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1 /*
2 * Copyright IBM Corp. 2012,2015
3 *
4 * Author(s):
5 * Jan Glauber <jang@linux.vnet.ibm.com>
6 */
7
8 #define KMSG_COMPONENT "zpci"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10
11 #include <linux/kernel.h>
12 #include <linux/seq_file.h>
13 #include <linux/debugfs.h>
14 #include <linux/export.h>
15 #include <linux/pci.h>
16 #include <asm/debug.h>
17
18 #include <asm/pci_dma.h>
19
20 static struct dentry *debugfs_root;
21 debug_info_t *pci_debug_msg_id;
22 EXPORT_SYMBOL_GPL(pci_debug_msg_id);
23 debug_info_t *pci_debug_err_id;
24 EXPORT_SYMBOL_GPL(pci_debug_err_id);
25
26 static char *pci_common_names[] = {
27 "Load operations",
28 "Store operations",
29 "Store block operations",
30 "Refresh operations",
31 };
32
33 static char *pci_fmt0_names[] = {
34 "DMA read bytes",
35 "DMA write bytes",
36 };
37
38 static char *pci_fmt1_names[] = {
39 "Received bytes",
40 "Received packets",
41 "Transmitted bytes",
42 "Transmitted packets",
43 };
44
45 static char *pci_fmt2_names[] = {
46 "Consumed work units",
47 "Maximum work units",
48 };
49
50 static char *pci_sw_names[] = {
51 "Allocated pages",
52 "Mapped pages",
53 "Unmapped pages",
54 };
55
56 static void pci_fmb_show(struct seq_file *m, char *name[], int length,
57 u64 *data)
58 {
59 int i;
60
61 for (i = 0; i < length; i++, data++)
62 seq_printf(m, "%26s:\t%llu\n", name[i], *data);
63 }
64
65 static void pci_sw_counter_show(struct seq_file *m)
66 {
67 struct zpci_dev *zdev = m->private;
68 atomic64_t *counter = &zdev->allocated_pages;
69 int i;
70
71 for (i = 0; i < ARRAY_SIZE(pci_sw_names); i++, counter++)
72 seq_printf(m, "%26s:\t%lu\n", pci_sw_names[i],
73 atomic64_read(counter));
74 }
75
76 static int pci_perf_show(struct seq_file *m, void *v)
77 {
78 struct zpci_dev *zdev = m->private;
79
80 if (!zdev)
81 return 0;
82
83 mutex_lock(&zdev->lock);
84 if (!zdev->fmb) {
85 mutex_unlock(&zdev->lock);
86 seq_puts(m, "FMB statistics disabled\n");
87 return 0;
88 }
89
90 /* header */
91 seq_printf(m, "FMB @ %p\n", zdev->fmb);
92 seq_printf(m, "Update interval: %u ms\n", zdev->fmb_update);
93 seq_printf(m, "Samples: %u\n", zdev->fmb->samples);
94 seq_printf(m, "Last update TOD: %Lx\n", zdev->fmb->last_update);
95
96 pci_fmb_show(m, pci_common_names, ARRAY_SIZE(pci_common_names),
97 &zdev->fmb->ld_ops);
98
99 switch (zdev->fmb->format) {
100 case 0:
101 if (!(zdev->fmb->fmt_ind & ZPCI_FMB_DMA_COUNTER_VALID))
102 break;
103 pci_fmb_show(m, pci_fmt0_names, ARRAY_SIZE(pci_fmt0_names),
104 &zdev->fmb->fmt0.dma_rbytes);
105 break;
106 case 1:
107 pci_fmb_show(m, pci_fmt1_names, ARRAY_SIZE(pci_fmt1_names),
108 &zdev->fmb->fmt1.rx_bytes);
109 break;
110 case 2:
111 pci_fmb_show(m, pci_fmt2_names, ARRAY_SIZE(pci_fmt2_names),
112 &zdev->fmb->fmt2.consumed_work_units);
113 break;
114 default:
115 seq_puts(m, "Unknown format\n");
116 }
117
118 pci_sw_counter_show(m);
119 mutex_unlock(&zdev->lock);
120 return 0;
121 }
122
123 static ssize_t pci_perf_seq_write(struct file *file, const char __user *ubuf,
124 size_t count, loff_t *off)
125 {
126 struct zpci_dev *zdev = ((struct seq_file *) file->private_data)->private;
127 unsigned long val;
128 int rc;
129
130 if (!zdev)
131 return 0;
132
133 rc = kstrtoul_from_user(ubuf, count, 10, &val);
134 if (rc)
135 return rc;
136
137 mutex_lock(&zdev->lock);
138 switch (val) {
139 case 0:
140 rc = zpci_fmb_disable_device(zdev);
141 break;
142 case 1:
143 rc = zpci_fmb_enable_device(zdev);
144 break;
145 }
146 mutex_unlock(&zdev->lock);
147 return rc ? rc : count;
148 }
149
150 static int pci_perf_seq_open(struct inode *inode, struct file *filp)
151 {
152 return single_open(filp, pci_perf_show,
153 file_inode(filp)->i_private);
154 }
155
156 static const struct file_operations debugfs_pci_perf_fops = {
157 .open = pci_perf_seq_open,
158 .read = seq_read,
159 .write = pci_perf_seq_write,
160 .llseek = seq_lseek,
161 .release = single_release,
162 };
163
164 void zpci_debug_init_device(struct zpci_dev *zdev, const char *name)
165 {
166 zdev->debugfs_dev = debugfs_create_dir(name, debugfs_root);
167 if (IS_ERR(zdev->debugfs_dev))
168 zdev->debugfs_dev = NULL;
169
170 zdev->debugfs_perf = debugfs_create_file("statistics",
171 S_IFREG | S_IRUGO | S_IWUSR,
172 zdev->debugfs_dev, zdev,
173 &debugfs_pci_perf_fops);
174 if (IS_ERR(zdev->debugfs_perf))
175 zdev->debugfs_perf = NULL;
176 }
177
178 void zpci_debug_exit_device(struct zpci_dev *zdev)
179 {
180 debugfs_remove(zdev->debugfs_perf);
181 debugfs_remove(zdev->debugfs_dev);
182 }
183
184 int __init zpci_debug_init(void)
185 {
186 /* event trace buffer */
187 pci_debug_msg_id = debug_register("pci_msg", 8, 1, 8 * sizeof(long));
188 if (!pci_debug_msg_id)
189 return -EINVAL;
190 debug_register_view(pci_debug_msg_id, &debug_sprintf_view);
191 debug_set_level(pci_debug_msg_id, 3);
192
193 /* error log */
194 pci_debug_err_id = debug_register("pci_error", 2, 1, 16);
195 if (!pci_debug_err_id)
196 return -EINVAL;
197 debug_register_view(pci_debug_err_id, &debug_hex_ascii_view);
198 debug_set_level(pci_debug_err_id, 6);
199
200 debugfs_root = debugfs_create_dir("pci", NULL);
201 return 0;
202 }
203
204 void zpci_debug_exit(void)
205 {
206 debug_unregister(pci_debug_msg_id);
207 debug_unregister(pci_debug_err_id);
208 debugfs_remove(debugfs_root);
209 }