xref: /freebsd/sys/dev/ichiic/ig4_reg.h (revision 65b71c48d226f3ef3eb1c4452dccc678a7d2ac96)
1 /*
2  * Copyright (c) 2014 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com> and was subsequently ported
6  * to FreeBSD by Michael Gmelin <freebsd@grem.de>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  * 3. Neither the name of The DragonFly Project nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific, prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
36  */
37 /*
38  * Intel fourth generation mobile cpus integrated I2C device.
39  *
40  * Datasheet reference:  Section 22.
41  *
42  * http://www.intel.com/content/www/us/en/processors/core/4th-gen-core-family-mobile-i-o-datasheet.html?wapkw=datasheets+4th+generation
43  *
44  * This is a from-scratch driver under the BSD license using the Intel data
45  * sheet and the linux driver for reference.  All code is freshly written
46  * without referencing the linux driver code.  However, during testing
47  * I am also using the linux driver code as a reference to help resolve any
48  * issues that come.  These will be specifically documented in the code.
49  *
50  * Please see protocol notes in section 5.21.  This controller is an I2C
51  * master only and cannot act as a slave.  The IO voltage should be set by
52  * the BIOS.  Standard (100Kb/s) and Fast (400Kb/s) and fast mode plus
53  * (1MB/s) is supported.  High speed mode (3.4 MB/s) is NOT supported.
54  */
55 
56 #ifndef _BUS_SMBUS_INTELGEN4_IG4_REG_H_
57 #define _BUS_SMBUS_INTELGEN4_IG4_REG_H_
58 
59 /*
60  * 22.2 MMIO registers can be accessed through BAR0 in PCI mode or through
61  *	BAR1 when in ACPI mode.
62  *
63  *	Register width is 32-bits
64  *
65  * 22.2 Default Values on device reset are 0 except as specified here:
66  *	TAR_ADD		0x00000055
67  *	SS_SCL_HCNT	0x00000264
68  *	SS_SCL_LCNT	0x000002C2
69  *	FS_SCL_HCNT	0x0000006E
70  *	FS_SCL_LCNT	0x000000CF
71  *	INTR_MASK	0x000008FF
72  *	I2C_STA		0x00000006
73  *	SDA_HOLD	0x00000001
74  *	SDA_SETUP	0x00000064
75  *	COMP_PARAM1	0x00FFFF6E
76  *	COMP_VER	0x3131352A
77  */
78 
79 #define IG4_REG_CTL		0x0000	/* RW	Control Register */
80 #define IG4_REG_TAR_ADD		0x0004	/* RW	Target Address */
81 #define IG4_REG_DATA_CMD	0x0010	/* RW	Data Buffer and Command */
82 #define IG4_REG_SS_SCL_HCNT	0x0014	/* RW	Std Speed clock High Count */
83 #define IG4_REG_SS_SCL_LCNT	0x0018	/* RW	Std Speed clock Low Count */
84 #define IG4_REG_FS_SCL_HCNT	0x001C	/* RW	Fast Speed clock High Count */
85 #define IG4_REG_FS_SCL_LCNT	0x0020	/* RW	Fast Speed clock Low Count */
86 #define IG4_REG_INTR_STAT	0x002C	/* RO	Interrupt Status */
87 #define IG4_REG_INTR_MASK	0x0030	/* RW	Interrupt Mask */
88 #define IG4_REG_RAW_INTR_STAT	0x0034	/* RO	Raw Interrupt Status */
89 #define IG4_REG_RX_TL		0x0038	/* RW	Receive FIFO Threshold */
90 #define IG4_REG_TX_TL		0x003C	/* RW	Transmit FIFO Threshold */
91 #define IG4_REG_CLR_INTR	0x0040	/* RO	Clear Interrupt */
92 #define IG4_REG_CLR_RX_UNDER	0x0044	/* RO	Clear RX_Under Interrupt */
