From 6d448e3aa6c84487ec6d3fcc09cf015e4433619d Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Fri, 22 Jul 2016 08:28:57 -0700 Subject: google/chromeos: Add recovery module in vboot2 Add recovery module in vboot2 that checks if a recovery request is pending and returns appropriate reason code: 1. Checks if recovery mode is initiated by EC. 2. Checks if recovery request is present in VBNV. 3. Checks if recovery request is present in handoff for post-cbmem stages. 4. Checks if vboot verification is complete and looks up selected region to identify if recovery is requested by vboot library. BUG=chrome-os-partner:55431 Change-Id: I31e332a4d014a185df2434c3730954e08dc27281 Signed-off-by: Furquan Shaikh Reviewed-on: https://review.coreboot.org/15800 Reviewed-by: Aaron Durbin Tested-by: build bot (Jenkins) --- src/vendorcode/google/chromeos/vboot2/Makefile.inc | 6 ++ src/vendorcode/google/chromeos/vboot2/recovery.c | 120 +++++++++++++++++++++ src/vendorcode/google/chromeos/vboot_common.h | 6 ++ 3 files changed, 132 insertions(+) create mode 100644 src/vendorcode/google/chromeos/vboot2/recovery.c (limited to 'src/vendorcode/google/chromeos') diff --git a/src/vendorcode/google/chromeos/vboot2/Makefile.inc b/src/vendorcode/google/chromeos/vboot2/Makefile.inc index b0a3c125ab..31889e25a6 100644 --- a/src/vendorcode/google/chromeos/vboot2/Makefile.inc +++ b/src/vendorcode/google/chromeos/vboot2/Makefile.inc @@ -28,6 +28,12 @@ romstage-y += ../vboot_common.c ramstage-y += ../vboot_common.c postcar-y += ../vboot_common.c +bootblock-y += recovery.c +romstage-y += recovery.c +ramstage-y += recovery.c +verstage-y += recovery.c +postcar-y += recovery.c + bootblock-y += common.c libverstage-y += vboot_logic.c verstage-y += common.c diff --git a/src/vendorcode/google/chromeos/vboot2/recovery.c b/src/vendorcode/google/chromeos/vboot2/recovery.c new file mode 100644 index 0000000000..2cd5e806ea --- /dev/null +++ b/src/vendorcode/google/chromeos/vboot2/recovery.c @@ -0,0 +1,120 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2016 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include + +#include "misc.h" +#include "../vboot_common.h" + +static int vb2_get_recovery_reason_shared_data(void) +{ + /* Shared data does not exist for Ramstage and Post-CAR stage. */ + if (ENV_RAMSTAGE || ENV_POSTCAR) + return 0; + + struct vb2_shared_data *sd = vb2_get_shared_data(); + assert(sd); + return sd->recovery_reason; +} + +/* + * Returns 0 for the stages where we know that cbmem does not come online. + * Even if this function returns 1 for romstage, depending upon the point in + * bootup, cbmem might not actually be online. + */ +static int cbmem_possibly_online(void) +{ + if (ENV_BOOTBLOCK) + return 0; + + if (ENV_VERSTAGE && IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) + return 0; + + return 1; +} + +/* + * Returns 1 if vboot is being used and currently in a stage which might have + * already executed vboot verification. + */ +static int vboot_possibly_executed(void) +{ + if (!IS_ENABLED(CONFIG_VBOOT_VERIFY_FIRMWARE)) + return 0; + + if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_BOOTBLOCK)) { + if (ENV_BOOTBLOCK && IS_ENABLED(CONFIG_SEPARATE_VERSTAGE)) + return 0; + return 1; + } + + if (IS_ENABLED(CONFIG_VBOOT_STARTS_IN_ROMSTAGE)) { + if (ENV_BOOTBLOCK) + return 0; + return 1; + } + + return 0; +} + +/* + * vb2_check_recovery_request looks up different components to identify if there + * is a recovery request and returns appropriate reason code: + * 1. Checks if recovery mode is initiated by EC. If yes, returns + * VB2_RECOVERY_RO_MANUAL. + * 2. Checks if recovery request is present in VBNV and returns the code read + * from it. + * 3. Checks recovery request in handoff for stages post-cbmem. + * 4. For non-CBMEM stages, check if vboot verification is done and look-up + * selected region to identify if vboot_refence library has requested recovery + * path. If yes, return the reason code from shared data. + * 5. If nothing applies, return 0 indicating no recovery request. + */ +int vboot_check_recovery_request(void) +{ + int reason = 0; + + /* EC-initiated recovery. */ + if (get_recovery_mode_switch()) + return VB2_RECOVERY_RO_MANUAL; + + /* Recovery request in VBNV. */ + if ((reason = get_recovery_mode_from_vbnv()) != 0) + return reason; + + /* + * Check recovery flag in vboot_handoff for stages post CBMEM coming + * online. Since for some stages there is no way to know if cbmem has + * already come online, try looking up handoff anyways. If it fails, + * flow will fallback to looking up shared data. + */ + if (cbmem_possibly_online() && + ((reason = vboot_handoff_get_recovery_reason()) != 0)) + return reason; + + /* + * For stages where CBMEM might not be online, identify if vboot + * verification is already complete and no slot was selected + * i.e. recovery path was requested. + */ + if (vboot_possibly_executed() && vb2_logic_executed() && + !vb2_is_slot_selected()) + return vb2_get_recovery_reason_shared_data(); + + return 0; +} diff --git a/src/vendorcode/google/chromeos/vboot_common.h b/src/vendorcode/google/chromeos/vboot_common.h index ae135fe66f..266ce4f6b3 100644 --- a/src/vendorcode/google/chromeos/vboot_common.h +++ b/src/vendorcode/google/chromeos/vboot_common.h @@ -25,6 +25,12 @@ /* Locate vboot area by name. Returns 0 on success and -1 on error. */ int vboot_named_region_device(const char *name, struct region_device *rdev); +/* + * Function to check if there is a request to enter recovery mode. Returns + * reason code if request to enter recovery mode is present, otherwise 0. + */ +int vboot_check_recovery_request(void); + /* ========================== VBOOT HANDOFF APIs =========================== */ /* * The vboot_handoff structure contains the data to be consumed by downstream -- cgit v1.2.3