/* * 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).