Commit ea4aeaa5 authored by Mark-PK Tsai's avatar Mark-PK Tsai Committed by Marc Zyngier
Browse files

irqchip/irq-mst: Support polarity configuration 



Support irq polarity configuration and save and restore the config
when system suspend and resume.

Signed-off-by: default avatarMark-PK Tsai <mark-pk.tsai@mediatek.com>
[maz: fixed irq_set_type callback]
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210315131848.31840-1-mark-pk.tsai@mediatek.com
parent fead4dd4

drivers/irqchip/irq-mst-intc.c

+95 −3
Original line number Diff line number Diff line
@@ -13,15 +13,27 @@ 
#include <linux/of_irq.h>

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <linux/syscore_ops.h>



#define MST_INTC_MAX_IRQS	64



#define INTC_MASK		0x0

#define INTC_REV_POLARITY	0x10

#define INTC_EOI		0x20



#ifdef CONFIG_PM_SLEEP

static LIST_HEAD(mst_intc_list);

#endif



struct mst_intc_chip_data {

	raw_spinlock_t	lock;

	unsigned int	irq_start, nr_irqs;

	void __iomem	*base;

	bool		no_eoi;

#ifdef CONFIG_PM_SLEEP

	struct list_head entry;

	u16 saved_polarity_conf[DIV_ROUND_UP(MST_INTC_MAX_IRQS, 16)];

#endif

};



static void mst_set_irq(struct irq_data *d, u32 offset)
@@ -78,6 +90,24 @@ static void mst_intc_eoi_irq(struct irq_data *d) 
	irq_chip_eoi_parent(d);

}



static int mst_irq_chip_set_type(struct irq_data *data, unsigned int type)

{

	switch (type) {

	case IRQ_TYPE_LEVEL_LOW:

	case IRQ_TYPE_EDGE_FALLING:

		mst_set_irq(data, INTC_REV_POLARITY);

		break;

	case IRQ_TYPE_LEVEL_HIGH:

	case IRQ_TYPE_EDGE_RISING:

		mst_clear_irq(data, INTC_REV_POLARITY);

		break;

	default:

		return -EINVAL;

	}



	return irq_chip_set_type_parent(data, IRQ_TYPE_LEVEL_HIGH);

}



static struct irq_chip mst_intc_chip = {

	.name			= "mst-intc",

	.irq_mask		= mst_intc_mask_irq,
@@ -87,13 +117,62 @@ static struct irq_chip mst_intc_chip = { 
	.irq_set_irqchip_state	= irq_chip_set_parent_state,

	.irq_set_affinity	= irq_chip_set_affinity_parent,

	.irq_set_vcpu_affinity	= irq_chip_set_vcpu_affinity_parent,

	.irq_set_type		= irq_chip_set_type_parent,

	.irq_set_type		= mst_irq_chip_set_type,

	.irq_retrigger		= irq_chip_retrigger_hierarchy,

	.flags			= IRQCHIP_SET_TYPE_MASKED |

				  IRQCHIP_SKIP_SET_WAKE |

				  IRQCHIP_MASK_ON_SUSPEND,

};



#ifdef CONFIG_PM_SLEEP

static void mst_intc_polarity_save(struct mst_intc_chip_data *cd)

{

	int i;

	void __iomem *addr = cd->base + INTC_REV_POLARITY;



	for (i = 0; i < DIV_ROUND_UP(cd->nr_irqs, 16); i++)

		cd->saved_polarity_conf[i] = readw_relaxed(addr + i * 4);

}



static void mst_intc_polarity_restore(struct mst_intc_chip_data *cd)

{

	int i;

	void __iomem *addr = cd->base + INTC_REV_POLARITY;



	for (i = 0; i < DIV_ROUND_UP(cd->nr_irqs, 16); i++)

		writew_relaxed(cd->saved_polarity_conf[i], addr + i * 4);

}



static void mst_irq_resume(void)

{

	struct mst_intc_chip_data *cd;



	list_for_each_entry(cd, &mst_intc_list, entry)

		mst_intc_polarity_restore(cd);

}



static int mst_irq_suspend(void)

{

	struct mst_intc_chip_data *cd;



	list_for_each_entry(cd, &mst_intc_list, entry)

		mst_intc_polarity_save(cd);

	return 0;

}



static struct syscore_ops mst_irq_syscore_ops = {

	.suspend	= mst_irq_suspend,

	.resume		= mst_irq_resume,

};



static int __init mst_irq_pm_init(void)

{

	register_syscore_ops(&mst_irq_syscore_ops);

	return 0;

}

late_initcall(mst_irq_pm_init);

#endif



static int mst_intc_domain_translate(struct irq_domain *d,

				     struct irq_fwspec *fwspec,

				     unsigned long *hwirq,
@@ -145,6 +224,15 @@ static int mst_intc_domain_alloc(struct irq_domain *domain, unsigned int virq, 
	parent_fwspec = *fwspec;

	parent_fwspec.fwnode = domain->parent->fwnode;

	parent_fwspec.param[1] = cd->irq_start + hwirq;



	/*

	 * mst-intc latch the interrupt request if it's edge triggered,

	 * so the output signal to parent GIC is always level sensitive.

	 * And if the irq signal is active low, configure it to active high

	 * to meet GIC SPI spec in mst_irq_chip_set_type via REV_POLARITY bit.

	 */

	parent_fwspec.param[2] = IRQ_TYPE_LEVEL_HIGH;



	return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_fwspec);

}
@@ -193,6 +281,10 @@ static int __init mst_intc_of_init(struct device_node *dn, 
		return -ENOMEM;

	}



#ifdef CONFIG_PM_SLEEP

	INIT_LIST_HEAD(&cd->entry);

	list_add_tail(&cd->entry, &mst_intc_list);

#endif

	return 0;

}