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v3.1
  1/*
  2 * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism
  3 *
  4 * (C) Copyright 2008-2010 Intel Corporation
  5 * Author: Sreedhara DS (sreedhara.ds@intel.com)
  6 *
  7 * This program is free software; you can redistribute it and/or
  8 * modify it under the terms of the GNU General Public License
  9 * as published by the Free Software Foundation; version 2
 10 * of the License.
 11 *
 12 * SCU running in ARC processor communicates with other entity running in IA
 13 * core through IPC mechanism which in turn messaging between IA core ad SCU.
 14 * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and
 15 * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with
 16 * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC)
 17 * along with other APIs.
 18 */
 19#include <linux/delay.h>
 20#include <linux/errno.h>
 21#include <linux/init.h>
 22#include <linux/sysdev.h>
 23#include <linux/pm.h>
 24#include <linux/pci.h>
 25#include <linux/interrupt.h>
 26#include <linux/sfi.h>
 27#include <asm/mrst.h>
 
 28#include <asm/intel_scu_ipc.h>
 29
 30/* IPC defines the following message types */
 31#define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
 32#define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
 33#define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
 34#define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
 35#define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
 36
 37/* Command id associated with message IPCMSG_PCNTRL */
 38#define IPC_CMD_PCNTRL_W      0 /* Register write */
 39#define IPC_CMD_PCNTRL_R      1 /* Register read */
 40#define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
 41
 42/*
 43 * IPC register summary
 44 *
 45 * IPC register blocks are memory mapped at fixed address of 0xFF11C000
 46 * To read or write information to the SCU, driver writes to IPC-1 memory
 47 * mapped registers (base address 0xFF11C000). The following is the IPC
 48 * mechanism
 49 *
 50 * 1. IA core cDMI interface claims this transaction and converts it to a
 51 *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
 52 *
 53 * 2. South Complex cDMI block receives this message and writes it to
 54 *    the IPC-1 register block, causing an interrupt to the SCU
 55 *
 56 * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
 57 *    message handler is called within firmware.
 58 */
 59
 60#define IPC_BASE_ADDR     0xFF11C000	/* IPC1 base register address */
 61#define IPC_MAX_ADDR      0x100		/* Maximum IPC regisers */
 62#define IPC_WWBUF_SIZE    20		/* IPC Write buffer Size */
 63#define IPC_RWBUF_SIZE    20		/* IPC Read buffer Size */
 64#define IPC_I2C_BASE      0xFF12B000	/* I2C control register base address */
 65#define IPC_I2C_MAX_ADDR  0x10		/* Maximum I2C regisers */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 66
 67static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id);
 68static void ipc_remove(struct pci_dev *pdev);
 69
 70struct intel_scu_ipc_dev {
 71	struct pci_dev *pdev;
 72	void __iomem *ipc_base;
 73	void __iomem *i2c_base;
 
 
 74};
 75
 76static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
 77
 78static int platform;		/* Platform type */
 79
 80/*
 81 * IPC Read Buffer (Read Only):
 82 * 16 byte buffer for receiving data from SCU, if IPC command
 83 * processing results in response data
 84 */
 85#define IPC_READ_BUFFER		0x90
 86
 87#define IPC_I2C_CNTRL_ADDR	0
 88#define I2C_DATA_ADDR		0x04
 89
 90static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
 91
 92/*
 93 * Command Register (Write Only):
 94 * A write to this register results in an interrupt to the SCU core processor
 95 * Format:
 96 * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
 97 */
 98static inline void ipc_command(u32 cmd) /* Send ipc command */
 99{
 
 
 
