// SPDX-License-Identifier: GPL-2.0
/*
* Intel Platform Monitory Technology Telemetry driver
*
* Copyright (c) 2020, Intel Corporation.
* All Rights Reserved.
*
* Author: "Alexander Duyck" <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/intel_vsec.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include "class.h"
#define PMT_XA_START 1
#define PMT_XA_MAX INT_MAX
#define PMT_XA_LIMIT XA_LIMIT(PMT_XA_START, PMT_XA_MAX)
#define GUID_SPR_PUNIT 0x9956f43f
bool intel_pmt_is_early_client_hw(struct device *dev)
{
struct intel_vsec_device *ivdev = dev_to_ivdev(dev);
/*
* Early implementations of PMT on client platforms have some
* differences from the server platforms (which use the Out Of Band
* Management Services Module OOBMSM).
*/
return !!(ivdev->quirks & VSEC_QUIRK_EARLY_HW);
}
EXPORT_SYMBOL_NS_GPL(intel_pmt_is_early_client_hw, INTEL_PMT);
static inline int
pmt_memcpy64_fromio(void *to, const u64 __iomem *from, size_t count)
{
int i, remain;
u64 *buf = to;
if (!IS_ALIGNED((unsigned long)from, 8))
return -EFAULT;
for (i = 0; i < count/8; i++)
buf[i] = readq(&from[i]);
/* Copy any remaining bytes */
remain = count % 8;
if (remain) {
u64 tmp = readq(&from[i]);
memcpy(&buf[i], &tmp, remain);
}
return count;
}
int pmt_telem_read_mmio(struct pci_dev *pdev, struct pmt_callbacks *cb, u32 guid, void *buf,
void __iomem *addr, u32 count)
{
if (cb && cb->read_telem)
return cb->read_telem(pdev, guid, buf, count);
if (guid == GUID_SPR_PUNIT)
/* PUNIT on SPR only supports aligned 64-bit read */
return pmt_memcpy64_fromio(buf, addr, count);
memcpy_fromio(buf, addr, count);
return count;
}
EXPORT_SYMBOL_NS_GPL(pmt_telem_read_mmio, INTEL_PMT);
/*
* sysfs
*/
static ssize_t
intel_pmt_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf, loff_t off,
size_t count)
{
struct intel_pmt_entry *entry = container_of(attr,
struct intel_pmt_entry,
pmt_bin_attr);
if (off < 0)
return -EINVAL;
if (off >= entry->size)
return 0;
if (count > entry->size - off)
count = entry->size - off;
count = pmt_telem_read_mmio(entry->ep->pcidev, entry->cb, entry->header.guid, buf,
entry->base + off, count);
return count;
}
static int
intel_pmt_mmap(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, struct vm_area_struct *vma)
{
struct intel_pmt_entry *entry = container_of(attr,
struct intel_pmt_entry,
pmt_bin_attr);
unsigned long vsize = vma->vm_end - vma->vm_start;
struct device *dev = kobj_to_dev(kobj);
unsigned long phys = entry->base_addr;
unsigned long pfn = PFN_DOWN(phys);
unsigned long psize;
if (vma->vm_flags & (VM_WRITE | VM_MAYWRITE))
return -EROFS;
psize = (PFN_UP(entry->base_addr + entry->size) - pfn) * PAGE_SIZE;
if (vsize > psize) {
dev_err(dev, "Requested mmap size is too large\n");
return -EINVAL;
}
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
if (io_remap_pfn_range(vma, vma->vm_start, pfn,
vsize, vma->vm_page_prot))
return -EAGAIN;
return 0;
}
static ssize_t
guid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct intel_pmt_entry *entry = dev_get_drvdata(dev);
return sprintf(buf, "0x%x\n", entry->guid);
}
static DEVICE_ATTR_RO(guid);
static ssize_t size_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct intel_pmt_entry *entry = dev_get_drvdata(dev);
return sprintf(buf, "%zu\n", entry->size);
}
static DEVICE_ATTR_RO(size);
static ssize_t
offset_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct intel_pmt_entry *entry = dev_get_drvdata(dev);
return sprintf(buf, "%lu\n", offset_in_page(entry->base_addr));
}
static DEVICE_ATTR_RO(offset);
static struct attribute *intel_pmt_attrs[] = {
&dev_attr_guid.attr,
&dev_attr_size.attr,
&dev_attr_offset.attr,
NULL
};
ATTRIBUTE_GROUPS(intel_pmt);
static struct class intel_pmt_class = {
.name = "intel_pmt",
.dev_groups = intel_pmt_groups,
};
static int intel_pmt_populate_entry(struct intel_pmt_entry *entry,
struct intel_vsec_device *ivdev,
struct resource *disc_res)
{
struct pci_dev *pci_dev = ivdev->pcidev;
struct device *dev = &ivdev->auxdev.dev;
struct intel_pmt_header *header = &entry->header;
u8 bir;
/*
* The base offset should always be 8 byte aligned.
*
* For non-local access types the lower 3 bits of base offset
* contains the index of the base address register where the
* telemetry can be found.
*/
bir = GET_BIR(header->base_offset);
/* Local access and BARID only for now */
switch (header->access_type) {
case ACCESS_LOCAL:
if (bir) {
dev_err(dev,
"Unsupported BAR index %d for access type %d\n",
bir, header->access_type);
return -EINVAL;
}
/*
* For access_type LOCAL, the base address is as follows:
* base address = end of discovery region + base offset
*/
entry->base_addr = disc_res->end + 1 + header->base_offset;
/*
* Some hardware use a different calculation for the base address
* when access_type == ACCESS_LOCAL. On the these systems
* ACCCESS_LOCAL refers to an address in the same BAR as the
* header but at a fixed offset. But as the header address was
* supplied to the driver, we don't know which BAR it was in.
