[go: nahoru, domu]

1
2/*********************************************************************
3 *
4 *	vlsi_ir.h:	VLSI82C147 PCI IrDA controller driver for Linux
5 *
6 *	Version:	0.5
7 *
8 *	Copyright (c) 2001-2003 Martin Diehl
9 *
10 *	This program is free software; you can redistribute it and/or
11 *	modify it under the terms of the GNU General Public License as
12 *	published by the Free Software Foundation; either version 2 of
13 *	the License, or (at your option) any later version.
14 *
15 *	This program is distributed in the hope that it will be useful,
16 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
17 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 *	GNU General Public License for more details.
19 *
20 *	You should have received a copy of the GNU General Public License
21 *	along with this program; if not, see <http://www.gnu.org/licenses/>.
22 *
23 ********************************************************************/
24
25#ifndef IRDA_VLSI_FIR_H
26#define IRDA_VLSI_FIR_H
27
28/* ================================================================
29 * compatibility stuff
30 */
31
32/* definitions not present in pci_ids.h */
33
34#ifndef PCI_CLASS_WIRELESS_IRDA
35#define PCI_CLASS_WIRELESS_IRDA		0x0d00
36#endif
37
38#ifndef PCI_CLASS_SUBCLASS_MASK
39#define PCI_CLASS_SUBCLASS_MASK		0xffff
40#endif
41
42/* ================================================================ */
43
44/* non-standard PCI registers */
45
46enum vlsi_pci_regs {
47	VLSI_PCI_CLKCTL		= 0x40,		/* chip clock input control */
48	VLSI_PCI_MSTRPAGE	= 0x41,		/* addr [31:24] for all busmaster cycles */
49	VLSI_PCI_IRMISC		= 0x42		/* mainly legacy UART related */
50};
51
52/* ------------------------------------------ */
53
54/* VLSI_PCI_CLKCTL: Clock Control Register (u8, rw) */
55
56/* Three possible clock sources: either on-chip 48MHz PLL or
57 * external clock applied to EXTCLK pin. External clock may
58 * be either 48MHz or 40MHz, which is indicated by XCKSEL.
59 * CLKSTP controls whether the selected clock source gets
60 * connected to the IrDA block.
61 *
62 * On my HP OB-800 the BIOS sets external 40MHz clock as source
63 * when IrDA enabled and I've never detected any PLL lock success.
64 * Apparently the 14.3...MHz OSC input required for the PLL to work
65 * is not connected and the 40MHz EXTCLK is provided externally.
66 * At least this is what makes the driver working for me.
67 */
68
69enum vlsi_pci_clkctl {
70
71	/* PLL control */
72
73	CLKCTL_PD_INV		= 0x04,		/* PD#: inverted power down signal,
74						 * i.e. PLL is powered, if PD_INV set */
75	CLKCTL_LOCK		= 0x40,		/* (ro) set, if PLL is locked */
76
77	/* clock source selection */
78
79	CLKCTL_EXTCLK		= 0x20,		/* set to select external clock input, not PLL */
80	CLKCTL_XCKSEL		= 0x10,		/* set to indicate EXTCLK is 40MHz, not 48MHz */
81
82	/* IrDA block control */
83
84	CLKCTL_CLKSTP		= 0x80,		/* set to disconnect from selected clock source */
85	CLKCTL_WAKE		= 0x08		/* set to enable wakeup feature: whenever IR activity
86						 * is detected, PD_INV gets set(?) and CLKSTP cleared */
87};
88
89/* ------------------------------------------ */
90
91/* VLSI_PCI_MSTRPAGE: Master Page Register (u8, rw) and busmastering stuff */
92
93#define DMA_MASK_USED_BY_HW	0xffffffff
94#define DMA_MASK_MSTRPAGE	0x00ffffff
95#define MSTRPAGE_VALUE		(DMA_MASK_MSTRPAGE >> 24)
96
97	/* PCI busmastering is somewhat special for this guy - in short:
98	 *
99	 * We select to operate using fixed MSTRPAGE=0, use ISA DMA
100	 * address restrictions to make the PCI BM api aware of this,
101	 * but ensure the hardware is dealing with real 32bit access.
102	 *
103	 * In detail:
104	 * The chip executes normal 32bit busmaster cycles, i.e.