 
100	writel(cmd, ipcdev.ipc_base);
101}
102
103/*
104 * IPC Write Buffer (Write Only):
105 * 16-byte buffer for sending data associated with IPC command to
106 * SCU. Size of the data is specified in the IPC_COMMAND_REG register
107 */
108static inline void ipc_data_writel(u32 data, u32 offset) /* Write ipc data */
109{
110	writel(data, ipcdev.ipc_base + 0x80 + offset);
111}
112
113/*
114 * Status Register (Read Only):
115 * Driver will read this register to get the ready/busy status of the IPC
116 * block and error status of the IPC command that was just processed by SCU
117 * Format:
118 * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
119 */
120
121static inline u8 ipc_read_status(void)
122{
123	return __raw_readl(ipcdev.ipc_base + 0x04);
124}
125
126static inline u8 ipc_data_readb(u32 offset) /* Read ipc byte data */
127{
128	return readb(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
129}
130
131static inline u32 ipc_data_readl(u32 offset) /* Read ipc u32 data */
132{
133	return readl(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
134}
135
136static inline int busy_loop(void) /* Wait till scu status is busy */
137{
138	u32 status = 0;
139	u32 loop_count = 0;
140
141	status = ipc_read_status();
142	while (status & 1) {
143		udelay(1); /* scu processing time is in few u secods */
144		status = ipc_read_status();
145		loop_count++;
146		/* break if scu doesn't reset busy bit after huge retry */
147		if (loop_count > 100000) {
148			dev_err(&ipcdev.pdev->dev, "IPC timed out");
149			return -ETIMEDOUT;
150		}
151	}
152	if ((status >> 1) & 1)
153		return -EIO;
154
155	return 0;
156}
157
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
158/* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
159static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
160{
161	int i, nc, bytes, d;
162	u32 offset = 0;
163	int err;
164	u8 cbuf[IPC_WWBUF_SIZE] = { };
165	u32 *wbuf = (u32 *)&cbuf;
166
167	mutex_lock(&ipclock);
168
169	memset(cbuf, 0, sizeof(cbuf));
170
171	if (ipcdev.pdev == NULL) {
172		mutex_unlock(&ipclock);
173		return -ENODEV;
174	}
175
176	if (platform != MRST_CPU_CHIP_PENWELL) {
177		bytes = 0;
178		d = 0;
179		for (i = 0; i < count; i++) {
180			cbuf[bytes++] = addr[i];
181			cbuf[bytes++] = addr[i] >> 8;
182			if (id != IPC_CMD_PCNTRL_R)
183				cbuf[bytes++] = data[d++];
184			if (id == IPC_CMD_PCNTRL_M)
185				cbuf[bytes++] = data[d++];
186		}
187		for (i = 0; i < bytes; i += 4)
188			ipc_data_writel(wbuf[i/4], i);
189		ipc_command(bytes << 16 |  id << 12 | 0 << 8 | op);
190	} else {
191		for (nc = 0; nc < count; nc++, offset += 2) {
192			cbuf[offset] = addr[nc];
193			cbuf[offset + 1] = addr[nc] >> 8;
194		}
195
196		if (id == IPC_CMD_PCNTRL_R) {
197			for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
198				ipc_data_writel(wbuf[nc], offset);
199			ipc_command((count*2) << 16 |  id << 12 | 0 << 8 | op);
200		} else if (id == IPC_CMD_PCNTRL_W) {
201			for (nc = 0; nc < count; nc++, offset += 1)
202				cbuf[offset] = data[nc];
203			for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
204				ipc_data_writel(wbuf[nc], offset);
205			ipc_command((count*3) << 16 |  id << 12 | 0 << 8 | op);
206		} else if (id == IPC_CMD_PCNTRL_M) {
207			cbuf[offset] = data[0];
208			cbuf[offset + 1] = data[1];
209			ipc_data_writel(wbuf[0], 0); /* Write wbuff */
210			ipc_command(4 << 16 |  id << 12 | 0 << 8 | op);
211		}
212	}
213
214	err = busy_loop();
215	if (id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
216		/* Workaround: values are read as 0 without memcpy_fromio */
217		memcpy_fromio(cbuf, ipcdev.ipc_base + 0x90, 16);
218		if (platform != MRST_CPU_CHIP_PENWELL) {
219			for (nc = 0, offset = 2; nc < count; nc++, offset += 3)
220				data[nc] = ipc_data_readb(offset);
221		} else {
222			for (nc = 0; nc < count; nc++)
223				data[nc] = ipc_data_readb(nc);
224		}
225	}
226	mutex_unlock(&ipclock);
227	return err;
228}
229
230/**
231 *	intel_scu_ipc_ioread8		-	read a word via the SCU
232 *	@addr: register on SCU
233 *	@data: return pointer for read byte
234 *
235 *	Read a single register. Returns 0 on success or an error code. All
236 *	locking between SCU accesses is handled for the caller.
237 *
238 *	This function may sleep.
239 */
240int intel_scu_ipc_ioread8(u16 addr, u8 *data)
241{
242	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
243}
244EXPORT_SYMBOL(intel_scu_ipc_ioread8);
245
246/**
247 *	intel_scu_ipc_ioread16		-	read a word via the SCU
248 *	@addr: register on SCU
249 *	@data: return pointer for read word
250 *
251 *	Read a register pair. Returns 0 on success or an error code. All
252 *	locking between SCU accesses is handled for the caller.
253 *
254 *	This function may sleep.
255 */
256int intel_scu_ipc_ioread16(u16 addr, u16 *data)
257{
258	u16 x[2] = {addr, addr + 1 };
259	return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
260}
261EXPORT_SYMBOL(intel_scu_ipc_ioread16);
262
263/**
264 *	intel_scu_ipc_ioread32		-	read a dword via the SCU
265 *	@addr: register on SCU
266 *	@data: return pointer for read dword
267 *
268 *	Read four registers. Returns 0 on success or an error code. All
269 *	locking between SCU accesses is handled for the caller.
270 *
271 *	This function may sleep.
272 */
273int intel_scu_ipc_ioread32(u16 addr, u32 *data)
274{
275	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
276	return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
277}
278EXPORT_SYMBOL(intel_scu_ipc_ioread32);
279
280/**
281 *	intel_scu_ipc_iowrite8		-	write a byte via the SCU
282 *	@addr: register on SCU
283 *	@data: byte to write
284 *
285 *	Write a single register. Returns 0 on success or an error code. All
286 *	locking between SCU accesses is handled for the caller.
287 *
288 *	This function may sleep.
289 */
290int intel_scu_ipc_iowrite8(u16 addr, u8 data)
291{
292	return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
293}
294EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
295
296/**
297 *	intel_scu_ipc_iowrite16		-	write a word via the SCU
298 *	@addr: register on SCU
299 *	@data: word to write
300 *
301 *	Write two registers. Returns 0 on success or an error code. All
302 *	locking between SCU accesses is handled for the caller.
303 *
304 *	This function may sleep.
305 */
306int intel_scu_ipc_iowrite16(u16 addr, u16 data)
307{
308	u16 x[2] = {addr, addr + 1 };
309	return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
310}
311EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
312
313/**
314 *	intel_scu_ipc_iowrite32		-	write a dword via the SCU
315 *	@addr: register on SCU
316 *	@data: dword to write
317 *
318 *	Write four registers. Returns 0 on success or an error code. All
319 *	locking between SCU accesses is handled for the caller.
320 *
321 *	This function may sleep.
322 */
323int intel_scu_ipc_iowrite32(u16 addr, u32 data)
324{
325	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
326	return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
327}
328EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
329
330/**
331 *	intel_scu_ipc_readvv		-	read a set of registers
332 *	@addr: register list
333 *	@data: bytes to return
334 *	@len: length of array
335 *
336 *	Read registers. Returns 0 on success or an error code. All
337 *	locking between SCU accesses is handled for the caller.
338 *
339 *	The largest array length permitted by the hardware is 5 items.
340 *
341 *	This function may sleep.
342 */
343int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
344{
345	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
346}
347EXPORT_SYMBOL(intel_scu_ipc_readv);
348
349/**
350 *	intel_scu_ipc_writev		-	write a set of registers
351 *	@addr: register list
352 *	@data: bytes to write
353 *	@len: length of array
354 *
355 *	Write registers. Returns 0 on success or an error code. All
356 *	locking between SCU accesses is handled for the caller.
357 *
358 *	The largest array length permitted by the hardware is 5 items.
359 *
360 *	This function may sleep.
361 *
362 */
363int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
364{
365	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
366}
367EXPORT_SYMBOL(intel_scu_ipc_writev);
368
369
370/**
371 *	intel_scu_ipc_update_register	-	r/m/w a register
372 *	@addr: register address
373 *	@bits: bits to update
374 *	@mask: mask of bits to update
375 *
376 *	Read-modify-write power control unit register. The first data argument
377 *	must be register value and second is mask value
378 *	mask is a bitmap that indicates which bits to update.
379 *	0 = masked. Don't modify this bit, 1 = modify this bit.
380 *	returns 0 on success or an error code.
381 *
382 *	This function may sleep. Locking between SCU accesses is handled
383 *	for the caller.
384 */
385int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
386{
387	u8 data[2] = { bits, mask };
388	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
389}
390EXPORT_SYMBOL(intel_scu_ipc_update_register);
391
392/**
393 *	intel_scu_ipc_simple_command	-	send a simple command
394 *	@cmd: command
395 *	@sub: sub type
396 *
397 *	Issue a simple command to the SCU. Do not use this interface if
398 *	you must then access data as any data values may be overwritten
399 *	by another SCU access by the time this function returns.
400 *
401 *	This function may sleep. Locking for SCU accesses is handled for
402 *	the caller.
403 */
404int intel_scu_ipc_simple_command(int cmd, int sub)
405{
406	int err;
407
408	mutex_lock(&ipclock);
409	if (ipcdev.pdev == NULL) {
410		mutex_unlock(&ipclock);
411		return -ENODEV;
412	}
413	ipc_command(sub << 12 | cmd);
414	err = busy_loop();
415	mutex_unlock(&ipclock);
416	return err;
417}
418EXPORT_SYMBOL(intel_scu_ipc_simple_command);
419
420/**
421 *	intel_scu_ipc_command	-	command with data
422 *	@cmd: command
423 *	@sub: sub type
424 *	@in: input data
425 *	@inlen: input length in dwords
426 *	@out: output data
427 *	@outlein: output length in dwords
428 *
429 *	Issue a command to the SCU which involves data transfers. Do the
430 *	data copies under the lock but leave it for the caller to interpret
431 */
432
433int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
434							u32 *out, int outlen)
435{
436	int i, err;
437
438	mutex_lock(&ipclock);
439	if (ipcdev.pdev == NULL) {
440		mutex_unlock(&ipclock);
441		return -ENODEV;
442	}
443
444	for (i = 0; i < inlen; i++)
445		ipc_data_writel(*in++, 4 * i);
446
447	ipc_command((inlen << 16) | (sub << 12) | cmd);
448	err = busy_loop();
449
450	for (i = 0; i < outlen; i++)
451		*out++ = ipc_data_readl(4 * i);
 
