qemu-patch-raspberry4/hw/mips/mips_mipssim.c
Peter Crosthwaite 7ef295ea5b loader: Add data swap option to load-elf
Some CPUs are of an opposite data-endianness to other components in the
system. Sometimes elfs have the data sections layed out with this CPU
data-endianness accounting for when loaded via the CPU, so byte swaps
(relative to other system components) will occur.

The leading example, is ARM's BE32 mode, which is is basically LE with
address manipulation on half-word and byte accesses to access the
hw/byte reversed address. This means that word data is invariant
across LE and BE32. This also means that instructions are still LE.
The expectation is that the elf will be loaded via the CPU in this
endianness scheme, which means the data in the elf is reversed at
compile time.

As QEMU loads via the system memory directly, rather than the CPU, we
need a mechanism to reverse elf data endianness to implement this
possibility.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-03-04 11:30:21 +00:00

242 lines
7.8 KiB
C

/*
* QEMU/mipssim emulation
*
* Emulates a very simple machine model similar to the one used by the
* proprietary MIPS emulator.
*
* Copyright (c) 2007 Thiemo Seufer
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/mips/mips.h"
#include "hw/mips/cpudevs.h"
#include "hw/char/serial.h"
#include "hw/isa/isa.h"
#include "net/net.h"
#include "sysemu/sysemu.h"
#include "hw/boards.h"
#include "hw/mips/bios.h"
#include "hw/loader.h"
#include "elf.h"
#include "hw/sysbus.h"
#include "exec/address-spaces.h"
#include "qemu/error-report.h"
#include "sysemu/qtest.h"
static struct _loaderparams {
int ram_size;
const char *kernel_filename;
const char *kernel_cmdline;
const char *initrd_filename;
} loaderparams;
typedef struct ResetData {
MIPSCPU *cpu;
uint64_t vector;
} ResetData;
static int64_t load_kernel(void)
{
int64_t entry, kernel_high;
long kernel_size;
long initrd_size;
ram_addr_t initrd_offset;
int big_endian;
#ifdef TARGET_WORDS_BIGENDIAN
big_endian = 1;
#else
big_endian = 0;
#endif
kernel_size = load_elf(loaderparams.kernel_filename, cpu_mips_kseg0_to_phys,
NULL, (uint64_t *)&entry, NULL,
(uint64_t *)&kernel_high, big_endian,
EM_MIPS, 1, 0);
if (kernel_size >= 0) {
if ((entry & ~0x7fffffffULL) == 0x80000000)
entry = (int32_t)entry;
} else {
fprintf(stderr, "qemu: could not load kernel '%s'\n",
loaderparams.kernel_filename);
exit(1);
}
/* load initrd */
initrd_size = 0;
initrd_offset = 0;
if (loaderparams.initrd_filename) {
initrd_size = get_image_size (loaderparams.initrd_filename);
if (initrd_size > 0) {
initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) & INITRD_PAGE_MASK;
if (initrd_offset + initrd_size > loaderparams.ram_size) {
fprintf(stderr,
"qemu: memory too small for initial ram disk '%s'\n",
loaderparams.initrd_filename);
exit(1);
}
initrd_size = load_image_targphys(loaderparams.initrd_filename,
initrd_offset, loaderparams.ram_size - initrd_offset);
}
if (initrd_size == (target_ulong) -1) {
fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
loaderparams.initrd_filename);
exit(1);
}
}
return entry;
}
static void main_cpu_reset(void *opaque)
{
ResetData *s = (ResetData *)opaque;
CPUMIPSState *env = &s->cpu->env;
cpu_reset(CPU(s->cpu));
env->active_tc.PC = s->vector & ~(target_ulong)1;
if (s->vector & 1) {
env->hflags |= MIPS_HFLAG_M16;
}
}
static void mipsnet_init(int base, qemu_irq irq, NICInfo *nd)
