1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright 2012 IBM Corporation 4 * 5 * Author: Ashley Lai <ashleydlai@gmail.com> 6 * Nayna Jain <nayna@linux.vnet.ibm.com> 7 * 8 * Maintained by: <tpmdd-devel@lists.sourceforge.net> 9 * 10 * Read the event log created by the firmware on PPC64 11 */ 12 13 #include <linux/device.h> 14 #include <linux/slab.h> 15 #include <linux/io.h> 16 #include <linux/ioport.h> 17 #include <linux/of.h> 18 #include <linux/of_address.h> 19 #include <linux/of_reserved_mem.h> 20 #include <linux/tpm_eventlog.h> 21 22 #include "../tpm.h" 23 #include "common.h" 24 25 static int tpm_read_log_memory_region(struct tpm_chip *chip) 26 { 27 struct resource res; 28 int rc; 29 30 rc = of_reserved_mem_region_to_resource(chip->dev.parent->of_node, 0, &res); 31 if (rc) 32 return rc; 33 34 chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res), 35 MEMREMAP_WB); 36 if (IS_ERR(chip->log.bios_event_log)) 37 return -ENOMEM; 38 39 chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res); 40 41 return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 : 42 EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; 43 } 44 45 int tpm_read_log_of(struct tpm_chip *chip) 46 { 47 struct device_node *np; 48 const u32 *sizep; 49 const u64 *basep; 50 struct tpm_bios_log *log; 51 u32 size; 52 u64 base; 53 54 log = &chip->log; 55 if (chip->dev.parent && chip->dev.parent->of_node) 56 np = chip->dev.parent->of_node; 57 else 58 return -ENODEV; 59 60 if (of_property_read_bool(np, "powered-while-suspended")) 61 chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; 62 63 sizep = of_get_property(np, "linux,sml-size", NULL); 64 basep = of_get_property(np, "linux,sml-base", NULL); 65 if (sizep == NULL && basep == NULL) 66 return tpm_read_log_memory_region(chip); 67 if (sizep == NULL || basep == NULL) 68 return -EIO; 69 70 /* 71 * For both vtpm/tpm, firmware has log addr and log size in big 72 * endian format. But in case of vtpm, there is a method called 73 * sml-handover which is run during kernel init even before 74 * device tree is setup. This sml-handover function takes care 75 * of endianness and writes to sml-base and sml-size in little 76 * endian format. For this reason, vtpm doesn't need conversion 77 * but physical tpm needs the conversion. 78 */ 79 if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0 && 80 of_property_match_string(np, "compatible", "IBM,vtpm20") < 0) { 81 size = be32_to_cpup((__force __be32 *)sizep); 82 base = be64_to_cpup((__force __be64 *)basep); 83 } else { 84 size = *sizep; 85 base = *basep; 86 } 87 88 if (size == 0) { 89 dev_warn(&chip->dev, "%s: Event log area empty\n", __func__); 90 return -EIO; 91 } 92 93 log->bios_event_log = devm_kmemdup(&chip->dev, __va(base), size, GFP_KERNEL); 94 if (!log->bios_event_log) 95 return -ENOMEM; 96 97 log->bios_event_log_end = log->bios_event_log + size; 98 99 if (chip->flags & TPM_CHIP_FLAG_TPM2) 100 return EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; 101 return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; 102 } 103