qemu-patch-raspberry4/hw/moxie/moxiesim.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

159 lines
5.3 KiB
C

/*
* QEMU/moxiesim emulation
*
* Emulates a very simple machine model similar to the one used by the
* GDB moxie simulator.
*
* Copyright (c) 2008, 2009, 2010, 2013 Anthony Green
*
* 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/sysbus.h"
#include "hw/hw.h"
#include "hw/i386/pc.h"
#include "hw/isa/isa.h"
#include "net/net.h"
#include "sysemu/sysemu.h"
#include "hw/boards.h"
#include "hw/loader.h"
#include "hw/char/serial.h"
#include "exec/address-spaces.h"
#include "elf.h"
#define PHYS_MEM_BASE 0x80000000
typedef struct {
uint64_t ram_size;
const char *kernel_filename;
const char *kernel_cmdline;
const char *initrd_filename;
} LoaderParams;
static void load_kernel(MoxieCPU *cpu, LoaderParams *loader_params)
{
uint64_t entry, kernel_low, kernel_high;
long kernel_size;
long initrd_size;
ram_addr_t initrd_offset;
kernel_size = load_elf(loader_params->kernel_filename, NULL, NULL,
&entry, &kernel_low, &kernel_high, 1, EM_MOXIE,
0, 0);
if (kernel_size <= 0) {
fprintf(stderr, "qemu: could not load kernel '%s'\n",
loader_params->kernel_filename);
exit(1);
}
/* load initrd */
initrd_size = 0;
initrd_offset = 0;
if (loader_params->initrd_filename) {
initrd_size = get_image_size(loader_params->initrd_filename);
if (initrd_size > 0) {
initrd_offset = (kernel_high + ~TARGET_PAGE_MASK)
& TARGET_PAGE_MASK;
if (initrd_offset + initrd_size > loader_params->ram_size) {
fprintf(stderr,
"qemu: memory too small for initial ram disk '%s'\n",
loader_params->initrd_filename);
exit(1);
}
initrd_size = load_image_targphys(loader_params->initrd_filename,
initrd_offset,
ram_size);
}
if (initrd_size == (target_ulong)-1) {
fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
loader_params->initrd_filename);
exit(1);
}
}
}
static void main_cpu_reset(void *opaque)
{
MoxieCPU *cpu = opaque;
cpu_reset(CPU(cpu));
}
static void moxiesim_init(MachineState *machine)
{
MoxieCPU *cpu = NULL;
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;
CPUMoxieState *env;
MemoryRegion *address_space_mem = get_system_memory();
MemoryRegion *ram = g_new(MemoryRegion, 1);
MemoryRegion *rom = g_new(MemoryRegion, 1);
hwaddr ram_base = 0x200000;
LoaderParams loader_params;
/* Init CPUs. */
if (cpu_model == NULL) {
cpu_model = "MoxieLite-moxie-cpu";
}
cpu = cpu_moxie_init(cpu_model);
if (!cpu) {
fprintf(stderr, "Unable to find CPU definition\n");
exit(1);
}
env = &cpu->env;
qemu_register_reset(main_cpu_reset, cpu);
/* Allocate RAM. */
memory_region_init_ram(ram, NULL, "moxiesim.ram", ram_size, &error_fatal);
vmstate_register_ram_global(ram);
memory_region_add_subregion(address_space_mem, ram_base, ram);
memory_region_init_ram(rom, NULL, "moxie.rom", 128*0x1000, &error_fatal);
vmstate_register_ram_global(rom);
memory_region_add_subregion(get_system_memory(), 0x1000, rom);
if (kernel_filename) {
loader_params.ram_size = ram_size;
loader_params.kernel_filename = kernel_filename;
loader_params.kernel_cmdline = kernel_cmdline;
loader_params.initrd_filename = initrd_filename;
load_kernel(cpu, &loader_params);
}
/* A single 16450 sits at offset 0x3f8. */
if (serial_hds[0]) {
serial_mm_init(address_space_mem, 0x3f8, 0, env->irq[4],
8000000/16, serial_hds[0], DEVICE_LITTLE_ENDIAN);
}
}
static void moxiesim_machine_init(MachineClass *mc)
{
mc->desc = "Moxie simulator platform";
mc->init = moxiesim_init;
mc->is_default = 1;
}
DEFINE_MACHINE("moxiesim", moxiesim_machine_init)