diff options
Diffstat (limited to 'drivers/irqchip/irq-davinci-aintc.c')
| -rw-r--r-- | drivers/irqchip/irq-davinci-aintc.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-davinci-aintc.c b/drivers/irqchip/irq-davinci-aintc.c new file mode 100644 index 000000000..810ccc4fe --- /dev/null +++ b/drivers/irqchip/irq-davinci-aintc.c @@ -0,0 +1,163 @@ +// 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); +} |