105	 * drives all 32 address lines. These addresses however are
106	 * composed of [0:23] taken from various busaddr-pointers
107	 * and [24:31] taken from the MSTRPAGE register in the VLSI82C147
108	 * config space. Therefore _all_ busmastering must be
109	 * targeted to/from one single 16MB (busaddr-) superpage!
110	 * The point is to make sure all the allocations for memory
111	 * locations with busmaster access (ring descriptors, buffers)
112	 * are indeed bus-mappable to the same 16MB range (for x86 this
113	 * means they must reside in the same 16MB physical memory address
114	 * range). The only constraint we have which supports "several objects
115	 * mappable to common 16MB range" paradigma, is the old ISA DMA
116	 * restriction to the first 16MB of physical address range.
117	 * Hence the approach here is to enable PCI busmaster support using
118	 * the correct 32bit dma-mask used by the chip. Afterwards the device's
119	 * dma-mask gets restricted to 24bit, which must be honoured somehow by
120	 * all allocations for memory areas to be exposed to the chip ...
121	 *
122	 * Note:
123	 * Don't be surprised to get "Setting latency timer..." messages every
124	 * time when PCI busmastering is enabled for the chip.
125	 * The chip has its PCI latency timer RO fixed at 0 - which is not a
126	 * problem here, because it is never requesting _burst_ transactions.
127	 */
128
129/* ------------------------------------------ */
130
131/* VLSI_PCIIRMISC: IR Miscellaneous Register (u8, rw) */
132
133/* legacy UART emulation - not used by this driver - would require:
134 * (see below for some register-value definitions)
135 *
136 *	- IRMISC_UARTEN must be set to enable UART address decoding
137 *	- IRMISC_UARTSEL configured
138 *	- IRCFG_MASTER must be cleared
139 *	- IRCFG_SIR must be set
140 *	- IRENABLE_PHYANDCLOCK must be asserted 0->1 (and hence IRENABLE_SIR_ON)
141 */
142
143enum vlsi_pci_irmisc {
144
145	/* IR transceiver control */
146
147	IRMISC_IRRAIL		= 0x40,		/* (ro?) IR rail power indication (and control?)
148						 * 0=3.3V / 1=5V. Probably set during power-on?
149						 * unclear - not touched by driver */
150	IRMISC_IRPD		= 0x08,		/* transceiver power down, if set */
151
152	/* legacy UART control */
153
154	IRMISC_UARTTST		= 0x80,		/* UART test mode - "always write 0" */
155	IRMISC_UARTEN		= 0x04,		/* enable UART address decoding */
156
157	/* bits [1:0] IRMISC_UARTSEL to select legacy UART address */
158
159	IRMISC_UARTSEL_3f8	= 0x00,
160	IRMISC_UARTSEL_2f8	= 0x01,
161	IRMISC_UARTSEL_3e8	= 0x02,
162	IRMISC_UARTSEL_2e8	= 0x03
163};
164
165/* ================================================================ */
166
167/* registers mapped to 32 byte PCI IO space */
168
169/* note: better access all registers at the indicated u8/u16 size
170 *	 although some of them contain only 1 byte of information.
171 *	 some of them (particaluarly PROMPT and IRCFG) ignore
172 *	 access when using the wrong addressing mode!
