xref: /openbmc/linux/drivers/tty/serial/pmac_zilog.h (revision 2dd6532e)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __PMAC_ZILOG_H__
3 #define __PMAC_ZILOG_H__
4 
5 /*
6  * At most 2 ESCCs with 2 ports each
7  */
8 #define MAX_ZS_PORTS	4
9 
10 /*
11  * We wrap our port structure around the generic uart_port.
12  */
13 #define NUM_ZSREGS    17
14 
15 struct uart_pmac_port {
16 	struct uart_port		port;
17 	struct uart_pmac_port		*mate;
18 
19 #ifdef CONFIG_PPC_PMAC
20 	/* macio_dev for the escc holding this port (maybe be null on
21 	 * early inited port)
22 	 */
23 	struct macio_dev		*dev;
24 	/* device node to this port, this points to one of 2 childs
25 	 * of "escc" node (ie. ch-a or ch-b)
26 	 */
27 	struct device_node		*node;
28 #else
29 	struct platform_device		*pdev;
30 #endif
31 
32 	/* Port type as obtained from device tree (IRDA, modem, ...) */
33 	int				port_type;
34 	u8				curregs[NUM_ZSREGS];
35 
36 	unsigned int			flags;
37 #define PMACZILOG_FLAG_IS_CONS		0x00000001
38 #define PMACZILOG_FLAG_IS_KGDB		0x00000002
39 #define PMACZILOG_FLAG_MODEM_STATUS	0x00000004
40 #define PMACZILOG_FLAG_IS_CHANNEL_A	0x00000008
41 #define PMACZILOG_FLAG_REGS_HELD	0x00000010
42 #define PMACZILOG_FLAG_TX_STOPPED	0x00000020
43 #define PMACZILOG_FLAG_TX_ACTIVE	0x00000040
44 #define PMACZILOG_FLAG_IS_IRDA		0x00000100
45 #define PMACZILOG_FLAG_IS_INTMODEM	0x00000200
46 #define PMACZILOG_FLAG_RSRC_REQUESTED	0x00000800
47 #define PMACZILOG_FLAG_IS_OPEN		0x00002000
48 #define PMACZILOG_FLAG_IS_EXTCLK	0x00008000
49 #define PMACZILOG_FLAG_BREAK		0x00010000
50 
51 	unsigned char			parity_mask;
52 	unsigned char			prev_status;
53 
54 	volatile u8			__iomem *control_reg;
55 	volatile u8			__iomem *data_reg;
56 
57 	unsigned char			irq_name[8];
58 };
59 
60 #define to_pmz(p) ((struct uart_pmac_port *)(p))
61 
62 static inline struct uart_pmac_port *pmz_get_port_A(struct uart_pmac_port *uap)
63 {
64 	if (uap->flags & PMACZILOG_FLAG_IS_CHANNEL_A)
65 		return uap;
66 	return uap->mate;
67 }
68 
69 /*
70  * Register accessors. Note that we don't need to enforce a recovery
71  * delay on PCI PowerMac hardware, it's dealt in HW by the MacIO chip,
72  * though if we try to use this driver on older machines, we might have
73  * to add it back
74  */
75 static inline u8 read_zsreg(struct uart_pmac_port *port, u8 reg)
76 {
77 	if (reg != 0)
78 		writeb(reg, port->control_reg);
79 	return readb(port->control_reg);
80 }
81 
82 static inline void write_zsreg(struct uart_pmac_port *port, u8 reg, u8 value)
83 {
84 	if (reg != 0)
85 		writeb(reg, port->control_reg);
86 	writeb(value, port->control_reg);
87 }
88 
89 static inline u8 read_zsdata(struct uart_pmac_port *port)
90 {
91 	return readb(port->data_reg);
92 }
93 
94 static inline void write_zsdata(struct uart_pmac_port *port, u8 data)
95 {
96 	writeb(data, port->data_reg);
97 }
98 
99 static inline void zssync(struct uart_pmac_port *port)
100 {
101 	(void)readb(port->control_reg);
102 }
103 
104 /* Conversion routines to/from brg time constants from/to bits
105  * per second.
