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/* Copyright 2016 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 "console.h"
#include "hooks.h"
#include "registers.h"
#include "system.h"
#include "task.h"
#include "timer.h"
#define CPRINTS(format, args...) cprints(CC_RBOX, format, ## args)
#define CPRINTF(format, args...) cprintf(CC_RBOX, format, ## args)
static int command_wp(int argc, char **argv)
{
int val;
if (argc > 1) {
if (!parse_bool(argv[1], &val))
return EC_ERROR_PARAM1;
/* Invert, because active low */
GREG32(RBOX, EC_WP_L) = !val;
}
/* Invert, because active low */
val = !GREG32(RBOX, EC_WP_L);
ccprintf("Flash WP is %s\n", val ? "enabled" : "disabled");
return EC_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(wp, command_wp,
"[<BOOLEAN>]",
"Get/set the flash HW write-protect signal");
/* When the system is locked down, provide a means to unlock it */
#ifdef CONFIG_RESTRICTED_CONSOLE_COMMANDS
/* TODO(crosbug.com/p/55510): It should be locked by default */
static int console_restricted_state;
int console_is_restricted(void)
{
return console_restricted_state;
}
/****************************************************************************/
/* Stuff for the unlock sequence */
/* Total time to spend poking the power button */
#define UNLOCK_TIME (10 * SECOND)
/* Max time between pokes */
#define UNLOCK_BEAT (2 * SECOND)
static timestamp_t unlock_deadline;
static int unlock_in_progress;
/* Only invoked when the unlock sequence is done, either good or bad. */
static void unlock_sequence_is_over(void)
{
if (unlock_in_progress) {
CPRINTS("Unlock process failed");
} else {
CPRINTS("Unlock process completed successfully");
console_restricted_state = 0;
}
unlock_in_progress = 0;
/* Disable power button interrupt */
GWRITE_FIELD(RBOX, INT_ENABLE, INTR_PWRB_IN_FED, 0);
task_disable_irq(GC_IRQNUM_RBOX0_INTR_PWRB_IN_FED_INT);
/* Allow sleeping again */
enable_sleep(SLEEP_MASK_FORCE_NO_DSLEEP);
}
DECLARE_DEFERRED(unlock_sequence_is_over);
static void power_button_poked(void)
{
if (timestamp_expired(unlock_deadline, NULL)) {
/* We've been poking for long enough */
unlock_in_progress = 0;
hook_call_deferred(&unlock_sequence_is_over_data, 0);
CPRINTS("poke: enough already", __func__);
} else {
/* Wait for the next poke */
hook_call_deferred(&unlock_sequence_is_over_data, UNLOCK_BEAT);
CPRINTS("poke");
}
GWRITE_FIELD(RBOX, INT_STATE, INTR_PWRB_IN_FED, 1);
}
DECLARE_IRQ(GC_IRQNUM_RBOX0_INTR_PWRB_IN_FED_INT, power_button_poked, 1);
static int start_the_unlock_process(void)
{
/* Don't invoke more than one at a time */
if (unlock_in_progress)
return EC_ERROR_BUSY;
unlock_in_progress = 1;
/* Clear any leftover power button interrupts */
GWRITE_FIELD(RBOX, INT_STATE, INTR_PWRB_IN_FED, 1);
/* Enable power button interrupt */
GWRITE_FIELD(RBOX, INT_ENABLE, INTR_PWRB_IN_FED, 1);
task_enable_irq(GC_IRQNUM_RBOX0_INTR_PWRB_IN_FED_INT);
/* Keep poking until it's been long enough */
unlock_deadline = get_time();
unlock_deadline.val += UNLOCK_TIME;
/* Stay awake while we're doing this, just in case. */
disable_sleep(SLEEP_MASK_FORCE_NO_DSLEEP);
/* Check progress after waiting long enough for one button press */
hook_call_deferred(&unlock_sequence_is_over_data, UNLOCK_BEAT);
CPRINTS("Unlock sequence starting. Continue until %.6ld",
unlock_deadline);
return EC_SUCCESS;
}
/****************************************************************************/
static int command_lock(int argc, char **argv)
{
int enabled;
int i;
if (argc > 1) {
if (!parse_bool(argv[1], &enabled))
return EC_ERROR_PARAM1;
/* Changing nothing does nothing */
if (enabled == console_restricted_state)
goto out;
/* Locking the console is always allowed */
if (enabled) {
console_restricted_state = 1;
goto out;
}
/*
* TODO(crosbug.com/p/55322, crosbug.com/p/55728): There may be
* other preconditions which must be satisified before
* continuing. We can return EC_ERROR_ACCESS_DENIED if those
* aren't met.
*/
/* Don't count down if we know it's likely to fail */
if (unlock_in_progress) {
ccprintf("An unlock process is already in progress\n");
return EC_ERROR_BUSY;
}
/* Now the user has to sit there and poke the button */
ccprintf("Start poking the power button in ");
for (i = 5; i; i--) {
ccprintf("%d ", i);
sleep(1);
}
ccprintf("go!\n");
return start_the_unlock_process();
}
out:
ccprintf("The restricted console lock is %s\n",
console_is_restricted() ? "enabled" : "disabled");
return EC_SUCCESS;
}
DECLARE_SAFE_CONSOLE_COMMAND(lock, command_lock,
"[<BOOLEAN>]",
"Get/Set the restricted console lock");
#endif /* CONFIG_RESTRICTED_CONSOLE_COMMANDS */
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