Commit 6dd64ee1 authored by Ludovic Barre's avatar Ludovic Barre Committed by Marc Zyngier
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irqchip/stm32: Add multi-bank management



-Prepare to manage multi-bank of external interrupts
(N banks of 32 inputs).
-Prepare to manage registers offsets by compatible
(registers offsets could be different follow per stm32 platform).

Signed-off-by: default avatarLudovic Barre <ludovic.barre@st.com>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
parent 0e7d7807
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+103 −46
Original line number Diff line number Diff line
@@ -14,27 +14,66 @@
#include <linux/of_address.h>
#include <linux/of_irq.h>

#define EXTI_IMR	0x0
#define EXTI_EMR	0x4
#define EXTI_RTSR	0x8
#define EXTI_FTSR	0xc
#define EXTI_SWIER	0x10
#define EXTI_PR		0x14
#define IRQS_PER_BANK 32

struct stm32_exti_bank {
	u32 imr_ofst;
	u32 emr_ofst;
	u32 rtsr_ofst;
	u32 ftsr_ofst;
	u32 swier_ofst;
	u32 pr_ofst;
};

static const struct stm32_exti_bank stm32f4xx_exti_b1 = {
	.imr_ofst	= 0x00,
	.emr_ofst	= 0x04,
	.rtsr_ofst	= 0x08,
	.ftsr_ofst	= 0x0C,
	.swier_ofst	= 0x10,
	.pr_ofst	= 0x14,
};

static const struct stm32_exti_bank *stm32f4xx_exti_banks[] = {
	&stm32f4xx_exti_b1,
};

static unsigned long stm32_exti_pending(struct irq_chip_generic *gc)
{
	const struct stm32_exti_bank *stm32_bank = gc->private;

	return irq_reg_readl(gc, stm32_bank->pr_ofst);
}

static void stm32_exti_irq_ack(struct irq_chip_generic *gc, u32 mask)
{
	const struct stm32_exti_bank *stm32_bank = gc->private;

	irq_reg_writel(gc, mask, stm32_bank->pr_ofst);
}

static void stm32_irq_handler(struct irq_desc *desc)
{
	struct irq_domain *domain = irq_desc_get_handler_data(desc);
	struct irq_chip_generic *gc = domain->gc->gc[0];
	struct irq_chip *chip = irq_desc_get_chip(desc);
	unsigned int virq, nbanks = domain->gc->num_chips;
	struct irq_chip_generic *gc;
	const struct stm32_exti_bank *stm32_bank;
	unsigned long pending;
	int n;
	int n, i, irq_base = 0;

	chained_irq_enter(chip, desc);

	while ((pending = irq_reg_readl(gc, EXTI_PR))) {
		for_each_set_bit(n, &pending, BITS_PER_LONG) {
			generic_handle_irq(irq_find_mapping(domain, n));
			irq_reg_writel(gc, BIT(n), EXTI_PR);
	for (i = 0; i < nbanks; i++, irq_base += IRQS_PER_BANK) {
		gc = irq_get_domain_generic_chip(domain, irq_base);
		stm32_bank = gc->private;

		while ((pending = stm32_exti_pending(gc))) {
			for_each_set_bit(n, &pending, IRQS_PER_BANK) {
				virq = irq_find_mapping(domain, irq_base + n);
				generic_handle_irq(virq);
				stm32_exti_irq_ack(gc, BIT(n));
			}
		}
	}

@@ -44,13 +83,14 @@ static void stm32_irq_handler(struct irq_desc *desc)
static int stm32_irq_set_type(struct irq_data *data, unsigned int type)
{
	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
	int pin = data->hwirq;
	const struct stm32_exti_bank *stm32_bank = gc->private;
	int pin = data->hwirq % IRQS_PER_BANK;
	u32 rtsr, ftsr;

	irq_gc_lock(gc);

	rtsr = irq_reg_readl(gc, EXTI_RTSR);
	ftsr = irq_reg_readl(gc, EXTI_FTSR);
	rtsr = irq_reg_readl(gc, stm32_bank->rtsr_ofst);
	ftsr = irq_reg_readl(gc, stm32_bank->ftsr_ofst);

	switch (type) {
	case IRQ_TYPE_EDGE_RISING:
@@ -70,8 +110,8 @@ static int stm32_irq_set_type(struct irq_data *data, unsigned int type)
		return -EINVAL;
	}

	irq_reg_writel(gc, rtsr, EXTI_RTSR);
	irq_reg_writel(gc, ftsr, EXTI_FTSR);
	irq_reg_writel(gc, rtsr, stm32_bank->rtsr_ofst);
	irq_reg_writel(gc, ftsr, stm32_bank->ftsr_ofst);

	irq_gc_unlock(gc);

@@ -81,17 +121,18 @@ static int stm32_irq_set_type(struct irq_data *data, unsigned int type)
static int stm32_irq_set_wake(struct irq_data *data, unsigned int on)
{
	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
	int pin = data->hwirq;
	const struct stm32_exti_bank *stm32_bank = gc->private;
	int pin = data->hwirq % IRQS_PER_BANK;
	u32 emr;

	irq_gc_lock(gc);

	emr = irq_reg_readl(gc, EXTI_EMR);
	emr = irq_reg_readl(gc, stm32_bank->emr_ofst);
	if (on)
		emr |= BIT(pin);
	else
		emr &= ~BIT(pin);
	irq_reg_writel(gc, emr, EXTI_EMR);
	irq_reg_writel(gc, emr, stm32_bank->emr_ofst);

	irq_gc_unlock(gc);

