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5a5da7ce SG |
1 | Binman Entry Documentation |
2 | =========================== | |
3 | ||
4 | This file describes the entry types supported by binman. These entry types can | |
5 | be placed in an image one by one to build up a final firmware image. It is | |
6 | fairly easy to create new entry types. Just add a new file to the 'etype' | |
7 | directory. You can use the existing entries as examples. | |
8 | ||
9 | Note that some entries are subclasses of others, using and extending their | |
10 | features to produce new behaviours. | |
11 | ||
12 | ||
13 | ||
14 | Entry: blob: Entry containing an arbitrary binary blob | |
15 | ------------------------------------------------------ | |
16 | ||
17 | Note: This should not be used by itself. It is normally used as a parent | |
18 | class by other entry types. | |
19 | ||
20 | Properties / Entry arguments: | |
21 | - filename: Filename of file to read into entry | |
22 | ||
23 | This entry reads data from a file and places it in the entry. The | |
24 | default filename is often specified specified by the subclass. See for | |
25 | example the 'u_boot' entry which provides the filename 'u-boot.bin'. | |
26 | ||
27 | ||
28 | ||
ec127af0 SG |
29 | Entry: blob-named-by-arg: A blob entry which gets its filename property from its subclass |
30 | ----------------------------------------------------------------------------------------- | |
31 | ||
32 | Properties / Entry arguments: | |
33 | - <xxx>-path: Filename containing the contents of this entry (optional, | |
34 | defaults to 0) | |
35 | ||
36 | where <xxx> is the blob_fname argument to the constructor. | |
37 | ||
38 | This entry cannot be used directly. Instead, it is used as a parent class | |
39 | for another entry, which defined blob_fname. This parameter is used to | |
40 | set the entry-arg or property containing the filename. The entry-arg or | |
41 | property is in turn used to set the actual filename. | |
42 | ||
43 | See cros_ec_rw for an example of this. | |
44 | ||
45 | ||
46 | ||
47 | Entry: cros-ec-rw: A blob entry which contains a Chromium OS read-write EC image | |
48 | -------------------------------------------------------------------------------- | |
49 | ||
50 | Properties / Entry arguments: | |
51 | - cros-ec-rw-path: Filename containing the EC image | |
52 | ||
53 | This entry holds a Chromium OS EC (embedded controller) image, for use in | |
54 | updating the EC on startup via software sync. | |
55 | ||
56 | ||
57 | ||
3af8e49c SG |
58 | Entry: fill: An entry which is filled to a particular byte value |
59 | ---------------------------------------------------------------- | |
60 | ||
61 | Properties / Entry arguments: | |
62 | - fill-byte: Byte to use to fill the entry | |
63 | ||
64 | Note that the size property must be set since otherwise this entry does not | |
65 | know how large it should be. | |
66 | ||
67 | You can often achieve the same effect using the pad-byte property of the | |
68 | overall image, in that the space between entries will then be padded with | |
69 | that byte. But this entry is sometimes useful for explicitly setting the | |
70 | byte value of a region. | |
71 | ||
72 | ||
73 | ||
11e36cce SG |
74 | Entry: fmap: An entry which contains an Fmap section |
75 | ---------------------------------------------------- | |
76 | ||
77 | Properties / Entry arguments: | |
78 | None | |
79 | ||
80 | FMAP is a simple format used by flashrom, an open-source utility for | |
81 | reading and writing the SPI flash, typically on x86 CPUs. The format | |
82 | provides flashrom with a list of areas, so it knows what it in the flash. | |
83 | It can then read or write just a single area, instead of the whole flash. | |
84 | ||
85 | The format is defined by the flashrom project, in the file lib/fmap.h - | |
86 | see www.flashrom.org/Flashrom for more information. | |
87 | ||
88 | When used, this entry will be populated with an FMAP which reflects the | |
