static void arm_spe_acpi_register_device()

in arm_pmu_acpi.c [91:134]

• 35 lines of code
• 8 McCabe index (conditional complexity)

static void arm_spe_acpi_register_device(void)
{
	int cpu, hetid, irq, ret;
	bool first = true;
	u16 gsi = 0;

	/*
	 * Sanity check all the GICC tables for the same interrupt number.
	 * For now, we only support homogeneous ACPI/SPE machines.
	 */
	for_each_possible_cpu(cpu) {
		struct acpi_madt_generic_interrupt *gicc;

		gicc = acpi_cpu_get_madt_gicc(cpu);
		if (gicc->header.length < ACPI_MADT_GICC_SPE)
			return;

		if (first) {
			gsi = gicc->spe_interrupt;
			if (!gsi)
				return;
			hetid = find_acpi_cpu_topology_hetero_id(cpu);
			first = false;
		} else if ((gsi != gicc->spe_interrupt) ||
			   (hetid != find_acpi_cpu_topology_hetero_id(cpu))) {
			pr_warn("ACPI: SPE must be homogeneous\n");
			return;
		}
	}

	irq = acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE,
				ACPI_ACTIVE_HIGH);
	if (irq < 0) {
		pr_warn("ACPI: SPE Unable to register interrupt: %d\n", gsi);
		return;
	}

	spe_resources[0].start = irq;
	ret = platform_device_register(&spe_dev);
	if (ret < 0) {
		pr_warn("ACPI: SPE: Unable to register device\n");
		acpi_unregister_gsi(gsi);
	}
}