map to?
>
Yes.

> > +
> > +     ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);
>
> or even better:
>
>         ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
>                                            &priv->map[hwirq]);
>
Does not work as map is of type ‘struct of_phandle_args’.

> > +     if (ret)
> > +             kfree(chip_data);
> > +
> > +     return ret;
> > +}
> > +
> > +static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
> > +                                unsigned int nr_irqs)
> > +{
> > +     struct irq_data *d;
> > +
> > +     d = irq_domain_get_irq_data(domain, virq);
> > +     if (d)
> > +             kfree(d->chip_data);
> > +
> > +     irq_domain_free_irqs_common(domain, virq, nr_irqs);
> > +}
> > +
> > +static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
> > +     .alloc = rzg2l_irqc_alloc,
> > +     .free = rzg2l_irqc_domain_free,
> > +     .translate = irq_domain_translate_twocell,
> > +};
> > +
> > +static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
> > +                             struct device_node *np)
> > +{
> > +     unsigned int i;
> > +     int ret;
> > +
> > +     for (i = 0; i < IRQC_NUM_IRQ; i++) {
> > +             ret = of_irq_parse_one(np, i, &priv->map[i]);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
> > +{
> > +     struct irq_domain *irq_domain, *parent_domain;
> > +     struct platform_device *pdev;
> > +     struct reset_control *resetn;
> > +     struct rzg2l_irqc_priv *priv;
> > +     int ret;
> > +
> > +     pdev = of_find_device_by_node(node);
> > +     if (!pdev)
> > +             return -ENODEV;
> > +
> > +     parent_domain = irq_find_host(parent);
> > +     if (!parent_domain) {
> > +             dev_err(&pdev->dev, "cannot find parent domain\n");
> > +             return -ENODEV;
> > +     }
> > +
> > +     priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > +     if (!priv)
> > +             return -ENOMEM;
> > +
> > +     priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
> > +     if (IS_ERR(priv->base))
> > +             return PTR_ERR(priv->base);
> > +
> > +     ret = rzg2l_irqc_parse_map(priv, node);
> > +     if (ret) {
> > +             dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
> > +             return ret;
> > +     }
> > +
> > +     resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);
> > +     if (IS_ERR(resetn))
> > +             return IS_ERR(resetn);
> > +
> > +     ret = reset_control_deassert(resetn);
> > +     if (ret) {
> > +             dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
> > +             return ret;
> > +     }
> > +
> > +     pm_runtime_enable(&pdev->dev);
> > +     ret = pm_runtime_resume_and_get(&pdev->dev);
> > +     if (ret < 0) {
> > +             dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
> > +             goto pm_disable;
> > +     }
>
> If using runtime PM, why isn't the core IRQ code made aware of this
> dependency by registering the device with irq_domain_set_pm_device()
> instead of leaving it enabled forever?
>
Ouch will add irq_domain_set_pm_device() below.

Cheers,
Prabhakar

Marc Zyngier June 25, 2022, 12:08 p.m. UTC | #3

On Sat, 25 Jun 2022 11:54:44 +0100,
"Lad, Prabhakar" <[e-mail]> wrote:
> 
> Hi Marc,
> 
> Thank you for the review.
> 
> On Sat, Jun 25, 2022 at 10:30 AM Marc Zyngier <[e-mail]> wrote:
> >
> > On Mon, 23 May 2022 18:42:35 +0100,
> > Lad Prabhakar <[e-mail]> wrote:
> > >

[...]

> > > +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> > > +                         unsigned int nr_irqs, void *arg)
> > > +{
> > > +     struct rzg2l_irqc_priv *priv = domain->host_data;
> > > +     unsigned long *chip_data = NULL;
> >
> > Why the init to NULL?
> >
> Can be dropped.
> 
> > > +     struct irq_fwspec spec;
> > > +     irq_hw_number_t hwirq;
> > > +     int tint = -EINVAL;
> > > +     unsigned int type;
> > > +     unsigned int i;
> > > +     int ret;
> > > +
> > > +     ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     /*
> > > +      * For TINT interrupts ie where pinctrl driver is child of irqc domain
> > > +      * the hwirq and TINT are encoded in fwspec->param[0].
> > > +      * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> > > +      * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> > > +      * in IRQC registers to enable a given gpio pin as interrupt.
> > > +      */
> > > +     if (hwirq > IRQC_IRQ_COUNT) {
> > > +             tint = TINT_EXTRACT_GPIOINT(hwirq);
> > > +             hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> > > +
> > > +             if (hwirq < IRQC_TINT_START)
> > > +                     return -EINVAL;
> > > +     }
> > > +
> > > +     if (hwirq > (IRQC_NUM_IRQ - 1))
> > > +             return -EINVAL;
> > > +
> > > +     chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
> >
> > Are we really allocating an unsigned long for something that already
> > fits in something that is pointer-sized?
> >
> I think I received some feedback to use unsigned long.  Let me know
> what you want me to use here.

I think this is just a waste of memory, but I don't really care.

> 
> > > +     if (!chip_data)
> > > +             return -ENOMEM;
> > > +     *chip_data = tint;
> >
> > So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
> > This can't be right.
> >
> Yes *chip_data can be -EINVAL. IRQC block handles IRQ0-7 and
> GPIOINT0-122. So the -EINVAL here is for IRQ0-7 case were dont
> required the chip data in the call backs hence -EINVAL, Whereas for
> GPIOINT0-122 we need chip_data in the callbacks as this value needs to
> be programmed in the hardware registers.