89 | entries in the current image. Note that any hierarchy is squashed, since | |
90 | FMAP does not support this. | |
91 | ||
92 | ||
93 | ||
0ef87aa3 SG |
94 | Entry: gbb: An entry which contains a Chromium OS Google Binary Block |
95 | --------------------------------------------------------------------- | |
96 | ||
97 | Properties / Entry arguments: | |
98 | - hardware-id: Hardware ID to use for this build (a string) | |
99 | - keydir: Directory containing the public keys to use | |
100 | - bmpblk: Filename containing images used by recovery | |
101 | ||
102 | Chromium OS uses a GBB to store various pieces of information, in particular | |
103 | the root and recovery keys that are used to verify the boot process. Some | |
104 | more details are here: | |
105 | ||
106 | https://www.chromium.org/chromium-os/firmware-porting-guide/2-concepts | |
107 | ||
108 | but note that the page dates from 2013 so is quite out of date. See | |
109 | README.chromium for how to obtain the required keys and tools. | |
110 | ||
111 | ||
112 | ||
5a5da7ce SG |
113 | Entry: intel-cmc: Entry containing an Intel Chipset Micro Code (CMC) file |
114 | ------------------------------------------------------------------------- | |
115 | ||
116 | Properties / Entry arguments: | |
117 | - filename: Filename of file to read into entry | |
118 | ||
119 | This file contains microcode for some devices in a special format. An | |
120 | example filename is 'Microcode/C0_22211.BIN'. | |
121 | ||
122 | See README.x86 for information about x86 binary blobs. | |
123 | ||
124 | ||
125 | ||
126 | Entry: intel-descriptor: Intel flash descriptor block (4KB) | |
127 | ----------------------------------------------------------- | |
128 | ||
129 | Properties / Entry arguments: | |
130 | filename: Filename of file containing the descriptor. This is typically | |
131 | a 4KB binary file, sometimes called 'descriptor.bin' | |
132 | ||
133 | This entry is placed at the start of flash and provides information about | |
134 | the SPI flash regions. In particular it provides the base address and | |
135 | size of the ME (Management Engine) region, allowing us to place the ME | |
136 | binary in the right place. | |
137 | ||
138 | With this entry in your image, the position of the 'intel-me' entry will be | |
139 | fixed in the image, which avoids you needed to specify an offset for that | |
140 | region. This is useful, because it is not possible to change the position | |
141 | of the ME region without updating the descriptor. | |
142 | ||
143 | See README.x86 for information about x86 binary blobs. | |
144 | ||
145 | ||
146 | ||
147 | Entry: intel-fsp: Entry containing an Intel Firmware Support Package (FSP) file | |
148 | ------------------------------------------------------------------------------- | |
149 | ||
150 | Properties / Entry arguments: | |
151 | - filename: Filename of file to read into entry | |
152 | ||
153 | This file contains binary blobs which are used on some devices to make the | |
154 | platform work. U-Boot executes this code since it is not possible to set up | |
155 | the hardware using U-Boot open-source code. Documentation is typically not | |
156 | available in sufficient detail to allow this. | |
157 | ||
158 | An example filename is 'FSP/QUEENSBAY_FSP_GOLD_001_20-DECEMBER-2013.fd' | |
159 | ||
160 | See README.x86 for information about x86 binary blobs. | |
161 | ||
162 | ||
163 | ||
164 | Entry: intel-me: Entry containing an Intel Management Engine (ME) file | |
165 | ---------------------------------------------------------------------- | |
166 | ||
167 | Properties / Entry arguments: | |
168 | - filename: Filename of file to read into entry | |
169 | ||
170 | This file contains code used by the SoC that is required to make it work. | |
171 | The Management Engine is like a background task that runs things that are | |
172 | not clearly documented, but may include keyboard, deplay and network | |