 
452
453	mutex_unlock(&ipclock);
454	return err;
455}
456EXPORT_SYMBOL(intel_scu_ipc_command);
457
458/*I2C commands */
459#define IPC_I2C_WRITE 1 /* I2C Write command */
460#define IPC_I2C_READ  2 /* I2C Read command */
461
462/**
463 *	intel_scu_ipc_i2c_cntrl		-	I2C read/write operations
464 *	@addr: I2C address + command bits
465 *	@data: data to read/write
466 *
467 *	Perform an an I2C read/write operation via the SCU. All locking is
468 *	handled for the caller. This function may sleep.
469 *
470 *	Returns an error code or 0 on success.
471 *
472 *	This has to be in the IPC driver for the locking.
473 */
474int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
475{
476	u32 cmd = 0;
477
478	mutex_lock(&ipclock);
479	if (ipcdev.pdev == NULL) {
480		mutex_unlock(&ipclock);
481		return -ENODEV;
482	}
483	cmd = (addr >> 24) & 0xFF;
484	if (cmd == IPC_I2C_READ) {
485		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
486		/* Write not getting updated without delay */
487		mdelay(1);
488		*data = readl(ipcdev.i2c_base + I2C_DATA_ADDR);
489	} else if (cmd == IPC_I2C_WRITE) {
490		writel(*data, ipcdev.i2c_base + I2C_DATA_ADDR);
491		mdelay(1);
492		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
493	} else {
494		dev_err(&ipcdev.pdev->dev,
495			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
496
497		mutex_unlock(&ipclock);
498		return -EIO;
499	}
500	mutex_unlock(&ipclock);
501	return 0;
502}
503EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
504
505#define IPC_FW_LOAD_ADDR 0xFFFC0000 /* Storage location for FW image */
506#define IPC_FW_UPDATE_MBOX_ADDR 0xFFFFDFF4 /* Mailbox between ipc and scu */
507#define IPC_MAX_FW_SIZE 262144 /* 256K storage size for loading the FW image */
508#define IPC_FW_MIP_HEADER_SIZE 2048 /* Firmware MIP header size */
509/* IPC inform SCU to get ready for update process */
510#define IPC_CMD_FW_UPDATE_READY  0x10FE
511/* IPC inform SCU to go for update process */
512#define IPC_CMD_FW_UPDATE_GO     0x20FE
513/* Status code for fw update */
514#define IPC_FW_UPDATE_SUCCESS	0x444f4e45 /* Status code 'DONE' */
515#define IPC_FW_UPDATE_BADN	0x4241444E /* Status code 'BADN' */
516#define IPC_FW_TXHIGH		0x54784849 /* Status code 'IPC_FW_TXHIGH' */
517#define IPC_FW_TXLOW		0x54784c4f /* Status code 'IPC_FW_TXLOW' */
518
519struct fw_update_mailbox {
520	u32    status;
521	u32    scu_flag;
522	u32    driver_flag;
523};
524
525
526/**
527 *	intel_scu_ipc_fw_update	-	 Firmware update utility
528 *	@buffer: firmware buffer
529 *	@length: size of firmware buffer
530 *
531 *	This function provides an interface to load the firmware into
532 *	the SCU. Returns 0 on success or -1 on failure
533 */
534int intel_scu_ipc_fw_update(u8 *buffer, u32 length)
535{
536	void __iomem *fw_update_base;
537	struct fw_update_mailbox __iomem *mailbox = NULL;
538	int retry_cnt = 0;
539	u32 status;
540
541	mutex_lock(&ipclock);
542	fw_update_base = ioremap_nocache(IPC_FW_LOAD_ADDR, (128*1024));
543	if (fw_update_base == NULL) {
544		mutex_unlock(&ipclock);
545		return -ENOMEM;
546	}
547	mailbox = ioremap_nocache(IPC_FW_UPDATE_MBOX_ADDR,
548					sizeof(struct fw_update_mailbox));
549	if (mailbox == NULL) {
550		iounmap(fw_update_base);
551		mutex_unlock(&ipclock);
552		return -ENOMEM;
553	}
554
555	ipc_command(IPC_CMD_FW_UPDATE_READY);
556
557	/* Intitialize mailbox */
558	writel(0, &mailbox->status);
559	writel(0, &mailbox->scu_flag);
560	writel(0, &mailbox->driver_flag);
561
562	/* Driver copies the 2KB MIP header to SRAM at 0xFFFC0000*/
563	memcpy_toio(fw_update_base, buffer, 0x800);
564
565	/* Driver sends "FW Update" IPC command (CMD_ID 0xFE; MSG_ID 0x02).
566	* Upon receiving this command, SCU will write the 2K MIP header
567	* from 0xFFFC0000 into NAND.
568	* SCU will write a status code into the Mailbox, and then set scu_flag.
569	*/
570
571	ipc_command(IPC_CMD_FW_UPDATE_GO);
572
573	/*Driver stalls until scu_flag is set */
574	while (readl(&mailbox->scu_flag) != 1) {
575		rmb();
576		mdelay(1);
577	}
578
579	/* Driver checks Mailbox status.
580	 * If the status is 'BADN', then abort (bad NAND).
581	 * If the status is 'IPC_FW_TXLOW', then continue.
582	 */
583	while (readl(&mailbox->status) != IPC_FW_TXLOW) {
584		rmb();
585		mdelay(10);
586	}
587	mdelay(10);
588
589update_retry:
590	if (retry_cnt > 5)
591		goto update_end;
592
593	if (readl(&mailbox->status) != IPC_FW_TXLOW)
594		goto update_end;
595	buffer = buffer + 0x800;
596	memcpy_toio(fw_update_base, buffer, 0x20000);
597	writel(1, &mailbox->driver_flag);
598	while (readl(&mailbox->scu_flag) == 1) {
599		rmb();
600		mdelay(1);
601	}
602
603	/* check for 'BADN' */
604	if (readl(&mailbox->status) == IPC_FW_UPDATE_BADN)
605		goto update_end;
606
607	while (readl(&mailbox->status) != IPC_FW_TXHIGH) {
608		rmb();
609		mdelay(10);
610	}
611	mdelay(10);
612
613	if (readl(&mailbox->status) != IPC_FW_TXHIGH)
614		goto update_end;
615
616	buffer = buffer + 0x20000;
617	memcpy_toio(fw_update_base, buffer, 0x20000);
618	writel(0, &mailbox->driver_flag);
619
620	while (mailbox->scu_flag == 0) {
621		rmb();
622		mdelay(1);
623	}
624
625	/* check for 'BADN' */
626	if (readl(&mailbox->status) == IPC_FW_UPDATE_BADN)
627		goto update_end;
628
629	if (readl(&mailbox->status) == IPC_FW_TXLOW) {
630		++retry_cnt;
631		goto update_retry;
632	}
633
634update_end:
635	status = readl(&mailbox->status);
636
637	iounmap(fw_update_base);
638	iounmap(mailbox);
639	mutex_unlock(&ipclock);
640
641	if (status == IPC_FW_UPDATE_SUCCESS)
642		return 0;
643	return -EIO;
644}
645EXPORT_SYMBOL(intel_scu_ipc_fw_update);
646
647/*
648 * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
649 * When ioc bit is set to 1, caller api must wait for interrupt handler called
650 * which in turn unlocks the caller api. Currently this is not used
651 *
652 * This is edge triggered so we need take no action to clear anything
653 */
654static irqreturn_t ioc(int irq, void *dev_id)
655{
 