106  */
107 #define BRG_TO_BPS(brg, freq) ((freq) / 2 / ((brg) + 2))
108 #define BPS_TO_BRG(bps, freq) ((((freq) + (bps)) / (2 * (bps))) - 2)
109 
110 #define ZS_CLOCK         3686400	/* Z8530 RTxC input clock rate */
111 
112 /* The Zilog register set */
113 
114 #define	FLAG	0x7e
115 
116 /* Write Register 0 */
117 #define	R0	0		/* Register selects */
118 #define	R1	1
119 #define	R2	2
120 #define	R3	3
121 #define	R4	4
122 #define	R5	5
123 #define	R6	6
124 #define	R7	7
125 #define	R8	8
126 #define	R9	9
127 #define	R10	10
128 #define	R11	11
129 #define	R12	12
130 #define	R13	13
131 #define	R14	14
132 #define	R15	15
133 #define	R7P	16
134 
135 #define	NULLCODE	0	/* Null Code */
136 #define	POINT_HIGH	0x8	/* Select upper half of registers */
137 #define	RES_EXT_INT	0x10	/* Reset Ext. Status Interrupts */
138 #define	SEND_ABORT	0x18	/* HDLC Abort */
139 #define	RES_RxINT_FC	0x20	/* Reset RxINT on First Character */
140 #define	RES_Tx_P	0x28	/* Reset TxINT Pending */
141 #define	ERR_RES		0x30	/* Error Reset */
142 #define	RES_H_IUS	0x38	/* Reset highest IUS */
143 
144 #define	RES_Rx_CRC	0x40	/* Reset Rx CRC Checker */
145 #define	RES_Tx_CRC	0x80	/* Reset Tx CRC Checker */
146 #define	RES_EOM_L	0xC0	/* Reset EOM latch */
147 
148 /* Write Register 1 */
149 
150 #define	EXT_INT_ENAB	0x1	/* Ext Int Enable */
151 #define	TxINT_ENAB	0x2	/* Tx Int Enable */
152 #define	PAR_SPEC	0x4	/* Parity is special condition */
153 
154 #define	RxINT_DISAB	0	/* Rx Int Disable */
155 #define	RxINT_FCERR	0x8	/* Rx Int on First Character Only or Error */
156 #define	INT_ALL_Rx	0x10	/* Int on all Rx Characters or error */
157 #define	INT_ERR_Rx	0x18	/* Int on error only */
158 #define RxINT_MASK	0x18
159 
160 #define	WT_RDY_RT	0x20	/* W/Req reflects recv if 1, xmit if 0 */
161 #define	WT_FN_RDYFN	0x40	/* W/Req pin is DMA request if 1, wait if 0 */
162 #define	WT_RDY_ENAB	0x80	/* Enable W/Req pin */
163 
164 /* Write Register #2 (Interrupt Vector) */
165 
166 /* Write Register 3 */
167 
168 #define	RxENABLE	0x1	/* Rx Enable */
169 #define	SYNC_L_INH	0x2	/* Sync Character Load Inhibit */
170 #define	ADD_SM		0x4	/* Address Search Mode (SDLC) */
171 #define	RxCRC_ENAB	0x8	/* Rx CRC Enable */
172 #define	ENT_HM		0x10	/* Enter Hunt Mode */
173 #define	AUTO_ENAB	0x20	/* Auto Enables */
174 #define	Rx5		0x0	/* Rx 5 Bits/Character */
175 #define	Rx7		0x40	/* Rx 7 Bits/Character */
176 #define	Rx6		0x80	/* Rx 6 Bits/Character */
177 #define	Rx8		0xc0	/* Rx 8 Bits/Character */
178 #define RxN_MASK	0xc0
179 
180 /* Write Register 4 */
181 
182 #define	PAR_ENAB	0x1	/* Parity Enable */
183 #define	PAR_EVEN	0x2	/* Parity Even/Odd* */
184 
185 #define	SYNC_ENAB	0	/* Sync Modes Enable */
186 #define	SB1		0x4	/* 1 stop bit/char */
187 #define	SB15		0x8	/* 1.5 stop bits/char */
188 #define	SB2		0xc	/* 2 stop bits/char */
189 #define SB_MASK		0xc
190 
191 #define	MONSYNC		0	/* 8 Bit Sync character */
192 #define	BISYNC		0x10	/* 16 bit sync character */
193 #define	SDLC		0x20	/* SDLC Mode (01111110 Sync Flag) */
194 #define	EXTSYNC		0x30	/* External Sync Mode */
195 
196 #define	X1CLK		0x0	/* x1 clock mode */
197 #define	X16CLK		0x40	/* x16 clock mode */
198 #define	X32CLK		0x80	/* x32 clock mode */
199 #define	X64CLK		0xC0	/* x64 clock mode */
200 #define XCLK_MASK	0xC0
201 
202 /* Write Register 5 */
203 
204 #define	TxCRC_ENAB	0x1	/* Tx CRC Enable */
205 #define	RTS		0x2	/* RTS */
206 #define	SDLC_CRC	0x4	/* SDLC/CRC-16 */