{
DeviceState *dev;
SysBusDevice *s;
dev = qdev_create(NULL, "mipsnet");
qdev_set_nic_properties(dev, nd);
qdev_init_nofail(dev);
s = SYS_BUS_DEVICE(dev);
sysbus_connect_irq(s, 0, irq);
memory_region_add_subregion(get_system_io(),
base,
sysbus_mmio_get_region(s, 0));
}
static void
mips_mipssim_init(MachineState *machine)
{
ram_addr_t ram_size = machine->ram_size;
const char *cpu_model = machine->cpu_model;
const char *kernel_filename = machine->kernel_filename;
const char *kernel_cmdline = machine->kernel_cmdline;
const char *initrd_filename = machine->initrd_filename;
char *filename;
MemoryRegion *address_space_mem = get_system_memory();
MemoryRegion *isa = g_new(MemoryRegion, 1);
MemoryRegion *ram = g_new(MemoryRegion, 1);
MemoryRegion *bios = g_new(MemoryRegion, 1);
MIPSCPU *cpu;
CPUMIPSState *env;
ResetData *reset_info;
int bios_size;
/* Init CPUs. */
if (cpu_model == NULL) {
#ifdef TARGET_MIPS64
cpu_model = "5Kf";
#else
cpu_model = "24Kf";
#endif
}
cpu = cpu_mips_init(cpu_model);
if (cpu == NULL) {
fprintf(stderr, "Unable to find CPU definition\n");
exit(1);
}
env = &cpu->env;
reset_info = g_malloc0(sizeof(ResetData));
reset_info->cpu = cpu;
reset_info->vector = env->active_tc.PC;
qemu_register_reset(main_cpu_reset, reset_info);
/* Allocate RAM. */
memory_region_allocate_system_memory(ram, NULL, "mips_mipssim.ram",
ram_size);
memory_region_init_ram(bios, NULL, "mips_mipssim.bios", BIOS_SIZE,
&error_fatal);
vmstate_register_ram_global(bios);
memory_region_set_readonly(bios, true);
memory_region_add_subregion(address_space_mem, 0, ram);
/* Map the BIOS / boot exception handler. */
memory_region_add_subregion(address_space_mem, 0x1fc00000LL, bios);
/* Load a BIOS / boot exception handler image. */
if (bios_name == NULL)
bios_name = BIOS_FILENAME;
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (filename) {
bios_size = load_image_targphys(filename, 0x1fc00000LL, BIOS_SIZE);
g_free(filename);
} else {
bios_size = -1;
}
if ((bios_size < 0 || bios_size > BIOS_SIZE) &&
!kernel_filename && !qtest_enabled()) {
/* Bail out if we have neither a kernel image nor boot vector code. */
error_report("Could not load MIPS bios '%s', and no "
"-kernel argument was specified", bios_name);
exit(1);
} else {
/* We have a boot vector start address. */
env->active_tc.PC = (target_long)(int32_t)0xbfc00000;
}
if (kernel_filename) {
loaderparams.ram_size = ram_size;
loaderparams.kernel_filename = kernel_filename;
loaderparams.kernel_cmdline = kernel_cmdline;
loaderparams.initrd_filename = initrd_filename;
reset_info->vector = load_kernel();
}
/* Init CPU internal devices. */
cpu_mips_irq_init_cpu(env);
cpu_mips_clock_init(env);
/* Register 64 KB of ISA IO space at 0x1fd00000. */
memory_region_init_alias(isa, NULL, "isa_mmio",
get_system_io(), 0, 0x00010000);
memory_region_add_subregion(get_system_memory(), 0x1fd00000, isa);
/* A single 16450 sits at offset 0x3f8. It is attached to
MIPS CPU INT2, which is interrupt 4. */
if (serial_hds[0])
serial_init(0x3f8, env->irq[4], 115200, serial_hds[0],
get_system_io());
if (nd_table[0].used)
/* MIPSnet uses the MIPS CPU INT0, which is interrupt 2. */
mipsnet_init(0x4200, env->irq[2], &nd_table[0]);
}
static void mips_mipssim_machine_init(MachineClass *mc)
{
mc->desc = "MIPS MIPSsim platform";
mc->init = mips_mipssim_init;
}
DEFINE_MACHINE("mipssim", mips_mipssim_machine_init)