qemu/hw/arm_boot.c
Peter Maydell fc53b7d4b7 arm_boot: Change initrd load address to "halfway through RAM"
To avoid continually having to bump the initrd load address
to account for larger kernel images, put the initrd halfway
through RAM. This allows large kernels on new boards with lots
of RAM to work OK, without breaking existing usecases for
boards with only 32MB of RAM.

Note that this change fixes in passing a bug where we were
passing an overly large max_size to load_image_targphys()
for the initrd, which meant that we wouldn't correctly refuse
to load an enormous initrd that didn't actually fit into RAM.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Igor Mitsyanko <i.mitsyanko@samsung.com>
Tested-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2012-11-01 17:04:11 +01:00

466 lines
14 KiB
C

/*
* ARM kernel loader.
*
* Copyright (c) 2006-2007 CodeSourcery.
* Written by Paul Brook
*
* This code is licensed under the GPL.
*/
#include "config.h"
#include "hw.h"
#include "arm-misc.h"
#include "sysemu.h"
#include "boards.h"
#include "loader.h"
#include "elf.h"
#include "device_tree.h"
#define KERNEL_ARGS_ADDR 0x100
#define KERNEL_LOAD_ADDR 0x00010000
/* The worlds second smallest bootloader. Set r0-r2, then jump to kernel. */
static uint32_t bootloader[] = {
0xe3a00000, /* mov r0, #0 */
0xe59f1004, /* ldr r1, [pc, #4] */
0xe59f2004, /* ldr r2, [pc, #4] */
0xe59ff004, /* ldr pc, [pc, #4] */
0, /* Board ID */
0, /* Address of kernel args. Set by integratorcp_init. */
0 /* Kernel entry point. Set by integratorcp_init. */
};
/* Handling for secondary CPU boot in a multicore system.
* Unlike the uniprocessor/primary CPU boot, this is platform
* dependent. The default code here is based on the secondary
* CPU boot protocol used on realview/vexpress boards, with
* some parameterisation to increase its flexibility.
* QEMU platform models for which this code is not appropriate
* should override write_secondary_boot and secondary_cpu_reset_hook
* instead.
*
* This code enables the interrupt controllers for the secondary
* CPUs and then puts all the secondary CPUs into a loop waiting
* for an interprocessor interrupt and polling a configurable
* location for the kernel secondary CPU entry point.
*/
static uint32_t smpboot[] = {
0xe59f201c, /* ldr r2, gic_cpu_if */
0xe59f001c, /* ldr r0, startaddr */
0xe3a01001, /* mov r1, #1 */
0xe5821000, /* str r1, [r2] */
0xe320f003, /* wfi */
0xe5901000, /* ldr r1, [r0] */
0xe1110001, /* tst r1, r1 */
0x0afffffb, /* beq <wfi> */
0xe12fff11, /* bx r1 */
0, /* gic_cpu_if: base address of GIC CPU interface */
0 /* bootreg: Boot register address is held here */
};
static void default_write_secondary(ARMCPU *cpu,
const struct arm_boot_info *info)
{
int n;
smpboot[ARRAY_SIZE(smpboot) - 1] = info->smp_bootreg_addr;
smpboot[ARRAY_SIZE(smpboot) - 2] = info->gic_cpu_if_addr;
for (n = 0; n < ARRAY_SIZE(smpboot); n++) {
smpboot[n] = tswap32(smpboot[n]);
}
rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),
info->smp_loader_start);
}
static void default_reset_secondary(ARMCPU *cpu,
const struct arm_boot_info *info)
{
CPUARMState *env = &cpu->env;
stl_phys_notdirty(info->smp_bootreg_addr, 0);
env->regs[15] = info->smp_loader_start;
}
#define WRITE_WORD(p, value) do { \
stl_phys_notdirty(p, value); \
p += 4; \
} while (0)
static void set_kernel_args(const struct arm_boot_info *info)
{
int initrd_size = info->initrd_size;
hwaddr base = info->loader_start;
hwaddr p;
p = base + KERNEL_ARGS_ADDR;
/* ATAG_CORE */
WRITE_WORD(p, 5);
WRITE_WORD(p, 0x54410001);
WRITE_WORD(p, 1);
WRITE_WORD(p, 0x1000);
WRITE_WORD(p, 0);
/* ATAG_MEM */
/* TODO: handle multiple chips on one ATAG list */
WRITE_WORD(p, 4);
WRITE_WORD(p, 0x54410002);
WRITE_WORD(p, info->ram_size);
WRITE_WORD(p, info->loader_start);
if (initrd_size) {
/* ATAG_INITRD2 */
WRITE_WORD(p, 4);
WRITE_WORD(p, 0x54420005);
WRITE_WORD(p, info->initrd_start);
WRITE_WORD(p, initrd_size);
}
if (info->kernel_cmdline && *info->kernel_cmdline) {
/* ATAG_CMDLINE */
int cmdline_size;
cmdline_size = strlen(info->kernel_cmdline);
cpu_physical_memory_write(p + 8, (void *)info->kernel_cmdline,
cmdline_size + 1);
