1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
/*
* Copyright (C) 2016 Imagination Technologies
* Author: Paul Burton <paul.burton@mips.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#define pr_fmt(fmt) "yamon-dt: " fmt
#include <linux/bug.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/libfdt.h>
#include <linux/printk.h>
#include <asm/fw/fw.h>
#include <asm/yamon-dt.h>
#define MAX_MEM_ARRAY_ENTRIES 2
__init int yamon_dt_append_cmdline(void *fdt)
{
int err, chosen_off;
/* find or add chosen node */
chosen_off = fdt_path_offset(fdt, "/chosen");
if (chosen_off == -FDT_ERR_NOTFOUND)
chosen_off = fdt_add_subnode(fdt, 0, "chosen");
if (chosen_off < 0) {
pr_err("Unable to find or add DT chosen node: %d\n",
chosen_off);
return chosen_off;
}
err = fdt_setprop_string(fdt, chosen_off, "bootargs", fw_getcmdline());
if (err) {
pr_err("Unable to set bootargs property: %d\n", err);
return err;
}
return 0;
}
static unsigned int __init gen_fdt_mem_array(
const struct yamon_mem_region *regions,
__be32 *mem_array,
unsigned int max_entries,
unsigned long memsize)
{
const struct yamon_mem_region *mr;
unsigned long size;
unsigned int entries = 0;
for (mr = regions; mr->size && memsize; ++mr) {
if (entries >= max_entries) {
pr_warn("Number of regions exceeds max %u\n",
max_entries);
break;
}
/* How much of the remaining RAM fits in the next region? */
size = min_t(unsigned long, memsize, mr->size);
memsize -= size;
/* Emit a memory region */
*(mem_array++) = cpu_to_be32(mr->start);
*(mem_array++) = cpu_to_be32(size);
++entries;
/* Discard the next mr->discard bytes */
memsize -= min_t(unsigned long, memsize, mr->discard);
}
return entries;
}
__init int yamon_dt_append_memory(void *fdt,
const struct yamon_mem_region *regions)
{
unsigned long phys_memsize = 0, memsize;
__be32 mem_array[2 * MAX_MEM_ARRAY_ENTRIES];
unsigned int mem_entries;
int i, err, mem_off;
char *var, param_name[10], *var_names[] = {
"ememsize", "memsize",
};
/* find memory size from the bootloader environment */
for (i = 0; i < ARRAY_SIZE(var_names); i++) {
var = fw_getenv(var_names[i]);
if (!var)
continue;
err = kstrtoul(var, 0, &phys_memsize);
if (!err)
break;
pr_warn("Failed to read the '%s' env variable '%s'\n",
var_names[i], var);
}
if (!phys_memsize) {
pr_warn("The bootloader didn't provide memsize: defaulting to 32MB\n");
phys_memsize = 32 << 20;
}
/* default to using all available RAM */
memsize = phys_memsize;
/* allow the user to override the usable memory */
for (i = 0; i < ARRAY_SIZE(var_names); i++) {
snprintf(param_name, sizeof(param_name), "%s=", var_names[i]);
var = strstr(arcs_cmdline, param_name);
if (!var)
continue;
memsize = memparse(var + strlen(param_name), NULL);
}
/* if the user says there's more RAM than we thought, believe them */
phys_memsize = max_t(unsigned long, phys_memsize, memsize);
/* find or add a memory node */
mem_off = fdt_path_offset(fdt, "/memory");
if (mem_off == -FDT_ERR_NOTFOUND)
mem_off = fdt_add_subnode(fdt, 0, "memory");
if (mem_off < 0) {
pr_err("Unable to find or add memory DT node: %d\n", mem_off);
return mem_off;
}
err = fdt_setprop_string(fdt, mem_off, "device_type", "memory");
if (err) {
pr_err("Unable to set memory node device_type: %d\n", err);
return err;
}
mem_entries = gen_fdt_mem_array(regions, mem_array,
MAX_MEM_ARRAY_ENTRIES, phys_memsize);
err = fdt_setprop(fdt, mem_off, "reg",
mem_array, mem_entries * 2 * sizeof(mem_array[0]));
if (err) {
pr_err("Unable to set memory regs property: %d\n", err);
return err;
}
mem_entries = gen_fdt_mem_array(regions, mem_array,
MAX_MEM_ARRAY_ENTRIES, memsize);
err = fdt_setprop(fdt, mem_off, "linux,usable-memory",
mem_array, mem_entries * 2 * sizeof(mem_array[0]));
if (err) {
pr_err("Unable to set linux,usable-memory property: %d\n", err);
return err;
}
return 0;
}
__init int yamon_dt_serial_config(void *fdt)
{
const char *yamontty, *mode_var;
char mode_var_name[9], path[20], parity;
unsigned int uart, baud, stop_bits;
bool hw_flow;
int chosen_off, err;
yamontty = fw_getenv("yamontty");
if (!yamontty || !strcmp(yamontty, "tty0")) {
uart = 0;
} else if (!strcmp(yamontty, "tty1")) {
uart = 1;
} else {
pr_warn("yamontty environment variable '%s' invalid\n",
yamontty);
uart = 0;
}
baud = stop_bits = 0;
parity = 0;
hw_flow = false;
snprintf(mode_var_name, sizeof(mode_var_name), "modetty%u", uart);
mode_var = fw_getenv(mode_var_name);
if (mode_var) {
while (mode_var[0] >= '0' && mode_var[0] <= '9') {
baud *= 10;
baud += mode_var[0] - '0';
mode_var++;
}
if (mode_var[0] == ',')
mode_var++;
if (mode_var[0])
parity = mode_var[0];
if (mode_var[0] == ',')
mode_var++;
if (mode_var[0])
stop_bits = mode_var[0] - '0';
if (mode_var[0] == ',')
mode_var++;
if (!strcmp(mode_var, "hw"))
hw_flow = true;
}
if (!baud)
baud = 38400;
if (parity != 'e' && parity != 'n' && parity != 'o')
parity = 'n';
if (stop_bits != 7 && stop_bits != 8)
stop_bits = 8;
WARN_ON(snprintf(path, sizeof(path), "serial%u:%u%c%u%s",
uart, baud, parity, stop_bits,
hw_flow ? "r" : "") >= sizeof(path));
/* find or add chosen node */
chosen_off = fdt_path_offset(fdt, "/chosen");
if (chosen_off == -FDT_ERR_NOTFOUND)
chosen_off = fdt_add_subnode(fdt, 0, "chosen");
if (chosen_off < 0) {
pr_err("Unable to find or add DT chosen node: %d\n",
chosen_off);
return chosen_off;
}
err = fdt_setprop_string(fdt, chosen_off, "stdout-path", path);
if (err) {
pr_err("Unable to set stdout-path property: %d\n", err);
return err;
}
return 0;
}
|