 
 
656	return IRQ_HANDLED;
657}
658
659/**
660 *	ipc_probe	-	probe an Intel SCU IPC
661 *	@dev: the PCI device matching
662 *	@id: entry in the match table
663 *
664 *	Enable and install an intel SCU IPC. This appears in the PCI space
665 *	but uses some hard coded addresses as well.
666 */
667static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id)
668{
669	int err;
 
670	resource_size_t pci_resource;
671
672	if (ipcdev.pdev)		/* We support only one SCU */
673		return -EBUSY;
674
 
 
675	ipcdev.pdev = pci_dev_get(dev);
 
676
677	err = pci_enable_device(dev);
678	if (err)
679		return err;
680
681	err = pci_request_regions(dev, "intel_scu_ipc");
682	if (err)
683		return err;
684
685	pci_resource = pci_resource_start(dev, 0);
686	if (!pci_resource)
687		return -ENOMEM;
688
 
 
689	if (request_irq(dev->irq, ioc, 0, "intel_scu_ipc", &ipcdev))
690		return -EBUSY;
691
692	ipcdev.ipc_base = ioremap_nocache(IPC_BASE_ADDR, IPC_MAX_ADDR);
693	if (!ipcdev.ipc_base)
694		return -ENOMEM;
695
696	ipcdev.i2c_base = ioremap_nocache(IPC_I2C_BASE, IPC_I2C_MAX_ADDR);
697	if (!ipcdev.i2c_base) {
698		iounmap(ipcdev.ipc_base);
699		return -ENOMEM;
700	}
701
702	intel_scu_devices_create();
703
704	return 0;
705}
706
707/**
708 *	ipc_remove	-	remove a bound IPC device
709 *	@pdev: PCI device
710 *
711 *	In practice the SCU is not removable but this function is also
712 *	called for each device on a module unload or cleanup which is the
713 *	path that will get used.
714 *
715 *	Free up the mappings and release the PCI resources
716 */
717static void ipc_remove(struct pci_dev *pdev)
718{
719	free_irq(pdev->irq, &ipcdev);
720	pci_release_regions(pdev);
721	pci_dev_put(ipcdev.pdev);
722	iounmap(ipcdev.ipc_base);
723	iounmap(ipcdev.i2c_base);
724	ipcdev.pdev = NULL;
725	intel_scu_devices_destroy();
726}
727
728static DEFINE_PCI_DEVICE_TABLE(pci_ids) = {
729	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080e)},
730	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x082a)},
731	{ 0,}
 
