blob: c96e26e6b782c41436a1e7e53f538cfe14270d72 [file] [log] [blame]
Simon Glassdf93d902014-02-27 13:26:12 -07001/*
2 * Chromium OS cros_ec driver - sandbox emulation
3 *
4 * Copyright (c) 2013 The Chromium OS Authors.
5 *
6 * SPDX-License-Identifier: GPL-2.0+
7 */
8
9#include <common.h>
10#include <cros_ec.h>
Simon Glassbe995a82014-10-13 23:42:15 -060011#include <dm.h>
Simon Glassdf93d902014-02-27 13:26:12 -070012#include <ec_commands.h>
13#include <errno.h>
14#include <hash.h>
15#include <malloc.h>
16#include <os.h>
Jeroen Hofstee2b9912e2014-06-12 22:27:12 +020017#include <u-boot/sha256.h>
Simon Glassdf93d902014-02-27 13:26:12 -070018#include <spi.h>
19#include <asm/state.h>
20#include <asm/sdl.h>
21#include <linux/input.h>
22
23/*
24 * Ultimately it shold be possible to connect an Chrome OS EC emulation
25 * to U-Boot and remove all of this code. But this provides a test
26 * environment for bringing up chromeos_sandbox and demonstrating its
27 * utility.
28 *
29 * This emulation includes the following:
30 *
31 * 1. Emulation of the keyboard, by converting keypresses received from SDL
32 * into key scan data, passed back from the EC as key scan messages. The
33 * key layout is read from the device tree.
34 *
35 * 2. Emulation of vboot context - so this can be read/written as required.
36 *
37 * 3. Save/restore of EC state, so that the vboot context, flash memory
38 * contents and current image can be preserved across boots. This is important
39 * since the EC is supposed to continue running even if the AP resets.
40 *
41 * 4. Some event support, in particular allowing Escape to be pressed on boot
42 * to enter recovery mode. The EC passes this to U-Boot through the normal
43 * event message.
44 *
45 * 5. Flash read/write/erase support, so that software sync works. The
46 * protect messages are supported but no protection is implemented.
47 *
48 * 6. Hashing of the EC image, again to support software sync.
49 *
50 * Other features can be added, although a better path is probably to link
51 * the EC image in with U-Boot (Vic has demonstrated a prototype for this).
52 */
53
54DECLARE_GLOBAL_DATA_PTR;
55
56#define KEYBOARD_ROWS 8
57#define KEYBOARD_COLS 13
58
59/* A single entry of the key matrix */
60struct ec_keymatrix_entry {
61 int row; /* key matrix row */
62 int col; /* key matrix column */
63 int keycode; /* corresponding linux key code */
64};
65
66/**
67 * struct ec_state - Information about the EC state
68 *
69 * @vbnv_context: Vboot context data stored by EC
70 * @ec_config: FDT config information about the EC (e.g. flashmap)
71 * @flash_data: Contents of flash memory
72 * @flash_data_len: Size of flash memory
73 * @current_image: Current image the EC is running
74 * @matrix_count: Number of keys to decode in matrix
75 * @matrix: Information about keyboard matrix
76 * @keyscan: Current keyscan information (bit set for each row/column pressed)
77 * @recovery_req: Keyboard recovery requested
78 */
79struct ec_state {
80 uint8_t vbnv_context[EC_VBNV_BLOCK_SIZE];
81 struct fdt_cros_ec ec_config;
82 uint8_t *flash_data;
83 int flash_data_len;
84 enum ec_current_image current_image;
85 int matrix_count;
86 struct ec_keymatrix_entry *matrix; /* the key matrix info */
87 uint8_t keyscan[KEYBOARD_COLS];
88 bool recovery_req;
Simon Glassbe995a82014-10-13 23:42:15 -060089} s_state, *g_state;
Simon Glassdf93d902014-02-27 13:26:12 -070090
91/**
92 * cros_ec_read_state() - read the sandbox EC state from the state file
93 *
94 * If data is available, then blob and node will provide access to it. If
95 * not this function sets up an empty EC.