I can't see anything that checks it (let alone the difference in
types). And if it isn't checked, this means that the allocation is
pointless.

> 
> > > +
> > > +     ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
> > > +                                         chip_data);
> > > +     if (ret) {
> > > +             kfree(chip_data);
> > > +             return ret;
> > > +     }
> > > +
> > > +     spec.fwnode = domain->parent->fwnode;
> > > +     spec.param_count = priv->map[hwirq].args_count;
> > > +     for (i = 0; i < spec.param_count; i++)
> > > +             spec.param[i] = priv->map[hwirq].args[i];
> >
> > Why isn't that simply:
> >
> >         spec = priv->map[hwirq];
> >
> spec is of type ‘struct irq_fwspec’ and map is of type ‘struct of_phandle_args’.
> 
> > as this really is the interrupt you want to map to?
> >
> Yes.
> 
> > > +
> > > +     ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);
> >
> > or even better:
> >
> >         ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
> >                                            &priv->map[hwirq]);
> >
> Does not work as map is of type ‘struct of_phandle_args’.

Which begs the question: why don't you convert it to an irq_fwspec the
first place and be done with it?

> 
> > > +     if (ret)
> > > +             kfree(chip_data);
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
> > > +                                unsigned int nr_irqs)
> > > +{
> > > +     struct irq_data *d;
> > > +
> > > +     d = irq_domain_get_irq_data(domain, virq);
> > > +     if (d)
> > > +             kfree(d->chip_data);
> > > +
> > > +     irq_domain_free_irqs_common(domain, virq, nr_irqs);
> > > +}
> > > +
> > > +static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
> > > +     .alloc = rzg2l_irqc_alloc,
> > > +     .free = rzg2l_irqc_domain_free,
> > > +     .translate = irq_domain_translate_twocell,
> > > +};
> > > +
> > > +static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
> > > +                             struct device_node *np)

nit: this function could afford being renamed to something more
correct. It really doesn't map anything, only retrieves the output
interrupts.

> > > +{
> > > +     unsigned int i;
> > > +     int ret;
> > > +
> > > +     for (i = 0; i < IRQC_NUM_IRQ; i++) {
> > > +             ret = of_irq_parse_one(np, i, &priv->map[i]);

Make map an array of irq_fwspec, and use of_phandle_args_to_fwspec()
for the conversion.

> > > +             if (ret)
> > > +                     return ret;
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
> > > +{
> > > +     struct irq_domain *irq_domain, *parent_domain;
> > > +     struct platform_device *pdev;
> > > +     struct reset_control *resetn;
> > > +     struct rzg2l_irqc_priv *priv;
> > > +     int ret;
> > > +
> > > +     pdev = of_find_device_by_node(node);
> > > +     if (!pdev)
> > > +             return -ENODEV;
> > > +
> > > +     parent_domain = irq_find_host(parent);
> > > +     if (!parent_domain) {
> > > +             dev_err(&pdev->dev, "cannot find parent domain\n");
> > > +             return -ENODEV;
> > > +     }
> > > +
> > > +     priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > > +     if (!priv)
> > > +             return -ENOMEM;
> > > +
> > > +     priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
> > > +     if (IS_ERR(priv->base))
> > > +             return PTR_ERR(priv->base);
> > > +
> > > +     ret = rzg2l_irqc_parse_map(priv, node);
> > > +     if (ret) {
> > > +             dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
> > > +             return ret;
> > > +     }
> > > +
> > > +     resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);
> > > +     if (IS_ERR(resetn))
> > > +             return IS_ERR(resetn);
> > > +
> > > +     ret = reset_control_deassert(resetn);
> > > +     if (ret) {
> > > +             dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
> > > +             return ret;
> > > +     }
> > > +
> > > +     pm_runtime_enable(&pdev->dev);
> > > +     ret = pm_runtime_resume_and_get(&pdev->dev);
> > > +     if (ret < 0) {
> > > +             dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
> > > +             goto pm_disable;
> > > +     }
> >
> > If using runtime PM, why isn't the core IRQ code made aware of this
> > dependency by registering the device with irq_domain_set_pm_device()
> > instead of leaving it enabled forever?
> >
> Ouch will add irq_domain_set_pm_device() below.

You'll need a bit more than that. You'll either need to take a PM
reference on each alloc, or improve irq_chip_pm_{get,put}() to talk
the hierarchy.

That's probably a separate patch.

	M.