93 #define IG4_REG_CLR_RX_OVER	0x0048	/* RO	Clear RX_Over Interrupt */
94 #define IG4_REG_CLR_TX_OVER	0x004C	/* RO	Clear TX_Over Interrupt */
95 #define IG4_REG_CLR_TX_ABORT	0x0054	/* RO	Clear TX_Abort Interrupt */
96 #define IG4_REG_CLR_ACTIVITY	0x005C	/* RO	Clear Activity Interrupt */
97 #define IG4_REG_CLR_STOP_DET	0x0060	/* RO	Clear STOP Detection Int */
98 #define IG4_REG_CLR_START_DET	0x0064	/* RO	Clear START Detection Int */
99 #define IG4_REG_CLR_GEN_CALL	0x0068	/* RO	Clear General Call Interrupt */
100 #define IG4_REG_I2C_EN		0x006C	/* RW	I2C Enable */
101 #define IG4_REG_I2C_STA		0x0070	/* RO	I2C Status */
102 #define IG4_REG_TXFLR		0x0074	/* RO	Transmit FIFO Level */
103 #define IG4_REG_RXFLR		0x0078	/* RO	Receive FIFO Level */
104 #define IG4_REG_SDA_HOLD	0x007C	/* RW	SDA Hold Time Length */
105 #define IG4_REG_TX_ABRT_SOURCE	0x0080	/* RO	Transmit Abort Source */
106 #define IG4_REG_SLV_DATA_NACK	0x0084	/* RW	General Slave Data NACK */
107 #define IG4_REG_DMA_CTRL	0x0088	/* RW	DMA Control */
108 #define IG4_REG_DMA_TDLR	0x008C	/* RW	DMA Transmit Data Level */
109 #define IG4_REG_DMA_RDLR	0x0090	/* RW	DMA Receive Data Level */
110 #define IG4_REG_SDA_SETUP	0x0094	/* RW	SDA Setup */
111 #define IG4_REG_ENABLE_STATUS	0x009C	/* RO	Enable Status */
112 #define IG4_REG_COMP_PARAM1	0x00F4	/* RO	Component Parameter */
113 #define IG4_REG_COMP_VER	0x00F8	/* RO	Component Version */
114 #define IG4_REG_COMP_TYPE	0x00FC	/* RO	Probe width/endian? (linux) */
115 #define IG4_REG_CLK_PARMS	0x0800	/* RW	Clock Parameters */
116 #define IG4_REG_RESETS		0x0804	/* RW	Reset Register */
117 #define IG4_REG_GENERAL		0x0808	/* RW	General Register */
118 #define IG4_REG_SW_LTR_VALUE	0x0810	/* RW	SW LTR Value */
119 #define IG4_REG_AUTO_LTR_VALUE	0x0814	/* RW	Auto LTR Value */
120 
121 /*
122  * CTL - Control Register 		22.2.1
123  *	 Default Value: 0x0000007F.
124  *
125  *	RESTARTEN	- RW Restart Enable
126  *	10BIT		- RW Controller operates in 10-bit mode, else 7-bit
127  *
128  * NOTE: When restart is disabled the controller is incapable of
129  *	 performing the following functions:
130  *
131  *		 Sending a START Byte
132  *		 Performing any high-speed mode op
133  *		 Performing direction changes in combined format mode
134  *		 Performing a read operation with a 10-bit address
135  *
136  *	 Attempting to perform the above operations will result in the
137  *	 TX_ABORT bit being set in RAW_INTR_STAT.
138  */
139 #define IG4_CTL_SLAVE_DISABLE	0x0040	/* snarfed from linux */
140 #define IG4_CTL_RESTARTEN	0x0020	/* Allow Restart when master */
141 #define IG4_CTL_10BIT		0x0010	/* ctlr accepts 10-bit addresses */
142 #define IG4_CTL_SPEED_FAST	0x0004	/* snarfed from linux */
143 #define IG4_CTL_SPEED_STD	0x0002	/* snarfed from linux */
144 #define IG4_CTL_MASTER		0x0001	/* snarfed from linux */
145 
146 /*
147  * TAR_ADD - Target Address Register	22.2.2
148  *	     Default Value: 0x00000055F
149  *
150  *	10BIT		- RW controller starts its transfers in 10-bit
151  *			  address mode, else 7-bit.