173 | access. For platform that use ME it is not possible to disable it. U-Boot | |
174 | does not directly execute code in the ME binary. | |
175 | ||
176 | A typical filename is 'me.bin'. | |
177 | ||
178 | See README.x86 for information about x86 binary blobs. | |
179 | ||
180 | ||
181 | ||
182 | Entry: intel-mrc: Entry containing an Intel Memory Reference Code (MRC) file | |
183 | ---------------------------------------------------------------------------- | |
184 | ||
185 | Properties / Entry arguments: | |
186 | - filename: Filename of file to read into entry | |
187 | ||
188 | This file contains code for setting up the SDRAM on some Intel systems. This | |
189 | is executed by U-Boot when needed early during startup. A typical filename | |
190 | is 'mrc.bin'. | |
191 | ||
192 | See README.x86 for information about x86 binary blobs. | |
193 | ||
194 | ||
195 | ||
196 | Entry: intel-vbt: Entry containing an Intel Video BIOS Table (VBT) file | |
197 | ----------------------------------------------------------------------- | |
198 | ||
199 | Properties / Entry arguments: | |
200 | - filename: Filename of file to read into entry | |
201 | ||
202 | This file contains code that sets up the integrated graphics subsystem on | |
203 | some Intel SoCs. U-Boot executes this when the display is started up. | |
204 | ||
205 | See README.x86 for information about Intel binary blobs. | |
206 | ||
207 | ||
208 | ||
209 | Entry: intel-vga: Entry containing an Intel Video Graphics Adaptor (VGA) file | |
210 | ----------------------------------------------------------------------------- | |
211 | ||
212 | Properties / Entry arguments: | |
213 | - filename: Filename of file to read into entry | |
214 | ||
215 | This file contains code that sets up the integrated graphics subsystem on | |
216 | some Intel SoCs. U-Boot executes this when the display is started up. | |
217 | ||
218 | This is similar to the VBT file but in a different format. | |
219 | ||
220 | See README.x86 for information about Intel binary blobs. | |
221 | ||
222 | ||
223 | ||
224 | Entry: section: Entry that contains other entries | |
225 | ------------------------------------------------- | |
226 | ||
227 | Properties / Entry arguments: (see binman README for more information) | |
228 | - size: Size of section in bytes | |
229 | - align-size: Align size to a particular power of two | |
230 | - pad-before: Add padding before the entry | |
231 | - pad-after: Add padding after the entry | |
232 | - pad-byte: Pad byte to use when padding | |
233 | - sort-by-offset: Reorder the entries by offset | |
234 | - end-at-4gb: Used to build an x86 ROM which ends at 4GB (2^32) | |
235 | - name-prefix: Adds a prefix to the name of every entry in the section | |
236 | when writing out the map | |
237 | ||
238 | A section is an entry which can contain other entries, thus allowing | |
239 | hierarchical images to be created. See 'Sections and hierarchical images' | |
240 | in the binman README for more information. | |
241 | ||
242 | ||
243 | ||
244 | Entry: text: An entry which contains text | |
245 | ----------------------------------------- | |
246 | ||
247 | The text can be provided either in the node itself or by a command-line | |
248 | argument. There is a level of indirection to allow multiple text strings | |
249 | and sharing of text. | |
250 | ||
251 | Properties / Entry arguments: | |
252 | text-label: The value of this string indicates the property / entry-arg | |
253 | that contains the string to place in the entry | |
254 | <xxx> (actual name is the value of text-label): contains the string to | |
255 | place in the entry. | |
256 | ||
257 | Example node: | |
258 | ||
259 | text { | |
260 | size = <50>; | |
261 | text-label = "message"; | |
262 | }; | |
263 | ||
264 | You can then use: | |
265 | ||
266 | binman -amessage="this is my message" | |
267 | ||
268 | and binman will insert that string into the entry. | |
269 | ||
270 | It is also possible to put the string directly in the node: | |
