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