1 // SPDX-License-Identifier: GPL-2.0+
3 * Chromium OS cros_ec driver - sandbox emulation
5 * Copyright (c) 2013 The Chromium OS Authors.
11 #include <ec_commands.h>
16 #include <u-boot/sha256.h>
18 #include <asm/malloc.h>
19 #include <asm/state.h>
22 #include <linux/input.h>
25 * Ultimately it shold be possible to connect an Chrome OS EC emulation
26 * to U-Boot and remove all of this code. But this provides a test
27 * environment for bringing up chromeos_sandbox and demonstrating its
30 * This emulation includes the following:
32 * 1. Emulation of the keyboard, by converting keypresses received from SDL
33 * into key scan data, passed back from the EC as key scan messages. The
34 * key layout is read from the device tree.
36 * 2. Emulation of vboot context - so this can be read/written as required.
38 * 3. Save/restore of EC state, so that the vboot context, flash memory
39 * contents and current image can be preserved across boots. This is important
40 * since the EC is supposed to continue running even if the AP resets.
42 * 4. Some event support, in particular allowing Escape to be pressed on boot
43 * to enter recovery mode. The EC passes this to U-Boot through the normal
46 * 5. Flash read/write/erase support, so that software sync works. The
47 * protect messages are supported but no protection is implemented.
49 * 6. Hashing of the EC image, again to support software sync.
51 * Other features can be added, although a better path is probably to link
52 * the EC image in with U-Boot (Vic has demonstrated a prototype for this).
55 #define KEYBOARD_ROWS 8
56 #define KEYBOARD_COLS 13
58 /* A single entry of the key matrix */
59 struct ec_keymatrix_entry {
60 int row; /* key matrix row */
61 int col; /* key matrix column */
62 int keycode; /* corresponding linux key code */
66 VSTORE_SLOT_COUNT = 4,
71 u8 data[EC_VSTORE_SLOT_SIZE];
75 * struct ec_state - Information about the EC state
77 * @vbnv_context: Vboot context data stored by EC
78 * @ec_config: FDT config information about the EC (e.g. flashmap)
79 * @flash_data: Contents of flash memory
80 * @flash_data_len: Size of flash memory
81 * @current_image: Current image the EC is running
82 * @matrix_count: Number of keys to decode in matrix
83 * @matrix: Information about keyboard matrix
84 * @keyscan: Current keyscan information (bit set for each row/column pressed)
85 * @recovery_req: Keyboard recovery requested
86 * @test_flags: Flags that control behaviour for tests
87 * @slot_locked: Locked vstore slots (mask)
90 u8 vbnv_context[EC_VBNV_BLOCK_SIZE_V2];
91 struct fdt_cros_ec ec_config;
94 enum ec_current_image current_image;
96 struct ec_keymatrix_entry *matrix; /* the key matrix info */
97 uint8_t keyscan[KEYBOARD_COLS];
100 struct vstore_slot slot[VSTORE_SLOT_COUNT];
104 * cros_ec_read_state() - read the sandbox EC state from the state file
106 * If data is available, then blob and node will provide access to it. If
107 * not this function sets up an empty EC.
109 * @param blob: Pointer to device tree blob, or NULL if no data to read
110 * @param node: Node offset to read from
112 static int cros_ec_read_state(const void *blob, int node)
114 struct ec_state *ec = &s_state;
118 /* Set everything to defaults */
119 ec->current_image = EC_IMAGE_RO;
123 /* Read the data if available */
124 ec->current_image = fdtdec_get_int(blob, node, "current-image",
126 prop = fdt_getprop(blob, node, "vbnv-context", &len);
127 if (prop && len == sizeof(ec->vbnv_context))
128 memcpy(ec->vbnv_context, prop, len);
130 prop = fdt_getprop(blob, node, "flash-data", &len);
132 ec->flash_data_len = len;
133 ec->flash_data = malloc(len);
136 memcpy(ec->flash_data, prop, len);
137 debug("%s: Loaded EC flash data size %#x\n", __func__, len);
144 * cros_ec_write_state() - Write out our state to the state file
146 * The caller will ensure that there is a node ready for the state. The node
147 * may already contain the old state, in which case it is overridden.