271 | ||
272 | text { | |
273 | size = <8>; | |
274 | text-label = "message"; | |
275 | message = "a message directly in the node" | |
276 | }; | |
277 | ||
278 | The text is not itself nul-terminated. This can be achieved, if required, | |
279 | by setting the size of the entry to something larger than the text. | |
280 | ||
281 | ||
282 | ||
283 | Entry: u-boot: U-Boot flat binary | |
284 | --------------------------------- | |
285 | ||
286 | Properties / Entry arguments: | |
287 | - filename: Filename of u-boot.bin (default 'u-boot.bin') | |
288 | ||
289 | This is the U-Boot binary, containing relocation information to allow it | |
290 | to relocate itself at runtime. The binary typically includes a device tree | |
291 | blob at the end of it. Use u_boot_nodtb if you want to package the device | |
292 | tree separately. | |
293 | ||
294 | U-Boot can access binman symbols at runtime. See: | |
295 | ||
296 | 'Access to binman entry offsets at run time (fdt)' | |
297 | ||
298 | in the binman README for more information. | |
299 | ||
300 | ||
301 | ||
302 | Entry: u-boot-dtb: U-Boot device tree | |
303 | ------------------------------------- | |
304 | ||
305 | Properties / Entry arguments: | |
306 | - filename: Filename of u-boot.dtb (default 'u-boot.dtb') | |
307 | ||
308 | This is the U-Boot device tree, containing configuration information for | |
309 | U-Boot. U-Boot needs this to know what devices are present and which drivers | |
310 | to activate. | |
311 | ||
312 | ||
313 | ||
314 | Entry: u-boot-dtb-with-ucode: A U-Boot device tree file, with the microcode removed | |
315 | ----------------------------------------------------------------------------------- | |
316 | ||
317 | Properties / Entry arguments: | |
318 | - filename: Filename of u-boot.dtb (default 'u-boot.dtb') | |
319 | ||
320 | See Entry_u_boot_ucode for full details of the three entries involved in | |
321 | this process. This entry provides the U-Boot device-tree file, which | |
322 | contains the microcode. If the microcode is not being collated into one | |
323 | place then the offset and size of the microcode is recorded by this entry, | |
324 | for use by u_boot_with_ucode_ptr. If it is being collated, then this | |
325 | entry deletes the microcode from the device tree (to save space) and makes | |
326 | it available to u_boot_ucode. | |
327 | ||
328 | ||
329 | ||
330 | Entry: u-boot-img: U-Boot legacy image | |
331 | -------------------------------------- | |
332 | ||
333 | Properties / Entry arguments: | |
334 | - filename: Filename of u-boot.img (default 'u-boot.img') | |
335 | ||
336 | This is the U-Boot binary as a packaged image, in legacy format. It has a | |
337 | header which allows it to be loaded at the correct address for execution. | |
338 | ||
339 | You should use FIT (Flat Image Tree) instead of the legacy image for new | |
340 | applications. | |
341 | ||
342 | ||
343 | ||
344 | Entry: u-boot-nodtb: U-Boot flat binary without device tree appended | |
345 | -------------------------------------------------------------------- | |
346 | ||
347 | Properties / Entry arguments: | |
348 | - filename: Filename of u-boot.bin (default 'u-boot-nodtb.bin') | |
349 | ||
350 | This is the U-Boot binary, containing relocation information to allow it | |
351 | to relocate itself at runtime. It does not include a device tree blob at | |
352 | the end of it so normally cannot work without it. You can add a u_boot_dtb | |
353 | entry after this one, or use a u_boot entry instead (which contains both | |
354 | U-Boot and the device tree). | |
355 | ||
356 | ||
357 | ||
358 | Entry: u-boot-spl: U-Boot SPL binary | |
359 | ------------------------------------ | |
360 | ||
361 | Properties / Entry arguments: | |
362 | - filename: Filename of u-boot-spl.bin (default 'spl/u-boot-spl.bin') | |
363 | ||
364 | This is the U-Boot SPL (Secondary Program Loader) binary. This is a small | |
365 | binary which loads before U-Boot proper, typically into on-chip SRAM. It is | |
