xref: /openbmc/u-boot/arch/sandbox/cpu/cpu.c (revision c00d0012)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  */
5 #define DEBUG
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <linux/libfdt.h>
10 #include <os.h>
11 #include <asm/io.h>
12 #include <asm/setjmp.h>
13 #include <asm/state.h>
14 #include <dm/root.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 /* Enable access to PCI memory with map_sysmem() */
19 static bool enable_pci_map;
20 
21 #ifdef CONFIG_PCI
22 /* Last device that was mapped into memory, and length of mapping */
23 static struct udevice *map_dev;
24 unsigned long map_len;
25 #endif
26 
27 void sandbox_exit(void)
28 {
29 	/* Do this here while it still has an effect */
30 	os_fd_restore();
31 	if (state_uninit())
32 		os_exit(2);
33 
34 	if (dm_uninit())
35 		os_exit(2);
36 
37 	/* This is considered normal termination for now */
38 	os_exit(0);
39 }
40 
41 /* delay x useconds */
42 void __udelay(unsigned long usec)
43 {
44 	struct sandbox_state *state = state_get_current();
45 
46 	if (!state->skip_delays)
47 		os_usleep(usec);
48 }
49 
50 int cleanup_before_linux(void)
51 {
52 	return 0;
53 }
54 
55 int cleanup_before_linux_select(int flags)
56 {
57 	return 0;
58 }
59 
60 /**
61  * is_in_sandbox_mem() - Checks if a pointer is within sandbox's emulated DRAM
62  *
63  * This provides a way to check if a pointer is owned by sandbox (and is within
64  * its RAM) or not. Sometimes pointers come from a test which conceptually runs
65  * output sandbox, potentially with direct access to the C-library malloc()
66  * function, or the sandbox stack (which is not actually within the emulated
67  * DRAM.
68  *
69  * Such pointers obviously cannot be mapped into sandbox's DRAM, so we must
70  * detect them an process them separately, by recording a mapping to a tag,
71  * which we can use to map back to the pointer later.
72  *
73  * @ptr: Pointer to check
74  * @return true if this is within sandbox emulated DRAM, false if not
75  */
76 static bool is_in_sandbox_mem(const void *ptr)
77 {
78 	return (const uint8_t *)ptr >= gd->arch.ram_buf &&
79 		(const uint8_t *)ptr < gd->arch.ram_buf + gd->ram_size;
80 }
81 
82 /**
83  * phys_to_virt() - Converts a sandbox RAM address to a pointer
84  *
85  * Sandbox uses U-Boot addresses from 0 to the size of DRAM. These index into
86  * the emulated DRAM buffer used by sandbox. This function converts such an
87  * address to a pointer into this buffer, which can be used to access the
88  * memory.
89  *
90  * If the address is outside this range, it is assumed to be a tag
91  */
92 void *phys_to_virt(phys_addr_t paddr)
93 {
94 	struct sandbox_mapmem_entry *mentry;
95 	struct sandbox_state *state;
96 
97 	/* If the address is within emulated DRAM, calculate the value */
98 	if (paddr < gd->ram_size)
99 		return (void *)(gd->arch.ram_buf + paddr);
100 
101 	/*
102 	 * Otherwise search out list of tags for the correct pointer previously
103 	 * created by map_to_sysmem()
104 	 */
105 	state = state_get_current();
106 	list_for_each_entry(mentry, &state->mapmem_head, sibling_node) {
107 		if (mentry->tag == paddr) {
108 			printf("%s: Used map from %lx to %p\n", __func__,
109 			       (ulong)paddr, mentry->ptr);
110 			return mentry->ptr;
111 		}
112 	}
113 
114 	printf("%s: Cannot map sandbox address %lx (SDRAM from 0 to %lx)\n",
115 	       __func__, (ulong)paddr, (ulong)gd->ram_size);
116 	os_abort();
117 
118 	/* Not reached */
119 	return NULL;
120 }
121 
122 struct sandbox_mapmem_entry *find_tag(const void *ptr)
123 {
124 	struct sandbox_mapmem_entry *mentry;
125 	struct sandbox_state *state = state_get_current();
126 
127 	list_for_each_entry(mentry, &state->mapmem_head, sibling_node) {
128 		if (mentry->ptr == ptr) {
129 			debug("%s: Used map from %p to %lx\n", __func__, ptr,
130 			      mentry->tag);
131 			return mentry;
132 		}
133 	}
134 	return NULL;
135 }
136 
137 phys_addr_t virt_to_phys(void *ptr)
138 {
139 	struct sandbox_mapmem_entry *mentry;
140 
141 	/*
142 	 * If it is in emulated RAM, don't bother looking for a tag. Just
143 	 * calculate the pointer using the provides offset into the RAM buffer.