207 #define	TxENABLE	0x8	/* Tx Enable */
208 #define	SND_BRK		0x10	/* Send Break */
209 #define	Tx5		0x0	/* Tx 5 bits (or less)/character */
210 #define	Tx7		0x20	/* Tx 7 bits/character */
211 #define	Tx6		0x40	/* Tx 6 bits/character */
212 #define	Tx8		0x60	/* Tx 8 bits/character */
213 #define TxN_MASK	0x60
214 #define	DTR		0x80	/* DTR */
215 
216 /* Write Register 6 (Sync bits 0-7/SDLC Address Field) */
217 
218 /* Write Register 7 (Sync bits 8-15/SDLC 01111110) */
219 
220 /* Write Register 7' (Some enhanced feature control) */
221 #define	ENEXREAD	0x40	/* Enable read of some write registers */
222 
223 /* Write Register 8 (transmit buffer) */
224 
225 /* Write Register 9 (Master interrupt control) */
226 #define	VIS	1	/* Vector Includes Status */
227 #define	NV	2	/* No Vector */
228 #define	DLC	4	/* Disable Lower Chain */
229 #define	MIE	8	/* Master Interrupt Enable */
230 #define	STATHI	0x10	/* Status high */
231 #define	NORESET	0	/* No reset on write to R9 */
232 #define	CHRB	0x40	/* Reset channel B */
233 #define	CHRA	0x80	/* Reset channel A */
234 #define	FHWRES	0xc0	/* Force hardware reset */
235 
236 /* Write Register 10 (misc control bits) */
237 #define	BIT6	1	/* 6 bit/8bit sync */
238 #define	LOOPMODE 2	/* SDLC Loop mode */
239 #define	ABUNDER	4	/* Abort/flag on SDLC xmit underrun */
240 #define	MARKIDLE 8	/* Mark/flag on idle */
241 #define	GAOP	0x10	/* Go active on poll */
242 #define	NRZ	0	/* NRZ mode */
243 #define	NRZI	0x20	/* NRZI mode */
244 #define	FM1	0x40	/* FM1 (transition = 1) */
245 #define	FM0	0x60	/* FM0 (transition = 0) */
246 #define	CRCPS	0x80	/* CRC Preset I/O */
247 
248 /* Write Register 11 (Clock Mode control) */
249 #define	TRxCXT	0	/* TRxC = Xtal output */
250 #define	TRxCTC	1	/* TRxC = Transmit clock */
251 #define	TRxCBR	2	/* TRxC = BR Generator Output */
252 #define	TRxCDP	3	/* TRxC = DPLL output */
253 #define	TRxCOI	4	/* TRxC O/I */
254 #define	TCRTxCP	0	/* Transmit clock = RTxC pin */
255 #define	TCTRxCP	8	/* Transmit clock = TRxC pin */
256 #define	TCBR	0x10	/* Transmit clock = BR Generator output */
257 #define	TCDPLL	0x18	/* Transmit clock = DPLL output */
258 #define	RCRTxCP	0	/* Receive clock = RTxC pin */
259 #define	RCTRxCP	0x20	/* Receive clock = TRxC pin */
260 #define	RCBR	0x40	/* Receive clock = BR Generator output */
261 #define	RCDPLL	0x60	/* Receive clock = DPLL output */
262 #define	RTxCX	0x80	/* RTxC Xtal/No Xtal */
263 
264 /* Write Register 12 (lower byte of baud rate generator time constant) */
265 
266 /* Write Register 13 (upper byte of baud rate generator time constant) */
267 
268 /* Write Register 14 (Misc control bits) */
269 #define	BRENAB	1	/* Baud rate generator enable */
270 #define	BRSRC	2	/* Baud rate generator source */
271 #define	DTRREQ	4	/* DTR/Request function */
272 #define	AUTOECHO 8	/* Auto Echo */
273 #define	LOOPBAK	0x10	/* Local loopback */
274 #define	SEARCH	0x20	/* Enter search mode */
275 #define	RMC	0x40	/* Reset missing clock */
276 #define	DISDPLL	0x60	/* Disable DPLL */
277 #define	SSBR	0x80	/* Set DPLL source = BR generator */
278 #define	SSRTxC	0xa0	/* Set DPLL source = RTxC */
279 #define	SFMM	0xc0	/* Set FM mode */
280 #define	SNRZI	0xe0	/* Set NRZI mode */
281 
282 /* Write Register 15 (external/status interrupt control) */
283 #define	EN85C30	1	/* Enable some 85c30-enhanced registers */
284 #define	ZCIE	2	/* Zero count IE */
285 #define	ENSTFIFO 4	/* Enable status FIFO (SDLC) */
286 #define	DCDIE	8	/* DCD IE */
