// SPDX-License-Identifier: GPL-2.0+ /* * Copyright 2010 Broadcom * Copyright 2012 Simon Arlott, Chris Boot, Stephen Warren * * Quirk 1: Shortcut interrupts don't set the bank 1/2 register pending bits * * If an interrupt fires on bank 1 that isn't in the shortcuts list, bit 8 * on bank 0 is set to signify that an interrupt in bank 1 has fired, and * to look in the bank 1 status register for more information. * * If an interrupt fires on bank 1 that _is_ in the shortcuts list, its * shortcut bit in bank 0 is set as well as its interrupt bit in the bank 1 * status register, but bank 0 bit 8 is _not_ set. * * Quirk 2: You can't mask the register 1/2 pending interrupts * * In a proper cascaded interrupt controller, the interrupt lines with * cascaded interrupt controllers on them are just normal interrupt lines. * You can mask the interrupts and get on with things. With this controller * you can't do that. * * Quirk 3: The shortcut interrupts can't be (un)masked in bank 0 * * Those interrupts that have shortcuts can only be masked/unmasked in * their respective banks' enable/disable registers. Doing so in the bank 0 * enable/disable registers has no effect. * * The FIQ control register: * Bits 0-6: IRQ (index in order of interrupts from banks 1, 2, then 0) * Bit 7: Enable FIQ generation * Bits 8+: Unused * * An interrupt must be disabled before configuring it for FIQ generation * otherwise both handlers will fire at the same time! */ #include #include #include #include #include #include #include /* Put the bank and irq (32 bits) into the hwirq */ #define MAKE_HWIRQ(b, n) ((b << 5) | (n)) #define HWIRQ_BANK(i) (i >> 5) #define HWIRQ_BIT(i) BIT(i & 0x1f) #define NR_IRQS_BANK0 8 #define BANK0_HWIRQ_MASK 0xff /* Shortcuts can't be disabled so any unknown new ones need to be masked */ #define SHORTCUT1_MASK 0x00007c00 #define SHORTCUT2_MASK 0x001f8000 #define SHORTCUT_SHIFT 10 #define BANK1_HWIRQ BIT(8) #define BANK2_HWIRQ BIT(9) #define BANK0_VALID_MASK (BANK0_HWIRQ_MASK | BANK1_HWIRQ | BANK2_HWIRQ \ | SHORTCUT1_MASK | SHORTCUT2_MASK) #define REG_FIQ_CONTROL 0x0c #define NR_BANKS 3 #define IRQS_PER_BANK 32 static const int reg_pending[] __initconst = { 0x00, 0x04, 0x08 }; static const int reg_enable[] __initconst = { 0x18, 0x10, 0x14 }; static const int reg_disable[] __initconst = { 0x24, 0x1c, 0x20 }; static const int bank_irqs[] __initconst = { 8, 32, 32 }; static const int shortcuts[] = { 7, 9, 10, 18, 19, /* Bank 1 */ 21, 22, 23, 24, 25, 30 /* Bank 2 */ }; struct armctrl_ic { void __iomem *base; void __iomem *pending[NR_BANKS]; void __iomem *enable[NR_BANKS]; void __iomem *disable[NR_BANKS]; struct irq_domain *domain; }; static struct armctrl_ic intc __read_mostly; static void __exception_irq_entry bcm2835_handle_irq( struct pt_regs *regs); static void bcm2836_chained_handle_irq(struct irq_desc *desc); static void armctrl_mask_irq(struct irq_data *d) { writel_relaxed(HWIRQ_BIT(d->hwirq), intc.disable[HWIRQ_BANK(d->hwirq)]); } static void armctrl_unmask_irq(struct irq_data *d) { writel_relaxed(HWIRQ_BIT(d->hwirq), intc.enable[HWIRQ_BANK(d->hwirq)]); } static struct irq_chip armctrl_chip = { .name = "ARMCTRL-level", .irq_mask = armctrl_mask_irq, .irq_unmask = armctrl_unmask_irq }; static int armctrl_xlate(struct irq_domain *d, struct device_node *ctrlr, const u32 *intspec, unsigned int