kdebugfs.c

  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/init.h>
  3#include <linux/export.h>
  4#include <linux/debugfs.h>
  5#include <linux/kstrtox.h>
  6#include <asm/loongarch.h>
  7
  8struct dentry *arch_debugfs_dir;
  9EXPORT_SYMBOL(arch_debugfs_dir);
 10
 11static int sfb_state, tso_state;
 12
 13static void set_sfb_state(void *info)
 14{
 15	int val = *(int *)info << CSR_STFILL_SHIFT;
 16
 17	csr_xchg32(val, CSR_STFILL, LOONGARCH_CSR_IMPCTL1);
 18}
 19
 20static ssize_t sfb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 21{
 22	int s, state;
 23	char str[32];
 24
 25	state = (csr_read32(LOONGARCH_CSR_IMPCTL1) & CSR_STFILL) >> CSR_STFILL_SHIFT;
 26
 27	s = snprintf(str, sizeof(str), "Boot State: %x\nCurrent State: %x\n", sfb_state, state);
 28
 29	if (*ppos >= s)
 30		return 0;
 31
 32	s -= *ppos;
 33	s = min_t(u32, s, count);
 34
 35	if (copy_to_user(buf, &str[*ppos], s))
 36		return -EFAULT;
 37
 38	*ppos += s;
 39
 40	return s;
 41}
 42
 43static ssize_t sfb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 44{
 45	int state;
 46
 47	if (kstrtoint_from_user(buf, count, 10, &state))
 48		return -EFAULT;
 49
 50	switch (state) {
 51	case 0: case 1:
 52		on_each_cpu(set_sfb_state, &state, 1);
 53		break;
 54	default:
 55		return -EINVAL;
 56	}
 57
 58	return count;
 59}
 60
 61static const struct file_operations sfb_fops = {
 62	.read = sfb_read,
 63	.write = sfb_write,
 64	.open = simple_open,
 65	.llseek = default_llseek
 66};
 67
 68#define LDSTORDER_NLD_NST        0x0 /* 000 = No Load No Store */
 69#define LDSTORDER_ALD_NST        0x1 /* 001 = All Load No Store */
 70#define LDSTORDER_SLD_NST        0x3 /* 011 = Same Load No Store */
 71#define LDSTORDER_NLD_AST        0x4 /* 100 = No Load All Store */
 72#define LDSTORDER_ALD_AST        0x5 /* 101 = All Load All Store */
 73#define LDSTORDER_SLD_AST        0x7 /* 111 = Same Load All Store */
 74
 75static char *tso_hints[] = {
 76	"No Load No Store",
 77	"All Load No Store",
 78	"Invalid Config",
 79	"Same Load No Store",
 80	"No Load All Store",
 81	"All Load All Store",
 82	"Invalid Config",
 83	"Same Load All Store"
 84};
 85
 86static void set_tso_state(void *info)
 87{
 88	int val = *(int *)info << CSR_LDSTORDER_SHIFT;
 89
 90	csr_xchg32(val, CSR_LDSTORDER_MASK, LOONGARCH_CSR_IMPCTL1);
 91}
 92
 93static ssize_t tso_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 94{
 95	int s, state;
 96	char str[240];
 97
 98	state = (csr_read32(LOONGARCH_CSR_IMPCTL1) & CSR_LDSTORDER_MASK) >> CSR_LDSTORDER_SHIFT;
 99
100	s = snprintf(str, sizeof(str), "Boot State: %d (%s)\n"
101			               "Current State: %d (%s)\n\n"
102				       "Available States:\n"
103				       "0 (%s)\t" "1 (%s)\t" "3 (%s)\n"
104				       "4 (%s)\t" "5 (%s)\t" "7 (%s)\n",
105				       tso_state, tso_hints[tso_state], state, tso_hints[state],
106				       tso_hints[0], tso_hints[1], tso_hints[3], tso_hints[4], tso_hints[5], tso_hints[7]);
107
108	if (*ppos >= s)
109		return 0;
110
111	s -= *ppos;
112	s = min_t(u32, s, count);
113
114	if (copy_to_user(buf, &str[*ppos], s))
115		return -EFAULT;
116
117	*ppos += s;
118
119	return s;
120}
121
122static ssize_t tso_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
123{
124	int state;
125
126	if (kstrtoint_from_user(buf, count, 10, &state))
127		return -EFAULT;
128
129	switch (state) {
130	case 0: case 1: case 3:
131	case 4: case 5: case 7:
132		on_each_cpu(set_tso_state, &state, 1);
133		break;
134	default:
135		return -EINVAL;
136	}
137
138	return count;
139}
140
141static const struct file_operations tso_fops = {
142	.read = tso_read,
143	.write = tso_write,
144	.open = simple_open,
145	.llseek = default_llseek
146};
147
148static int __init arch_kdebugfs_init(void)
149{
150	unsigned int config = read_cpucfg(LOONGARCH_CPUCFG3);
151
152	arch_debugfs_dir = debugfs_create_dir("loongarch", NULL);
153
154	if (config & CPUCFG3_SFB) {
155		debugfs_create_file("sfb_state", S_IRUGO | S_IWUSR,
156			    arch_debugfs_dir, &sfb_state, &sfb_fops);
157		sfb_state = (csr_read32(LOONGARCH_CSR_IMPCTL1) & CSR_STFILL) >> CSR_STFILL_SHIFT;
158	}
159
160	if (config & (CPUCFG3_ALDORDER_CAP | CPUCFG3_ASTORDER_CAP)) {
161		debugfs_create_file("tso_state", S_IRUGO | S_IWUSR,
162			    arch_debugfs_dir, &tso_state, &tso_fops);
163		tso_state = (csr_read32(LOONGARCH_CSR_IMPCTL1) & CSR_LDSTORDER_MASK) >> CSR_LDSTORDER_SHIFT;
164	}
165
166	return 0;
167}
168postcore_initcall(arch_kdebugfs_init);