xref: /freebsd/sys/dev/ichiic/ig4_reg.h (revision 13ea0450a9c8742119d36f3bf8f47accdce46e54)
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  * This controller is an I2C master only and cannot act as a slave.  The IO
51  * voltage should be set by the BIOS.  Standard (100Kb/s) and Fast (400Kb/s)
52  * and fast mode plus (1MB/s) is supported.  High speed mode (3.4 MB/s) is NOT
53  * supported.
54  */
55 
56 #ifndef _ICHIIC_IG4_REG_H_
57 #define _ICHIIC_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  */
77 
78 #define IG4_REG_CTL		0x0000	/* RW	Control Register */
79 #define IG4_REG_TAR_ADD		0x0004	/* RW	Target Address */
80 #define IG4_REG_HS_MADDR	0x000C	/* RW	High Speed Master Mode Code 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_RD_REQ	0x0050	/* RO	Clear RD_Req Interrupt */
96 #define IG4_REG_CLR_TX_ABORT	0x0054	/* RO	Clear TX_Abort Interrupt */
97 #define IG4_REG_CLR_RX_DONE	0x0058	/* RO	Clear RX_Done Interrupt */
98 #define IG4_REG_CLR_ACTIVITY	0x005C	/* RO	Clear Activity Interrupt */
99 #define IG4_REG_CLR_STOP_DET	0x0060	/* RO	Clear STOP Detection Int */
100 #define IG4_REG_CLR_START_DET	0x0064	/* RO	Clear START Detection Int */
101 #define IG4_REG_CLR_GEN_CALL	0x0068	/* RO	Clear General Call Interrupt */
102 #define IG4_REG_I2C_EN		0x006C	/* RW	I2C Enable */
103 #define IG4_REG_I2C_STA		0x0070	/* RO	I2C Status */
104 #define IG4_REG_TXFLR		0x0074	/* RO	Transmit FIFO Level */
105 #define IG4_REG_RXFLR		0x0078	/* RO	Receive FIFO Level */
106 #define IG4_REG_SDA_HOLD	0x007C	/* RW	SDA Hold Time Length */
107 #define IG4_REG_TX_ABRT_SOURCE	0x0080	/* RO	Transmit Abort Source */
108 #define IG4_REG_SLV_DATA_NACK	0x0084	/* RW	General Slave Data NACK */
109 #define IG4_REG_DMA_CTRL	0x0088	/* RW	DMA Control */
110 #define IG4_REG_DMA_TDLR	0x008C	/* RW	DMA Transmit Data Level */
111 #define IG4_REG_DMA_RDLR	0x0090	/* RW	DMA Receive Data Level */
112 #define IG4_REG_SDA_SETUP	0x0094	/* RW	SDA Setup */
113 #define IG4_REG_ACK_GENERAL_CALL 0x0098	/* RW	I2C ACK General Call */
114 #define IG4_REG_ENABLE_STATUS	0x009C	/* RO	Enable Status */
115 /* Available at least on Atom SoCs and Haswell mobile. */
116 #define IG4_REG_COMP_PARAM1	0x00F4	/* RO	Component Parameter */
117 #define IG4_REG_COMP_VER	0x00F8	/* RO	Component Version */
118 /* Available at least on Atom SoCs */
119 #define IG4_REG_COMP_TYPE	0x00FC	/* RO	Probe width/endian? (linux) */
120 /* Available on Skylake-U/Y and Kaby Lake-U/Y */
121 #define IG4_REG_RESETS_SKL	0x0204	/* RW	Reset Register */
122 #define IG4_REG_ACTIVE_LTR_VALUE 0x0210	/* RW	Active LTR Value */
123 #define IG4_REG_IDLE_LTR_VALUE	0x0214	/* RW	Idle LTR Value */
124 #define IG4_REG_TX_ACK_COUNT	0x0218	/* RO	TX ACK Count */
125 #define IG4_REG_RX_BYTE_COUNT	0x021C	/* RO	RX ACK Count */
126 #define IG4_REG_DEVIDLE_CTRL	0x024C	/* RW	Device Control */
127 /* Available at least on Atom SoCs */
128 #define IG4_REG_CLK_PARMS	0x0800	/* RW	Clock Parameters */
129 /* Available at least on Atom SoCs and Haswell mobile */
130 #define IG4_REG_RESETS_HSW	0x0804	/* RW	Reset Register */
131 #define IG4_REG_GENERAL		0x0808	/* RW	General Register */
132 /* These LTR config registers are at least available on Haswell mobile. */
133 #define IG4_REG_SW_LTR_VALUE	0x0810	/* RW	SW LTR Value */
134 #define IG4_REG_AUTO_LTR_VALUE	0x0814	/* RW	Auto LTR Value */
135 
136 /*
137  * CTL - Control Register 		22.2.1
138  *	 Default Value: 0x0000007F.