173 */
174
175enum vlsi_pio_regs {
176	VLSI_PIO_IRINTR		= 0x00,		/* interrupt enable/request (u8, rw) */
177	VLSI_PIO_RINGPTR	= 0x02,		/* rx/tx ring pointer (u16, ro) */
178	VLSI_PIO_RINGBASE	= 0x04,		/* [23:10] of ring address (u16, rw) */
179	VLSI_PIO_RINGSIZE	= 0x06,		/* rx/tx ring size (u16, rw) */
180	VLSI_PIO_PROMPT		= 0x08, 	/* triggers ring processing (u16, wo) */
181	/* 0x0a-0x0f: reserved / duplicated UART regs */
182	VLSI_PIO_IRCFG		= 0x10,		/* configuration select (u16, rw) */
183	VLSI_PIO_SIRFLAG	= 0x12,		/* BOF/EOF for filtered SIR (u16, ro) */
184	VLSI_PIO_IRENABLE	= 0x14,		/* enable and status register (u16, rw/ro) */
185	VLSI_PIO_PHYCTL		= 0x16,		/* physical layer current status (u16, ro) */
186	VLSI_PIO_NPHYCTL	= 0x18,		/* next physical layer select (u16, rw) */
187	VLSI_PIO_MAXPKT		= 0x1a,		/* [11:0] max len for packet receive (u16, rw) */
188	VLSI_PIO_RCVBCNT	= 0x1c		/* current receive-FIFO byte count (u16, ro) */
189	/* 0x1e-0x1f: reserved / duplicated UART regs */
190};
191
192/* ------------------------------------------ */
193
194/* VLSI_PIO_IRINTR: Interrupt Register (u8, rw) */
195
196/* enable-bits:
197 *		1 = enable / 0 = disable
198 * interrupt condition bits:
199 * 		set according to corresponding interrupt source
200 *		(regardless of the state of the enable bits)
201 *		enable bit status indicates whether interrupt gets raised
202 *		write-to-clear
203 * note: RPKTINT and TPKTINT behave different in legacy UART mode (which we don't use :-)
204 */
205
206enum vlsi_pio_irintr {
207	IRINTR_ACTEN	= 0x80,	/* activity interrupt enable */
208	IRINTR_ACTIVITY	= 0x40,	/* activity monitor (traffic detected) */
209	IRINTR_RPKTEN	= 0x20,	/* receive packet interrupt enable*/
210	IRINTR_RPKTINT	= 0x10,	/* rx-packet transferred from fifo to memory finished */
211	IRINTR_TPKTEN	= 0x08,	/* transmit packet interrupt enable */
212	IRINTR_TPKTINT	= 0x04,	/* last bit of tx-packet+crc shifted to ir-pulser */
213	IRINTR_OE_EN	= 0x02,	/* UART rx fifo overrun error interrupt enable */
214	IRINTR_OE_INT	= 0x01	/* UART rx fifo overrun error (read LSR to clear) */
215};
216
217/* we use this mask to check whether the (shared PCI) interrupt is ours */
218
219#define IRINTR_INT_MASK		(IRINTR_ACTIVITY|IRINTR_RPKTINT|IRINTR_TPKTINT)
220
221/* ------------------------------------------ */
222
223/* VLSI_PIO_RINGPTR: Ring Pointer Read-Back Register (u16, ro) */
224
225/* _both_ ring pointers are indices relative to the _entire_ rx,tx-ring!
226 * i.e. the referenced descriptor is located
227 * at RINGBASE + PTR * sizeof(descr) for rx and tx
228 * therefore, the tx-pointer has offset MAX_RING_DESCR
229 */
230
231#define MAX_RING_DESCR		64	/* tx, rx rings may contain up to 64 descr each */
232
233#define RINGPTR_RX_MASK		(MAX_RING_DESCR-1)
234#define RINGPTR_TX_MASK		((MAX_RING_DESCR-1)<<8)
235
236#define RINGPTR_GET_RX(p)	((p)&RINGPTR_RX_MASK)
237#define RINGPTR_GET_TX(p)	(((p)&RINGPTR_TX_MASK)>>8)
238
239/* ------------------------------------------ */
240
241/* VLSI_PIO_RINGBASE: Ring Pointer Base Address Register (u16, ro) */
242
243/* Contains [23:10] part of the ring base (bus-) address
244 * which must be 1k-alinged. [31:24] is taken from
245 * VLSI_PCI_MSTRPAGE above.
246 * The controller initiates non-burst PCI BM cycles to
247 * fetch and update the descriptors in the ring.
248 * Once fetched, the descriptor remains cached onchip
249 * until it gets closed and updated due to the ring
250 * processing state machine.
251 * The entire ring area is split in rx and tx areas with each
252 * area consisting of 64 descriptors of 8 bytes each.
253 * The rx(tx) ring is located at ringbase+0 (ringbase+64*8).
254 */
255
256#define BUS_TO_RINGBASE(p)	(((p)>>10)&0x3fff)
257
258/* ------------------------------------------ */
259
260/* VLSI_PIO_RINGSIZE: Ring Size Register (u16, rw) */
261
262/* bit mask to indicate the ring size to be used for rx and tx.
263 * 	possible values		encoded bits
264 *		 4		   0000
265 *		 8		   0001
266 *		16		   0011
267 *		32		   0111
268 *		64		   1111
269 * located at [15:12] for tx and [11:8] for rx ([7:0] unused)
270 *
271 * note: probably a good idea to have IRCFG_MSTR cleared when writing
272 *	 this so the state machines are stopped and the RINGPTR is reset!
