Commit 68fe8e6e authored by Alexander Duyck's avatar Alexander Duyck Committed by Lee Jones
Browse files

platform/x86: Intel PMT Telemetry capability driver 



PMT Telemetry is a capability of the Intel Platform Monitoring Technology.
The Telemetry capability provides access to device telemetry metrics that
provide hardware performance data to users from read-only register spaces.

With this driver present the intel_pmt directory can be populated with
telem<x> devices. These devices will contain the standard intel_pmt sysfs
data and a "telem" binary sysfs attribute which can be used to access the
telemetry data.

Also create a PCI device id list for early telemetry hardware that require
workarounds for known issues.

Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@linux.intel.com>
Co-developed-by: default avatarDavid E. Box <david.e.box@linux.intel.com>
Signed-off-by: default avatarDavid E. Box <david.e.box@linux.intel.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent e2729113

drivers/platform/x86/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -1374,6 +1374,17 @@ config INTEL_PMT_CLASS 
	  To compile this driver as a module, choose M here: the module

	  will be called intel_pmt_class.



config INTEL_PMT_TELEMETRY

	tristate "Intel Platform Monitoring Technology (PMT) Telemetry driver"

	select INTEL_PMT_CLASS

	help

	  The Intel Platform Monitory Technology (PMT) Telemetry driver provides

	  access to hardware telemetry metrics on devices that support the

	  feature.



	  To compile this driver as a module, choose M here: the module

	  will be called intel_pmt_telemetry.



config INTEL_PUNIT_IPC

	tristate "Intel P-Unit IPC Driver"

	help

drivers/platform/x86/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -141,6 +141,7 @@ obj-$(CONFIG_INTEL_MID_POWER_BUTTON) += intel_mid_powerbtn.o 
obj-$(CONFIG_INTEL_MRFLD_PWRBTN)	+= intel_mrfld_pwrbtn.o

obj-$(CONFIG_INTEL_PMC_CORE)		+= intel_pmc_core.o intel_pmc_core_pltdrv.o

obj-$(CONFIG_INTEL_PMT_CLASS)		+= intel_pmt_class.o

obj-$(CONFIG_INTEL_PMT_TELEMETRY)	+= intel_pmt_telemetry.o

obj-$(CONFIG_INTEL_PUNIT_IPC)		+= intel_punit_ipc.o

obj-$(CONFIG_INTEL_SCU_IPC)		+= intel_scu_ipc.o

obj-$(CONFIG_INTEL_SCU_PCI)		+= intel_scu_pcidrv.o

drivers/platform/x86/intel_pmt_telemetry.c

0 → 100644
+160 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Intel Platform Monitory Technology Telemetry driver

 *

 * Copyright (c) 2020, Intel Corporation.

 * All Rights Reserved.

 *

 * Author: "David E. Box" <david.e.box@linux.intel.com>

 */



#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/pci.h>

#include <linux/slab.h>

#include <linux/uaccess.h>

#include <linux/overflow.h>



#include "intel_pmt_class.h"



#define TELEM_DEV_NAME		"pmt_telemetry"



#define TELEM_SIZE_OFFSET	0x0

#define TELEM_GUID_OFFSET	0x4

#define TELEM_BASE_OFFSET	0x8

#define TELEM_ACCESS(v)		((v) & GENMASK(3, 0))

/* size is in bytes */

#define TELEM_SIZE(v)		(((v) & GENMASK(27, 12)) >> 10)



/* Used by client hardware to identify a fixed telemetry entry*/

#define TELEM_CLIENT_FIXED_BLOCK_GUID	0x10000000



struct pmt_telem_priv {

	int				num_entries;

	struct intel_pmt_entry		entry[];

};



/*

 * Early implementations of PMT on client platforms have some

 * differences from the server platforms (which use the Out Of Band

 * Management Services Module OOBMSM). This list tracks those

 * platforms as needed to handle those differences. Newer client

 * platforms are expected to be fully compatible with server.

 */

static const struct pci_device_id pmt_telem_early_client_pci_ids[] = {

	{ PCI_VDEVICE(INTEL, 0x9a0d) }, /* TGL */

	{ PCI_VDEVICE(INTEL, 0x467d) }, /* ADL */

	{ }

};



static bool intel_pmt_is_early_client_hw(struct device *dev)

{

	struct pci_dev *parent = to_pci_dev(dev->parent);



	return !!pci_match_id(pmt_telem_early_client_pci_ids, parent);

}



static bool pmt_telem_region_overlaps(struct intel_pmt_entry *entry,

				      struct device *dev)

{

	u32 guid = readl(entry->disc_table + TELEM_GUID_OFFSET);



	if (guid != TELEM_CLIENT_FIXED_BLOCK_GUID)

		return false;



	return intel_pmt_is_early_client_hw(dev);

}



static int pmt_telem_header_decode(struct intel_pmt_entry *entry,

				   struct intel_pmt_header *header,

				   struct device *dev)

{

	void __iomem *disc_table = entry->disc_table;



	if (pmt_telem_region_overlaps(entry, dev))

		return 1;



	header->access_type = TELEM_ACCESS(readl(disc_table));

	header->guid = readl(disc_table + TELEM_GUID_OFFSET);

	header->base_offset = readl(disc_table + TELEM_BASE_OFFSET);



	/* Size is measured in DWORDS, but accessor returns bytes */

	header->size = TELEM_SIZE(readl(disc_table));



	return 0;

}



static DEFINE_XARRAY_ALLOC(telem_array);

static struct intel_pmt_namespace pmt_telem_ns = {

	.name = "telem",

	.xa = &telem_array,

	.pmt_header_decode = pmt_telem_header_decode,

};



static int pmt_telem_remove(struct platform_device *pdev)

{

	struct pmt_telem_priv *priv = platform_get_drvdata(pdev);

	int i;



	for (i = 0; i < priv->num_entries; i++)

		intel_pmt_dev_destroy(&priv->entry[i], &pmt_telem_ns);



	return 0;

}



static int pmt_telem_probe(struct platform_device *pdev)

{

	struct pmt_telem_priv *priv;

	size_t size;

	int i, ret;



	size = struct_size(priv, entry, pdev->num_resources);

	priv = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);

	if (!priv)

		return -ENOMEM;



	platform_set_drvdata(pdev, priv);



	for (i = 0; i < pdev->num_resources; i++) {

		struct intel_pmt_entry *entry = &priv->entry[i];



		ret = intel_pmt_dev_create(entry, &pmt_telem_ns, pdev, i);

		if (ret < 0)

			goto abort_probe;

		if (ret)

			continue;



		priv->num_entries++;

	}



	return 0;

abort_probe:

	pmt_telem_remove(pdev);

	return ret;

}



static struct platform_driver pmt_telem_driver = {

	.driver = {

		.name   = TELEM_DEV_NAME,

	},

	.remove = pmt_telem_remove,

	.probe  = pmt_telem_probe,

};



static int __init pmt_telem_init(void)

{

	return platform_driver_register(&pmt_telem_driver);

}

module_init(pmt_telem_init);



static void __exit pmt_telem_exit(void)

{

	platform_driver_unregister(&pmt_telem_driver);

	xa_destroy(&telem_array);

}

module_exit(pmt_telem_exit);



MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");

MODULE_DESCRIPTION("Intel PMT Telemetry driver");

MODULE_ALIAS("platform:" TELEM_DEV_NAME);

MODULE_LICENSE("GPL v2");