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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2012-2014 Intel Corporation4 *5 * Authors:6 * Xiaoyan Zhang <xiaoyan.zhang@intel.com>7 * Jiang Liu <jiang.liu@linux.intel.com>8 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>9 *10 * Maintained by: <tpmdd-devel@lists.sourceforge.net>11 *12 * This file contains implementation of the sysfs interface for PPI.13 */14 15 16#include <linux/acpi.h>17#include "tpm.h"18 19#define TPM_PPI_REVISION_ID_1 120#define TPM_PPI_REVISION_ID_2 221#define TPM_PPI_FN_VERSION 122#define TPM_PPI_FN_SUBREQ 223#define TPM_PPI_FN_GETREQ 324#define TPM_PPI_FN_GETACT 425#define TPM_PPI_FN_GETRSP 526#define TPM_PPI_FN_SUBREQ2 727#define TPM_PPI_FN_GETOPR 828#define PPI_TPM_REQ_MAX 101 /* PPI 1.3 for TPM 2 */29#define PPI_VS_REQ_START 12830#define PPI_VS_REQ_END 25531 32static const guid_t tpm_ppi_guid =33 GUID_INIT(0x3DDDFAA6, 0x361B, 0x4EB4,34 0xA4, 0x24, 0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53);35 36static bool tpm_ppi_req_has_parameter(u64 req)37{38 return req == 23;39}40 41static inline union acpi_object *42tpm_eval_dsm(acpi_handle ppi_handle, int func, acpi_object_type type,43 union acpi_object *argv4, u64 rev)44{45 BUG_ON(!ppi_handle);46 return acpi_evaluate_dsm_typed(ppi_handle, &tpm_ppi_guid,47 rev, func, argv4, type);48}49 50static ssize_t tpm_show_ppi_version(struct device *dev,51 struct device_attribute *attr, char *buf)52{53 struct tpm_chip *chip = to_tpm_chip(dev);54 55 return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);56}57 58static ssize_t tpm_show_ppi_request(struct device *dev,59 struct device_attribute *attr, char *buf)60{61 ssize_t size = -EINVAL;62 union acpi_object *obj;63 struct tpm_chip *chip = to_tpm_chip(dev);64 u64 rev = TPM_PPI_REVISION_ID_2;65 u64 req;66 67 if (strcmp(chip->ppi_version, "1.2") < 0)68 rev = TPM_PPI_REVISION_ID_1;69 70 obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETREQ,71 ACPI_TYPE_PACKAGE, NULL, rev);72 if (!obj)73 return -ENXIO;74 75 /*76 * output.pointer should be of package type, including two integers.77 * The first is function return code, 0 means success and 1 means78 * error. The second is pending TPM operation requested by the OS, 079 * means none and >0 means operation value.80 */81 if (obj->package.count == 3 &&82 obj->package.elements[0].type == ACPI_TYPE_INTEGER &&83 obj->package.elements[1].type == ACPI_TYPE_INTEGER &&84 obj->package.elements[2].type == ACPI_TYPE_INTEGER) {85 if (obj->package.elements[0].integer.value)86 size = -EFAULT;87 else {88 req = obj->package.elements[1].integer.value;89 if (tpm_ppi_req_has_parameter(req))90 size = scnprintf(buf, PAGE_SIZE,91 "%llu %llu\n", req,92 obj->package.elements[2].integer.value);93 else94 size = scnprintf(buf, PAGE_SIZE,95 "%llu\n", req);96 }97 } else if (obj->package.count == 2 &&98 obj->package.elements[0].type == ACPI_TYPE_INTEGER &&99 obj->package.elements[1].type == ACPI_TYPE_INTEGER) {100 if (obj->package.elements[0].integer.value)101 size = -EFAULT;102 else103 size = scnprintf(buf, PAGE_SIZE, "%llu\n",104 obj->package.elements[1].integer.value);105 }106 107 ACPI_FREE(obj);108 109 return size;110}111 112static ssize_t tpm_store_ppi_request(struct device *dev,113 struct device_attribute *attr,114 const char *buf, size_t count)115{116 u32 req;117 u64 ret;118 int func = TPM_PPI_FN_SUBREQ;119 union acpi_object *obj, tmp[2];120 union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(2, tmp);121 struct tpm_chip *chip = to_tpm_chip(dev);122 u64 rev = TPM_PPI_REVISION_ID_1;123 124 /*125 * the function to submit TPM operation request to pre-os environment126 * is updated with function index from SUBREQ to SUBREQ2 since PPI127 * version 1.1128 */129 