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/* SPDX-License-Identifier: GPL-2.0 */
/*
* 6522 Versatile Interface Adapter (VIA)
*
* There are two of these on the Mac II. Some IRQ's are vectored
* via them as are assorted bits and bobs - eg rtc, adb. The picture
* is a bit incomplete as the Mac documentation doesn't cover this well
*/
#ifndef _ASM_MAC_VIA_H_
#define _ASM_MAC_VIA_H_
/*
* Base addresses for the VIAs. There are two in every machine,
* although on some machines the second is an RBV or an OSS.
* The OSS is different enough that it's handled separately.
*
* Do not use these values directly; use the via1 and via2 variables
* instead (and don't forget to check rbv_present when using via2!)
*/
#define VIA1_BASE (0x50F00000)
#define VIA2_BASE (0x50F02000)
#define RBV_BASE (0x50F26000)
/*
* Not all of these are true post MacII I think.
* CSA: probably the ones CHRP marks as 'unused' change purposes
* when the IWM becomes the SWIM.
* http://www.rs6000.ibm.com/resource/technology/chrpio/via5.mak.html
* ftp://ftp.austin.ibm.com/pub/technology/spec/chrp/inwork/CHRP_IORef_1.0.pdf
*
* also, http://developer.apple.com/technotes/hw/hw_09.html claims the
* following changes for IIfx:
* VIA1A_vSccWrReq not available and that VIA1A_vSync has moved to an IOP.
* Also, "All of the functionality of VIA2 has been moved to other chips".
*/
#define VIA1A_vSccWrReq 0x80 /* SCC write. (input)
* [CHRP] SCC WREQ: Reflects the state of the
* Wait/Request pins from the SCC.
* [Macintosh Family Hardware]
* as CHRP on SE/30,II,IIx,IIcx,IIci.
* on IIfx, "0 means an active request"
*/
#define VIA1A_vRev8 0x40 /* Revision 8 board ???
* [CHRP] En WaitReqB: Lets the WaitReq_L
* signal from port B of the SCC appear on
* the PA7 input pin. Output.
* [Macintosh Family] On the SE/30, this
* is the bit to flip screen buffers.
* 0=alternate, 1=main.
* on II,IIx,IIcx,IIci,IIfx this is a bit
* for Rev ID. 0=II,IIx, 1=IIcx,IIci,IIfx
*/
#define VIA1A_vHeadSel 0x20 /* Head select for IWM.
* [CHRP] unused.
* [Macintosh Family] "Floppy disk
* state-control line SEL" on all but IIfx
*/
#define VIA1A_vOverlay 0x10 /* [Macintosh Family] On SE/30,II,IIx,IIcx
* this bit enables the "Overlay" address
* map in the address decoders as it is on
* reset for mapping the ROM over the reset
* vector. 1=use overlay map.
* On the IIci,IIfx it is another bit of the
* CPU ID: 0=normal IIci, 1=IIci with parity
* feature or IIfx.
* [CHRP] En WaitReqA: Lets the WaitReq_L
* signal from port A of the SCC appear
* on the PA7 input pin (CHRP). Output.
* [MkLinux] "Drive Select"
* (with 0x20 being 'disk head select')
*/
#define VIA1A_vSync 0x08 /* [CHRP] Sync Modem: modem clock select:
* 1: select the external serial clock to
* drive the SCC's /RTxCA pin.
* 0: Select the 3.6864MHz clock to drive
* the SCC cell.
* [Macintosh Family] Correct on all but IIfx
*/
/* Macintosh Family Hardware sez: bits 0-2 of VIA1A are volume control
* on Macs which had the PWM sound hardware. Reserved on newer models.
* On IIci,IIfx, bits 1-2 are the rest of the CPU ID:
* bit 2: 1=IIci, 0=IIfx
* bit 1: 1 on both IIci and IIfx.
* MkLinux sez bit 0 is 'burnin flag' in this case.
* CHRP sez: VIA1A bits 0-2 and 5 are 'unused': if programmed as
* inputs, these bits will read 0.
*/
#define VIA1A_vVolume 0x07 /* Audio volume mask for PWM */
#define VIA1A_CPUID0 0x02 /* CPU id bit 0 on RBV, others */
#define VIA1A_CPUID1 0x04 /* CPU id bit 0 on RBV, others */
#define VIA1A_CPUID2 0x10 /* CPU id bit 0 on RBV, others */
#define VIA1A_CPUID3 0x40 /* CPU id bit 0 on RBV, others */
/* Info on VIA1B is from Macintosh Family Hardware & MkLinux.
* CHRP offers no info. */
#define VIA1B_vSound 0x80 /* Sound enable (for compatibility with
* PWM hardware) 0=enabled.
