drivers/irqchip/irq-aclint-sswi.c

Source file repositories/reference/linux-study-clean/drivers/irqchip/irq-aclint-sswi.c

File Facts

System
Linux kernel
Corpus path
drivers/irqchip/irq-aclint-sswi.c
Extension
.c
Size
5083 bytes
Lines
212
Domain
Driver Families
Bucket
drivers/irqchip
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (rc) {
			pr_warn("%pfwP: hart index [%d] not found\n", fwnode, i);
			return -EINVAL;
		}
		per_cpu(sswi_cpu_regs, cpu) = reg + hart_index * 4;
	}

	pr_info("%pfwP: register %u CPU%s\n", fwnode, contexts, str_plural(contexts));

	return 0;
}

static int __init aclint_sswi_probe(struct fwnode_handle *fwnode)
{
	struct irq_domain *domain;
	void __iomem *reg;
	int virq, rc;

	if (!is_of_node(fwnode))
		return -EINVAL;

	reg = of_io_request_and_map(to_of_node(fwnode), 0, NULL);
	if (IS_ERR(reg)) {
		pr_err("%pfwP: Failed to map MMIO region\n", fwnode);
		return PTR_ERR(reg);
	}

	/* Parse SSWI setting */
	rc = aclint_sswi_parse_irq(fwnode, reg);
	if (rc < 0)
		return rc;

	/* If mulitple SSWI devices are present, do not register irq again */
	if (sswi_ipi_virq)
		return 0;

	/* Find riscv intc domain and create IPI irq mapping */
	domain = irq_find_matching_fwnode(riscv_get_intc_hwnode(), DOMAIN_BUS_ANY);
	if (!domain) {
		pr_err("%pfwP: Failed to find INTC domain\n", fwnode);
		return -ENOENT;
	}

	sswi_ipi_virq = irq_create_mapping(domain, RV_IRQ_SOFT);
	if (!sswi_ipi_virq) {
		pr_err("unable to create ACLINT SSWI IRQ mapping\n");
		return -ENOMEM;
	}

	/* Register SSWI irq and handler */
	virq = ipi_mux_create(BITS_PER_BYTE, aclint_sswi_ipi_send);
	if (virq <= 0) {
		pr_err("unable to create muxed IPIs\n");
		irq_dispose_mapping(sswi_ipi_virq);
		return virq < 0 ? virq : -ENOMEM;
	}

	irq_set_chained_handler(sswi_ipi_virq, aclint_sswi_ipi_handle);

	cpuhp_setup_state(CPUHP_AP_IRQ_ACLINT_SSWI_STARTING,
			  "irqchip/aclint-sswi:starting",
			  aclint_sswi_starting_cpu,
			  aclint_sswi_dying_cpu);

	riscv_ipi_set_virq_range(virq, BITS_PER_BYTE);

	return 0;
}

/* generic/MIPS variant */
static int __init generic_aclint_sswi_probe(struct fwnode_handle *fwnode)
{
	int rc;

	rc = aclint_sswi_probe(fwnode);
	if (rc)
		return rc;

	/* Announce that SSWI is providing IPIs */
	pr_info("providing IPIs using ACLINT SSWI\n");

	return 0;
}

static int __init generic_aclint_sswi_early_probe(struct device_node *node,
						  struct device_node *parent)
{
	return generic_aclint_sswi_probe(&node->fwnode);
}
IRQCHIP_DECLARE(mips_p8700_sswi, "mips,p8700-aclint-sswi", generic_aclint_sswi_early_probe);

Annotation

Implementation Notes