platform/x86: Add Intel Telemetry Core Driver

Intel PM Telemetry is a software mechanism via which various SoC
PM and performance related parameters like PM counters, firmware
trace verbosity, the status of different devices inside the SoC, etc.
can be monitored and analyzed. The different samples that may be
monitored can be configured at runtime via exported APIs.

This patch adds the telemetry core driver that implements basic
exported APIs.

Signed-off-by: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

3 files changed, 476 insertions, 0 deletions

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index f37821f004f9..d72b14809d7e 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -977,4 +977,15 @@ config INTEL_PUNIT_IPC
 	---help---
 	  This driver provides support for Intel P-Unit Mailbox IPC mechanism,
 	  which is used to bridge the communications between kernel and P-Unit.
+
+config INTEL_TELEMETRY
+	tristate "Intel SoC Telemetry Driver"
+	default n
+	depends on INTEL_PMC_IPC && INTEL_PUNIT_IPC && X86_64
+	---help---
+	  This driver provides interfaces to configure and use
+	  telemetry for INTEL SoC from APL onwards. It is also
+	  used to get various SoC events and parameters
+	  directly via debugfs files. Various tools may use
+	  this interface for SoC state monitoring.
 endif # X86_PLATFORM_DEVICES
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 8b8df29dc502..9277ce52d375 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -65,3 +65,4 @@ obj-$(CONFIG_ALIENWARE_WMI)	+= alienware-wmi.o
 obj-$(CONFIG_INTEL_PMC_IPC)	+= intel_pmc_ipc.o
 obj-$(CONFIG_SURFACE_PRO3_BUTTON)	+= surfacepro3_button.o
 obj-$(CONFIG_INTEL_PUNIT_IPC)  += intel_punit_ipc.o
+obj-$(CONFIG_INTEL_TELEMETRY)	+= intel_telemetry_core.o
diff --git a/drivers/platform/x86/intel_telemetry_core.c b/drivers/platform/x86/intel_telemetry_core.c
new file mode 100644
index 000000000000..a695a436a1c3
--- /dev/null
+++ b/drivers/platform/x86/intel_telemetry_core.c
@@ -0,0 +1,464 @@
+/*
+ * Intel SoC Core Telemetry Driver
+ * Copyright (C) 2015, Intel Corporation.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * Telemetry Framework provides platform related PM and performance statistics.
+ * This file provides the core telemetry API implementation.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+
+#include <asm/intel_telemetry.h>
+
+#define DRIVER_NAME "intel_telemetry_core"
+
+struct telemetry_core_config {
+	struct telemetry_plt_config *plt_config;
+	struct telemetry_core_ops *telem_ops;
+};
+
+static struct telemetry_core_config telm_core_conf;
+
+static int telemetry_def_update_events(struct telemetry_evtconfig pss_evtconfig,
+				      struct telemetry_evtconfig ioss_evtconfig)
+{
+	return 0;
+}
+
+static int telemetry_def_set_sampling_period(u8 pss_period, u8 ioss_period)
+{
+	return 0;
+}
+
+static int telemetry_def_get_sampling_period(u8 *pss_min_period,
+					     u8 *pss_max_period,
+					     u8 *ioss_min_period,
+					     u8 *ioss_max_period)
+{
+	return 0;
+}
+
+static int telemetry_def_get_eventconfig(
+			struct telemetry_evtconfig *pss_evtconfig,
+			struct telemetry_evtconfig *ioss_evtconfig,
+			int pss_len, int ioss_len)
+{
+	return 0;
+}
+
+static int telemetry_def_get_trace_verbosity(enum telemetry_unit telem_unit,
+					     u32 *verbosity)
+{
+	return 0;
+}
+
+
+static int telemetry_def_set_trace_verbosity(enum telemetry_unit telem_unit,
+					     u32 verbosity)
+{
+	return 0;
+}
+
+static int telemetry_def_raw_read_eventlog(enum telemetry_unit telem_unit,
+					   struct telemetry_evtlog *evtlog,
+					   int len, int log_all_evts)
+{
+	return 0;
+}
+
+static int telemetry_def_read_eventlog(enum telemetry_unit telem_unit,
+				       struct telemetry_evtlog *evtlog,
+				       int len, int log_all_evts)
+{
+	return 0;
+}
+
+static int telemetry_def_add_events(u8 num_pss_evts, u8 num_ioss_evts,
+				    u32 *pss_evtmap, u32 *ioss_evtmap)
+{
+	return 0;
+}
+
+static int telemetry_def_reset_events(void)
+{
+	return 0;
+}
+
+static struct telemetry_core_ops telm_defpltops = {
+	.set_sampling_period = telemetry_def_set_sampling_period,
+	.get_sampling_period = telemetry_def_get_sampling_period,
+	.get_trace_verbosity = telemetry_def_get_trace_verbosity,
+	.set_trace_verbosity = telemetry_def_set_trace_verbosity,
+	.raw_read_eventlog = telemetry_def_raw_read_eventlog,
+	.get_eventconfig = telemetry_def_get_eventconfig,
+	.read_eventlog = telemetry_def_read_eventlog,
+	.update_events = telemetry_def_update_events,
+	.reset_events = telemetry_def_reset_events,
+	.add_events = telemetry_def_add_events,
+};
+
+/**
+ * telemetry_update_events() - Update telemetry Configuration
+ * @pss_evtconfig: PSS related config. No change if num_evts = 0.
