[PATCH v2 4/5] drivers/acpi: Introduce Platform Firmware Runtime Update Telemetry

[Chen Yu]

Platform Firmware Runtime Update(PFRU) Telemetry Service is part of RoT
(Root of Trust), which allows PFRU handler and other PFRU drivers to
produce telemetry data to upper layer OS consumer at runtime.

The linux provides interfaces for the user to query the parameters of
telemetry data, and the user could read out the telemetry data
accordingly.

Typical log looks like:

[SmmRuntimeUpdateHandler.ProcessSmmRuntimeUpdate]
ProcessSmmRuntimeUpdate = START, Action = 2
[SmmRuntimeUpdateHandler.ProcessSmmRuntimeUpdate]
FwVersion = 0, CodeInjectionVersion = 1
[ShadowSmmRuntimeUpdateImage]
Image = 0x74D9B000, ImageSize = 0x1172
[ProcessSmmRuntimeUpdate]
ShadowSmmRuntimeUpdateImage.Status = Success
[ValidateSmmRuntimeUpdateImage]
CapsuleHeader.CapsuleGuid = 6DCBD5ED-E82D-4C44-BDA1-7194199AD92A
[ValidateSmmRuntimeUpdateImage]
FmpCapHeader.Version = 1
[ValidateSmmRuntimeUpdateImage]
FmpCapImageHeader.UpdateImageTypeId = B2F84B79-7B6E-4E45-885F-3FB9BB185402
[ValidateSmmRuntimeUpdateImage]
SmmRuntimeUpdateVerifyImageWithDenylist.Status = Success
[ValidateSmmRuntimeUpdateImage]
SmmRuntimeUpdateVerifyImageWithAllowlist.Status = Success
[SmmCodeInjectionVerifyPayloadHeader]
PayloadHeader.Signature = 0x31494353
[SmmCodeInjectionVerifyPayloadHeader]
PayloadHeader.PlatformId = 63462139-A8B1-AA4E-9024-F2BB53EA4723
[SmmCodeInjectionVerifyPayloadHeader]
PayloadHeader.SupportedSmmFirmwareVersion = 0,
PayloadHeader.SmmCodeInjectionRuntimeVersion = 1
[ProcessSmmRuntimeUpdate]
ValidateSmmRuntimeUpdateImage.Status = Success
CPU CSR[0B102D28] Before = 7FBF830E
CPU CSR[0B102D28] After = 7FBF8310
[ProcessSmmRuntimeUpdate] ProcessSmmCodeInjection.Status = Success
[SmmRuntimeUpdateHandler.ProcessSmmRuntimeUpdate]
ProcessSmmRuntimeUpdate = End, Status = Success

Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
---
v2:  Do similar clean up as pfru_update driver:
     Add sanity check for duplicated instance of ACPI device.
     Update the driver to work with allocated telem_device objects.
     (Mike Rapoport)
     For each switch case pair, get rid of the magic case numbers
     and add a default clause with the error handling.
     (Mike Rapoport)
---
 drivers/acpi/pfru/Kconfig          |  14 +
 drivers/acpi/pfru/Makefile         |   1 +
 drivers/acpi/pfru/pfru_telemetry.c | 412 +++++++++++++++++++++++++++++
 include/uapi/linux/pfru.h          |  46 ++++
 4 files changed, 473 insertions(+)
 create mode 100644 drivers/acpi/pfru/pfru_telemetry.c

diff --git a/drivers/acpi/pfru/Kconfig b/drivers/acpi/pfru/Kconfig
index 3f31b7d95f3b..e2934058884e 100644
--- a/drivers/acpi/pfru/Kconfig
+++ b/drivers/acpi/pfru/Kconfig
@@ -13,3 +13,17 @@ config ACPI_PFRU
 