* Also, on IIci w/parity, shows parity error
* 0=error, 1=OK. */
#define VIA1B_vMystery 0x40 /* On IIci, parity enable. 0=enabled,1=disabled
* On SE/30, vertical sync interrupt enable.
* 0=enabled. This vSync interrupt shows up
* as a slot $E interrupt. */
#define VIA1B_vADBS2 0x20 /* ADB state input bit 1 (unused on IIfx) */
#define VIA1B_vADBS1 0x10 /* ADB state input bit 0 (unused on IIfx) */
#define VIA1B_vADBInt 0x08 /* ADB interrupt 0=interrupt (unused on IIfx)*/
#define VIA1B_vRTCEnb 0x04 /* Enable Real time clock. 0=enabled. */
#define VIA1B_vRTCClk 0x02 /* Real time clock serial-clock line. */
#define VIA1B_vRTCData 0x01 /* Real time clock serial-data line. */
/* MkLinux defines the following "VIA1 Register B contents where they
* differ from standard VIA1". From the naming scheme, we assume they
* correspond to a VIA work-alike named 'EVR'. */
#define EVRB_XCVR 0x08 /* XCVR_SESSION* */
#define EVRB_FULL 0x10 /* VIA_FULL */
#define EVRB_SYSES 0x20 /* SYS_SESSION */
#define EVRB_AUXIE 0x00 /* Enable A/UX Interrupt Scheme */
#define EVRB_AUXID 0x40 /* Disable A/UX Interrupt Scheme */
#define EVRB_SFTWRIE 0x00 /* Software Interrupt ReQuest */
#define EVRB_SFTWRID 0x80 /* Software Interrupt ReQuest */
/*
* VIA2 A register is the interrupt lines raised off the nubus
* slots.
* The below info is from 'Macintosh Family Hardware.'
* MkLinux calls the 'IIci internal video IRQ' below the 'RBV slot 0 irq.'
* It also notes that the slot $9 IRQ is the 'Ethernet IRQ' and
* defines the 'Video IRQ' as 0x40 for the 'EVR' VIA work-alike.
* Perhaps OSS uses vRAM1 and vRAM2 for ADB.
*/
#define VIA2A_vRAM1 0x80 /* RAM size bit 1 (IIci: reserved) */
#define VIA2A_vRAM0 0x40 /* RAM size bit 0 (IIci: internal video IRQ) */
#define VIA2A_vIRQE 0x20 /* IRQ from slot $E */
#define VIA2A_vIRQD 0x10 /* IRQ from slot $D */
#define VIA2A_vIRQC 0x08 /* IRQ from slot $C */
#define VIA2A_vIRQB 0x04 /* IRQ from slot $B */
#define VIA2A_vIRQA 0x02 /* IRQ from slot $A */
#define VIA2A_vIRQ9 0x01 /* IRQ from slot $9 */
/* RAM size bits decoded as follows:
* bit1 bit0 size of ICs in bank A
* 0 0 256 kbit
* 0 1 1 Mbit
* 1 0 4 Mbit
* 1 1 16 Mbit
*/
/*
* Register B has the fun stuff in it
*/
#define VIA2B_vVBL 0x80 /* VBL output to VIA1 (60.15Hz) driven by
* timer T1.
* on IIci, parity test: 0=test mode.
* [MkLinux] RBV_PARODD: 1=odd,0=even. */
#define VIA2B_vSndJck 0x40 /* External sound jack status.
* 0=plug is inserted. On SE/30, always 0 */
#define VIA2B_vTfr0 0x20 /* Transfer mode bit 0 ack from NuBus */
#define VIA2B_vTfr1 0x10 /* Transfer mode bit 1 ack from NuBus */
#define VIA2B_vMode32 0x08 /* 24/32bit switch - doubles as cache flush
* on II, AMU/PMMU control.
* if AMU, 0=24bit to 32bit translation
* if PMMU, 1=PMMU is accessing page table.
* on SE/30 tied low.
* on IIx,IIcx,IIfx, unused.
* on IIci/RBV, cache control. 0=flush cache.
*/
#define VIA2B_vPower 0x04 /* Power off, 0=shut off power.
* on SE/30 this signal sent to PDS card. */
#define VIA2B_vBusLk 0x02 /* Lock NuBus transactions, 0=locked.
* on SE/30 sent to PDS card. */
#define VIA2B_vCDis 0x01 /* Cache control. On IIci, 1=disable cache card
* on others, 0=disable processor's instruction
* and data caches. */
/* Apple sez: http://developer.apple.com/technotes/ov/ov_04.html
* Another example of a valid function that has no ROM support is the use
* of the alternate video page for page-flipping animation. Since there
* is no ROM call to flip pages, it is necessary to go play with the
* right bit in the VIA chip (6522 Versatile Interface Adapter).
* [CSA: don't know which one this is, but it's one of 'em!]
*/
/*
* 6522 registers - see databook.
