linux-stable/drivers/misc/ocxl/sysfs.c
Philippe Bergheaud 87db7579eb ocxl: control via sysfs whether the FPGA is reloaded on a link reset
Some opencapi FPGA images allow to control if the FPGA should be reloaded
on the next adapter reset. If it is supported, the image specifies it
through a Vendor Specific DVSEC in the config space of function 0.

Signed-off-by: Philippe Bergheaud <felix@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200619140439.153962-1-fbarrat@linux.ibm.com
2020-07-15 11:07:19 +10:00

186 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
// Copyright 2017 IBM Corp.
#include <linux/sysfs.h>
#include "ocxl_internal.h"
static inline struct ocxl_afu *to_afu(struct device *device)
{
struct ocxl_file_info *info = container_of(device, struct ocxl_file_info, dev);
return info->afu;
}
static ssize_t global_mmio_size_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct ocxl_afu *afu = to_afu(device);
return scnprintf(buf, PAGE_SIZE, "%d\n",
afu->config.global_mmio_size);
}
static ssize_t pp_mmio_size_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct ocxl_afu *afu = to_afu(device);
return scnprintf(buf, PAGE_SIZE, "%d\n",
afu->config.pp_mmio_stride);
}
static ssize_t afu_version_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct ocxl_afu *afu = to_afu(device);
return scnprintf(buf, PAGE_SIZE, "%hhu:%hhu\n",
afu->config.version_major,
afu->config.version_minor);
}
static ssize_t contexts_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct ocxl_afu *afu = to_afu(device);
return scnprintf(buf, PAGE_SIZE, "%d/%d\n",
afu->pasid_count, afu->pasid_max);
}
static ssize_t reload_on_reset_show(struct device *device,
struct device_attribute *attr,
char *buf)
{
struct ocxl_afu *afu = to_afu(device);
struct ocxl_fn *fn = afu->fn;
struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
int val;
if (ocxl_config_get_reset_reload(pci_dev, &val))
return scnprintf(buf, PAGE_SIZE, "unavailable\n");
return scnprintf(buf, PAGE_SIZE, "%d\n", val);
}
static ssize_t reload_on_reset_store(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ocxl_afu *afu = to_afu(device);
struct ocxl_fn *fn = afu->fn;
struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
int rc, val;
rc = kstrtoint(buf, 0, &val);
if (rc || (val != 0 && val != 1))
return -EINVAL;
if (ocxl_config_set_reset_reload(pci_dev, val))
return -ENODEV;
return count;
}
static struct device_attribute afu_attrs[] = {
__ATTR_RO(global_mmio_size),
__ATTR_RO(pp_mmio_size),
__ATTR_RO(afu_version),
__ATTR_RO(contexts),
__ATTR_RW(reload_on_reset),
};
static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
if (count == 0 || off < 0 ||
off >= afu->config.global_mmio_size)
return 0;
memcpy_fromio(buf, afu->global_mmio_ptr + off, count);
return count;
}
static vm_fault_t global_mmio_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct ocxl_afu *afu = vma->vm_private_data;
unsigned long offset;
if (vmf->pgoff >= (afu->config.global_mmio_size >> PAGE_SHIFT))
return VM_FAULT_SIGBUS;
offset = vmf->pgoff;
offset += (afu->global_mmio_start >> PAGE_SHIFT);
return vmf_insert_pfn(vma, vmf->address, offset);
}
static const struct vm_operations_struct global_mmio_vmops = {
.fault = global_mmio_fault,
};
static int global_mmio_mmap(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
struct vm_area_struct *vma)
{
struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
if ((vma_pages(vma) + vma->vm_pgoff) >
(afu->config.global_mmio_size >> PAGE_SHIFT))
return -EINVAL;
vma->vm_flags |= VM_IO | VM_PFNMAP;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
vma->vm_ops = &global_mmio_vmops;
vma->vm_private_data = afu;
return 0;
}
int ocxl_sysfs_register_afu(struct ocxl_file_info *info)
{
int i, rc;
for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
rc = device_create_file(&info->dev, &afu_attrs[i]);
if (rc)
goto err;
}
sysfs_attr_init(&info->attr_global_mmio.attr);
info->attr_global_mmio.attr.name = "global_mmio_area";
info->attr_global_mmio.attr.mode = 0600;
info->attr_global_mmio.size = info->afu->config.global_mmio_size;
info->attr_global_mmio.read = global_mmio_read;
info->attr_global_mmio.mmap = global_mmio_mmap;
rc = device_create_bin_file(&info->dev, &info->attr_global_mmio);
if (rc) {
dev_err(&info->dev, "Unable to create global mmio attr for afu: %d\n", rc);
goto err;
}
return 0;
err:
for (i--; i >= 0; i--)
device_remove_file(&info->dev, &afu_attrs[i]);
return rc;
}
void ocxl_sysfs_unregister_afu(struct ocxl_file_info *info)
{
int i;
/*
* device_remove_bin_file is safe to call if the file is not added as
* the files are removed by name, and early exit if not found
*/
for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
device_remove_file(&info->dev, &afu_attrs[i]);
device_remove_bin_file(&info->dev, &info->attr_global_mmio);
}