xref: /openbmc/linux/arch/mips/sibyte/common/cfe.c (revision bbaf1ff0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2000, 2001, 2002, 2003 Broadcom Corporation
4  */
5 
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/linkage.h>
9 #include <linux/mm.h>
10 #include <linux/memblock.h>
11 #include <linux/pm.h>
12 #include <linux/smp.h>
13 
14 #include <asm/bootinfo.h>
15 #include <asm/reboot.h>
16 #include <asm/setup.h>
17 #include <asm/sibyte/board.h>
18 #include <asm/smp-ops.h>
19 
20 #include <asm/fw/cfe/cfe_api.h>
21 #include <asm/fw/cfe/cfe_error.h>
22 
23 /* Max ram addressable in 32-bit segments */
24 #ifdef CONFIG_64BIT
25 #define MAX_RAM_SIZE (~0ULL)
26 #else
27 #ifdef CONFIG_HIGHMEM
28 #ifdef CONFIG_PHYS_ADDR_T_64BIT
29 #define MAX_RAM_SIZE (~0ULL)
30 #else
31 #define MAX_RAM_SIZE (0xffffffffULL)
32 #endif
33 #else
34 #define MAX_RAM_SIZE (0x1fffffffULL)
35 #endif
36 #endif
37 
38 int cfe_cons_handle;
39 
40 #ifdef CONFIG_BLK_DEV_INITRD
41 extern unsigned long initrd_start, initrd_end;
42 #endif
43 
44 static void __noreturn cfe_linux_exit(void *arg)
45 {
46 	int warm = *(int *)arg;
47 
48 	if (smp_processor_id()) {
49 		static int reboot_smp;
50 
51 		/* Don't repeat the process from another CPU */
52 		if (!reboot_smp) {
53 			/* Get CPU 0 to do the cfe_exit */
54 			reboot_smp = 1;
55 			smp_call_function(cfe_linux_exit, arg, 0);
56 		}
57 	} else {
58 		printk("Passing control back to CFE...\n");
59 		cfe_exit(warm, 0);
60 		printk("cfe_exit returned??\n");
61 	}
62 	while (1);
63 }
64 
65 static void __noreturn cfe_linux_restart(char *command)
66 {
67 	static const int zero;
68 
69 	cfe_linux_exit((void *)&zero);
70 }
71 
72 static void __noreturn cfe_linux_halt(void)
73 {
74 	static const int one = 1;
75 
76 	cfe_linux_exit((void *)&one);
77 }
78 
79 static __init void prom_meminit(void)
80 {
81 	u64 addr, size, type; /* regardless of PHYS_ADDR_T_64BIT */
82 	int mem_flags = 0;
83 	unsigned int idx;
84 	int rd_flag;
85 #ifdef CONFIG_BLK_DEV_INITRD
86 	unsigned long initrd_pstart;
87 	unsigned long initrd_pend;
88 
89 	initrd_pstart = CPHYSADDR(initrd_start);
90 	initrd_pend = CPHYSADDR(initrd_end);
91 	if (initrd_start &&
92 	    ((initrd_pstart > MAX_RAM_SIZE)
93 	     || (initrd_pend > MAX_RAM_SIZE))) {
94 		panic("initrd out of addressable memory");
95 	}
96 
97 #endif /* INITRD */
98 
99 	for (idx = 0; cfe_enummem(idx, mem_flags, &addr, &size, &type) != CFE_ERR_NOMORE;
100 	     idx++) {
101 		rd_flag = 0;
102 		if (type == CFE_MI_AVAILABLE) {
103 			/*
104 			 * See if this block contains (any portion of) the
105 			 * ramdisk
106 			 */
107 #ifdef CONFIG_BLK_DEV_INITRD
108 			if (initrd_start) {
109 				if ((initrd_pstart > addr) &&
110 				    (initrd_pstart < (addr + size))) {
111 					memblock_add(addr,
112 						     initrd_pstart - addr);
113 					rd_flag = 1;
114 				}
115 				if ((initrd_pend > addr) &&
116 				    (initrd_pend < (addr + size))) {
117 					memblock_add(initrd_pend,
118 						(addr + size) - initrd_pend);
119 					rd_flag = 1;
120 				}
121 			}
122 #endif
123 			if (!rd_flag) {
124 				if (addr > MAX_RAM_SIZE)
125 					continue;
126 				if (addr+size > MAX_RAM_SIZE)
127 					size = MAX_RAM_SIZE - (addr+size) + 1;
128 				/*
129 				 * memcpy/__copy_user prefetch, which
130 				 * will cause a bus error for
131 				 * KSEG/KUSEG addrs not backed by RAM.
132 				 * Hence, reserve some padding for the
133 				 * prefetch distance.
134 				 */
135 				if (size > 512)
136 					size -= 512;
137 				memblock_add(addr, size);
138 			}
139 		}
140 	}
141 #ifdef CONFIG_BLK_DEV_INITRD
142 	if (initrd_start) {
143 		memblock_add(initrd_pstart, initrd_pend - initrd_pstart);
144 		memblock_reserve(initrd_pstart, initrd_pend - initrd_pstart);
145 	}
146 #endif
147 }
148 
149 #ifdef CONFIG_BLK_DEV_INITRD
150 static int __init initrd_setup(char *str)
151 {
152 	char rdarg[64];
153 	int idx;
154 	char *tmp, *endptr;
155 	unsigned long initrd_size;
156 
157 	/* Make a copy of the initrd argument so we can smash it up here */
158 	for (idx = 0; idx < sizeof(rdarg)-1; idx++) {
159 		if (!str[idx] || (str[idx] == ' ')) break;
160 		rdarg[idx] = str[idx];
161 	}
162 
163 	rdarg[idx] = 0;
164 	str = rdarg;
165 
166 	/*
167 	 *Initrd location comes in the form "<hex size of ramdisk in bytes>@<location in memory>"
168 	 *  e.g. initrd=3abfd@80010000.	 This is set up by the loader.