366 | responsible for locating, loading and jumping to U-Boot. Note that SPL is | |
367 | not relocatable so must be loaded to the correct address in SRAM, or written | |
b8ef5b6b | 368 | to run from the correct address if direct flash execution is possible (e.g. |
5a5da7ce SG |
369 | on x86 devices). |
370 | ||
371 | SPL can access binman symbols at runtime. See: | |
372 | ||
373 | 'Access to binman entry offsets at run time (symbols)' | |
374 | ||
375 | in the binman README for more information. | |
376 | ||
377 | The ELF file 'spl/u-boot-spl' must also be available for this to work, since | |
378 | binman uses that to look up symbols to write into the SPL binary. | |
379 | ||
380 | ||
381 | ||
382 | Entry: u-boot-spl-bss-pad: U-Boot SPL binary padded with a BSS region | |
383 | --------------------------------------------------------------------- | |
384 | ||
385 | Properties / Entry arguments: | |
386 | None | |
387 | ||
388 | This is similar to u_boot_spl except that padding is added after the SPL | |
389 | binary to cover the BSS (Block Started by Symbol) region. This region holds | |
390 | the various used by SPL. It is set to 0 by SPL when it starts up. If you | |
391 | want to append data to the SPL image (such as a device tree file), you must | |
392 | pad out the BSS region to avoid the data overlapping with U-Boot variables. | |
393 | This entry is useful in that case. It automatically pads out the entry size | |
394 | to cover both the code, data and BSS. | |
395 | ||
396 | The ELF file 'spl/u-boot-spl' must also be available for this to work, since | |
397 | binman uses that to look up the BSS address. | |
398 | ||
399 | ||
400 | ||
401 | Entry: u-boot-spl-dtb: U-Boot SPL device tree | |
402 | --------------------------------------------- | |
403 | ||
404 | Properties / Entry arguments: | |
405 | - filename: Filename of u-boot.dtb (default 'spl/u-boot-spl.dtb') | |
406 | ||
407 | This is the SPL device tree, containing configuration information for | |
408 | SPL. SPL needs this to know what devices are present and which drivers | |
409 | to activate. | |
410 | ||
411 | ||
412 | ||
413 | Entry: u-boot-spl-nodtb: SPL binary without device tree appended | |
414 | ---------------------------------------------------------------- | |
415 | ||
416 | Properties / Entry arguments: | |
417 | - filename: Filename of spl/u-boot-spl-nodtb.bin (default | |
418 | 'spl/u-boot-spl-nodtb.bin') | |
419 | ||
420 | This is the U-Boot SPL binary, It does not include a device tree blob at | |
421 | the end of it so may not be able to work without it, assuming SPL needs | |
422 | a device tree to operation on your platform. You can add a u_boot_spl_dtb | |
423 | entry after this one, or use a u_boot_spl entry instead (which contains | |
424 | both SPL and the device tree). | |
425 | ||
426 | ||
427 | ||
428 | Entry: u-boot-spl-with-ucode-ptr: U-Boot SPL with embedded microcode pointer | |
429 | ---------------------------------------------------------------------------- | |
430 | ||
431 | See Entry_u_boot_ucode for full details of the entries involved in this | |
432 | process. | |
433 | ||
434 | ||
435 | ||
b8ef5b6b SG |
436 | Entry: u-boot-tpl: U-Boot TPL binary |
437 | ------------------------------------ | |
438 | ||
439 | Properties / Entry arguments: | |
440 | - filename: Filename of u-boot-tpl.bin (default 'tpl/u-boot-tpl.bin') | |
441 | ||
442 | This is the U-Boot TPL (Tertiary Program Loader) binary. This is a small | |
443 | binary which loads before SPL, typically into on-chip SRAM. It is | |
444 | responsible for locating, loading and jumping to SPL, the next-stage | |
445 | loader. Note that SPL is not relocatable so must be loaded to the correct | |
446 | address in SRAM, or written to run from the correct address if direct | |
447 | flash execution is possible (e.g. on x86 devices). | |
448 | ||
449 | SPL can access binman symbols at runtime. See: | |
450 | ||
