Fixed CD-ROM timings on the NCR 53x8xx SCSI controllers, the IDE_TIME, CDROM_TIME, and ZIP_TIME values, and the delay added to the CD-ROM READ SUBCHANNEL command, fixes slowdowns on several games that use CD Audio, such as Tomb Raider II.

src/disk/hdc_ide.c

@@ -9,7 +9,7 @@
  *		Implementation of the IDE emulation for hard disks and ATAPI
  *		CD-ROM devices.
  *
- * Version:	@(#)hdc_ide.c	1.0.64	2019/11/06
+ * Version:	@(#)hdc_ide.c	1.0.65	2019/11/19
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
@@ -109,7 +109,7 @@
 #define FEATURE_DISABLE_IRQ_OVERLAPPED	0xdd
 #define FEATURE_DISABLE_IRQ_SERVICE	0xde
 
-#define IDE_TIME 20.0 / 3.0
+#define IDE_TIME 10.0
 
 
 typedef struct {
@@ -175,70 +175,72 @@ ide_get_drive(int ch)
 double
 ide_get_period(ide_t *ide, int size)
 {
-    double period = 10.0 / 3.0;
+    double period = (10.0 / 3.0);
 
+    /* We assume that 1 MB = 1000000 B in this case, so we have as
+       many B/us as there are MB/s because 1 s = 1000000 us. */
     switch(ide->mdma_mode & 0x300) {
 	case 0x000:	/* PIO */
 		switch(ide->mdma_mode & 0xff) {
 			case 0:
-				period = 10.0 / 3.0;
+				period = (10.0 / 3.0);
 				break;
 			case 1:
-				period = (period * 600.0) / 383.0;
+				period = (20.0 / 3.83);
 				break;
 			case 2:
-				period = 25.0 / 3.0;
+				period = (25.0 / 3.0);
 				break;
 			case 3:
-				period = 100.0 / 9.0;
+				period = (100.0 / 9.0);
 				break;
 			case 4:
-				period = 50.0 / 3.0;
+				period = (50.0 / 3.0);
 				break;
 		}
 		break;
 	case 0x100:	/* Single Word DMA */
 		switch(ide->mdma_mode & 0xff) {
 			case 0:
-				period = 25.0 / 12.0;
+				period = (25.0 / 12.0);
 				break;
 			case 1:
-				period = 25.0 / 6.0;
+				period = (25.0 / 6.0);
 				break;
 			case 2:
-				period = 25.0 / 3.0;
+				period = (25.0 / 3.0);
 				break;
 		}
 		break;
 	case 0x200:	/* Multiword DMA */
 		switch(ide->mdma_mode & 0xff) {
 			case 0:
-				period = 25.0 / 6.0;
+				period = (25.0 / 6.0);
 				break;
 			case 1:
-				period = 40.0 / 3.0;
+				period = (40.0 / 3.0);
 				break;
 			case 2:
-				period = 50.0 / 3.0;
+				period = (50.0 / 3.0);
 				break;
 		}
 		break;
 	case 0x300:	/* Ultra DMA */
 		switch(ide->mdma_mode & 0xff) {
 			case 0:
-				period = 50.0 / 3.0;
+				period = (50.0 / 3.0);
 				break;
 			case 1:
 				period = 25.0;
 				break;
 			case 2:
-				period = 100.0 / 3.0;
+				period = (100.0 / 3.0);
 				break;
 			case 3:
-				period = 400.0 / 9.0;
+				period = (400.0 / 9.0);
 				break;
 			case 4:
-				period = 200.0 / 3.0;
+				period = (200.0 / 3.0);
 				break;
 			case 5:
 				period = 100.0;
@@ -247,9 +249,26 @@ ide_get_period(ide_t *ide, int size)
 		break;
     }
 
-    period *= 1048576.0;			/* period * MB - get bytes per second */
+    period = (10.0 / 3.0);
-    period = ((double) size) / period;		/* size / period to get seconds */
+
-    return period * 1000000.0;			/* return seconds * 1000000 to convert to us */
+    period = (1.0 / period);		/* get us for 1 byte */
+    return period * ((double) size);	/* multiply by bytes to get period for the entire transfer */
+}
+
+
+double
+ide_atapi_get_period(uint8_t channel)
+{
+    ide_t *ide = ide_drives[channel];
+ 
+    ide_log("ide_atapi_get_period(%i)\n", channel);
+
+    if (!ide) {
+	ide_log("Get period failed\n");
+	return -1.0;
+    }
+
+    return ide_get_period(ide, 1);
 }
 