139  *
140  *	RESTARTEN	- RW Restart Enable
141  *	10BIT		- RW Controller operates in 10-bit mode, else 7-bit
142  *
143  * NOTE: When restart is disabled the controller is incapable of
144  *	 performing the following functions:
145  *
146  *		 Sending a START Byte
147  *		 Performing any high-speed mode op
148  *		 Performing direction changes in combined format mode
149  *		 Performing a read operation with a 10-bit address
150  *
151  *	 Attempting to perform the above operations will result in the
152  *	 TX_ABORT bit being set in RAW_INTR_STAT.
153  */
154 #define IG4_CTL_SLAVE_DISABLE	0x0040	/* snarfed from linux */
155 #define IG4_CTL_RESTARTEN	0x0020	/* Allow Restart when master */
156 #define IG4_CTL_10BIT		0x0010	/* ctlr accepts 10-bit addresses */
157 #define IG4_CTL_SPEED_FAST	0x0004	/* snarfed from linux */
158 #define IG4_CTL_SPEED_STD	0x0002	/* snarfed from linux */
159 #define IG4_CTL_MASTER		0x0001	/* snarfed from linux */
160 
161 /*
162  * TAR_ADD - Target Address Register	22.2.2
163  *	     Default Value: 0x00000055F
164  *
165  *	10BIT		- RW controller starts its transfers in 10-bit
166  *			  address mode, else 7-bit.
167  *
168  *	SPECIAL		- RW Indicates whether software performs a General Call
169  *			  or START BYTE command.
170  *
171  *		0	  Ignore GC_OR_START and use TAR address.
172  *
173  *		1	  Perform special I2C Command based on GC_OR_START.
174  *
175  *	GC_OR_START	- RW (only if SPECIAL is set)
176  *
177  *		0	  General Call Address.  After issuing a General Call,
178  *			  only writes may be performed.  Attempting to issue
179  *			  a read command results in IX_ABRT in RAW_INTR_STAT.
180  *			  The controller remains in General Call mode until
181  *			  bit 11 (SPECIAL) is cleared.
182  *
183  *		1	  START BYTE.
184  *
185  *
186  * 	IC_TAR		- RW when transmitting a general call, these bits are
187  *			  ignored.  To generate a START BYTE, the address
188  *			  needs to be written into these bits once.
189  *
190  * This register should only be updated when the IIC is disabled (I2C_ENABLE=0)
191  */
192 #define IG4_TAR_10BIT		0x1000	/* start xfer in 10-bit mode */
193 #define IG4_TAR_SPECIAL		0x0800	/* Perform special command */
194 #define IG4_TAR_GC_OR_START	0x0400	/* General Call or Start */
195 #define IG4_TAR_ADDR_MASK	0x03FF	/* Target address */
196 
197 /*
198  * TAR_DATA_CMD - Data Buffer and Command Register	22.2.3
199  *
200  *	RESTART		- RW This bit controls whether a forced RESTART is
201  *			  issued before the byte is sent or received.
202  *
203  *		0	  If not set a RESTART is only issued if the transfer
204  *			  direction is changing from the previous command.
205  *
206  *		1	  A RESTART is issued before the byte is sent or
207  *			  received, regardless of whether or not the transfer
208  *			  direction is changing from the previous command.
209  *
210  *	STOP		- RW This bit controls whether a STOP is issued after
211  *			  the byte is sent or received.
212  *
213  *		0	  STOP is not issued after this byte, regardless
214  *			  of whether or not the Tx FIFO is empty.
215  *
216  *		1	  STOP is issued after this byte, regardless of
217  *			  whether or not the Tx FIFO is empty.  If the
218  *			  Tx FIFO is not empty the master immediately tries
219  *			  to start a new transfer by issuing a START and
220  *			  arbitrating for the bus.
221  *
222  *			  i.e. the STOP is issued along with this byte,
223  *			  within the write stream.
