| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2012 IBM Corporation |
| 3 | * |
| 4 | * Author: Ashley Lai <ashleydlai@gmail.com> |
| 5 | * Nayna Jain <nayna@linux.vnet.ibm.com> |
| 6 | * |
| 7 | * Maintained by: <tpmdd-devel@lists.sourceforge.net> |
| 8 | * |
| 9 | * Read the event log created by the firmware on PPC64 |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License |
| 13 | * as published by the Free Software Foundation; either version |
| 14 | * 2 of the License, or (at your option) any later version. |
| 15 | * |
| 16 | */ |
| 17 | |
| 18 | #include <linux/slab.h> |
| 19 | #include <linux/of.h> |
| 20 | #include <linux/tpm_eventlog.h> |
| 21 | |
| 22 | #include "../tpm.h" |
| 23 | #include "common.h" |
| 24 | |
| 25 | int tpm_read_log_of(struct tpm_chip *chip) |
| 26 | { |
| 27 | struct device_node *np; |
| 28 | const u32 *sizep; |
| 29 | const u64 *basep; |
| 30 | struct tpm_bios_log *log; |
| 31 | u32 size; |
| 32 | u64 base; |
| 33 | |
| 34 | log = &chip->log; |
| 35 | if (chip->dev.parent && chip->dev.parent->of_node) |
| 36 | np = chip->dev.parent->of_node; |
| 37 | else |
| 38 | return -ENODEV; |
| 39 | |
| 40 | if (of_property_read_bool(np, "powered-while-suspended")) |
| 41 | chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; |
| 42 | |
| 43 | sizep = of_get_property(np, "linux,sml-size", NULL); |
| 44 | basep = of_get_property(np, "linux,sml-base", NULL); |
| 45 | if (sizep == NULL && basep == NULL) |
| 46 | return -ENODEV; |
| 47 | if (sizep == NULL || basep == NULL) |
| 48 | return -EIO; |
| 49 | |
| 50 | /* |
| 51 | * For both vtpm/tpm, firmware has log addr and log size in big |
| 52 | * endian format. But in case of vtpm, there is a method called |
| 53 | * sml-handover which is run during kernel init even before |
| 54 | * device tree is setup. This sml-handover function takes care |
| 55 | * of endianness and writes to sml-base and sml-size in little |
| 56 | * endian format. For this reason, vtpm doesn't need conversion |
| 57 | * but physical tpm needs the conversion. |
| 58 | */ |
| 59 | if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0) { |
| 60 | size = be32_to_cpup((__force __be32 *)sizep); |
| 61 | base = be64_to_cpup((__force __be64 *)basep); |
| 62 | } else { |
| 63 | size = *sizep; |
| 64 | base = *basep; |
| 65 | } |
| 66 | |
| 67 | if (size == 0) { |
| 68 | dev_warn(&chip->dev, "%s: Event log area empty\n", __func__); |
| 69 | return -EIO; |
| 70 | } |
| 71 | |
| 72 | log->bios_event_log = kmemdup(__va(base), size, GFP_KERNEL); |
| 73 | if (!log->bios_event_log) |
| 74 | return -ENOMEM; |
| 75 | |
| 76 | log->bios_event_log_end = log->bios_event_log + size; |
| 77 | |
| 78 | if (chip->flags & TPM_CHIP_FLAG_TPM2) |
| 79 | return EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; |
| 80 | return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; |
| 81 | } |