+ * @pss_evtconfig: IOSS related config. No change if num_evts = 0.
+ *
+ * This API updates the IOSS & PSS Telemetry configuration. Old config
+ * is overwritten. Call telemetry_reset_events when logging is over
+ * All sample period values should be in the form of:
+ * bits[6:3] -> value; bits [0:2]-> Exponent; Period = (Value *16^Exponent)
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_update_events(struct telemetry_evtconfig pss_evtconfig,
+			    struct telemetry_evtconfig ioss_evtconfig)
+{
+	return telm_core_conf.telem_ops->update_events(pss_evtconfig,
+						       ioss_evtconfig);
+}
+EXPORT_SYMBOL_GPL(telemetry_update_events);
+
+
+/**
+ * telemetry_set_sampling_period() - Sets the IOSS & PSS sampling period
+ * @pss_period:  placeholder for PSS Period to be set.
+ *		 Set to 0 if not required to be updated
+ * @ioss_period: placeholder for IOSS Period to be set
+ *		 Set to 0 if not required to be updated
+ *
+ * All values should be in the form of:
+ * bits[6:3] -> value; bits [0:2]-> Exponent; Period = (Value *16^Exponent)
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_set_sampling_period(u8 pss_period, u8 ioss_period)
+{
+	return telm_core_conf.telem_ops->set_sampling_period(pss_period,
+							     ioss_period);
+}
+EXPORT_SYMBOL_GPL(telemetry_set_sampling_period);
+
+/**
+ * telemetry_get_sampling_period() - Get IOSS & PSS min & max sampling period
+ * @pss_min_period:  placeholder for PSS Min Period supported
+ * @pss_max_period:  placeholder for PSS Max Period supported
+ * @ioss_min_period: placeholder for IOSS Min Period supported
+ * @ioss_max_period: placeholder for IOSS Max Period supported
+ *
+ * All values should be in the form of:
+ * bits[6:3] -> value; bits [0:2]-> Exponent; Period = (Value *16^Exponent)
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_get_sampling_period(u8 *pss_min_period, u8 *pss_max_period,
+				  u8 *ioss_min_period, u8 *ioss_max_period)
+{
+	return telm_core_conf.telem_ops->get_sampling_period(pss_min_period,
+							     pss_max_period,
+							     ioss_min_period,
+							     ioss_max_period);
+}
+EXPORT_SYMBOL_GPL(telemetry_get_sampling_period);
+
+
+/**
+ * telemetry_reset_events() - Restore the IOSS & PSS configuration to default
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_reset_events(void)
+{
+	return telm_core_conf.telem_ops->reset_events();
+}
+EXPORT_SYMBOL_GPL(telemetry_reset_events);
+
+/**
+ * telemetry_get_eventconfig() - Returns the pss and ioss events enabled
+ * @pss_evtconfig: Pointer to PSS related configuration.
+ * @pss_evtconfig: Pointer to IOSS related configuration.
+ * @pss_len:	   Number of u32 elements allocated for pss_evtconfig array
+ * @ioss_len:	   Number of u32 elements allocated for ioss_evtconfig array
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_get_eventconfig(struct telemetry_evtconfig *pss_evtconfig,
+			      struct telemetry_evtconfig *ioss_evtconfig,
+			      int pss_len, int ioss_len)
+{
+	return telm_core_conf.telem_ops->get_eventconfig(pss_evtconfig,
+							 ioss_evtconfig,
+							 pss_len, ioss_len);
+}
+EXPORT_SYMBOL_GPL(telemetry_get_eventconfig);
+
+/**
+ * telemetry_add_events() - Add IOSS & PSS configuration to existing settings.
