12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
2571b7e69SPaul Burton /*
3571b7e69SPaul Burton * Copyright (C) 2016 Imagination Technologies
4fb615d61SPaul Burton * Author: Paul Burton <paul.burton@mips.com>
5571b7e69SPaul Burton */
6571b7e69SPaul Burton
7571b7e69SPaul Burton #define pr_fmt(fmt) "yamon-dt: " fmt
8571b7e69SPaul Burton
9571b7e69SPaul Burton #include <linux/bug.h>
10571b7e69SPaul Burton #include <linux/errno.h>
11571b7e69SPaul Burton #include <linux/kernel.h>
12571b7e69SPaul Burton #include <linux/libfdt.h>
13571b7e69SPaul Burton #include <linux/printk.h>
14571b7e69SPaul Burton
15571b7e69SPaul Burton #include <asm/fw/fw.h>
16f41d2430SPaul Burton #include <asm/yamon-dt.h>
17f41d2430SPaul Burton
18f41d2430SPaul Burton #define MAX_MEM_ARRAY_ENTRIES 2
19571b7e69SPaul Burton
yamon_dt_append_cmdline(void * fdt)20571b7e69SPaul Burton __init int yamon_dt_append_cmdline(void *fdt)
21571b7e69SPaul Burton {
22571b7e69SPaul Burton int err, chosen_off;
23571b7e69SPaul Burton
24571b7e69SPaul Burton /* find or add chosen node */
25571b7e69SPaul Burton chosen_off = fdt_path_offset(fdt, "/chosen");
26571b7e69SPaul Burton if (chosen_off == -FDT_ERR_NOTFOUND)
27571b7e69SPaul Burton chosen_off = fdt_add_subnode(fdt, 0, "chosen");
28571b7e69SPaul Burton if (chosen_off < 0) {
29571b7e69SPaul Burton pr_err("Unable to find or add DT chosen node: %d\n",
30571b7e69SPaul Burton chosen_off);
31571b7e69SPaul Burton return chosen_off;
32571b7e69SPaul Burton }
33571b7e69SPaul Burton
34571b7e69SPaul Burton err = fdt_setprop_string(fdt, chosen_off, "bootargs", fw_getcmdline());
35571b7e69SPaul Burton if (err) {
36571b7e69SPaul Burton pr_err("Unable to set bootargs property: %d\n", err);
37571b7e69SPaul Burton return err;
38571b7e69SPaul Burton }
39571b7e69SPaul Burton
40571b7e69SPaul Burton return 0;
41571b7e69SPaul Burton }
42571b7e69SPaul Burton
gen_fdt_mem_array(const struct yamon_mem_region * regions,__be32 * mem_array,unsigned int max_entries,unsigned long memsize)43f41d2430SPaul Burton static unsigned int __init gen_fdt_mem_array(
44f41d2430SPaul Burton const struct yamon_mem_region *regions,
45f41d2430SPaul Burton __be32 *mem_array,
46f41d2430SPaul Burton unsigned int max_entries,
47f41d2430SPaul Burton unsigned long memsize)
48f41d2430SPaul Burton {
49f41d2430SPaul Burton const struct yamon_mem_region *mr;
50f41d2430SPaul Burton unsigned long size;
51f41d2430SPaul Burton unsigned int entries = 0;
52f41d2430SPaul Burton
53f41d2430SPaul Burton for (mr = regions; mr->size && memsize; ++mr) {
54f41d2430SPaul Burton if (entries >= max_entries) {
55f41d2430SPaul Burton pr_warn("Number of regions exceeds max %u\n",
56f41d2430SPaul Burton max_entries);
57f41d2430SPaul Burton break;
58f41d2430SPaul Burton }
59f41d2430SPaul Burton
60f41d2430SPaul Burton /* How much of the remaining RAM fits in the next region? */
61f41d2430SPaul Burton size = min_t(unsigned long, memsize, mr->size);
62f41d2430SPaul Burton memsize -= size;
63f41d2430SPaul Burton
64f41d2430SPaul Burton /* Emit a memory region */
65f41d2430SPaul Burton *(mem_array++) = cpu_to_be32(mr->start);
66f41d2430SPaul Burton *(mem_array++) = cpu_to_be32(size);
67f41d2430SPaul Burton ++entries;
68f41d2430SPaul Burton
69f41d2430SPaul Burton /* Discard the next mr->discard bytes */
70f41d2430SPaul Burton memsize -= min_t(unsigned long, memsize, mr->discard);
71f41d2430SPaul Burton }
72f41d2430SPaul Burton return entries;
73f41d2430SPaul Burton }
74f41d2430SPaul Burton
yamon_dt_append_memory(void * fdt,const struct yamon_mem_region * regions)75f41d2430SPaul Burton __init int yamon_dt_append_memory(void *fdt,
76f41d2430SPaul Burton const struct yamon_mem_region *regions)
77571b7e69SPaul Burton {