152  *
153  *	SPECIAL		- RW Indicates whether software performs a General Call
154  *			  or START BYTE command.
155  *
156  *		0	  Ignore GC_OR_START and use TAR address.
157  *
158  *		1	  Perform special I2C Command based on GC_OR_START.
159  *
160  *	GC_OR_START	- RW (only if SPECIAL is set)
161  *
162  *		0	  General Call Address.  After issuing a General Call,
163  *			  only writes may be performed.  Attempting to issue
164  *			  a read command results in IX_ABRT in RAW_INTR_STAT.
165  *			  The controller remains in General Call mode until
166  *			  bit 11 (SPECIAL) is cleared.
167  *
168  *		1	  START BYTE.
169  *
170  *
171  * 	IC_TAR		- RW when transmitting a general call, these bits are
172  *			  ignored.  To generate a START BYTE, the address
173  *			  needs to be written into these bits once.
174  *
175  * This register should only be updated when the IIC is disabled (I2C_ENABLE=0)
176  */
177 #define IG4_TAR_10BIT		0x1000	/* start xfer in 10-bit mode */
178 #define IG4_TAR_SPECIAL		0x0800	/* Perform special command */
179 #define IG4_TAR_GC_OR_START	0x0400	/* General Call or Start */
180 #define IG4_TAR_ADDR_MASK	0x03FF	/* Target address */
181 
182 /*
183  * TAR_DATA_CMD - Data Buffer and Command Register	22.2.3
184  *
185  *	RESTART		- RW This bit controls whether a forced RESTART is
186  *			  issued before the byte is sent or received.
187  *
188  *		0	  If not set a RESTART is only issued if the tranfer
189  *			  direction is changing from the previous command.
190  *
191  *		1	  A RESTART is issued before the byte is sent or
192  *			  received, regardless of whether or not the transfer
193  *			  direction is changing from the previous command.
194  *
195  *	STOP		- RW This bit controls whether a STOP is issued after
196  *			  the byte is sent or received.
197  *
198  *		0	  STOP is not issued after this byte, regardless
199  *			  of whether or not the Tx FIFO is empty.
200  *
201  *		1	  STOP is issued after this byte, regardless of
202  *			  whether or not the Tx FIFO is empty.  If the
203  *			  Tx FIFO is not empty the master immediately tries
204  *			  to start a new transfer by issuing a START and
205  *			  arbitrating for the bus.
206  *
207  *			  i.e. the STOP is issued along with this byte,
208  *			  within the write stream.
209  *
210  *	COMMAND		- RW Control whether a read or write is performed.
211  *
212  *		0	  WRITE
213  *
214  *		1	  READ
215  *
216  *	DATA (7:0)	- RW Contains the data to be transmitted or received
217  *			  on the I2C bus.
218  *
219  *	NOTE: Writing to this register causes a START + slave + RW to be
220  *	      issued if the direction has changed or the last data byte was
221  *	      sent with a STOP.
222  *
223  *	NOTE: We control termination?  so this register must be written
224  *	      for each byte we wish to receive.  We can then drain the
225  *	      receive FIFO.
226  */
227 
228 #define IG4_DATA_RESTART	0x0400	/* Force RESTART */
229 #define IG4_DATA_STOP		0x0200	/* Force STOP[+START] */
230 #define IG4_DATA_COMMAND_RD	0x0100	/* bus direction 0=write 1=read */
231 #define IG4_DATA_MASK		0x00FF
232 
233 /*
234  * SS_SCL_HCNT - Standard Speed Clock High Count Register	22.2.4
235  * SS_SCL_LCNT - Standard Speed Clock Low Count Register	22.2.5
236  * FS_SCL_HCNT - Fast Speed Clock High Count Register		22.2.6
237  * FS_SCL_LCNT - Fast Speed Clock Low Count Register		22.2.7
238  *
239  *	COUNT (15:0)	- Set the period count to a value between 6 and
240  *			  65525.
