1 /*
2  * This file is part of the flashrom project.
3  *
4  * Copyright (C) 2007, 2008, 2009 Carl-Daniel Hailfinger
5  * Copyright (C) 2008 Ronald Hoogenboom <ronald@zonnet.nl>
6  * Copyright (C) 2008 coresystems GmbH
7  * Copyright (C) 2010 Google Inc.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; version 2 of the License.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  */
18 
19 /*
20  * Contains the ITE IT85* SPI specific routines
21  */
22 
23 #if defined(__i386__) || defined(__x86_64__)
24 
25 #include <string.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include "flash.h"
29 #include "spi.h"
30 #include "programmer.h"
31 #include "hwaccess.h"
32 
33 #define MAX_TIMEOUT 100000
34 #define MAX_TRY 5
35 
36 /* Constants for I/O ports */
37 #define ITE_SUPERIO_PORT1	0x2e
38 #define ITE_SUPERIO_PORT2	0x4e
39 
40 /* Legacy I/O */
41 #define LEGACY_KBC_PORT_DATA	0x60
42 #define LEGACY_KBC_PORT_CMD	0x64
43 
44 /* Constants for Logical Device registers */
45 #define LDNSEL			0x07
46 
47 /* These are standard Super I/O 16-bit base address registers */
48 #define SHM_IO_BAR0		0x60  /* big-endian, this is high bits */
49 #define SHM_IO_BAR1		0x61
50 
51 /* The 8042 keyboard controller uses an input buffer and an output buffer to
52  * communicate with the host CPU. Both buffers are 1-byte depth. That means
53  * IBF is set to 1 when the host CPU sends a command to the input buffer
54  * of the EC. IBF is cleared to 0 once the command is read by the EC.
55  */
56 #define KB_IBF			(1 << 1)  /* Input Buffer Full */
57 #define KB_OBF			(1 << 0)  /* Output Buffer Full */
58 
59 /* IT8502 supports two access modes:
60  *   LPC_MEMORY: through the memory window in 0xFFFFFxxx (follow mode)
61  *   LPC_IO: through I/O port (so called indirect memory)
62  */
63 #undef LPC_MEMORY
64 #define LPC_IO
65 
66 #ifdef LPC_IO
67 /* macro to fill in indirect-access registers. */
68 #define INDIRECT_A0(base, value) OUTB(value, (base) + 0)  /* little-endian */
69 #define INDIRECT_A1(base, value) OUTB(value, (base) + 1)
70 #define INDIRECT_A2(base, value) OUTB(value, (base) + 2)
71 #define INDIRECT_A3(base, value) OUTB(value, (base) + 3)
72 #define INDIRECT_READ(base) INB((base) + 4)
73 #define INDIRECT_WRITE(base, value) OUTB(value, (base) + 4)
74 #endif  /* LPC_IO */
75 
76 #ifdef LPC_IO
77 static unsigned int shm_io_base;
78 #endif
79 static unsigned char *ce_high, *ce_low;
80 static int it85xx_scratch_rom_reenter = 0;
81 
82 /* This function will poll the keyboard status register until either
83  * an expected value shows up, or the timeout is reached.
84  * timeout is in usec.
85  *
86  * Returns: 0 -- the expected value showed up.
87  *          1 -- timeout.
88  */
89 static int wait_for(const unsigned int mask, const unsigned int expected_value,
90 		    const int timeout, const char * error_message,
91 		    const char * function_name, const int lineno)
92 {
93 	int time_passed;
94 
95 	for (time_passed = 0;; ++time_passed) {
96 		if ((INB(LEGACY_KBC_PORT_CMD) & mask) == expected_value)
97 			return 0;
98 		if (time_passed >= timeout)
99 			break;
100 		programmer_delay(1);
101 	}
102 	if (error_message)
103 		msg_perr("%s():%d %s", function_name, lineno, error_message);
104 	return 1;
105 }
106 
107 /* IT8502 employs a scratch RAM when flash is being updated. Call the following
108  * two functions before/after flash erase/program. */
109 static void it85xx_enter_scratch_rom(void)
110 {
111 	int ret, tries;
112 
113 	msg_pdbg("%s():%d was called ...\n", __func__, __LINE__);
114 	if (it85xx_scratch_rom_reenter > 0)
115 		return;
116 
117 #if 0
118 	/* FIXME: this a workaround for the bug that SMBus signal would
119 	 *        interfere the EC firmware update. Should be removed if
120 	 *        we find out the root cause. */
121 	ret = system("stop powerd >&2");
122 	if (ret)
123 		msg_perr("Cannot stop powerd.\n");
124 #endif
125 
126 	for (tries = 0; tries < MAX_TRY; ++tries) {
127 		/* Wait until IBF (input buffer) is not full. */
128 		if (wait_for(KB_IBF, 0, MAX_TIMEOUT,
129 		             "* timeout at waiting for IBF==0.\n",
130 		             __func__, __LINE__))
131 			continue;
132 
133 		/* Copy EC firmware to SRAM. */
134 		OUTB(0xb4, LEGACY_KBC_PORT_CMD);
135 
136 		/* Confirm EC has taken away the command. */
137 		if (wait_for(KB_IBF, 0, MAX_TIMEOUT,
138 		             "* timeout at taking command.\n",
139 		             __func__, __LINE__))
140 			continue;
141 
142 		/* Waiting for OBF (output buffer) has data.