* So search for the bar whose range includes the header address.
*/
if (intel_pmt_is_early_client_hw(dev)) {
int i;
entry->base_addr = 0;
for (i = 0; i < 6; i++)
if (disc_res->start >= pci_resource_start(pci_dev, i) &&
(disc_res->start <= pci_resource_end(pci_dev, i))) {
entry->base_addr = pci_resource_start(pci_dev, i) +
header->base_offset;
break;
}
if (!entry->base_addr)
return -EINVAL;
}
break;
case ACCESS_BARID:
/* Use the provided base address if it exists */
if (ivdev->base_addr) {
entry->base_addr = ivdev->base_addr +
GET_ADDRESS(header->base_offset);
break;
}
/*
* If another BAR was specified then the base offset
* represents the offset within that BAR. SO retrieve the
* address from the parent PCI device and add offset.
*/
entry->base_addr = pci_resource_start(pci_dev, bir) +
GET_ADDRESS(header->base_offset);
break;
default:
dev_err(dev, "Unsupported access type %d\n",
header->access_type);
return -EINVAL;
}
entry->guid = header->guid;
entry->size = header->size;
entry->cb = ivdev->priv_data;
return 0;
}
static int intel_pmt_dev_register(struct intel_pmt_entry *entry,
struct intel_pmt_namespace *ns,
struct device *parent)
{
struct intel_vsec_device *ivdev = dev_to_ivdev(parent);
struct resource res = {0};
struct device *dev;
int ret;
ret = xa_alloc(ns->xa, &entry->devid, entry, PMT_XA_LIMIT, GFP_KERNEL);
if (ret)
return ret;
dev = device_create(&intel_pmt_class, parent, MKDEV(0, 0), entry,
"%s%d", ns->name, entry->devid);
if (IS_ERR(dev)) {
dev_err(parent, "Could not create %s%d device node\n",
ns->name, entry->devid);
ret = PTR_ERR(dev);
goto fail_dev_create;
}
entry->kobj = &dev->kobj;
if (ns->attr_grp) {
ret = sysfs_create_group(entry->kobj, ns->attr_grp);
if (ret)
goto fail_sysfs_create_group;
}
/* if size is 0 assume no data buffer, so no file needed */
if (!entry->size)
return 0;
res.start = entry->base_addr;
res.end = res.start + entry->size - 1;
res.flags = IORESOURCE_MEM;
entry->base = devm_ioremap_resource(dev, &res);
if (IS_ERR(entry->base)) {
ret = PTR_ERR(entry->base);
goto fail_ioremap;
}
sysfs_bin_attr_init(&entry->pmt_bin_attr);
entry->pmt_bin_attr.attr.name = ns->name;
entry->pmt_bin_attr.attr.mode = 0440;
entry->pmt_bin_attr.mmap = intel_pmt_mmap;
entry->pmt_bin_attr.read = intel_pmt_read;
entry->pmt_bin_attr.size = entry->size;
ret = sysfs_create_bin_file(&dev->kobj, &entry->pmt_bin_attr);
if (ret)
goto fail_ioremap;
if (ns->pmt_add_endpoint) {
ret = ns->pmt_add_endpoint(ivdev, entry);
if (ret)
goto fail_add_endpoint;
}
return 0;
fail_add_endpoint:
sysfs_remove_bin_file(entry->kobj, &entry->pmt_bin_attr);
fail_ioremap:
if (ns->attr_grp)
sysfs_remove_group(entry->kobj, ns->attr_grp);
fail_sysfs_create_group:
device_unregister(dev);
fail_dev_create:
xa_erase(ns->xa, entry->devid);
return ret;
}
int intel_pmt_dev_create(struct intel_pmt_entry *entry, struct intel_pmt_namespace *ns,
struct intel_vsec_device *intel_vsec_dev, int idx)
{
struct device *dev = &intel_vsec_dev->auxdev.dev;
struct resource *disc_res;
int ret;
disc_res = &intel_vsec_dev->resource[idx];
entry->disc_table = devm_ioremap_resource(dev, disc_res);
if (IS_ERR(entry->disc_table))
return PTR_ERR(entry->disc_table);
ret = ns->pmt_header_decode(entry, dev);
if (ret)
return ret;
ret = intel_pmt_populate_entry(entry, intel_vsec_dev, disc_res);
if (ret)
return ret;
return intel_pmt_dev_register(entry, ns, dev);
}
EXPORT_SYMBOL_NS_GPL(intel_pmt_dev_create, INTEL_PMT);
void intel_pmt_dev_destroy(struct intel_pmt_entry *entry,
struct intel_pmt_namespace *ns)
{
struct device *dev = kobj_to_dev(entry->kobj);
if (entry->size)
sysfs_remove_bin_file(entry->kobj, &entry->pmt_bin_attr);
if (ns->attr_grp)
sysfs_remove_group(entry->kobj, ns->attr_grp);
device_unregister(dev);
xa_erase(ns->xa, entry->devid);
}
EXPORT_SYMBOL_NS_GPL(intel_pmt_dev_destroy, INTEL_PMT);
static int __init pmt_class_init(void)
{
return class_register(&intel_pmt_class);
}
static void __exit pmt_class_exit(void)
{
class_unregister(&intel_pmt_class);
}
module_init(pmt_class_init);
module_exit(pmt_class_exit);
MODULE_AUTHOR("Alexander Duyck <[email protected]>");
MODULE_DESCRIPTION("Intel PMT Class driver");
MODULE_LICENSE("GPL v2");
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