1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the Intel SCU IPC mechanism
4  *
5  * (C) Copyright 2008-2010,2015 Intel Corporation
6  * Author: Sreedhara DS (sreedhara.ds@intel.com)
7  *
8  * SCU running in ARC processor communicates with other entity running in IA
9  * core through IPC mechanism which in turn messaging between IA core ad SCU.
10  * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and
11  * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with
12  * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC)
13  * along with other APIs.
14  */
15 
16 #include <linux/delay.h>
17 #include <linux/device.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/pci.h>
22 #include <linux/pm.h>
23 #include <linux/sfi.h>
24 
25 #include <asm/intel-mid.h>
26 #include <asm/intel_scu_ipc.h>
27 
28 /* IPC defines the following message types */
29 #define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
30 #define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
31 #define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
32 #define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
33 #define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
34 
35 /* Command id associated with message IPCMSG_PCNTRL */
36 #define IPC_CMD_PCNTRL_W      0 /* Register write */
37 #define IPC_CMD_PCNTRL_R      1 /* Register read */
38 #define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
39 
40 /*
41  * IPC register summary
42  *
43  * IPC register blocks are memory mapped at fixed address of PCI BAR 0.
44  * To read or write information to the SCU, driver writes to IPC-1 memory
45  * mapped registers. The following is the IPC mechanism
46  *
47  * 1. IA core cDMI interface claims this transaction and converts it to a
48  *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
49  *
50  * 2. South Complex cDMI block receives this message and writes it to
51  *    the IPC-1 register block, causing an interrupt to the SCU
52  *
53  * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
54  *    message handler is called within firmware.
55  */
56 
57 #define IPC_WWBUF_SIZE    20		/* IPC Write buffer Size */
58 #define IPC_RWBUF_SIZE    20		/* IPC Read buffer Size */
59 #define IPC_IOC	          0x100		/* IPC command register IOC bit */
60 
61 #define PCI_DEVICE_ID_LINCROFT		0x082a
62 #define PCI_DEVICE_ID_PENWELL		0x080e
63 #define PCI_DEVICE_ID_CLOVERVIEW	0x08ea
64 #define PCI_DEVICE_ID_TANGIER		0x11a0
65 
66 /* intel scu ipc driver data */
67 struct intel_scu_ipc_pdata_t {
68 	u32 i2c_base;
69 	u32 i2c_len;
70 	u8 irq_mode;
71 };
72 
73 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_lincroft_pdata = {
74 	.i2c_base = 0xff12b000,
75 	.i2c_len = 0x10,
76 	.irq_mode = 0,
77 };
78 
79 /* Penwell and Cloverview */
80 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_penwell_pdata = {
81 	.i2c_base = 0xff12b000,
82 	.i2c_len = 0x10,
83 	.irq_mode = 1,
84 };
85 
86 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_tangier_pdata = {
87 	.i2c_base  = 0xff00d000,
88 	.i2c_len = 0x10,
89 	.irq_mode = 0,
90 };
91 
92 struct intel_scu_ipc_dev {
93 	struct device *dev;
94 	void __iomem *ipc_base;
95 	void __iomem *i2c_base;
96 	struct completion cmd_complete;
97 	u8 irq_mode;
98 };
99 
100 static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
101 
102 /*
103  * IPC Read Buffer (Read Only):
104  * 16 byte buffer for receiving data from SCU, if IPC command
105  * processing results in response data
106  */
107 #define IPC_READ_BUFFER		0x90
108 
109 #define IPC_I2C_CNTRL_ADDR	0
110 #define I2C_DATA_ADDR		0x04
111 
112 static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
113 
114 /*
115  * Send ipc command