 	  To compile this driver as a module, choose M here:
 	  the module will be called pfru_update.
+
+config ACPI_PFRU_TELEMETRY
+	tristate "ACPI Platform Firmware Runtime Update Telemetry Service"
+	depends on ACPI_PFRU
+	help
+	  PFRU(Platform Firmware Runtime Update) Telemetry Service is part of
+	  RoT(Root of Trust), which allows Platform Firmware Runtime Update handler
+	  and other PFRU drivers to produce telemetry data to upper layer OS consumer
+	  at runtime.
+
+	  For more information, see:
+	  <file:Documentation/x86/pfru_update.rst>
+
+	  If unsure, please say N.
diff --git a/drivers/acpi/pfru/Makefile b/drivers/acpi/pfru/Makefile
index 098cbe80cf3d..30060ba320ea 100644
--- a/drivers/acpi/pfru/Makefile
+++ b/drivers/acpi/pfru/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_ACPI_PFRU) += pfru_update.o
+obj-$(CONFIG_ACPI_PFRU_TELEMETRY) += pfru_telemetry.o
diff --git a/drivers/acpi/pfru/pfru_telemetry.c b/drivers/acpi/pfru/pfru_telemetry.c
new file mode 100644
index 000000000000..bab8b2b548aa
--- /dev/null
+++ b/drivers/acpi/pfru/pfru_telemetry.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ACPI Platform Firmware Runtime Update
+ * Telemetry Service Device Driver
+ *
+ * Copyright (C) 2021 Intel Corporation
+ * Author: Chen Yu <yu.c.chen@xxxxxxxxx>
+ */
+#include <linux/acpi.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/minmax.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/platform_device.h>
+#include <linux/uuid.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/pfru.h>
+
+enum update_index {
+	LOG_STATUS_IDX,
+	LOG_EXT_STATUS_IDX,
+	LOG_MAX_SZ_IDX,
+	LOG_CHUNK1_LO_IDX,
+	LOG_CHUNK1_HI_IDX,
+	LOG_CHUNK1_SZ_IDX,
+	LOG_CHUNK2_LO_IDX,
+	LOG_CHUNK2_HI_IDX,
+	LOG_CHUNK2_SZ_IDX,
+	LOG_ROLLOVER_CNT_IDX,
+	LOG_RESET_CNT_IDX,
+};
+
+struct pfru_telem_device {
+	struct device *dev;
+	guid_t uuid;
+	struct telem_info info;
+};
+
+/*
+ * There would be only one instance of pfru_telem_device.
+ */
+static struct pfru_telem_device *telem_dev;
+
+static int get_pfru_data_info(struct telem_data_info *data_info,
+			      int log_type)
+{
+	union acpi_object *out_obj, in_obj, in_buf;
+	acpi_handle handle;
+	int i, ret = -EINVAL;
+
+	handle = ACPI_HANDLE(telem_dev->dev);
+
+	memset(&in_obj, 0, sizeof(in_obj));
+	memset(&in_buf, 0, sizeof(in_buf));
+	in_obj.type = ACPI_TYPE_PACKAGE;
+	in_obj.package.count = 1;
+	in_obj.package.elements = &in_buf;
+	in_buf.type = ACPI_TYPE_INTEGER;
+	in_buf.integer.value = log_type;
+
+	out_obj = acpi_evaluate_dsm_typed(handle, &telem_dev->uuid,
+					  telem_dev->info.log_revid, FUNC_GET_DATA,
+					  &in_obj, ACPI_TYPE_PACKAGE);
+	if (!out_obj) {
+		pr_err("Failed to invoke _DSM\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < out_obj->package.count; i++) {
+		union acpi_object *obj = &out_obj->package.elements[i];
+
+		if (obj->type != ACPI_TYPE_INTEGER)
+			goto free_acpi_buffer;
+
+		switch (i) {
+		case LOG_STATUS_IDX:
+			data_info->status = obj->integer.value;
+			break;
+		case LOG_EXT_STATUS_IDX:
+			data_info->ext_status = obj->integer.value;
+			break;
+		case LOG_MAX_SZ_IDX:
+			data_info->max_data_size = obj->integer.value;
+			break;
+		case LOG_CHUNK1_LO_IDX:
+			data_info->chunk1_addr_lo = obj->integer.value;
+			break;
+		case LOG_CHUNK1_HI_IDX:
+			data_info->chunk1_addr_hi = obj->integer.value;
+			break;
+		case LOG_CHUNK1_SZ_IDX:
+			data_info->chunk1_size = obj->integer.value;
+			break;
+		case LOG_CHUNK2_LO_IDX:
+			data_info->chunk2_addr_lo = obj->integer.value;
+			break;
+		case LOG_CHUNK2_HI_IDX:
+			data_info->chunk2_addr_hi = obj->integer.value;
+			break;
+		case LOG_CHUNK2_SZ_IDX:
+			data_info->chunk2_size = obj->integer.value;
+			break;