224  *
225  *	COMMAND		- RW Control whether a read or write is performed.
226  *
227  *		0	  WRITE
228  *
229  *		1	  READ
230  *
231  *	DATA (7:0)	- RW Contains the data to be transmitted or received
232  *			  on the I2C bus.
233  *
234  *	NOTE: Writing to this register causes a START + slave + RW to be
235  *	      issued if the direction has changed or the last data byte was
236  *	      sent with a STOP.
237  *
238  *	NOTE: We control termination?  so this register must be written
239  *	      for each byte we wish to receive.  We can then drain the
240  *	      receive FIFO.
241  */
242 
243 #define IG4_DATA_RESTART	0x0400	/* Force RESTART */
244 #define IG4_DATA_STOP		0x0200	/* Force STOP[+START] */
245 #define IG4_DATA_COMMAND_RD	0x0100	/* bus direction 0=write 1=read */
246 #define IG4_DATA_MASK		0x00FF
247 
248 /*
249  * SS_SCL_HCNT - Standard Speed Clock High Count Register	22.2.4
250  * SS_SCL_LCNT - Standard Speed Clock Low Count Register	22.2.5
251  * FS_SCL_HCNT - Fast Speed Clock High Count Register		22.2.6
252  * FS_SCL_LCNT - Fast Speed Clock Low Count Register		22.2.7
253  *
254  *	COUNT (15:0)	- Set the period count to a value between 6 and
255  *			  65525.
256  */
257 #define IG4_SCL_CLOCK_MASK	0xFFFFU	/* count bits in register */
258 
259 /*
260  * INTR_STAT	- (RO) Interrupt Status Register		22.2.8
261  * INTR_MASK	- (RW) Interrupt Mask Register			22.2.9
262  * RAW_INTR_STAT- (RO) Raw Interrupt Status Register		22.2.10
263  *
264  *	GEN_CALL	Set only when a general call (broadcast) address
265  *			is received and acknowleged, stays set until
266  *			cleared by reading CLR_GEN_CALL.
267  *
268  *	START_DET	Set when a START or RESTART condition has occurred
269  *			on the interface.
270  *
271  *	STOP_DET	Set when a STOP condition has occurred on the
272  *			interface.
273  *
274  *	ACTIVITY	Set by any activity on the interface.  Cleared
275  *			by reading CLR_ACTIVITY or CLR_INTR.
276  *
277  *	TX_ABRT		Indicates the controller as a transmitter is
278  *			unable to complete the intended action.  When set,
279  *			the controller will hold the TX FIFO in a reset
280  *			state (flushed) until CLR_TX_ABORT is read to
281  *			clear the condition.  Once cleared, the TX FIFO
282  *			will be available again.
283  *
284  *	TX_EMPTY	Indicates that the transmitter is at or below
285  *			the specified TX_TL threshold.  Automatically
286  *			cleared by HW when the buffer level goes above
287  *			the threshold.
288  *
289  *	TX_OVER		Indicates that the processor attempted to write
290  *			to the TX FIFO while the TX FIFO was full.  Cleared
291  *			by reading CLR_TX_OVER.
292  *
293  *	RX_FULL		Indicates that the receive FIFO has reached or
294  *			exceeded the specified RX_TL threshold.  Cleared
295  *			by HW when the cpu drains the FIFO to below the
296  *			threshold.
297  *
298  *	RX_OVER		Indicates that the receive FIFO was unable to
299  *			accept new data and data was lost.  Cleared by
300  *			reading CLR_RX_OVER.
301  *
302  *	RX_UNDER	Indicates that the cpu attempted to read data
303  *			from the receive buffer while the RX FIFO was
304  *			empty.  Cleared by reading CLR_RX_UNDER.
305  *
306  * NOTES ON RAW_INTR_STAT:
307  *
308  *	This register can be used to monitor the GEN_CALL, START_DET,
309  *	STOP_DET, ACTIVITY, TX_ABRT, TX_EMPTY, TX_OVER, RX_FULL, RX_OVER,
310  *	and RX_UNDER bits.  The documentation is a bit unclear but presumably
311  *	this is the unlatched version.
312  *
313  *	Code should test FIFO conditions using the I2C_STA (status) register,
314  *	not the interrupt status registers.
