blob: 1804b27f9632a12b4ed9877c8e97bce35177a2be [file] [log] [blame]
/*
* Copyright (c) 2014 Oracle Co., Daniel Kiper
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#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>
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 = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
.con_out_handle = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
.con_out = EFI_INVALID_TABLE_ADDR, /* 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. */
efi.get_time = xen_efi_get_time;
efi.set_time = xen_efi_set_time;
efi.get_wakeup_time = xen_efi_get_wakeup_time;
efi.set_wakeup_time = xen_efi_set_wakeup_time;
efi.get_variable = xen_efi_get_variable;
efi.get_next_variable = xen_efi_get_next_variable;
efi.set_variable = xen_efi_set_variable;
efi.query_variable_info = xen_efi_query_variable_info;
efi.update_capsule = xen_efi_update_capsule;
efi.query_capsule_caps = xen_efi_query_capsule_caps;
efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
efi.reset_system = xen_efi_reset_system;
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)
efi.runtime_version = info->version;
return &efi_systab_xen;
}
/*
* Determine whether we're in secure boot mode.
*
* Please keep the logic in sync with
* drivers/firmware/efi/libstub/secureboot.c:efi_get_secureboot().
*/
static enum efi_secureboot_mode xen_efi_get_secureboot(void)
{
static efi_guid_t efi_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
static efi_guid_t shim_guid = EFI_SHIM_LOCK_GUID;
efi_status_t status;
u8 moksbstate, secboot, setupmode;
unsigned long size;
size = sizeof(secboot);
status = efi.get_variable(L"SecureBoot", &efi_variable_guid,
NULL, &size, &secboot);
if (status == EFI_NOT_FOUND)
return efi_secureboot_mode_disabled;
if (status != EFI_SUCCESS)
goto out_efi_err;
size = sizeof(setupmode);
status = efi.get_variable(L"SetupMode", &efi_variable_guid,
NULL, &size, &setupmode);
if (status != EFI_SUCCESS)
goto out_efi_err;
if (secboot == 0 || setupmode == 1)
return efi_secureboot_mode_disabled;
/* See if a user has put the shim into insecure mode. */
size = sizeof(moksbstate);
status = efi.get_variable(L"MokSBStateRT", &shim_guid,
NULL, &size, &moksbstate);
/* If it fails, we don't care why. Default to secure. */
if (status != EFI_SUCCESS)
goto secure_boot_enabled;
if (moksbstate == 1)
return efi_secureboot_mode_disabled;
secure_boot_enabled:
pr_info("UEFI Secure Boot is enabled.\n");
return efi_secureboot_mode_enabled;
out_efi_err:
pr_err("Could not determine UEFI Secure Boot status.\n");
return efi_secureboot_mode_unknown;
}
void __init xen_efi_init(void)
{
efi_system_table_t *efi_systab_xen;
efi_systab_xen = xen_efi_probe();
if (efi_systab_xen == NULL)
return;
strncpy((char *)&boot_params.efi_info.efi_loader_signature, "Xen",
sizeof(boot_params.efi_info.efi_loader_signature));
boot_params.efi_info.efi_systab = (__u32)__pa(efi_systab_xen);
boot_params.efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32);
boot_params.secure_boot = xen_efi_get_secureboot();
set_bit(EFI_BOOT, &efi.flags);
set_bit(EFI_PARAVIRT, &efi.flags);
set_bit(EFI_64BIT, &efi.flags);
}