Commit d3a23584 authored by Srinivas Pandruvada's avatar Srinivas Pandruvada Committed by Andy Shevchenko
Browse files

platform/x86: ISST: Add Intel Speed Select mmio interface 



Added MMIO interface to read/write specific offsets in PUNIT PCI device
which export core priortization. This MMIO interface can be used using
ioctl interface on /dev/isst_interface using IOCTL ISST_IF_IO_CMD.

This MMIO interface is used by the intel-speed-select tool under
tools/x86/power to enumerate and set core priority. The MMIO offsets and
semantics of the message can be checked from the source code of the tool.

Signed-off-by: default avatarSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
parent fb5b36a4

drivers/platform/x86/intel_speed_select_if/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -5,3 +5,4 @@ 
#



obj-$(CONFIG_INTEL_SPEED_SELECT_INTERFACE) += isst_if_common.o

obj-$(CONFIG_INTEL_SPEED_SELECT_INTERFACE) += isst_if_mmio.o

drivers/platform/x86/intel_speed_select_if/isst_if_common.c

+6 −0
Original line number Diff line number Diff line
@@ -206,6 +206,7 @@ static long isst_if_def_ioctl(struct file *file, unsigned int cmd, 
{

	void __user *argp = (void __user *)arg;

	struct isst_if_cmd_cb cmd_cb;

	struct isst_if_cmd_cb *cb;

	long ret = -ENOTTY;



	switch (cmd) {
@@ -218,6 +219,11 @@ static long isst_if_def_ioctl(struct file *file, unsigned int cmd, 
		cmd_cb.cmd_callback = isst_if_proc_phyid_req;

		ret = isst_if_exec_multi_cmd(argp, &cmd_cb);

		break;

	case ISST_IF_IO_CMD:

		cb = &punit_callbacks[ISST_IF_DEV_MMIO];

		if (cb->registered)

			ret = isst_if_exec_multi_cmd(argp, cb);

		break;

	default:

		break;

	}

drivers/platform/x86/intel_speed_select_if/isst_if_common.h

+2 −0
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ 
#ifndef __ISST_IF_COMMON_H

#define __ISST_IF_COMMON_H



#define INTEL_RAPL_PRIO_DEVID_0	0x3451



/*

 * Validate maximum commands in a single request.

 * This is enough to handle command to every core in one ioctl, or all

drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c

0 → 100644
+131 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Intel Speed Select Interface: MMIO Interface

 * Copyright (c) 2019, Intel Corporation.

 * All rights reserved.

 *

 * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

 */



#include <linux/module.h>

#include <linux/pci.h>

#include <linux/sched/signal.h>

#include <linux/uaccess.h>

#include <uapi/linux/isst_if.h>



#include "isst_if_common.h"



struct isst_if_device {

	void __iomem *punit_mmio;

	struct mutex mutex;

};



static long isst_if_mmio_rd_wr(u8 *cmd_ptr, int *write_only, int resume)

{

	struct isst_if_device *punit_dev;

	struct isst_if_io_reg *io_reg;

	struct pci_dev *pdev;



	io_reg = (struct isst_if_io_reg *)cmd_ptr;

	if (io_reg->reg < 0x04 || io_reg->reg > 0xD0)

		return -EINVAL;



	if (io_reg->read_write && !capable(CAP_SYS_ADMIN))

		return -EPERM;



	pdev = isst_if_get_pci_dev(io_reg->logical_cpu, 0, 0, 1);

	if (!pdev)

		return -EINVAL;



	punit_dev = pci_get_drvdata(pdev);

	if (!punit_dev)

		return -EINVAL;



	/*

	 * Ensure that operation is complete on a PCI device to avoid read

	 * write race by using per PCI device mutex.