315  */
316 
317 #define IG4_INTR_GEN_CALL	0x0800
318 #define IG4_INTR_START_DET	0x0400
319 #define IG4_INTR_STOP_DET	0x0200
320 #define IG4_INTR_ACTIVITY	0x0100
321 #define IG4_INTR_TX_ABRT	0x0040
322 #define IG4_INTR_TX_EMPTY	0x0010
323 #define IG4_INTR_TX_OVER	0x0008
324 #define IG4_INTR_RX_FULL	0x0004
325 #define IG4_INTR_RX_OVER	0x0002
326 #define IG4_INTR_RX_UNDER	0x0001
327 
328 /*
329  * RX_TL	- (RW) Receive FIFO Threshold Register		22.2.11
330  * TX_TL	- (RW) Transmit FIFO Threshold Register		22.2.12
331  *
332  * 	Specify the receive and transmit FIFO threshold register.  The
333  *	FIFOs have 16 elements.  The valid range is 0-15.  Setting a
334  *	value greater than 15 causes the actual value to be the maximum
335  *	depth of the FIFO.
336  *
337  *	Generally speaking since everything is messaged, we can use a
338  *	mid-level setting for both parameters and (e.g.) fully drain the
339  *	receive FIFO on the STOP_DET condition to handle loose ends.
340  */
341 #define IG4_FIFO_MASK		0x00FF
342 #define IG4_FIFO_LIMIT		16
343 
344 /*
345  * CLR_INTR	- (RO) Clear Interrupt Register			22.2.13
346  * CLR_RX_UNDER	- (RO) Clear Interrupt Register (specific)	22.2.14
347  * CLR_RX_OVER	- (RO) Clear Interrupt Register (specific)	22.2.15
348  * CLR_TX_OVER	- (RO) Clear Interrupt Register (specific)	22.2.16
349  * CLR_TX_ABORT	- (RO) Clear Interrupt Register (specific)	22.2.17
350  * CLR_ACTIVITY	- (RO) Clear Interrupt Register (specific)	22.2.18
351  * CLR_STOP_DET	- (RO) Clear Interrupt Register (specific)	22.2.19
352  * CLR_START_DET- (RO) Clear Interrupt Register (specific)	22.2.20
353  * CLR_GEN_CALL	- (RO) Clear Interrupt Register (specific)	22.2.21
354  *
355  *	CLR_* specific operations clear the appropriate bit in the
356  *	RAW_INTR_STAT register.  Intel does not really document whether
357  *	these operations clear the normal interrupt status register.
358  *
359  *	CLR_INTR clears bits in the normal interrupt status register and
360  *	presumably also the raw(?) register?  Intel is again unclear.
361  *
362  * NOTE: CLR_INTR only clears software-clearable interrupts.  Hardware
363  *	 clearable interrupts are controlled entirely by the hardware.
364  *	 CLR_INTR also clears the TX_ABRT_SOURCE register.
365  *
366  * NOTE: CLR_TX_ABORT also clears the TX_ABRT_SOURCE register and releases
367  *	 the TX FIFO from its flushed/reset state, allowing more writes
368  *	 to the TX FIFO.
369  *
370  * NOTE: CLR_ACTIVITY has no effect if the I2C bus is still active.
371  *	 Intel documents that the bit is automatically cleared when
372  *	 there is no further activity on the bus.
373  */
374 #define IG4_CLR_BIT		0x0001		/* Reflects source */
375 
376 /*
377  * I2C_EN	- (RW) I2C Enable Register			22.2.22
378  *
379  *	ABORT		Software can abort an I2C transfer by setting this
380  *			bit.  Hardware will clear the bit once the STOP has
381  *			been detected.  This bit can only be set while the
382  *			I2C interface is enabled.
383  *
384  *	I2C_ENABLE	Enable the controller, else disable it.
385  *			(Use I2C_ENABLE_STATUS to poll enable status
386  *			& wait for changes)
387  */
388 #define IG4_I2C_ABORT		0x0002
389 #define IG4_I2C_ENABLE		0x0001
390 
391 /*
392  * I2C_STA	- (RO) I2C Status Register			22.2.23
393  */
394 #define IG4_STATUS_ACTIVITY	0x0020	/* Controller is active */
395 #define IG4_STATUS_RX_FULL	0x0010	/* RX FIFO completely full */
396 #define IG4_STATUS_RX_NOTEMPTY	0x0008	/* RX FIFO not empty */
397 #define IG4_STATUS_TX_EMPTY	0x0004	/* TX FIFO completely empty */
398 #define IG4_STATUS_TX_NOTFULL	0x0002	/* TX FIFO not full */
399 #define IG4_STATUS_I2C_ACTIVE	0x0001	/* I2C bus is active */
400 
401 /*
402  * TXFLR	- (RO) Transmit FIFO Level Register		22.2.24
403  * RXFLR	- (RO) Receive FIFO Level Register		22.2.25
404  *
405  *	Read the number of entries currently in the Transmit or Receive
406  *	FIFOs.  Note that for some reason the mask is 9 bits instead of
407  *	the 8 bits the fill level controls.
