xref: /linux/drivers/net/wireless/silabs/wfx/fwio.c (revision d30aca3eeffc18452e5cc5c4e59f1a4da2bd2f12)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Firmware loading.
4  *
5  * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
6  * Copyright (c) 2010, ST-Ericsson
7  */
8 #include <linux/firmware.h>
9 #include <linux/hex.h>
10 #include <linux/slab.h>
11 #include <linux/mm.h>
12 #include <linux/bitfield.h>
13 
14 #include "fwio.h"
15 #include "wfx.h"
16 #include "hwio.h"
17 
18 /* Addresses below are in SRAM area */
19 #define WFX_DNLD_FIFO             0x09004000
20 #define     DNLD_BLOCK_SIZE           0x0400
21 #define     DNLD_FIFO_SIZE            0x8000 /* (32 * DNLD_BLOCK_SIZE) */
22 /* Download Control Area (DCA) */
23 #define WFX_DCA_IMAGE_SIZE        0x0900C000
24 #define WFX_DCA_PUT               0x0900C004
25 #define WFX_DCA_GET               0x0900C008
26 #define WFX_DCA_HOST_STATUS       0x0900C00C
27 #define     HOST_READY                0x87654321
28 #define     HOST_INFO_READ            0xA753BD99
29 #define     HOST_UPLOAD_PENDING       0xABCDDCBA
30 #define     HOST_UPLOAD_COMPLETE      0xD4C64A99
31 #define     HOST_OK_TO_JUMP           0x174FC882
32 #define WFX_DCA_NCP_STATUS        0x0900C010
33 #define     NCP_NOT_READY             0x12345678
34 #define     NCP_READY                 0x87654321
35 #define     NCP_INFO_READY            0xBD53EF99
36 #define     NCP_DOWNLOAD_PENDING      0xABCDDCBA
37 #define     NCP_DOWNLOAD_COMPLETE     0xCAFEFECA
38 #define     NCP_AUTH_OK               0xD4C64A99
39 #define     NCP_AUTH_FAIL             0x174FC882
40 #define     NCP_PUB_KEY_RDY           0x7AB41D19
41 #define WFX_DCA_FW_SIGNATURE      0x0900C014
42 #define     FW_SIGNATURE_SIZE         0x40
43 #define WFX_DCA_FW_HASH           0x0900C054
44 #define     FW_HASH_SIZE              0x08
45 #define WFX_DCA_FW_VERSION        0x0900C05C
46 #define     FW_VERSION_SIZE           0x04
47 #define WFX_DCA_RESERVED          0x0900C060
48 #define     DCA_RESERVED_SIZE         0x20
49 #define WFX_STATUS_INFO           0x0900C080
50 #define WFX_BOOTLOADER_LABEL      0x0900C084
51 #define     BOOTLOADER_LABEL_SIZE     0x3C
52 #define WFX_PTE_INFO              0x0900C0C0
53 #define     PTE_INFO_KEYSET_IDX       0x0D
54 #define     PTE_INFO_SIZE             0x10
55 #define WFX_ERR_INFO              0x0900C0D0
56 #define     ERR_INVALID_SEC_TYPE      0x05
57 #define     ERR_SIG_VERIF_FAILED      0x0F
58 #define     ERR_AES_CTRL_KEY          0x10
59 #define     ERR_ECC_PUB_KEY           0x11
60 #define     ERR_MAC_KEY               0x18
61 
62 #define DCA_TIMEOUT  50 /* milliseconds */
63 #define WAKEUP_TIMEOUT 200 /* milliseconds */
64 
65 static const char * const fwio_errors[] = {
66 	[ERR_INVALID_SEC_TYPE] = "Invalid section type or wrong encryption",
67 	[ERR_SIG_VERIF_FAILED] = "Signature verification failed",
68 	[ERR_AES_CTRL_KEY]     = "AES control key not initialized",
69 	[ERR_ECC_PUB_KEY]      = "ECC public key not initialized",
70 	[ERR_MAC_KEY]          = "MAC key not initialized",
71 };
72 
73 /* request_firmware() allocate data using vmalloc(). It is not compatible with underlying hardware
74  * that use DMA. Function below detect this case and allocate a bounce buffer if necessary.
75  *
76  * Notice that, in doubt, you can enable CONFIG_DEBUG_SG to ask kernel to detect this problem at
77  * runtime  (else, kernel silently fail).
