// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012-2014 Intel Corporation
*
* Authors:
* Xiaoyan Zhang <[email protected]>
* Jiang Liu <[email protected]>
* Jarkko Sakkinen <[email protected]>
*
* Maintained by: <[email protected]>
*
* This file contains implementation of the sysfs interface for PPI.
*/
#include <linux/acpi.h>
#include "tpm.h"
#define TPM_PPI_REVISION_ID_1 1
#define TPM_PPI_REVISION_ID_2 2
#define TPM_PPI_FN_VERSION 1
#define TPM_PPI_FN_SUBREQ 2
#define TPM_PPI_FN_GETREQ 3
#define TPM_PPI_FN_GETACT 4
#define TPM_PPI_FN_GETRSP 5
#define TPM_PPI_FN_SUBREQ2 7
#define TPM_PPI_FN_GETOPR 8
#define PPI_TPM_REQ_MAX 101 /* PPI 1.3 for TPM 2 */
#define PPI_VS_REQ_START 128
#define PPI_VS_REQ_END 255
static const guid_t tpm_ppi_guid =
GUID_INIT(0x3DDDFAA6, 0x361B, 0x4EB4,
0xA4, 0x24, 0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53);
static bool tpm_ppi_req_has_parameter(u64 req)
{
return req == 23;
}
static inline union acpi_object *
tpm_eval_dsm(acpi_handle ppi_handle, int func, acpi_object_type type,
union acpi_object *argv4, u64 rev)
{
BUG_ON(!ppi_handle);
return acpi_evaluate_dsm_typed(ppi_handle, &tpm_ppi_guid,
rev, func, argv4, type);
}
static ssize_t tpm_show_ppi_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
}
static ssize_t tpm_show_ppi_request(struct device *dev,
struct device_attribute *attr, char *buf)
{
ssize_t size = -EINVAL;
union acpi_object *obj;
struct tpm_chip *chip = to_tpm_chip(dev);
u64 rev = TPM_PPI_REVISION_ID_2;
u64 req;
if (strcmp(chip->ppi_version, "1.2") < 0)
rev = TPM_PPI_REVISION_ID_1;
obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETREQ,
ACPI_TYPE_PACKAGE, NULL, rev);
if (!obj)
return -ENXIO;
/*
* output.pointer should be of package type, including two integers.
* The first is function return code, 0 means success and 1 means
* error. The second is pending TPM operation requested by the OS, 0
* means none and >0 means operation value.
*/
if (obj->package.count == 3 &&
obj->package.elements[0].type == ACPI_TYPE_INTEGER &&
obj->package.elements[1].type == ACPI_TYPE_INTEGER &&
obj->package.elements[2].type == ACPI_TYPE_INTEGER) {
if (obj->package.elements[0].integer.value)
size = -EFAULT;
else {
req = obj->package.elements[1].integer.value;
if (tpm_ppi_req_has_parameter(req))
size = scnprintf(buf, PAGE_SIZE,
"%llu %llu\n", req,
obj->package.elements[2].integer.value);
else
size = scnprintf(buf, PAGE_SIZE,
"%llu\n", req);
}
} else if (obj->package.count == 2 &&
obj->package.elements[0].type == ACPI_TYPE_INTEGER &&
obj->package.elements[1].type == ACPI_TYPE_INTEGER) {
if (obj->package.elements[0].integer.value)
size = -EFAULT;
else
size = scnprintf(buf, PAGE_SIZE, "%llu\n",
obj->package.elements[1].integer.value);
}
ACPI_FREE(obj);
return size;
}
static ssize_t tpm_store_ppi_request(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
u32 req;
u64 ret;
int func = TPM_PPI_FN_SUBREQ;
union acpi_object *obj, tmp[2];
union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(2, tmp);
struct tpm_chip *chip = to_tpm_chip(dev);
u64 rev = TPM_PPI_REVISION_ID_1;
/*
* the function to submit TPM operation request to pre-os environment
* is updated with function index from SUBREQ to SUBREQ2 since PPI
* version 1.1
*/
if (acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,
TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_SUBREQ2))
func = TPM_PPI_FN_SUBREQ2;
/*
* PPI spec defines params[3].type as ACPI_TYPE_PACKAGE. Some BIOS
* accept buffer/string/integer type, but some BIOS accept buffer/
* string/package type. For PPI version 1.0 and 1.1, use buffer type
* for compatibility, and use package type since 1.2 according to spec.