408  */
409 #define IG4_FIFOLVL_MASK	0x001F
410 
411 /*
412  * SDA_HOLD	- (RW) SDA Hold Time Length Register		22.2.26
413  *
414  *	Set the SDA hold time length register in I2C clocks.
415  */
416 #define IG4_SDA_HOLD_MASK	0x00FF
417 
418 /*
419  * TX_ABRT_SOURCE- (RO) Transmit Abort Source Register		22.2.27
420  *
421  *	Indicates the cause of a transmit abort.  This can indicate a
422  *	software programming error or a device expected address width
423  *	mismatch or other issues.  The NORESTART conditions and GENCALL_NOACK
424  *	can only occur if a programming error was made in the driver software.
425  *
426  *	In particular, it should be possible to detect whether any devices
427  *	are on the bus by observing the GENCALL_READ status, and it might
428  *	be possible to detect ADDR7 vs ADDR10 mismatches.
429  */
430 #define IG4_ABRTSRC_TRANSFER		0x00010000 /* Abort initiated by user */
431 #define IG4_ABRTSRC_ARBLOST		0x00001000 /* Arbitration lost */
432 #define IG4_ABRTSRC_NORESTART_10	0x00000400 /* RESTART disabled */
433 #define IG4_ABRTSRC_NORESTART_START	0x00000200 /* RESTART disabled */
434 #define IG4_ABRTSRC_ACKED_START		0x00000080 /* Improper acked START */
435 #define IG4_ABRTSRC_GENCALL_NOACK	0x00000020 /* Improper GENCALL */
436 #define IG4_ABRTSRC_GENCALL_READ	0x00000010 /* Nobody acked GENCALL */
437 #define IG4_ABRTSRC_TXNOACK_DATA	0x00000008 /* data phase no ACK */
438 #define IG4_ABRTSRC_TXNOACK_ADDR10_2	0x00000004 /* addr10/1 phase no ACK */
439 #define IG4_ABRTSRC_TXNOACK_ADDR10_1	0x00000002 /* addr10/2 phase no ACK */
440 #define IG4_ABRTSRC_TXNOACK_ADDR7	0x00000001 /* addr7 phase no ACK */
441 
442 /*
443  * SLV_DATA_NACK - (RW) Generate Slave DATA NACK Register	22.2.28
444  *
445  *	When the controller is a receiver a NACK can be generated on
446  *	receipt of data.
447  *
448  *	NACK_GENERATE		Set to 0 for normal NACK/ACK generation.
449  *				Set to 1 to generate a NACK after next data
450  *				byte received.
451  *
452  */
453 #define IG4_NACK_GENERATE	0x0001
454 
455 /*
456  * DMA_CTRL	- (RW) DMA Control Register			22.2.29
457  *
458  *	Enables DMA on the transmit and/or receive DMA channel.
459  */
460 #define IG4_TX_DMA_ENABLE	0x0002
461 #define IG4_RX_DMA_ENABLE	0x0001
462 
463 /*
464  * DMA_TDLR	- (RW) DMA Transmit Data Level Register		22.2.30
465  * DMA_RDLR	- (RW) DMA Receive Data Level Register		22.2.31
466  *
467  *	Similar to RX_TL and TX_TL but controls when a DMA burst occurs
468  *	to empty or fill the FIFOs.  Use the same IG4_FIFO_MASK and
469  *	IG4_FIFO_LIMIT defines for RX_RL and TX_TL.
470  */
471 /* empty */
472 
473 /*
474  * SDA_SETUP	- (RW) SDA Setup Time Length Register		22.2.32
475  *
476  *	Set the SDA setup time length register in I2C clocks.
477  *	The register must be programmed with a value >=2.
478  *	(Defaults to 0x64).