144 	 */
145 	if (is_in_sandbox_mem(ptr))
146 		return (phys_addr_t)((uint8_t *)ptr - gd->arch.ram_buf);
147 
148 	mentry = find_tag(ptr);
149 	if (!mentry) {
150 		/* Abort so that gdb can be used here */
151 		printf("%s: Cannot map sandbox address %p (SDRAM from 0 to %lx)\n",
152 		       __func__, ptr, (ulong)gd->ram_size);
153 		os_abort();
154 	}
155 	printf("%s: Used map from %p to %lx\n", __func__, ptr, mentry->tag);
156 
157 	return mentry->tag;
158 }
159 
160 void *map_physmem(phys_addr_t paddr, unsigned long len, unsigned long flags)
161 {
162 #if defined(CONFIG_PCI) && !defined(CONFIG_SPL_BUILD)
163 	unsigned long plen = len;
164 	void *ptr;
165 
166 	map_dev = NULL;
167 	if (enable_pci_map && !pci_map_physmem(paddr, &len, &map_dev, &ptr)) {
168 		if (plen != len) {
169 			printf("%s: Warning: partial map at %x, wanted %lx, got %lx\n",
170 			       __func__, (uint)paddr, len, plen);
171 		}
172 		map_len = len;
173 		return ptr;
174 	}
175 #endif
176 
177 	return phys_to_virt(paddr);
178 }
179 
180 void unmap_physmem(const void *ptr, unsigned long flags)
181 {
182 #ifdef CONFIG_PCI
183 	if (map_dev) {
184 		pci_unmap_physmem(ptr, map_len, map_dev);
185 		map_dev = NULL;
186 	}
187 #endif
188 }
189 
190 phys_addr_t map_to_sysmem(const void *ptr)
191 {
192 	struct sandbox_mapmem_entry *mentry;
193 
194 	/*
195 	 * If it is in emulated RAM, don't bother creating a tag. Just return
196 	 * the offset into the RAM buffer.
197 	 */
198 	if (is_in_sandbox_mem(ptr))
199 		return (u8 *)ptr - gd->arch.ram_buf;
200 
201 	/*
202 	 * See if there is an existing tag with this pointer. If not, set up a
203 	 * new one.
204 	 */
205 	mentry = find_tag(ptr);
206 	if (!mentry) {
207 		struct sandbox_state *state = state_get_current();
208 
209 		mentry = malloc(sizeof(*mentry));
210 		if (!mentry) {
211 			printf("%s: Error: Out of memory\n", __func__);
212 			os_exit(ENOMEM);
213 		}
214 		mentry->tag = state->next_tag++;
215 		mentry->ptr = (void *)ptr;
216 		list_add_tail(&mentry->sibling_node, &state->mapmem_head);
217 		debug("%s: Added map from %p to %lx\n", __func__, ptr,
218 		      (ulong)mentry->tag);
219 	}
220 
221 	/*
222 	 * Return the tag as the address to use. A later call to map_sysmem()
223 	 * will return ptr
224 	 */
225 	return mentry->tag;
226 }
227 
228 void sandbox_set_enable_pci_map(int enable)
229 {
230 	enable_pci_map = enable;
231 }
232 
233 void flush_dcache_range(unsigned long start, unsigned long stop)
234 {
235 }
236 
237 void invalidate_dcache_range(unsigned long start, unsigned long stop)
238 {
239 }
240 
241 int sandbox_read_fdt_from_file(void)
242 {
243 	struct sandbox_state *state = state_get_current();
244 	const char *fname = state->fdt_fname;
245 	void *blob;
246 	loff_t size;
247 	int err;
248 	int fd;
249 
250 	blob = map_sysmem(CONFIG_SYS_FDT_LOAD_ADDR, 0);
251 	if (!state->fdt_fname) {
252 		err = fdt_create_empty_tree(blob, 256);
253 		if (!err)
254 			goto done;
255 		printf("Unable to create empty FDT: %s\n", fdt_strerror(err));
256 		return -EINVAL;
257 	}
258 
259 	err = os_get_filesize(fname, &size);
260 	if (err < 0) {
261 		printf("Failed to file FDT file '%s'\n", fname);
262 		return err;
263 	}
264 	fd = os_open(fname, OS_O_RDONLY);
265 	if (fd < 0) {
266 		printf("Failed to open FDT file '%s'\n", fname);
267 		return -EACCES;
268 	}
269 	if (os_read(fd, blob, size) != size) {
270 		os_close(fd);
271 		return -EIO;
272 	}
273 	os_close(fd);
274 
275 done:
276 	gd->fdt_blob = blob;
277 
278 	return 0;
279 }
280 
281 ulong timer_get_boot_us(void)
282 {
283 	static uint64_t base_count;
284 	uint64_t count = os_get_nsec();
285 
286 	if (!base_count)
287 		base_count = count;
288 
289 	return (count - base_count) / 1000;
290 }
291