u-boot/arch/x86/cpu/qemu/fw_cfg.c
Miao Yan fa287b1580 x86: qemu: add the ability to load and link ACPI tables from QEMU
This patch adds the ability to load and link ACPI tables provided by QEMU.
QEMU tells guests how to load and patch ACPI tables through its fw_cfg
interface, by adding a firmware file 'etc/table-loader'. Guests are
supposed to parse this file and execute corresponding QEMU commands.

Signed-off-by: Miao Yan <yanmiaobest@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2016-01-28 13:53:30 +08:00

571 lines
14 KiB
C

/*
* (C) Copyright 2015 Miao Yan <yanmiaoebst@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <command.h>
#include <errno.h>
#include <malloc.h>
#include <asm/io.h>
#include <asm/fw_cfg.h>
#include <asm/tables.h>
#include <asm/e820.h>
#include <linux/list.h>
#include <memalign.h>
static bool fwcfg_present;
static bool fwcfg_dma_present;
static LIST_HEAD(fw_list);
/* Read configuration item using fw_cfg PIO interface */
static void qemu_fwcfg_read_entry_pio(uint16_t entry,
uint32_t size, void *address)
{
uint32_t i = 0;
uint8_t *data = address;
/*
* writting FW_CFG_INVALID will cause read operation to resume at
* last offset, otherwise read will start at offset 0
*/
if (entry != FW_CFG_INVALID)
outw(entry, FW_CONTROL_PORT);
while (size--)
data[i++] = inb(FW_DATA_PORT);
}
/* Read configuration item using fw_cfg DMA interface */
static void qemu_fwcfg_read_entry_dma(uint16_t entry,
uint32_t size, void *address)
{
struct fw_cfg_dma_access dma;
dma.length = cpu_to_be32(size);
dma.address = cpu_to_be64((uintptr_t)address);
dma.control = cpu_to_be32(FW_CFG_DMA_READ);
/*
* writting FW_CFG_INVALID will cause read operation to resume at
* last offset, otherwise read will start at offset 0
*/
if (entry != FW_CFG_INVALID)
dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
barrier();
debug("qemu_fwcfg_dma_read_entry: addr %p, length %u control 0x%x\n",
address, size, be32_to_cpu(dma.control));
outl(cpu_to_be32((uint32_t)&dma), FW_DMA_PORT_HIGH);
while (be32_to_cpu(dma.control) & ~FW_CFG_DMA_ERROR)
__asm__ __volatile__ ("pause");
}
static bool qemu_fwcfg_present(void)
{
uint32_t qemu;
qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
return be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE;
}
static bool qemu_fwcfg_dma_present(void)
{
uint8_t dma_enabled;
qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
if (dma_enabled & FW_CFG_DMA_ENABLED)
return true;
return false;
}
static void qemu_fwcfg_read_entry(uint16_t entry,
uint32_t length, void *address)
{
if (fwcfg_dma_present)
qemu_fwcfg_read_entry_dma(entry, length, address);
else
qemu_fwcfg_read_entry_pio(entry, length, address);
}
int qemu_fwcfg_online_cpus(void)
{
uint16_t nb_cpus;
if (!fwcfg_present)
return -ENODEV;
qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
return le16_to_cpu(nb_cpus);
}
/*
* This function prepares kernel for zboot. It loads kernel data
* to 'load_addr', initrd to 'initrd_addr' and kernel command
* line using qemu fw_cfg interface.
