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 device_node *node; 28 struct resource res; 29 int rc; 30 31 node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0); 32 if (!node) 33 return -ENODEV; 34 35 rc = of_address_to_resource(node, 0, &res); 36 of_node_put(node); 37 if (rc) 38 return rc; 39 40 chip->log.bios_event_log = devm_memremap(&chip->dev, res.start, resource_size(&res), 41 MEMREMAP_WB); 42 if (IS_ERR(chip->log.bios_event_log)) 43 return -ENOMEM; 44 45 chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res); 46 47 return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 : 48 EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; 49 } 50 51 int tpm_read_log_of(struct tpm_chip *chip) 52 { 53 struct device_node *np; 54 const u32 *sizep; 55 const u64 *basep; 56 struct tpm_bios_log *log; 57 u32 size; 58 u64 base; 59 60 log = &chip->log; 61 if (chip->dev.parent && chip->dev.parent->of_node) 62 np = chip->dev.parent->of_node; 63 else 64 return -ENODEV; 65 66 if (of_property_read_bool(np, "powered-while-suspended")) 67 chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; 68 69 sizep = of_get_property(np, "linux,sml-size", NULL); 70 basep = of_get_property(np, "linux,sml-base", NULL); 71 if (sizep == NULL && basep == NULL) 72 return tpm_read_log_memory_region(chip); 73 if (sizep == NULL || basep == NULL) 74 return -EIO; 75 76 /* 77 * For both vtpm/tpm, firmware has log addr and log size in big 78 * endian format. But in case of vtpm, there is a method called 79 * sml-handover which is run during kernel init even before 80 * device tree is setup. This sml-handover function takes care 81 * of endianness and writes to sml-base and sml-size in little 82 * endian format. For this reason, vtpm doesn't need conversion 83 * but physical tpm needs the conversion. 84 */ 85 if (of_property_match_string(np, "compatible", "IBM,vtpm") < 0 && 86 of_property_match_string(np, "compatible", "IBM,vtpm20") < 0) { 87 size = be32_to_cpup((__force __be32 *)sizep); 88 base = be64_to_cpup((__force __be64 *)basep); 89 } else { 90 size = *sizep; 91 base = *basep; 92 } 93 94 if (size == 0) { 95 dev_warn(&chip->dev, "%s: Event log area empty\n", __func__); 96 return -EIO; 97 } 98 99 log->bios_event_log = devm_kmemdup(&chip->dev, __va(base), size, GFP_KERNEL); 100 if (!log->bios_event_log) 101 return -ENOMEM; 102 103 log->bios_event_log_end = log->bios_event_log + size; 104 105 if (chip->flags & TPM_CHIP_FLAG_TPM2) 106 return EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; 107 return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; 108 } 109