241  */
242 #define IG4_SCL_CLOCK_MASK	0xFFFFU	/* count bits in register */
243 
244 /*
245  * INTR_STAT	- (RO) Interrupt Status Register		22.2.8
246  * INTR_MASK	- (RW) Interrupt Mask Register			22.2.9
247  * RAW_INTR_STAT- (RO) Raw Interrupt Status Register		22.2.10
248  *
249  *	GEN_CALL	Set only when a general call (broadcast) address
250  *			is received and acknowleged, stays set until
251  *			cleared by reading CLR_GEN_CALL.
252  *
253  *	START_DET	Set when a START or RESTART condition has occurred
254  *			on the interface.
255  *
256  *	STOP_DET	Set when a STOP condition has occurred on the
257  *			interface.
258  *
259  *	ACTIVITY	Set by any activity on the interface.  Cleared
260  *			by reading CLR_ACTIVITY or CLR_INTR.
261  *
262  *	TX_ABRT		Indicates the controller as a transmitter is
263  *			unable to complete the intended action.  When set,
264  *			the controller will hold the TX FIFO in a reset
265  *			state (flushed) until CLR_TX_ABORT is read to
266  *			clear the condition.  Once cleared, the TX FIFO
267  *			will be available again.
268  *
269  *	TX_EMPTY	Indicates that the transmitter is at or below
270  *			the specified TX_TL threshold.  Automatically
271  *			cleared by HW when the buffer level goes above
272  *			the threshold.
273  *
274  *	TX_OVER		Indicates that the processer attempted to write
275  *			to the TX FIFO while the TX FIFO was full.  Cleared
276  *			by reading CLR_TX_OVER.
277  *
278  *	RX_FULL		Indicates that the receive FIFO has reached or
279  *			exceeded the specified RX_TL threshold.  Cleared
280  *			by HW when the cpu drains the FIFO to below the
281  *			threshold.
282  *
283  *	RX_OVER		Indicates that the receive FIFO was unable to
284  *			accept new data and data was lost.  Cleared by
285  *			reading CLR_RX_OVER.
286  *
287  *	RX_UNDER	Indicates that the cpu attempted to read data
288  *			from the receive buffer while the RX FIFO was
289  *			empty.  Cleared by reading CLR_RX_UNDER.
290  *
291  * NOTES ON RAW_INTR_STAT:
292  *
293  *	This register can be used to monitor the GEN_CALL, START_DET,
294  *	STOP_DET, ACTIVITY, TX_ABRT, TX_EMPTY, TX_OVER, RX_FULL, RX_OVER,
295  *	and RX_UNDER bits.  The documentation is a bit unclear but presumably
296  *	this is the unlatched version.
297  *
298  *	Code should test FIFO conditions using the I2C_STA (status) register,
299  *	not the interrupt status registers.
300  */
301 
302 #define IG4_INTR_GEN_CALL	0x0800
303 #define IG4_INTR_START_DET	0x0400
304 #define IG4_INTR_STOP_DET	0x0200
305 #define IG4_INTR_ACTIVITY	0x0100
306 #define IG4_INTR_TX_ABRT	0x0040
307 #define IG4_INTR_TX_EMPTY	0x0010
308 #define IG4_INTR_TX_OVER	0x0008
309 #define IG4_INTR_RX_FULL	0x0004
310 #define IG4_INTR_RX_OVER	0x0002
311 #define IG4_INTR_RX_UNDER	0x0001
312 
313 /*
314  * RX_TL	- (RW) Receive FIFO Threshold Register		22.2.11
315  * TX_TL	- (RW) Transmit FIFO Threshold Register		22.2.12
316  *
317  * 	Specify the receive and transmit FIFO threshold register.  The
318  *	FIFOs have 16 elements.  The valid range is 0-15.  Setting a
319  *	value greater than 15 causes the actual value to be the maximum
320  *	depth of the FIFO.