273 */
274
275#define SIZE_TO_BITS(num)		((((num)-1)>>2)&0x0f)
276#define TX_RX_TO_RINGSIZE(tx,rx)	((SIZE_TO_BITS(tx)<<12)|(SIZE_TO_BITS(rx)<<8))
277#define RINGSIZE_TO_RXSIZE(rs)		((((rs)&0x0f00)>>6)+4)
278#define RINGSIZE_TO_TXSIZE(rs)		((((rs)&0xf000)>>10)+4)
279
280
281/* ------------------------------------------ */
282
283/* VLSI_PIO_PROMPT: Ring Prompting Register (u16, write-to-start) */
284
285/* writing any value kicks the ring processing state machines
286 * for both tx, rx rings as follows:
287 * 	- active rings (currently owning an active descriptor)
288 *	  ignore the prompt and continue
289 *	- idle rings fetch the next descr from the ring and start
290 *	  their processing
291 */
292
293/* ------------------------------------------ */
294
295/* VLSI_PIO_IRCFG: IR Config Register (u16, rw) */
296
297/* notes:
298 *	- not more than one SIR/MIR/FIR bit must be set at any time
299 *	- SIR, MIR, FIR and CRC16 select the configuration which will
300 *	  be applied on next 0->1 transition of IRENABLE_PHYANDCLOCK (see below).
301 *	- besides allowing the PCI interface to execute busmaster cycles
302 *	  and therefore the ring SM to operate, the MSTR bit has side-effects:
303 *	  when MSTR is cleared, the RINGPTR's get reset and the legacy UART mode
304 *	  (in contrast to busmaster access mode) gets enabled.
305 *	- clearing ENRX or setting ENTX while data is received may stall the
306 *	  receive fifo until ENRX reenabled _and_ another packet arrives
307 *	- SIRFILT means the chip performs the required unwrapping of hardware
308 *	  headers (XBOF's, BOF/EOF) and un-escaping in the _receive_ direction.
309 *	  Only the resulting IrLAP payload is copied to the receive buffers -
310 *	  but with the 16bit FCS still encluded. Question remains, whether it
311 *	  was already checked or we should do it before passing the packet to IrLAP?
312 */
313
314enum vlsi_pio_ircfg {
315	IRCFG_LOOP	= 0x4000,	/* enable loopback test mode */
316	IRCFG_ENTX	= 0x1000,	/* transmit enable */
317	IRCFG_ENRX	= 0x0800,	/* receive enable */
318	IRCFG_MSTR	= 0x0400,	/* master enable */
319	IRCFG_RXANY	= 0x0200,	/* receive any packet */
320	IRCFG_CRC16	= 0x0080,	/* 16bit (not 32bit) CRC select for MIR/FIR */
321	IRCFG_FIR	= 0x0040,	/* FIR 4PPM encoding mode enable */
322	IRCFG_MIR	= 0x0020,	/* MIR HDLC encoding mode enable */
323	IRCFG_SIR	= 0x0010,	/* SIR encoding mode enable */
324	IRCFG_SIRFILT	= 0x0008,	/* enable SIR decode filter (receiver unwrapping) */
325	IRCFG_SIRTEST	= 0x0004,	/* allow SIR decode filter when not in SIR mode */
326	IRCFG_TXPOL	= 0x0002,	/* invert tx polarity when set */
327	IRCFG_RXPOL	= 0x0001	/* invert rx polarity when set */
328};
329
330/* ------------------------------------------ */
331
332/* VLSI_PIO_SIRFLAG: SIR Flag Register (u16, ro) */
333
334/* register contains hardcoded BOF=0xc0 at [7:0] and EOF=0xc1 at [15:8]
335 * which is used for unwrapping received frames in SIR decode-filter mode
336 */
337
338/* ------------------------------------------ */
339
340/* VLSI_PIO_IRENABLE: IR Enable Register (u16, rw/ro) */
341
342/* notes:
343 *	- IREN acts as gate for latching the configured IR mode information
344 *	  from IRCFG and IRPHYCTL when IREN=reset and applying them when
345 *	  IREN gets set afterwards.
