Re: [PATCH v3 5/5] pinctrl: renesas: pinctrl-rzg2l: Add IRQ domain to handle GPIO interrupt

Marc Zyngier
2022-05-12T11:16:23Z

On Wed, 11 May 2022 19:32:10 +0100,
Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
>
> Add IRQ domian to RZ/G2L pinctrl driver to handle GPIO interrupt.
>
> GPIO0-GPIO122 pins can be used as IRQ lines but only 32 pins can be
> used as IRQ lines at given time. Selection of pins as IRQ lines
> is handled by IA55 (which is the IRQC block) which sits in between the
> GPIO and GIC.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
> drivers/pinctrl/renesas/pinctrl-rzg2l.c | 202 ++++++++++++++++++++++++
> 1 file changed, 202 insertions(+)
>
> diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> index a48cac55152c..af2c739cdbaa 100644
> --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> @@ -9,8 +9,10 @@
> #include <linux/clk.h>
> #include <linux/gpio/driver.h>
> #include <linux/io.h>
> +#include <linux/interrupt.h>
> #include <linux/module.h>
> #include <linux/of_device.h>
> +#include <linux/of_irq.h>
> #include <linux/pinctrl/pinconf-generic.h>
> #include <linux/pinctrl/pinconf.h>
> #include <linux/pinctrl/pinctrl.h>
> @@ -89,6 +91,7 @@
> #define PIN(n) (0x0800 + 0x10 + (n))
> #define IOLH(n) (0x1000 + (n) * 8)
> #define IEN(n) (0x1800 + (n) * 8)
> +#define ISEL(n) (0x2c80 + (n) * 8)
> #define PWPR (0x3014)
> #define SD_CH(n) (0x3000 + (n) * 4)
> #define QSPI (0x3008)
> @@ -112,6 +115,10 @@
> #define RZG2L_PIN_ID_TO_PORT_OFFSET(id) (RZG2L_PIN_ID_TO_PORT(id) + 0x10)
> #define RZG2L_PIN_ID_TO_PIN(id) ((id) % RZG2L_PINS_PER_PORT)
>
> +#define RZG2L_TINT_MAX_INTERRUPT 32
> +#define RZG2L_TINT_IRQ_START_INDEX 9
> +#define RZG2L_PACK_HWIRQ(t, i) (((t) << 16) | (i))
> +
> struct rzg2l_dedicated_configs {
> const char *name;
> u32 config;
> @@ -137,6 +144,9 @@ struct rzg2l_pinctrl {
>
> struct gpio_chip gpio_chip;
> struct pinctrl_gpio_range gpio_range;
> + DECLARE_BITMAP(tint_slot, RZG2L_TINT_MAX_INTERRUPT);
> + spinlock_t bitmap_lock;
> + unsigned int hwirq[RZG2L_TINT_MAX_INTERRUPT];
>
> spinlock_t lock;
> };
> @@ -883,6 +893,8 @@ static int rzg2l_gpio_get(struct gpio_chip *chip, unsigned int offset)
>
> static void rzg2l_gpio_free(struct gpio_chip *chip, unsigned int offset)
> {
> + unsigned int virq;
> +
> pinctrl_gpio_free(chip->base + offset);
>
> /*
> @@ -890,6 +902,10 @@ static void rzg2l_gpio_free(struct gpio_chip *chip, unsigned int offset)
> * drive the GPIO pin as an output.
> */
> rzg2l_gpio_direction_input(chip, offset);
> +
> + virq = irq_find_mapping(chip->irq.domain, offset);
> + if (virq)
> + irq_dispose_mapping(virq);
> }
>
> static const char * const rzg2l_gpio_names[] = {
> @@ -1104,14 +1120,190 @@ static struct {
> }
> };
>
> +static int rzg2l_gpio_get_gpioint(unsigned int virq)
> +{
> + unsigned int gpioint;
> + unsigned int i;
> + u32 port, bit;
> +
> + port = virq / 8;
> + bit = virq % 8;
> +
> + if (port >= ARRAY_SIZE(rzg2l_gpio_configs) ||
> + bit >= RZG2L_GPIO_PORT_GET_PINCNT(rzg2l_gpio_configs[port]))