Lad, Prabhakar June 25, 2022, 12:48 p.m. UTC | #4

Hi Marc,

On Sat, Jun 25, 2022 at 1:08 PM Marc Zyngier <[e-mail]> wrote:
>
> On Sat, 25 Jun 2022 11:54:44 +0100,
> "Lad, Prabhakar" <[e-mail]> wrote:
> >
> > Hi Marc,
> >
> > Thank you for the review.
> >
> > On Sat, Jun 25, 2022 at 10:30 AM Marc Zyngier <[e-mail]> wrote:
> > >
> > > On Mon, 23 May 2022 18:42:35 +0100,
> > > Lad Prabhakar <[e-mail]> wrote:
> > > >
>
> [...]
>
> > > > +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> > > > +                         unsigned int nr_irqs, void *arg)
> > > > +{
> > > > +     struct rzg2l_irqc_priv *priv = domain->host_data;
> > > > +     unsigned long *chip_data = NULL;
> > >
> > > Why the init to NULL?
> > >
> > Can be dropped.
> >
> > > > +     struct irq_fwspec spec;
> > > > +     irq_hw_number_t hwirq;
> > > > +     int tint = -EINVAL;
> > > > +     unsigned int type;
> > > > +     unsigned int i;
> > > > +     int ret;
> > > > +
> > > > +     ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     /*
> > > > +      * For TINT interrupts ie where pinctrl driver is child of irqc domain
> > > > +      * the hwirq and TINT are encoded in fwspec->param[0].
> > > > +      * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> > > > +      * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> > > > +      * in IRQC registers to enable a given gpio pin as interrupt.
> > > > +      */
> > > > +     if (hwirq > IRQC_IRQ_COUNT) {
> > > > +             tint = TINT_EXTRACT_GPIOINT(hwirq);
> > > > +             hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> > > > +
> > > > +             if (hwirq < IRQC_TINT_START)
> > > > +                     return -EINVAL;
> > > > +     }
> > > > +
> > > > +     if (hwirq > (IRQC_NUM_IRQ - 1))
> > > > +             return -EINVAL;
> > > > +
> > > > +     chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
> > >
> > > Are we really allocating an unsigned long for something that already
> > > fits in something that is pointer-sized?
> > >
> > I think I received some feedback to use unsigned long.  Let me know
> > what you want me to use here.
>
> I think this is just a waste of memory, but I don't really care.
>
Is there any better way I can handle it?

> >
> > > > +     if (!chip_data)
> > > > +             return -ENOMEM;
> > > > +     *chip_data = tint;
> > >
> > > So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
> > > This can't be right.
> > >
> > Yes *chip_data can be -EINVAL. IRQC block handles IRQ0-7 and
> > GPIOINT0-122. So the -EINVAL here is for IRQ0-7 case were dont
> > required the chip data in the call backs hence -EINVAL, Whereas for
> > GPIOINT0-122 we need chip_data in the callbacks as this value needs to
> > be programmed in the hardware registers.
>
> I can't see anything that checks it (let alone the difference in
> types). And if it isn't checked, this means that the allocation is
> pointless.
>
There are checks for example below:

static void rzg2l_irqc_irq_enable(struct irq_data *d)
{
    unsigned int hw_irq = irqd_to_hwirq(d);

    if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
        struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
        unsigned long chip_data = *(unsigned long *)d->chip_data;
        u32 offset = hw_irq - IRQC_TINT_START;
        u32 tssr_offset = TSSR_OFFSET(offset);
        u8 tssr_index = TSSR_INDEX(offset);
        u32 reg;

        raw_spin_lock(&priv->lock);
        reg = readl_relaxed(priv->base + TSSR(tssr_index));
        reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
        writel_relaxed(reg, priv->base + TSSR(tssr_index));
        raw_spin_unlock(&priv->lock);
    }
    irq_chip_enable_parent(d);
}

This check hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ here
would mean its GPIOINT0-122 and then the chip data will be used.

> >
> > > > +
> > > > +     ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
> > > > +                                         chip_data);
> > > > +     if (ret) {
> > > > +             kfree(chip_data);
> > > > +             return ret;
> > > > +     }
> > > > +
> > > > +     spec.fwnode = domain->parent->fwnode;
> > > > +     spec.param_count = priv->map[hwirq].args_count;
> > > > +     for (i = 0; i < spec.param_count; i++)
> > > > +             spec.param[i] = priv->map[hwirq].args[i];
> > >
> > > Why isn't that simply:
> > >
> > >         spec = priv->map[hwirq];
> > >
> > spec is of type ‘struct irq_fwspec’ and map is of type ‘struct of_phandle_args’.
> >
> > > as this really is the interrupt you want to map to?
> > >
> > Yes.
> >
> > > > +
> > > > +     ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);
> > >
> > > or even better:
> > >
> > >         ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
> > >                                            &priv->map[hwirq]);
> > >
> > Does not work as map is of type ‘struct of_phandle_args’.
>
> Which begs the question: why don't you convert it to an irq_fwspec the
> first place and be done with it?
>
Right..
> >
> > > > +     if (ret)
> > > > +             kfree(chip_data);
> > > > +
> > > > +     return ret;
> > > > +}
> > > > +
> > > > +static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
> > > > +                                unsigned int nr_irqs)
> > > > +{
> > > > +     struct irq_data *d;
> > > > +
> > > > +     d = irq_domain_get_irq_data(domain, virq);
> > > > +     if (d)
> > > > +             kfree(d->chip_data);
> > > > +
> > > > +     irq_domain_free_irqs_common(domain, virq, nr_irqs);
> > > > +}
> > > > +
> > > > +static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
> > > > +     .alloc = rzg2l_irqc_alloc,
> > > > +     .free = rzg2l_irqc_domain_free,
> > > > +     .translate = irq_domain_translate_twocell,
> > > > +};
> > > > +
> > > > +static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
> > > > +                             struct device_node *np)
>
> nit: this function could afford being renamed to something more
> correct. It really doesn't map anything, only retrieves the output
> interrupts.
>
Sure will do.

> > > > +{
> > > > +     unsigned int i;
> > > > +     int ret;
> > > > +
> > > > +     for (i = 0; i < IRQC_NUM_IRQ; i++) {
> > > > +             ret = of_irq_parse_one(np, i, &priv->map[i]);
>
> Make map an array of irq_fwspec, and use of_phandle_args_to_fwspec()
> for the conversion.
>
... Good point, will do.

