| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Generic Broadcom Set Top Box Level 2 Interrupt controller driver |
| * |
| * Copyright (C) 2014-2024 Broadcom |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/spinlock.h> |
| #include <linux/of.h> |
| #include <linux/of_irq.h> |
| #include <linux/of_address.h> |
| #include <linux/of_platform.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/io.h> |
| #include <linux/irqdomain.h> |
| #include <linux/irqchip.h> |
| #include <linux/irqchip/chained_irq.h> |
| |
| struct brcmstb_intc_init_params { |
| irq_flow_handler_t handler; |
| int cpu_status; |
| int cpu_clear; |
| int cpu_mask_status; |
| int cpu_mask_set; |
| int cpu_mask_clear; |
| }; |
| |
| /* Register offsets in the L2 latched interrupt controller */ |
| static const struct brcmstb_intc_init_params l2_edge_intc_init = { |
| .handler = handle_edge_irq, |
| .cpu_status = 0x00, |
| .cpu_clear = 0x08, |
| .cpu_mask_status = 0x0c, |
| .cpu_mask_set = 0x10, |
| .cpu_mask_clear = 0x14 |
| }; |
| |
| /* Register offsets in the L2 level interrupt controller */ |
| static const struct brcmstb_intc_init_params l2_lvl_intc_init = { |
| .handler = handle_level_irq, |
| .cpu_status = 0x00, |
| .cpu_clear = -1, /* Register not present */ |
| .cpu_mask_status = 0x04, |
| .cpu_mask_set = 0x08, |
| .cpu_mask_clear = 0x0C |
| }; |
| |
| /* L2 intc private data structure */ |
| struct brcmstb_l2_intc_data { |
| struct irq_domain *domain; |
| struct irq_chip_generic *gc; |
| int status_offset; |
| int mask_offset; |
| bool can_wake; |
| u32 saved_mask; /* for suspend/resume */ |
| }; |
| |
| /** |
| * brcmstb_l2_mask_and_ack - Mask and ack pending interrupt |
| * @d: irq_data |
| * |
| * Chip has separate enable/disable registers instead of a single mask |
| * register and pending interrupt is acknowledged by setting a bit. |
| * |
| * Note: This function is generic and could easily be added to the |
| * generic irqchip implementation if there ever becomes a will to do so. |
| * Perhaps with a name like irq_gc_mask_disable_and_ack_set(). |
| * |
| * e.g.: https://patchwork.kernel.org/patch/9831047/ |
| */ |
| static void brcmstb_l2_mask_and_ack(struct irq_data *d) |
| { |
| struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); |
| struct irq_chip_type *ct = irq_data_get_chip_type(d); |
| u32 mask = d->mask; |
| |
| irq_gc_lock(gc); |
| irq_reg_writel(gc, mask, ct->regs.disable); |
| *ct->mask_cache &= ~mask; |
| irq_reg_writel(gc, mask, ct->regs.ack); |
| irq_gc_unlock(gc); |
| } |
| |
| static void brcmstb_l2_intc_irq_handle(struct irq_desc *desc) |
| { |
| struct brcmstb_l2_intc_data *b = irq_desc_get_handler_data(desc); |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| unsigned int irq; |
| u32 status; |
| |
| chained_irq_enter(chip, desc); |
| |
| status = irq_reg_readl(b->gc, b->status_offset) & |
| ~(irq_reg_readl(b->gc, b->mask_offset)); |
| |
| if (status == 0) { |
| raw_spin_lock(&desc->lock); |
| handle_bad_irq(desc); |
| raw_spin_unlock(&desc->lock); |
| goto out; |
| } |
| |
| do { |
| irq = ffs(status) - 1; |
| status &= ~(1 << irq); |
| generic_handle_irq(irq_linear_revmap(b->domain, irq)); |
| } while (status); |
| out: |
| /* Don't ack parent before all device writes are done */ |
| wmb(); |
| |
| chained_irq_exit(chip, desc); |
| } |
| |
| static void brcmstb_l2_intc_suspend(struct irq_data *d) |
| { |
| struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); |
| struct irq_chip_type *ct = irq_data_get_chip_type(d); |
| struct brcmstb_l2_intc_data *b = gc->private; |
| unsigned long flags; |
| |
| irq_gc_lock_irqsave(gc, flags); |
| /* Save the current mask */ |
| b->saved_mask = irq_reg_readl(gc, ct->regs.mask); |
| |
| if (b->can_wake) { |
| /* Program the wakeup mask */ |
| irq_reg_writel(gc, ~gc->wake_active, ct->regs.disable); |
| irq_reg_writel(gc, gc->wake_active, ct->regs.enable); |
| } |
| irq_gc_unlock_irqrestore(gc, flags); |
| } |
| |
| static void brcmstb_l2_intc_resume(struct irq_data *d) |
| { |
| struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); |
| struct irq_chip_type *ct = irq_data_get_chip_type(d); |
| struct brcmstb_l2_intc_data *b = gc->private; |
| unsigned long flags; |
| |
| irq_gc_lock_irqsave(gc, flags); |
| if (ct->chip.irq_ack) { |
| /* Clear unmasked non-wakeup interrupts */ |