> + return -EINVAL;
> +
> + gpioint = bit;
> + for (i = 0; i < port; i++)
> + gpioint += RZG2L_GPIO_PORT_GET_PINCNT(rzg2l_gpio_configs[i]);
> +
> + return gpioint;
> +}
> +
> +static void rzg2l_gpio_irq_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) {
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct rzg2l_pinctrl *pctrl = container_of(gc, struct rzg2l_pinctrl, gpio_chip);
> + irq_hw_number_t hwirq = irqd_to_hwirq(d);
> + unsigned long flags;
> + unsigned int i;
> +
> + for (i = 0; i < RZG2L_TINT_MAX_INTERRUPT; i++) {
> + if (pctrl->hwirq[i] == hwirq) {
> + spin_lock_irqsave(&pctrl->bitmap_lock, flags);
> + bitmap_release_region(pctrl->tint_slot, i, get_order(1));
> + spin_unlock_irqrestore(&pctrl->bitmap_lock, flags);
> + pctrl->hwirq[i] = 0;
> + break;
> + }
> + }
> + }
> + irq_domain_free_irqs_common(domain, virq, nr_irqs);
> +}
> +
> +static void rzg2l_gpio_irq_disable(struct irq_data *d)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct rzg2l_pinctrl *pctrl = container_of(gc, struct rzg2l_pinctrl, gpio_chip);
> + unsigned int hwirq = irqd_to_hwirq(d);
> + unsigned long flags;
> + void __iomem *addr;
> + u32 port;
> + u8 bit;
> +
> + port = RZG2L_PIN_ID_TO_PORT(hwirq);
> + bit = RZG2L_PIN_ID_TO_PIN(hwirq);
> +
> + addr = pctrl->base + ISEL(port);
> + if (bit >= 4) {
> + bit -= 4;
> + addr += 4;
> + }
> +
> + spin_lock_irqsave(&pctrl->lock, flags);
> + writel(readl(addr) & ~BIT(bit * 8), addr);
> + spin_unlock_irqrestore(&pctrl->lock, flags);
> +
> + irq_chip_disable_parent(d);
> +}
> +
> +static void rzg2l_gpio_irq_enable(struct irq_data *d)
> +{
> + struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> + struct rzg2l_pinctrl *pctrl = container_of(gc, struct rzg2l_pinctrl, gpio_chip);
> + unsigned int hwirq = irqd_to_hwirq(d);
> + unsigned long flags;
> + void __iomem *addr;
> + u32 port;
> + u8 bit;
> +
> + port = RZG2L_PIN_ID_TO_PORT(hwirq);
> + bit = RZG2L_PIN_ID_TO_PIN(hwirq);
> +
> + addr = pctrl->base + ISEL(port);
> + if (bit >= 4) {
> + bit -= 4;
> + addr += 4;
> + }
> +
> + spin_lock_irqsave(&pctrl->lock, flags);
> + writel(readl(addr) | BIT(bit * 8), addr);
> + spin_unlock_irqrestore(&pctrl->lock, flags);
> +
> + irq_chip_enable_parent(d);
> +}
> +
> +static int rzg2l_gpio_irq_set_type(struct irq_data *d, unsigned int type)
> +{
> + return irq_chip_set_type_parent(d, type);
> +}
> +
> +static void rzg2l_gpio_irqc_eoi(struct irq_data *d)
> +{
> + irq_chip_eoi_parent(d);
> +}
> +
> +static struct irq_chip rzg2l_gpio_irqchip = {
> + .name = "rzg2l-gpio",
> + .irq_disable = rzg2l_gpio_irq_disable,
> + .irq_enable = rzg2l_gpio_irq_enable,
> + .irq_mask = irq_chip_mask_parent,
> + .irq_unmask = irq_chip_unmask_parent,
> + .irq_set_type = rzg2l_gpio_irq_set_type,
> + .irq_eoi = rzg2l_gpio_irqc_eoi,

Please see the changes[1] that are queued in -next around immutable
GPIO irqchips. This needs to be made const, the enable/disable methods
have the right callbacks added, the resource management methods
plumbed, and the correct flag exposed.