321  *
322  *	Generally speaking since everything is messaged, we can use a
323  *	mid-level setting for both parameters and (e.g.) fully drain the
324  *	receive FIFO on the STOP_DET condition to handle loose ends.
325  */
326 #define IG4_FIFO_MASK		0x00FF
327 #define IG4_FIFO_LIMIT		16
328 
329 /*
330  * CLR_INTR	- (RO) Clear Interrupt Register			22.2.13
331  * CLR_RX_UNDER	- (RO) Clear Interrupt Register (specific)	22.2.14
332  * CLR_RX_OVER	- (RO) Clear Interrupt Register (specific)	22.2.15
333  * CLR_TX_OVER	- (RO) Clear Interrupt Register (specific)	22.2.16
334  * CLR_TX_ABORT	- (RO) Clear Interrupt Register (specific)	22.2.17
335  * CLR_ACTIVITY	- (RO) Clear Interrupt Register (specific)	22.2.18
336  * CLR_STOP_DET	- (RO) Clear Interrupt Register (specific)	22.2.19
337  * CLR_START_DET- (RO) Clear Interrupt Register (specific)	22.2.20
338  * CLR_GEN_CALL	- (RO) Clear Interrupt Register (specific)	22.2.21
339  *
340  *	CLR_* specific operations clear the appropriate bit in the
341  *	RAW_INTR_STAT register.  Intel does not really document whether
342  *	these operations clear the normal interrupt status register.
343  *
344  *	CLR_INTR clears bits in the normal interrupt status register and
345  *	presumably also the raw(?) register?  Intel is again unclear.
346  *
347  * NOTE: CLR_INTR only clears software-clearable interrupts.  Hardware
348  *	 clearable interrupts are controlled entirely by the hardware.
349  *	 CLR_INTR also clears the TX_ABRT_SOURCE register.
350  *
351  * NOTE: CLR_TX_ABORT also clears the TX_ABRT_SOURCE register and releases
352  *	 the TX FIFO from its flushed/reset state, allowing more writes
353  *	 to the TX FIFO.
354  *
355  * NOTE: CLR_ACTIVITY has no effect if the I2C bus is still active.
356  *	 Intel documents that the bit is automatically cleared when
357  *	 there is no further activity on the bus.
358  */
359 #define IG4_CLR_BIT		0x0001		/* Reflects source */
360 
361 /*
362  * I2C_EN	- (RW) I2C Enable Register			22.2.22
363  *
364  *	ABORT		Software can abort an I2C transfer by setting this
365  *			bit.  Hardware will clear the bit once the STOP has
366  *			been detected.  This bit can only be set while the
367  *			I2C interface is enabled.
368  *
369  *	I2C_ENABLE	Enable the controller, else disable it.
370  *			(Use I2C_ENABLE_STATUS to poll enable status
371  *			& wait for changes)
372  */
373 #define IG4_I2C_ABORT		0x0002
374 #define IG4_I2C_ENABLE		0x0001
375 
376 /*
377  * I2C_STA	- (RO) I2C Status Register			22.2.23
378  */
379 #define IG4_STATUS_ACTIVITY	0x0020	/* Controller is active */
380 #define IG4_STATUS_RX_FULL	0x0010	/* RX FIFO completely full */
381 #define IG4_STATUS_RX_NOTEMPTY	0x0008	/* RX FIFO not empty */
382 #define IG4_STATUS_TX_EMPTY	0x0004	/* TX FIFO completely empty */
383 #define IG4_STATUS_TX_NOTFULL	0x0002	/* TX FIFO not full */
384 #define IG4_STATUS_I2C_ACTIVE	0x0001	/* I2C bus is active */
385 
386 /*
387  * TXFLR	- (RO) Transmit FIFO Level Register		22.2.24
388  * RXFLR	- (RO) Receive FIFO Level Register		22.2.25
389  *
390  *	Read the number of entries currently in the Transmit or Receive
391  *	FIFOs.  Note that for some reason the mask is 9 bits instead of
392  *	the 8 bits the fill level controls.