if (acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,130 TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_SUBREQ2))131 func = TPM_PPI_FN_SUBREQ2;132 133 /*134 * PPI spec defines params[3].type as ACPI_TYPE_PACKAGE. Some BIOS135 * accept buffer/string/integer type, but some BIOS accept buffer/136 * string/package type. For PPI version 1.0 and 1.1, use buffer type137 * for compatibility, and use package type since 1.2 according to spec.138 */139 if (strcmp(chip->ppi_version, "1.3") == 0) {140 if (sscanf(buf, "%llu %llu", &tmp[0].integer.value,141 &tmp[1].integer.value) != 2)142 goto ppi12;143 rev = TPM_PPI_REVISION_ID_2;144 tmp[0].type = ACPI_TYPE_INTEGER;145 tmp[1].type = ACPI_TYPE_INTEGER;146 } else if (strcmp(chip->ppi_version, "1.2") < 0) {147 if (sscanf(buf, "%d", &req) != 1)148 return -EINVAL;149 argv4.type = ACPI_TYPE_BUFFER;150 argv4.buffer.length = sizeof(req);151 argv4.buffer.pointer = (u8 *)&req;152 } else {153ppi12:154 argv4.package.count = 1;155 tmp[0].type = ACPI_TYPE_INTEGER;156 if (sscanf(buf, "%llu", &tmp[0].integer.value) != 1)157 return -EINVAL;158 }159 160 obj = tpm_eval_dsm(chip->acpi_dev_handle, func, ACPI_TYPE_INTEGER,161 &argv4, rev);162 if (!obj) {163 return -ENXIO;164 } else {165 ret = obj->integer.value;166 ACPI_FREE(obj);167 }168 169 if (ret == 0)170 return (acpi_status)count;171 172 return (ret == 1) ? -EPERM : -EFAULT;173}174 175static ssize_t tpm_show_ppi_transition_action(struct device *dev,176 struct device_attribute *attr,177 char *buf)178{179 u32 ret;180 acpi_status status;181 union acpi_object *obj = NULL;182 union acpi_object tmp = {183 .buffer.type = ACPI_TYPE_BUFFER,184 .buffer.length = 0,185 .buffer.pointer = NULL186 };187 struct tpm_chip *chip = to_tpm_chip(dev);188 189 static char *info[] = {190 "None",191 "Shutdown",192 "Reboot",193 "OS Vendor-specific",194 "Error",195 };196 197 /*198 * PPI spec defines params[3].type as empty package, but some platforms199 * (e.g. Capella with PPI 1.0) need integer/string/buffer type, so for200 * compatibility, define params[3].type as buffer, if PPI version < 1.2201 */202 if (strcmp(chip->ppi_version, "1.2") < 0)203 obj = &tmp;204 obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETACT,205 ACPI_TYPE_INTEGER, obj, TPM_PPI_REVISION_ID_1);206 if (!obj) {207 return -ENXIO;208 } else {209 ret = obj->integer.value;210 ACPI_FREE(obj);211 }212 213 if (ret < ARRAY_SIZE(info) - 1)214 status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);215 else216 status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,217 info[ARRAY_SIZE(info)-1]);218 return status;219}220 221static ssize_t tpm_show_ppi_response(struct device *dev,222 struct device_attribute *attr,223 char *buf)224{225 acpi_status status = -EINVAL;226 union acpi_object *obj, *ret_obj;227 u64 req, res;228 struct tpm_chip *chip = to_tpm_chip(dev);229 230 obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETRSP,231 ACPI_TYPE_PACKAGE, NULL, TPM_PPI_REVISION_ID_1);232 if (!obj)233 return -ENXIO;234 235 /*236 * parameter output.pointer should be of package type, including237 * 3 integers. The first means function return code, the second means238 * most recent TPM operation request, and the last means response to239 * the most recent TPM operation request. Only if the first is 0, and240 * the second integer is not 0, the response makes sense.241 */242 ret_obj = obj->package.elements;243 if (obj->package.count < 3 ||244 ret_obj[0].type != ACPI_TYPE_INTEGER ||245 ret_obj[1].type != ACPI_TYPE_INTEGER ||246 ret_obj[2].type != ACPI_TYPE_INTEGER)247 goto cleanup;248 249 if (ret_obj[0].integer.value) {250 status = -EFAULT;251 goto cleanup;252 }253 254 req = ret_obj[1].integer.value;255 res = ret_obj[2].integer.value;256 if (req) {257 