> +};
> +
> +static int rzg2l_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
> + unsigned int child,
> + unsigned int child_type,
> + unsigned int *parent,
> + unsigned int *parent_type)
> +{
> + struct rzg2l_pinctrl *pctrl = gpiochip_get_data(gc);
> + unsigned long flags;
> + int gpioint, irq;
> +
> + gpioint = rzg2l_gpio_get_gpioint(child);
> + if (gpioint < 0)
> + return gpioint;
> +
> + spin_lock_irqsave(&pctrl->bitmap_lock, flags);
> + irq = bitmap_find_free_region(pctrl->tint_slot, RZG2L_TINT_MAX_INTERRUPT, get_order(1));
> + spin_unlock_irqrestore(&pctrl->bitmap_lock, flags);
> + if (irq < 0)
> + return -ENOSPC;
> + pctrl->hwirq[irq] = child;
> + irq += RZG2L_TINT_IRQ_START_INDEX;
> +
> + /* All these interrupts are level high in the CPU */
> + *parent_type = IRQ_TYPE_LEVEL_HIGH;
> + *parent = RZG2L_PACK_HWIRQ(gpioint, irq);
> + return 0;
> +}
> +
> +static void *rzg2l_gpio_populate_parent_fwspec(struct gpio_chip *chip,
> + unsigned int parent_hwirq,
> + unsigned int parent_type)
> +{
> + struct irq_fwspec *fwspec;
> +
> + fwspec = kzalloc(sizeof(*fwspec), GFP_KERNEL);
> + if (!fwspec)
> + return NULL;
> +
> + fwspec->fwnode = chip->irq.parent_domain->fwnode;
> + fwspec->param_count = 2;
> + fwspec->param[0] = parent_hwirq;
> + fwspec->param[1] = parent_type;
> +
> + return fwspec;
> +}
> +
> static int rzg2l_gpio_register(struct rzg2l_pinctrl *pctrl)
> {
> struct device_node *np = pctrl->dev->of_node;
> struct gpio_chip *chip = &pctrl->gpio_chip;
> const char *name = dev_name(pctrl->dev);
> + struct irq_domain *parent_domain;
> struct of_phandle_args of_args;
> + struct device_node *parent_np;
> + struct gpio_irq_chip *girq;
> int ret;
>
> + parent_np = of_irq_find_parent(np);
> + if (!parent_np)
> + return -ENXIO;
> +
> + parent_domain = irq_find_host(parent_np);
> + of_node_put(parent_np);
> + if (!parent_domain)
> + return -EPROBE_DEFER;
> +
> ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 0, &of_args);
> if (ret) {
> dev_err(pctrl->dev, "Unable to parse gpio-ranges\n");
> @@ -1138,6 +1330,15 @@ static int rzg2l_gpio_register(struct rzg2l_pinctrl *pctrl)
> chip->base = -1;
> chip->ngpio = of_args.args[2];
>
> + girq = &chip->irq;

Same thing, this needs to use the appropriate setter.

> + girq->chip = &rzg2l_gpio_irqchip;
> + girq->fwnode = of_node_to_fwnode(np);
> + girq->parent_domain = parent_domain;
> + girq->child_to_parent_hwirq = rzg2l_gpio_child_to_parent_hwirq;
> + girq->populate_parent_alloc_arg = rzg2l_gpio_populate_parent_fwspec;
> + girq->child_irq_domain_ops.free = rzg2l_gpio_irq_domain_free;
> + girq->ngirq = RZG2L_TINT_MAX_INTERRUPT;
> +
> pctrl->gpio_range.id = 0;
> pctrl->gpio_range.pin_base = 0;
> pctrl->gpio_range.base = 0;
> @@ -1253,6 +1454,7 @@ static int rzg2l_pinctrl_probe(struct platform_device *pdev)
> }
>
> spin_lock_init(&pctrl->lock);
> + spin_lock_init(&pctrl->bitmap_lock);
>
> platform_set_drvdata(pdev, pctrl);
>
> --
> 2.25.1
>
>

Thanks,

M.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=irq/gpio-immutable

--
Without deviation from the norm, progress is not possible.