393  */
394 #define IG4_FIFOLVL_MASK	0x001F
395 
396 /*
397  * SDA_HOLD	- (RW) SDA Hold Time Length Register		22.2.26
398  *
399  *	Set the SDA hold time length register in I2C clocks.
400  */
401 #define IG4_SDA_HOLD_MASK	0x00FF
402 
403 /*
404  * TX_ABRT_SOURCE- (RO) Transmit Abort Source Register		22.2.27
405  *
406  *	Indicates the cause of a transmit abort.  This can indicate a
407  *	software programming error or a device expected address width
408  *	mismatch or other issues.  The NORESTART conditions and GENCALL_NOACK
409  *	can only occur if a programming error was made in the driver software.
410  *
411  *	In particular, it should be possible to detect whether any devices
412  *	are on the bus by observing the GENCALL_READ status, and it might
413  *	be possible to detect ADDR7 vs ADDR10 mismatches.
414  */
415 #define IG4_ABRTSRC_TRANSFER		0x00010000 /* Abort initiated by user */
416 #define IG4_ABRTSRC_ARBLOST		0x00001000 /* Arbitration lost */
417 #define IG4_ABRTSRC_NORESTART_10	0x00000400 /* RESTART disabled */
418 #define IG4_ABRTSRC_NORESTART_START	0x00000200 /* RESTART disabled */
419 #define IG4_ABRTSRC_ACKED_START		0x00000080 /* Improper acked START */
420 #define IG4_ABRTSRC_GENCALL_NOACK	0x00000020 /* Improper GENCALL */
421 #define IG4_ABRTSRC_GENCALL_READ	0x00000010 /* Nobody acked GENCALL */
422 #define IG4_ABRTSRC_TXNOACK_DATA	0x00000008 /* data phase no ACK */
423 #define IG4_ABRTSRC_TXNOACK_ADDR10_2	0x00000004 /* addr10/1 phase no ACK */
424 #define IG4_ABRTSRC_TXNOACK_ADDR10_1	0x00000002 /* addr10/2 phase no ACK */
425 #define IG4_ABRTSRC_TXNOACK_ADDR7	0x00000001 /* addr7 phase no ACK */
426 
427 /*
428  * SLV_DATA_NACK - (RW) Generate Slave DATA NACK Register	22.2.28
429  *
430  *	When the controller is a receiver a NACK can be generated on
431  *	receipt of data.
432  *
433  *	NACK_GENERATE		Set to 0 for normal NACK/ACK generation.
434  *				Set to 1 to generate a NACK after next data
435  *				byte received.
436  *
437  */
438 #define IG4_NACK_GENERATE	0x0001
439 
440 /*
441  * DMA_CTRL	- (RW) DMA Control Register			22.2.29
442  *
443  *	Enables DMA on the transmit and/or receive DMA channel.
444  */
445 #define IG4_TX_DMA_ENABLE	0x0002
446 #define IG4_RX_DMA_ENABLE	0x0001
447 
448 /*
449  * DMA_TDLR	- (RW) DMA Transmit Data Level Register		22.2.30
450  * DMA_RDLR	- (RW) DMA Receive Data Level Register		22.2.31
451  *
452  *	Similar to RX_TL and TX_TL but controls when a DMA burst occurs
453  *	to empty or fill the FIFOs.  Use the same IG4_FIFO_MASK and
454  *	IG4_FIFO_LIMIT defines for RX_RL and TX_TL.
455  */
456 /* empty */
457 
458 /*
459  * SDA_SETUP	- (RW) SDA Setup Time Length Register		22.2.32
460  *
461  *	Set the SDA setup time length register in I2C clocks.
462  *	The register must be programmed with a value >=2.
463  *	(Defaults to 0x64).
