mirror of
https://github.com/Telecominfraproject/OpenCellular.git
synced 2026-01-09 00:51:29 +00:00
ebdad6b0f2
There are no boards left that use this family of STM32 parts. If we add one later we can resurect support. Signed-off-by: Anton Staaf <robotboy@chromium.org> BRANCH=None BUG=None TEST=make buildall -j Change-Id: If985a9e9f93c935e98c93f33c075ce00cb9a91ac Reviewed-on: https://chromium-review.googlesource.com/282532 Tested-by: Anton Staaf <robotboy@chromium.org> Reviewed-by: Randall Spangler <rspangler@chromium.org> Commit-Queue: Anton Staaf <robotboy@chromium.org> Trybot-Ready: Anton Staaf <robotboy@chromium.org>
131 lines
3.2 KiB
C
131 lines
3.2 KiB
C
/* Copyright 2014 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.
|
|
*/
|
|
|
|
/* Flash memory module for Chrome EC */
|
|
|
|
#include "common.h"
|
|
#include "flash.h"
|
|
#include "hooks.h"
|
|
#include "registers.h"
|
|
#include "system.h"
|
|
#include "panic.h"
|
|
|
|
/* Flag indicating whether we have locked down entire flash */
|
|
static int entire_flash_locked;
|
|
|
|
#define FLASH_SYSJUMP_TAG 0x5750 /* "WP" - Write Protect */
|
|
#define FLASH_HOOK_VERSION 1
|
|
/* The previous write protect state before sys jump */
|
|
/*
|
|
* TODO(crosbug.com/p/23798): check if STM32L code works here too - that is,
|
|
* check if entire flash is locked by attempting to lock it rather than keeping
|
|
* a global variable.
|
|
*/
|
|
struct flash_wp_state {
|
|
int entire_flash_locked;
|
|
};
|
|
|
|
/*****************************************************************************/
|
|
/* Physical layer APIs */
|
|
|
|
int flash_physical_get_protect(int block)
|
|
{
|
|
return entire_flash_locked || !(STM32_FLASH_WRPR & (1 << block));
|
|
}
|
|
|
|
uint32_t flash_physical_get_protect_flags(void)
|
|
{
|
|
uint32_t flags = 0;
|
|
|
|
/* Read all-protected state from our shadow copy */
|
|
if (entire_flash_locked)
|
|
flags |= EC_FLASH_PROTECT_ALL_NOW;
|
|
|
|
return flags;
|
|
}
|
|
|
|
int flash_physical_protect_now(int all)
|
|
{
|
|
if (all) {
|
|
/*
|
|
* Lock by writing a wrong key to FLASH_KEYR. This triggers a
|
|
* bus fault, so we need to disable bus fault handler while
|
|
* doing this.
|
|
*/
|
|
ignore_bus_fault(1);
|
|
STM32_FLASH_KEYR = 0xffffffff;
|
|
ignore_bus_fault(0);
|
|
|
|
entire_flash_locked = 1;
|
|
|
|
return EC_SUCCESS;
|
|
} else {
|
|
/* No way to protect just the RO flash until next boot */
|
|
return EC_ERROR_INVAL;
|
|
}
|
|
}
|
|
|
|
uint32_t flash_physical_get_valid_flags(void)
|
|
{
|
|
return EC_FLASH_PROTECT_RO_AT_BOOT |
|
|
EC_FLASH_PROTECT_RO_NOW |
|
|
EC_FLASH_PROTECT_ALL_NOW;
|
|
}
|
|
|
|
uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
|
|
{
|
|
uint32_t ret = 0;
|
|
|
|
/* If RO protection isn't enabled, its at-boot state can be changed. */
|
|
if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
|
|
ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
|
|
|
|
/*
|
|
* If entire flash isn't protected at this boot, it can be enabled if
|
|
* the WP GPIO is asserted.
|
|
*/
|
|
if (!(cur_flags & EC_FLASH_PROTECT_ALL_NOW) &&
|
|
(cur_flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
|
|
ret |= EC_FLASH_PROTECT_ALL_NOW;
|
|
|
|
return ret;
|
|
}
|
|
|
|
int flash_physical_restore_state(void)
|
|
{
|
|
uint32_t reset_flags = system_get_reset_flags();
|
|
int version, size;
|
|
const struct flash_wp_state *prev;
|
|
|
|
/*
|
|
* If we have already jumped between images, an earlier image could
|
|
* have applied write protection. Nothing additional needs to be done.
|
|
*/
|
|
if (reset_flags & RESET_FLAG_SYSJUMP) {
|
|
prev = (const struct flash_wp_state *)system_get_jump_tag(
|
|
FLASH_SYSJUMP_TAG, &version, &size);
|
|
if (prev && version == FLASH_HOOK_VERSION &&
|
|
size == sizeof(*prev))
|
|
entire_flash_locked = prev->entire_flash_locked;
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*****************************************************************************/
|
|
/* Hooks */
|
|
|
|
static void flash_preserve_state(void)
|
|
{
|
|
struct flash_wp_state state;
|
|
|
|
state.entire_flash_locked = entire_flash_locked;
|
|
|
|
system_add_jump_tag(FLASH_SYSJUMP_TAG, FLASH_HOOK_VERSION,
|
|
sizeof(state), &state);
|
|
}
|
|
DECLARE_HOOK(HOOK_SYSJUMP, flash_preserve_state, HOOK_PRIO_DEFAULT);
|