+		case LOG_ROLLOVER_CNT_IDX:
+			data_info->rollover_cnt = obj->integer.value;
+			break;
+		case LOG_RESET_CNT_IDX:
+			data_info->reset_cnt = obj->integer.value;
+			break;
+		default:
+			pr_err("Incorrect format of Telemetry info.\n");
+			goto free_acpi_buffer;
+		}
+	}
+	ret = 0;
+
+free_acpi_buffer:
+	ACPI_FREE(out_obj);
+
+	return ret;
+}
+
+static int set_pfru_log_level(int level)
+{
+	union acpi_object *out_obj, *obj, in_obj, in_buf;
+	enum dsm_status status;
+	acpi_handle handle;
+	int ret = -EINVAL;
+
+	handle = ACPI_HANDLE(telem_dev->dev);
+
+	memset(&in_obj, 0, sizeof(in_obj));
+	memset(&in_buf, 0, sizeof(in_buf));
+	in_obj.type = ACPI_TYPE_PACKAGE;
+	in_obj.package.count = 1;
+	in_obj.package.elements = &in_buf;
+	in_buf.type = ACPI_TYPE_INTEGER;
+	in_buf.integer.value = level;
+
+	out_obj = acpi_evaluate_dsm_typed(handle, &telem_dev->uuid,
+					  telem_dev->info.log_revid, FUNC_SET_LEV,
+					  &in_obj, ACPI_TYPE_PACKAGE);
+	if (!out_obj)
+		return -EINVAL;
+
+	obj = &out_obj->package.elements[0];
+	status = obj->integer.value;
+	if (status) {
+		pr_err("get MM telemetry level error status %d\n",
+		       status);
+		goto free_acpi_buffer;
+	}
+
+	obj = &out_obj->package.elements[1];
+	status = obj->integer.value;
+	if (status) {
+		pr_err("get MM telemetry level error extend status %d\n",
+		       status);
+		goto free_acpi_buffer;
+	}
+	ret = 0;
+
+free_acpi_buffer:
+	ACPI_FREE(out_obj);
+
+	return ret;
+}
+
+static int get_pfru_log_level(int *level)
+{
+	union acpi_object *out_obj, *obj;
+	enum dsm_status status;
+	acpi_handle handle;
+	int ret = -EINVAL;
+
+	handle = ACPI_HANDLE(telem_dev->dev);
+	out_obj = acpi_evaluate_dsm_typed(handle, &telem_dev->uuid,
+					  telem_dev->info.log_revid, FUNC_GET_LEV,
+					  NULL, ACPI_TYPE_PACKAGE);
+	if (!out_obj)
+		return -EINVAL;
+
+	obj = &out_obj->package.elements[0];
+	if (obj->type != ACPI_TYPE_INTEGER)
+		goto free_acpi_buffer;
+	status = obj->integer.value;
+	if (status) {
+		pr_err("get MM telemetry level error status %d\n",
+		       status);
+		goto free_acpi_buffer;
+	}
+
+	obj = &out_obj->package.elements[1];
+	if (obj->type != ACPI_TYPE_INTEGER)
+		goto free_acpi_buffer;
+	status = obj->integer.value;
+	if (status) {
+		pr_err("get MM telemetry level error status %d\n",
+		       status);
+		goto free_acpi_buffer;
+	}
+
+	obj = &out_obj->package.elements[2];
+	if (obj->type != ACPI_TYPE_INTEGER)
+		goto free_acpi_buffer;
+	*level = obj->integer.value;
+
+	ret = 0;
+
+free_acpi_buffer:
+	ACPI_FREE(out_obj);
+
+	return ret;
+}
+
+static int valid_log_level(int level)
+{
+	return (level == LOG_ERR) || (level == LOG_WARN) ||
+		(level == LOG_INFO) || (level == LOG_VERB);
+}
+
+static int valid_log_type(int type)
+{
+	return (type == LOG_EXEC_IDX) || (type == LOG_HISTORY_IDX);
+}
+
+static long pfru_telemetry_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+
+{
+	struct telem_data_info data_info;
+	struct telem_info info;
+	void __user *p;
+	int ret = 0;
+
+	p = (void __user *)arg;
+
+	switch (cmd) {
+	case PFRU_LOG_IOC_SET_INFO:
+		if (copy_from_user(&info, p, sizeof(info)))
+			return -EFAULT;
+		if (valid_revid(info.log_revid))
+			telem_dev->info.log_revid = info.log_revid;
+
+		if (valid_log_level(info.log_level)) {
+			ret = set_pfru_log_level(info.log_level);
+			if (ret)
+				return ret;
+			telem_dev->info.log_level = info.log_level;
+		}
+		if (valid_log_type(info.log_type))
+			telem_dev->info.log_type = info.log_type;
+		break;
+	case PFRU_LOG_IOC_GET_INFO:
+		ret = get_pfru_log_level(&info.log_level);
+		if (ret)
+			return ret;
+		info.log_type = telem_dev->info.log_type;
+		info.log_revid = telem_dev->info.log_revid;
+		if (copy_to_user(p, &info, sizeof(info)))