 
 
 
 
 
 
 
 
 
 
 
732};
733MODULE_DEVICE_TABLE(pci, pci_ids);
734
735static struct pci_driver ipc_driver = {
736	.name = "intel_scu_ipc",
737	.id_table = pci_ids,
738	.probe = ipc_probe,
739	.remove = ipc_remove,
740};
741
742
743static int __init intel_scu_ipc_init(void)
744{
745	platform = mrst_identify_cpu();
746	if (platform == 0)
747		return -ENODEV;
748	return  pci_register_driver(&ipc_driver);
749}
750
751static void __exit intel_scu_ipc_exit(void)
752{
753	pci_unregister_driver(&ipc_driver);
754}
755
756MODULE_AUTHOR("Sreedhara DS <sreedhara.ds@intel.com>");
757MODULE_DESCRIPTION("Intel SCU IPC driver");
758MODULE_LICENSE("GPL");
759
760module_init(intel_scu_ipc_init);
761module_exit(intel_scu_ipc_exit);
v3.15
  1/*
  2 * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism
  3 *
  4 * (C) Copyright 2008-2010 Intel Corporation
  5 * Author: Sreedhara DS (sreedhara.ds@intel.com)
  6 *
  7 * This program is free software; you can redistribute it and/or
  8 * modify it under the terms of the GNU General Public License
  9 * as published by the Free Software Foundation; version 2
 10 * of the License.
 11 *
 12 * SCU running in ARC processor communicates with other entity running in IA
 13 * core through IPC mechanism which in turn messaging between IA core ad SCU.
 14 * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and
 15 * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with
 16 * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC)
 17 * along with other APIs.
 18 */
 19#include <linux/delay.h>
 20#include <linux/errno.h>
 21#include <linux/init.h>
 22#include <linux/device.h>
 23#include <linux/pm.h>
 24#include <linux/pci.h>
 25#include <linux/interrupt.h>
 26#include <linux/sfi.h>
 27#include <linux/module.h>
 28#include <asm/intel-mid.h>
 29#include <asm/intel_scu_ipc.h>
 30
 31/* IPC defines the following message types */
 32#define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
 33#define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
 34#define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
 35#define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
 36#define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
 37
 38/* Command id associated with message IPCMSG_PCNTRL */
 39#define IPC_CMD_PCNTRL_W      0 /* Register write */
 40#define IPC_CMD_PCNTRL_R      1 /* Register read */
 41#define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
 42
 43/*
 44 * IPC register summary
 45 *
 46 * IPC register blocks are memory mapped at fixed address of 0xFF11C000
 47 * To read or write information to the SCU, driver writes to IPC-1 memory
 48 * mapped registers (base address 0xFF11C000). The following is the IPC
 49 * mechanism
 50 *
 51 * 1. IA core cDMI interface claims this transaction and converts it to a
 52 *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
 53 *
 54 * 2. South Complex cDMI block receives this message and writes it to
 55 *    the IPC-1 register block, causing an interrupt to the SCU
 56 *
 57 * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
 58 *    message handler is called within firmware.
 59 */
 60
 
