MacIIROMDiskDriver/rdisk.c
2020-07-16 02:27:38 -04:00

286 lines
9.1 KiB
C

#include <Memory.h>
#include <Devices.h>
#include <Files.h>
#include <Disks.h>
#include <Errors.h>
#include <Events.h>
#include <OSUtils.h>
#include "rdisk.h"
// Decode keyboard/PRAM settings
static void RDiskDecodeSettings(RDiskStorage_t *c, Ptr unmount, Ptr mount, Ptr ram) {
// Decode settings
if (RDiskIsRPressed()) { // R boots from ROM disk
*unmount = 0; // Don't unmount so we boot from this drive
*mount = 0; // No need to mount later since we are boot disk
*ram = RDiskIsAPressed(); // A enables RAM disk
} else {
// Read PRAM
char legacy_startup, legacy_ram;
RDiskReadXPRAM(1, 4, &legacy_startup);
RDiskReadXPRAM(1, 5, &legacy_ram);
if (legacy_startup & 1) { // Boot from ROM disk
*unmount = 0; // Don't unmount so we boot from this drive
*mount = 0; // No need to mount later since we are boot disk
*ram = legacy_ram & 1;
} else if (legacy_startup & 2) { // Mount ROM disk
*unmount = 1; // Unmount to not boot from our disk
*mount = 1; // Mount in accRun
*ram = legacy_ram & 1;
} else {
*unmount = 1; // Unmount
*mount = 0; // Don't mount again
*ram = 0; // Don't allocate RAM disk
}
}
}
// Switch to 32-bit mode and copy
#pragma parameter RDiskCopy24(__A0, __A1, __D0)
void RDiskCopy24(Ptr sourcePtr, Ptr destPtr, unsigned long byteCount) {
char mode = true32b;
SwapMMUMode(&mode);
BlockMove(sourcePtr, destPtr, byteCount);
SwapMMUMode(&mode);
}
// Figure out the first available drive number >= 5
static int RDiskFindDrvNum() {
DrvQElPtr dq;
int drvNum = 5;
for (dq = (DrvQElPtr)(GetDrvQHdr())->qHead; dq; dq = (DrvQElPtr)dq->qLink) {
if (dq->dQDrive >= drvNum) { drvNum = dq->dQDrive + 1; }
}
return drvNum;
}
#pragma parameter __D0 RDiskOpen(__A0, __A1)
OSErr RDiskOpen(IOParamPtr p, DCtlPtr d) {
int drvNum;
RDiskStorage_t *c;
char legacy_startup, legacy_ram;
// Do nothing if already opened
if (d->dCtlStorage) { return noErr; }
// Do nothing if inhibited
RDiskReadXPRAM(1, 4, &legacy_startup);
RDiskReadXPRAM(1, 5, &legacy_ram);
if ((legacy_startup & 0x07) == 0x04) { return noErr; }
// Allocate storage struct
d->dCtlStorage = NewHandleSysClear(sizeof(RDiskStorage_t));
if (!d->dCtlStorage) { return openErr; }
// Lock our storage struct and get master pointer
HLock(d->dCtlStorage);
c = *(RDiskStorage_t**)d->dCtlStorage;
// Find first available drive number
drvNum = RDiskFindDrvNum();
// Set drive status
//c->status.track = 0;
c->status.writeProt = -1; // nonzero is write protected
c->status.diskInPlace = 8; // 8 is nonejectable disk
c->status.installed = 1; // drive installed
//c->status.sides = 0;
//c->status.qType = 1;
c->status.dQDrive = drvNum;
//c->status.dQFSID = 0;
c->status.dQRefNum = d->dCtlRefNum;
c->status.driveSize = RDiskSize / 512;
//c->status.driveS1 = (RDiskSize / 512) >> 16;
// Decompress icon
#ifdef RDISK_COMPRESS_ICON_ENABLE
char *src = &RDiskIconCompressed[0];
char *dst = &c->icon[0];
UnpackBits(&src, &dst, RDISK_ICON_SIZE);
#endif
// Add drive to drive queue and return
RDiskAddDrive(c->status.dQRefNum, drvNum, (DrvQElPtr)&c->status.qLink);
return noErr;