78  *
79  * NOTE: it may also be possible to use 'pages' from struct firmware and avoid bounce buffer
80  */
81 static int wfx_sram_write_dma_safe(struct wfx_dev *wdev, u32 addr, const u8 *buf, size_t len)
82 {
83 	int ret;
84 	const u8 *tmp;
85 
86 	if (!virt_addr_valid(buf)) {
87 		tmp = kmemdup(buf, len, GFP_KERNEL);
88 		if (!tmp)
89 			return -ENOMEM;
90 	} else {
91 		tmp = buf;
92 	}
93 	ret = wfx_sram_buf_write(wdev, addr, tmp, len);
94 	if (tmp != buf)
95 		kfree(tmp);
96 	return ret;
97 }
98 
99 static int get_firmware(struct wfx_dev *wdev, u32 keyset_chip,
100 			const struct firmware **fw, int *file_offset)
101 {
102 	int keyset_file;
103 	char filename[256];
104 	const char *data;
105 	int ret;
106 
107 	snprintf(filename, sizeof(filename), "%s_%02X.sec",
108 		 wdev->pdata.file_fw, keyset_chip);
109 	ret = firmware_request_nowarn(fw, filename, wdev->dev);
110 	if (ret) {
111 		dev_info(wdev->dev, "can't load %s, falling back to %s.sec\n",
112 			 filename, wdev->pdata.file_fw);
113 		snprintf(filename, sizeof(filename), "%s.sec", wdev->pdata.file_fw);
114 		ret = request_firmware(fw, filename, wdev->dev);
115 		if (ret) {
116 			dev_err(wdev->dev, "can't load %s\n", filename);
117 			*fw = NULL;
118 			return ret;
119 		}
120 	}
121 
122 	data = (*fw)->data;
123 	if (memcmp(data, "KEYSET", 6) != 0) {
124 		/* Legacy firmware format */
125 		*file_offset = 0;
126 		keyset_file = 0x90;
127 	} else {
128 		*file_offset = 8;
129 		keyset_file = (hex_to_bin(data[6]) * 16) | hex_to_bin(data[7]);
130 		if (keyset_file < 0) {
131 			dev_err(wdev->dev, "%s corrupted\n", filename);
132 			release_firmware(*fw);
133 			*fw = NULL;
134 			return -EINVAL;
135 		}
136 	}
137 	if (keyset_file != keyset_chip) {
138 		dev_err(wdev->dev, "firmware keyset is incompatible with chip (file: 0x%02X, chip: 0x%02X)\n",
139 			keyset_file, keyset_chip);
140 		release_firmware(*fw);
141 		*fw = NULL;
142 		return -ENODEV;
143 	}
144 	wdev->keyset = keyset_file;
145 	return 0;
146 }
147 
148 static int wait_ncp_status(struct wfx_dev *wdev, u32 status)
149 {
150 	ktime_t now, start;
151 	u32 reg;
152 	int ret;
153 
154 	start = ktime_get();
155 	for (;;) {
156 		ret = wfx_sram_reg_read(wdev, WFX_DCA_NCP_STATUS, &reg);
157 		if (ret < 0)
158 			return -EIO;
159 		now = ktime_get();
160 		if (reg == status)
161 			break;
162 		if (ktime_after(now, ktime_add_ms(start, DCA_TIMEOUT)))
163 			return -ETIMEDOUT;
164 	}
165 	if (ktime_compare(now, start))
166 		dev_dbg(wdev->dev, "chip answer after %lldus\n", ktime_us_delta(now, start));
167 	else
168 		dev_dbg(wdev->dev, "chip answer immediately\n");
169 	return 0;
170 }
171 
172 static int upload_firmware(struct wfx_dev *wdev, const u8 *data, size_t len)
173 {
174 	int ret;
175 	u32 offs, bytes_done = 0;
176 	ktime_t now, start;
177 
178 	if (len % DNLD_BLOCK_SIZE) {
179 		dev_err(wdev->dev, "firmware size is not aligned. Buffer overrun will occur\n");
180 		return -EIO;
181 	}
182 	offs = 0;
183 	while (offs < len) {
184 		start = ktime_get();
185 		for (;;) {
186 			now = ktime_get();
187 			if (offs + DNLD_BLOCK_SIZE - bytes_done < DNLD_FIFO_SIZE)
188 				break;
189 			if (ktime_after(now, ktime_add_ms(start, DCA_TIMEOUT)))