* CSA: Assignments for VIA1 confirmed from CHRP spec.
*/
/* partial address decode. 0xYYXX : XX part for RBV, YY part for VIA */
/* Note: 15 VIA regs, 8 RBV regs */
#define vBufB 0x0000 /* [VIA/RBV] Register B */
#define vBufAH 0x0200 /* [VIA only] Buffer A, with handshake. DON'T USE! */
#define vDirB 0x0400 /* [VIA only] Data Direction Register B. */
#define vDirA 0x0600 /* [VIA only] Data Direction Register A. */
#define vT1CL 0x0800 /* [VIA only] Timer one counter low. */
#define vT1CH 0x0a00 /* [VIA only] Timer one counter high. */
#define vT1LL 0x0c00 /* [VIA only] Timer one latches low. */
#define vT1LH 0x0e00 /* [VIA only] Timer one latches high. */
#define vT2CL 0x1000 /* [VIA only] Timer two counter low. */
#define vT2CH 0x1200 /* [VIA only] Timer two counter high. */
#define vSR 0x1400 /* [VIA only] Shift register. */
#define vACR 0x1600 /* [VIA only] Auxiliary control register. */
#define vPCR 0x1800 /* [VIA only] Peripheral control register. */
/* CHRP sez never ever to *write* this.
* Mac family says never to *change* this.
* In fact we need to initialize it once at start. */
#define vIFR 0x1a00 /* [VIA/RBV] Interrupt flag register. */
#define vIER 0x1c00 /* [VIA/RBV] Interrupt enable register. */
#define vBufA 0x1e00 /* [VIA/RBV] register A (no handshake) */
/* The RBV only decodes the bottom eight address lines; the VIA doesn't
* decode the bottom eight -- so vBufB | rBufB will always get you BufB */
/* CSA: in fact, only bits 0,1, and 4 seem to be decoded.
* BUT note the values for rIER and rIFR, where the top 8 bits *do* seem
* to matter. In fact *all* of the top 8 bits seem to matter;
* setting rIER=0x1813 and rIFR=0x1803 doesn't work, either.
* Perhaps some sort of 'compatibility mode' is built-in? [21-May-1999]
*/
#define rBufB 0x0000 /* [VIA/RBV] Register B */
#define rExp 0x0001 /* [RBV only] RBV future expansion (always 0) */
#define rSIFR 0x0002 /* [RBV only] RBV slot interrupts register. */
#define rIFR 0x1a03 /* [VIA/RBV] RBV interrupt flag register. */
#define rMonP 0x0010 /* [RBV only] RBV video monitor type. */
#define rChpT 0x0011 /* [RBV only] RBV test mode register (reads as 0). */
#define rSIER 0x0012 /* [RBV only] RBV slot interrupt enables. */
#define rIER 0x1c13 /* [VIA/RBV] RBV interrupt flag enable register. */
#define rBufA rSIFR /* the 'slot interrupts register' is BufA on a VIA */
/*
* Video monitor parameters, for rMonP:
*/
#define RBV_DEPTH 0x07 /* bits per pixel: 000=1,001=2,010=4,011=8 */
#define RBV_MONID 0x38 /* monitor type, as below. */
#define RBV_VIDOFF 0x40 /* 1 turns off onboard video */
/* Supported monitor types: */
#define MON_15BW (1<<3) /* 15" BW portrait. */
#define MON_IIGS (2<<3) /* 12" color (modified IIGS monitor). */
#define MON_15RGB (5<<3) /* 15" RGB portrait. */
#define MON_12OR13 (6<<3) /* 12" BW or 13" RGB. */
#define MON_NONE (7<<3) /* No monitor attached. */
/* To clarify IER manipulations */
#define IER_SET_BIT(b) (0x80 | (1<<(b)) )
#define IER_CLR_BIT(b) (0x7F & (1<<(b)) )
#ifndef __ASSEMBLY__
extern volatile __u8 *via1,*via2;
extern int rbv_present,via_alt_mapping;
struct irq_desc;
extern void via_l2_flush(int writeback);
extern void via_register_interrupts(void);
extern void via_irq_enable(int);
extern void via_irq_disable(int);
extern void via_nubus_irq_startup(int irq);
extern void via_nubus_irq_shutdown(int irq);
extern void via1_irq(struct irq_desc *desc);
extern void via1_set_head(int);
extern int via2_scsi_drq_pending(void);
static inline int rbv_set_video_bpp(int bpp)
{
char val = (bpp==1)?0:(bpp==2)?1:(bpp==4)?2:(bpp==8)?3:-1;
if (!rbv_present || val<0) return -1;
via2[rMonP] = (via2[rMonP] & ~RBV_DEPTH) | val;
return 0;
}
#endif /* __ASSEMBLY__ */
#endif /* _ASM_MAC_VIA_H_ */
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