 

src/disk/hdc_ide.h

@@ -9,12 +9,12 @@
  *		Implementation of the IDE emulation for hard disks and ATAPI
  *		CD-ROM devices.
  *
- * Version:	@(#)hdd_ide.h	1.0.15	2018/10/31
+ * Version:	@(#)hdd_ide.h	1.0.16	2019/11/19
  *
  * Authors:	Sarah Walker, <http://pcem-emulator.co.uk/>
  *		Miran Grca, <mgrca8@gmail.com>
- *		Copyright 2008-2018 Sarah Walker.
+ *		Copyright 2008-2019 Sarah Walker.
- *		Copyright 2016-2018 Miran Grca.
+ *		Copyright 2016-2019 Miran Grca.
  */
 #ifndef EMU_IDE_H
 # define EMU_IDE_H
@@ -130,6 +130,7 @@ extern void	ide_pri_disable(void);
 extern void	ide_sec_enable(void);
 extern void	ide_sec_disable(void);
 
+extern double	ide_atapi_get_period(uint8_t channel);
 extern void	ide_set_callback(uint8_t channel, double callback);
 
 extern void	ide_padstr(char *str, const char *src, int len);

src/disk/zip.c

@@ -9,11 +9,11 @@
  *		Implementation of the Iomega ZIP drive with SCSI(-like)
  *		commands, for both ATAPI and SCSI usage.
  *
- * Version:	@(#)zip.c	1.0.37	2018/11/02
+ * Version:	@(#)zip.c	1.0.38	2019/11/19
  *
  * Author:	Miran Grca, <mgrca8@gmail.com>
  *
- *		Copyright 2018 Miran Grca.
+ *		Copyright 2018,2019 Miran Grca.
  */
 #include <stdio.h>
 #include <stdint.h>
@@ -854,6 +854,26 @@ zip_update_request_length(zip_t *dev, int len, int block_len)
 }
 
 
+static double
+zip_bus_speed(zip_t *dev)
+{
+    double ret = -1.0;
+
+    if (dev->drv->bus_type == ZIP_BUS_SCSI) {
+	dev->callback = -1.0;	/* Speed depends on SCSI controller */
+	return 0.0;
+    } else {
+	if (dev && dev->drv)
+		ret = ide_atapi_get_period(dev->drv->ide_channel);
+	if (ret == -1.0) {
+		dev->callback = -1.0;
+		return 0.0;
+	} else
+		return ret * 1000000.0;
+    }
+}
+
+
 static void
 zip_command_common(zip_t *dev)
 {
@@ -868,12 +888,8 @@ zip_command_common(zip_t *dev)
 	if (dev->drv->bus_type == ZIP_BUS_SCSI) {
 		dev->callback = -1.0;	/* Speed depends on SCSI controller */
 		return;
-	} else {
+	} else
-		if (zip_current_mode(dev) == 2)
+		bytes_per_second = zip_bus_speed(dev);
-			bytes_per_second = 66666666.666666666666666;	/* 66 MB/s MDMA-2 speed */
-		else
-			bytes_per_second =  8333333.333333333333333;	/* 8.3 MB/s PIO-2 speed */
-	}
 
 	period = 1000000.0 / bytes_per_second;
 	dev->callback = period * (double) (dev->packet_len);

src/disk/zip.h

@@ -9,11 +9,11 @@
  *		Implementation of the Iomega ZIP drive with SCSI(-like)
  *		commands, for both ATAPI and SCSI usage.
  *
- * Version:	@(#)zip.h	1.0.9	2018/10/31
+ * Version:	@(#)zip.h	1.0.10	2019/11/19
  *
  * Author:	Miran Grca, <mgrca8@gmail.com>
  *
- *		Copyright 2018 Miran Grca.
+ *		Copyright 2018,2019 Miran Grca.
  */
 #ifndef EMU_ZIP_H
 #define EMU_ZIP_H
@@ -23,7 +23,7 @@
 
 #define BUF_SIZE 32768
 
-#define ZIP_TIME	500.0
+#define ZIP_TIME	10.0
 
 #define ZIP_SECTORS (96*2048)
 

src/scsi/scsi_cdrom.c

@@ -9,7 +9,7 @@
  *		Implementation of the CD-ROM drive with SCSI(-like)
  *		commands, for both ATAPI and SCSI usage.
  *
- * Version:	@(#)scsi_cdrom.c	1.0.71	2019/09/26
+ * Version:	@(#)scsi_cdrom.c	1.0.72	2019/11/19
  *
  * Author:	Miran Grca, <mgrca8@gmail.com>
  *
@@ -604,15 +604,19 @@ scsi_cdrom_update_request_length(scsi_cdrom_t *dev, int len, int block_len)
 static double
 scsi_cdrom_bus_speed(scsi_cdrom_t *dev)
 {
+    double ret = -1.0;
+
     if (dev->drv->bus_type == CDROM_BUS_SCSI) {
 	dev->callback = -1.0;	/* Speed depends on SCSI controller */
 	return 0.0;
     } else {
-	/* TODO: Get the actual selected speed from IDE. */
+	if (dev && dev->drv)
-	if (scsi_cdrom_current_mode(dev) == 2)
+		ret = ide_atapi_get_period(dev->drv->ide_channel);
-		return 66666666.666666666666666;	/* 66 MB/s MDMA-2 speed */
+	if (ret == -1.0) {
-	else
+		dev->callback = -1.0;
-		return  8333333.333333333333333;	/* 8.3 MB/s PIO-2 speed */
+		return 0.0;
+	} else
+		return ret * 1000000.0;
     }
 }
 