*/
static int qemu_fwcfg_setup_kernel(void *load_addr, void *initrd_addr)
{
char *data_addr;
uint32_t setup_size, kernel_size, cmdline_size, initrd_size;
qemu_fwcfg_read_entry(FW_CFG_SETUP_SIZE, 4, &setup_size);
qemu_fwcfg_read_entry(FW_CFG_KERNEL_SIZE, 4, &kernel_size);
if (setup_size == 0 || kernel_size == 0) {
printf("warning: no kernel available\n");
return -1;
}
data_addr = load_addr;
qemu_fwcfg_read_entry(FW_CFG_SETUP_DATA,
le32_to_cpu(setup_size), data_addr);
data_addr += le32_to_cpu(setup_size);
qemu_fwcfg_read_entry(FW_CFG_KERNEL_DATA,
le32_to_cpu(kernel_size), data_addr);
data_addr += le32_to_cpu(kernel_size);
data_addr = initrd_addr;
qemu_fwcfg_read_entry(FW_CFG_INITRD_SIZE, 4, &initrd_size);
if (initrd_size == 0) {
printf("warning: no initrd available\n");
} else {
qemu_fwcfg_read_entry(FW_CFG_INITRD_DATA,
le32_to_cpu(initrd_size), data_addr);
data_addr += le32_to_cpu(initrd_size);
}
qemu_fwcfg_read_entry(FW_CFG_CMDLINE_SIZE, 4, &cmdline_size);
if (cmdline_size) {
qemu_fwcfg_read_entry(FW_CFG_CMDLINE_DATA,
le32_to_cpu(cmdline_size), data_addr);
/*
* if kernel cmdline only contains '\0', (e.g. no -append
* when invoking qemu), do not update bootargs
*/
if (*data_addr != '\0') {
if (setenv("bootargs", data_addr) < 0)
printf("warning: unable to change bootargs\n");
}
}
printf("loading kernel to address %p size %x", load_addr,
le32_to_cpu(kernel_size));
if (initrd_size)
printf(" initrd %p size %x\n",
initrd_addr,
le32_to_cpu(initrd_size));
else
printf("\n");
return 0;
}
static int qemu_fwcfg_read_firmware_list(void)
{
int i;
uint32_t count;
struct fw_file *file;
struct list_head *entry;
/* don't read it twice */
if (!list_empty(&fw_list))
return 0;
qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
if (!count)
return 0;
count = be32_to_cpu(count);
for (i = 0; i < count; i++) {
file = malloc(sizeof(*file));
if (!file) {
printf("error: allocating resource\n");
goto err;
}
qemu_fwcfg_read_entry(FW_CFG_INVALID,
sizeof(struct fw_cfg_file), &file->cfg);
file->addr = 0;
list_add_tail(&file->list, &fw_list);
}
return 0;
err:
list_for_each(entry, &fw_list) {
file = list_entry(entry, struct fw_file, list);
free(file);
}
return -ENOMEM;
}
#ifdef CONFIG_QEMU_ACPI_TABLE
static struct fw_file *qemu_fwcfg_find_file(const char *name)
{
struct list_head *entry;
struct fw_file *file;
list_for_each(entry, &fw_list) {
file = list_entry(entry, struct fw_file, list);
if (!strcmp(file->cfg.name, name))
return file;
}
return NULL;
}
/*
* This function allocates memory for ACPI tables
*
* @entry : BIOS linker command entry which tells where to allocate memory
* (either high memory or low memory)
* @addr : The address that should be used for low memory allcation. If the
* memory allocation request is 'ZONE_HIGH' then this parameter will
* be ignored.
* @return: 0 on success, or negative value on failure
*/
static int bios_linker_allocate(struct bios_linker_entry *entry,
unsigned long *addr)
{
uint32_t size, align;
struct fw_file *file;
unsigned long aligned_addr;
align = le32_to_cpu(entry->alloc.align);
/* align must be power of 2 */
if (align & (align - 1)) {
printf("error: wrong alignment %u\n", align);
return -EINVAL;
}
file = qemu_fwcfg_find_file(entry->alloc.file);
if (!file) {
printf("error: can't find file %s\n", entry->alloc.file);
return -ENOENT;
}
size = be32_to_cpu(file->cfg.size);
/*
* ZONE_HIGH means we need to allocate from high memory, since
* malloc space is already at the end of RAM, so we directly use it.