149 * @param blob: Device tree blob holding state
150 * @param node: Node to write our state into
152 static int cros_ec_write_state(void *blob, int node)
154 struct ec_state *ec = g_state;
159 /* We are guaranteed enough space to write basic properties */
160 fdt_setprop_u32(blob, node, "current-image", ec->current_image);
161 fdt_setprop(blob, node, "vbnv-context", ec->vbnv_context,
162 sizeof(ec->vbnv_context));
164 return state_setprop(node, "flash-data", ec->flash_data,
165 ec->ec_config.flash.length);
168 SANDBOX_STATE_IO(cros_ec, "google,cros-ec", cros_ec_read_state,
169 cros_ec_write_state);
172 * Return the number of bytes used in the specified image.
174 * This is the actual size of code+data in the image, as opposed to the
175 * amount of space reserved in flash for that image. This code is similar to
176 * that used by the real EC code base.
178 * @param ec Current emulated EC state
179 * @param entry Flash map entry containing the image to check
180 * @return actual image size in bytes, 0 if the image contains no content or
183 static int get_image_used(struct ec_state *ec, struct fmap_entry *entry)
188 * Scan backwards looking for 0xea byte, which is by definition the
189 * last byte of the image. See ec.lds.S for how this is inserted at
190 * the end of the image.
192 for (size = entry->length - 1;
193 size > 0 && ec->flash_data[entry->offset + size] != 0xea;
197 return size ? size + 1 : 0; /* 0xea byte IS part of the image */
201 * Read the key matrix from the device tree
203 * Keymap entries in the fdt take the form of 0xRRCCKKKK where
204 * RR=Row CC=Column KKKK=Key Code
206 * @param ec Current emulated EC state
207 * @param node Keyboard node of device tree containing keyscan information
208 * @return 0 if ok, -1 on error
210 static int keyscan_read_fdt_matrix(struct ec_state *ec, ofnode node)
216 cell = ofnode_get_property(node, "linux,keymap", &len);
217 ec->matrix_count = len / 4;
218 ec->matrix = calloc(ec->matrix_count, sizeof(*ec->matrix));
220 debug("%s: Out of memory for key matrix\n", __func__);
224 /* Now read the data */
225 for (upto = 0; upto < ec->matrix_count; upto++) {
226 struct ec_keymatrix_entry *matrix = &ec->matrix[upto];
229 word = fdt32_to_cpu(*cell++);
230 matrix->row = word >> 24;
231 matrix->col = (word >> 16) & 0xff;
232 matrix->keycode = word & 0xffff;
234 /* Hard-code some sanity limits for now */
235 if (matrix->row >= KEYBOARD_ROWS ||
236 matrix->col >= KEYBOARD_COLS) {
237 debug("%s: Matrix pos out of range (%d,%d)\n",
238 __func__, matrix->row, matrix->col);
243 if (upto != ec->matrix_count) {
244 debug("%s: Read mismatch from key matrix\n", __func__);
252 * Return the next keyscan message contents
254 * @param ec Current emulated EC state
255 * @param scan Place to put keyscan bytes for the keyscan message (must hold
256 * enough space for a full keyscan)
257 * @return number of bytes of valid scan data
259 static int cros_ec_keyscan(struct ec_state *ec, uint8_t *scan)
261 const struct ec_keymatrix_entry *matrix;
262 int bytes = KEYBOARD_COLS;
263 int key[8]; /* allow up to 8 keys to be pressed at once */
267 memset(ec->keyscan, '\0', bytes);
268 count = sandbox_sdl_scan_keys(key, ARRAY_SIZE(key));
