arch/x86/xen/efi.c

Source file repositories/reference/linux-study-clean/arch/x86/xen/efi.c

File Facts

System
Linux kernel
Corpus path
arch/x86/xen/efi.c
Extension
.c
Size
4415 bytes
Lines
152
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2014 Oracle Co., Daniel Kiper
 */

#include <linux/bitops.h>
#include <linux/efi.h>
#include <linux/init.h>
#include <linux/string.h>

#include <xen/xen.h>
#include <xen/xen-ops.h>
#include <xen/interface/platform.h>

#include <asm/page.h>
#include <asm/setup.h>
#include <asm/xen/hypercall.h>

#include "xen-ops.h"

static efi_char16_t vendor[100] __initdata;

static efi_system_table_t efi_systab_xen __initdata = {
	.hdr = {
		.signature	= EFI_SYSTEM_TABLE_SIGNATURE,
		.revision	= 0, /* Initialized later. */
		.headersize	= 0, /* Ignored by Linux Kernel. */
		.crc32		= 0, /* Ignored by Linux Kernel. */
		.reserved	= 0
	},
	.fw_vendor	= EFI_INVALID_TABLE_ADDR, /* Initialized later. */
	.fw_revision	= 0,			  /* Initialized later. */
	.con_in_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.con_in		= NULL,			  /* Not used under Xen. */
	.con_out_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.con_out	= NULL, 		  /* Not used under Xen. */
	.stderr_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.stderr		= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.runtime	= (efi_runtime_services_t *)EFI_INVALID_TABLE_ADDR,
						  /* Not used under Xen. */
	.boottime	= (efi_boot_services_t *)EFI_INVALID_TABLE_ADDR,
						  /* Not used under Xen. */
	.nr_tables	= 0,			  /* Initialized later. */
	.tables		= EFI_INVALID_TABLE_ADDR  /* Initialized later. */
};

static efi_system_table_t __init *xen_efi_probe(void)
{
	struct xen_platform_op op = {
		.cmd = XENPF_firmware_info,
		.u.firmware_info = {
			.type = XEN_FW_EFI_INFO,
			.index = XEN_FW_EFI_CONFIG_TABLE
		}
	};
	union xenpf_efi_info *info = &op.u.firmware_info.u.efi_info;

	if (!xen_initial_domain() || HYPERVISOR_platform_op(&op) < 0)
		return NULL;

	/* Here we know that Xen runs on EFI platform. */
	xen_efi_runtime_setup();

	efi_systab_xen.tables = info->cfg.addr;
	efi_systab_xen.nr_tables = info->cfg.nent;

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_VENDOR;
	info->vendor.bufsz = sizeof(vendor);
	set_xen_guest_handle(info->vendor.name, vendor);

	if (HYPERVISOR_platform_op(&op) == 0) {
		efi_systab_xen.fw_vendor = __pa_symbol(vendor);
		efi_systab_xen.fw_revision = info->vendor.revision;
	} else
		efi_systab_xen.fw_vendor = __pa_symbol(L"UNKNOWN");

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_VERSION;

	if (HYPERVISOR_platform_op(&op) == 0)
		efi_systab_xen.hdr.revision = info->version;

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_RT_VERSION;

	if (HYPERVISOR_platform_op(&op) == 0)

Annotation

Implementation Notes