linux/drivers/irqchip/irq-davinci-aintc.c

164 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
//
// Copyright (C) 2006, 2019 Texas Instruments.
//
// Interrupt handler for DaVinci boards.
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip/irq-davinci-aintc.h>
#include <linux/io.h>
#include <linux/irqdomain.h>
#include <asm/exception.h>
#define DAVINCI_AINTC_FIQ_REG0 0x00
#define DAVINCI_AINTC_FIQ_REG1 0x04
#define DAVINCI_AINTC_IRQ_REG0 0x08
#define DAVINCI_AINTC_IRQ_REG1 0x0c
#define DAVINCI_AINTC_IRQ_IRQENTRY 0x14
#define DAVINCI_AINTC_IRQ_ENT_REG0 0x18
#define DAVINCI_AINTC_IRQ_ENT_REG1 0x1c
#define DAVINCI_AINTC_IRQ_INCTL_REG 0x20
#define DAVINCI_AINTC_IRQ_EABASE_REG 0x24
#define DAVINCI_AINTC_IRQ_INTPRI0_REG 0x30
#define DAVINCI_AINTC_IRQ_INTPRI7_REG 0x4c
static void __iomem *davinci_aintc_base;
static struct irq_domain *davinci_aintc_irq_domain;
static inline void davinci_aintc_writel(unsigned long value, int offset)
{
writel_relaxed(value, davinci_aintc_base + offset);
}
static inline unsigned long davinci_aintc_readl(int offset)
{
return readl_relaxed(davinci_aintc_base + offset);
}
static __init void
davinci_aintc_setup_gc(void __iomem *base,
unsigned int irq_start, unsigned int num)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_get_domain_generic_chip(davinci_aintc_irq_domain, irq_start);
gc->reg_base = base;
gc->irq_base = irq_start;
ct = gc->chip_types;
ct->chip.irq_ack = irq_gc_ack_set_bit;
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->regs.ack = DAVINCI_AINTC_IRQ_REG0;
ct->regs.mask = DAVINCI_AINTC_IRQ_ENT_REG0;
irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
IRQ_NOREQUEST | IRQ_NOPROBE, 0);
}
static asmlinkage void __exception_irq_entry
davinci_aintc_handle_irq(struct pt_regs *regs)
{
int irqnr = davinci_aintc_readl(DAVINCI_AINTC_IRQ_IRQENTRY);
/*
* Use the formula for entry vector index generation from section
* 8.3.3 of the manual.
*/
irqnr >>= 2;
irqnr -= 1;
handle_domain_irq(davinci_aintc_irq_domain, irqnr, regs);
}
/* ARM Interrupt Controller Initialization */
void __init davinci_aintc_init(const struct davinci_aintc_config *config)
{
unsigned int irq_off, reg_off, prio, shift;
void __iomem *req;
int ret, irq_base;
const u8 *prios;
req = request_mem_region(config->reg.start,
resource_size(&config->reg),
"davinci-cp-intc");
if (!req) {
pr_err("%s: register range busy\n", __func__);
return;
}
davinci_aintc_base = ioremap(config->reg.start,
resource_size(&config->reg));
if (!davinci_aintc_base) {
pr_err("%s: unable to ioremap register range\n", __func__);
return;
}
/* Clear all interrupt requests */
davinci_aintc_writel(~0x0, DAVINCI_AINTC_FIQ_REG0);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_FIQ_REG1);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_IRQ_REG0);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_IRQ_REG1);
/* Disable all interrupts */
davinci_aintc_writel(0x0, DAVINCI_AINTC_IRQ_ENT_REG0);
davinci_aintc_writel(0x0, DAVINCI_AINTC_IRQ_ENT_REG1);
/* Interrupts disabled immediately, IRQ entry reflects all */
davinci_aintc_writel(0x0, DAVINCI_AINTC_IRQ_INCTL_REG);
/* we don't use the hardware vector table, just its entry addresses */
davinci_aintc_writel(0, DAVINCI_AINTC_IRQ_EABASE_REG);
/* Clear all interrupt requests */
davinci_aintc_writel(~0x0, DAVINCI_AINTC_FIQ_REG0);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_FIQ_REG1);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_IRQ_REG0);
davinci_aintc_writel(~0x0, DAVINCI_AINTC_IRQ_REG1);
prios = config->prios;
for (reg_off = DAVINCI_AINTC_IRQ_INTPRI0_REG;
reg_off <= DAVINCI_AINTC_IRQ_INTPRI7_REG; reg_off += 4) {
for (shift = 0, prio = 0; shift < 32; shift += 4, prios++)
prio |= (*prios & 0x07) << shift;
davinci_aintc_writel(prio, reg_off);
}
irq_base = irq_alloc_descs(-1, 0, config->num_irqs, 0);
if (irq_base < 0) {
pr_err("%s: unable to allocate interrupt descriptors: %d\n",
__func__, irq_base);
return;
}
davinci_aintc_irq_domain = irq_domain_add_legacy(NULL,
config->num_irqs, irq_base, 0,
&irq_domain_simple_ops, NULL);
if (!davinci_aintc_irq_domain) {
pr_err("%s: unable to create interrupt domain\n", __func__);
return;
}
ret = irq_alloc_domain_generic_chips(davinci_aintc_irq_domain, 32, 1,
"AINTC", handle_edge_irq,
IRQ_NOREQUEST | IRQ_NOPROBE, 0, 0);
if (ret) {
pr_err("%s: unable to allocate generic irq chips for domain\n",
__func__);
return;
}
for (irq_off = 0, reg_off = 0;
irq_off < config->num_irqs;
irq_off += 32, reg_off += 0x04)
davinci_aintc_setup_gc(davinci_aintc_base + reg_off,
irq_base + irq_off, 32);
set_handle_irq(davinci_aintc_handle_irq);
}