}
// Init is called at beginning of first prime (read/write) call
static void RDiskInit(IOParamPtr p, DCtlPtr d, RDiskStorage_t *c) {
char unmountEN, mountEN, ramEN;
// Mark init done
c->initialized = 1;
// Decode settings
RDiskDecodeSettings(c, &unmountEN, &mountEN, &ramEN);
// If RAM disk enabled, try to allocate RAM disk buffer if not already
if (ramEN & !c->ramdisk) {
if (*MMU32bit) { // 32-bit mode
unsigned long minBufPtr, newBufPtr;
// Compute if there is enough high memory
minBufPtr = ((unsigned long)*MemTop / 2) + 1024;
newBufPtr = (unsigned long)*BufPtr - RDiskSize;
if (newBufPtr > minBufPtr && (unsigned long)*BufPtr > newBufPtr) {
// Allocate RAM disk buffer by lowering BufPtr
*BufPtr = (Ptr)newBufPtr;
// Set RAM disk buffer pointer.
c->ramdisk = *BufPtr;
// Copy ROM disk image to RAM disk
BlockMove(RDiskBuf, c->ramdisk, RDiskSize);
// Clearing write protect marks RAM disk enabled
c->status.writeProt = 0;
}
} else { // 24-bit mode
// Put RAM disk just past 8MB
c->ramdisk = (Ptr)(8 * 1024 * 1024);
// Copy ROM disk image to RAM disk
copy24(RDiskBuf, c->ramdisk, RDiskSize);
// Clearing write protect marks RAM disk enabled
c->status.writeProt = 0;
//FIXME: what if we don't have enough RAM?
// Will this wrap around and overwrite low memory?
// That's not the worst, since the system would just crash,
// but it would be better to switch to read-only status
}
}
// Unmount if not booting from ROM disk
if (unmountEN) { c->status.diskInPlace = 0; }
// If mount enabled, enable accRun to post disk inserted event later
if (mountEN) {
d->dCtlDelay = 150; // Set accRun delay (150 ticks is 2.5 sec.)
d->dCtlFlags |= dNeedTimeMask; // Enable accRun
}
}
#pragma parameter __D0 RDiskPrime(__A0, __A1)
OSErr RDiskPrime(IOParamPtr p, DCtlPtr d) {
RDiskStorage_t *c;
char cmd;
Ptr disk;
// Return disk offline error if dCtlStorage null
if (!d->dCtlStorage) { return notOpenErr; }
// Dereference dCtlStorage to get pointer to our context
c = *(RDiskStorage_t**)d->dCtlStorage;
// Initialize if this is the first prime call
if (!c->initialized) { RDiskInit(p, d, c); }
// Return disk offline error if virtual disk not inserted
if (!c->status.diskInPlace) { return offLinErr; }
// Get pointer to RAM or ROM disk buffer
disk = (c->ramdisk ? c->ramdisk : RDiskBuf) + d->dCtlPosition;
// Bounds checking
if (d->dCtlPosition >= RDiskSize || p->ioReqCount >= RDiskSize ||
d->dCtlPosition + p->ioReqCount >= RDiskSize) { return paramErr; }
// Service read or write request
cmd = p->ioTrap & 0x00FF;
if (cmd == aRdCmd) { // Read
// Read from disk into buffer.
if (*MMU32bit) { BlockMove(disk, p->ioBuffer, p->ioReqCount); }
else { copy24(disk, StripAddress(p->ioBuffer), p->ioReqCount); }
} else if (cmd == aWrCmd) { // Write
// Fail if write protected or RAM disk buffer not set up
if (c->status.writeProt || !c->ramdisk) { return wPrErr; }
// Write from buffer into disk.
if (*MMU32bit) { BlockMove(p->ioBuffer, disk, p->ioReqCount); }
else { copy24(StripAddress(p->ioBuffer), disk, p->ioReqCount); }
} else { return noErr; } //FIXME: Fail if cmd isn't read or write?