@@ -101,11 +142,12 @@ static int stm32_irq_set_wake(struct irq_data *data, unsigned int on)
static int stm32_exti_alloc(struct irq_domain *d, unsigned int virq,
			    unsigned int nr_irqs, void *data)
{
	struct irq_chip_generic *gc = d->gc->gc[0];
	struct irq_chip_generic *gc;
	struct irq_fwspec *fwspec = data;
	irq_hw_number_t hwirq;

	hwirq = fwspec->param[0];
	gc = irq_get_domain_generic_chip(d, hwirq);

	irq_map_generic_chip(d, virq, hwirq);
	irq_domain_set_info(d, virq, hwirq, &gc->chip_types->chip, gc,
@@ -129,8 +171,9 @@ struct irq_domain_ops irq_exti_domain_ops = {
	.free	= stm32_exti_free,
};

static int __init stm32_exti_init(struct device_node *node,
				  struct device_node *parent)
static int
__init stm32_exti_init(const struct stm32_exti_bank **stm32_exti_banks,
		       int bank_nr, struct device_node *node)
{
	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
	int nr_irqs, nr_exti, ret, i;
@@ -144,14 +187,7 @@ static int __init stm32_exti_init(struct device_node *node,
		return -ENOMEM;
	}

	/* Determine number of irqs supported */
	writel_relaxed(~0UL, base + EXTI_RTSR);
	nr_exti = fls(readl_relaxed(base + EXTI_RTSR));
	writel_relaxed(0, base + EXTI_RTSR);

	pr_info("%pOF: %d External IRQs detected\n", node, nr_exti);

	domain = irq_domain_add_linear(node, nr_exti,
	domain = irq_domain_add_linear(node, bank_nr * IRQS_PER_BANK,
				       &irq_exti_domain_ops, NULL);
	if (!domain) {
		pr_err("%s: Could not register interrupt domain.\n",
@@ -160,7 +196,7 @@ static int __init stm32_exti_init(struct device_node *node,
		goto out_unmap;
	}

	ret = irq_alloc_domain_generic_chips(domain, nr_exti, 1, "exti",
	ret = irq_alloc_domain_generic_chips(domain, IRQS_PER_BANK, 1, "exti",
					     handle_edge_irq, clr, 0, 0);
	if (ret) {
		pr_err("%pOF: Could not allocate generic interrupt chip.\n",
@@ -168,18 +204,32 @@ static int __init stm32_exti_init(struct device_node *node,
		goto out_free_domain;
	}

	gc = domain->gc->gc[0];
	for (i = 0; i < bank_nr; i++) {
		const struct stm32_exti_bank *stm32_bank = stm32_exti_banks[i];
		u32 irqs_mask;

		gc = irq_get_domain_generic_chip(domain, i * IRQS_PER_BANK);

		gc->reg_base = base;
		gc->chip_types->type = IRQ_TYPE_EDGE_BOTH;
	gc->chip_types->chip.name          = gc->chip_types[0].chip.name;
		gc->chip_types->chip.irq_ack = irq_gc_ack_set_bit;
		gc->chip_types->chip.irq_mask = irq_gc_mask_clr_bit;
		gc->chip_types->chip.irq_unmask = irq_gc_mask_set_bit;
		gc->chip_types->chip.irq_set_type = stm32_irq_set_type;
		gc->chip_types->chip.irq_set_wake = stm32_irq_set_wake;
	gc->chip_types->regs.ack           = EXTI_PR;
	gc->chip_types->regs.mask          = EXTI_IMR;
	gc->chip_types->handler            = handle_edge_irq;
		gc->chip_types->regs.ack = stm32_bank->pr_ofst;
		gc->chip_types->regs.mask = stm32_bank->imr_ofst;
		gc->private = (void *)stm32_bank;

		/* Determine number of irqs supported */
		writel_relaxed(~0UL, base + stm32_bank->rtsr_ofst);
		irqs_mask = readl_relaxed(base + stm32_bank->rtsr_ofst);
		nr_exti = fls(readl_relaxed(base + stm32_bank->rtsr_ofst));
		writel_relaxed(0, base + stm32_bank->rtsr_ofst);

		pr_info("%s: bank%d, External IRQs available:%#x\n",
			node->full_name, i, irqs_mask);
	}

	nr_irqs = of_irq_count(node);
	for (i = 0; i < nr_irqs; i++) {
@@ -198,4 +248,11 @@ out_unmap:
	return ret;
}

IRQCHIP_DECLARE(stm32_exti, "st,stm32-exti", stm32_exti_init);
static int __init stm32f4_exti_of_init(struct device_node *np,
				       struct device_node *parent)
{
	return stm32_exti_init(stm32f4xx_exti_banks,
			ARRAY_SIZE(stm32f4xx_exti_banks), np);
}

IRQCHIP_DECLARE(stm32f4_exti, "st,stm32-exti", stm32f4_exti_of_init);