xref: /openbmc/linux/drivers/misc/ocxl/sysfs.c (revision 9be08a27)
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 ssize_t global_mmio_size_show(struct device *device,
7 				struct device_attribute *attr,
8 				char *buf)
9 {
10 	struct ocxl_afu *afu = to_ocxl_afu(device);
11 
12 	return scnprintf(buf, PAGE_SIZE, "%d\n",
13 			afu->config.global_mmio_size);
14 }
15 
16 static ssize_t pp_mmio_size_show(struct device *device,
17 				struct device_attribute *attr,
18 				char *buf)
19 {
20 	struct ocxl_afu *afu = to_ocxl_afu(device);
21 
22 	return scnprintf(buf, PAGE_SIZE, "%d\n",
23 			afu->config.pp_mmio_stride);
24 }
25 
26 static ssize_t afu_version_show(struct device *device,
27 				struct device_attribute *attr,
28 				char *buf)
29 {
30 	struct ocxl_afu *afu = to_ocxl_afu(device);
31 
32 	return scnprintf(buf, PAGE_SIZE, "%hhu:%hhu\n",
33 			afu->config.version_major,
34 			afu->config.version_minor);
35 }
36 
37 static ssize_t contexts_show(struct device *device,
38 		struct device_attribute *attr,
39 		char *buf)
40 {
41 	struct ocxl_afu *afu = to_ocxl_afu(device);
42 
43 	return scnprintf(buf, PAGE_SIZE, "%d/%d\n",
44 			afu->pasid_count, afu->pasid_max);
45 }
46 
47 static struct device_attribute afu_attrs[] = {
48 	__ATTR_RO(global_mmio_size),
49 	__ATTR_RO(pp_mmio_size),
50 	__ATTR_RO(afu_version),
51 	__ATTR_RO(contexts),
52 };
53 
54 static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
55 				struct bin_attribute *bin_attr, char *buf,
56 				loff_t off, size_t count)
57 {
58 	struct ocxl_afu *afu = to_ocxl_afu(kobj_to_dev(kobj));
59 
60 	if (count == 0 || off < 0 ||
61 		off >= afu->config.global_mmio_size)
62 		return 0;
63 	memcpy_fromio(buf, afu->global_mmio_ptr + off, count);
64 	return count;
65 }
66 
67 static vm_fault_t global_mmio_fault(struct vm_fault *vmf)
68 {
69 	struct vm_area_struct *vma = vmf->vma;
70 	struct ocxl_afu *afu = vma->vm_private_data;
71 	unsigned long offset;
72 
73 	if (vmf->pgoff >= (afu->config.global_mmio_size >> PAGE_SHIFT))
74 		return VM_FAULT_SIGBUS;
75 
76 	offset = vmf->pgoff;
77 	offset += (afu->global_mmio_start >> PAGE_SHIFT);
78 	return vmf_insert_pfn(vma, vmf->address, offset);
79 }
80 
81 static const struct vm_operations_struct global_mmio_vmops = {
82 	.fault = global_mmio_fault,
83 };
84 
85 static int global_mmio_mmap(struct file *filp, struct kobject *kobj,
86 			struct bin_attribute *bin_attr,
87 			struct vm_area_struct *vma)
88 {
89 	struct ocxl_afu *afu = to_ocxl_afu(kobj_to_dev(kobj));
90 
91 	if ((vma_pages(vma) + vma->vm_pgoff) >
92 		(afu->config.global_mmio_size >> PAGE_SHIFT))
93 		return -EINVAL;
94 
95 	vma->vm_flags |= VM_IO | VM_PFNMAP;
96 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
97 	vma->vm_ops = &global_mmio_vmops;
98 	vma->vm_private_data = afu;
99 	return 0;
100 }
101 
102 int ocxl_sysfs_add_afu(struct ocxl_afu *afu)
103 {
104 	int i, rc;
105 
106 	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
107 		rc = device_create_file(&afu->dev, &afu_attrs[i]);
108 		if (rc)
109 			goto err;
110 	}
111 
112 	sysfs_attr_init(&afu->attr_global_mmio.attr);
113 	afu->attr_global_mmio.attr.name = "global_mmio_area";
114 	afu->attr_global_mmio.attr.mode = 0600;
115 	afu->attr_global_mmio.size = afu->config.global_mmio_size;
116 	afu->attr_global_mmio.read = global_mmio_read;
117 	afu->attr_global_mmio.mmap = global_mmio_mmap;
118 	rc = device_create_bin_file(&afu->dev, &afu->attr_global_mmio);
119 	if (rc) {
120 		dev_err(&afu->dev,
121 			"Unable to create global mmio attr for afu: %d\n",
122 			rc);
123 		goto err;
124 	}
125 
126 	return 0;
127 
128 err:
129 	for (i--; i >= 0; i--)
130 		device_remove_file(&afu->dev, &afu_attrs[i]);
131 	return rc;
132 }
133 
134 void ocxl_sysfs_remove_afu(struct ocxl_afu *afu)
135 {
136 	int i;
137 
138 	for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
139 		device_remove_file(&afu->dev, &afu_attrs[i]);
140 	device_remove_bin_file(&afu->dev, &afu->attr_global_mmio);
141 }
142