> > > > +             if (ret)
> > > > +                     return ret;
> > > > +     }
> > > > +
> > > > +     return 0;
> > > > +}
> > > > +
> > > > +static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
> > > > +{
> > > > +     struct irq_domain *irq_domain, *parent_domain;
> > > > +     struct platform_device *pdev;
> > > > +     struct reset_control *resetn;
> > > > +     struct rzg2l_irqc_priv *priv;
> > > > +     int ret;
> > > > +
> > > > +     pdev = of_find_device_by_node(node);
> > > > +     if (!pdev)
> > > > +             return -ENODEV;
> > > > +
> > > > +     parent_domain = irq_find_host(parent);
> > > > +     if (!parent_domain) {
> > > > +             dev_err(&pdev->dev, "cannot find parent domain\n");
> > > > +             return -ENODEV;
> > > > +     }
> > > > +
> > > > +     priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > > > +     if (!priv)
> > > > +             return -ENOMEM;
> > > > +
> > > > +     priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
> > > > +     if (IS_ERR(priv->base))
> > > > +             return PTR_ERR(priv->base);
> > > > +
> > > > +     ret = rzg2l_irqc_parse_map(priv, node);
> > > > +     if (ret) {
> > > > +             dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
> > > > +             return ret;
> > > > +     }
> > > > +
> > > > +     resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);
> > > > +     if (IS_ERR(resetn))
> > > > +             return IS_ERR(resetn);
> > > > +
> > > > +     ret = reset_control_deassert(resetn);
> > > > +     if (ret) {
> > > > +             dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
> > > > +             return ret;
> > > > +     }
> > > > +
> > > > +     pm_runtime_enable(&pdev->dev);
> > > > +     ret = pm_runtime_resume_and_get(&pdev->dev);
> > > > +     if (ret < 0) {
> > > > +             dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
> > > > +             goto pm_disable;
> > > > +     }
> > >
> > > If using runtime PM, why isn't the core IRQ code made aware of this
> > > dependency by registering the device with irq_domain_set_pm_device()
> > > instead of leaving it enabled forever?
> > >
> > Ouch will add irq_domain_set_pm_device() below.
>
> You'll need a bit more than that. You'll either need to take a PM
> reference on each alloc, or improve irq_chip_pm_{get,put}() to talk
> the hierarchy.
>
Aha I see.

> That's probably a separate patch.
>
Agreed will make it a separate patch, once the driver gets in.


Cheers,
Prabhakar

Marc Zyngier June 25, 2022, 4:09 p.m. UTC | #5

On Sat, 25 Jun 2022 13:48:08 +0100,
"Lad, Prabhakar" <[e-mail]> wrote:
> 
> Hi Marc,
> 
> On Sat, Jun 25, 2022 at 1:08 PM Marc Zyngier <[e-mail]> wrote:
> >
> > On Sat, 25 Jun 2022 11:54:44 +0100,
> > "Lad, Prabhakar" <[e-mail]> wrote:
> > >
> > > Hi Marc,
> > >
> > > Thank you for the review.
> > >
> > > On Sat, Jun 25, 2022 at 10:30 AM Marc Zyngier <[e-mail]> wrote:
> > > >
> > > > On Mon, 23 May 2022 18:42:35 +0100,
> > > > Lad Prabhakar <[e-mail]> wrote:
> > > > >
> >
> > [...]
> >
> > > > > +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> > > > > +                         unsigned int nr_irqs, void *arg)
> > > > > +{
> > > > > +     struct rzg2l_irqc_priv *priv = domain->host_data;
> > > > > +     unsigned long *chip_data = NULL;
> > > >
> > > > Why the init to NULL?
> > > >
> > > Can be dropped.
> > >
> > > > > +     struct irq_fwspec spec;
> > > > > +     irq_hw_number_t hwirq;
> > > > > +     int tint = -EINVAL;
> > > > > +     unsigned int type;
> > > > > +     unsigned int i;
> > > > > +     int ret;
> > > > > +
> > > > > +     ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> > > > > +     if (ret)
> > > > > +             return ret;
> > > > > +
> > > > > +     /*
> > > > > +      * For TINT interrupts ie where pinctrl driver is child of irqc domain
> > > > > +      * the hwirq and TINT are encoded in fwspec->param[0].
> > > > > +      * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> > > > > +      * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> > > > > +      * in IRQC registers to enable a given gpio pin as interrupt.
> > > > > +      */
> > > > > +     if (hwirq > IRQC_IRQ_COUNT) {
> > > > > +             tint = TINT_EXTRACT_GPIOINT(hwirq);
> > > > > +             hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> > > > > +
> > > > > +             if (hwirq < IRQC_TINT_START)
> > > > > +                     return -EINVAL;
> > > > > +     }
> > > > > +
> > > > > +     if (hwirq > (IRQC_NUM_IRQ - 1))
> > > > > +             return -EINVAL;
> > > > > +
> > > > > +     chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
> > > >
> > > > Are we really allocating an unsigned long for something that already
> > > > fits in something that is pointer-sized?
> > > >
> > > I think I received some feedback to use unsigned long.  Let me know
> > > what you want me to use here.
> >
> > I think this is just a waste of memory, but I don't really care.
> >
> Is there any better way I can handle it?

How about (shock, horror) a cast?