96 *
97 * @param blob: Pointer to device tree blob, or NULL if no data to read
98 * @param node: Node offset to read from
99 */
100static int cros_ec_read_state(const void *blob, int node)
101{
102 struct ec_state *ec = &s_state;
103 const char *prop;
104 int len;
105
106 /* Set everything to defaults */
107 ec->current_image = EC_IMAGE_RO;
108 if (!blob)
109 return 0;
110
111 /* Read the data if available */
112 ec->current_image = fdtdec_get_int(blob, node, "current-image",
113 EC_IMAGE_RO);
114 prop = fdt_getprop(blob, node, "vbnv-context", &len);
115 if (prop && len == sizeof(ec->vbnv_context))
116 memcpy(ec->vbnv_context, prop, len);
117
118 prop = fdt_getprop(blob, node, "flash-data", &len);
119 if (prop) {
120 ec->flash_data_len = len;
121 ec->flash_data = os_malloc(len);
122 if (!ec->flash_data)
123 return -ENOMEM;
124 memcpy(ec->flash_data, prop, len);
125 debug("%s: Loaded EC flash data size %#x\n", __func__, len);
126 }
127
128 return 0;
129}
130
131/**
132 * cros_ec_write_state() - Write out our state to the state file
133 *
134 * The caller will ensure that there is a node ready for the state. The node
135 * may already contain the old state, in which case it is overridden.
136 *
137 * @param blob: Device tree blob holding state
138 * @param node: Node to write our state into
139 */
140static int cros_ec_write_state(void *blob, int node)
141{
Simon Glassbe995a82014-10-13 23:42:15 -0600142 struct ec_state *ec = g_state;
Simon Glassdf93d902014-02-27 13:26:12 -0700143
144 /* We are guaranteed enough space to write basic properties */
145 fdt_setprop_u32(blob, node, "current-image", ec->current_image);
146 fdt_setprop(blob, node, "vbnv-context", ec->vbnv_context,
147 sizeof(ec->vbnv_context));
148 return state_setprop(node, "flash-data", ec->flash_data,
149 ec->ec_config.flash.length);
150}
151
152SANDBOX_STATE_IO(cros_ec, "google,cros-ec", cros_ec_read_state,
153 cros_ec_write_state);
154
155/**
156 * Return the number of bytes used in the specified image.
157 *
158 * This is the actual size of code+data in the image, as opposed to the
159 * amount of space reserved in flash for that image. This code is similar to
160 * that used by the real EC code base.
161 *
162 * @param ec Current emulated EC state
163 * @param entry Flash map entry containing the image to check
164 * @return actual image size in bytes, 0 if the image contains no content or
165 * error.
166 */
167static int get_image_used(struct ec_state *ec, struct fmap_entry *entry)
168{
169 int size;
170
171 /*
172 * Scan backwards looking for 0xea byte, which is by definition the
173 * last byte of the image. See ec.lds.S for how this is inserted at
174 * the end of the image.