270 /* Look up keycode in matrix */
271 for (i = 0, matrix = ec->matrix; i < ec->matrix_count; i++, matrix++) {
275 for (found = false, j = 0; j < count; j++) {
276 if (matrix->keycode == key[j])
281 debug("%d: %d,%d\n", matrix->keycode, matrix->row,
283 ec->keyscan[matrix->col] |= 1 << matrix->row;
287 memcpy(scan, ec->keyscan, bytes);
292 * Process an emulated EC command
294 * @param ec Current emulated EC state
295 * @param req_hdr Pointer to request header
296 * @param req_data Pointer to body of request
297 * @param resp_hdr Pointer to place to put response header
298 * @param resp_data Pointer to place to put response data, if any
299 * @return length of response data, or 0 for no response data, or -1 on error
301 static int process_cmd(struct ec_state *ec,
302 struct ec_host_request *req_hdr, const void *req_data,
303 struct ec_host_response *resp_hdr, void *resp_data)
307 /* TODO(sjg@chromium.org): Check checksums */
308 debug("EC command %#0x\n", req_hdr->command);
310 switch (req_hdr->command) {
312 const struct ec_params_hello *req = req_data;
313 struct ec_response_hello *resp = resp_data;
315 resp->out_data = req->in_data + 0x01020304;
316 if (ec->test_flags & CROSECT_BREAK_HELLO)
321 case EC_CMD_GET_VERSION: {
322 struct ec_response_get_version *resp = resp_data;
324 strcpy(resp->version_string_ro, "sandbox_ro");
325 strcpy(resp->version_string_rw, "sandbox_rw");
326 resp->current_image = ec->current_image;
327 debug("Current image %d\n", resp->current_image);
331 case EC_CMD_VBNV_CONTEXT: {
332 const struct ec_params_vbnvcontext *req = req_data;
333 struct ec_response_vbnvcontext *resp = resp_data;
336 case EC_VBNV_CONTEXT_OP_READ:
337 /* TODO(sjg@chromium.org): Support full-size context */
338 memcpy(resp->block, ec->vbnv_context,
342 case EC_VBNV_CONTEXT_OP_WRITE:
343 /* TODO(sjg@chromium.org): Support full-size context */
344 memcpy(ec->vbnv_context, req->block,
349 printf(" ** Unknown vbnv_context command %#02x\n",
355 case EC_CMD_REBOOT_EC: {
356 const struct ec_params_reboot_ec *req = req_data;
358 printf("Request reboot type %d\n", req->cmd);
360 case EC_REBOOT_DISABLE_JUMP:
363 case EC_REBOOT_JUMP_RW:
364 ec->current_image = EC_IMAGE_RW;
368 puts(" ** Unknown type");
373 case EC_CMD_HOST_EVENT_GET_B: {
374 struct ec_response_host_event_mask *resp = resp_data;
377 if (ec->recovery_req) {
378 resp->mask |= EC_HOST_EVENT_MASK(
379 EC_HOST_EVENT_KEYBOARD_RECOVERY);
381 if (ec->test_flags & CROSECT_LID_OPEN)
383 EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_OPEN);
387 case EC_CMD_HOST_EVENT_CLEAR_B: {
388 const struct ec_params_host_event_mask *req = req_data;
390 if (req->mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_OPEN))
391 ec->test_flags &= ~CROSECT_LID_OPEN;
395 case EC_CMD_VBOOT_HASH: {
396 const struct ec_params_vboot_hash *req = req_data;
397 struct ec_response_vboot_hash *resp = resp_data;
398 struct fmap_entry *entry;
401 entry = &ec->ec_config.region[EC_FLASH_REGION_ACTIVE];
404 case EC_VBOOT_HASH_RECALC:
405 case EC_VBOOT_HASH_GET:
406 size = SHA256_SUM_LEN;
407 len = get_image_used(ec, entry);
408 ret = hash_block("sha256",
409 ec->flash_data + entry->offset,
410 len, resp->hash_digest, &size);