intsize, unsigned long *out_hwirq, unsigned int *out_type) { if (WARN_ON(intsize != 2)) return -EINVAL; if (WARN_ON(intspec[0] >= NR_BANKS)) return -EINVAL; if (WARN_ON(intspec[1] >= IRQS_PER_BANK)) return -EINVAL; if (WARN_ON(intspec[0] == 0 && intspec[1] >= NR_IRQS_BANK0)) return -EINVAL; *out_hwirq = MAKE_HWIRQ(intspec[0], intspec[1]); *out_type = IRQ_TYPE_NONE; return 0; } static const struct irq_domain_ops armctrl_ops = { .xlate = armctrl_xlate }; static int __init armctrl_of_init(struct device_node *node, struct device_node *parent, bool is_2836) { void __iomem *base; int irq, b, i; base = of_iomap(node, 0); if (!base) panic("%pOF: unable to map IC registers\n", node); intc.domain = irq_domain_add_linear(node, MAKE_HWIRQ(NR_BANKS, 0), &armctrl_ops, NULL); if (!intc.domain) panic("%pOF: unable to create IRQ domain\n", node); for (b = 0; b < NR_BANKS; b++) { intc.pending[b] = base + reg_pending[b]; intc.enable[b] = base + reg_enable[b]; intc.disable[b] = base + reg_disable[b]; for (i = 0; i < bank_irqs[b]; i++) { irq = irq_create_mapping(intc.domain, MAKE_HWIRQ(b, i)); BUG_ON(irq <= 0); irq_set_chip_and_handler(irq, &armctrl_chip, handle_level_irq); irq_set_probe(irq); } } if (is_2836) { int parent_irq = irq_of_parse_and_map(node, 0); if (!parent_irq) { panic("%pOF: unable to get parent interrupt.\n", node); } irq_set_chained_handler(parent_irq, bcm2836_chained_handle_irq); } else { set_handle_irq(bcm2835_handle_irq); } return 0; } static int __init bcm2835_armctrl_of_init(struct device_node *node, struct device_node *parent) { return armctrl_of_init(node, parent, false); } static int __init bcm2836_armctrl_of_init(struct device_node *node, struct device_node *parent) { return armctrl_of_init(node, parent, true); } /* * Handle each interrupt across the entire interrupt controller. This reads the * status register before handling each interrupt, which is necessary given that * handle_IRQ may briefly re-enable interrupts for soft IRQ handling. */ static u32 armctrl_translate_bank(int bank) { u32 stat = readl_relaxed(intc.pending[bank]); return MAKE_HWIRQ(bank, ffs(stat) - 1); } static u32 armctrl_translate_shortcut(int bank, u32 stat) { return MAKE_HWIRQ(bank, shortcuts[ffs(stat >> SHORTCUT_SHIFT) - 1]); } static u32 get_next_armctrl_hwirq(void) { u32 stat = readl_relaxed(intc.pending[0]) & BANK0_VALID_MASK; if (stat == 0) return ~0; else if (stat & BANK0_HWIRQ_MASK) return MAKE_HWIRQ(0, ffs(stat & BANK0_HWIRQ_MASK) - 1); else if (stat & SHORTCUT1_MASK) return armctrl_translate_shortcut(1, stat & SHORTCUT1_MASK); else if (stat & SHORTCUT2_MASK) return armctrl_translate_shortcut(2, stat & SHORTCUT2_MASK); else if (stat & BANK1_HWIRQ) return armctrl_translate_bank(1); else if (stat & BANK2_HWIRQ) return armctrl_translate_bank(2); else BUG(); } static void __exception_irq_entry bcm2835_handle_irq( struct pt_regs *regs) { u32 hwirq; while ((hwirq = get_next_armctrl_hwirq()) != ~0) handle_domain_irq(intc.domain, hwirq, regs); } static void bcm2836_chained_handle_irq(struct irq_desc *desc) { u32 hwirq; while ((hwirq = get_next_armctrl_hwirq()) != ~0) generic_handle_irq(irq_linear_revmap(intc.domain, hwirq)); } IRQCHIP_DECLARE(bcm2835_armctrl_ic, "brcm,bcm2835-armctrl-ic", bcm2835_armctrl_of_init); IRQCHIP_DECLARE(bcm2836_armctrl_ic, "brcm,bcm2836-armctrl-ic", bcm2836_armctrl_of_init);