479  */
480 #define IG4_SDA_SETUP_MASK	0x00FF
481 
482 /*
483  * ACK_GEN_CALL	- (RW) ACK General Call Register		22.2.33
484  *
485  *	Control whether the controller responds with a ACK or NACK when
486  *	it receives an I2C General Call address.
487  *
488  *	If set to 0 a NACK is generated and a General Call interrupt is
489  *	NOT generated.  Otherwise an ACK + interrupt is generated.
490  */
491 #define IG4_ACKGC_ACK		0x0001
492 
493 /*
494  * ENABLE_STATUS - (RO) Enable Status Registger			22.2.34
495  *
496  *	DATA_LOST	- Indicates that a slave receiver operation has
497  *			  been aborted with at least one data byte received
498  *			  from a transfer due to the I2C controller being
499  *			  disabled (IG4_I2C_ENABLE -> 0)
500  *
501  *	ENABLED		- Intel documentation is lacking but I assume this
502  *			  is a reflection of the IG4_I2C_ENABLE bit in the
503  *			  I2C_EN register.
504  *
505  */
506 #define IG4_ENASTAT_DATA_LOST	0x0004
507 #define IG4_ENASTAT_ENABLED	0x0001
508 
509 /*
510  * COMP_PARAM1 - (RO) Component Parameter Register		22.2.35
511  *		      Default Value 0x00FFFF6E
512  *
513  *	VALID		- Intel documentation is unclear but I believe this
514  *			  must be read as a 1 to indicate that the rest of
515  *			  the bits in the register are valid.
516  *
517  *	HASDMA		- Indicates that the chip is DMA-capable.  Presumably
518  *			  in certain virtualization cases the chip might be
519  *			  set to not be DMA-capable.
520  *
521  *	INTR_IO		- Indicates that all interrupts are combined to
522  *			  generate one interrupt.  If not set, interrupts
523  *			  are individual (more virtualization stuff?)
524  *
525  *	HCCNT_RO	- Indicates that the clock timing registers are
526  *			  RW.  If not set, the registers are RO.
527  *			  (more virtualization stuff).
528  *
529  *	MAXSPEED	- Indicates the maximum speed supported.
530  *
531  *	DATAW		- Indicates the internal bus width in bits.
532  */
533 #define IG4_PARAM1_TXFIFO_DEPTH(v)	(((v) >> 16) & 0xFF)
534 #define IG4_PARAM1_RXFIFO_DEPTH(v)	(((v) >> 8) & 0xFF)
535 #define IG4_PARAM1_CONFIG_VALID		0x00000080
536 #define IG4_PARAM1_CONFIG_HASDMA	0x00000040
537 #define IG4_PARAM1_CONFIG_INTR_IO	0x00000020
538 #define IG4_PARAM1_CONFIG_HCCNT_RO	0x00000010
539 #define IG4_PARAM1_CONFIG_MAXSPEED_MASK	0x0000000C
540 #define IG4_PARAM1_CONFIG_DATAW_MASK	0x00000003
541 
542 #define IG4_CONFIG_MAXSPEED_RESERVED00	0x00000000
543 #define IG4_CONFIG_MAXSPEED_STANDARD	0x00000004
544 #define IG4_CONFIG_MAXSPEED_FAST	0x00000008
545 #define IG4_CONFIG_MAXSPEED_HIGH	0x0000000C
546 
547 #define IG4_CONFIG_DATAW_8		0x00000000
548 #define IG4_CONFIG_DATAW_16		0x00000001
549 #define IG4_CONFIG_DATAW_32		0x00000002
550 #define IG4_CONFIG_DATAW_RESERVED11	0x00000003
551 
552 /*
553  * COMP_VER - (RO) Component Version Register			22.2.36
554  *
555  *	Contains the chip version number.  All 32 bits.
556  */
557 #define IG4_COMP_MIN_VER		0x3131352A
558 
559 /*
560  * COMP_TYPE - (RO) (linux) Endian and bus width probe
561  *
562  * 	Read32 from this register and test against IG4_COMP_TYPE
563  *	to determine the bus width.  e.g. 01404457 = endian-reversed,
564  *	and 00000140 or 00004457 means internal 16-bit bus (?).
565  *
566  *	This register is not in the intel documentation, I pulled it
567  *	from the linux driver i2c-designware-core.c.
