101 lines
2.3 KiB
C
101 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright 2007-2010 Red Hat, Inc.
|
|
* by Peter Jones <pjones@redhat.com>
|
|
* Copyright 2007 IBM, Inc.
|
|
* by Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
|
|
* Copyright 2008
|
|
* by Konrad Rzeszutek <ketuzsezr@darnok.org>
|
|
*
|
|
* This code finds the iSCSI Boot Format Table.
|
|
*/
|
|
|
|
#include <linux/memblock.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/ctype.h>
|
|
#include <linux/device.h>
|
|
#include <linux/efi.h>
|
|
#include <linux/err.h>
|
|
#include <linux/init.h>
|
|
#include <linux/limits.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/stat.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/iscsi_ibft.h>
|
|
|
|
#include <asm/mmzone.h>
|
|
|
|
/*
|
|
* Physical location of iSCSI Boot Format Table.
|
|
*/
|
|
phys_addr_t ibft_phys_addr;
|
|
EXPORT_SYMBOL_GPL(ibft_phys_addr);
|
|
|
|
static const struct {
|
|
char *sign;
|
|
} ibft_signs[] = {
|
|
{ "iBFT" },
|
|
{ "BIFT" }, /* Broadcom iSCSI Offload */
|
|
};
|
|
|
|
#define IBFT_SIGN_LEN 4
|
|
#define VGA_MEM 0xA0000 /* VGA buffer */
|
|
#define VGA_SIZE 0x20000 /* 128kB */
|
|
|
|
/*
|
|
* Routine used to find and reserve the iSCSI Boot Format Table
|
|
*/
|
|
void __init reserve_ibft_region(void)
|
|
{
|
|
unsigned long pos, virt_pos = 0;
|
|
unsigned int len = 0;
|
|
void *virt = NULL;
|
|
int i;
|
|
|
|
ibft_phys_addr = 0;
|
|
|
|
/* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will
|
|
* only use ACPI for this
|
|
*/
|
|
if (efi_enabled(EFI_BOOT))
|
|
return;
|
|
|
|
for (pos = IBFT_START; pos < IBFT_END; pos += 16) {
|
|
/* The table can't be inside the VGA BIOS reserved space,
|
|
* so skip that area */
|
|
if (pos == VGA_MEM)
|
|
pos += VGA_SIZE;
|
|
|
|
/* Map page by page */
|
|
if (offset_in_page(pos) == 0) {
|
|
if (virt)
|
|
early_memunmap(virt, PAGE_SIZE);
|
|
virt = early_memremap_ro(pos, PAGE_SIZE);
|
|
virt_pos = pos;
|
|
}
|
|
|
|
for (i = 0; i < ARRAY_SIZE(ibft_signs); i++) {
|
|
if (memcmp(virt + (pos - virt_pos), ibft_signs[i].sign,
|
|
IBFT_SIGN_LEN) == 0) {
|
|
unsigned long *addr =
|
|
(unsigned long *)(virt + pos - virt_pos + 4);
|
|
len = *addr;
|
|
/* if the length of the table extends past 1M,
|
|
* the table cannot be valid. */
|
|
if (pos + len <= (IBFT_END-1)) {
|
|
ibft_phys_addr = pos;
|
|
memblock_reserve(ibft_phys_addr, PAGE_ALIGN(len));
|
|
pr_info("iBFT found at %pa.\n", &ibft_phys_addr);
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
out:
|
|
early_memunmap(virt, PAGE_SIZE);
|
|
}
|