> 
> > >
> > > > > +     if (!chip_data)
> > > > > +             return -ENOMEM;
> > > > > +     *chip_data = tint;
> > > >
> > > > So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
> > > > This can't be right.
> > > >
> > > Yes *chip_data can be -EINVAL. IRQC block handles IRQ0-7 and
> > > GPIOINT0-122. So the -EINVAL here is for IRQ0-7 case were dont
> > > required the chip data in the call backs hence -EINVAL, Whereas for
> > > GPIOINT0-122 we need chip_data in the callbacks as this value needs to
> > > be programmed in the hardware registers.
> >
> > I can't see anything that checks it (let alone the difference in
> > types). And if it isn't checked, this means that the allocation is
> > pointless.
> >
> There are checks for example below:
> 
> static void rzg2l_irqc_irq_enable(struct irq_data *d)
> {
>     unsigned int hw_irq = irqd_to_hwirq(d);
> 
>     if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
>         struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
>         unsigned long chip_data = *(unsigned long *)d->chip_data;
>         u32 offset = hw_irq - IRQC_TINT_START;
>         u32 tssr_offset = TSSR_OFFSET(offset);
>         u8 tssr_index = TSSR_INDEX(offset);
>         u32 reg;
> 
>         raw_spin_lock(&priv->lock);
>         reg = readl_relaxed(priv->base + TSSR(tssr_index));
>         reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
>         writel_relaxed(reg, priv->base + TSSR(tssr_index));
>         raw_spin_unlock(&priv->lock);
>     }
>     irq_chip_enable_parent(d);
> }
> 
> This check hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ here
> would mean its GPIOINT0-122 and then the chip data will be used.

That doesn't check the content of chip_data if outside of this
condition. Nonetheless, you allocate an unsigned long to store
-EINVAL. Not only this is a pointless allocation, but you use it to
store something that you never retrieve the first place. Don't you see
the problem?

	M.

Lad, Prabhakar June 25, 2022, 7:26 p.m. UTC | #6

Hi Marc,

On Sat, Jun 25, 2022 at 5:09 PM Marc Zyngier <[e-mail]> wrote:
>
> On Sat, 25 Jun 2022 13:48:08 +0100,
> "Lad, Prabhakar" <[e-mail]> wrote:
> >
> > Hi Marc,
> >
> > On Sat, Jun 25, 2022 at 1:08 PM Marc Zyngier <[e-mail]> wrote:
> > >
> > > On Sat, 25 Jun 2022 11:54:44 +0100,
> > > "Lad, Prabhakar" <[e-mail]> wrote:
> > > >
> > > > Hi Marc,
> > > >
> > > > Thank you for the review.
> > > >
> > > > On Sat, Jun 25, 2022 at 10:30 AM Marc Zyngier <[e-mail]> wrote:
> > > > >
> > > > > On Mon, 23 May 2022 18:42:35 +0100,
> > > > > Lad Prabhakar <[e-mail]> wrote:
> > > > > >
> > >
> > > [...]
> > >
> > > > > > +static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
> > > > > > +                         unsigned int nr_irqs, void *arg)
> > > > > > +{
> > > > > > +     struct rzg2l_irqc_priv *priv = domain->host_data;
> > > > > > +     unsigned long *chip_data = NULL;
> > > > >
> > > > > Why the init to NULL?
> > > > >
> > > > Can be dropped.
> > > >
> > > > > > +     struct irq_fwspec spec;
> > > > > > +     irq_hw_number_t hwirq;
> > > > > > +     int tint = -EINVAL;
> > > > > > +     unsigned int type;
> > > > > > +     unsigned int i;
> > > > > > +     int ret;
> > > > > > +
> > > > > > +     ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
> > > > > > +     if (ret)
> > > > > > +             return ret;
> > > > > > +
> > > > > > +     /*
> > > > > > +      * For TINT interrupts ie where pinctrl driver is child of irqc domain
> > > > > > +      * the hwirq and TINT are encoded in fwspec->param[0].
> > > > > > +      * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
> > > > > > +      * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
> > > > > > +      * in IRQC registers to enable a given gpio pin as interrupt.
> > > > > > +      */
> > > > > > +     if (hwirq > IRQC_IRQ_COUNT) {
> > > > > > +             tint = TINT_EXTRACT_GPIOINT(hwirq);
> > > > > > +             hwirq = TINT_EXTRACT_HWIRQ(hwirq);
> > > > > > +
> > > > > > +             if (hwirq < IRQC_TINT_START)
> > > > > > +                     return -EINVAL;
> > > > > > +     }
> > > > > > +
> > > > > > +     if (hwirq > (IRQC_NUM_IRQ - 1))
> > > > > > +             return -EINVAL;
> > > > > > +
> > > > > > +     chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
> > > > >
> > > > > Are we really allocating an unsigned long for something that already
> > > > > fits in something that is pointer-sized?
> > > > >
> > > > I think I received some feedback to use unsigned long.  Let me know
> > > > what you want me to use here.
> > >
> > > I think this is just a waste of memory, but I don't really care.
> > >
> > Is there any better way I can handle it?
>
> How about (shock, horror) a cast?
>
Right I get you now..