 
 61#define IPC_WWBUF_SIZE    20		/* IPC Write buffer Size */
 62#define IPC_RWBUF_SIZE    20		/* IPC Read buffer Size */
 63#define IPC_IOC	          0x100		/* IPC command register IOC bit */
 64
 65#define PCI_DEVICE_ID_LINCROFT		0x082a
 66#define PCI_DEVICE_ID_PENWELL		0x080e
 67#define PCI_DEVICE_ID_CLOVERVIEW	0x08ea
 68#define PCI_DEVICE_ID_TANGIER		0x11a0
 69
 70/* intel scu ipc driver data*/
 71struct intel_scu_ipc_pdata_t {
 72	u32 ipc_base;
 73	u32 i2c_base;
 74	u32 ipc_len;
 75	u32 i2c_len;
 76	u8 irq_mode;
 77};
 78
 79static struct intel_scu_ipc_pdata_t intel_scu_ipc_lincroft_pdata = {
 80	.ipc_base = 0xff11c000,
 81	.i2c_base = 0xff12b000,
 82	.ipc_len = 0x100,
 83	.i2c_len = 0x10,
 84	.irq_mode = 0,
 85};
 86
 87/* Penwell and Cloverview */
 88static struct intel_scu_ipc_pdata_t intel_scu_ipc_penwell_pdata = {
 89	.ipc_base = 0xff11c000,
 90	.i2c_base = 0xff12b000,
 91	.ipc_len = 0x100,
 92	.i2c_len = 0x10,
 93	.irq_mode = 1,
 94};
 95
 96static struct intel_scu_ipc_pdata_t intel_scu_ipc_tangier_pdata = {
 97	.ipc_base = 0xff009000,
 98	.i2c_base  = 0xff00d000,
 99	.ipc_len  = 0x100,
100	.i2c_len = 0x10,
101	.irq_mode = 0,
102};
103
104static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id);
105static void ipc_remove(struct pci_dev *pdev);
106
107struct intel_scu_ipc_dev {
108	struct pci_dev *pdev;
109	void __iomem *ipc_base;
110	void __iomem *i2c_base;
111	struct completion cmd_complete;
112	u8 irq_mode;
113};
114
115static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
116
117static int platform;		/* Platform type */
118
119/*
120 * IPC Read Buffer (Read Only):
121 * 16 byte buffer for receiving data from SCU, if IPC command
122 * processing results in response data
123 */
124#define IPC_READ_BUFFER		0x90
125
126#define IPC_I2C_CNTRL_ADDR	0
127#define I2C_DATA_ADDR		0x04
128
129static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
130
131/*
132 * Command Register (Write Only):
133 * A write to this register results in an interrupt to the SCU core processor
134 * Format:
135 * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
136 */
137static inline void ipc_command(u32 cmd) /* Send ipc command */
138{
139	if (ipcdev.irq_mode) {
140		reinit_completion(&ipcdev.cmd_complete);
141		writel(cmd | IPC_IOC, ipcdev.ipc_base);
142	}
143	writel(cmd, ipcdev.ipc_base);
144}
145
146/*
147 * IPC Write Buffer (Write Only):
148 * 16-byte buffer for sending data associated with IPC command to
149 * SCU. Size of the data is specified in the IPC_COMMAND_REG register
150 */
151static inline void ipc_data_writel(u32 data, u32 offset) /* Write ipc data */
152{
153	writel(data, ipcdev.ipc_base + 0x80 + offset);
154}
155
156/*
157 * Status Register (Read Only):
158 * Driver will read this register to get the ready/busy status of the IPC
159 * block and error status of the IPC command that was just processed by SCU
160 * Format:
161 * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
162 */
163
164static inline u8 ipc_read_status(void)
165{
166	return __raw_readl(ipcdev.ipc_base + 0x04);
167}
168
169static inline u8 ipc_data_readb(u32 offset) /* Read ipc byte data */
170{
171	return readb(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
172}
173
174static inline u32 ipc_data_readl(u32 offset) /* Read ipc u32 data */
175{
176	return readl(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
177}
178
179static inline int busy_loop(void) /* Wait till scu status is busy */
180{
181	u32 status = 0;
182	u32 loop_count = 0;
183
184	status = ipc_read_status();
185	while (status & 1) {
186		udelay(1); /* scu processing time is in few u secods */
187		status = ipc_read_status();
188		loop_count++;
189		/* break if scu doesn't reset busy bit after huge retry */
190		if (loop_count > 100000) {
191			dev_err(&ipcdev.pdev->dev, "IPC timed out");
192			return -ETIMEDOUT;
193		}
194	}
195	if ((status >> 1) & 1)
196		return -EIO;
197
198	return 0;
199}
200
201/* Wait till ipc ioc interrupt is received or timeout in 3 HZ */
202static inline int ipc_wait_for_interrupt(void)
203{
204	int status;
205
206	if (!wait_for_completion_timeout(&ipcdev.cmd_complete, 3 * HZ)) {
207		struct device *dev = &ipcdev.pdev->dev;
208		dev_err(dev, "IPC timed out\n");
209		return -ETIMEDOUT;
210	}
211
212	status = ipc_read_status();
213
214	if ((status >> 1) & 1)
215		return -EIO;
216
217	return 0;
218}
219
220int intel_scu_ipc_check_status(void)
221{
222	return ipcdev.irq_mode ? ipc_wait_for_interrupt() : busy_loop();
223}
224
225/* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
226static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
227{
228	int nc;
229	u32 offset = 0;
230	int err;
231	u8 cbuf[IPC_WWBUF_SIZE] = { };
232	u32 *wbuf = (u32 *)&cbuf;
233
234	mutex_lock(&ipclock);
235
236	memset(cbuf, 0, sizeof(cbuf));
237
238	if (ipcdev.pdev == NULL) {
239		mutex_unlock(&ipclock);
240		return -ENODEV;
241	}
242
243	for (nc = 0; nc < count; nc++, offset += 2) {
244		cbuf[offset] = addr[nc];
245		cbuf[offset + 1] = addr[nc] >> 8;
246	}
247
248	if (id == IPC_CMD_PCNTRL_R) {
249		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
250			ipc_data_writel(wbuf[nc], offset);
251		ipc_command((count*2) << 16 |  id << 12 | 0 << 8 | op);
252	} else if (id == IPC_CMD_PCNTRL_W) {
253		for (nc = 0; nc < count; nc++, offset += 1)
254			cbuf[offset] = data[nc];
255		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
256			ipc_data_writel(wbuf[nc], offset);
257		ipc_command((count*3) << 16 |  id << 12 | 0 << 8 | op);
258	} else if (id == IPC_CMD_PCNTRL_M) {
259		cbuf[offset] = data[0];
260		cbuf[offset + 1] = data[1];
261		ipc_data_writel(wbuf[0], 0); /* Write wbuff */
262		ipc_command(4 << 16 |  id << 12 | 0 << 8 | op);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
263	}
264
265	err = intel_scu_ipc_check_status();
266	if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
267		/* Workaround: values are read as 0 without memcpy_fromio */
268		memcpy_fromio(cbuf, ipcdev.ipc_base + 0x90, 16);
269		for (nc = 0; nc < count; nc++)
270			data[nc] = ipc_data_readb(nc);
 
 
 
 
 