190 				return -ETIMEDOUT;
191 			ret = wfx_sram_reg_read(wdev, WFX_DCA_GET, &bytes_done);
192 			if (ret < 0)
193 				return ret;
194 		}
195 		if (ktime_compare(now, start))
196 			dev_dbg(wdev->dev, "answer after %lldus\n", ktime_us_delta(now, start));
197 
198 		ret = wfx_sram_write_dma_safe(wdev, WFX_DNLD_FIFO + (offs % DNLD_FIFO_SIZE),
199 					      data + offs, DNLD_BLOCK_SIZE);
200 		if (ret < 0)
201 			return ret;
202 
203 		/* The device seems to not support writing 0 in this register during first loop */
204 		offs += DNLD_BLOCK_SIZE;
205 		ret = wfx_sram_reg_write(wdev, WFX_DCA_PUT, offs);
206 		if (ret < 0)
207 			return ret;
208 	}
209 	return 0;
210 }
211 
212 static void print_boot_status(struct wfx_dev *wdev)
213 {
214 	u32 reg;
215 
216 	wfx_sram_reg_read(wdev, WFX_STATUS_INFO, &reg);
217 	if (reg == 0x12345678)
218 		return;
219 	wfx_sram_reg_read(wdev, WFX_ERR_INFO, &reg);
220 	if (reg < ARRAY_SIZE(fwio_errors) && fwio_errors[reg])
221 		dev_info(wdev->dev, "secure boot: %s\n", fwio_errors[reg]);
222 	else
223 		dev_info(wdev->dev, "secure boot: Error %#02x\n", reg);
224 }
225 
226 static int load_firmware_secure(struct wfx_dev *wdev)
227 {
228 	const struct firmware *fw = NULL;
229 	int header_size;
230 	int fw_offset;
231 	ktime_t start;
232 	u8 *buf;
233 	int ret;
234 
235 	BUILD_BUG_ON(PTE_INFO_SIZE > BOOTLOADER_LABEL_SIZE);
236 	buf = kmalloc(BOOTLOADER_LABEL_SIZE + 1, GFP_KERNEL);
237 	if (!buf)
238 		return -ENOMEM;
239 
240 	wfx_sram_reg_write(wdev, WFX_DCA_HOST_STATUS, HOST_READY);
241 	ret = wait_ncp_status(wdev, NCP_INFO_READY);
242 	if (ret)
243 		goto error;
244 
245 	wfx_sram_buf_read(wdev, WFX_BOOTLOADER_LABEL, buf, BOOTLOADER_LABEL_SIZE);
246 	buf[BOOTLOADER_LABEL_SIZE] = 0;
247 	dev_dbg(wdev->dev, "bootloader: \"%s\"\n", buf);
248 
249 	wfx_sram_buf_read(wdev, WFX_PTE_INFO, buf, PTE_INFO_SIZE);
250 	ret = get_firmware(wdev, buf[PTE_INFO_KEYSET_IDX], &fw, &fw_offset);
251 	if (ret)
252 		goto error;
253 	header_size = fw_offset + FW_SIGNATURE_SIZE + FW_HASH_SIZE;
254 
255 	wfx_sram_reg_write(wdev, WFX_DCA_HOST_STATUS, HOST_INFO_READ);
256 	ret = wait_ncp_status(wdev, NCP_READY);
257 	if (ret)
258 		goto error;
259 
260 	wfx_sram_reg_write(wdev, WFX_DNLD_FIFO, 0xFFFFFFFF); /* Fifo init */
261 	wfx_sram_write_dma_safe(wdev, WFX_DCA_FW_VERSION, "\x01\x00\x00\x00", FW_VERSION_SIZE);
262 	wfx_sram_write_dma_safe(wdev, WFX_DCA_FW_SIGNATURE, fw->data + fw_offset,
263 				FW_SIGNATURE_SIZE);
264 	wfx_sram_write_dma_safe(wdev, WFX_DCA_FW_HASH, fw->data + fw_offset + FW_SIGNATURE_SIZE,
265 				FW_HASH_SIZE);
266 	wfx_sram_reg_write(wdev, WFX_DCA_IMAGE_SIZE, fw->size - header_size);
267 	wfx_sram_reg_write(wdev, WFX_DCA_HOST_STATUS, HOST_UPLOAD_PENDING);
268 	ret = wait_ncp_status(wdev, NCP_DOWNLOAD_PENDING);
269 	if (ret)
270 		goto error;
271 
272 	start = ktime_get();
273 	ret = upload_firmware(wdev, fw->data + header_size, fw->size - header_size);
274 	if (ret)
275 		goto error;
276 	dev_dbg(wdev->dev, "firmware load after %lldus\n",
277 		ktime_us_delta(ktime_get(), start));
278 
279 	wfx_sram_reg_write(wdev, WFX_DCA_HOST_STATUS, HOST_UPLOAD_COMPLETE);
280 	ret = wait_ncp_status(wdev, NCP_AUTH_OK);