> >
> > > >
> > > > > > +     if (!chip_data)
> > > > > > +             return -ENOMEM;
> > > > > > +     *chip_data = tint;
> > > > >
> > > > > So here, *chip_data can be set to -EINVAL if hwirq <= IRQC_IRQ_COUNT?
> > > > > This can't be right.
> > > > >
> > > > Yes *chip_data can be -EINVAL. IRQC block handles IRQ0-7 and
> > > > GPIOINT0-122. So the -EINVAL here is for IRQ0-7 case were dont
> > > > required the chip data in the call backs hence -EINVAL, Whereas for
> > > > GPIOINT0-122 we need chip_data in the callbacks as this value needs to
> > > > be programmed in the hardware registers.
> > >
> > > I can't see anything that checks it (let alone the difference in
> > > types). And if it isn't checked, this means that the allocation is
> > > pointless.
> > >
> > There are checks for example below:
> >
> > static void rzg2l_irqc_irq_enable(struct irq_data *d)
> > {
> >     unsigned int hw_irq = irqd_to_hwirq(d);
> >
> >     if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
> >         struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
> >         unsigned long chip_data = *(unsigned long *)d->chip_data;
> >         u32 offset = hw_irq - IRQC_TINT_START;
> >         u32 tssr_offset = TSSR_OFFSET(offset);
> >         u8 tssr_index = TSSR_INDEX(offset);
> >         u32 reg;
> >
> >         raw_spin_lock(&priv->lock);
> >         reg = readl_relaxed(priv->base + TSSR(tssr_index));
> >         reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
> >         writel_relaxed(reg, priv->base + TSSR(tssr_index));
> >         raw_spin_unlock(&priv->lock);
> >     }
> >     irq_chip_enable_parent(d);
> > }
> >
> > This check hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ here
> > would mean its GPIOINT0-122 and then the chip data will be used.
>
> That doesn't check the content of chip_data if outside of this
> condition. Nonetheless, you allocate an unsigned long to store
> -EINVAL. Not only this is a pointless allocation, but you use it to
> store something that you never retrieve the first place. Don't you see
> the problem?
>
... and when using cast I no longer need the allocation.

Cheers,
Prabhakar

Patch

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 15edb9a6fcae..f3d071422f3b 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -242,6 +242,14 @@  config RENESAS_RZA1_IRQC
 	  Enable support for the Renesas RZ/A1 Interrupt Controller, to use up
 	  to 8 external interrupts with configurable sense select.
 