346 *	- ENTXST reflects IRCFG_ENTX
347 *	- ENRXST = IRCFG_ENRX && (!IRCFG_ENTX || IRCFG_LOOP)
348 */
349
350enum vlsi_pio_irenable {
351	IRENABLE_PHYANDCLOCK	= 0x8000,  /* enable IR phy and gate the mode config (rw) */
352	IRENABLE_CFGER		= 0x4000,  /* mode configuration error (ro) */
353	IRENABLE_FIR_ON		= 0x2000,  /* FIR on status (ro) */
354	IRENABLE_MIR_ON		= 0x1000,  /* MIR on status (ro) */
355	IRENABLE_SIR_ON		= 0x0800,  /* SIR on status (ro) */
356	IRENABLE_ENTXST		= 0x0400,  /* transmit enable status (ro) */
357	IRENABLE_ENRXST		= 0x0200,  /* Receive enable status (ro) */
358	IRENABLE_CRC16_ON	= 0x0100   /* 16bit (not 32bit) CRC enabled status (ro) */
359};
360
361#define	  IRENABLE_MASK	    0xff00  /* Read mask */
362
363/* ------------------------------------------ */
364
365/* VLSI_PIO_PHYCTL: IR Physical Layer Current Control Register (u16, ro) */
366
367/* read-back of the currently applied physical layer status.
368 * applied from VLSI_PIO_NPHYCTL at rising edge of IRENABLE_PHYANDCLOCK
369 * contents identical to VLSI_PIO_NPHYCTL (see below)
370 */
371
372/* ------------------------------------------ */
373
374/* VLSI_PIO_NPHYCTL: IR Physical Layer Next Control Register (u16, rw) */
375
376/* latched during IRENABLE_PHYANDCLOCK=0 and applied at 0-1 transition
377 *
378 * consists of BAUD[15:10], PLSWID[9:5] and PREAMB[4:0] bits defined as follows:
379 *
380 * SIR-mode:	BAUD = (115.2kHz / baudrate) - 1
381 *		PLSWID = (pulsetime * freq / (BAUD+1)) - 1
382 *			where pulsetime is the requested IrPHY pulse width
383 *			and freq is 8(16)MHz for 40(48)MHz primary input clock
384 *		PREAMB: don't care for SIR
385 *
386 *		The nominal SIR pulse width is 3/16 bit time so we have PLSWID=12
387 *		fixed for all SIR speeds at 40MHz input clock (PLSWID=24 at 48MHz).
388 *		IrPHY also allows shorter pulses down to the nominal pulse duration
389 *		at 115.2kbaud (minus some tolerance) which is 1.41 usec.
390 *		Using the expression PLSWID = 12/(BAUD+1)-1 (multiplied by two for 48MHz)
391 *		we get the minimum acceptable PLSWID values according to the VLSI
392 *		specification, which provides 1.5 usec pulse width for all speeds (except
393 *		for 2.4kbaud getting 6usec). This is fine with IrPHY v1.3 specs and
394 *		reduces the transceiver power which drains the battery. At 9.6kbaud for
395 *		example this amounts to more than 90% battery power saving!
396 *
397 * MIR-mode:	BAUD = 0
398 *		PLSWID = 9(10) for 40(48) MHz input clock
399 *			to get nominal MIR pulse width
400 *		PREAMB = 1
401 *
402 * FIR-mode:	BAUD = 0
403 *		PLSWID: don't care
404 *		PREAMB = 15
405 */
406
407#define PHYCTL_BAUD_SHIFT	10
408#define PHYCTL_BAUD_MASK	0xfc00
409#define PHYCTL_PLSWID_SHIFT	5
410#define PHYCTL_PLSWID_MASK	0x03e0
411#define PHYCTL_PREAMB_SHIFT	0
412#define PHYCTL_PREAMB_MASK	0x001f
413
414#define PHYCTL_TO_BAUD(bwp)	(((bwp)&PHYCTL_BAUD_MASK)>>PHYCTL_BAUD_SHIFT)
415#define PHYCTL_TO_PLSWID(bwp)	(((bwp)&PHYCTL_PLSWID_MASK)>>PHYCTL_PLSWID_SHIFT)
416#define PHYCTL_TO_PREAMB(bwp)	(((bwp)&PHYCTL_PREAMB_MASK)>>PHYCTL_PREAMB_SHIFT)
417
418#define BWP_TO_PHYCTL(b,w,p)	((((b)<<PHYCTL_BAUD_SHIFT)&PHYCTL_BAUD_MASK) \
419				 | (((w)<<PHYCTL_PLSWID_SHIFT)&PHYCTL_PLSWID_MASK) \
420				 | (((p)<<PHYCTL_PREAMB_SHIFT)&PHYCTL_PREAMB_MASK))
421
