xref: /openbmc/linux/arch/mips/sibyte/common/cfe.c (revision 0a94608f)
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 #define SIBYTE_MAX_MEM_REGIONS 8
39 phys_addr_t board_mem_region_addrs[SIBYTE_MAX_MEM_REGIONS];
40 phys_addr_t board_mem_region_sizes[SIBYTE_MAX_MEM_REGIONS];
41 unsigned int board_mem_region_count;
42 
43 int cfe_cons_handle;
44 
45 #ifdef CONFIG_BLK_DEV_INITRD
46 extern unsigned long initrd_start, initrd_end;
47 #endif
48 
49 static void __noreturn cfe_linux_exit(void *arg)
50 {
51 	int warm = *(int *)arg;
52 
53 	if (smp_processor_id()) {
54 		static int reboot_smp;
55 
56 		/* Don't repeat the process from another CPU */
57 		if (!reboot_smp) {
58 			/* Get CPU 0 to do the cfe_exit */
59 			reboot_smp = 1;
60 			smp_call_function(cfe_linux_exit, arg, 0);
61 		}
62 	} else {
63 		printk("Passing control back to CFE...\n");
64 		cfe_exit(warm, 0);
65 		printk("cfe_exit returned??\n");
66 	}
67 	while (1);
68 }
69 
70 static void __noreturn cfe_linux_restart(char *command)
71 {
72 	static const int zero;
73 
74 	cfe_linux_exit((void *)&zero);
75 }
76 
77 static void __noreturn cfe_linux_halt(void)
78 {
79 	static const int one = 1;
80 
81 	cfe_linux_exit((void *)&one);
82 }
83 
84 static __init void prom_meminit(void)
85 {
86 	u64 addr, size, type; /* regardless of PHYS_ADDR_T_64BIT */
87 	int mem_flags = 0;
88 	unsigned int idx;
89 	int rd_flag;
90 #ifdef CONFIG_BLK_DEV_INITRD
91 	unsigned long initrd_pstart;
92 	unsigned long initrd_pend;
93 
94 	initrd_pstart = CPHYSADDR(initrd_start);
95 	initrd_pend = CPHYSADDR(initrd_end);
96 	if (initrd_start &&
97 	    ((initrd_pstart > MAX_RAM_SIZE)
98 	     || (initrd_pend > MAX_RAM_SIZE))) {
99 		panic("initrd out of addressable memory");
100 	}
101 
102 #endif /* INITRD */
103 
104 	for (idx = 0; cfe_enummem(idx, mem_flags, &addr, &size, &type) != CFE_ERR_NOMORE;
105 	     idx++) {
106 		rd_flag = 0;
107 		if (type == CFE_MI_AVAILABLE) {
108 			/*
109 			 * See if this block contains (any portion of) the
110 			 * ramdisk
111 			 */
112 #ifdef CONFIG_BLK_DEV_INITRD
113 			if (initrd_start) {
114 				if ((initrd_pstart > addr) &&
115 				    (initrd_pstart < (addr + size))) {
116 					memblock_add(addr,
117 						     initrd_pstart - addr);
118 					rd_flag = 1;
119 				}
120 				if ((initrd_pend > addr) &&
121 				    (initrd_pend < (addr + size))) {
122 					memblock_add(initrd_pend,
123 						(addr + size) - initrd_pend);
124 					rd_flag = 1;
125 				}
126 			}
127 #endif
128 			if (!rd_flag) {
129 				if (addr > MAX_RAM_SIZE)
130 					continue;
131 				if (addr+size > MAX_RAM_SIZE)
132 					size = MAX_RAM_SIZE - (addr+size) + 1;
133 				/*
134 				 * memcpy/__copy_user prefetch, which
135 				 * will cause a bus error for
136 				 * KSEG/KUSEG addrs not backed by RAM.
137 				 * Hence, reserve some padding for the
138 				 * prefetch distance.
139 				 */
140 				if (size > 512)
141 					size -= 512;
142 				memblock_add(addr, size);
143 			}
144 			board_mem_region_addrs[board_mem_region_count] = addr;
145 			board_mem_region_sizes[board_mem_region_count] = size;
146 			board_mem_region_count++;
147 			if (board_mem_region_count ==
148 			    SIBYTE_MAX_MEM_REGIONS) {
149 				/*
150 				 * Too many regions.  Need to configure more
151 				 */
152 				while(1);
153 			}
154 		}
155 	}
156 #ifdef CONFIG_BLK_DEV_INITRD
157 	if (initrd_start) {
158 		memblock_add(initrd_pstart, initrd_pend - initrd_pstart);
159 		memblock_reserve(initrd_pstart, initrd_pend - initrd_pstart);
160 	}
161 #endif
162 }
163 
164 #ifdef CONFIG_BLK_DEV_INITRD
165 static int __init initrd_setup(char *str)
166 {
167 	char rdarg[64];
168 	int idx;
169 	char *tmp, *endptr;
170 	unsigned long initrd_size;
171 
172 	/* Make a copy of the initrd argument so we can smash it up here */
173 	for (idx = 0; idx < sizeof(rdarg)-1; idx++) {
174 		if (!str[idx] || (str[idx] == ' ')) break;
175 		rdarg[idx] = str[idx];
176 	}
177 
178 	rdarg[idx] = 0;
179 	str = rdarg;
180 
181 	/*
182 	 *Initrd location comes in the form "<hex size of ramdisk in bytes>@<location in memory>"
183 	 *  e.g. initrd=3abfd@80010000.	 This is set up by the loader.