116  * Command Register (Write Only):
117  * A write to this register results in an interrupt to the SCU core processor
118  * Format:
119  * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
120  */
121 static inline void ipc_command(struct intel_scu_ipc_dev *scu, u32 cmd)
122 {
123 	if (scu->irq_mode) {
124 		reinit_completion(&scu->cmd_complete);
125 		writel(cmd | IPC_IOC, scu->ipc_base);
126 	}
127 	writel(cmd, scu->ipc_base);
128 }
129 
130 /*
131  * Write ipc data
132  * IPC Write Buffer (Write Only):
133  * 16-byte buffer for sending data associated with IPC command to
134  * SCU. Size of the data is specified in the IPC_COMMAND_REG register
135  */
136 static inline void ipc_data_writel(struct intel_scu_ipc_dev *scu, u32 data, u32 offset)
137 {
138 	writel(data, scu->ipc_base + 0x80 + offset);
139 }
140 
141 /*
142  * Status Register (Read Only):
143  * Driver will read this register to get the ready/busy status of the IPC
144  * block and error status of the IPC command that was just processed by SCU
145  * Format:
146  * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
147  */
148 static inline u8 ipc_read_status(struct intel_scu_ipc_dev *scu)
149 {
150 	return __raw_readl(scu->ipc_base + 0x04);
151 }
152 
153 /* Read ipc byte data */
154 static inline u8 ipc_data_readb(struct intel_scu_ipc_dev *scu, u32 offset)
155 {
156 	return readb(scu->ipc_base + IPC_READ_BUFFER + offset);
157 }
158 
159 /* Read ipc u32 data */
160 static inline u32 ipc_data_readl(struct intel_scu_ipc_dev *scu, u32 offset)
161 {
162 	return readl(scu->ipc_base + IPC_READ_BUFFER + offset);
163 }
164 
165 /* Wait till scu status is busy */
166 static inline int busy_loop(struct intel_scu_ipc_dev *scu)
167 {
168 	u32 status = ipc_read_status(scu);
169 	u32 loop_count = 100000;
170 
171 	/* break if scu doesn't reset busy bit after huge retry */
172 	while ((status & BIT(0)) && --loop_count) {
173 		udelay(1); /* scu processing time is in few u secods */
174 		status = ipc_read_status(scu);
175 	}
176 
177 	if (status & BIT(0)) {
178 		dev_err(scu->dev, "IPC timed out");
179 		return -ETIMEDOUT;
180 	}
181 
182 	if (status & BIT(1))
183 		return -EIO;
184 
185 	return 0;
186 }
187 
188 /* Wait till ipc ioc interrupt is received or timeout in 3 HZ */
189 static inline int ipc_wait_for_interrupt(struct intel_scu_ipc_dev *scu)
190 {
191 	int status;
192 
193 	if (!wait_for_completion_timeout(&scu->cmd_complete, 3 * HZ)) {
194 		dev_err(scu->dev, "IPC timed out\n");
195 		return -ETIMEDOUT;
196 	}
197 
198 	status = ipc_read_status(scu);
199 	if (status & BIT(1))
200 		return -EIO;
201 
202 	return 0;
203 }
204 
205 static int intel_scu_ipc_check_status(struct intel_scu_ipc_dev *scu)
206 {
207 	return scu->irq_mode ? ipc_wait_for_interrupt(scu) : busy_loop(scu);
208 }
209 
210 /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
211 static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
212 {
213 	struct intel_scu_ipc_dev *scu = &ipcdev;
214 	int nc;
215 	u32 offset = 0;
216 	int err;
217 	u8 cbuf[IPC_WWBUF_SIZE];
218 	u32 *wbuf = (u32 *)&cbuf;
219 
220 	memset(cbuf, 0, sizeof(cbuf));
221 
222 	mutex_lock(&ipclock);
223 
224 	if (scu->dev == NULL) {
225 		mutex_unlock(&ipclock);
226 		return -ENODEV;
227 	}
228 
229 	for (nc = 0; nc < count; nc++, offset += 2) {
230 		cbuf[offset] = addr[nc];
231 		cbuf[offset + 1] = addr[nc] >> 8;
232 	}
233 
234 	if (id == IPC_CMD_PCNTRL_R) {
235 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
236 			ipc_data_writel(scu, wbuf[nc], offset);
237 		ipc_command(scu, (count * 2) << 16 | id << 12 | 0 << 8 | op);
238 	} else if (id == IPC_CMD_PCNTRL_W) {
239 		for (nc = 0; nc < count; nc++, offset += 1)
240 			cbuf[offset] = data[nc];
