xref: /openbmc/linux/arch/m68k/include/asm/mac_via.h (revision 3a83e4e6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *	6522 Versatile Interface Adapter (VIA)
4  *
5  *	There are two of these on the Mac II. Some IRQ's are vectored
6  *	via them as are assorted bits and bobs - eg rtc, adb. The picture
7  *	is a bit incomplete as the Mac documentation doesn't cover this well
8  */
9 
10 #ifndef _ASM_MAC_VIA_H_
11 #define _ASM_MAC_VIA_H_
12 
13 /*
14  * Base addresses for the VIAs. There are two in every machine,
15  * although on some machines the second is an RBV or an OSS.
16  * The OSS is different enough that it's handled separately.
17  *
18  * Do not use these values directly; use the via1 and via2 variables
19  * instead (and don't forget to check rbv_present when using via2!)
20  */
21 
22 #define VIA1_BASE	(0x50F00000)
23 #define VIA2_BASE	(0x50F02000)
24 #define  RBV_BASE	(0x50F26000)
25 
26 /*
27  *	Not all of these are true post MacII I think.
28  *      CSA: probably the ones CHRP marks as 'unused' change purposes
29  *      when the IWM becomes the SWIM.
30  *      http://www.rs6000.ibm.com/resource/technology/chrpio/via5.mak.html
31  *      ftp://ftp.austin.ibm.com/pub/technology/spec/chrp/inwork/CHRP_IORef_1.0.pdf
32  *
33  * also, http://developer.apple.com/technotes/hw/hw_09.html claims the
34  * following changes for IIfx:
35  * VIA1A_vSccWrReq not available and that VIA1A_vSync has moved to an IOP.
36  * Also, "All of the functionality of VIA2 has been moved to other chips".
37  */
38 
39 #define VIA1A_vSccWrReq	0x80	/* SCC write. (input)
40 				 * [CHRP] SCC WREQ: Reflects the state of the
41 				 * Wait/Request pins from the SCC.
42 				 * [Macintosh Family Hardware]
43 				 * as CHRP on SE/30,II,IIx,IIcx,IIci.
44 				 * on IIfx, "0 means an active request"
45 				 */
46 #define VIA1A_vRev8	0x40	/* Revision 8 board ???
47                                  * [CHRP] En WaitReqB: Lets the WaitReq_L
48 				 * signal from port B of the SCC appear on
49 				 * the PA7 input pin. Output.
50 				 * [Macintosh Family] On the SE/30, this
51 				 * is the bit to flip screen buffers.
52 				 * 0=alternate, 1=main.
53 				 * on II,IIx,IIcx,IIci,IIfx this is a bit
54 				 * for Rev ID. 0=II,IIx, 1=IIcx,IIci,IIfx
55 				 */
56 #define VIA1A_vHeadSel	0x20	/* Head select for IWM.
57 				 * [CHRP] unused.
58 				 * [Macintosh Family] "Floppy disk
59 				 * state-control line SEL" on all but IIfx
60 				 */
61 #define VIA1A_vOverlay	0x10    /* [Macintosh Family] On SE/30,II,IIx,IIcx
62 				 * this bit enables the "Overlay" address
63 				 * map in the address decoders as it is on
64 				 * reset for mapping the ROM over the reset
65 				 * vector. 1=use overlay map.
66 				 * On the IIci,IIfx it is another bit of the
67 				 * CPU ID: 0=normal IIci, 1=IIci with parity
68 				 * feature or IIfx.
69 				 * [CHRP] En WaitReqA: Lets the WaitReq_L
70 				 * signal from port A of the SCC appear
71 				 * on the PA7 input pin (CHRP). Output.
72 				 * [MkLinux] "Drive Select"
73 				 *  (with 0x20 being 'disk head select')
74 				 */
75 #define VIA1A_vSync	0x08    /* [CHRP] Sync Modem: modem clock select:
76                                  * 1: select the external serial clock to
77 				 *    drive the SCC's /RTxCA pin.
78 				 * 0: Select the 3.6864MHz clock to drive
79 				 *    the SCC cell.