451 | 'Access to binman entry offsets at run time (symbols)' | |
452 | ||
453 | in the binman README for more information. | |
454 | ||
455 | The ELF file 'tpl/u-boot-tpl' must also be available for this to work, since | |
456 | binman uses that to look up symbols to write into the TPL binary. | |
457 | ||
458 | ||
459 | ||
460 | Entry: u-boot-tpl-dtb: U-Boot TPL device tree | |
461 | --------------------------------------------- | |
462 | ||
463 | Properties / Entry arguments: | |
464 | - filename: Filename of u-boot.dtb (default 'tpl/u-boot-tpl.dtb') | |
465 | ||
466 | This is the TPL device tree, containing configuration information for | |
467 | TPL. TPL needs this to know what devices are present and which drivers | |
468 | to activate. | |
469 | ||
470 | ||
471 | ||
5a5da7ce SG |
472 | Entry: u-boot-ucode: U-Boot microcode block |
473 | ------------------------------------------- | |
474 | ||
475 | Properties / Entry arguments: | |
476 | None | |
477 | ||
478 | The contents of this entry are filled in automatically by other entries | |
479 | which must also be in the image. | |
480 | ||
481 | U-Boot on x86 needs a single block of microcode. This is collected from | |
482 | the various microcode update nodes in the device tree. It is also unable | |
483 | to read the microcode from the device tree on platforms that use FSP | |
484 | (Firmware Support Package) binaries, because the API requires that the | |
485 | microcode is supplied before there is any SRAM available to use (i.e. | |
486 | the FSP sets up the SRAM / cache-as-RAM but does so in the call that | |
487 | requires the microcode!). To keep things simple, all x86 platforms handle | |
488 | microcode the same way in U-Boot (even non-FSP platforms). This is that | |
489 | a table is placed at _dt_ucode_base_size containing the base address and | |
490 | size of the microcode. This is either passed to the FSP (for FSP | |
491 | platforms), or used to set up the microcode (for non-FSP platforms). | |
492 | This all happens in the build system since it is the only way to get | |
493 | the microcode into a single blob and accessible without SRAM. | |
494 | ||
495 | There are two cases to handle. If there is only one microcode blob in | |
496 | the device tree, then the ucode pointer it set to point to that. This | |
497 | entry (u-boot-ucode) is empty. If there is more than one update, then | |
498 | this entry holds the concatenation of all updates, and the device tree | |
499 | entry (u-boot-dtb-with-ucode) is updated to remove the microcode. This | |
500 | last step ensures that that the microcode appears in one contiguous | |
501 | block in the image and is not unnecessarily duplicated in the device | |
502 | tree. It is referred to as 'collation' here. | |
503 | ||
504 | Entry types that have a part to play in handling microcode: | |
505 | ||
506 | Entry_u_boot_with_ucode_ptr: | |
507 | Contains u-boot-nodtb.bin (i.e. U-Boot without the device tree). | |
508 | It updates it with the address and size of the microcode so that | |
509 | U-Boot can find it early on start-up. | |
510 | Entry_u_boot_dtb_with_ucode: | |
511 | Contains u-boot.dtb. It stores the microcode in a | |
512 | 'self.ucode_data' property, which is then read by this class to | |
513 | obtain the microcode if needed. If collation is performed, it | |
514 | removes the microcode from the device tree. | |
515 | Entry_u_boot_ucode: | |
516 | This class. If collation is enabled it reads the microcode from | |
517 | the Entry_u_boot_dtb_with_ucode entry, and uses it as the | |
518 | contents of this entry. | |
519 | ||
520 | ||
521 | ||
522 | Entry: u-boot-with-ucode-ptr: U-Boot with embedded microcode pointer | |
523 | -------------------------------------------------------------------- | |
524 | ||
525 | Properties / Entry arguments: | |
526 | - filename: Filename of u-boot-nodtb.dtb (default 'u-boot-nodtb.dtb') | |
f0693038 SG |
527 | - optional-ucode: boolean property to make microcode optional. If the |