412 printf(" ** hash_block() failed\n");
415 resp->status = EC_VBOOT_HASH_STATUS_DONE;
416 resp->hash_type = EC_VBOOT_HASH_TYPE_SHA256;
417 resp->digest_size = size;
419 resp->offset = entry->offset;
424 printf(" ** EC_CMD_VBOOT_HASH: Unknown command %d\n",
430 case EC_CMD_FLASH_PROTECT: {
431 const struct ec_params_flash_protect *req = req_data;
432 struct ec_response_flash_protect *resp = resp_data;
433 uint32_t expect = EC_FLASH_PROTECT_ALL_NOW |
434 EC_FLASH_PROTECT_ALL_AT_BOOT;
436 printf("mask=%#x, flags=%#x\n", req->mask, req->flags);
437 if (req->flags == expect || req->flags == 0) {
438 resp->flags = req->flags ? EC_FLASH_PROTECT_ALL_NOW :
440 resp->valid_flags = EC_FLASH_PROTECT_ALL_NOW;
441 resp->writable_flags = 0;
444 puts(" ** unexpected flash protect request\n");
449 case EC_CMD_FLASH_REGION_INFO: {
450 const struct ec_params_flash_region_info *req = req_data;
451 struct ec_response_flash_region_info *resp = resp_data;
452 struct fmap_entry *entry;
454 switch (req->region) {
455 case EC_FLASH_REGION_RO:
456 case EC_FLASH_REGION_ACTIVE:
457 case EC_FLASH_REGION_WP_RO:
458 entry = &ec->ec_config.region[req->region];
459 resp->offset = entry->offset;
460 resp->size = entry->length;
462 printf("EC flash region %d: offset=%#x, size=%#x\n",
463 req->region, resp->offset, resp->size);
466 printf("** Unknown flash region %d\n", req->region);
471 case EC_CMD_FLASH_ERASE: {
472 const struct ec_params_flash_erase *req = req_data;
474 memset(ec->flash_data + req->offset,
475 ec->ec_config.flash_erase_value,
480 case EC_CMD_FLASH_WRITE: {
481 const struct ec_params_flash_write *req = req_data;
483 memcpy(ec->flash_data + req->offset, req + 1, req->size);
487 case EC_CMD_MKBP_STATE:
488 len = cros_ec_keyscan(ec, resp_data);
490 case EC_CMD_ENTERING_MODE:
493 case EC_CMD_GET_NEXT_EVENT: {
494 struct ec_response_get_next_event *resp = resp_data;
496 resp->event_type = EC_MKBP_EVENT_KEY_MATRIX;
497 cros_ec_keyscan(ec, resp->data.key_matrix);
501 case EC_CMD_GET_SKU_ID: {
502 struct ec_sku_id_info *resp = resp_data;
508 case EC_CMD_GET_FEATURES: {
509 struct ec_response_get_features *resp = resp_data;
511 resp->flags[0] = EC_FEATURE_MASK_0(EC_FEATURE_FLASH) |
512 EC_FEATURE_MASK_0(EC_FEATURE_I2C) |
513 EC_FEATURE_MASK_0(EC_FEATURE_VSTORE);
515 EC_FEATURE_MASK_1(EC_FEATURE_UNIFIED_WAKE_MASKS) |
516 EC_FEATURE_MASK_1(EC_FEATURE_ISH);
520 case EC_CMD_VSTORE_INFO: {
521 struct ec_response_vstore_info *resp = resp_data;
524 resp->slot_count = VSTORE_SLOT_COUNT;
525 resp->slot_locked = 0;
526 for (i = 0; i < VSTORE_SLOT_COUNT; i++) {
527 if (ec->slot[i].locked)
528 resp->slot_locked |= 1 << i;
533 case EC_CMD_VSTORE_WRITE: {
534 const struct ec_params_vstore_write *req = req_data;
535 struct vstore_slot *slot;
537 if (req->slot >= EC_VSTORE_SLOT_MAX)
539 slot = &ec->slot[req->slot];
541 memcpy(slot->data, req->data, EC_VSTORE_SLOT_SIZE);
545 case EC_CMD_VSTORE_READ: {
546 const struct ec_params_vstore_read *req = req_data;
547 struct ec_response_vstore_read *resp = resp_data;
548 struct vstore_slot *slot;
550 if (req->slot >= EC_VSTORE_SLOT_MAX)
552 slot = &ec->slot[req->slot];
553 memcpy(resp->data, slot->data, EC_VSTORE_SLOT_SIZE);
558 printf(" ** Unknown EC command %#02x\n", req_hdr->command);