271	}
272	mutex_unlock(&ipclock);
273	return err;
274}
275
276/**
277 *	intel_scu_ipc_ioread8		-	read a word via the SCU
278 *	@addr: register on SCU
279 *	@data: return pointer for read byte
280 *
281 *	Read a single register. Returns 0 on success or an error code. All
282 *	locking between SCU accesses is handled for the caller.
283 *
284 *	This function may sleep.
285 */
286int intel_scu_ipc_ioread8(u16 addr, u8 *data)
287{
288	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
289}
290EXPORT_SYMBOL(intel_scu_ipc_ioread8);
291
292/**
293 *	intel_scu_ipc_ioread16		-	read a word via the SCU
294 *	@addr: register on SCU
295 *	@data: return pointer for read word
296 *
297 *	Read a register pair. Returns 0 on success or an error code. All
298 *	locking between SCU accesses is handled for the caller.
299 *
300 *	This function may sleep.
301 */
302int intel_scu_ipc_ioread16(u16 addr, u16 *data)
303{
304	u16 x[2] = {addr, addr + 1 };
305	return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
306}
307EXPORT_SYMBOL(intel_scu_ipc_ioread16);
308
309/**
310 *	intel_scu_ipc_ioread32		-	read a dword via the SCU
311 *	@addr: register on SCU
312 *	@data: return pointer for read dword
313 *
314 *	Read four registers. Returns 0 on success or an error code. All
315 *	locking between SCU accesses is handled for the caller.
316 *
317 *	This function may sleep.
318 */
319int intel_scu_ipc_ioread32(u16 addr, u32 *data)
320{
321	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
322	return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
323}
324EXPORT_SYMBOL(intel_scu_ipc_ioread32);
325
326/**
327 *	intel_scu_ipc_iowrite8		-	write a byte via the SCU
328 *	@addr: register on SCU
329 *	@data: byte to write
330 *
331 *	Write a single register. Returns 0 on success or an error code. All
332 *	locking between SCU accesses is handled for the caller.
333 *
334 *	This function may sleep.
335 */
336int intel_scu_ipc_iowrite8(u16 addr, u8 data)
337{
338	return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
339}
340EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
341
342/**
343 *	intel_scu_ipc_iowrite16		-	write a word via the SCU
344 *	@addr: register on SCU
345 *	@data: word to write
346 *
347 *	Write two registers. Returns 0 on success or an error code. All
348 *	locking between SCU accesses is handled for the caller.
349 *
350 *	This function may sleep.
351 */
352int intel_scu_ipc_iowrite16(u16 addr, u16 data)
353{
354	u16 x[2] = {addr, addr + 1 };
355	return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
356}
357EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
358
359/**
360 *	intel_scu_ipc_iowrite32		-	write a dword via the SCU
361 *	@addr: register on SCU
362 *	@data: dword to write
363 *
364 *	Write four registers. Returns 0 on success or an error code. All
365 *	locking between SCU accesses is handled for the caller.
366 *
367 *	This function may sleep.
368 */
369int intel_scu_ipc_iowrite32(u16 addr, u32 data)
370{
371	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
372	return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
373}
374EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
375
376/**
377 *	intel_scu_ipc_readvv		-	read a set of registers
378 *	@addr: register list
379 *	@data: bytes to return
380 *	@len: length of array
381 *
382 *	Read registers. Returns 0 on success or an error code. All
383 *	locking between SCU accesses is handled for the caller.
384 *
385 *	The largest array length permitted by the hardware is 5 items.
386 *
387 *	This function may sleep.
388 */
389int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
390{
391	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
392}
393EXPORT_SYMBOL(intel_scu_ipc_readv);
394
395/**
396 *	intel_scu_ipc_writev		-	write a set of registers
397 *	@addr: register list
398 *	@data: bytes to write
399 *	@len: length of array
400 *
401 *	Write registers. Returns 0 on success or an error code. All
402 *	locking between SCU accesses is handled for the caller.
403 *
404 *	The largest array length permitted by the hardware is 5 items.
405 *
406 *	This function may sleep.
407 *
408 */
409int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
410{
411	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
412}
413EXPORT_SYMBOL(intel_scu_ipc_writev);
414
415
416/**
417 *	intel_scu_ipc_update_register	-	r/m/w a register
418 *	@addr: register address
419 *	@bits: bits to update
420 *	@mask: mask of bits to update
421 *
422 *	Read-modify-write power control unit register. The first data argument
423 *	must be register value and second is mask value
424 *	mask is a bitmap that indicates which bits to update.
425 *	0 = masked. Don't modify this bit, 1 = modify this bit.
426 *	returns 0 on success or an error code.
427 *
428 *	This function may sleep. Locking between SCU accesses is handled
429 *	for the caller.
430 */
431int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
432{
433	u8 data[2] = { bits, mask };
434	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
435}
436EXPORT_SYMBOL(intel_scu_ipc_update_register);
437
438/**
439 *	intel_scu_ipc_simple_command	-	send a simple command
440 *	@cmd: command
441 *	@sub: sub type
442 *
443 *	Issue a simple command to the SCU. Do not use this interface if
444 *	you must then access data as any data values may be overwritten
445 *	by another SCU access by the time this function returns.
446 *
447 *	This function may sleep. Locking for SCU accesses is handled for
448 *	the caller.
449 */
450int intel_scu_ipc_simple_command(int cmd, int sub)
451{
452	int err;
453
454	mutex_lock(&ipclock);
455	if (ipcdev.pdev == NULL) {
456		mutex_unlock(&ipclock);
457		return -ENODEV;
458	}
459	ipc_command(sub << 12 | cmd);
460	err = intel_scu_ipc_check_status();
461	mutex_unlock(&ipclock);
462	return err;
463}
464EXPORT_SYMBOL(intel_scu_ipc_simple_command);
465
466/**
467 *	intel_scu_ipc_command	-	command with data
468 *	@cmd: command
469 *	@sub: sub type