* If allocation zone is ZONE_FSEG, then we use the 'addr' passed
* in which is low memory
*/
if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH) {
aligned_addr = (unsigned long)memalign(align, size);
if (!aligned_addr) {
printf("error: allocating resource\n");
return -ENOMEM;
}
} else if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG) {
aligned_addr = ALIGN(*addr, align);
} else {
printf("error: invalid allocation zone\n");
return -EINVAL;
}
debug("bios_linker_allocate: allocate file %s, size %u, zone %d, align %u, addr 0x%lx\n",
file->cfg.name, size, entry->alloc.zone, align, aligned_addr);
qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
size, (void *)aligned_addr);
file->addr = aligned_addr;
/* adjust address for low memory allocation */
if (entry->alloc.zone == BIOS_LINKER_LOADER_ALLOC_ZONE_FSEG)
*addr = (aligned_addr + size);
return 0;
}
/*
* This function patches ACPI tables previously loaded
* by bios_linker_allocate()
*
* @entry : BIOS linker command entry which tells how to patch
* ACPI tables
* @return: 0 on success, or negative value on failure
*/
static int bios_linker_add_pointer(struct bios_linker_entry *entry)
{
struct fw_file *dest, *src;
uint32_t offset = le32_to_cpu(entry->pointer.offset);
uint64_t pointer = 0;
dest = qemu_fwcfg_find_file(entry->pointer.dest_file);
if (!dest || !dest->addr)
return -ENOENT;
src = qemu_fwcfg_find_file(entry->pointer.src_file);
if (!src || !src->addr)
return -ENOENT;
debug("bios_linker_add_pointer: dest->addr 0x%lx, src->addr 0x%lx, offset 0x%x size %u, 0x%llx\n",
dest->addr, src->addr, offset, entry->pointer.size, pointer);
memcpy(&pointer, (char *)dest->addr + offset, entry->pointer.size);
pointer = le64_to_cpu(pointer);
pointer += (unsigned long)src->addr;
pointer = cpu_to_le64(pointer);
memcpy((char *)dest->addr + offset, &pointer, entry->pointer.size);
return 0;
}
/*
* This function updates checksum fields of ACPI tables previously loaded
* by bios_linker_allocate()
*
* @entry : BIOS linker command entry which tells where to update ACPI table
* checksums
* @return: 0 on success, or negative value on failure
*/
static int bios_linker_add_checksum(struct bios_linker_entry *entry)
{
struct fw_file *file;
uint8_t *data, cksum = 0;
uint8_t *cksum_start;
file = qemu_fwcfg_find_file(entry->cksum.file);
if (!file || !file->addr)
return -ENOENT;
data = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.offset));
cksum_start = (uint8_t *)(file->addr + le32_to_cpu(entry->cksum.start));
cksum = table_compute_checksum(cksum_start,
le32_to_cpu(entry->cksum.length));
*data = cksum;
return 0;
}
unsigned install_e820_map(unsigned max_entries, struct e820entry *entries)
{
entries[0].addr = 0;
entries[0].size = ISA_START_ADDRESS;
entries[0].type = E820_RAM;
entries[1].addr = ISA_START_ADDRESS;
entries[1].size = ISA_END_ADDRESS - ISA_START_ADDRESS;
entries[1].type = E820_RESERVED;
/*
* since we use memalign(malloc) to allocate high memory for
* storing ACPI tables, we need to reserve them in e820 tables,
* otherwise kernel will reclaim them and data will be corrupted
*/
entries[2].addr = ISA_END_ADDRESS;
entries[2].size = gd->relocaddr - TOTAL_MALLOC_LEN - ISA_END_ADDRESS;
entries[2].type = E820_RAM;
/* for simplicity, reserve entire malloc space */
entries[3].addr = gd->relocaddr - TOTAL_MALLOC_LEN;
entries[3].size = TOTAL_MALLOC_LEN;
entries[3].type = E820_RESERVED;
entries[4].addr = gd->relocaddr;
entries[4].size = gd->ram_size - gd->relocaddr;
entries[4].type = E820_RESERVED;
entries[5].addr = CONFIG_PCIE_ECAM_BASE;
entries[5].size = CONFIG_PCIE_ECAM_SIZE;
entries[5].type = E820_RESERVED;
return 6;
}
/* This function loads and patches ACPI tables provided by QEMU */
unsigned long write_acpi_tables(unsigned long addr)
{
int i, ret = 0;
struct fw_file *file;