@@ -663,7 +667,7 @@ scsi_cdrom_command_common(scsi_cdrom_t *dev)
 		case 0xb9:
 		case 0xbe:
 			if (dev->current_cdb[0] == 0x42)
-				dev->callback += 200.0 * CDROM_TIME;
+				dev->callback += 40.0;
 			/* Account for seek time. */
 			bytes_per_second = 176.0 * 1024.0;
 			bytes_per_second *= (double) dev->drv->cur_speed;

src/scsi/scsi_cdrom.h

@@ -9,17 +9,17 @@
  *		Implementation of the CD-ROM drive with SCSI(-like)
  *		commands, for both ATAPI and SCSI usage.
  *
- * Version:	@(#)scsi_cdrom.h	1.0.1	2018/10/17
+ * Version:	@(#)scsi_cdrom.h	1.0.2	2019/11/19
  *
  * Author:	Miran Grca, <mgrca8@gmail.com>
  *
- *		Copyright 2018 Miran Grca.
+ *		Copyright 2018,2019 Miran Grca.
  */
 #ifndef EMU_SCSI_CDROM_H
 #define EMU_SCSI_CDROM_H
 
 
-#define CDROM_TIME	500.0
+#define CDROM_TIME	10.0
 
 
 #ifdef SCSI_DEVICE_H

src/scsi/scsi_ncr53c8xx.c

@@ -13,7 +13,7 @@
  *		To do: Identify the type of serial EEPROM used and its
  *		interface.
  *
- * Version:	@(#)scsi_ncr53c8xx.c	1.0.17	2018/10/30
+ * Version:	@(#)scsi_ncr53c8xx.c	1.0.18	2019/11/19
  *
  * Authors:	Paul Brook (QEMU)
  *		Artyom Tarasenko (QEMU)
@@ -705,10 +705,12 @@ ncr53c8xx_add_msg_byte(ncr53c8xx_t *dev, uint8_t data)
 static void
 ncr53c8xx_timer_on(ncr53c8xx_t *dev, scsi_device_t *sd, double p)
 {
-    if (p <= 0)
+    double period;
-	timer_on_auto(&dev->timer, ((double) sd->buffer_length) * 0.1);	/* Fast SCSI: 10000000 bytes per second */
+
-    else
+    /* Fast SCSI: 10000000 bytes per second */
-	timer_on_auto(&dev->timer, p);
+    period = (p > 0.0) ? p : (((double) sd->buffer_length) * 0.1);
+
+    timer_on_auto(&dev->timer, period + 40.0);
 }
 
 
@@ -1023,11 +1025,12 @@ again:
 	/* If we receive an empty opcode increment the DSP by 4 bytes
 	   instead of 8 and execute the next opcode at that location */
 	dev->dsp += 4;
-	timer_on_auto(&dev->timer, 10.0);
 	if (insn_processed < 100)
 		goto again;
-	else
+	else {
+		timer_on_auto(&dev->timer, 10.0);
 		return;
+	}
     }
     addr = read_dword(dev, dev->dsp + 4);
     ncr53c8xx_log("SCRIPTS dsp=%08x opcode %08x arg %08x\n", dev->dsp, insn, addr);
@@ -1093,8 +1096,6 @@ again:
 				dev->dfifo = dev->dbc & 0xff;
 				dev->ctest5 = (dev->ctest5 & 0xfc) | ((dev->dbc >> 8) & 3);
 
-				timer_on_auto(&dev->timer, 40.0);
-
 				if (dev->dcntl & NCR_DCNTL_SSM)
 					ncr53c8xx_script_dma_interrupt(dev, NCR_DSTAT_SSI);
 				return;
@@ -1363,8 +1364,6 @@ again:
 		ncr53c8xx_log("%02X: Unknown command\n", (uint8_t) (insn >> 30));
     }
 
-    timer_on_auto(&dev->timer, 40.0);
-
     ncr53c8xx_log("instructions processed %i\n", insn_processed);
     if (insn_processed > 10000 && !dev->waiting) {
 	/* Some windows drivers make the device spin waiting for a memory
@@ -1393,6 +1392,8 @@ again:
 		ncr53c8xx_log("NCR 810: SCRIPTS: Waiting\n");
     }
 
+    timer_on_auto(&dev->timer, 40.0);
+
     ncr53c8xx_log("SCRIPTS execution stopped\n");
 }
 
@@ -1419,8 +1420,6 @@ ncr53c8xx_callback(void *p)
 
     if (dev->sstop)
 	timer_stop(&dev->timer);
-    else
-	timer_on_auto(&dev->timer, 10.0);
 }