241 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
242 			ipc_data_writel(scu, wbuf[nc], offset);
243 		ipc_command(scu, (count * 3) << 16 | id << 12 | 0 << 8 | op);
244 	} else if (id == IPC_CMD_PCNTRL_M) {
245 		cbuf[offset] = data[0];
246 		cbuf[offset + 1] = data[1];
247 		ipc_data_writel(scu, wbuf[0], 0); /* Write wbuff */
248 		ipc_command(scu, 4 << 16 | id << 12 | 0 << 8 | op);
249 	}
250 
251 	err = intel_scu_ipc_check_status(scu);
252 	if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
253 		/* Workaround: values are read as 0 without memcpy_fromio */
254 		memcpy_fromio(cbuf, scu->ipc_base + 0x90, 16);
255 		for (nc = 0; nc < count; nc++)
256 			data[nc] = ipc_data_readb(scu, nc);
257 	}
258 	mutex_unlock(&ipclock);
259 	return err;
260 }
261 
262 /**
263  *	intel_scu_ipc_ioread8		-	read a word via the SCU
264  *	@addr: register on SCU
265  *	@data: return pointer for read byte
266  *
267  *	Read a single register. Returns 0 on success or an error code. All
268  *	locking between SCU accesses is handled for the caller.
269  *
270  *	This function may sleep.
271  */
272 int intel_scu_ipc_ioread8(u16 addr, u8 *data)
273 {
274 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
275 }
276 EXPORT_SYMBOL(intel_scu_ipc_ioread8);
277 
278 /**
279  *	intel_scu_ipc_ioread16		-	read a word via the SCU
280  *	@addr: register on SCU
281  *	@data: return pointer for read word
282  *
283  *	Read a register pair. Returns 0 on success or an error code. All
284  *	locking between SCU accesses is handled for the caller.
285  *
286  *	This function may sleep.
287  */
288 int intel_scu_ipc_ioread16(u16 addr, u16 *data)
289 {
290 	u16 x[2] = {addr, addr + 1};
291 	return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
292 }
293 EXPORT_SYMBOL(intel_scu_ipc_ioread16);
294 
295 /**
296  *	intel_scu_ipc_ioread32		-	read a dword via the SCU
297  *	@addr: register on SCU
298  *	@data: return pointer for read dword
299  *
300  *	Read four registers. Returns 0 on success or an error code. All
301  *	locking between SCU accesses is handled for the caller.
302  *
303  *	This function may sleep.
304  */
305 int intel_scu_ipc_ioread32(u16 addr, u32 *data)
306 {
307 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
308 	return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
309 }
310 EXPORT_SYMBOL(intel_scu_ipc_ioread32);
311 
312 /**
313  *	intel_scu_ipc_iowrite8		-	write a byte via the SCU
314  *	@addr: register on SCU
315  *	@data: byte to write
316  *
317  *	Write a single register. Returns 0 on success or an error code. All
318  *	locking between SCU accesses is handled for the caller.
319  *
320  *	This function may sleep.
321  */
322 int intel_scu_ipc_iowrite8(u16 addr, u8 data)
323 {
324 	return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
325 }
326 EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
327 
328 /**
329  *	intel_scu_ipc_iowrite16		-	write a word via the SCU
330  *	@addr: register on SCU
331  *	@data: word to write
332  *
333  *	Write two registers. Returns 0 on success or an error code. All
334  *	locking between SCU accesses is handled for the caller.
335  *
336  *	This function may sleep.
337  */
338 int intel_scu_ipc_iowrite16(u16 addr, u16 data)
339 {
340 	u16 x[2] = {addr, addr + 1};
341 	return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
342 }
343 EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
344 
345 /**
346  *	intel_scu_ipc_iowrite32		-	write a dword via the SCU
347  *	@addr: register on SCU
348  *	@data: dword to write
349  *
350  *	Write four registers. Returns 0 on success or an error code. All
351  *	locking between SCU accesses is handled for the caller.