80 				 * [Macintosh Family] Correct on all but IIfx
81 				 */
82 
83 /* Macintosh Family Hardware sez: bits 0-2 of VIA1A are volume control
84  * on Macs which had the PWM sound hardware.  Reserved on newer models.
85  * On IIci,IIfx, bits 1-2 are the rest of the CPU ID:
86  * bit 2: 1=IIci, 0=IIfx
87  * bit 1: 1 on both IIci and IIfx.
88  * MkLinux sez bit 0 is 'burnin flag' in this case.
89  * CHRP sez: VIA1A bits 0-2 and 5 are 'unused': if programmed as
90  * inputs, these bits will read 0.
91  */
92 #define VIA1A_vVolume	0x07	/* Audio volume mask for PWM */
93 #define VIA1A_CPUID0	0x02	/* CPU id bit 0 on RBV, others */
94 #define VIA1A_CPUID1	0x04	/* CPU id bit 0 on RBV, others */
95 #define VIA1A_CPUID2	0x10	/* CPU id bit 0 on RBV, others */
96 #define VIA1A_CPUID3	0x40	/* CPU id bit 0 on RBV, others */
97 
98 /* Info on VIA1B is from Macintosh Family Hardware & MkLinux.
99  * CHRP offers no info. */
100 #define VIA1B_vSound	0x80	/* Sound enable (for compatibility with
101 				 * PWM hardware) 0=enabled.
102 				 * Also, on IIci w/parity, shows parity error
103 				 * 0=error, 1=OK. */
104 #define VIA1B_vMystery	0x40    /* On IIci, parity enable. 0=enabled,1=disabled
105 				 * On SE/30, vertical sync interrupt enable.
106 				 * 0=enabled. This vSync interrupt shows up
107 				 * as a slot $E interrupt. */
108 #define VIA1B_vADBS2	0x20	/* ADB state input bit 1 (unused on IIfx) */
109 #define VIA1B_vADBS1	0x10	/* ADB state input bit 0 (unused on IIfx) */
110 #define VIA1B_vADBInt	0x08	/* ADB interrupt 0=interrupt (unused on IIfx)*/
111 #define VIA1B_vRTCEnb	0x04	/* Enable Real time clock. 0=enabled. */
112 #define VIA1B_vRTCClk	0x02    /* Real time clock serial-clock line. */
113 #define VIA1B_vRTCData	0x01    /* Real time clock serial-data line. */
114 
115 /* MkLinux defines the following "VIA1 Register B contents where they
116  * differ from standard VIA1".  From the naming scheme, we assume they
117  * correspond to a VIA work-alike named 'EVR'. */
118 #define	EVRB_XCVR	0x08	/* XCVR_SESSION* */
119 #define	EVRB_FULL	0x10	/* VIA_FULL */
120 #define	EVRB_SYSES	0x20	/* SYS_SESSION */
121 #define	EVRB_AUXIE	0x00	/* Enable A/UX Interrupt Scheme */
122 #define	EVRB_AUXID	0x40	/* Disable A/UX Interrupt Scheme */
123 #define	EVRB_SFTWRIE	0x00	/* Software Interrupt ReQuest */
124 #define	EVRB_SFTWRID	0x80	/* Software Interrupt ReQuest */
125 
126 /*
127  *	VIA2 A register is the interrupt lines raised off the nubus
128  *	slots.
129  *      The below info is from 'Macintosh Family Hardware.'
130  *      MkLinux calls the 'IIci internal video IRQ' below the 'RBV slot 0 irq.'
131  *      It also notes that the slot $9 IRQ is the 'Ethernet IRQ' and
132  *      defines the 'Video IRQ' as 0x40 for the 'EVR' VIA work-alike.
133  *      Perhaps OSS uses vRAM1 and vRAM2 for ADB.
