xref: /openbmc/linux/drivers/misc/ocxl/sysfs.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2017 IBM Corp.
3 #include <linux/sysfs.h>
4 #include "ocxl_internal.h"
5 
6 static inline struct ocxl_afu *to_afu(struct device *device)
7 {
8 	struct ocxl_file_info *info = container_of(device, struct ocxl_file_info, dev);
9 
10 	return info->afu;
11 }
12 
13 static ssize_t global_mmio_size_show(struct device *device,
14 				struct device_attribute *attr,
15 				char *buf)
16 {
17 	struct ocxl_afu *afu = to_afu(device);
18 
19 	return scnprintf(buf, PAGE_SIZE, "%d\n",
20 			afu->config.global_mmio_size);
21 }
22 
23 static ssize_t pp_mmio_size_show(struct device *device,
24 				struct device_attribute *attr,
25 				char *buf)
26 {
27 	struct ocxl_afu *afu = to_afu(device);
28 
29 	return scnprintf(buf, PAGE_SIZE, "%d\n",
30 			afu->config.pp_mmio_stride);
31 }
32 
33 static ssize_t afu_version_show(struct device *device,
34 				struct device_attribute *attr,
35 				char *buf)
36 {
37 	struct ocxl_afu *afu = to_afu(device);
38 
39 	return scnprintf(buf, PAGE_SIZE, "%hhu:%hhu\n",
40 			afu->config.version_major,
41 			afu->config.version_minor);
42 }
43 
44 static ssize_t contexts_show(struct device *device,
45 		struct device_attribute *attr,
46 		char *buf)
47 {
48 	struct ocxl_afu *afu = to_afu(device);
49 
50 	return scnprintf(buf, PAGE_SIZE, "%d/%d\n",
51 			afu->pasid_count, afu->pasid_max);
52 }
53 
54 static ssize_t reload_on_reset_show(struct device *device,
55 				    struct device_attribute *attr,
56 				    char *buf)
57 {
58 	struct ocxl_afu *afu = to_afu(device);
59 	struct ocxl_fn *fn = afu->fn;
60 	struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
61 	int val;
62 
63 	if (ocxl_config_get_reset_reload(pci_dev, &val))
64 		return scnprintf(buf, PAGE_SIZE, "unavailable\n");
65 
66 	return scnprintf(buf, PAGE_SIZE, "%d\n", val);
67 }
68 
69 static ssize_t reload_on_reset_store(struct device *device,
70 				     struct device_attribute *attr,
71 				     const char *buf, size_t count)
72 {
73 	struct ocxl_afu *afu = to_afu(device);
74 	struct ocxl_fn *fn = afu->fn;
75 	struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
76 	int rc, val;
77 
78 	rc = kstrtoint(buf, 0, &val);
79 	if (rc || (val != 0 && val != 1))
80 		return -EINVAL;
81 
82 	if (ocxl_config_set_reset_reload(pci_dev, val))
83 		return -ENODEV;
84 
85 	return count;
86 }
87 
88 static struct device_attribute afu_attrs[] = {
89 	__ATTR_RO(global_mmio_size),
90 	__ATTR_RO(pp_mmio_size),
91 	__ATTR_RO(afu_version),
92 	__ATTR_RO(contexts),
93 	__ATTR_RW(reload_on_reset),
94 };
95 
96 static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
97 				struct bin_attribute *bin_attr, char *buf,
98 				loff_t off, size_t count)
99 {
100 	struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
101 
102 	if (count == 0 || off < 0 ||
103 		off >= afu->config.global_mmio_size)
104 		return 0;
105 	memcpy_fromio(buf, afu->global_mmio_ptr + off, count);
106 	return count;
107 }
108 
109 static vm_fault_t global_mmio_fault(struct vm_fault *vmf)
110 {
111 	struct vm_area_struct *vma = vmf->vma;
112 	struct ocxl_afu *afu = vma->vm_private_data;
113 	unsigned long offset;
114 
115 	if (vmf->pgoff >= (afu->config.global_mmio_size >> PAGE_SHIFT))
116 		return VM_FAULT_SIGBUS;
117 
118 	offset = vmf->pgoff;
119 	offset += (afu->global_mmio_start >> PAGE_SHIFT);
120 	return vmf_insert_pfn(vma, vmf->address, offset);
121 }
122 
123 static const struct vm_operations_struct global_mmio_vmops = {
124 	.fault = global_mmio_fault,
125 };
126 
127 static int global_mmio_mmap(struct file *filp, struct kobject *kobj,
128 			struct bin_attribute *bin_attr,
129 			struct vm_area_struct *vma)
130 {
131 	struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
132 
133 	if ((vma_pages(vma) + vma->vm_pgoff) >
134 		(afu->config.global_mmio_size >> PAGE_SHIFT))
135 		return -EINVAL;
136 
137 	vma->vm_flags |= VM_IO | VM_PFNMAP;
138 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
139 	vma->vm_ops = &global_mmio_vmops;
140 	vma->vm_private_data = afu;
141 	return 0;
142 }
143 
144 int ocxl_sysfs_register_afu(struct ocxl_file_info *info)
145 {
146 	int i, rc;
147 
148 	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
149 		rc = device_create_file(&info->dev, &afu_attrs[i]);
150 		if (rc)
151 			goto err;
152 	}
153 
154 	sysfs_attr_init(&info->attr_global_mmio.attr);
155 	info->attr_global_mmio.attr.name = "global_mmio_area";
156 	info->attr_global_mmio.attr.mode = 0600;
157 	info->attr_global_mmio.size = info->afu->config.global_mmio_size;
158 	info->attr_global_mmio.read = global_mmio_read;
159 	info->attr_global_mmio.mmap = global_mmio_mmap;
160 	rc = device_create_bin_file(&info->dev, &info->attr_global_mmio);
161 	if (rc) {
162 		dev_err(&info->dev, "Unable to create global mmio attr for afu: %d\n", rc);
163 		goto err;
164 	}
165 
166 	return 0;
167 
168 err:
169 	for (i--; i >= 0; i--)
170 		device_remove_file(&info->dev, &afu_attrs[i]);
171 
172 	return rc;
173 }
174 
175 void ocxl_sysfs_unregister_afu(struct ocxl_file_info *info)
176 {
177 	int i;
178 
179 	/*
180 	 * device_remove_bin_file is safe to call if the file is not added as
181 	 * the files are removed by name, and early exit if not found
182 	 */
183 	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
184 		device_remove_file(&info->dev, &afu_attrs[i]);
185 	device_remove_bin_file(&info->dev, &info->attr_global_mmio);
186 }
187