528 | u-boot.bin image does not include microcode, no error will | |
529 | be generated. | |
5a5da7ce SG |
530 | |
531 | See Entry_u_boot_ucode for full details of the three entries involved in | |
532 | this process. This entry updates U-Boot with the offset and size of the | |
533 | microcode, to allow early x86 boot code to find it without doing anything | |
534 | complicated. Otherwise it is the same as the u_boot entry. | |
535 | ||
536 | ||
537 | ||
24d0d3c3 SG |
538 | Entry: vblock: An entry which contains a Chromium OS verified boot block |
539 | ------------------------------------------------------------------------ | |
540 | ||
541 | Properties / Entry arguments: | |
542 | - keydir: Directory containing the public keys to use | |
543 | - keyblock: Name of the key file to use (inside keydir) | |
544 | - signprivate: Name of provide key file to use (inside keydir) | |
545 | - version: Version number of the vblock (typically 1) | |
546 | - kernelkey: Name of the kernel key to use (inside keydir) | |
547 | - preamble-flags: Value of the vboot preamble flags (typically 0) | |
548 | ||
a326b495 SG |
549 | Output files: |
550 | - input.<unique_name> - input file passed to futility | |
551 | - vblock.<unique_name> - output file generated by futility (which is | |
552 | used as the entry contents) | |
553 | ||
f0693038 | 554 | Chromium OS signs the read-write firmware and kernel, writing the signature |
24d0d3c3 SG |
555 | in this block. This allows U-Boot to verify that the next firmware stage |
556 | and kernel are genuine. | |
557 | ||
558 | ||
559 | ||
5a5da7ce SG |
560 | Entry: x86-start16: x86 16-bit start-up code for U-Boot |
561 | ------------------------------------------------------- | |
562 | ||
563 | Properties / Entry arguments: | |
564 | - filename: Filename of u-boot-x86-16bit.bin (default | |
565 | 'u-boot-x86-16bit.bin') | |
566 | ||
567 | x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code | |
568 | must be placed at a particular address. This entry holds that code. It is | |
569 | typically placed at offset CONFIG_SYS_X86_START16. The code is responsible | |
570 | for changing to 32-bit mode and jumping to U-Boot's entry point, which | |
571 | requires 32-bit mode (for 32-bit U-Boot). | |
572 | ||
573 | For 64-bit U-Boot, the 'x86_start16_spl' entry type is used instead. | |
574 | ||
575 | ||
576 | ||
577 | Entry: x86-start16-spl: x86 16-bit start-up code for SPL | |
578 | -------------------------------------------------------- | |
579 | ||
580 | Properties / Entry arguments: | |
581 | - filename: Filename of spl/u-boot-x86-16bit-spl.bin (default | |
582 | 'spl/u-boot-x86-16bit-spl.bin') | |
583 | ||
584 | x86 CPUs start up in 16-bit mode, even if they are 64-bit CPUs. This code | |
585 | must be placed at a particular address. This entry holds that code. It is | |
586 | typically placed at offset CONFIG_SYS_X86_START16. The code is responsible | |
587 | for changing to 32-bit mode and starting SPL, which in turn changes to | |
588 | 64-bit mode and jumps to U-Boot (for 64-bit U-Boot). | |
589 | ||
590 | For 32-bit U-Boot, the 'x86_start16' entry type is used instead. | |
591 | ||
592 | ||
593 | ||
35b384cb SG |
594 | Entry: x86-start16-tpl: x86 16-bit start-up code for TPL |
595 | -------------------------------------------------------- | |
596 | ||
597 | Properties / Entry arguments: | |
598 | - filename: Filename of tpl/u-boot-x86-16bit-tpl.bin (default | |
599 | 'tpl/u-boot-x86-16bit-tpl.bin') | |
600 | ||
601 | x86 CPUs start up in 16-bit mode, even if they are 64-bit CPUs. This code | |
602 | must be placed at a particular address. This entry holds that code. It is | |
603 | typically placed at offset CONFIG_SYS_X86_START16. The code is responsible | |
604 | for changing to 32-bit mode and starting TPL, which in turn jumps to SPL. | |
605 | ||
606 | If TPL is not being used, the 'x86_start16_spl or 'x86_start16' entry types | |
607 | may be used instead. | |
608 | ||
609 | ||
610 |