470 *	@in: input data
471 *	@inlen: input length in dwords
472 *	@out: output data
473 *	@outlein: output length in dwords
474 *
475 *	Issue a command to the SCU which involves data transfers. Do the
476 *	data copies under the lock but leave it for the caller to interpret
477 */
478
479int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
480							u32 *out, int outlen)
481{
482	int i, err;
483
484	mutex_lock(&ipclock);
485	if (ipcdev.pdev == NULL) {
486		mutex_unlock(&ipclock);
487		return -ENODEV;
488	}
489
490	for (i = 0; i < inlen; i++)
491		ipc_data_writel(*in++, 4 * i);
492
493	ipc_command((inlen << 16) | (sub << 12) | cmd);
494	err = intel_scu_ipc_check_status();
495
496	if (!err) {
497		for (i = 0; i < outlen; i++)
498			*out++ = ipc_data_readl(4 * i);
499	}
500
501	mutex_unlock(&ipclock);
502	return err;
503}
504EXPORT_SYMBOL(intel_scu_ipc_command);
505
506/*I2C commands */
507#define IPC_I2C_WRITE 1 /* I2C Write command */
508#define IPC_I2C_READ  2 /* I2C Read command */
509
510/**
511 *	intel_scu_ipc_i2c_cntrl		-	I2C read/write operations
512 *	@addr: I2C address + command bits
513 *	@data: data to read/write
514 *
515 *	Perform an an I2C read/write operation via the SCU. All locking is
516 *	handled for the caller. This function may sleep.
517 *
518 *	Returns an error code or 0 on success.
519 *
520 *	This has to be in the IPC driver for the locking.
521 */
522int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
523{
524	u32 cmd = 0;
525
526	mutex_lock(&ipclock);
527	if (ipcdev.pdev == NULL) {
528		mutex_unlock(&ipclock);
529		return -ENODEV;
530	}
531	cmd = (addr >> 24) & 0xFF;
532	if (cmd == IPC_I2C_READ) {
533		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
534		/* Write not getting updated without delay */
535		mdelay(1);
536		*data = readl(ipcdev.i2c_base + I2C_DATA_ADDR);
537	} else if (cmd == IPC_I2C_WRITE) {
538		writel(*data, ipcdev.i2c_base + I2C_DATA_ADDR);
539		mdelay(1);
540		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
541	} else {
542		dev_err(&ipcdev.pdev->dev,
543			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
544
545		mutex_unlock(&ipclock);
546		return -EIO;
547	}
548	mutex_unlock(&ipclock);
549	return 0;
550}
551EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
552
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
553/*
554 * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
555 * When ioc bit is set to 1, caller api must wait for interrupt handler called
556 * which in turn unlocks the caller api. Currently this is not used
557 *
558 * This is edge triggered so we need take no action to clear anything
559 */
560static irqreturn_t ioc(int irq, void *dev_id)
561{
562	if (ipcdev.irq_mode)
563		complete(&ipcdev.cmd_complete);
564
565	return IRQ_HANDLED;
566}
567
568/**
569 *	ipc_probe	-	probe an Intel SCU IPC
570 *	@dev: the PCI device matching
571 *	@id: entry in the match table
572 *
573 *	Enable and install an intel SCU IPC. This appears in the PCI space
574 *	but uses some hard coded addresses as well.
575 */
576static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id)
577{
578	int err;
579	struct intel_scu_ipc_pdata_t *pdata;
580	resource_size_t pci_resource;
581
582	if (ipcdev.pdev)		/* We support only one SCU */
583		return -EBUSY;
584
585	pdata = (struct intel_scu_ipc_pdata_t *)id->driver_data;
586
587	ipcdev.pdev = pci_dev_get(dev);
588	ipcdev.irq_mode = pdata->irq_mode;
589
590	err = pci_enable_device(dev);
591	if (err)
592		return err;
593
594	err = pci_request_regions(dev, "intel_scu_ipc");
595	if (err)
596		return err;
597
598	pci_resource = pci_resource_start(dev, 0);
599	if (!pci_resource)
600		return -ENOMEM;
601
602	init_completion(&ipcdev.cmd_complete);
603
604	if (request_irq(dev->irq, ioc, 0, "intel_scu_ipc", &ipcdev))
605		return -EBUSY;
606
607	ipcdev.ipc_base = ioremap_nocache(pdata->ipc_base, pdata->ipc_len);
608	if (!ipcdev.ipc_base)
609		return -ENOMEM;
610
611	ipcdev.i2c_base = ioremap_nocache(pdata->i2c_base, pdata->i2c_len);
612	if (!ipcdev.i2c_base) {
613		iounmap(ipcdev.ipc_base);
614		return -ENOMEM;
615	}
616
617	intel_scu_devices_create();
618
619	return 0;
620}
621
622/**
623 *	ipc_remove	-	remove a bound IPC device
624 *	@pdev: PCI device
625 *
626 *	In practice the SCU is not removable but this function is also
627 *	called for each device on a module unload or cleanup which is the
628 *	path that will get used.
629 *
630 *	Free up the mappings and release the PCI resources
631 */
632static void ipc_remove(struct pci_dev *pdev)
633{
634	free_irq(pdev->irq, &ipcdev);
635	pci_release_regions(pdev);
636	pci_dev_put(ipcdev.pdev);
637	iounmap(ipcdev.ipc_base);
638	iounmap(ipcdev.i2c_base);
639	ipcdev.pdev = NULL;
640	intel_scu_devices_destroy();
641}
642
643static DEFINE_PCI_DEVICE_TABLE(pci_ids) = {
644	{
645		PCI_VDEVICE(INTEL, PCI_DEVICE_ID_LINCROFT),
646		(kernel_ulong_t)&intel_scu_ipc_lincroft_pdata,
647	}, {
648		PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PENWELL),
649		(kernel_ulong_t)&intel_scu_ipc_penwell_pdata,
650	}, {
651		PCI_VDEVICE(INTEL, PCI_DEVICE_ID_CLOVERVIEW),
652		(kernel_ulong_t)&intel_scu_ipc_penwell_pdata,
653	}, {
654		PCI_VDEVICE(INTEL, PCI_DEVICE_ID_TANGIER),
655		(kernel_ulong_t)&intel_scu_ipc_tangier_pdata,
656	}, {
657		0,
658	}
659};
660MODULE_DEVICE_TABLE(pci, pci_ids);
661
662static struct pci_driver ipc_driver = {
663	.name = "intel_scu_ipc",
664	.id_table = pci_ids,
665	.probe = ipc_probe,
666	.remove = ipc_remove,
667};
668
669
670static int __init intel_scu_ipc_init(void)
671{
672	platform = intel_mid_identify_cpu();
673	if (platform == 0)
674		return -ENODEV;
675	return  pci_register_driver(&ipc_driver);
676}
677
678static void __exit intel_scu_ipc_exit(void)
679{
680	pci_unregister_driver(&ipc_driver);
681}
682
683MODULE_AUTHOR("Sreedhara DS <sreedhara.ds@intel.com>");
684MODULE_DESCRIPTION("Intel SCU IPC driver");
685MODULE_LICENSE("GPL");
686
687module_init(intel_scu_ipc_init);
688module_exit(intel_scu_ipc_exit);