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/* Copyright 2015 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "common.h"
#include "debug_printf.h"
#include "printf.h"
#include "registers.h"
#include "setup.h"
#include "signed_header.h"
#include "system.h"
#include "trng.h"
#include "uart.h"
/*
* This file is a proof of concept stub which will be extended and split into
* appropriate pieces shortly, when full blown support for cr50 bootrom is
* introduced.
*/
uint32_t sleep_mask;
timestamp_t get_time(void)
{
timestamp_t ret;
ret.val = 0;
return ret;
}
static int panic_txchar(void *context, int c)
{
if (c == '\n')
panic_txchar(context, '\r');
/* Wait for space in transmit FIFO */
while (!uart_tx_ready())
;
/* Write the character directly to the transmit FIFO */
uart_write_char(c);
return 0;
}
void panic_puts(const char *outstr)
{
/* Put all characters in the output buffer */
while (*outstr)
panic_txchar(NULL, *outstr++);
}
void panic_printf(const char *format, ...)
{
va_list args;
va_start(args, format);
vfnprintf(panic_txchar, NULL, format, args);
va_end(args);
}
/* Returns 1 if version a is newer, 0 otherwise. */
int is_newer_than(const struct SignedHeader *a, const struct SignedHeader *b)
{
if (a->epoch_ != b->epoch_)
return a->epoch_ > b->epoch_;
if (a->major_ != b->major_)
return a->major_ > b->major_;
if (a->minor_ != b->minor_)
return a->minor_ > b->minor_;
if (a->timestamp_ != b->timestamp_)
return a->timestamp_ > b->timestamp_;
return 1; /* All else being equal, consider A to be newer. */
}
int main(void)
{
const struct SignedHeader *a, *b, *first, *second;
init_trng();
uart_init();
debug_printf("\n\n%s bootloader, %8u_%u@%u\n",
STRINGIFY(BOARD), GREG32(SWDP, BUILD_DATE),
GREG32(SWDP, BUILD_TIME), GREG32(SWDP, P4_LAST_SYNC));
unlockFlashForRW();
a = (const struct SignedHeader *)(CONFIG_PROGRAM_MEMORY_BASE +
CONFIG_RW_MEM_OFF);
b = (const struct SignedHeader *)(CONFIG_PROGRAM_MEMORY_BASE +
CONFIG_RW_B_MEM_OFF);
/* Default to loading the older version first.
* Run from bank a if the versions are equal.
*/
if (is_newer_than(a, b)) {
first = a;
second = b;
} else {
first = b;
second = a;
}
if (GREG32(PMU, PWRDN_SCRATCH30) == 0xcafebabe) {
/* Launch from the alternate bank first.
* This knob will be used to attempt to load the newer version
* after an update and to run from bank b in the face of flash
* integrity issues.
*/
debug_printf("PWRDN_SCRATCH30 set to magic value\n");
GREG32(PMU, PWRDN_SCRATCH30) = 0x0;
a = first;
first = second;
second = a;
}
tryLaunch((uint32_t)first, CONFIG_RW_SIZE);
debug_printf("Failed to launch.\n");
debug_printf("Attempting to load the alternate image.\n");
tryLaunch((uint32_t)second, CONFIG_RW_SIZE);
debug_printf("No valid image found, not sure what to do...\n");
/* TODO: Some applications might want to reboot instead. */
halt();
return 1;
}
void panic_reboot(void)
{
panic_puts("\n\nRebooting...\n");
system_reset(0);
}
void interrupt_disable(void)
{
asm("cpsid i");
}
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