422#define BAUD_BITS(br)		((115200/(br))-1)
423
424static inline unsigned
425calc_width_bits(unsigned baudrate, unsigned widthselect, unsigned clockselect)
426{
427	unsigned	tmp;
428
429	if (widthselect)	/* nominal 3/16 puls width */
430		return (clockselect) ? 12 : 24;
431
432	tmp = ((clockselect) ? 12 : 24) / (BAUD_BITS(baudrate)+1);
433
434	/* intermediate result of integer division needed here */
435
436	return (tmp>0) ? (tmp-1) : 0;
437}
438
439#define PHYCTL_SIR(br,ws,cs)	BWP_TO_PHYCTL(BAUD_BITS(br),calc_width_bits((br),(ws),(cs)),0)
440#define PHYCTL_MIR(cs)		BWP_TO_PHYCTL(0,((cs)?9:10),1)
441#define PHYCTL_FIR		BWP_TO_PHYCTL(0,0,15)
442
443/* quite ugly, I know. But implementing these calculations here avoids
444 * having magic numbers in the code and allows some playing with pulsewidths
445 * without risk to violate the standards.
446 * FWIW, here is the table for reference:
447 *
448 * baudrate	BAUD	min-PLSWID	nom-PLSWID	PREAMB
449 *     2400	  47	   0(0)		   12(24)	   0
450 *     9600	  11	   0(0)		   12(24)	   0
451 *    19200	   5	   1(2)		   12(24)	   0
452 *    38400	   2	   3(6)	           12(24)	   0
453 *    57600	   1	   5(10)	   12(24)	   0
454 *   115200	   0	  11(22)	   12(24)	   0
455 *	MIR	   0	    -		    9(10)	   1
456 *	FIR	   0        -               0		  15
457 *
458 * note: x(y) means x-value for 40MHz / y-value for 48MHz primary input clock
459 */
460
461/* ------------------------------------------ */
462
463
464/* VLSI_PIO_MAXPKT: Maximum Packet Length register (u16, rw) */
465
466/* maximum acceptable length for received packets */
467
468/* hw imposed limitation - register uses only [11:0] */
469#define MAX_PACKET_LENGTH	0x0fff
470
471/* IrLAP I-field (apparently not defined elsewhere) */
472#define IRDA_MTU		2048
473
474/* complete packet consists of A(1)+C(1)+I(<=IRDA_MTU) */
475#define IRLAP_SKB_ALLOCSIZE	(1+1+IRDA_MTU)
476
477/* the buffers we use to exchange frames with the hardware need to be
478 * larger than IRLAP_SKB_ALLOCSIZE because we may have up to 4 bytes FCS
479 * appended and, in SIR mode, a lot of frame wrapping bytes. The worst
480 * case appears to be a SIR packet with I-size==IRDA_MTU and all bytes
481 * requiring to be escaped to provide transparency. Furthermore, the peer
482 * might ask for quite a number of additional XBOFs:
483 *	up to 115+48 XBOFS		 163
484 *	regular BOF			   1
485 *	A-field				   1
486 *	C-field				   1
487 *	I-field, IRDA_MTU, all escaped	4096
488 *	FCS (16 bit at SIR, escaped)	   4
489 *	EOF				   1
490 * AFAICS nothing in IrLAP guarantees A/C field not to need escaping
491 * (f.e. 0xc0/0xc1 - i.e. BOF/EOF - are legal values there) so in the
492 * worst case we have 4269 bytes total frame size.
493 * However, the VLSI uses 12 bits only for all buffer length values,
494 * which limits the maximum useable buffer size <= 4095.
495 * Note this is not a limitation in the receive case because we use
496 * the SIR filtering mode where the hw unwraps the frame and only the
497 * bare packet+fcs is stored into the buffer - in contrast to the SIR
498 * tx case where we have to pass frame-wrapped packets to the hw.
499 * If this would ever become an issue in real life, the only workaround
500 * I see would be using the legacy UART emulation in SIR mode.