78*255e51daSColin Ian King unsigned long phys_memsize = 0, memsize;
79f41d2430SPaul Burton __be32 mem_array[2 * MAX_MEM_ARRAY_ENTRIES];
80f41d2430SPaul Burton unsigned int mem_entries;
81f41d2430SPaul Burton int i, err, mem_off;
82f41d2430SPaul Burton char *var, param_name[10], *var_names[] = {
83f41d2430SPaul Burton "ememsize", "memsize",
84f41d2430SPaul Burton };
85571b7e69SPaul Burton
86571b7e69SPaul Burton /* find memory size from the bootloader environment */
87f41d2430SPaul Burton for (i = 0; i < ARRAY_SIZE(var_names); i++) {
88f41d2430SPaul Burton var = fw_getenv(var_names[i]);
89f41d2430SPaul Burton if (!var)
90f41d2430SPaul Burton continue;
91f41d2430SPaul Burton
92571b7e69SPaul Burton err = kstrtoul(var, 0, &phys_memsize);
93f41d2430SPaul Burton if (!err)
94f41d2430SPaul Burton break;
95f41d2430SPaul Burton
96f41d2430SPaul Burton pr_warn("Failed to read the '%s' env variable '%s'\n",
97f41d2430SPaul Burton var_names[i], var);
98571b7e69SPaul Burton }
99f41d2430SPaul Burton
100f41d2430SPaul Burton if (!phys_memsize) {
101571b7e69SPaul Burton pr_warn("The bootloader didn't provide memsize: defaulting to 32MB\n");
102571b7e69SPaul Burton phys_memsize = 32 << 20;
103571b7e69SPaul Burton }
104571b7e69SPaul Burton
105571b7e69SPaul Burton /* default to using all available RAM */
106571b7e69SPaul Burton memsize = phys_memsize;
107571b7e69SPaul Burton
108571b7e69SPaul Burton /* allow the user to override the usable memory */
109f41d2430SPaul Burton for (i = 0; i < ARRAY_SIZE(var_names); i++) {
110f41d2430SPaul Burton snprintf(param_name, sizeof(param_name), "%s=", var_names[i]);
111f41d2430SPaul Burton var = strstr(arcs_cmdline, param_name);
112f41d2430SPaul Burton if (!var)
113f41d2430SPaul Burton continue;
114f41d2430SPaul Burton
115f41d2430SPaul Burton memsize = memparse(var + strlen(param_name), NULL);
116f41d2430SPaul Burton }
117571b7e69SPaul Burton
118571b7e69SPaul Burton /* if the user says there's more RAM than we thought, believe them */
119571b7e69SPaul Burton phys_memsize = max_t(unsigned long, phys_memsize, memsize);
120571b7e69SPaul Burton
121571b7e69SPaul Burton /* find or add a memory node */
122571b7e69SPaul Burton mem_off = fdt_path_offset(fdt, "/memory");
123571b7e69SPaul Burton if (mem_off == -FDT_ERR_NOTFOUND)
124571b7e69SPaul Burton mem_off = fdt_add_subnode(fdt, 0, "memory");
125571b7e69SPaul Burton if (mem_off < 0) {
126571b7e69SPaul Burton pr_err("Unable to find or add memory DT node: %d\n", mem_off);
127571b7e69SPaul Burton return mem_off;
128571b7e69SPaul Burton }
129571b7e69SPaul Burton
130571b7e69SPaul Burton err = fdt_setprop_string(fdt, mem_off, "device_type", "memory");
131571b7e69SPaul Burton if (err) {
132571b7e69SPaul Burton pr_err("Unable to set memory node device_type: %d\n", err);
133571b7e69SPaul Burton return err;
134571b7e69SPaul Burton }
135571b7e69SPaul Burton
136f41d2430SPaul Burton mem_entries = gen_fdt_mem_array(regions, mem_array,
137f41d2430SPaul Burton MAX_MEM_ARRAY_ENTRIES, phys_memsize);
138f41d2430SPaul Burton err = fdt_setprop(fdt, mem_off, "reg",
139f41d2430SPaul Burton mem_array, mem_entries * 2 * sizeof(mem_array[0]));
140571b7e69SPaul Burton if (err) {
141571b7e69SPaul Burton pr_err("Unable to set memory regs property: %d\n", err);
142571b7e69SPaul Burton return err;
143571b7e69SPaul Burton }
144571b7e69SPaul Burton
145f41d2430SPaul Burton mem_entries = gen_fdt_mem_array(regions, mem_array,
146f41d2430SPaul Burton MAX_MEM_ARRAY_ENTRIES, memsize);
147571b7e69SPaul Burton err = fdt_setprop(fdt, mem_off, "linux,usable-memory",
148f41d2430SPaul Burton mem_array, mem_entries * 2 * sizeof(mem_array[0]));
149571b7e69SPaul Burton if (err) {
150571b7e69SPaul Burton pr_err("Unable to set linux,usable-memory property: %d\n", err);