+config RENESAS_RZG2L_IRQC
+	bool "Renesas RZ/G2L (and alike SoC) IRQC support" if COMPILE_TEST
+	select GENERIC_IRQ_CHIP
+	select IRQ_DOMAIN_HIERARCHY
+	help
+	  Enable support for the Renesas RZ/G2L (and alike SoC) Interrupt Controller
+	  for external devices.
+
 config SL28CPLD_INTC
 	bool "Kontron sl28cpld IRQ controller"
 	depends on MFD_SL28CPLD=y || COMPILE_TEST
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 160a1d8ceaa9..eaa56eec2b23 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -51,6 +51,7 @@  obj-$(CONFIG_RDA_INTC)			+= irq-rda-intc.o
 obj-$(CONFIG_RENESAS_INTC_IRQPIN)	+= irq-renesas-intc-irqpin.o
 obj-$(CONFIG_RENESAS_IRQC)		+= irq-renesas-irqc.o
 obj-$(CONFIG_RENESAS_RZA1_IRQC)		+= irq-renesas-rza1.o
+obj-$(CONFIG_RENESAS_RZG2L_IRQC)	+= irq-renesas-rzg2l.o
 obj-$(CONFIG_VERSATILE_FPGA_IRQ)	+= irq-versatile-fpga.o
 obj-$(CONFIG_ARCH_NSPIRE)		+= irq-zevio.o
 obj-$(CONFIG_ARCH_VT8500)		+= irq-vt8500.o
diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
new file mode 100644
index 000000000000..a846c6ee11d7
--- /dev/null
+++ b/drivers/irqchip/irq-renesas-rzg2l.c
@@ -0,0 +1,425 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/G2L IRQC Driver
+ *
+ * Copyright (C) 2022 Renesas Electronics Corporation.
+ *
+ * Author: Lad Prabhakar <[e-mail]>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <linux/spinlock.h>
+
+#define IRQC_IRQ_START			1
+#define IRQC_IRQ_COUNT			8
+#define IRQC_TINT_START			(IRQC_IRQ_START + IRQC_IRQ_COUNT)
+#define IRQC_TINT_COUNT			32
+#define IRQC_NUM_IRQ			(IRQC_TINT_START + IRQC_TINT_COUNT)
+
+#define ISCR				0x10
+#define IITSR				0x14
+#define TSCR				0x20
+#define TITSR0				0x24
+#define TITSR1				0x28
+#define TITSR0_MAX_INT			16
+#define TITSEL_WIDTH			0x2
+#define TSSR(n)				(0x30 + ((n) * 4))
+#define TIEN				BIT(7)
+#define TSSEL_SHIFT(n)			(8 * (n))
+#define TSSEL_MASK			GENMASK(7, 0)
+#define IRQ_MASK			0x3
+
+#define TSSR_OFFSET(n)			((n) % 4)
+#define TSSR_INDEX(n)			((n) / 4)
+
+#define TITSR_TITSEL_EDGE_RISING	0
+#define TITSR_TITSEL_EDGE_FALLING	1
+#define TITSR_TITSEL_LEVEL_HIGH		2
+#define TITSR_TITSEL_LEVEL_LOW		3
+
+#define IITSR_IITSEL(n, sense)		((sense) << ((n) * 2))
+#define IITSR_IITSEL_LEVEL_LOW		0
+#define IITSR_IITSEL_EDGE_FALLING	1
+#define IITSR_IITSEL_EDGE_RISING	2
+#define IITSR_IITSEL_EDGE_BOTH		3
+#define IITSR_IITSEL_MASK(n)		IITSR_IITSEL((n), 3)
+
+#define TINT_EXTRACT_HWIRQ(x)           FIELD_GET(GENMASK(15, 0), (x))
+#define TINT_EXTRACT_GPIOINT(x)         FIELD_GET(GENMASK(31, 16), (x))
+
+struct rzg2l_irqc_priv {
+	void __iomem *base;
+	struct of_phandle_args map[IRQC_NUM_IRQ];
+	raw_spinlock_t lock;
+};
+
+struct rzg2l_irqc_chip_data {
+	int tint;
+};
+
+static struct rzg2l_irqc_priv *irq_data_to_priv(struct irq_data *data)
+{
+	return data->domain->host_data;
+}
+
+static void rzg2l_irq_eoi(struct irq_data *d)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
+	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	u32 bit = BIT(hw_irq);
+	u32 reg;
+
+	reg = readl_relaxed(priv->base + ISCR);
+	if (reg & bit)
+		writel_relaxed(reg & ~bit, priv->base + ISCR);
+}
+
+static void rzg2l_tint_eoi(struct irq_data *d)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_TINT_START;
+	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	u32 bit = BIT(hw_irq);
+	u32 reg;
+
+	reg = readl_relaxed(priv->base + TSCR);
+	if (reg & bit)
+		writel_relaxed(reg & ~bit, priv->base + TSCR);
+}
+
+static void rzg2l_irqc_eoi(struct irq_data *d)
+{
+	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	unsigned int hw_irq = irqd_to_hwirq(d);
+
+	raw_spin_lock(&priv->lock);
+	if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
+		rzg2l_irq_eoi(d);
+	else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
+		rzg2l_tint_eoi(d);
+	raw_spin_unlock(&priv->lock);
+	irq_chip_eoi_parent(d);
+}
+
+static void rzg2l_irqc_irq_disable(struct irq_data *d)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d);
+
+	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
+		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+		u32 offset = hw_irq - IRQC_TINT_START;
+		u32 tssr_offset = TSSR_OFFSET(offset);
+		u8 tssr_index = TSSR_INDEX(offset);
+		u32 reg;
+
+		raw_spin_lock(&priv->lock);
+		reg = readl_relaxed(priv->base + TSSR(tssr_index));
+		reg &= ~(TSSEL_MASK << tssr_offset);
+		writel_relaxed(reg, priv->base + TSSR(tssr_index));
+		raw_spin_unlock(&priv->lock);
+	}
+	irq_chip_disable_parent(d);
+}
+
+static void rzg2l_irqc_irq_enable(struct irq_data *d)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d);
+
+	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
+		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+		unsigned long chip_data = *(unsigned long *)d->chip_data;
+		u32 offset = hw_irq - IRQC_TINT_START;
+		u32 tssr_offset = TSSR_OFFSET(offset);
+		u8 tssr_index = TSSR_INDEX(offset);
+		u32 reg;
+
+		raw_spin_lock(&priv->lock);
+		reg = readl_relaxed(priv->base + TSSR(tssr_index));
+		reg |= (TIEN | chip_data) << TSSEL_SHIFT(tssr_offset);
+		writel_relaxed(reg, priv->base + TSSR(tssr_index));
+		raw_spin_unlock(&priv->lock);
+	}
+	irq_chip_enable_parent(d);
+}
+
+static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
+	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	u16 sense, tmp;
+
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_LEVEL_LOW:
+		sense = IITSR_IITSEL_LEVEL_LOW;
+		break;
+
+	case IRQ_TYPE_EDGE_FALLING:
+		sense = IITSR_IITSEL_EDGE_FALLING;
+		break;
+
+	case IRQ_TYPE_EDGE_RISING:
+		sense = IITSR_IITSEL_EDGE_RISING;
+		break;
+
+	case IRQ_TYPE_EDGE_BOTH:
+		sense = IITSR_IITSEL_EDGE_BOTH;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	raw_spin_lock(&priv->lock);
+	tmp = readl_relaxed(priv->base + IITSR);
+	tmp &= ~IITSR_IITSEL_MASK(hw_irq);
+	tmp |= IITSR_IITSEL(hw_irq, sense);
