xref: /openbmc/u-boot/arch/sandbox/cpu/cpu.c (revision 5830791d91d1200854ef78fcb32f808c8080f0f0)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * Copyright (c) 2011 The Chromium OS Authors.
4   */
5  
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  
sandbox_exit(void)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 */
__udelay(unsigned long usec)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  
cleanup_before_linux(void)50  int cleanup_before_linux(void)
51  {
52  	return 0;
53  }
54  
cleanup_before_linux_select(int flags)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   */
is_in_sandbox_mem(const void * ptr)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   */
phys_to_virt(phys_addr_t paddr)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  			debug("%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  
find_tag(const void * ptr)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  
virt_to_phys(void * ptr)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  	debug("%s: Used map from %p to %lx\n", __func__, ptr, mentry->tag);
156  
157  	return mentry->tag;
158  }
159  
map_physmem(phys_addr_t paddr,unsigned long len,unsigned long flags)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  
unmap_physmem(const void * ptr,unsigned long flags)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  
map_to_sysmem(const void * ptr)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  
sandbox_set_enable_pci_map(int enable)228  void sandbox_set_enable_pci_map(int enable)
229  {
230  	enable_pci_map = enable;
231  }
232  
flush_dcache_range(unsigned long start,unsigned long stop)233  void flush_dcache_range(unsigned long start, unsigned long stop)
234  {
235  }
236  
invalidate_dcache_range(unsigned long start,unsigned long stop)237  void invalidate_dcache_range(unsigned long start, unsigned long stop)
238  {
239  }
240  
sandbox_read_fdt_from_file(void)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  
timer_get_boot_us(void)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