143 		 * Note sometimes the replied command might be stolen by kernel
144 		 * ISR so that it is okay as long as the command is 0xFA. */
145 		if (wait_for(KB_OBF, KB_OBF, MAX_TIMEOUT, NULL, NULL, 0))
146 			msg_pdbg("%s():%d * timeout at waiting for OBF.\n",
147 			         __func__, __LINE__);
148 		if ((ret = INB(LEGACY_KBC_PORT_DATA)) == 0xFA) {
149 			break;
150 		} else {
151 			msg_perr("%s():%d * not run on SRAM ret=%d\n",
152 			         __func__, __LINE__, ret);
153 			continue;
154 		}
155 	}
156 
157 	if (tries < MAX_TRY) {
158 		/* EC already runs on SRAM */
159 		it85xx_scratch_rom_reenter++;
160 		msg_pdbg("%s():%d * SUCCESS.\n", __func__, __LINE__);
161 	} else {
162 		msg_perr("%s():%d * Max try reached.\n", __func__, __LINE__);
163 	}
164 }
165 
166 static void it85xx_exit_scratch_rom(void)
167 {
168 #if 0
169 	int ret;
170 #endif
171 	int tries;
172 
173 	msg_pdbg("%s():%d was called ...\n", __func__, __LINE__);
174 	if (it85xx_scratch_rom_reenter <= 0)
175 		return;
176 
177 	for (tries = 0; tries < MAX_TRY; ++tries) {
178 		/* Wait until IBF (input buffer) is not full. */
179 		if (wait_for(KB_IBF, 0, MAX_TIMEOUT,
180 		             "* timeout at waiting for IBF==0.\n",
181 		             __func__, __LINE__))
182 			continue;
183 
184 		/* Exit SRAM. Run on flash. */
185 		OUTB(0xFE, LEGACY_KBC_PORT_CMD);
186 
187 		/* Confirm EC has taken away the command. */
188 		if (wait_for(KB_IBF, 0, MAX_TIMEOUT,
189 		             "* timeout at taking command.\n",
190 		             __func__, __LINE__)) {
191 			/* We cannot ensure if EC has exited update mode.
192 			 * If EC is in normal mode already, a further 0xFE
193 			 * command will reboot system. So, exit loop here. */
194 			tries = MAX_TRY;
195 			break;
196 		}
197 
198 		break;
199 	}
200 
201 	if (tries < MAX_TRY) {
202 		it85xx_scratch_rom_reenter = 0;
203 		msg_pdbg("%s():%d * SUCCESS.\n", __func__, __LINE__);
204 	} else {
205 		msg_perr("%s():%d * Max try reached.\n", __func__, __LINE__);
206 	}
207 
208 #if 0
209 	/* FIXME: this a workaround for the bug that SMBus signal would
210 	 *        interfere the EC firmware update. Should be removed if
211 	 *        we find out the root cause. */
212 	ret = system("start powerd >&2");
213 	if (ret)
214 		msg_perr("Cannot start powerd again.\n");
215 #endif
216 }
217 
218 static int it85xx_shutdown(void *data)
219 {
220 	msg_pdbg("%s():%d\n", __func__, __LINE__);
221 	it85xx_exit_scratch_rom();
222 
223 	return 0;	/* FIXME: Should probably return something meaningful */
224 }
225 
226 static int it85xx_spi_common_init(struct superio s)
227 {
228 	chipaddr base;
229 
230 	msg_pdbg("%s():%d superio.vendor=0x%02x\n", __func__, __LINE__,
231 	         s.vendor);
232 
233 	if (register_shutdown(it85xx_shutdown, NULL))
234 		return 1;
235 
236 #ifdef LPC_IO
237 	/* Get LPCPNP of SHM. That's big-endian. */
238 	sio_write(s.port, LDNSEL, 0x0F); /* Set LDN to SHM (0x0F) */
239 	shm_io_base = (sio_read(s.port, SHM_IO_BAR0) << 8) +
240 	              sio_read(s.port, SHM_IO_BAR1);
241 	msg_pdbg("%s():%d shm_io_base=0x%04x\n", __func__, __LINE__,
242 	         shm_io_base);
243 
244 	/* These pointers are not used directly. They will be send to EC's
245 	 * register for indirect access. */
246 	base = 0xFFFFF000;
247 	ce_high = ((unsigned char *)base) + 0xE00;  /* 0xFFFFFE00 */
248 	ce_low = ((unsigned char *)base) + 0xD00;  /* 0xFFFFFD00 */
249 
250 	/* pre-set indirect-access registers since in most of cases they are
251 	 * 0xFFFFxx00. */
252 	INDIRECT_A0(shm_io_base, base & 0xFF);
253 	INDIRECT_A2(shm_io_base, (base >> 16) & 0xFF);
254 	INDIRECT_A3(shm_io_base, (base >> 24));
255 #endif
256 #ifdef LPC_MEMORY
257 	/* FIXME: We should block accessing that region for anything else.
