drivers/xen/efi.c

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

File Facts

System
Linux kernel
Corpus path
drivers/xen/efi.c
Extension
.c
Size
10236 bytes
Lines
356
Domain
Driver Families
Bucket
drivers/xen
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

// SPDX-License-Identifier: GPL-2.0-only
/*
 * EFI support for Xen.
 *
 * Copyright (C) 1999 VA Linux Systems
 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
 * Copyright (C) 1999-2002 Hewlett-Packard Co.
 *	David Mosberger-Tang <davidm@hpl.hp.com>
 *	Stephane Eranian <eranian@hpl.hp.com>
 * Copyright (C) 2005-2008 Intel Co.
 *	Fenghua Yu <fenghua.yu@intel.com>
 *	Bibo Mao <bibo.mao@intel.com>
 *	Chandramouli Narayanan <mouli@linux.intel.com>
 *	Huang Ying <ying.huang@intel.com>
 * Copyright (C) 2011 Novell Co.
 *	Jan Beulich <JBeulich@suse.com>
 * Copyright (C) 2011-2012 Oracle Co.
 *	Liang Tang <liang.tang@oracle.com>
 * Copyright (c) 2014 Oracle Co., Daniel Kiper
 */

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

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

#include <asm/page.h>

#include <asm/xen/hypercall.h>

#define INIT_EFI_OP(name) \
	{.cmd = XENPF_efi_runtime_call, \
	 .u.efi_runtime_call.function = XEN_EFI_##name, \
	 .u.efi_runtime_call.misc = 0}

#define efi_data(op)	(op.u.efi_runtime_call)

static efi_status_t xen_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
{
	struct xen_platform_op op = INIT_EFI_OP(get_time);

	if (HYPERVISOR_platform_op(&op) < 0)
		return EFI_UNSUPPORTED;

	if (tm) {
		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_time.time));
		memcpy(tm, &efi_data(op).u.get_time.time, sizeof(*tm));
	}

	if (tc) {
		tc->resolution = efi_data(op).u.get_time.resolution;
		tc->accuracy = efi_data(op).u.get_time.accuracy;
		tc->sets_to_zero = !!(efi_data(op).misc &
				      XEN_EFI_GET_TIME_SET_CLEARS_NS);
	}

	return efi_data(op).status;
}

static efi_status_t xen_efi_set_time(efi_time_t *tm)
{
	struct xen_platform_op op = INIT_EFI_OP(set_time);

	BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_time));
	memcpy(&efi_data(op).u.set_time, tm, sizeof(*tm));

	if (HYPERVISOR_platform_op(&op) < 0)
		return EFI_UNSUPPORTED;

	return efi_data(op).status;
}

static efi_status_t xen_efi_get_wakeup_time(efi_bool_t *enabled,
					    efi_bool_t *pending,
					    efi_time_t *tm)
{
	struct xen_platform_op op = INIT_EFI_OP(get_wakeup_time);

	if (HYPERVISOR_platform_op(&op) < 0)
		return EFI_UNSUPPORTED;

	if (tm) {
		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_wakeup_time));
		memcpy(tm, &efi_data(op).u.get_wakeup_time, sizeof(*tm));

Annotation

Implementation Notes