qemu/hw/m68k/an5206.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

102 lines
2.8 KiB
C

/*
* Arnewsh 5206 ColdFire system emulation.
*
* Copyright (c) 2007 CodeSourcery.
*
* This code is licensed under the GPL
*/
#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/m68k/mcf.h"
#include "hw/boards.h"
#include "hw/loader.h"
#include "elf.h"
#include "exec/address-spaces.h"
#include "qemu/error-report.h"
#include "sysemu/qtest.h"
#define KERNEL_LOAD_ADDR 0x10000
#define AN5206_MBAR_ADDR 0x10000000
#define AN5206_RAMBAR_ADDR 0x20000000
/* Board init. */
static void an5206_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;
M68kCPU *cpu;
CPUM68KState *env;
int kernel_size;
uint64_t elf_entry;
hwaddr entry;
MemoryRegion *address_space_mem = get_system_memory();
MemoryRegion *ram = g_new(MemoryRegion, 1);
MemoryRegion *sram = g_new(MemoryRegion, 1);
if (!cpu_model) {
cpu_model = "m5206";
}
cpu = cpu_m68k_init(cpu_model);
if (!cpu) {
error_report("Unable to find m68k CPU definition");
exit(1);
}
env = &cpu->env;
/* Initialize CPU registers. */
env->vbr = 0;
/* TODO: allow changing MBAR and RAMBAR. */
env->mbar = AN5206_MBAR_ADDR | 1;
env->rambar0 = AN5206_RAMBAR_ADDR | 1;
/* DRAM at address zero */
memory_region_allocate_system_memory(ram, NULL, "an5206.ram", ram_size);
memory_region_add_subregion(address_space_mem, 0, ram);
/* Internal SRAM. */
memory_region_init_ram(sram, NULL, "an5206.sram", 512, &error_fatal);
vmstate_register_ram_global(sram);
memory_region_add_subregion(address_space_mem, AN5206_RAMBAR_ADDR, sram);
mcf5206_init(address_space_mem, AN5206_MBAR_ADDR, cpu);
/* Load kernel. */
if (!kernel_filename) {
if (qtest_enabled()) {
return;
}
fprintf(stderr, "Kernel image must be specified\n");
exit(1);
}
kernel_size = load_elf(kernel_filename, NULL, NULL, &elf_entry,
NULL, NULL, 1, EM_68K, 0, 0);
entry = elf_entry;
if (kernel_size < 0) {
kernel_size = load_uimage(kernel_filename, &entry, NULL, NULL,
NULL, NULL);
}
if (kernel_size < 0) {
kernel_size = load_image_targphys(kernel_filename, KERNEL_LOAD_ADDR,
ram_size - KERNEL_LOAD_ADDR);
entry = KERNEL_LOAD_ADDR;
}
if (kernel_size < 0) {
fprintf(stderr, "qemu: could not load kernel '%s'\n", kernel_filename);
exit(1);
}
env->pc = entry;
}
static void an5206_machine_init(MachineClass *mc)
{
mc->desc = "Arnewsh 5206";
mc->init = an5206_init;
}
DEFINE_MACHINE("an5206", an5206_machine_init)