565 int cros_ec_sandbox_packet(struct udevice *udev, int out_bytes, int in_bytes)
567 struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
568 struct ec_state *ec = dev_get_priv(dev->dev);
569 struct ec_host_request *req_hdr = (struct ec_host_request *)dev->dout;
570 const void *req_data = req_hdr + 1;
571 struct ec_host_response *resp_hdr = (struct ec_host_response *)dev->din;
572 void *resp_data = resp_hdr + 1;
575 len = process_cmd(ec, req_hdr, req_data, resp_hdr, resp_data);
579 resp_hdr->struct_version = 3;
580 resp_hdr->result = EC_RES_SUCCESS;
581 resp_hdr->data_len = len;
582 resp_hdr->reserved = 0;
583 len += sizeof(*resp_hdr);
584 resp_hdr->checksum = 0;
585 resp_hdr->checksum = (uint8_t)
586 -cros_ec_calc_checksum((const uint8_t *)resp_hdr, len);
591 void cros_ec_check_keyboard(struct udevice *dev)
593 struct ec_state *ec = dev_get_priv(dev);
596 printf("Press keys for EC to detect on reset (ESC=recovery)...");
597 start = get_timer(0);
598 while (get_timer(start) < 1000)
601 if (!sandbox_sdl_key_pressed(KEY_ESC)) {
602 ec->recovery_req = true;
603 printf(" - EC requests recovery\n");
607 /* Return the byte of EC switch states */
608 static int cros_ec_sandbox_get_switches(struct udevice *dev)
610 struct ec_state *ec = dev_get_priv(dev);
612 return ec->test_flags & CROSECT_LID_OPEN ? EC_SWITCH_LID_OPEN : 0;
615 void sandbox_cros_ec_set_test_flags(struct udevice *dev, uint flags)
617 struct ec_state *ec = dev_get_priv(dev);
619 ec->test_flags = flags;
622 int cros_ec_probe(struct udevice *dev)
624 struct ec_state *ec = dev_get_priv(dev);
625 struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
626 struct udevice *keyb_dev;
630 memcpy(ec, &s_state, sizeof(*ec));
631 err = cros_ec_decode_ec_flash(dev, &ec->ec_config);
633 debug("%s: Cannot device EC flash\n", __func__);
637 node = ofnode_null();
638 for (device_find_first_child(dev, &keyb_dev);
640 device_find_next_child(&keyb_dev)) {
641 if (device_get_uclass_id(keyb_dev) == UCLASS_KEYBOARD) {
642 node = dev_ofnode(keyb_dev);
646 if (!ofnode_valid(node)) {
647 debug("%s: No cros_ec keyboard found\n", __func__);
648 } else if (keyscan_read_fdt_matrix(ec, node)) {
649 debug("%s: Could not read key matrix\n", __func__);
653 /* If we loaded EC data, check that the length matches */
654 if (ec->flash_data &&
655 ec->flash_data_len != ec->ec_config.flash.length) {
656 printf("EC data length is %x, expected %x, discarding data\n",
657 ec->flash_data_len, ec->ec_config.flash.length);
658 free(ec->flash_data);
659 ec->flash_data = NULL;
662 /* Otherwise allocate the memory */
663 if (!ec->flash_data) {
664 ec->flash_data_len = ec->ec_config.flash.length;
665 ec->flash_data = malloc(ec->flash_data_len);
672 return cros_ec_register(dev);
675 struct dm_cros_ec_ops cros_ec_ops = {
676 .packet = cros_ec_sandbox_packet,
677 .get_switches = cros_ec_sandbox_get_switches,
680 static const struct udevice_id cros_ec_ids[] = {
681 { .compatible = "google,cros-ec-sandbox" },
685 U_BOOT_DRIVER(google_cros_ec_sandbox) = {
686 .name = "google_cros_ec_sandbox",
687 .id = UCLASS_CROS_EC,
688 .of_match = cros_ec_ids,
689 .probe = cros_ec_probe,
690 .priv_auto = sizeof(struct ec_state),