struct bios_linker_entry *table_loader;
struct bios_linker_entry *entry;
uint32_t size;
struct list_head *list;
/* make sure fw_list is loaded */
ret = qemu_fwcfg_read_firmware_list();
if (ret) {
printf("error: can't read firmware file list\n");
return addr;
}
file = qemu_fwcfg_find_file("etc/table-loader");
if (!file) {
printf("error: can't find etc/table-loader\n");
return addr;
}
size = be32_to_cpu(file->cfg.size);
if ((size % sizeof(*entry)) != 0) {
printf("error: table-loader maybe corrupted\n");
return addr;
}
table_loader = malloc(size);
if (!table_loader) {
printf("error: no memory for table-loader\n");
return addr;
}
qemu_fwcfg_read_entry(be16_to_cpu(file->cfg.select),
size, table_loader);
for (i = 0; i < (size / sizeof(*entry)); i++) {
entry = table_loader + i;
switch (le32_to_cpu(entry->command)) {
case BIOS_LINKER_LOADER_COMMAND_ALLOCATE:
ret = bios_linker_allocate(entry, &addr);
if (ret)
goto out;
break;
case BIOS_LINKER_LOADER_COMMAND_ADD_POINTER:
ret = bios_linker_add_pointer(entry);
if (ret)
goto out;
break;
case BIOS_LINKER_LOADER_COMMAND_ADD_CHECKSUM:
ret = bios_linker_add_checksum(entry);
if (ret)
goto out;
break;
default:
break;
}
}
out:
if (ret) {
list_for_each(list, &fw_list) {
file = list_entry(list, struct fw_file, list);
if (file->addr)
free((void *)file->addr);
}
}
free(table_loader);
return addr;
}
#endif
static int qemu_fwcfg_list_firmware(void)
{
int ret;
struct list_head *entry;
struct fw_file *file;
/* make sure fw_list is loaded */
ret = qemu_fwcfg_read_firmware_list();
if (ret)
return ret;
list_for_each(entry, &fw_list) {
file = list_entry(entry, struct fw_file, list);
printf("%-56s\n", file->cfg.name);
}
return 0;
}
void qemu_fwcfg_init(void)
{
fwcfg_present = qemu_fwcfg_present();
if (fwcfg_present)
fwcfg_dma_present = qemu_fwcfg_dma_present();
}
static int qemu_fwcfg_do_list(cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[])
{
if (qemu_fwcfg_list_firmware() < 0)
return CMD_RET_FAILURE;
return 0;
}
static int qemu_fwcfg_do_cpus(cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[])
{
int ret = qemu_fwcfg_online_cpus();
if (ret < 0) {
printf("QEMU fw_cfg interface not found\n");
return CMD_RET_FAILURE;
}
printf("%d cpu(s) online\n", qemu_fwcfg_online_cpus());
return 0;
}
static int qemu_fwcfg_do_load(cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[])
{
char *env;
void *load_addr;
void *initrd_addr;
env = getenv("loadaddr");
load_addr = env ?
(void *)simple_strtoul(env, NULL, 16) :
(void *)CONFIG_LOADADDR;
env = getenv("ramdiskaddr");
initrd_addr = env ?
(void *)simple_strtoul(env, NULL, 16) :
(void *)CONFIG_RAMDISK_ADDR;
if (argc == 2) {
load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
initrd_addr = (void *)simple_strtoul(argv[1], NULL, 16);
} else if (argc == 1) {
load_addr = (void *)simple_strtoul(argv[0], NULL, 16);
}
return qemu_fwcfg_setup_kernel(load_addr, initrd_addr);
}
static cmd_tbl_t fwcfg_commands[] = {
U_BOOT_CMD_MKENT(list, 0, 1, qemu_fwcfg_do_list, "", ""),
U_BOOT_CMD_MKENT(cpus, 0, 1, qemu_fwcfg_do_cpus, "", ""),
U_BOOT_CMD_MKENT(load, 2, 1, qemu_fwcfg_do_load, "", ""),
};
static int do_qemu_fw(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int ret;
cmd_tbl_t *fwcfg_cmd;
if (!fwcfg_present) {
printf("QEMU fw_cfg interface not found\n");
return CMD_RET_USAGE;
}
fwcfg_cmd = find_cmd_tbl(argv[1], fwcfg_commands,
ARRAY_SIZE(fwcfg_commands));
argc -= 2;
argv += 2;
if (!fwcfg_cmd || argc > fwcfg_cmd->maxargs)
return CMD_RET_USAGE;
ret = fwcfg_cmd->cmd(fwcfg_cmd, flag, argc, argv);
return cmd_process_error(fwcfg_cmd, ret);
}
U_BOOT_CMD(
qfw, 4, 1, do_qemu_fw,
"QEMU firmware interface",
"<command>\n"
" - list : print firmware(s) currently loaded\n"
" - cpus : print online cpu number\n"
" - load <kernel addr> <initrd addr> : load kernel and initrd (if any), and setup for zboot\n"
)