historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/roms/skiboot/external/memboot/memboot.c
2024-01-16 11:20:27 -06:00

150 lines
3.6 KiB
C

/* Copyright 2013-2014 IBM Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/mman.h>
/* Where to put the firmware image if booting from memory */
#define MEM_IMG_BASE (0x5c000000)
/* Start of flash memory if booting from flash */
#define FLASH_IMG_BASE (0x30000000)
/* LPC registers */
#define LPC_BASE 0x1e789000
#define LPC_HICR6 0x80
#define LPC_HICR7 0x88
#define LPC_HICR8 0x8c
#define LPC_SCR0SIO 0x170
#define MEMBOOT_SIO_VERSION_FLAG 0x42
#define MEMBOOT_SIO_FLAG (0x10 << 8)
uint32_t readl(void *addr)
{
asm volatile("" : : : "memory");
return *(volatile uint32_t *)addr;
}
void writel(uint32_t val, void *addr)
{
asm volatile("" : : : "memory");
*(volatile uint32_t *)addr = val;
}
void copy_flash_img(int mem_fd, int flash_fd, unsigned int size)
{
static void *memimg, *fwimg;
size_t pagesize = getpagesize();
memimg = mmap(NULL, ((size/pagesize)+1)*pagesize,
PROT_READ | PROT_WRITE, MAP_SHARED, mem_fd, MEM_IMG_BASE);
if (memimg == MAP_FAILED) {
perror("Unable to map image destination memory");
exit(1);
}
fwimg = mmap(NULL,size, PROT_READ, MAP_SHARED, flash_fd, 0);
if (fwimg == MAP_FAILED) {
perror("Unable to open image source memory");
exit(1);
}
/* Copy boot image */
memcpy(memimg, fwimg, size);
}
void boot_firmware_image(int mem_fd, char *filename)
{
int fw_fd;
struct stat st;
fw_fd = open(filename, O_RDONLY);
if (fw_fd < 0) {
perror("Unable to open flash image\n");
exit(1);
}
if (stat(filename, &st)) {
perror("Unable to determine size of firmware image");
exit(1);
}
if (st.st_size > 32*1024*1024) {
fprintf(stderr, "Flash too large (> 32MB)");
exit(1);
}
copy_flash_img(mem_fd, fw_fd, st.st_size);
close(fw_fd);
}
int main(int argc, char *argv[])
{
int mem_fd;
void *lpcreg;
uint32_t lpc_scr0sio_val;
uint32_t lpc_hicr7_val = (FLASH_IMG_BASE | 0xe00);
if (argc > 2) {
printf("Usage: %s <flash image>\n", argv[0]);
exit(1);
}
mem_fd = open("/dev/mem", O_RDWR | O_SYNC);
if (mem_fd < 0) {
perror("Unable to open /dev/mem");
exit(1);
}
lpcreg = mmap(NULL, getpagesize(),
PROT_READ | PROT_WRITE, MAP_SHARED, mem_fd, LPC_BASE);
if (lpcreg == MAP_FAILED) {
perror("Unable to map LPC register memory");
exit(1);
}
lpc_scr0sio_val = readl(lpcreg+LPC_SCR0SIO);
lpc_scr0sio_val &= ~0xff;
lpc_scr0sio_val |= MEMBOOT_SIO_VERSION_FLAG;
lpc_scr0sio_val &= ~MEMBOOT_SIO_FLAG;
if (argc == 2) {
boot_firmware_image(mem_fd, argv[1]);
lpc_hicr7_val = (MEM_IMG_BASE | 0xe00);
/* Set the boot mode scratch register to indicate a memboot */
lpc_scr0sio_val |= MEMBOOT_SIO_FLAG;
printf("Booting from memory after power cycle\n");
}
if (readl(lpcreg + LPC_HICR7) != lpc_hicr7_val) {
printf("Resetting LPC_HICR7 to 0x%x\n", lpc_hicr7_val);
writel(lpc_hicr7_val, lpcreg+LPC_HICR7);
}
/* Set the magic value */
writel(0x42, lpcreg+LPC_SCR0SIO);
writel(lpc_scr0sio_val, lpcreg+LPC_SCR0SIO);
printf("LPC_HICR7 = 0x%x\n", lpc_hicr7_val);
return 0;
}