568  */
569 #define IG4_COMP_TYPE		0x44570140
570 
571 /*
572  * RESETS - (RW) Resets Register				22.2.37
573  *
574  *	Used to reset the I2C host controller by SW.  There is no timing
575  *	requirement, software can assert and de-assert in back-to-back
576  *	transactions.
577  *
578  *	00	I2C host controller is NOT in reset.
579  *	01	(reserved)
580  *	10	(reserved)
581  *	11	I2C host controller is in reset.
582  */
583 #define IG4_RESETS_ASSERT_HSW	0x0003
584 #define IG4_RESETS_DEASSERT_HSW	0x0000
585 
586 /* Skylake-U/Y and Kaby Lake-U/Y have the reset bits inverted */
587 #define IG4_RESETS_DEASSERT_SKL	0x0003
588 #define IG4_RESETS_ASSERT_SKL	0x0000
589 
590 /* Newer versions of the I2C controller allow to check whether
591  * the above ASSERT/DEASSERT is necessary by querying the DEVIDLE_CONTROL
592  * register.
593  *
594  * the RESTORE_REQUIRED bit can be cleared by writing 1
595  * the DEVICE_IDLE status can be set to put the controller in an idle state
596  *
597  */
598 #define IG4_RESTORE_REQUIRED	0x0008
599 #define IG4_DEVICE_IDLE		0x0004
600 
601 /*
602  * GENERAL - (RW) General Reigster				22.2.38
603  *
604  *	IOVOLT	0=1.8V 1=3.3V
605  *
606  *	LTR	0=Auto 1=SW
607  *
608  *	    In Auto mode the BIOS will write to the host controller's
609  *	    AUTO LTR Value register (offset 0x0814) with the active
610  *	    state LTR value, and will write to the SW LTR Value register
611  *	    (offset 0x0810) with the idle state LTR value.
612  *
613  *	    In SW mode the SW will write to the host controller SW LTR
614  *	    value (offset 0x0810).  It is the SW responsibility to update
615  *	    the LTR with the appropriate value.
616  */
617 #define IG4_GENERAL_IOVOLT3_3	0x0008
618 #define IG4_GENERAL_SWMODE	0x0004
619 
620 /*
621  * SW_LTR_VALUE - (RW) SW LTR Value Register			22.2.39
622  * AUTO_LTR_VALUE - (RW) SW LTR Value Register			22.2.40
623  *
624  *	Default value is 0x00000800 which means the best possible
625  *	service/response time.
626  *
627  *	It isn't quite clear how the snooping works.  There are two scale
628  *	bits for both sets but two of the four codes are reserved.  The
629  *	*SNOOP_VALUE() is specified as a 10-bit latency value.  If 0, it
630  *	indicates that the device cannot tolerate any delay and needs the
631  *	best possible service/response time.
632  *
633  *	I think this is for snooping (testing) the I2C bus.  The lowest
634  *	delay (0) probably runs the controller polling at a high, power hungry
635  *	rate.  But I dunno.
636  */
637 #define IG4_SWLTR_NSNOOP_REQ		0x80000000	/* (ro) */
638 #define IG4_SWLTR_NSNOOP_SCALE_MASK	0x1C000000	/* (ro) */
639 #define IG4_SWLTR_NSNOOP_SCALE_1US	0x08000000	/* (ro) */
640 #define IG4_SWLTR_NSNOOP_SCALE_32US	0x0C000000	/* (ro) */
641 #define IG4_SWLTR_NSNOOP_VALUE_DECODE(v) (((v) >> 16) & 0x3F)
642 #define IG4_SWLTR_NSNOOP_VALUE_ENCODE(v) (((v) & 0x3F) << 16)
643 
644 #define IG4_SWLTR_SNOOP_REQ		0x00008000	/* (rw) */
645 #define IG4_SWLTR_SNOOP_SCALE_MASK	0x00001C00	/* (rw) */
646 #define IG4_SWLTR_SNOOP_SCALE_1US	0x00000800	/* (rw) */
647 #define IG4_SWLTR_SNOOP_SCALE_32US	0x00000C00	/* (rw) */
648 #define IG4_SWLTR_SNOOP_VALUE_DECODE(v)	 ((v) & 0x3F)
649 #define IG4_SWLTR_SNOOP_VALUE_ENCODE(v)	 ((v) & 0x3F)
650 
651 #endif /* _ICHIIC_IG4_REG_H_ */
652