+	writel_relaxed(tmp, priv->base + IITSR);
+	raw_spin_unlock(&priv->lock);
+
+	return 0;
+}
+
+static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
+{
+	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	unsigned int hwirq = irqd_to_hwirq(d);
+	u32 titseln = hwirq - IRQC_TINT_START;
+	u32 offset;
+	u8 sense;
+	u32 reg;
+
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_RISING:
+		sense = TITSR_TITSEL_EDGE_RISING;
+		break;
+
+	case IRQ_TYPE_EDGE_FALLING:
+		sense = TITSR_TITSEL_EDGE_FALLING;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	offset = TITSR0;
+	if (titseln >= TITSR0_MAX_INT) {
+		titseln -= TITSR0_MAX_INT;
+		offset = TITSR1;
+	}
+
+	raw_spin_lock(&priv->lock);
+	reg = readl_relaxed(priv->base + offset);
+	reg &= ~(IRQ_MASK << (titseln * TITSEL_WIDTH));
+	reg |= sense << (titseln * TITSEL_WIDTH);
+	writel_relaxed(reg, priv->base + offset);
+	raw_spin_unlock(&priv->lock);
+
+	return 0;
+}
+
+static int rzg2l_irqc_set_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int hw_irq = irqd_to_hwirq(d);
+	int ret = -EINVAL;
+
+	if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
+		ret = rzg2l_irq_set_type(d, type);
+	else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
+		ret = rzg2l_tint_set_edge(d, type);
+	if (ret)
+		return ret;
+
+	return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
+}
+
+static const struct irq_chip irqc_chip = {
+	.name			= "rzg2l-irqc",
+	.irq_eoi		= rzg2l_irqc_eoi,
+	.irq_mask		= irq_chip_mask_parent,
+	.irq_unmask		= irq_chip_unmask_parent,
+	.irq_disable		= rzg2l_irqc_irq_disable,
+	.irq_enable		= rzg2l_irqc_irq_enable,
+	.irq_get_irqchip_state	= irq_chip_get_parent_state,
+	.irq_set_irqchip_state	= irq_chip_set_parent_state,
+	.irq_retrigger		= irq_chip_retrigger_hierarchy,
+	.irq_set_type		= rzg2l_irqc_set_type,
+	.flags			= IRQCHIP_MASK_ON_SUSPEND |
+				  IRQCHIP_SET_TYPE_MASKED |
+				  IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
+			    unsigned int nr_irqs, void *arg)
+{
+	struct rzg2l_irqc_priv *priv = domain->host_data;
+	unsigned long *chip_data = NULL;
+	struct irq_fwspec spec;
+	irq_hw_number_t hwirq;
+	int tint = -EINVAL;
+	unsigned int type;
+	unsigned int i;
+	int ret;
+
+	ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
+	if (ret)
+		return ret;
+
+	/*
+	 * For TINT interrupts ie where pinctrl driver is child of irqc domain
+	 * the hwirq and TINT are encoded in fwspec->param[0].
+	 * hwirq for TINT range from 9-40, hwirq is embedded 0-15 bits and TINT
+	 * from 16-31 bits. TINT from the pinctrl driver needs to be programmed
+	 * in IRQC registers to enable a given gpio pin as interrupt.
+	 */
+	if (hwirq > IRQC_IRQ_COUNT) {
+		tint = TINT_EXTRACT_GPIOINT(hwirq);
+		hwirq = TINT_EXTRACT_HWIRQ(hwirq);
+
+		if (hwirq < IRQC_TINT_START)
+			return -EINVAL;
+	}
+
+	if (hwirq > (IRQC_NUM_IRQ - 1))
+		return -EINVAL;
+
+	chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
+	if (!chip_data)
+		return -ENOMEM;
+	*chip_data = tint;
+
+	ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
+					    chip_data);
+	if (ret) {
+		kfree(chip_data);
+		return ret;
+	}
+
+	spec.fwnode = domain->parent->fwnode;
+	spec.param_count = priv->map[hwirq].args_count;
+	for (i = 0; i < spec.param_count; i++)
+		spec.param[i] = priv->map[hwirq].args[i];
+
+	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);
+	if (ret)
+		kfree(chip_data);
+
+	return ret;
+}
+
+static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
+				   unsigned int nr_irqs)
+{
+	struct irq_data *d;
+
+	d = irq_domain_get_irq_data(domain, virq);
+	if (d)
+		kfree(d->chip_data);
+
+	irq_domain_free_irqs_common(domain, virq, nr_irqs);
+}
+
+static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
+	.alloc = rzg2l_irqc_alloc,
+	.free = rzg2l_irqc_domain_free,
+	.translate = irq_domain_translate_twocell,
+};
+
+static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
+				struct device_node *np)
+{
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < IRQC_NUM_IRQ; i++) {
+		ret = of_irq_parse_one(np, i, &priv->map[i]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
+{
+	struct irq_domain *irq_domain, *parent_domain;
+	struct platform_device *pdev;
+	struct reset_control *resetn;
+	struct rzg2l_irqc_priv *priv;
+	int ret;
+
+	pdev = of_find_device_by_node(node);
+	if (!pdev)
+		return -ENODEV;
+
+	parent_domain = irq_find_host(parent);
+	if (!parent_domain) {
+		dev_err(&pdev->dev, "cannot find parent domain\n");
+		return -ENODEV;
+	}
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	ret = rzg2l_irqc_parse_map(priv, node);
+	if (ret) {
+		dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
+		return ret;
+	}
+
+	resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);
+	if (IS_ERR(resetn))
+		return IS_ERR(resetn);
+
+	ret = reset_control_deassert(resetn);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to deassert resetn pin, %d\n", ret);
+		return ret;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	ret = pm_runtime_resume_and_get(&pdev->dev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "pm_runtime_resume_and_get failed: %d\n", ret);
+		goto pm_disable;
+	}
+
+	raw_spin_lock_init(&priv->lock);
+
+	irq_domain = irq_domain_add_hierarchy(parent_domain, 0, IRQC_NUM_IRQ,
+					      node, &rzg2l_irqc_domain_ops,
+					      priv);
+	if (!irq_domain) {
+		dev_err(&pdev->dev, "failed to add irq domain\n");
+		ret = -ENOMEM;
+		goto pm_put;
+	}
+
+	return 0;
+
+pm_put:
+	pm_runtime_put(&pdev->dev);
+pm_disable:
+	pm_runtime_disable(&pdev->dev);
+	reset_control_assert(resetn);
+	return ret;
+}
+
+IRQCHIP_PLATFORM_DRIVER_BEGIN(rzg2l_irqc)
+IRQCHIP_MATCH("renesas,rzg2l-irqc", rzg2l_irqc_init)
+IRQCHIP_PLATFORM_DRIVER_END(rzg2l_irqc)
+MODULE_AUTHOR("Lad Prabhakar <[e-mail]>");
+MODULE_DESCRIPTION("Renesas RZ/G2L IRQC Driver");
+MODULE_LICENSE("GPL");