175 */
176 for (size = entry->length - 1;
177 size > 0 && ec->flash_data[entry->offset + size] != 0xea;
178 size--)
179 ;
180
181 return size ? size + 1 : 0; /* 0xea byte IS part of the image */
182}
183
184/**
185 * Read the key matrix from the device tree
186 *
187 * Keymap entries in the fdt take the form of 0xRRCCKKKK where
188 * RR=Row CC=Column KKKK=Key Code
189 *
190 * @param ec Current emulated EC state
Simon Glassdf93d902014-02-27 13:26:12 -0700191 * @param node Keyboard node of device tree containing keyscan information
192 * @return 0 if ok, -1 on error
193 */
Simon Glass2ec9d172017-05-18 20:09:23 -0600194static int keyscan_read_fdt_matrix(struct ec_state *ec, ofnode node)
Simon Glassdf93d902014-02-27 13:26:12 -0700195{
196 const u32 *cell;
197 int upto;
198 int len;
199
Simon Glass2ec9d172017-05-18 20:09:23 -0600200 cell = ofnode_read_prop(node, "linux,keymap", &len);
Simon Glassdf93d902014-02-27 13:26:12 -0700201 ec->matrix_count = len / 4;
202 ec->matrix = calloc(ec->matrix_count, sizeof(*ec->matrix));
203 if (!ec->matrix) {
204 debug("%s: Out of memory for key matrix\n", __func__);
205 return -1;
206 }
207
208 /* Now read the data */
209 for (upto = 0; upto < ec->matrix_count; upto++) {
210 struct ec_keymatrix_entry *matrix = &ec->matrix[upto];
211 u32 word;
212
213 word = fdt32_to_cpu(*cell++);
214 matrix->row = word >> 24;
215 matrix->col = (word >> 16) & 0xff;
216 matrix->keycode = word & 0xffff;
217
218 /* Hard-code some sanity limits for now */
219 if (matrix->row >= KEYBOARD_ROWS ||
220 matrix->col >= KEYBOARD_COLS) {
221 debug("%s: Matrix pos out of range (%d,%d)\n",
222 __func__, matrix->row, matrix->col);
223 return -1;
224 }
225 }
226
227 if (upto != ec->matrix_count) {
228 debug("%s: Read mismatch from key matrix\n", __func__);
229 return -1;
230 }
231
232 return 0;
233}
234
235/**
236 * Return the next keyscan message contents
237 *
238 * @param ec Current emulated EC state
239 * @param scan Place to put keyscan bytes for the keyscan message (must hold
240 * enough space for a full keyscan)
241 * @return number of bytes of valid scan data
242 */
243static int cros_ec_keyscan(struct ec_state *ec, uint8_t *scan)
244{
245 const struct ec_keymatrix_entry *matrix;
246 int bytes = KEYBOARD_COLS;
247 int key[8]; /* allow up to 8 keys to be pressed at once */
248 int count;
249 int i;
250
251 memset(ec->keyscan, '\0', bytes);
252 count = sandbox_sdl_scan_keys(key, ARRAY_SIZE(key));
253
254 /* Look up keycode in matrix */
255 for (i = 0, matrix = ec->matrix; i < ec->matrix_count; i++, matrix++) {
256 bool found;
257 int j;
258
259 for (found = false, j = 0; j < count; j++) {
260 if (matrix->keycode == key[j])
261 found = true;
262 }
263
264 if (found) {
265 debug("%d: %d,%d\n", matrix->keycode, matrix->row,
266 matrix->col);
267 ec->keyscan[matrix->col] |= 1 << matrix->row;
268 }
269 }
270
271 memcpy(scan, ec->keyscan, bytes);
272 return bytes;
273}
274
275/**
276 * Process an emulated EC command
277 *
278 * @param ec Current emulated EC state
279 * @param req_hdr Pointer to request header
280 * @param req_data Pointer to body of request
281 * @param resp_hdr Pointer to place to put response header
282 * @param resp_data Pointer to place to put response data, if any
283 * @return length of response data, or 0 for no response data, or -1 on error