287 #define	SYNCIE	0x10	/* Sync/hunt IE */
288 #define	CTSIE	0x20	/* CTS IE */
289 #define	TxUIE	0x40	/* Tx Underrun/EOM IE */
290 #define	BRKIE	0x80	/* Break/Abort IE */
291 
292 
293 /* Read Register 0 */
294 #define	Rx_CH_AV	0x1	/* Rx Character Available */
295 #define	ZCOUNT		0x2	/* Zero count */
296 #define	Tx_BUF_EMP	0x4	/* Tx Buffer empty */
297 #define	DCD		0x8	/* DCD */
298 #define	SYNC_HUNT	0x10	/* Sync/hunt */
299 #define	CTS		0x20	/* CTS */
300 #define	TxEOM		0x40	/* Tx underrun */
301 #define	BRK_ABRT	0x80	/* Break/Abort */
302 
303 /* Read Register 1 */
304 #define	ALL_SNT		0x1	/* All sent */
305 /* Residue Data for 8 Rx bits/char programmed */
306 #define	RES3		0x8	/* 0/3 */
307 #define	RES4		0x4	/* 0/4 */
308 #define	RES5		0xc	/* 0/5 */
309 #define	RES6		0x2	/* 0/6 */
310 #define	RES7		0xa	/* 0/7 */
311 #define	RES8		0x6	/* 0/8 */
312 #define	RES18		0xe	/* 1/8 */
313 #define	RES28		0x0	/* 2/8 */
314 /* Special Rx Condition Interrupts */
315 #define	PAR_ERR		0x10	/* Parity error */
316 #define	Rx_OVR		0x20	/* Rx Overrun Error */
317 #define	CRC_ERR		0x40	/* CRC/Framing Error */
318 #define	END_FR		0x80	/* End of Frame (SDLC) */
319 
320 /* Read Register 2 (channel b only) - Interrupt vector */
321 #define	CHB_Tx_EMPTY	0x00
322 #define	CHB_EXT_STAT	0x02
323 #define	CHB_Rx_AVAIL	0x04
324 #define	CHB_SPECIAL	0x06
325 #define	CHA_Tx_EMPTY	0x08
326 #define	CHA_EXT_STAT	0x0a
327 #define	CHA_Rx_AVAIL	0x0c
328 #define	CHA_SPECIAL	0x0e
329 #define	STATUS_MASK	0x06
330 
331 /* Read Register 3 (interrupt pending register) ch a only */
332 #define	CHBEXT	0x1		/* Channel B Ext/Stat IP */
333 #define	CHBTxIP	0x2		/* Channel B Tx IP */
334 #define	CHBRxIP	0x4		/* Channel B Rx IP */
335 #define	CHAEXT	0x8		/* Channel A Ext/Stat IP */
336 #define	CHATxIP	0x10		/* Channel A Tx IP */
337 #define	CHARxIP	0x20		/* Channel A Rx IP */
338 
339 /* Read Register 8 (receive data register) */
340 
341 /* Read Register 10  (misc status bits) */
342 #define	ONLOOP	2		/* On loop */
343 #define	LOOPSEND 0x10		/* Loop sending */
344 #define	CLK2MIS	0x40		/* Two clocks missing */
345 #define	CLK1MIS	0x80		/* One clock missing */
346 
347 /* Read Register 12 (lower byte of baud rate generator constant) */
348 
349 /* Read Register 13 (upper byte of baud rate generator constant) */
350 
351 /* Read Register 15 (value of WR 15) */
352 
353 /* Misc macros */
354 #define ZS_CLEARERR(port)    (write_zsreg(port, 0, ERR_RES))
355 #define ZS_CLEARFIFO(port)   do {                       \
356 				     read_zsdata(port); \
357 				     read_zsdata(port); \
358 				     read_zsdata(port); \
359 				} while(0)
360 
361 #define ZS_IS_CONS(UP)			((UP)->flags & PMACZILOG_FLAG_IS_CONS)
362 #define ZS_IS_KGDB(UP)			((UP)->flags & PMACZILOG_FLAG_IS_KGDB)
363 #define ZS_IS_CHANNEL_A(UP)		((UP)->flags & PMACZILOG_FLAG_IS_CHANNEL_A)
364 #define ZS_REGS_HELD(UP)		((UP)->flags & PMACZILOG_FLAG_REGS_HELD)
365 #define ZS_TX_STOPPED(UP)		((UP)->flags & PMACZILOG_FLAG_TX_STOPPED)
366 #define ZS_TX_ACTIVE(UP)		((UP)->flags & PMACZILOG_FLAG_TX_ACTIVE)
367 #define ZS_WANTS_MODEM_STATUS(UP)	((UP)->flags & PMACZILOG_FLAG_MODEM_STATUS)
368 #define ZS_IS_IRDA(UP)			((UP)->flags & PMACZILOG_FLAG_IS_IRDA)
369 #define ZS_IS_INTMODEM(UP)		((UP)->flags & PMACZILOG_FLAG_IS_INTMODEM)
370 #define ZS_IS_OPEN(UP)			((UP)->flags & PMACZILOG_FLAG_IS_OPEN)
371 #define ZS_IS_EXTCLK(UP)		((UP)->flags & PMACZILOG_FLAG_IS_EXTCLK)
372 
373 #endif /* __PMAC_ZILOG_H__ */
374