169 	 */
170 	for (tmp = str; *tmp != '@'; tmp++) {
171 		if (!*tmp) {
172 			goto fail;
173 		}
174 	}
175 	*tmp = 0;
176 	tmp++;
177 	if (!*tmp) {
178 		goto fail;
179 	}
180 	initrd_size = simple_strtoul(str, &endptr, 16);
181 	if (*endptr) {
182 		*(tmp-1) = '@';
183 		goto fail;
184 	}
185 	*(tmp-1) = '@';
186 	initrd_start = simple_strtoul(tmp, &endptr, 16);
187 	if (*endptr) {
188 		goto fail;
189 	}
190 	initrd_end = initrd_start + initrd_size;
191 	printk("Found initrd of %lx@%lx\n", initrd_size, initrd_start);
192 	return 1;
193  fail:
194 	printk("Bad initrd argument.  Disabling initrd\n");
195 	initrd_start = 0;
196 	initrd_end = 0;
197 	return 1;
198 }
199 
200 #endif
201 
202 extern const struct plat_smp_ops sb_smp_ops;
203 extern const struct plat_smp_ops bcm1480_smp_ops;
204 
205 /*
206  * prom_init is called just after the cpu type is determined, from setup_arch()
207  */
208 void __init prom_init(void)
209 {
210 	uint64_t cfe_ept, cfe_handle;
211 	unsigned int cfe_eptseal;
212 	int argc = fw_arg0;
213 	char **envp = (char **) fw_arg2;
214 	int *prom_vec = (int *) fw_arg3;
215 
216 	_machine_restart   = cfe_linux_restart;
217 	_machine_halt	   = cfe_linux_halt;
218 	pm_power_off = cfe_linux_halt;
219 
220 	/*
221 	 * Check if a loader was used; if NOT, the 4 arguments are
222 	 * what CFE gives us (handle, 0, EPT and EPTSEAL)
223 	 */
224 	if (argc < 0) {
225 		cfe_handle = (uint64_t)(long)argc;
226 		cfe_ept = (long)envp;
227 		cfe_eptseal = (uint32_t)(unsigned long)prom_vec;
228 	} else {
229 		if ((int32_t)(long)prom_vec < 0) {
230 			/*
231 			 * Old loader; all it gives us is the handle,
232 			 * so use the "known" entrypoint and assume
233 			 * the seal.
234 			 */
235 			cfe_handle = (uint64_t)(long)prom_vec;
236 			cfe_ept = (uint64_t)((int32_t)0x9fc00500);
237 			cfe_eptseal = CFE_EPTSEAL;
238 		} else {
239 			/*
240 			 * Newer loaders bundle the handle/ept/eptseal
241 			 * Note: prom_vec is in the loader's useg
242 			 * which is still alive in the TLB.
243 			 */
244 			cfe_handle = (uint64_t)((int32_t *)prom_vec)[0];
245 			cfe_ept = (uint64_t)((int32_t *)prom_vec)[2];
246 			cfe_eptseal = (unsigned int)((uint32_t *)prom_vec)[3];
247 		}
248 	}
249 	if (cfe_eptseal != CFE_EPTSEAL) {
250 		/* too early for panic to do any good */
251 		printk("CFE's entrypoint seal doesn't match. Spinning.");
252 		while (1) ;
253 	}
254 	cfe_init(cfe_handle, cfe_ept);
255 	/*
256 	 * Get the handle for (at least) prom_putchar, possibly for
257 	 * boot console
258 	 */
259 	cfe_cons_handle = cfe_getstdhandle(CFE_STDHANDLE_CONSOLE);
260 	if (cfe_getenv("LINUX_CMDLINE", arcs_cmdline, COMMAND_LINE_SIZE) < 0) {
261 		if (argc >= 0) {
262 			/* The loader should have set the command line */
263 			/* too early for panic to do any good */
264 			printk("LINUX_CMDLINE not defined in cfe.");
265 			while (1) ;
266 		}
267 	}
268 
269 #ifdef CONFIG_BLK_DEV_INITRD
270 	{
271 		char *ptr;
272 		/* Need to find out early whether we've got an initrd.	So scan
273 		   the list looking now */
274 		for (ptr = arcs_cmdline; *ptr; ptr++) {
275 			while (*ptr == ' ') {
276 				ptr++;
277 			}
278 			if (!strncmp(ptr, "initrd=", 7)) {
279 				initrd_setup(ptr+7);
280 				break;
281 			} else {
282 				while (*ptr && (*ptr != ' ')) {
283 					ptr++;
284 				}
285 			}
286 		}
287 	}
288 #endif /* CONFIG_BLK_DEV_INITRD */
289 
290 	/* Not sure this is needed, but it's the safe way. */
291 	arcs_cmdline[COMMAND_LINE_SIZE-1] = 0;
292 
293 	prom_meminit();
294 
295 #if defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
296 	register_smp_ops(&sb_smp_ops);
297 #endif
298 #ifdef CONFIG_SIBYTE_BCM1x80
299 	register_smp_ops(&bcm1480_smp_ops);
300 #endif
301 }
302 
303 void prom_putchar(char c)
304 {
305 	int ret;
306 
307 	while ((ret = cfe_write(cfe_cons_handle, &c, 1)) == 0)
308 		;
309 }
310