284 */
285static int process_cmd(struct ec_state *ec,
286 struct ec_host_request *req_hdr, const void *req_data,
287 struct ec_host_response *resp_hdr, void *resp_data)
288{
289 int len;
290
291 /* TODO(sjg@chromium.org): Check checksums */
292 debug("EC command %#0x\n", req_hdr->command);
293
294 switch (req_hdr->command) {
295 case EC_CMD_HELLO: {
296 const struct ec_params_hello *req = req_data;
297 struct ec_response_hello *resp = resp_data;
298
299 resp->out_data = req->in_data + 0x01020304;
300 len = sizeof(*resp);
301 break;
302 }
303 case EC_CMD_GET_VERSION: {
304 struct ec_response_get_version *resp = resp_data;
305
306 strcpy(resp->version_string_ro, "sandbox_ro");
307 strcpy(resp->version_string_rw, "sandbox_rw");
308 resp->current_image = ec->current_image;
309 debug("Current image %d\n", resp->current_image);
310 len = sizeof(*resp);
311 break;
312 }
313 case EC_CMD_VBNV_CONTEXT: {
314 const struct ec_params_vbnvcontext *req = req_data;
315 struct ec_response_vbnvcontext *resp = resp_data;
316
317 switch (req->op) {
318 case EC_VBNV_CONTEXT_OP_READ:
319 memcpy(resp->block, ec->vbnv_context,
320 sizeof(resp->block));
321 len = sizeof(*resp);
322 break;
323 case EC_VBNV_CONTEXT_OP_WRITE:
324 memcpy(ec->vbnv_context, resp->block,
325 sizeof(resp->block));
326 len = 0;
327 break;
328 default:
329 printf(" ** Unknown vbnv_context command %#02x\n",
330 req->op);
331 return -1;
332 }
333 break;
334 }
335 case EC_CMD_REBOOT_EC: {
336 const struct ec_params_reboot_ec *req = req_data;
337
338 printf("Request reboot type %d\n", req->cmd);
339 switch (req->cmd) {
340 case EC_REBOOT_DISABLE_JUMP:
341 len = 0;
342 break;
343 case EC_REBOOT_JUMP_RW:
344 ec->current_image = EC_IMAGE_RW;
345 len = 0;
346 break;
347 default:
348 puts(" ** Unknown type");
349 return -1;
350 }
351 break;
352 }
353 case EC_CMD_HOST_EVENT_GET_B: {
354 struct ec_response_host_event_mask *resp = resp_data;
355
356 resp->mask = 0;
357 if (ec->recovery_req) {
358 resp->mask |= EC_HOST_EVENT_MASK(
359 EC_HOST_EVENT_KEYBOARD_RECOVERY);
360 }
361
362 len = sizeof(*resp);
363 break;
364 }
365 case EC_CMD_VBOOT_HASH: {
366 const struct ec_params_vboot_hash *req = req_data;
367 struct ec_response_vboot_hash *resp = resp_data;
368 struct fmap_entry *entry;
369 int ret, size;
370
Simon Glassbe995a82014-10-13 23:42:15 -0600371 entry = &ec->ec_config.region[EC_FLASH_REGION_RW];
Simon Glassdf93d902014-02-27 13:26:12 -0700372
373 switch (req->cmd) {
374 case EC_VBOOT_HASH_RECALC:
375 case EC_VBOOT_HASH_GET:
376 size = SHA256_SUM_LEN;
377 len = get_image_used(ec, entry);
378 ret = hash_block("sha256",
379 ec->flash_data + entry->offset,
380 len, resp->hash_digest, &size);
381 if (ret) {
382 printf(" ** hash_block() failed\n");
383 return -1;
384 }
385 resp->status = EC_VBOOT_HASH_STATUS_DONE;
386 resp->hash_type = EC_VBOOT_HASH_TYPE_SHA256;
387 resp->digest_size = size;
388 resp->reserved0 = 0;
389 resp->offset = entry->offset;
390 resp->size = len;
391 len = sizeof(*resp);
392 break;
393 default:
394 printf(" ** EC_CMD_VBOOT_HASH: Unknown command %d\n",
395 req->cmd);
396 return -1;
397 }
398 break;
399 }
400 case EC_CMD_FLASH_PROTECT: {
401 const struct ec_params_flash_protect *req = req_data;
402 struct ec_response_flash_protect *resp = resp_data;