501 */
502
503#define XFER_BUF_SIZE		MAX_PACKET_LENGTH
504
505/* ------------------------------------------ */
506
507/* VLSI_PIO_RCVBCNT: Receive Byte Count Register (u16, ro) */
508
509/* receive packet counter gets incremented on every non-filtered
510 * byte which was put in the receive fifo and reset for each
511 * new packet. Used to decide whether we are just in the middle
512 * of receiving
513 */
514
515/* better apply the [11:0] mask when reading, as some docs say the
516 * reserved [15:12] would return 1 when reading - which is wrong AFAICS
517 */
518#define RCVBCNT_MASK	0x0fff
519
520/******************************************************************/
521
522/* descriptors for rx/tx ring
523 *
524 * accessed by hardware - don't change!
525 *
526 * the descriptor is owned by hardware, when the ACTIVE status bit
527 * is set and nothing (besides reading status to test the bit)
528 * shall be done. The bit gets cleared by hw, when the descriptor
529 * gets closed. Premature reaping of descriptors owned be the chip
530 * can be achieved by disabling IRCFG_MSTR
531 *
532 * Attention: Writing addr overwrites status!
533 *
534 * ### FIXME: depends on endianess (but there ain't no non-i586 ob800 ;-)
535 */
536
537struct ring_descr_hw {
538	volatile __le16	rd_count;	/* tx/rx count [11:0] */
539	__le16		reserved;
540	union {
541		__le32	addr;		/* [23:0] of the buffer's busaddress */
542		struct {
543			u8		addr_res[3];
544			volatile u8	status;		/* descriptor status */
545		} __packed rd_s;
546	} __packed rd_u;
547} __packed;
548
549#define rd_addr		rd_u.addr
550#define rd_status	rd_u.rd_s.status
551
552/* ring descriptor status bits */
553
554#define RD_ACTIVE		0x80	/* descriptor owned by hw (both TX,RX) */
555
556/* TX ring descriptor status */
557
558#define	RD_TX_DISCRC		0x40	/* do not send CRC (for SIR) */
559#define	RD_TX_BADCRC		0x20	/* force a bad CRC */
560#define	RD_TX_PULSE		0x10	/* send indication pulse after this frame (MIR/FIR) */
561#define	RD_TX_FRCEUND		0x08	/* force underrun */
562#define	RD_TX_CLRENTX		0x04	/* clear ENTX after this frame */
563#define	RD_TX_UNDRN		0x01	/* TX fifo underrun (probably PCI problem) */
564
565/* RX ring descriptor status */
566
567#define RD_RX_PHYERR		0x40	/* physical encoding error */
568#define RD_RX_CRCERR		0x20	/* CRC error (MIR/FIR) */
569#define RD_RX_LENGTH		0x10	/* frame exceeds buffer length */
570#define RD_RX_OVER		0x08	/* RX fifo overrun (probably PCI problem) */
571#define RD_RX_SIRBAD		0x04	/* EOF missing: BOF follows BOF (SIR, filtered) */
572
573#define RD_RX_ERROR		0x7c	/* any error in received frame */
574
575/* the memory required to hold the 2 descriptor rings */
576#define HW_RING_AREA_SIZE	(2 * MAX_RING_DESCR * sizeof(struct ring_descr_hw))
577
578/******************************************************************/
579
580/* sw-ring descriptors consists of a bus-mapped transfer buffer with
581 * associated skb and a pointer to the hw entry descriptor
582 */
583
584struct ring_descr {
585	struct ring_descr_hw	*hw;
586	struct sk_buff		*skb;
587	void			*buf;
588};
589
590/* wrappers for operations on hw-exposed ring descriptors
591 * access to the hw-part of the descriptors must use these.