+			ret = -EFAULT;
+		break;
+	case PFRU_LOG_IOC_GET_DATA_INFO:
+		ret = get_pfru_data_info(&data_info, telem_dev->info.log_type);
+		if (ret)
+			return ret;
+		if (copy_to_user(p, &data_info, sizeof(struct telem_data_info)))
+			ret = -EFAULT;
+		break;
+	default:
+		ret = -ENOIOCTLCMD;
+		break;
+	}
+	return ret;
+}
+
+static ssize_t pfru_telemetry_read(struct file *filp, char __user *ubuf,
+				   size_t size, loff_t *off)
+{
+	struct telem_data_info info;
+	phys_addr_t base_addr;
+	int buf_size, ret;
+	char *buf_ptr;
+
+	if (*off < 0)
+		return -EINVAL;
+
+	ret = get_pfru_data_info(&info, telem_dev->info.log_type);
+	if (ret) {
+		pr_err("Could not get telemetry data info %d\n", ret);
+		return ret;
+	}
+
+	base_addr = (phys_addr_t)(info.chunk2_addr_lo |
+			(info.chunk2_addr_hi << 32));
+	if (!base_addr) {
+		pr_err("Telemetry data not ready\n");
+		return -EBUSY;
+	}
+
+	buf_size = info.max_data_size;
+	if (*off >= buf_size)
+		return 0;
+
+	buf_ptr = memremap(base_addr, buf_size, MEMREMAP_WB);
+	if (IS_ERR(buf_ptr))
+		return PTR_ERR(buf_ptr);
+
+	size = min_t(size_t, size, buf_size - *off);
+
+	ret = -EFAULT;
+	if (copy_to_user(ubuf, buf_ptr + *off, size))
+		goto out;
+	ret = 0;
+out:
+	memunmap(buf_ptr);
+
+	return ret ? ret : size;
+}
+
+#ifdef CONFIG_COMPAT
+static long compat_pfru_telemetry_ioctl(struct file *filep, unsigned int cmd,
+					unsigned long arg)
+{
+	return pfru_telemetry_ioctl(filep, cmd, arg);
+}
+#endif
+
+static const struct file_operations acpi_pfru_telemetry_fops = {
+	.owner		= THIS_MODULE,
+	.read		= pfru_telemetry_read,
+	.unlocked_ioctl = pfru_telemetry_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= compat_pfru_telemetry_ioctl,
+#endif
+	.llseek		= noop_llseek,
+};
+
+static struct miscdevice pfru_telemetry_misc_dev = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "pfru_telemetry",
+	.nodename = "pfru/telemetry",
+	.fops = &acpi_pfru_telemetry_fops,
+};
+
+static int acpi_pfru_telemetry_remove(struct platform_device *pdev)
+{
+	misc_deregister(&pfru_telemetry_misc_dev);
+	kfree(telem_dev);
+	telem_dev = NULL;
+
+	return 0;
+}
+
+static int acpi_pfru_telemetry_probe(struct platform_device *pdev)
+{
+	acpi_handle handle;
+	int ret;
+
+	if (telem_dev) {
+		pr_err("Duplicated PFRU Telemetry INTC1081 detected, skip...\n");
+		return 0;
+	}
+
+	telem_dev = kzalloc(sizeof(*telem_dev), GFP_KERNEL);
+	if (!telem_dev)
+		return -ENOMEM;
+
+	ret = guid_parse(PFRU_TELEMETRY_UUID, &telem_dev->uuid);
+	if (ret)
+		goto out;
+
+	telem_dev->info.log_revid = 1;
+	telem_dev->dev = &pdev->dev;
+	handle = ACPI_HANDLE(telem_dev->dev);
+	if (!acpi_has_method(handle, "_DSM")) {
+		pr_err("Missing _DSM\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	ret = misc_register(&pfru_telemetry_misc_dev);
+	if (ret)
+		goto out;
+
+	return 0;
+out:
+	kfree(telem_dev);
+	telem_dev = NULL;
+
+	return ret;
+}
+
+static const struct acpi_device_id acpi_pfru_telemetry_ids[] = {
+	{"INTC1081", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(acpi, acpi_pfru_telemetry_ids);
+
+static struct platform_driver acpi_pfru_telemetry_driver = {
+	.driver = {
+		.name = "pfru_telemetry",
+		.acpi_match_table = acpi_pfru_telemetry_ids,
+	},
+	.probe = acpi_pfru_telemetry_probe,
+	.remove = acpi_pfru_telemetry_remove,
+};
+module_platform_driver(acpi_pfru_telemetry_driver);
+
+MODULE_DESCRIPTION("Platform Firmware Runtime Update Telemetry Service device driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/pfru.h b/include/uapi/linux/pfru.h
index 4db85458dae2..b5786b51c611 100644
--- a/include/uapi/linux/pfru.h
+++ b/include/uapi/linux/pfru.h
@@ -98,4 +98,50 @@ struct updated_result {
 	unsigned long high_exec_time;
 };
 