464  */
465 #define IG4_SDA_SETUP_MASK	0x00FF
466 
467 /*
468  * ACK_GEN_CALL	- (RW) ACK General Call Register		22.2.33
469  *
470  *	Control whether the controller responds with a ACK or NACK when
471  *	it receives an I2C General Call address.
472  *
473  *	If set to 0 a NACK is generated and a General Call interrupt is
474  *	NOT generated.  Otherwise an ACK + interrupt is generated.
475  */
476 #define IG4_ACKGC_ACK		0x0001
477 
478 /*
479  * ENABLE_STATUS - (RO) Enable Status Registger			22.2.34
480  *
481  *	DATA_LOST	- Indicates that a slave receiver operation has
482  *			  been aborted with at least one data byte received
483  *			  from a transfer due to the I2C controller being
484  *			  disabled (IG4_I2C_ENABLE -> 0)
485  *
486  *	ENABLED		- Intel documentation is lacking but I assume this
487  *			  is a reflection of the IG4_I2C_ENABLE bit in the
488  *			  I2C_EN register.
489  *
490  */
491 #define IG4_ENASTAT_DATA_LOST	0x0004
492 #define IG4_ENASTAT_ENABLED	0x0001
493 
494 /*
495  * COMP_PARAM1 - (RO) Component Parameter Register		22.2.35
496  *		      Default Value 0x00FFFF6E
497  *
498  *	VALID		- Intel documentation is unclear but I believe this
499  *			  must be read as a 1 to indicate that the rest of
500  *			  the bits in the register are valid.
501  *
502  *	HASDMA		- Indicates that the chip is DMA-capable.  Presumably
503  *			  in certain virtualization cases the chip might be
504  *			  set to not be DMA-capable.
505  *
506  *	INTR_IO		- Indicates that all interrupts are combined to
507  *			  generate one interrupt.  If not set, interrupts
508  *			  are individual (more virtualization stuff?)
509  *
510  *	HCCNT_RO	- Indicates that the clock timing registers are
511  *			  RW.  If not set, the registers are RO.
512  *			  (more virtualization stuff).
513  *
514  *	MAXSPEED	- Indicates the maximum speed supported.
515  *
516  *	DATAW		- Indicates the internal bus width in bits.
517  */
518 #define IG4_PARAM1_TXFIFO_DEPTH(v)	(((v) >> 16) & 0xFF)
519 #define IG4_PARAM1_RXFIFO_DEPTH(v)	(((v) >> 8) & 0xFF)
520 #define IG4_PARAM1_CONFIG_VALID		0x00000080
521 #define IG4_PARAM1_CONFIG_HASDMA	0x00000040
522 #define IG4_PARAM1_CONFIG_INTR_IO	0x00000020
523 #define IG4_PARAM1_CONFIG_HCCNT_RO	0x00000010
524 #define IG4_PARAM1_CONFIG_MAXSPEED_MASK	0x0000000C
525 #define IG4_PARAM1_CONFIG_DATAW_MASK	0x00000003
526 
527 #define IG4_CONFIG_MAXSPEED_RESERVED00	0x00000000
528 #define IG4_CONFIG_MAXSPEED_STANDARD	0x00000004
529 #define IG4_CONFIG_MAXSPEED_FAST	0x00000008
530 #define IG4_CONFIG_MAXSPEED_HIGH	0x0000000C
531 
532 #define IG4_CONFIG_DATAW_8		0x00000000
533 #define IG4_CONFIG_DATAW_16		0x00000001
534 #define IG4_CONFIG_DATAW_32		0x00000002
535 #define IG4_CONFIG_DATAW_RESERVED11	0x00000003
536 
537 /*
538  * COMP_VER - (RO) Component Version Register			22.2.36
539  *		   Default Value 0x3131352A
540  *
541  *	Contains the chip version number.  All 32 bits.