352  *
353  *	This function may sleep.
354  */
355 int intel_scu_ipc_iowrite32(u16 addr, u32 data)
356 {
357 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
358 	return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
359 }
360 EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
361 
362 /**
363  *	intel_scu_ipc_readvv		-	read a set of registers
364  *	@addr: register list
365  *	@data: bytes to return
366  *	@len: length of array
367  *
368  *	Read registers. Returns 0 on success or an error code. All
369  *	locking between SCU accesses is handled for the caller.
370  *
371  *	The largest array length permitted by the hardware is 5 items.
372  *
373  *	This function may sleep.
374  */
375 int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
376 {
377 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
378 }
379 EXPORT_SYMBOL(intel_scu_ipc_readv);
380 
381 /**
382  *	intel_scu_ipc_writev		-	write a set of registers
383  *	@addr: register list
384  *	@data: bytes to write
385  *	@len: length of array
386  *
387  *	Write registers. Returns 0 on success or an error code. All
388  *	locking between SCU accesses is handled for the caller.
389  *
390  *	The largest array length permitted by the hardware is 5 items.
391  *
392  *	This function may sleep.
393  *
394  */
395 int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
396 {
397 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
398 }
399 EXPORT_SYMBOL(intel_scu_ipc_writev);
400 
401 /**
402  *	intel_scu_ipc_update_register	-	r/m/w a register
403  *	@addr: register address
404  *	@bits: bits to update
405  *	@mask: mask of bits to update
406  *
407  *	Read-modify-write power control unit register. The first data argument
408  *	must be register value and second is mask value
409  *	mask is a bitmap that indicates which bits to update.
410  *	0 = masked. Don't modify this bit, 1 = modify this bit.
411  *	returns 0 on success or an error code.
412  *
413  *	This function may sleep. Locking between SCU accesses is handled
414  *	for the caller.
415  */
416 int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
417 {
418 	u8 data[2] = { bits, mask };
419 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
420 }
421 EXPORT_SYMBOL(intel_scu_ipc_update_register);
422 
423 /**
424  *	intel_scu_ipc_simple_command	-	send a simple command
425  *	@cmd: command
426  *	@sub: sub type
427  *
428  *	Issue a simple command to the SCU. Do not use this interface if
429  *	you must then access data as any data values may be overwritten
430  *	by another SCU access by the time this function returns.
431  *
432  *	This function may sleep. Locking for SCU accesses is handled for
433  *	the caller.
434  */
435 int intel_scu_ipc_simple_command(int cmd, int sub)
436 {
437 	struct intel_scu_ipc_dev *scu = &ipcdev;
438 	int err;
439 
440 	mutex_lock(&ipclock);
441 	if (scu->dev == NULL) {
442 		mutex_unlock(&ipclock);
443 		return -ENODEV;
444 	}
445 	ipc_command(scu, sub << 12 | cmd);
446 	err = intel_scu_ipc_check_status(scu);
447 	mutex_unlock(&ipclock);
448 	return err;
449 }
450 EXPORT_SYMBOL(intel_scu_ipc_simple_command);
451 
452 /**
453  *	intel_scu_ipc_command	-	command with data
454  *	@cmd: command
455  *	@sub: sub type
456  *	@in: input data
457  *	@inlen: input length in dwords
458  *	@out: output data
459  *	@outlein: output length in dwords
460  *
461  *	Issue a command to the SCU which involves data transfers. Do the
462  *	data copies under the lock but leave it for the caller to interpret
463  */
464 int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
465 			  u32 *out, int outlen)
466 {
467 	struct intel_scu_ipc_dev *scu = &ipcdev;
468 	int i, err;
469 
470 	mutex_lock(&ipclock);
471 	if (scu->dev == NULL) {
472 		mutex_unlock(&ipclock);
473 		return -ENODEV;
474 	}
475 
476 	for (i = 0; i < inlen; i++)
477 		ipc_data_writel(scu, *in++, 4 * i);
478 
479 	ipc_command(scu, (inlen << 16) | (sub << 12) | cmd);
480 	err = intel_scu_ipc_check_status(scu);
481 
482 	if (!err) {
483 		for (i = 0; i < outlen; i++)
484 			*out++ = ipc_data_readl(scu, 4 * i);
485 	}
486 
487 	mutex_unlock(&ipclock);
488 	return err;
489 }
490 EXPORT_SYMBOL(intel_scu_ipc_command);
491 
492 #define IPC_SPTR		0x08
493 #define IPC_DPTR		0x0C
494 
495 /**
496  * intel_scu_ipc_raw_command() - IPC command with data and pointers
497  * @cmd:	IPC command code.