258 	 * Major TODO here, and it will be a lot of work.
259 	 */
260 	base = (chipaddr)physmap("it85 communication", 0xFFFFF000, 0x1000);
261 	if (base == (chipaddr)ERROR_PTR)
262 		return 1;
263 
264 	msg_pdbg("%s():%d base=0x%08x\n", __func__, __LINE__,
265 	         (unsigned int)base);
266 	ce_high = (unsigned char *)(base + 0xE00);  /* 0xFFFFFE00 */
267 	ce_low = (unsigned char *)(base + 0xD00);  /* 0xFFFFFD00 */
268 #endif
269 
270 	return 0;
271 }
272 
273 static int it85xx_spi_send_command(struct flashctx *flash,
274 				   unsigned int writecnt, unsigned int readcnt,
275 				   const unsigned char *writearr,
276 				   unsigned char *readarr);
277 
278 static const struct spi_master spi_master_it85xx = {
279 	.max_data_read	= 64,
280 	.max_data_write	= 64,
281 	.command	= it85xx_spi_send_command,
282 	.multicommand	= default_spi_send_multicommand,
283 	.read		= default_spi_read,
284 	.write_256	= default_spi_write_256,
285 	.write_aai	= default_spi_write_aai,
286 };
287 
288 int it85xx_spi_init(struct superio s)
289 {
290 	int ret;
291 
292 	if (!(internal_buses_supported & BUS_FWH)) {
293 		msg_pdbg("%s():%d buses not support FWH\n", __func__, __LINE__);
294 		return 1;
295 	}
296 	ret = it85xx_spi_common_init(s);
297 	msg_pdbg("FWH: %s():%d ret=%d\n", __func__, __LINE__, ret);
298 	if (!ret) {
299 		msg_pdbg("%s: internal_buses_supported=0x%x\n", __func__,
300 		          internal_buses_supported);
301 		/* Check for FWH because IT85 listens to FWH cycles.
302 		 * FIXME: The big question is whether FWH cycles are necessary
303 		 * for communication even if LPC_IO is defined.
304 		 */
305 		if (internal_buses_supported & BUS_FWH)
306 			msg_pdbg("Registering IT85 SPI.\n");
307 		/* FIXME: Really leave FWH enabled? We can't use this region
308 		 * anymore since accessing it would mess up IT85 communication.
309 		 * If we decide to disable FWH for this region, we should print
310 		 * a debug message about it.
311 		 */
312 		/* Set this as SPI controller. */
313 		register_spi_master(&spi_master_it85xx);
314 	}
315 	return ret;
316 }
317 
318 /* According to ITE 8502 document, the procedure to follow mode is following:
319  *   1. write 0x00 to LPC/FWH address 0xffff_fexxh (drive CE# high)
320  *   2. write data to LPC/FWH address 0xffff_fdxxh (drive CE# low and MOSI
321  *      with data)
322  *   3. read date from LPC/FWH address 0xffff_fdxxh (drive CE# low and get
323  *      data from MISO)
324  */
325 static int it85xx_spi_send_command(struct flashctx *flash,
326 				   unsigned int writecnt, unsigned int readcnt,
327 				   const unsigned char *writearr,
328 				   unsigned char *readarr)
329 {
330 	unsigned int i;
331 
332 	it85xx_enter_scratch_rom();
333 	/* Exit scratch ROM ONLY when programmer shuts down. Otherwise, the
334 	 * temporary flash state may halt the EC.
335 	 */
336 
337 #ifdef LPC_IO
338 	INDIRECT_A1(shm_io_base, (((unsigned long int)ce_high) >> 8) & 0xff);
339 	INDIRECT_WRITE(shm_io_base, 0xFF);  /* Write anything to this address.*/
340 	INDIRECT_A1(shm_io_base, (((unsigned long int)ce_low) >> 8) & 0xff);
341 #endif
342 #ifdef LPC_MEMORY
343 	mmio_writeb(0, ce_high);
344 #endif
345 	for (i = 0; i < writecnt; ++i) {
346 #ifdef LPC_IO
347 		INDIRECT_WRITE(shm_io_base, writearr[i]);
348 #endif
349 #ifdef LPC_MEMORY
350 		mmio_writeb(writearr[i], ce_low);
351 #endif
352 	}
353 	for (i = 0; i < readcnt; ++i) {
354 #ifdef LPC_IO
355 		readarr[i] = INDIRECT_READ(shm_io_base);
356 #endif
357 #ifdef LPC_MEMORY
358 		readarr[i] = mmio_readb(ce_low);
359 #endif
360 	}
361 #ifdef LPC_IO
362 	INDIRECT_A1(shm_io_base, (((unsigned long int)ce_high) >> 8) & 0xff);
363 	INDIRECT_WRITE(shm_io_base, 0xFF);  /* Write anything to this address.*/
364 #endif
365 #ifdef LPC_MEMORY
366 	mmio_writeb(0, ce_high);
367 #endif
368 
369 	return 0;
370 }
371 
372 #endif
373