+ * @num_pss_evts:  Number of PSS Events (<29) in pss_evtmap. Can be 0.
+ * @num_ioss_evts: Number of IOSS Events (<29) in ioss_evtmap. Can be 0.
+ * @pss_evtmap:    Array of PSS Event-IDs to Enable
+ * @ioss_evtmap:   Array of PSS Event-IDs to Enable
+ *
+ * Events are appended to Old Configuration. In case of total events > 28, it
+ * returns error. Call telemetry_reset_events to reset after eventlog done
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_add_events(u8 num_pss_evts, u8 num_ioss_evts,
+			 u32 *pss_evtmap, u32 *ioss_evtmap)
+{
+	return telm_core_conf.telem_ops->add_events(num_pss_evts,
+						    num_ioss_evts, pss_evtmap,
+						    ioss_evtmap);
+}
+EXPORT_SYMBOL_GPL(telemetry_add_events);
+
+/**
+ * telemetry_read_events() - Fetches samples as specified by evtlog.telem_evt_id
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @evtlog:     Array of telemetry_evtlog structs to fill data
+ *		evtlog.telem_evt_id specifies the ids to read
+ * @len:	Length of array of evtlog
+ *
+ * Return: number of eventlogs read for success, < 0 for failure
+ */
+int telemetry_read_events(enum telemetry_unit telem_unit,
+			  struct telemetry_evtlog *evtlog, int len)
+{
+	return telm_core_conf.telem_ops->read_eventlog(telem_unit, evtlog,
+						       len, 0);
+}
+EXPORT_SYMBOL_GPL(telemetry_read_events);
+
+/**
+ * telemetry_raw_read_events() - Fetch samples specified by evtlog.telem_evt_id
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @evtlog:	Array of telemetry_evtlog structs to fill data
+ *		evtlog.telem_evt_id specifies the ids to read
+ * @len:	Length of array of evtlog
+ *
+ * The caller must take care of locking in this case.
+ *
+ * Return: number of eventlogs read for success, < 0 for failure
+ */
+int telemetry_raw_read_events(enum telemetry_unit telem_unit,
+			      struct telemetry_evtlog *evtlog, int len)
+{
+	return telm_core_conf.telem_ops->raw_read_eventlog(telem_unit, evtlog,
+							   len, 0);
+}
+EXPORT_SYMBOL_GPL(telemetry_raw_read_events);
+
+/**
+ * telemetry_read_eventlog() - Fetch the Telemetry log from PSS or IOSS
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @evtlog:	Array of telemetry_evtlog structs to fill data
+ * @len:	Length of array of evtlog
+ *
+ * Return: number of eventlogs read for success, < 0 for failure
+ */
+int telemetry_read_eventlog(enum telemetry_unit telem_unit,
+			    struct telemetry_evtlog *evtlog, int len)
+{
+	return telm_core_conf.telem_ops->read_eventlog(telem_unit, evtlog,
+						       len, 1);
+}
+EXPORT_SYMBOL_GPL(telemetry_read_eventlog);
+
+/**
+ * telemetry_raw_read_eventlog() - Fetch the Telemetry log from PSS or IOSS
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @evtlog:	Array of telemetry_evtlog structs to fill data
+ * @len:	Length of array of evtlog
+ *
+ * The caller must take care of locking in this case.