134  */
135 
136 #define VIA2A_vRAM1	0x80	/* RAM size bit 1 (IIci: reserved) */
137 #define VIA2A_vRAM0	0x40	/* RAM size bit 0 (IIci: internal video IRQ) */
138 #define VIA2A_vIRQE	0x20	/* IRQ from slot $E */
139 #define VIA2A_vIRQD	0x10	/* IRQ from slot $D */
140 #define VIA2A_vIRQC	0x08	/* IRQ from slot $C */
141 #define VIA2A_vIRQB	0x04	/* IRQ from slot $B */
142 #define VIA2A_vIRQA	0x02	/* IRQ from slot $A */
143 #define VIA2A_vIRQ9	0x01	/* IRQ from slot $9 */
144 
145 /* RAM size bits decoded as follows:
146  * bit1 bit0  size of ICs in bank A
147  *  0    0    256 kbit
148  *  0    1    1 Mbit
149  *  1    0    4 Mbit
150  *  1    1   16 Mbit
151  */
152 
153 /*
154  *	Register B has the fun stuff in it
155  */
156 
157 #define VIA2B_vVBL	0x80	/* VBL output to VIA1 (60.15Hz) driven by
158 				 * timer T1.
159 				 * on IIci, parity test: 0=test mode.
160 				 * [MkLinux] RBV_PARODD: 1=odd,0=even. */
161 #define VIA2B_vSndJck	0x40	/* External sound jack status.
162 				 * 0=plug is inserted.  On SE/30, always 0 */
163 #define VIA2B_vTfr0	0x20	/* Transfer mode bit 0 ack from NuBus */
164 #define VIA2B_vTfr1	0x10	/* Transfer mode bit 1 ack from NuBus */
165 #define VIA2B_vMode32	0x08	/* 24/32bit switch - doubles as cache flush
166 				 * on II, AMU/PMMU control.
167 				 *   if AMU, 0=24bit to 32bit translation
168 				 *   if PMMU, 1=PMMU is accessing page table.
169 				 * on SE/30 tied low.
170 				 * on IIx,IIcx,IIfx, unused.
171 				 * on IIci/RBV, cache control. 0=flush cache.
172 				 */
173 #define VIA2B_vPower	0x04	/* Power off, 0=shut off power.
174 				 * on SE/30 this signal sent to PDS card. */
175 #define VIA2B_vBusLk	0x02	/* Lock NuBus transactions, 0=locked.
176 				 * on SE/30 sent to PDS card. */
177 #define VIA2B_vCDis	0x01	/* Cache control. On IIci, 1=disable cache card
178 				 * on others, 0=disable processor's instruction
179 				 * and data caches. */
180 
181 /* Apple sez: http://developer.apple.com/technotes/ov/ov_04.html
182  * Another example of a valid function that has no ROM support is the use
183  * of the alternate video page for page-flipping animation. Since there
184  * is no ROM call to flip pages, it is necessary to go play with the
185  * right bit in the VIA chip (6522 Versatile Interface Adapter).
186  * [CSA: don't know which one this is, but it's one of 'em!]
187  */
188 
189 /*
190  *	6522 registers - see databook.
191  * CSA: Assignments for VIA1 confirmed from CHRP spec.
192  */
193 
194 /* partial address decode.  0xYYXX : XX part for RBV, YY part for VIA */
195 /* Note: 15 VIA regs, 8 RBV regs */
196 
197 #define vBufB	0x0000	/* [VIA/RBV]  Register B */
198 #define vBufAH	0x0200  /* [VIA only] Buffer A, with handshake. DON'T USE! */
199 #define vDirB	0x0400  /* [VIA only] Data Direction Register B. */
200 #define vDirA	0x0600  /* [VIA only] Data Direction Register A. */
201 #define vT1CL	0x0800  /* [VIA only] Timer one counter low. */
202 #define vT1CH	0x0a00  /* [VIA only] Timer one counter high. */
203 #define vT1LL	0x0c00  /* [VIA only] Timer one latches low. */
204 #define vT1LH	0x0e00  /* [VIA only] Timer one latches high. */
205 #define vT2CL	0x1000  /* [VIA only] Timer two counter low. */
206 #define vT2CH	0x1200  /* [VIA only] Timer two counter high. */
207 #define vSR	0x1400  /* [VIA only] Shift register. */
208 #define vACR	0x1600  /* [VIA only] Auxiliary control register. */
209 #define vPCR	0x1800  /* [VIA only] Peripheral control register. */
210                         /*            CHRP sez never ever to *write* this.