498  * @sub:	IPC command sub type.
499  * @in:		input data of this IPC command.
500  * @inlen:	input data length in dwords.
501  * @out:	output data of this IPC command.
502  * @outlen:	output data length in dwords.
503  * @sptr:	data writing to SPTR register.
504  * @dptr:	data writing to DPTR register.
505  *
506  * Send an IPC command to SCU with input/output data and source/dest pointers.
507  *
508  * Return:	an IPC error code or 0 on success.
509  */
510 int intel_scu_ipc_raw_command(int cmd, int sub, u8 *in, int inlen,
511 			      u32 *out, int outlen, u32 dptr, u32 sptr)
512 {
513 	struct intel_scu_ipc_dev *scu = &ipcdev;
514 	int inbuflen = DIV_ROUND_UP(inlen, 4);
515 	u32 inbuf[4];
516 	int i, err;
517 
518 	/* Up to 16 bytes */
519 	if (inbuflen > 4)
520 		return -EINVAL;
521 
522 	mutex_lock(&ipclock);
523 	if (scu->dev == NULL) {
524 		mutex_unlock(&ipclock);
525 		return -ENODEV;
526 	}
527 
528 	writel(dptr, scu->ipc_base + IPC_DPTR);
529 	writel(sptr, scu->ipc_base + IPC_SPTR);
530 
531 	/*
532 	 * SRAM controller doesn't support 8-bit writes, it only
533 	 * supports 32-bit writes, so we have to copy input data into
534 	 * the temporary buffer, and SCU FW will use the inlen to
535 	 * determine the actual input data length in the temporary
536 	 * buffer.
537 	 */
538 	memcpy(inbuf, in, inlen);
539 
540 	for (i = 0; i < inbuflen; i++)
541 		ipc_data_writel(scu, inbuf[i], 4 * i);
542 
543 	ipc_command(scu, (inlen << 16) | (sub << 12) | cmd);
544 	err = intel_scu_ipc_check_status(scu);
545 	if (!err) {
546 		for (i = 0; i < outlen; i++)
547 			*out++ = ipc_data_readl(scu, 4 * i);
548 	}
549 
550 	mutex_unlock(&ipclock);
551 	return err;
552 }
553 EXPORT_SYMBOL_GPL(intel_scu_ipc_raw_command);
554 
555 /* I2C commands */
556 #define IPC_I2C_WRITE 1 /* I2C Write command */
557 #define IPC_I2C_READ  2 /* I2C Read command */
558 
559 /**
560  *	intel_scu_ipc_i2c_cntrl		-	I2C read/write operations
561  *	@addr: I2C address + command bits
562  *	@data: data to read/write
563  *
564  *	Perform an an I2C read/write operation via the SCU. All locking is
565  *	handled for the caller. This function may sleep.
566  *
567  *	Returns an error code or 0 on success.
568  *
569  *	This has to be in the IPC driver for the locking.