// Update count and position/offset, then return
d->dCtlPosition += p->ioReqCount;
p->ioActCount = p->ioReqCount;
return noErr;
}
#pragma parameter __D0 RDiskControl(__A0, __A1)
OSErr RDiskControl(CntrlParamPtr p, DCtlPtr d) {
RDiskStorage_t *c;
// Fail if dCtlStorage null
if (!d->dCtlStorage) { return notOpenErr; }
// Dereference dCtlStorage to get pointer to our context
c = *(RDiskStorage_t**)d->dCtlStorage;
// Handle control request based on csCode
switch (p->csCode) {
case killCode:
return noErr;
case kFormat:
if (!c->status.diskInPlace || c->status.writeProt ||
!c->ramdisk) { return controlErr; }
long zero[32];
for (int i = 0; i < 32; i++) { zero[i] = 0; }
for (int i = 0; i < 32; i++) {
copy24((Ptr)zero, c->ramdisk + i * sizeof(zero), sizeof(zero));
}
return noErr;
case kVerify:
if (!c->status.diskInPlace) { return controlErr; }
return noErr;
case kEject:
// "Reinsert" disk if ejected illegally
if (c->status.diskInPlace) {
PostEvent(diskEvt, c->status.dQDrive);
}
return controlErr; // Eject not allowed so return error
case accRun:
d->dCtlFlags &= ~dNeedTimeMask; // Disable accRun
c->status.diskInPlace = 8; // 8 is nonejectable disk
PostEvent(diskEvt, c->status.dQDrive); // Post disk inserted event
return noErr;
case kDriveIcon: case kMediaIcon: // Get icon
#ifdef RDISK_COMPRESS_ICON_ENABLE
*(Ptr*)p->csParam = (Ptr)c->icon;
#else
*(Ptr*)p->csParam = (Ptr)RDiskIcon;
#endif
return noErr;
case kDriveInfo:
// high word (bytes 2 & 3) clear
// byte 1 = primary + fixed media + internal
// byte 0 = drive type (0x10 is RAM disk) / (0x11 is ROM disk)
if (c->status.writeProt) { *(long*)p->csParam = 0x00000410; }
else { *(long*)p->csParam = 0x00000411; }
return noErr;
case 24: // Return SCSI partition size
*(long*)p->csParam = RDiskSize / 512;
return noErr;
case 2351: // Post-boot
c->initialized = 1; // Skip initialization
d->dCtlDelay = 30; // Set accRun delay (30 ticks is 0.5 sec.)
d->dCtlFlags |= dNeedTimeMask; // Enable accRun
return noErr;
default: return controlErr;
}
}
#pragma parameter __D0 RDiskStatus(__A0, __A1)
OSErr RDiskStatus(CntrlParamPtr p, DCtlPtr d) {
RDiskStorage_t *c;
// Fail if dCtlStorage null
if (!d->dCtlStorage) { return notOpenErr; }
// Dereference dCtlStorage to get pointer to our context
c = *(RDiskStorage_t**)d->dCtlStorage;
// Handle status request based on csCode
switch (p->csCode) {
case kDriveStatus:
BlockMove(*d->dCtlStorage, &p->csParam, sizeof(DrvSts2));
return noErr;
default: return statusErr;
}
}
#pragma parameter __D0 RDiskClose(__A0, __A1)
OSErr RDiskClose(IOParamPtr p, DCtlPtr d) {
// If dCtlStorage not null, dispose of it
if (!d->dCtlStorage) { return noErr; }
RDiskStorage_t *c = *(RDiskStorage_t**)d->dCtlStorage;
HUnlock(d->dCtlStorage);
DisposeHandle(d->dCtlStorage);
d->dCtlStorage = NULL;
return noErr;
}