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
38int cfe_cons_handle;
39
40#ifdef CONFIG_BLK_DEV_INITRD
41extern unsigned long initrd_start, initrd_end;
42#endif
43
44static 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
65static void __noreturn cfe_linux_restart(char *command)
66{
67	static const int zero;
68
69	cfe_linux_exit((void *)&zero);
70}
71
72static void __noreturn cfe_linux_halt(void)
73{
74	static const int one = 1;
75
76	cfe_linux_exit((void *)&one);
77}
78
79static __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
150static 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
202extern const struct plat_smp_ops sb_smp_ops;
203extern 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 */
208void __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
303void prom_putchar(char c)
304{
305	int ret;
306
307	while ((ret = cfe_write(cfe_cons_handle, &c, 1)) == 0)
308		;
309}
310