592 */
593
594static inline int rd_is_active(struct ring_descr *rd)
595{
596	return (rd->hw->rd_status & RD_ACTIVE) != 0;
597}
598
599static inline void rd_activate(struct ring_descr *rd)
600{
601	rd->hw->rd_status |= RD_ACTIVE;
602}
603
604static inline void rd_set_status(struct ring_descr *rd, u8 s)
605{
606	rd->hw->rd_status = s;	 /* may pass ownership to the hardware */
607}
608
609static inline void rd_set_addr_status(struct ring_descr *rd, dma_addr_t a, u8 s)
610{
611	/* order is important for two reasons:
612	 *  - overlayed: writing addr overwrites status
613	 *  - we want to write status last so we have valid address in
614	 *    case status has RD_ACTIVE set
615	 */
616
617	if ((a & ~DMA_MASK_MSTRPAGE)>>24 != MSTRPAGE_VALUE) {
618		IRDA_ERROR("%s: pci busaddr inconsistency!\n", __func__);
619		dump_stack();
620		return;
621	}
622
623	a &= DMA_MASK_MSTRPAGE;  /* clear highbyte to make sure we won't write
624				  * to status - just in case MSTRPAGE_VALUE!=0
625				  */
626	rd->hw->rd_addr = cpu_to_le32(a);
627	wmb();
628	rd_set_status(rd, s);	 /* may pass ownership to the hardware */
629}
630
631static inline void rd_set_count(struct ring_descr *rd, u16 c)
632{
633	rd->hw->rd_count = cpu_to_le16(c);
634}
635
636static inline u8 rd_get_status(struct ring_descr *rd)
637{
638	return rd->hw->rd_status;
639}
640
641static inline dma_addr_t rd_get_addr(struct ring_descr *rd)
642{
643	dma_addr_t	a;
644
645	a = le32_to_cpu(rd->hw->rd_addr);
646	return (a & DMA_MASK_MSTRPAGE) | (MSTRPAGE_VALUE << 24);
647}
648
649static inline u16 rd_get_count(struct ring_descr *rd)
650{
651	return le16_to_cpu(rd->hw->rd_count);
652}
653
654/******************************************************************/
655
656/* sw descriptor rings for rx, tx:
657 *
658 * operations follow producer-consumer paradigm, with the hw
659 * in the middle doing the processing.
660 * ring size must be power of two.
661 *
662 * producer advances r->tail after inserting for processing
663 * consumer advances r->head after removing processed rd
664 * ring is empty if head==tail / full if (tail+1)==head
665 */
666
667struct vlsi_ring {
668	struct pci_dev		*pdev;
669	int			dir;
670	unsigned		len;
671	unsigned		size;
672	unsigned		mask;
673	atomic_t		head, tail;
674	struct ring_descr	*rd;
675};
676
677/* ring processing helpers */
678
679static inline struct ring_descr *ring_last(struct vlsi_ring *r)
680{
681	int t;
682
683	t = atomic_read(&r->tail) & r->mask;
684	return (((t+1) & r->mask) == (atomic_read(&r->head) & r->mask)) ? NULL : &r->rd[t];
685}
686
687static inline struct ring_descr *ring_put(struct vlsi_ring *r)
688{
689	atomic_inc(&r->tail);
690	return ring_last(r);
691}
692
693static inline struct ring_descr *ring_first(struct vlsi_ring *r)
694{
695	int h;
696
697	h = atomic_read(&r->head) & r->mask;
698	return (h == (atomic_read(&r->tail) & r->mask)) ? NULL : &r->rd[h];
699}
700
701static inline struct ring_descr *ring_get(struct vlsi_ring *r)
702{
703	atomic_inc(&r->head);
704	return ring_first(r);
705}
706
707/******************************************************************/
708
709/* our private compound VLSI-PCI-IRDA device information */
710
711typedef struct vlsi_irda_dev {
712	struct pci_dev		*pdev;
713
714	struct irlap_cb		*irlap;
715
716	struct qos_info		qos;
717
718	unsigned		mode;
719	int			baud, new_baud;
720
721	dma_addr_t		busaddr;
722	void			*virtaddr;
723	struct vlsi_ring	*tx_ring, *rx_ring;
724
725	struct timeval		last_rx;
726
727	spinlock_t		lock;
728	struct mutex		mtx;
729
730	u8			resume_ok;
731	struct proc_dir_entry	*proc_entry;
732
733} vlsi_irda_dev_t;
734
735/********************************************************/
736
737/* the remapped error flags we use for returning from frame
738 * post-processing in vlsi_process_tx/rx() after it was completed
739 * by the hardware. These functions either return the >=0 number
740 * of transferred bytes in case of success or the negative (-)
741 * of the or'ed error flags.
742 */
743
744#define VLSI_TX_DROP		0x0001
745#define VLSI_TX_FIFO		0x0002
746
747#define VLSI_RX_DROP		0x0100
748#define VLSI_RX_OVER		0x0200
749#define VLSI_RX_LENGTH  	0x0400
750#define VLSI_RX_FRAME		0x0800
751#define VLSI_RX_CRC		0x1000
752
753/********************************************************/
754
755#endif /* IRDA_VLSI_FIR_H */
756
757