184 	 */
185 	for (tmp = str; *tmp != '@'; tmp++) {
186 		if (!*tmp) {
187 			goto fail;
188 		}
189 	}
190 	*tmp = 0;
191 	tmp++;
192 	if (!*tmp) {
193 		goto fail;
194 	}
195 	initrd_size = simple_strtoul(str, &endptr, 16);
196 	if (*endptr) {
197 		*(tmp-1) = '@';
198 		goto fail;
199 	}
200 	*(tmp-1) = '@';
201 	initrd_start = simple_strtoul(tmp, &endptr, 16);
202 	if (*endptr) {
203 		goto fail;
204 	}
205 	initrd_end = initrd_start + initrd_size;
206 	printk("Found initrd of %lx@%lx\n", initrd_size, initrd_start);
207 	return 1;
208  fail:
209 	printk("Bad initrd argument.  Disabling initrd\n");
210 	initrd_start = 0;
211 	initrd_end = 0;
212 	return 1;
213 }
214 
215 #endif
216 
217 extern const struct plat_smp_ops sb_smp_ops;
218 extern const struct plat_smp_ops bcm1480_smp_ops;
219 
220 /*
221  * prom_init is called just after the cpu type is determined, from setup_arch()
222  */
223 void __init prom_init(void)
224 {
225 	uint64_t cfe_ept, cfe_handle;
226 	unsigned int cfe_eptseal;
227 	int argc = fw_arg0;
228 	char **envp = (char **) fw_arg2;
229 	int *prom_vec = (int *) fw_arg3;
230 
231 	_machine_restart   = cfe_linux_restart;
232 	_machine_halt	   = cfe_linux_halt;
233 	pm_power_off = cfe_linux_halt;
234 
235 	/*
236 	 * Check if a loader was used; if NOT, the 4 arguments are
237 	 * what CFE gives us (handle, 0, EPT and EPTSEAL)
238 	 */
239 	if (argc < 0) {
240 		cfe_handle = (uint64_t)(long)argc;
241 		cfe_ept = (long)envp;
242 		cfe_eptseal = (uint32_t)(unsigned long)prom_vec;
243 	} else {
244 		if ((int32_t)(long)prom_vec < 0) {
245 			/*
246 			 * Old loader; all it gives us is the handle,
247 			 * so use the "known" entrypoint and assume
248 			 * the seal.
249 			 */
250 			cfe_handle = (uint64_t)(long)prom_vec;
251 			cfe_ept = (uint64_t)((int32_t)0x9fc00500);
252 			cfe_eptseal = CFE_EPTSEAL;
253 		} else {
254 			/*
255 			 * Newer loaders bundle the handle/ept/eptseal
256 			 * Note: prom_vec is in the loader's useg
257 			 * which is still alive in the TLB.
258 			 */
259 			cfe_handle = (uint64_t)((int32_t *)prom_vec)[0];
260 			cfe_ept = (uint64_t)((int32_t *)prom_vec)[2];
261 			cfe_eptseal = (unsigned int)((uint32_t *)prom_vec)[3];
262 		}
263 	}
264 	if (cfe_eptseal != CFE_EPTSEAL) {
265 		/* too early for panic to do any good */
266 		printk("CFE's entrypoint seal doesn't match. Spinning.");
267 		while (1) ;
268 	}
269 	cfe_init(cfe_handle, cfe_ept);
270 	/*
271 	 * Get the handle for (at least) prom_putchar, possibly for
272 	 * boot console
273 	 */
274 	cfe_cons_handle = cfe_getstdhandle(CFE_STDHANDLE_CONSOLE);
275 	if (cfe_getenv("LINUX_CMDLINE", arcs_cmdline, COMMAND_LINE_SIZE) < 0) {
276 		if (argc >= 0) {
277 			/* The loader should have set the command line */
278 			/* too early for panic to do any good */
279 			printk("LINUX_CMDLINE not defined in cfe.");
280 			while (1) ;
281 		}
282 	}
283 
284 #ifdef CONFIG_BLK_DEV_INITRD
285 	{
286 		char *ptr;
287 		/* Need to find out early whether we've got an initrd.	So scan
288 		   the list looking now */
289 		for (ptr = arcs_cmdline; *ptr; ptr++) {
290 			while (*ptr == ' ') {
291 				ptr++;
292 			}
293 			if (!strncmp(ptr, "initrd=", 7)) {
294 				initrd_setup(ptr+7);
295 				break;
296 			} else {
297 				while (*ptr && (*ptr != ' ')) {
298 					ptr++;
299 				}
300 			}
301 		}
302 	}
303 #endif /* CONFIG_BLK_DEV_INITRD */
304 
305 	/* Not sure this is needed, but it's the safe way. */
306 	arcs_cmdline[COMMAND_LINE_SIZE-1] = 0;
307 
308 	prom_meminit();
309 
310 #if defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
311 	register_smp_ops(&sb_smp_ops);
312 #endif
313 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
314 	register_smp_ops(&bcm1480_smp_ops);
315 #endif
316 }
317 
318 void prom_putchar(char c)
319 {
320 	int ret;
321 
322 	while ((ret = cfe_write(cfe_cons_handle, &c, 1)) == 0)
323 		;
324 }
325