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: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This commit is contained in:
Srinivas Pandruvada 2019-06-26 15:38:46 -07:00 committed by Andy Shevchenko
parent fb5b36a413
commit d3a2358429
5 changed files with 173 additions and 0 deletions

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@ -5,3 +5,4 @@
#
obj-$(CONFIG_INTEL_SPEED_SELECT_INTERFACE) += isst_if_common.o
obj-$(CONFIG_INTEL_SPEED_SELECT_INTERFACE) += isst_if_mmio.o

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@ -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;
}

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@ -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

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@ -0,0 +1,131 @@
// 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");

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@ -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