+#define PFRU_TELEMETRY_UUID	"75191659-8178-4D9D-B88F-AC5E5E93E8BF"
+
+/* Telemetry structures. */
+struct telem_data_info {
+	enum dsm_status status;
+	enum dsm_status ext_status;
+	/*
+	 * Maximum chunk data size.
+	 */
+	unsigned long chunk1_addr_lo;
+	unsigned long chunk1_addr_hi;
+	unsigned long chunk2_addr_lo;
+	unsigned long chunk2_addr_hi;
+	int max_data_size;
+	int chunk1_size;
+	int chunk2_size;
+	int rollover_cnt;
+	int reset_cnt;
+};
+
+struct telem_info {
+	int log_level;
+	int log_type;
+	int log_revid;
+};
+
+/* Two logs: history and execution log */
+#define LOG_EXEC_IDX	0
+#define LOG_HISTORY_IDX	1
+#define NR_LOG_TYPE	2
+
+#define LOG_ERR		0
+#define LOG_WARN	1
+#define LOG_INFO	2
+#define LOG_VERB	4
+
+#define FUNC_SET_LEV		1
+#define FUNC_GET_LEV		2
+#define FUNC_GET_DATA		3
+
+#define LOG_NAME_SIZE		10
+
+#define PFRU_LOG_IOC_SET_INFO _IOW(PFRU_MAGIC, 0x05, struct telem_info)
+#define PFRU_LOG_IOC_GET_INFO _IOR(PFRU_MAGIC, 0x06, struct telem_info)
+#define PFRU_LOG_IOC_GET_DATA_INFO _IOR(PFRU_MAGIC, 0x07, struct telem_data_info)
+
 #endif /* __PFRU_H__ */
-- 
2.25.1