| irq_reg_writel(gc, ~b->saved_mask & ~gc->wake_active, |
| ct->regs.ack); |
| } |
| |
| /* Restore the saved mask */ |
| irq_reg_writel(gc, b->saved_mask, ct->regs.disable); |
| irq_reg_writel(gc, ~b->saved_mask, ct->regs.enable); |
| irq_gc_unlock_irqrestore(gc, flags); |
| } |
| |
| static int __init brcmstb_l2_intc_of_init(struct device_node *np, |
| struct device_node *parent, |
| const struct brcmstb_intc_init_params |
| *init_params) |
| { |
| unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; |
| unsigned int set = 0; |
| struct brcmstb_l2_intc_data *data; |
| struct irq_chip_type *ct; |
| int ret; |
| unsigned int flags; |
| int parent_irq; |
| void __iomem *base; |
| |
| data = kzalloc(sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| base = of_iomap(np, 0); |
| if (!base) { |
| pr_err("failed to remap intc L2 registers\n"); |
| ret = -ENOMEM; |
| goto out_free; |
| } |
| |
| /* Disable all interrupts by default */ |
| writel(0xffffffff, base + init_params->cpu_mask_set); |
| |
| /* Wakeup interrupts may be retained from S5 (cold boot) */ |
| data->can_wake = of_property_read_bool(np, "brcm,irq-can-wake"); |
| if (!data->can_wake && (init_params->cpu_clear >= 0)) |
| writel(0xffffffff, base + init_params->cpu_clear); |
| |
| parent_irq = irq_of_parse_and_map(np, 0); |
| if (!parent_irq) { |
| pr_err("failed to find parent interrupt\n"); |
| ret = -EINVAL; |
| goto out_unmap; |
| } |
| |
| data->domain = irq_domain_add_linear(np, 32, |
| &irq_generic_chip_ops, NULL); |
| if (!data->domain) { |
| ret = -ENOMEM; |
| goto out_unmap; |
| } |
| |
| /* MIPS chips strapped for BE will automagically configure the |
| * peripheral registers for CPU-native byte order. |
| */ |
| flags = 0; |
| if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) |
| flags |= IRQ_GC_BE_IO; |
| |
| if (init_params->handler == handle_level_irq) |
| set |= IRQ_LEVEL; |
| |
| /* Allocate a single Generic IRQ chip for this node */ |
| ret = irq_alloc_domain_generic_chips(data->domain, 32, 1, |
| np->full_name, init_params->handler, clr, set, flags); |
| if (ret) { |
| pr_err("failed to allocate generic irq chip\n"); |
| goto out_free_domain; |
| } |
| |
| /* Set the IRQ chaining logic */ |
| irq_set_chained_handler_and_data(parent_irq, |
| brcmstb_l2_intc_irq_handle, data); |
| |
| data->gc = irq_get_domain_generic_chip(data->domain, 0); |
| data->gc->reg_base = base; |
| data->gc->private = data; |
| data->status_offset = init_params->cpu_status; |
| data->mask_offset = init_params->cpu_mask_status; |
| |
| ct = data->gc->chip_types; |
| |
| if (init_params->cpu_clear >= 0) { |
| ct->regs.ack = init_params->cpu_clear; |
| ct->chip.irq_ack = irq_gc_ack_set_bit; |
| ct->chip.irq_mask_ack = brcmstb_l2_mask_and_ack; |
| } else { |
| /* No Ack - but still slightly more efficient to define this */ |
| ct->chip.irq_mask_ack = irq_gc_mask_disable_reg; |
| } |
| |
| ct->chip.irq_mask = irq_gc_mask_disable_reg; |
| ct->regs.disable = init_params->cpu_mask_set; |
| ct->regs.mask = init_params->cpu_mask_status; |
| |
| ct->chip.irq_unmask = irq_gc_unmask_enable_reg; |
| ct->regs.enable = init_params->cpu_mask_clear; |
| |
| ct->chip.irq_suspend = brcmstb_l2_intc_suspend; |
| ct->chip.irq_resume = brcmstb_l2_intc_resume; |
| ct->chip.irq_pm_shutdown = brcmstb_l2_intc_suspend; |
| |
| if (data->can_wake) { |
| /* This IRQ chip can wake the system, set all child interrupts |
| * in wake_enabled mask |
| */ |
| data->gc->wake_enabled = 0xffffffff; |
| ct->chip.irq_set_wake = irq_gc_set_wake; |
| } |
| |
| pr_info("registered L2 intc (%pOF, parent irq: %d)\n", np, parent_irq); |
| |
| return 0; |
| |
| out_free_domain: |
| irq_domain_remove(data->domain); |
| out_unmap: |
| iounmap(base); |
| out_free: |
| kfree(data); |
| return ret; |
| } |
| |
| static int __init brcmstb_l2_edge_intc_of_init(struct device_node *np, |
| struct device_node *parent) |
| { |
| return brcmstb_l2_intc_of_init(np, parent, &l2_edge_intc_init); |
| } |
| IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,l2-intc", brcmstb_l2_edge_intc_of_init); |
| |
| static int __init brcmstb_l2_lvl_intc_of_init(struct device_node *np, |
| struct device_node *parent) |
| { |
| return brcmstb_l2_intc_of_init(np, parent, &l2_lvl_intc_init); |
| } |
| IRQCHIP_DECLARE(bcm7271_l2_intc, "brcm,bcm7271-l2-intc", |
| brcmstb_l2_lvl_intc_of_init); |