cmdline_size = (cmdline_size >> 2) + 1;
WRITE_WORD(p, cmdline_size + 2);
WRITE_WORD(p, 0x54410009);
p += cmdline_size * 4;
}
if (info->atag_board) {
/* ATAG_BOARD */
int atag_board_len;
uint8_t atag_board_buf[0x1000];
atag_board_len = (info->atag_board(info, atag_board_buf) + 3) & ~3;
WRITE_WORD(p, (atag_board_len + 8) >> 2);
WRITE_WORD(p, 0x414f4d50);
cpu_physical_memory_write(p, atag_board_buf, atag_board_len);
p += atag_board_len;
}
/* ATAG_END */
WRITE_WORD(p, 0);
WRITE_WORD(p, 0);
}
static void set_kernel_args_old(const struct arm_boot_info *info)
{
hwaddr p;
const char *s;
int initrd_size = info->initrd_size;
hwaddr base = info->loader_start;
/* see linux/include/asm-arm/setup.h */
p = base + KERNEL_ARGS_ADDR;
/* page_size */
WRITE_WORD(p, 4096);
/* nr_pages */
WRITE_WORD(p, info->ram_size / 4096);
/* ramdisk_size */
WRITE_WORD(p, 0);
#define FLAG_READONLY 1
#define FLAG_RDLOAD 4
#define FLAG_RDPROMPT 8
/* flags */
WRITE_WORD(p, FLAG_READONLY | FLAG_RDLOAD | FLAG_RDPROMPT);
/* rootdev */
WRITE_WORD(p, (31 << 8) | 0); /* /dev/mtdblock0 */
/* video_num_cols */
WRITE_WORD(p, 0);
/* video_num_rows */
WRITE_WORD(p, 0);
/* video_x */
WRITE_WORD(p, 0);
/* video_y */
WRITE_WORD(p, 0);
/* memc_control_reg */
WRITE_WORD(p, 0);
/* unsigned char sounddefault */
/* unsigned char adfsdrives */
/* unsigned char bytes_per_char_h */
/* unsigned char bytes_per_char_v */
WRITE_WORD(p, 0);
/* pages_in_bank[4] */
WRITE_WORD(p, 0);
WRITE_WORD(p, 0);
WRITE_WORD(p, 0);
WRITE_WORD(p, 0);
/* pages_in_vram */
WRITE_WORD(p, 0);
/* initrd_start */
if (initrd_size) {
WRITE_WORD(p, info->initrd_start);
} else {
WRITE_WORD(p, 0);
}
/* initrd_size */
WRITE_WORD(p, initrd_size);
/* rd_start */
WRITE_WORD(p, 0);
/* system_rev */
WRITE_WORD(p, 0);
/* system_serial_low */
WRITE_WORD(p, 0);
/* system_serial_high */
WRITE_WORD(p, 0);
/* mem_fclk_21285 */
WRITE_WORD(p, 0);
/* zero unused fields */
while (p < base + KERNEL_ARGS_ADDR + 256 + 1024) {
WRITE_WORD(p, 0);
}
s = info->kernel_cmdline;
if (s) {
cpu_physical_memory_write(p, (void *)s, strlen(s) + 1);
} else {
WRITE_WORD(p, 0);
}
}
static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo)
{
#ifdef CONFIG_FDT
uint32_t *mem_reg_property;
uint32_t mem_reg_propsize;
void *fdt = NULL;
char *filename;
int size, rc;
uint32_t acells, scells, hival;
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);
if (!filename) {
fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);
return -1;
}
fdt = load_device_tree(filename, &size);
if (!fdt) {
fprintf(stderr, "Couldn't open dtb file %s\n", filename);
g_free(filename);
return -1;
}
g_free(filename);
acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");
scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");
if (acells == 0 || scells == 0) {
fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
return -1;
}
mem_reg_propsize = acells + scells;
mem_reg_property = g_new0(uint32_t, mem_reg_propsize);
mem_reg_property[acells - 1] = cpu_to_be32(binfo->loader_start);
hival = cpu_to_be32(binfo->loader_start >> 32);
if (acells > 1) {
mem_reg_property[acells - 2] = hival;
} else if (hival != 0) {
fprintf(stderr, "qemu: dtb file not compatible with "
"RAM start address > 4GB\n");
exit(1);
}
mem_reg_property[acells + scells - 1] = cpu_to_be32(binfo->ram_size);
hival = cpu_to_be32(binfo->ram_size >> 32);
if (scells > 1) {
mem_reg_property[acells + scells - 2] = hival;
} else if (hival != 0) {
fprintf(stderr, "qemu: dtb file not compatible with "
"RAM size > 4GB\n");
exit(1);
}
rc = qemu_devtree_setprop(fdt, "/memory", "reg", mem_reg_property,
mem_reg_propsize * sizeof(uint32_t));
if (rc < 0) {
fprintf(stderr, "couldn't set /memory/reg\n");
}
if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {
rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",
binfo->kernel_cmdline);
if (rc < 0) {
fprintf(stderr, "couldn't set /chosen/bootargs\n");
}
}
if (binfo->initrd_size) {
rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",
binfo->initrd_start);
if (rc < 0) {
fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
}
rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",
binfo->initrd_start + binfo->initrd_size);
if (rc < 0) {
fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
}
}
cpu_physical_memory_write(addr, fdt, size);
return 0;
#else
fprintf(stderr, "Device tree requested, "
"but qemu was compiled without fdt support\n");
return -1;
#endif
}
static void do_cpu_reset(void *opaque)
{
ARMCPU *cpu = opaque;
CPUARMState *env = &cpu->env;
const struct arm_boot_info *info = env->boot_info;
cpu_reset(CPU(cpu));
if (info) {
if (!info->is_linux) {
/* Jump to the entry point. */
env->regs[15] = info->entry & 0xfffffffe;
env->thumb = info->entry & 1;
} else {
if (env == first_cpu) {
env->regs[15] = info->loader_start;
if (!info->dtb_filename) {
if (old_param) {
set_kernel_args_old(info);
} else {
set_kernel_args(info);
}
}
} else {
info->secondary_cpu_reset_hook(cpu, info);
}
}
}
}
void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
{
CPUARMState *env = &cpu->env;
int kernel_size;
int initrd_size;
int n;
int is_linux = 0;
uint64_t elf_entry;
hwaddr entry;
int big_endian;
QemuOpts *machine_opts;
/* Load the kernel. */
if (!info->kernel_filename) {
fprintf(stderr, "Kernel image must be specified\n");
exit(1);
}
machine_opts = qemu_opts_find(qemu_find_opts("machine"), 0);
if (machine_opts) {
info->dtb_filename = qemu_opt_get(machine_opts, "dtb");
} else {
info->dtb_filename = NULL;
}
if (!info->secondary_cpu_reset_hook) {
info->secondary_cpu_reset_hook = default_reset_secondary;
}
if (!info->write_secondary_boot) {
info->write_secondary_boot = default_write_secondary;
}
if (info->nb_cpus == 0)
info->nb_cpus = 1;
#ifdef TARGET_WORDS_BIGENDIAN
big_endian = 1;
#else
big_endian = 0;
#endif
/* We want to put the initrd far enough into RAM that when the
* kernel is uncompressed it will not clobber the initrd. However
* on boards without much RAM we must ensure that we still leave
* enough room for a decent sized initrd, and on boards with large
* amounts of RAM we must avoid the initrd being so far up in RAM
* that it is outside lowmem and inaccessible to the kernel.
* So for boards with less than 256MB of RAM we put the initrd
* halfway into RAM, and for boards with 256MB of RAM or more we put
* the initrd at 128MB.
*/
info->initrd_start = info->loader_start +
MIN(info->ram_size / 2, 128 * 1024 * 1024);
/* Assume that raw images are linux kernels, and ELF images are not. */
kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,
NULL, NULL, big_endian, ELF_MACHINE, 1);
entry = elf_entry;
if (kernel_size < 0) {
kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
&is_linux);
}
if (kernel_size < 0) {
entry = info->loader_start + KERNEL_LOAD_ADDR;
kernel_size = load_image_targphys(info->kernel_filename, entry,
info->ram_size - KERNEL_LOAD_ADDR);
is_linux = 1;
}
if (kernel_size < 0) {
fprintf(stderr, "qemu: could not load kernel '%s'\n",
info->kernel_filename);
exit(1);
}
info->entry = entry;
if (is_linux) {
if (info->initrd_filename) {
initrd_size = load_image_targphys(info->initrd_filename,
info->initrd_start,
info->ram_size -
info->initrd_start);
if (initrd_size < 0) {
fprintf(stderr, "qemu: could not load initrd '%s'\n",
info->initrd_filename);
exit(1);
}
} else {
initrd_size = 0;
}
info->initrd_size = initrd_size;
bootloader[4] = info->board_id;
/* for device tree boot, we pass the DTB directly in r2. Otherwise
* we point to the kernel args.
*/
if (info->dtb_filename) {
/* Place the DTB after the initrd in memory */
hwaddr dtb_start = TARGET_PAGE_ALIGN(info->initrd_start +
initrd_size);
if (load_dtb(dtb_start, info)) {
exit(1);
}
bootloader[5] = dtb_start;
} else {
bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;
if (info->ram_size >= (1ULL << 32)) {
fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"
" Linux kernel using ATAGS (try passing a device tree"
" using -dtb)\n");
exit(1);
}
}
bootloader[6] = entry;
for (n = 0; n < sizeof(bootloader) / 4; n++) {
bootloader[n] = tswap32(bootloader[n]);
}
rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),
info->loader_start);
if (info->nb_cpus > 1) {
info->write_secondary_boot(cpu, info);
}
}
info->is_linux = is_linux;
for (; env; env = env->next_cpu) {
cpu = arm_env_get_cpu(env);
env->boot_info = info;
qemu_register_reset(do_cpu_reset, cpu);
}
}