// SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved. */ /* * Driver for interrupt combiners in the Top-level Control and Status * Registers (TCSR) hardware block in Qualcomm Technologies chips. * An interrupt combiner in this block combines a set of interrupts by * OR'ing the individual interrupt signals into a summary interrupt * signal routed to a parent interrupt controller, and provides read- * only, 32-bit registers to query the status of individual interrupts. * The status bit for IRQ n is bit (n % 32) within register (n / 32) * of the given combiner. Thus, each combiner can be described as a set * of register offsets and the number of IRQs managed. */ #define pr_fmt(fmt) "QCOM80B1:" fmt #include <linux/acpi.h> #include <linux/irqchip/chained_irq.h> #include <linux/irqdomain.h> #include <linux/platform_device.h> #define REG_SIZE 32 struct combiner_reg { void __iomem *addr; unsigned long enabled; }; struct combiner { struct irq_domain *domain; int parent_irq; u32 nirqs; u32 nregs; struct combiner_reg regs[]; }; static inline int irq_nr(u32 reg, u32 bit) { return reg * REG_SIZE + bit; } /* * Handler for the cascaded IRQ. */ static void combiner_handle_irq(struct irq_desc *desc) { struct combiner *combiner = irq_desc_get_handler_data(desc); struct irq_chip *chip = irq_desc_get_chip(desc); u32 reg; chained_irq_enter(chip, desc); for (reg = 0; reg < combiner->nregs; reg++) { int virq; int hwirq; u32 bit; u32 status; bit = readl_relaxed(combiner->regs[reg].addr); status = bit & combiner->regs[reg].enabled; if (bit && !status) pr_warn_ratelimited("Unexpected IRQ on CPU%d: (%08x %08lx %p)\n", smp_processor_id(), bit, combiner->regs[reg].enabled, combiner->regs[reg].addr); while (status) { bit = __ffs(status); status &= ~(1 << bit); hwirq = irq_nr(reg, bit); virq = irq_find_mapping(combiner->domain, hwirq); if (virq > 0) generic_handle_irq(virq); } } chained_irq_exit(chip, desc); } static void combiner_irq_chip_mask_irq(struct irq_data *data) { struct combiner *combiner = irq_data_get_irq_chip_data(data); struct combiner_reg *reg = combiner->regs + data->hwirq / REG_SIZE; clear_bit(data->hwirq % REG_SIZE, ®->enabled); } static void combiner_irq_chip_unmask_irq(struct irq_data *data) { struct combiner *combiner = irq_data_get_irq_chip_data(data); struct combiner_reg *reg = combiner->regs + data->hwirq / REG_SIZE; set_bit(data->hwirq % REG_SIZE, ®->enabled); } static struct irq_chip irq_chip = { .irq_mask = combiner_irq_chip_mask_irq, .irq_unmask = combiner_irq_chip_unmask_irq, .name = "qcom-irq-combiner" }; static int combiner_irq_map(struct irq_domain *domain, unsigned int irq, irq_hw_number_t hwirq) { irq_set_chip_and_handler(irq, &irq_chip, handle_level_irq); irq_set_chip_data(irq, domain->host_data); irq_set_noprobe(irq); return 0; } static void combiner_irq_unmap(struct irq_domain *domain, unsigned int irq) { irq_domain_reset_irq_data(irq_get_irq_data(irq)); } static int combiner_irq_translate(struct irq_domain *d, struct irq_fwspec *fws, unsigned long *hwirq, unsigned int *type) { struct combiner *combiner = d->host_data; if (is_acpi_node(fws->fwnode)) { if (WARN_ON((fws->param_count != 2) || (fws->param[0] >= combiner->nirqs) || (fws->param[1] & IORESOURCE_IRQ_LOWEDGE) || (fws->param[1] & IORESOURCE_IRQ_HIGHEDGE))) return -EINVAL; *hwirq = fws->param[0]; *type = fws->param[1]; return 0; } return -EINVAL; } static const struct irq_domain_ops domain_ops = { .map = combiner_irq_map, .unmap = combiner_irq_unmap, .translate = combiner_irq_translate }; static acpi_status count_registers_cb(struct acpi_resource *ares, void *context) { int *count = context; if (ares->type == ACPI_RESOURCE_TYPE_GENERIC_REGISTER) ++(*count); return AE_OK; } static int count_registers(struct platform_device *pdev) { acpi_handle ahandle = ACPI_HANDLE(&pdev->dev); acpi_status status; int count = 0; if (!acpi_has_method(ahandle, METHOD_NAME__CRS)) return -EINVAL; status = acpi_walk_resources(ahandle, METHOD_NAME__CRS, count_registers_cb, &count); if (ACPI_FAILURE(status)) return -EINVAL; return count; } struct get_registers_context { struct device *dev; struct combiner *combiner; int err; }; static acpi_status get_registers_cb(struct acpi_resource *ares, void *context) { struct get_registers_context *ctx = context; struct acpi_resource_generic_register *reg; phys_addr_t paddr; void __iomem *vaddr; if (ares->type != ACPI_RESOURCE_TYPE_GENERIC_REGISTER) return AE_OK; reg = &ares->data.generic_reg; paddr = reg->address; if ((reg->space_id != ACPI_SPACE_MEM) || (reg->bit_offset != 0) || (reg->bit_width > REG_SIZE)) { dev_err(ctx->dev, "Bad register resource @%pa\n", &paddr); ctx->err = -EINVAL; return AE_ERROR; } vaddr = devm_ioremap(ctx->dev, reg->address, REG_SIZE); if (!vaddr) { dev_err(ctx->dev, "Can't map register @%pa\n", &paddr); ctx->err = -ENOMEM; return AE_ERROR; } ctx->combiner->regs[ctx->combiner->nregs].addr = vaddr; ctx->combiner->nirqs += reg->bit_width; ctx->combiner->nregs++; return AE_OK; } static int get_registers(struct platform_device *pdev, struct combiner *comb) { acpi_handle ahandle = ACPI_HANDLE(&pdev->dev); acpi_status status; struct get_registers_context ctx; if (!acpi_has_method(ahandle, METHOD_NAME__CRS)) return -EINVAL; ctx.dev = &pdev->dev; ctx.combiner = comb; ctx.err = 0; status = acpi_walk_resources(ahandle, METHOD_NAME__CRS, get_registers_cb, &ctx); if (ACPI_FAILURE(status)) return ctx.err; return 0; } static int __init combiner_probe(struct platform_device *pdev) { struct combiner *combiner; int nregs; int err; nregs = count_registers(pdev); if (nregs <= 0) { dev_err(&pdev->dev, "Error reading register resources\n"); return -EINVAL; } combiner = devm_kzalloc(&pdev->dev, struct_size(combiner, regs, nregs), GFP_KERNEL); if (!combiner) return -ENOMEM; err = get_registers(pdev, combiner); if (err < 0) return err; combiner->parent_irq = platform_get_irq(pdev, 0); if (combiner->parent_irq <= 0) return -EPROBE_DEFER; combiner->domain = irq_domain_create_linear(pdev->dev.fwnode, combiner->nirqs, &domain_ops, combiner); if (!combiner->domain) /* Errors printed by irq_domain_create_linear */ return -ENODEV; irq_set_chained_handler_and_data(combiner->parent_irq, combiner_handle_irq, combiner); dev_info(&pdev->dev, "Initialized with [p=%d,n=%d,r=%p]\n", combiner->parent_irq, combiner->nirqs, combiner->regs[0].addr); return 0; } static const struct acpi_device_id qcom_irq_combiner_ids[] = { { "QCOM80B1", }, { } }; static struct platform_driver qcom_irq_combiner_probe = { .driver = { .name = "qcom-irq-combiner", .acpi_match_table = ACPI_PTR(qcom_irq_combiner_ids), }, .probe = combiner_probe, }; builtin_platform_driver(qcom_irq_combiner_probe);