	 */

	mutex_lock(&punit_dev->mutex);

	if (io_reg->read_write) {

		writel(io_reg->value, punit_dev->punit_mmio+io_reg->reg);

		*write_only = 1;

	} else {

		io_reg->value = readl(punit_dev->punit_mmio+io_reg->reg);

		*write_only = 0;

	}

	mutex_unlock(&punit_dev->mutex);



	return 0;

}



static const struct pci_device_id isst_if_ids[] = {

	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, INTEL_RAPL_PRIO_DEVID_0)},

	{ 0 },

};

MODULE_DEVICE_TABLE(pci, isst_if_ids);



static int isst_if_probe(struct pci_dev *pdev, const struct pci_device_id *ent)

{

	struct isst_if_device *punit_dev;

	struct isst_if_cmd_cb cb;

	u32 mmio_base, pcu_base;

	u64 base_addr;

	int ret;



	punit_dev = devm_kzalloc(&pdev->dev, sizeof(*punit_dev), GFP_KERNEL);

	if (!punit_dev)

		return -ENOMEM;



	ret = pcim_enable_device(pdev);

	if (ret)

		return ret;



	ret = pci_read_config_dword(pdev, 0xD0, &mmio_base);

	if (ret)

		return ret;



	ret = pci_read_config_dword(pdev, 0xFC, &pcu_base);

	if (ret)

		return ret;



	pcu_base &= GENMASK(10, 0);

	base_addr = (u64)mmio_base << 23 | (u64) pcu_base << 12;

	punit_dev->punit_mmio = devm_ioremap(&pdev->dev, base_addr, 256);

	if (!punit_dev->punit_mmio)

		return -ENOMEM;



	mutex_init(&punit_dev->mutex);

	pci_set_drvdata(pdev, punit_dev);



	memset(&cb, 0, sizeof(cb));

	cb.cmd_size = sizeof(struct isst_if_io_reg);

	cb.offset = offsetof(struct isst_if_io_regs, io_reg);

	cb.cmd_callback = isst_if_mmio_rd_wr;

	cb.owner = THIS_MODULE;

	ret = isst_if_cdev_register(ISST_IF_DEV_MMIO, &cb);

	if (ret)

		mutex_destroy(&punit_dev->mutex);



	return ret;

}



static void isst_if_remove(struct pci_dev *pdev)

{

	struct isst_if_device *punit_dev;



	punit_dev = pci_get_drvdata(pdev);

	isst_if_cdev_unregister(ISST_IF_DEV_MBOX);

	mutex_destroy(&punit_dev->mutex);

}



static struct pci_driver isst_if_pci_driver = {

	.name			= "isst_if_pci",

	.id_table		= isst_if_ids,

	.probe			= isst_if_probe,

	.remove			= isst_if_remove,

};



module_pci_driver(isst_if_pci_driver);



MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("Intel speed select interface mmio driver");

include/uapi/linux/isst_if.h

+33 −0
Original line number Diff line number Diff line
@@ -63,7 +63,40 @@ struct isst_if_cpu_maps { 
	struct isst_if_cpu_map cpu_map[1];

};



/**

 * struct isst_if_io_reg - Read write PUNIT IO register

 * @read_write:		Value 0: Read, 1: Write

 * @logical_cpu:	Logical CPU number to get target PCI device.

 * @reg:		PUNIT register offset

 * @value:		For write operation value to write and for

 *			for read placeholder read value

 *

 * Structure to specify read/write data to PUNIT registers.

 */

struct isst_if_io_reg {

	__u32 read_write; /* Read:0, Write:1 */

	__u32 logical_cpu;

	__u32 reg;

	__u32 value;

};



/**

 * struct isst_if_io_regs - structure for IO register commands

 * @cmd_count:	Number of io reg commands in io_reg[]

 * @io_reg[]:	Holds one or more io_reg command structure

 *

 * This structure used with ioctl ISST_IF_IO_CMD to send

 * one or more read/write commands to PUNIT. Here IOCTL return value

 * indicates number of requests sent or error number if no requests have

 * been sent.

 */

struct isst_if_io_regs {

	__u32 req_count;

	struct isst_if_io_reg io_reg[1];

};



#define ISST_IF_MAGIC			0xFE

#define ISST_IF_GET_PLATFORM_INFO	_IOR(ISST_IF_MAGIC, 0, struct isst_if_platform_info *)

#define ISST_IF_GET_PHY_ID		_IOWR(ISST_IF_MAGIC, 1, struct isst_if_cpu_map *)

#define ISST_IF_IO_CMD		_IOW(ISST_IF_MAGIC, 2, struct isst_if_io_regs *)

#endif

CRA Git | Maintained and supported by SUSTech CRA and CCSE