151571b7e69SPaul Burton return err;
152571b7e69SPaul Burton }
153571b7e69SPaul Burton
154571b7e69SPaul Burton return 0;
155571b7e69SPaul Burton }
156571b7e69SPaul Burton
yamon_dt_serial_config(void * fdt)157571b7e69SPaul Burton __init int yamon_dt_serial_config(void *fdt)
158571b7e69SPaul Burton {
159571b7e69SPaul Burton const char *yamontty, *mode_var;
160c3d62fc6SPaul Burton char mode_var_name[9], path[20], parity;
161571b7e69SPaul Burton unsigned int uart, baud, stop_bits;
162571b7e69SPaul Burton bool hw_flow;
163571b7e69SPaul Burton int chosen_off, err;
164571b7e69SPaul Burton
165571b7e69SPaul Burton yamontty = fw_getenv("yamontty");
166571b7e69SPaul Burton if (!yamontty || !strcmp(yamontty, "tty0")) {
167571b7e69SPaul Burton uart = 0;
168571b7e69SPaul Burton } else if (!strcmp(yamontty, "tty1")) {
169571b7e69SPaul Burton uart = 1;
170571b7e69SPaul Burton } else {
171571b7e69SPaul Burton pr_warn("yamontty environment variable '%s' invalid\n",
172571b7e69SPaul Burton yamontty);
173571b7e69SPaul Burton uart = 0;
174571b7e69SPaul Burton }
175571b7e69SPaul Burton
176571b7e69SPaul Burton baud = stop_bits = 0;
177571b7e69SPaul Burton parity = 0;
178571b7e69SPaul Burton hw_flow = false;
179571b7e69SPaul Burton
180571b7e69SPaul Burton snprintf(mode_var_name, sizeof(mode_var_name), "modetty%u", uart);
181571b7e69SPaul Burton mode_var = fw_getenv(mode_var_name);
182571b7e69SPaul Burton if (mode_var) {
183571b7e69SPaul Burton while (mode_var[0] >= '0' && mode_var[0] <= '9') {
184571b7e69SPaul Burton baud *= 10;
185571b7e69SPaul Burton baud += mode_var[0] - '0';
186571b7e69SPaul Burton mode_var++;
187571b7e69SPaul Burton }
188571b7e69SPaul Burton if (mode_var[0] == ',')
189571b7e69SPaul Burton mode_var++;
190571b7e69SPaul Burton if (mode_var[0])
191571b7e69SPaul Burton parity = mode_var[0];
192571b7e69SPaul Burton if (mode_var[0] == ',')
193571b7e69SPaul Burton mode_var++;
194571b7e69SPaul Burton if (mode_var[0])
195571b7e69SPaul Burton stop_bits = mode_var[0] - '0';
196571b7e69SPaul Burton if (mode_var[0] == ',')
197571b7e69SPaul Burton mode_var++;
198571b7e69SPaul Burton if (!strcmp(mode_var, "hw"))
199571b7e69SPaul Burton hw_flow = true;
200571b7e69SPaul Burton }
201571b7e69SPaul Burton
202571b7e69SPaul Burton if (!baud)
203571b7e69SPaul Burton baud = 38400;
204571b7e69SPaul Burton
205571b7e69SPaul Burton if (parity != 'e' && parity != 'n' && parity != 'o')
206571b7e69SPaul Burton parity = 'n';
207571b7e69SPaul Burton
208571b7e69SPaul Burton if (stop_bits != 7 && stop_bits != 8)
209571b7e69SPaul Burton stop_bits = 8;
210571b7e69SPaul Burton
211c3d62fc6SPaul Burton WARN_ON(snprintf(path, sizeof(path), "serial%u:%u%c%u%s",
212571b7e69SPaul Burton uart, baud, parity, stop_bits,
213571b7e69SPaul Burton hw_flow ? "r" : "") >= sizeof(path));
214571b7e69SPaul Burton
215571b7e69SPaul Burton /* find or add chosen node */
216571b7e69SPaul Burton chosen_off = fdt_path_offset(fdt, "/chosen");
217571b7e69SPaul Burton if (chosen_off == -FDT_ERR_NOTFOUND)
218571b7e69SPaul Burton chosen_off = fdt_add_subnode(fdt, 0, "chosen");
219571b7e69SPaul Burton if (chosen_off < 0) {
220571b7e69SPaul Burton pr_err("Unable to find or add DT chosen node: %d\n",
221571b7e69SPaul Burton chosen_off);
222571b7e69SPaul Burton return chosen_off;
223571b7e69SPaul Burton }
224571b7e69SPaul Burton
225571b7e69SPaul Burton err = fdt_setprop_string(fdt, chosen_off, "stdout-path", path);
226571b7e69SPaul Burton if (err) {
227571b7e69SPaul Burton pr_err("Unable to set stdout-path property: %d\n", err);
228571b7e69SPaul Burton return err;
229571b7e69SPaul Burton }
230571b7e69SPaul Burton
231571b7e69SPaul Burton return 0;
232571b7e69SPaul Burton }
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