281 	/* Legacy ROM support */
282 	if (ret < 0)
283 		ret = wait_ncp_status(wdev, NCP_PUB_KEY_RDY);
284 	if (ret < 0)
285 		goto error;
286 	wfx_sram_reg_write(wdev, WFX_DCA_HOST_STATUS, HOST_OK_TO_JUMP);
287 
288 error:
289 	kfree(buf);
290 	release_firmware(fw);
291 	if (ret)
292 		print_boot_status(wdev);
293 	return ret;
294 }
295 
296 static int init_gpr(struct wfx_dev *wdev)
297 {
298 	int ret, i;
299 	static const struct {
300 		int index;
301 		u32 value;
302 	} gpr_init[] = {
303 		{ 0x07, 0x208775 },
304 		{ 0x08, 0x2EC020 },
305 		{ 0x09, 0x3C3C3C },
306 		{ 0x0B, 0x322C44 },
307 		{ 0x0C, 0xA06497 },
308 	};
309 
310 	for (i = 0; i < ARRAY_SIZE(gpr_init); i++) {
311 		ret = wfx_igpr_reg_write(wdev, gpr_init[i].index, gpr_init[i].value);
312 		if (ret < 0)
313 			return ret;
314 		dev_dbg(wdev->dev, "  index %02x: %08x\n", gpr_init[i].index, gpr_init[i].value);
315 	}
316 	return 0;
317 }
318 
319 int wfx_init_device(struct wfx_dev *wdev)
320 {
321 	int ret;
322 	int hw_revision, hw_type;
323 	int wakeup_timeout = 50; /* ms */
324 	ktime_t now, start;
325 	u32 reg;
326 
327 	reg = CFG_DIRECT_ACCESS_MODE | CFG_CPU_RESET | CFG_BYTE_ORDER_ABCD;
328 	if (wdev->pdata.use_rising_clk)
329 		reg |= CFG_CLK_RISE_EDGE;
330 	ret = wfx_config_reg_write(wdev, reg);
331 	if (ret < 0) {
332 		dev_err(wdev->dev, "bus returned an error during first write access. Host configuration error?\n");
333 		return -EIO;
334 	}
335 
336 	ret = wfx_config_reg_read(wdev, &reg);
337 	if (ret < 0) {
338 		dev_err(wdev->dev, "bus returned an error during first read access. Bus configuration error?\n");
339 		return -EIO;
340 	}
341 	if (reg == 0 || reg == ~0) {
342 		dev_err(wdev->dev, "chip mute. Bus configuration error or chip wasn't reset?\n");
343 		return -EIO;
344 	}
345 	dev_dbg(wdev->dev, "initial config register value: %08x\n", reg);
346 
347 	hw_revision = FIELD_GET(CFG_DEVICE_ID_MAJOR, reg);
348 	if (hw_revision == 0) {
349 		dev_err(wdev->dev, "bad hardware revision number: %d\n", hw_revision);
350 		return -ENODEV;
351 	}
352 	hw_type = FIELD_GET(CFG_DEVICE_ID_TYPE, reg);
353 	if (hw_type == 1) {
354 		dev_notice(wdev->dev, "development hardware detected\n");
355 		wakeup_timeout = 2000;
356 	}
357 
358 	ret = init_gpr(wdev);
359 	if (ret < 0)
360 		return ret;
361 
362 	ret = wfx_control_reg_write(wdev, CTRL_WLAN_WAKEUP);
363 	if (ret < 0)
364 		return -EIO;
365 	start = ktime_get();
366 	for (;;) {
367 		ret = wfx_control_reg_read(wdev, &reg);
368 		now = ktime_get();
369 		if (reg & CTRL_WLAN_READY)
370 			break;
371 		if (ktime_after(now, ktime_add_ms(start, wakeup_timeout))) {
372 			dev_err(wdev->dev, "chip didn't wake up. Chip wasn't reset?\n");
373 			return -ETIMEDOUT;
374 		}
375 	}
376 	dev_dbg(wdev->dev, "chip wake up after %lldus\n", ktime_us_delta(now, start));
377 
378 	ret = wfx_config_reg_write_bits(wdev, CFG_CPU_RESET, 0);
379 	if (ret < 0)
380 		return ret;
381 	ret = load_firmware_secure(wdev);
382 	if (ret < 0)
383 		return ret;
384 	return wfx_config_reg_write_bits(wdev,
385 					 CFG_DIRECT_ACCESS_MODE |
386 					 CFG_IRQ_ENABLE_DATA |
387 					 CFG_IRQ_ENABLE_WRDY,
388 					 CFG_IRQ_ENABLE_DATA);
389 }
390