if (res == 0)258 status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,259 "0: Success");260 else if (res == 0xFFFFFFF0)261 status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,262 "0xFFFFFFF0: User Abort");263 else if (res == 0xFFFFFFF1)264 status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,265 "0xFFFFFFF1: BIOS Failure");266 else if (res >= 1 && res <= 0x00000FFF)267 status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",268 req, res, "Corresponding TPM error");269 else270 status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",271 req, res, "Error");272 } else {273 status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",274 req, "No Recent Request");275 }276 277cleanup:278 ACPI_FREE(obj);279 return status;280}281 282static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,283 u32 end)284{285 int i;286 u32 ret;287 char *str = buf;288 union acpi_object *obj, tmp;289 union acpi_object argv = ACPI_INIT_DSM_ARGV4(1, &tmp);290 291 static char *info[] = {292 "Not implemented",293 "BIOS only",294 "Blocked for OS by BIOS",295 "User required",296 "User not required",297 };298 299 if (!acpi_check_dsm(dev_handle, &tpm_ppi_guid, TPM_PPI_REVISION_ID_1,300 1 << TPM_PPI_FN_GETOPR))301 return -EPERM;302 303 tmp.integer.type = ACPI_TYPE_INTEGER;304 for (i = start; i <= end; i++) {305 tmp.integer.value = i;306 obj = tpm_eval_dsm(dev_handle, TPM_PPI_FN_GETOPR,307 ACPI_TYPE_INTEGER, &argv,308 TPM_PPI_REVISION_ID_1);309 if (!obj) {310 return -ENOMEM;311 } else {312 ret = obj->integer.value;313 ACPI_FREE(obj);314 }315 316 if (ret > 0 && ret < ARRAY_SIZE(info))317 str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",318 i, ret, info[ret]);319 }320 321 return str - buf;322}323 324static ssize_t tpm_show_ppi_tcg_operations(struct device *dev,325 struct device_attribute *attr,326 char *buf)327{328 struct tpm_chip *chip = to_tpm_chip(dev);329 330 return show_ppi_operations(chip->acpi_dev_handle, buf, 0,331 PPI_TPM_REQ_MAX);332}333 334static ssize_t tpm_show_ppi_vs_operations(struct device *dev,335 struct device_attribute *attr,336 char *buf)337{338 struct tpm_chip *chip = to_tpm_chip(dev);339 340 return show_ppi_operations(chip->acpi_dev_handle, buf, PPI_VS_REQ_START,341 PPI_VS_REQ_END);342}343 344static DEVICE_ATTR(version, S_IRUGO, tpm_show_ppi_version, NULL);345static DEVICE_ATTR(request, S_IRUGO | S_IWUSR | S_IWGRP,346 tpm_show_ppi_request, tpm_store_ppi_request);347static DEVICE_ATTR(transition_action, S_IRUGO,348 tpm_show_ppi_transition_action, NULL);349static DEVICE_ATTR(response, S_IRUGO, tpm_show_ppi_response, NULL);350static DEVICE_ATTR(tcg_operations, S_IRUGO, tpm_show_ppi_tcg_operations, NULL);351static DEVICE_ATTR(vs_operations, S_IRUGO, tpm_show_ppi_vs_operations, NULL);352 353static struct attribute *ppi_attrs[] = {354 &dev_attr_version.attr,355 &dev_attr_request.attr,356 &dev_attr_transition_action.attr,357 &dev_attr_response.attr,358 &dev_attr_tcg_operations.attr,359 &dev_attr_vs_operations.attr, NULL,360};361static const struct attribute_group ppi_attr_grp = {362 .name = "ppi",363 .attrs = ppi_attrs364};365 366void tpm_add_ppi(struct tpm_chip *chip)367{368 union acpi_object *obj;369 370 if (!chip->acpi_dev_handle)371 return;372 373 if (!acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,374 TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_VERSION))375 return;376 377 /* Cache PPI version string. */378 obj = acpi_evaluate_dsm_typed(chip->acpi_dev_handle, &tpm_ppi_guid,379 TPM_PPI_REVISION_ID_1,380 TPM_PPI_FN_VERSION,381 NULL, ACPI_TYPE_STRING);382 if (obj) {383 strscpy(chip->ppi_version, obj->string.pointer,384 sizeof(chip->ppi_version));385 ACPI_FREE(obj);386 }387 388 chip->groups[chip->groups_cnt++] = &ppi_attr_grp;389}390