211 			 *            Mac family says never to *change* this.
212 			 * In fact we need to initialize it once at start. */
213 #define vIFR	0x1a00  /* [VIA/RBV]  Interrupt flag register. */
214 #define vIER	0x1c00  /* [VIA/RBV]  Interrupt enable register. */
215 #define vBufA	0x1e00  /* [VIA/RBV] register A (no handshake) */
216 
217 /* The RBV only decodes the bottom eight address lines; the VIA doesn't
218  * decode the bottom eight -- so vBufB | rBufB will always get you BufB */
219 /* CSA: in fact, only bits 0,1, and 4 seem to be decoded.
220  * BUT note the values for rIER and rIFR, where the top 8 bits *do* seem
221  * to matter.  In fact *all* of the top 8 bits seem to matter;
222  * setting rIER=0x1813 and rIFR=0x1803 doesn't work, either.
223  * Perhaps some sort of 'compatibility mode' is built-in? [21-May-1999]
224  */
225 
226 #define rBufB   0x0000  /* [VIA/RBV]  Register B */
227 #define rExp	0x0001	/* [RBV only] RBV future expansion (always 0) */
228 #define rSIFR	0x0002  /* [RBV only] RBV slot interrupts register. */
229 #define rIFR	0x1a03  /* [VIA/RBV]  RBV interrupt flag register. */
230 #define rMonP   0x0010  /* [RBV only] RBV video monitor type. */
231 #define rChpT   0x0011  /* [RBV only] RBV test mode register (reads as 0). */
232 #define rSIER   0x0012  /* [RBV only] RBV slot interrupt enables. */
233 #define rIER    0x1c13  /* [VIA/RBV]  RBV interrupt flag enable register. */
234 #define rBufA	rSIFR   /* the 'slot interrupts register' is BufA on a VIA */
235 
236 /*
237  * Video monitor parameters, for rMonP:
238  */
239 #define RBV_DEPTH  0x07	/* bits per pixel: 000=1,001=2,010=4,011=8 */
240 #define RBV_MONID  0x38	/* monitor type, as below. */
241 #define RBV_VIDOFF 0x40	/* 1 turns off onboard video */
242 /* Supported monitor types: */
243 #define MON_15BW   (1<<3) /* 15" BW portrait. */
244 #define MON_IIGS   (2<<3) /* 12" color (modified IIGS monitor). */
245 #define MON_15RGB  (5<<3) /* 15" RGB portrait. */
246 #define MON_12OR13 (6<<3) /* 12" BW or 13" RGB. */
247 #define MON_NONE   (7<<3) /* No monitor attached. */
248 
249 /* To clarify IER manipulations */
250 #define IER_SET_BIT(b) (0x80 | (1<<(b)) )
251 #define IER_CLR_BIT(b) (0x7F & (1<<(b)) )
252 
253 #ifndef __ASSEMBLY__
254 
255 extern volatile __u8 *via1,*via2;
256 extern int rbv_present,via_alt_mapping;
257 
258 struct irq_desc;
259 
260 extern void via_l2_flush(int writeback);
261 extern void via_register_interrupts(void);
262 extern void via_irq_enable(int);
263 extern void via_irq_disable(int);
264 extern void via_nubus_irq_startup(int irq);
265 extern void via_nubus_irq_shutdown(int irq);
266 extern void via1_irq(struct irq_desc *desc);
267 extern void via1_set_head(int);
268 extern int via2_scsi_drq_pending(void);
269 
270 static inline int rbv_set_video_bpp(int bpp)
271 {
272 	char val = (bpp==1)?0:(bpp==2)?1:(bpp==4)?2:(bpp==8)?3:-1;
273 	if (!rbv_present || val<0) return -1;
274 	via2[rMonP] = (via2[rMonP] & ~RBV_DEPTH) | val;
275 	return 0;
276 }
277 
278 #endif /* __ASSEMBLY__ */
279 
280 #endif /* _ASM_MAC_VIA_H_ */
281