drivers/firmware/efi/arm-runtime.c

Source file repositories/reference/linux-study-clean/drivers/firmware/efi/arm-runtime.c

File Facts

System
Linux kernel
Corpus path
drivers/firmware/efi/arm-runtime.c
Extension
.c
Size
3878 bytes
Lines
179
Domain
Driver Families
Bucket
drivers/firmware
Inferred role
Driver Families: exported/initcall integration point
Status
integration 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

device_initcall(ptdump_init);

#endif

static bool __init efi_virtmap_init(void)
{
	efi_memory_desc_t *md;

	efi_mm.pgd = pgd_alloc(&efi_mm);
	mm_init_cpumask(&efi_mm);
	init_new_context(NULL, &efi_mm);

	for_each_efi_memory_desc(md) {
		phys_addr_t phys = md->phys_addr;
		int ret;

		if (!(md->attribute & EFI_MEMORY_RUNTIME))
			continue;
		if (md->virt_addr == U64_MAX)
			return false;

		ret = efi_create_mapping(&efi_mm, md);
		if (ret) {
			pr_warn("  EFI remap %pa: failed to create mapping (%d)\n",
				&phys, ret);
			return false;
		}
	}

	if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
		return false;

	return true;
}

/*
 * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
 * non-early mapping of the UEFI system table and virtual mappings for all
 * EFI_MEMORY_RUNTIME regions.
 */
static int __init arm_enable_runtime_services(void)
{
	u64 mapsize;

	if (!efi_enabled(EFI_BOOT)) {
		pr_info("EFI services will not be available.\n");
		return 0;
	}

	efi_memmap_unmap();

	mapsize = efi.memmap.desc_size * efi.memmap.nr_map;

	if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
		pr_err("Failed to remap EFI memory map\n");
		return 0;
	}

	if (efi_soft_reserve_enabled()) {
		efi_memory_desc_t *md;

		for_each_efi_memory_desc(md) {
			u64 md_size = md->num_pages << EFI_PAGE_SHIFT;
			struct resource *res;

			if (!(md->attribute & EFI_MEMORY_SP))
				continue;

			res = kzalloc_obj(*res);
			if (WARN_ON(!res))
				break;

			res->start	= md->phys_addr;
			res->end	= md->phys_addr + md_size - 1;
			res->name	= "Soft Reserved";
			res->flags	= IORESOURCE_MEM;
			res->desc	= IORES_DESC_SOFT_RESERVED;

			insert_resource(&iomem_resource, res);
		}
	}

	if (efi_runtime_disabled()) {
		pr_info("EFI runtime services will be disabled.\n");
		return 0;
	}

	if (efi_enabled(EFI_RUNTIME_SERVICES)) {
		pr_info("EFI runtime services access via paravirt.\n");
		return 0;

Annotation

Implementation Notes