542  */
543 #define IG4_COMP_VER		0x3131352A
544 
545 /*
546  * COMP_TYPE - (RO) (linux) Endian and bus width probe
547  *
548  * 	Read32 from this register and test against IG4_COMP_TYPE
549  *	to determine the bus width.  e.g. 01404457 = endian-reversed,
550  *	and 00000140 or 00004457 means internal 16-bit bus (?).
551  *
552  *	This register is not in the intel documentation, I pulled it
553  *	from the linux driver i2c-designware-core.c.
554  */
555 #define IG4_COMP_TYPE		0x44570140
556 
557 /*
558  * RESETS - (RW) Resets Register				22.2.37
559  *
560  *	Used to reset the I2C host controller by SW.  There is no timing
561  *	requirement, software can assert and de-assert in back-to-back
562  *	transactions.
563  *
564  *	00	I2C host controller is NOT in reset.
565  *	01	(reserved)
566  *	10	(reserved)
567  *	11	I2C host controller is in reset.
568  */
569 #define IG4_RESETS_ASSERT	0x0003
570 #define IG4_RESETS_DEASSERT	0x0000
571 
572 /*
573  * GENERAL - (RW) General Reigster				22.2.38
574  *
575  *	IOVOLT	0=1.8V 1=3.3V
576  *
577  *	LTR	0=Auto 1=SW
578  *
579  *	    In Auto mode the BIOS will write to the host controller's
580  *	    AUTO LTR Value register (offset 0x0814) with the active
581  *	    state LTR value, and will write to the SW LTR Value register
582  *	    (offset 0x0810) with the idle state LTR value.
583  *
584  *	    In SW mode the SW will write to the host controller SW LTR
585  *	    value (offset 0x0810).  It is the SW responsibility to update
586  *	    the LTR with the appropriate value.
587  */
588 #define IG4_GENERAL_IOVOLT3_3	0x0008
589 #define IG4_GENERAL_SWMODE	0x0004
590 
591 /*
592  * SW_LTR_VALUE - (RW) SW LTR Value Register			22.2.39
593  * AUTO_LTR_VALUE - (RW) SW LTR Value Register			22.2.40
594  *
595  *	Default value is 0x00000800 which means the best possible
596  *	service/response time.
597  *
598  *	It isn't quite clear how the snooping works.  There are two scale
599  *	bits for both sets but two of the four codes are reserved.  The
600  *	*SNOOP_VALUE() is specified as a 10-bit latency value.  If 0, it
601  *	indicates that the device cannot tolerate any delay and needs the
602  *	best possible service/response time.
603  *
604  *	I think this is for snooping (testing) the I2C bus.  The lowest
605  *	delay (0) probably runs the controller polling at a high, power hungry
606  *	rate.  But I dunno.
607  */
608 #define IG4_SWLTR_NSNOOP_REQ		0x80000000	/* (ro) */
609 #define IG4_SWLTR_NSNOOP_SCALE_MASK	0x1C000000	/* (ro) */
610 #define IG4_SWLTR_NSNOOP_SCALE_1US	0x08000000	/* (ro) */
611 #define IG4_SWLTR_NSNOOP_SCALE_32US	0x0C000000	/* (ro) */
612 #define IG4_SWLTR_NSNOOP_VALUE_DECODE(v) (((v) >> 16) & 0x3F)
613 #define IG4_SWLTR_NSNOOP_VALUE_ENCODE(v) (((v) & 0x3F) << 16)
614 
615 #define IG4_SWLTR_SNOOP_REQ		0x00008000	/* (rw) */
616 #define IG4_SWLTR_SNOOP_SCALE_MASK	0x00001C00	/* (rw) */
617 #define IG4_SWLTR_SNOOP_SCALE_1US	0x00000800	/* (rw) */
618 #define IG4_SWLTR_SNOOP_SCALE_32US	0x00000C00	/* (rw) */
619 #define IG4_SWLTR_SNOOP_VALUE_DECODE(v)	 ((v) & 0x3F)
620 #define IG4_SWLTR_SNOOP_VALUE_ENCODE(v)	 ((v) & 0x3F)
621 
622 #endif
623