570  */
571 int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
572 {
573 	struct intel_scu_ipc_dev *scu = &ipcdev;
574 	u32 cmd = 0;
575 
576 	mutex_lock(&ipclock);
577 	if (scu->dev == NULL) {
578 		mutex_unlock(&ipclock);
579 		return -ENODEV;
580 	}
581 	cmd = (addr >> 24) & 0xFF;
582 	if (cmd == IPC_I2C_READ) {
583 		writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
584 		/* Write not getting updated without delay */
585 		usleep_range(1000, 2000);
586 		*data = readl(scu->i2c_base + I2C_DATA_ADDR);
587 	} else if (cmd == IPC_I2C_WRITE) {
588 		writel(*data, scu->i2c_base + I2C_DATA_ADDR);
589 		usleep_range(1000, 2000);
590 		writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
591 	} else {
592 		dev_err(scu->dev,
593 			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
594 
595 		mutex_unlock(&ipclock);
596 		return -EIO;
597 	}
598 	mutex_unlock(&ipclock);
599 	return 0;
600 }
601 EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
602 
603 /*
604  * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
605  * When ioc bit is set to 1, caller api must wait for interrupt handler called
606  * which in turn unlocks the caller api. Currently this is not used
607  *
608  * This is edge triggered so we need take no action to clear anything
609  */
610 static irqreturn_t ioc(int irq, void *dev_id)
611 {
612 	struct intel_scu_ipc_dev *scu = dev_id;
613 
614 	if (scu->irq_mode)
615 		complete(&scu->cmd_complete);
616 
617 	return IRQ_HANDLED;
618 }
619 
620 /**
621  *	ipc_probe	-	probe an Intel SCU IPC
622  *	@pdev: the PCI device matching
623  *	@id: entry in the match table
624  *
625  *	Enable and install an intel SCU IPC. This appears in the PCI space
626  *	but uses some hard coded addresses as well.
627  */
628 static int ipc_probe(struct pci_dev *pdev, const struct pci_device_id *id)
629 {
630 	int err;
631 	struct intel_scu_ipc_dev *scu = &ipcdev;
632 	struct intel_scu_ipc_pdata_t *pdata;
633 
634 	if (scu->dev)		/* We support only one SCU */
635 		return -EBUSY;
636 
637 	pdata = (struct intel_scu_ipc_pdata_t *)id->driver_data;
638 	if (!pdata)
639 		return -ENODEV;
640 
641 	scu->irq_mode = pdata->irq_mode;
642 
643 	err = pcim_enable_device(pdev);
644 	if (err)
645 		return err;
646 
647 	err = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
648 	if (err)
649 		return err;
650 
651 	init_completion(&scu->cmd_complete);
652 
653 	scu->ipc_base = pcim_iomap_table(pdev)[0];
654 
655 	scu->i2c_base = ioremap_nocache(pdata->i2c_base, pdata->i2c_len);
656 	if (!scu->i2c_base)
657 		return -ENOMEM;
658 
659 	err = devm_request_irq(&pdev->dev, pdev->irq, ioc, 0, "intel_scu_ipc",
660 			       scu);
661 	if (err)
662 		return err;
663 
664 	/* Assign device at last */
665 	scu->dev = &pdev->dev;
666 
667 	intel_scu_devices_create();
668 
669 	pci_set_drvdata(pdev, scu);
670 	return 0;
671 }
672 
673 #define SCU_DEVICE(id, pdata)	{PCI_VDEVICE(INTEL, id), (kernel_ulong_t)&pdata}
674 
675 static const struct pci_device_id pci_ids[] = {
676 	SCU_DEVICE(PCI_DEVICE_ID_LINCROFT,	intel_scu_ipc_lincroft_pdata),
677 	SCU_DEVICE(PCI_DEVICE_ID_PENWELL,	intel_scu_ipc_penwell_pdata),
678 	SCU_DEVICE(PCI_DEVICE_ID_CLOVERVIEW,	intel_scu_ipc_penwell_pdata),
679 	SCU_DEVICE(PCI_DEVICE_ID_TANGIER,	intel_scu_ipc_tangier_pdata),
680 	{}
681 };
682 
683 static struct pci_driver ipc_driver = {
684 	.driver = {
685 		.suppress_bind_attrs = true,
686 	},
687 	.name = "intel_scu_ipc",
688 	.id_table = pci_ids,
689 	.probe = ipc_probe,
690 };
691 builtin_pci_driver(ipc_driver);
692