+ *
+ * Return: number of eventlogs read for success, < 0 for failure
+ */
+int telemetry_raw_read_eventlog(enum telemetry_unit telem_unit,
+				struct telemetry_evtlog *evtlog, int len)
+{
+	return telm_core_conf.telem_ops->raw_read_eventlog(telem_unit, evtlog,
+							   len, 1);
+}
+EXPORT_SYMBOL_GPL(telemetry_raw_read_eventlog);
+
+
+/**
+ * telemetry_get_trace_verbosity() - Get the IOSS & PSS Trace verbosity
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @verbosity:	Pointer to return Verbosity
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_get_trace_verbosity(enum telemetry_unit telem_unit,
+				  u32 *verbosity)
+{
+	return telm_core_conf.telem_ops->get_trace_verbosity(telem_unit,
+							     verbosity);
+}
+EXPORT_SYMBOL_GPL(telemetry_get_trace_verbosity);
+
+
+/**
+ * telemetry_set_trace_verbosity() - Update the IOSS & PSS Trace verbosity
+ * @telem_unit: Specify whether IOSS or PSS Read
+ * @verbosity:	Verbosity to set
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_set_trace_verbosity(enum telemetry_unit telem_unit, u32 verbosity)
+{
+	return telm_core_conf.telem_ops->set_trace_verbosity(telem_unit,
+							     verbosity);
+}
+EXPORT_SYMBOL_GPL(telemetry_set_trace_verbosity);
+
+/**
+ * telemetry_set_pltdata() - Set the platform specific Data
+ * @ops:	Pointer to ops structure
+ * @pltconfig:	Platform config data
+ *
+ * Usage by other than telemetry pltdrv module is invalid
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_set_pltdata(struct telemetry_core_ops *ops,
+			  struct telemetry_plt_config *pltconfig)
+{
+	if (ops)
+		telm_core_conf.telem_ops = ops;
+
+	if (pltconfig)
+		telm_core_conf.plt_config = pltconfig;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(telemetry_set_pltdata);
+
+/**
+ * telemetry_clear_pltdata() - Clear the platform specific Data
+ *
+ * Usage by other than telemetry pltdrv module is invalid
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_clear_pltdata(void)
+{
+	telm_core_conf.telem_ops = &telm_defpltops;
+	telm_core_conf.plt_config = NULL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(telemetry_clear_pltdata);
+
+/**
+ * telemetry_pltconfig_valid() - Checkif platform config is valid
+ *
+ * Usage by other than telemetry module is invalid
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_pltconfig_valid(void)
+{
+	if (telm_core_conf.plt_config)
+		return 0;
+
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(telemetry_pltconfig_valid);
+
+static inline int telemetry_get_pssevtname(enum telemetry_unit telem_unit,
+					   const char **name, int len)
+{
+	struct telemetry_unit_config psscfg;
+	int i;
+
+	if (!telm_core_conf.plt_config)
+		return -EINVAL;
+
+	psscfg = telm_core_conf.plt_config->pss_config;
+
+	if (len > psscfg.ssram_evts_used)
+		len = psscfg.ssram_evts_used;
+
+	for (i = 0; i < len; i++)
+		name[i] = psscfg.telem_evts[i].name;
+
+	return 0;
+}
+
+static inline int telemetry_get_iossevtname(enum telemetry_unit telem_unit,
+					    const char **name, int len)
+{
+	struct telemetry_unit_config iosscfg;
+	int i;
+
+	if (!(telm_core_conf.plt_config))
+		return -EINVAL;
+
+	iosscfg = telm_core_conf.plt_config->ioss_config;
+
+	if (len > iosscfg.ssram_evts_used)
+		len = iosscfg.ssram_evts_used;
+
+	for (i = 0; i < len; i++)
+		name[i] = iosscfg.telem_evts[i].name;
+
+	return 0;
+
+}
+
+/**
+ * telemetry_get_evtname() - Checkif platform config is valid
+ * @telem_unit:	Telemetry Unit to check
+ * @name:	Array of character pointers to contain name
+ * @len:	length of array name provided by user
+ *
+ * Usage by other than telemetry debugfs module is invalid
+ *
+ * Return: 0 success, < 0 for failure
+ */
+int telemetry_get_evtname(enum telemetry_unit telem_unit,
+			  const char **name, int len)
+{
+	int ret = -EINVAL;
+
+	if (telem_unit == TELEM_PSS)
+		ret = telemetry_get_pssevtname(telem_unit, name, len);
+
+	else if (telem_unit == TELEM_IOSS)
+		ret = telemetry_get_iossevtname(telem_unit, name, len);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(telemetry_get_evtname);
+
+static int __init telemetry_module_init(void)
+{
+	pr_info(pr_fmt(DRIVER_NAME) " Init\n");
+
+	telm_core_conf.telem_ops = &telm_defpltops;
+	return 0;
+}
+
+static void __exit telemetry_module_exit(void)
+{
+}
+
+module_init(telemetry_module_init);
+module_exit(telemetry_module_exit);
+
+MODULE_AUTHOR("Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com>");
+MODULE_DESCRIPTION("Intel SoC Telemetry Interface");
+MODULE_LICENSE("GPL");