*/
if (strcmp(chip->ppi_version, "1.3") == 0) {
if (sscanf(buf, "%llu %llu", &tmp[0].integer.value,
&tmp[1].integer.value) != 2)
goto ppi12;
rev = TPM_PPI_REVISION_ID_2;
tmp[0].type = ACPI_TYPE_INTEGER;
tmp[1].type = ACPI_TYPE_INTEGER;
} else if (strcmp(chip->ppi_version, "1.2") < 0) {
if (sscanf(buf, "%d", &req) != 1)
return -EINVAL;
argv4.type = ACPI_TYPE_BUFFER;
argv4.buffer.length = sizeof(req);
argv4.buffer.pointer = (u8 *)&req;
} else {
ppi12:
argv4.package.count = 1;
tmp[0].type = ACPI_TYPE_INTEGER;
if (sscanf(buf, "%llu", &tmp[0].integer.value) != 1)
return -EINVAL;
}
obj = tpm_eval_dsm(chip->acpi_dev_handle, func, ACPI_TYPE_INTEGER,
&argv4, rev);
if (!obj) {
return -ENXIO;
} else {
ret = obj->integer.value;
ACPI_FREE(obj);
}
if (ret == 0)
return (acpi_status)count;
return (ret == 1) ? -EPERM : -EFAULT;
}
static ssize_t tpm_show_ppi_transition_action(struct device *dev,
struct device_attribute *attr,
char *buf)
{
u32 ret;
acpi_status status;
union acpi_object *obj = NULL;
union acpi_object tmp = {
.buffer.type = ACPI_TYPE_BUFFER,
.buffer.length = 0,
.buffer.pointer = NULL
};
struct tpm_chip *chip = to_tpm_chip(dev);
static char *info[] = {
"None",
"Shutdown",
"Reboot",
"OS Vendor-specific",
"Error",
};
/*
* PPI spec defines params[3].type as empty package, but some platforms
* (e.g. Capella with PPI 1.0) need integer/string/buffer type, so for
* compatibility, define params[3].type as buffer, if PPI version < 1.2
*/
if (strcmp(chip->ppi_version, "1.2") < 0)
obj = &tmp;
obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETACT,
ACPI_TYPE_INTEGER, obj, TPM_PPI_REVISION_ID_1);
if (!obj) {
return -ENXIO;
} else {
ret = obj->integer.value;
ACPI_FREE(obj);
}
if (ret < ARRAY_SIZE(info) - 1)
status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
else
status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
info[ARRAY_SIZE(info)-1]);
return status;
}
static ssize_t tpm_show_ppi_response(struct device *dev,
struct device_attribute *attr,
char *buf)
{
acpi_status status = -EINVAL;
union acpi_object *obj, *ret_obj;
u64 req, res;
struct tpm_chip *chip = to_tpm_chip(dev);
obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETRSP,
ACPI_TYPE_PACKAGE, NULL, TPM_PPI_REVISION_ID_1);
if (!obj)
return -ENXIO;
/*
* parameter output.pointer should be of package type, including
* 3 integers. The first means function return code, the second means
* most recent TPM operation request, and the last means response to
* the most recent TPM operation request. Only if the first is 0, and
* the second integer is not 0, the response makes sense.