403 uint32_t expect = EC_FLASH_PROTECT_ALL_NOW |
404 EC_FLASH_PROTECT_ALL_AT_BOOT;
405
406 printf("mask=%#x, flags=%#x\n", req->mask, req->flags);
407 if (req->flags == expect || req->flags == 0) {
408 resp->flags = req->flags ? EC_FLASH_PROTECT_ALL_NOW :
409 0;
410 resp->valid_flags = EC_FLASH_PROTECT_ALL_NOW;
411 resp->writable_flags = 0;
412 len = sizeof(*resp);
413 } else {
414 puts(" ** unexpected flash protect request\n");
415 return -1;
416 }
417 break;
418 }
419 case EC_CMD_FLASH_REGION_INFO: {
420 const struct ec_params_flash_region_info *req = req_data;
421 struct ec_response_flash_region_info *resp = resp_data;
422 struct fmap_entry *entry;
423
424 switch (req->region) {
425 case EC_FLASH_REGION_RO:
426 case EC_FLASH_REGION_RW:
427 case EC_FLASH_REGION_WP_RO:
Simon Glassbe995a82014-10-13 23:42:15 -0600428 entry = &ec->ec_config.region[req->region];
Simon Glassdf93d902014-02-27 13:26:12 -0700429 resp->offset = entry->offset;
430 resp->size = entry->length;
431 len = sizeof(*resp);
432 printf("EC flash region %d: offset=%#x, size=%#x\n",
433 req->region, resp->offset, resp->size);
434 break;
435 default:
436 printf("** Unknown flash region %d\n", req->region);
437 return -1;
438 }
439 break;
440 }
441 case EC_CMD_FLASH_ERASE: {
442 const struct ec_params_flash_erase *req = req_data;
443
444 memset(ec->flash_data + req->offset,
445 ec->ec_config.flash_erase_value,
446 req->size);
447 len = 0;
448 break;
449 }
450 case EC_CMD_FLASH_WRITE: {
451 const struct ec_params_flash_write *req = req_data;
452
453 memcpy(ec->flash_data + req->offset, req + 1, req->size);
454 len = 0;
455 break;
456 }
457 case EC_CMD_MKBP_STATE:
458 len = cros_ec_keyscan(ec, resp_data);
459 break;
Simon Glassb5279242015-05-04 11:31:09 -0600460 case EC_CMD_ENTERING_MODE:
Daniel Schwierzeck3f51a772015-11-06 14:15:37 +0100461 len = 0;
Simon Glassb5279242015-05-04 11:31:09 -0600462 break;
Simon Glassdf93d902014-02-27 13:26:12 -0700463 default:
464 printf(" ** Unknown EC command %#02x\n", req_hdr->command);
465 return -1;
466 }
467
468 return len;
469}
470
Simon Glassbe995a82014-10-13 23:42:15 -0600471int cros_ec_sandbox_packet(struct udevice *udev, int out_bytes, int in_bytes)
472{
Simon Glasse564f052015-03-05 12:25:20 -0700473 struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
Simon Glassbe995a82014-10-13 23:42:15 -0600474 struct ec_state *ec = dev_get_priv(dev->dev);
Simon Glassdf93d902014-02-27 13:26:12 -0700475 struct ec_host_request *req_hdr = (struct ec_host_request *)dev->dout;
476 const void *req_data = req_hdr + 1;
477 struct ec_host_response *resp_hdr = (struct ec_host_response *)dev->din;
478 void *resp_data = resp_hdr + 1;
479 int len;
480
Simon Glassbe995a82014-10-13 23:42:15 -0600481 len = process_cmd(ec, req_hdr, req_data, resp_hdr, resp_data);
Simon Glassdf93d902014-02-27 13:26:12 -0700482 if (len < 0)
483 return len;
484
485 resp_hdr->struct_version = 3;
486 resp_hdr->result = EC_RES_SUCCESS;
487 resp_hdr->data_len = len;
488 resp_hdr->reserved = 0;
489 len += sizeof(*resp_hdr);
490 resp_hdr->checksum = 0;
491 resp_hdr->checksum = (uint8_t)
492 -cros_ec_calc_checksum((const uint8_t *)resp_hdr, len);
493
494 return in_bytes;
495}
496
Simon Glassdf93d902014-02-27 13:26:12 -0700497void cros_ec_check_keyboard(struct cros_ec_dev *dev)
498{
Simon Glassbe995a82014-10-13 23:42:15 -0600499 struct ec_state *ec = dev_get_priv(dev->dev);
Simon Glassdf93d902014-02-27 13:26:12 -0700500 ulong start;
501
502 printf("Press keys for EC to detect on reset (ESC=recovery)...");
503 start = get_timer(0);
504 while (get_timer(start) < 1000)
505 ;
506 putc('\n');
507 if (!sandbox_sdl_key_pressed(KEY_ESC)) {
508 ec->recovery_req = true;
509 printf(" - EC requests recovery\n");
510 }
511}
512
Simon Glassbe995a82014-10-13 23:42:15 -0600513int cros_ec_probe(struct udevice *dev)
514{
515 struct ec_state *ec = dev->priv;
516 struct cros_ec_dev *cdev = dev->uclass_priv;
Simon Glass920c6962016-06-19 17:33:15 -0600517 struct udevice *keyb_dev;
Simon Glass2ec9d172017-05-18 20:09:23 -0600518 ofnode node;
Simon Glassbe995a82014-10-13 23:42:15 -0600519 int err;
520
521 memcpy(ec, &s_state, sizeof(*ec));
Simon Glass2ec9d172017-05-18 20:09:23 -0600522 err = cros_ec_decode_ec_flash(dev, &ec->ec_config);
523 if (err) {
524 debug("%s: Cannot device EC flash\n", __func__);
Simon Glassbe995a82014-10-13 23:42:15 -0600525 return err;
Simon Glass2ec9d172017-05-18 20:09:23 -0600526 }
Simon Glassbe995a82014-10-13 23:42:15 -0600527
Simon Glass2ec9d172017-05-18 20:09:23 -0600528 node = ofnode_null();
Simon Glass920c6962016-06-19 17:33:15 -0600529 for (device_find_first_child(dev, &keyb_dev);
530 keyb_dev;
531 device_find_next_child(&keyb_dev)) {
532 if (device_get_uclass_id(keyb_dev) == UCLASS_KEYBOARD) {
Simon Glass2ec9d172017-05-18 20:09:23 -0600533 node = dev_ofnode(keyb_dev);
Simon Glass920c6962016-06-19 17:33:15 -0600534 break;
535 }
536 }
Simon Glass2ec9d172017-05-18 20:09:23 -0600537 if (!ofnode_valid(node)) {
Simon Glassbe995a82014-10-13 23:42:15 -0600538 debug("%s: No cros_ec keyboard found\n", __func__);
Simon Glass2ec9d172017-05-18 20:09:23 -0600539 } else if (keyscan_read_fdt_matrix(ec, node)) {
Simon Glassbe995a82014-10-13 23:42:15 -0600540 debug("%s: Could not read key matrix\n", __func__);
541 return -1;
542 }
543
544 /* If we loaded EC data, check that the length matches */
545 if (ec->flash_data &&
546 ec->flash_data_len != ec->ec_config.flash.length) {
547 printf("EC data length is %x, expected %x, discarding data\n",
548 ec->flash_data_len, ec->ec_config.flash.length);
549 os_free(ec->flash_data);
550 ec->flash_data = NULL;
551 }
552
553 /* Otherwise allocate the memory */
554 if (!ec->flash_data) {
555 ec->flash_data_len = ec->ec_config.flash.length;
556 ec->flash_data = os_malloc(ec->flash_data_len);
557 if (!ec->flash_data)
558 return -ENOMEM;
559 }
560
561 cdev->dev = dev;
562 g_state = ec;
563 return cros_ec_register(dev);
564}
565
Simon Glassbe995a82014-10-13 23:42:15 -0600566struct dm_cros_ec_ops cros_ec_ops = {
567 .packet = cros_ec_sandbox_packet,
568};
569
570static const struct udevice_id cros_ec_ids[] = {
Simon Glass3fbb7872015-03-26 09:29:39 -0600571 { .compatible = "google,cros-ec-sandbox" },
Simon Glassbe995a82014-10-13 23:42:15 -0600572 { }
573};
574
575U_BOOT_DRIVER(cros_ec_sandbox) = {
Simon Glass3fbb7872015-03-26 09:29:39 -0600576 .name = "cros_ec_sandbox",
Simon Glassbe995a82014-10-13 23:42:15 -0600577 .id = UCLASS_CROS_EC,
578 .of_match = cros_ec_ids,
579 .probe = cros_ec_probe,
580 .priv_auto_alloc_size = sizeof(struct ec_state),
581 .ops = &cros_ec_ops,
582};