*/
ret_obj = obj->package.elements;
if (obj->package.count < 3 ||
ret_obj[0].type != ACPI_TYPE_INTEGER ||
ret_obj[1].type != ACPI_TYPE_INTEGER ||
ret_obj[2].type != ACPI_TYPE_INTEGER)
goto cleanup;
if (ret_obj[0].integer.value) {
status = -EFAULT;
goto cleanup;
}
req = ret_obj[1].integer.value;
res = ret_obj[2].integer.value;
if (req) {
if (res == 0)
status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
"0: Success");
else if (res == 0xFFFFFFF0)
status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
"0xFFFFFFF0: User Abort");
else if (res == 0xFFFFFFF1)
status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
"0xFFFFFFF1: BIOS Failure");
else if (res >= 1 && res <= 0x00000FFF)
status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
req, res, "Corresponding TPM error");
else
status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
req, res, "Error");
} else {
status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
req, "No Recent Request");
}
cleanup:
ACPI_FREE(obj);
return status;
}
static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
u32 end)
{
int i;
u32 ret;
char *str = buf;
union acpi_object *obj, tmp;
union acpi_object argv = ACPI_INIT_DSM_ARGV4(1, &tmp);
static char *info[] = {
"Not implemented",
"BIOS only",
"Blocked for OS by BIOS",
"User required",
"User not required",
};
if (!acpi_check_dsm(dev_handle, &tpm_ppi_guid, TPM_PPI_REVISION_ID_1,
1 << TPM_PPI_FN_GETOPR))
return -EPERM;
tmp.integer.type = ACPI_TYPE_INTEGER;
for (i = start; i <= end; i++) {
tmp.integer.value = i;
obj = tpm_eval_dsm(dev_handle, TPM_PPI_FN_GETOPR,
ACPI_TYPE_INTEGER, &argv,
TPM_PPI_REVISION_ID_1);
if (!obj) {
return -ENOMEM;
} else {
ret = obj->integer.value;
ACPI_FREE(obj);
}
if (ret > 0 && ret < ARRAY_SIZE(info))
str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
i, ret, info[ret]);
}
return str - buf;
}
static ssize_t tpm_show_ppi_tcg_operations(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
return show_ppi_operations(chip->acpi_dev_handle, buf, 0,
PPI_TPM_REQ_MAX);
}
static ssize_t tpm_show_ppi_vs_operations(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
return show_ppi_operations(chip->acpi_dev_handle, buf, PPI_VS_REQ_START,
PPI_VS_REQ_END);
}
static DEVICE_ATTR(version, S_IRUGO, tpm_show_ppi_version, NULL);
static DEVICE_ATTR(request, S_IRUGO | S_IWUSR | S_IWGRP,
tpm_show_ppi_request, tpm_store_ppi_request);
static DEVICE_ATTR(transition_action, S_IRUGO,
tpm_show_ppi_transition_action, NULL);
static DEVICE_ATTR(response, S_IRUGO, tpm_show_ppi_response, NULL);
static DEVICE_ATTR(tcg_operations, S_IRUGO, tpm_show_ppi_tcg_operations, NULL);
static DEVICE_ATTR(vs_operations, S_IRUGO, tpm_show_ppi_vs_operations, NULL);
static struct attribute *ppi_attrs[] = {
&dev_attr_version.attr,
&dev_attr_request.attr,
&dev_attr_transition_action.attr,
&dev_attr_response.attr,
&dev_attr_tcg_operations.attr,
&dev_attr_vs_operations.attr, NULL,
};
static const struct attribute_group ppi_attr_grp = {
.name = "ppi",
.attrs = ppi_attrs
};
void tpm_add_ppi(struct tpm_chip *chip)
{
union acpi_object *obj;
if (!chip->acpi_dev_handle)
return;
if (!acpi_check_dsm(chip->acpi_dev_handle, &tpm_ppi_guid,
TPM_PPI_REVISION_ID_1, 1 << TPM_PPI_FN_VERSION))
return;
/* Cache PPI version string. */
obj = acpi_evaluate_dsm_typed(chip->acpi_dev_handle, &tpm_ppi_guid,
TPM_PPI_REVISION_ID_1,
TPM_PPI_FN_VERSION,
NULL, ACPI_TYPE_STRING);
if (obj) {
strscpy(chip->ppi_version, obj->string.pointer,
sizeof(chip->ppi_version));
ACPI_FREE(obj);
}
chip->groups[chip->groups_cnt++] = &ppi_attr_grp;
}
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