From 21851c06da14b6f2baa79c817c9e77cdaa56872e Mon Sep 17 00:00:00 2001
From: Toni Wilen <twilen@winuae.net>
Date: Sun, 16 Aug 2015 20:12:40 +0300
Subject: [PATCH] x86 bridgeboard disk density emulation.

---
 disk.cpp       | 13 +++++++++++++
 include/disk.h |  6 ++++++
 x86.cpp        | 23 +++++++++++++++++++++--
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/disk.cpp b/disk.cpp
index e22d74e3..a0fa597f 100644
--- a/disk.cpp
+++ b/disk.cpp
@@ -4712,6 +4712,19 @@ bool disk_reserved_getinfo(int num, struct floppy_reserved *fr)
 		fr->secs = drv->num_secs;
 		fr->heads = 2;
 		fr->disk_changed = drv->dskchange || fr->img == NULL;
+		if (currprefs.floppyslots[i].dfxtype == DRV_PC_ONLY_80) {
+			if (fr->cyls < 80) {
+				// 360k in 80 track drive
+				fr->rate = FLOPPY_RATE_300K;
+			} else {
+				if (drv->num_secs > 14)
+					fr->rate = FLOPPY_RATE_500K; // 1.4M
+				else
+					fr->rate = FLOPPY_RATE_250K; // 720K
+			}
+		} else {
+			fr->rate = FLOPPY_RATE_300K;
+		}
 		return true;
 	}
 	return false;
diff --git a/include/disk.h b/include/disk.h
index 27111d2e..b4c724a2 100644
--- a/include/disk.h
+++ b/include/disk.h
@@ -27,6 +27,11 @@ struct diskinfo
 	TCHAR diskname[110];
 };
 
+#define FLOPPY_RATE_500K 0
+#define FLOPPY_RATE_300K 1
+#define FLOPPY_RATE_250K 2
+#define FLOPPY_RATE_1M 3
+
 struct floppy_reserved
 {
 	int num;
@@ -38,6 +43,7 @@ struct floppy_reserved
 	int secs;
 	int drive_cyls;
 	bool disk_changed;
+	int rate;
 };
 void disk_reserved_setinfo(int num, int cyl, int head, int motor);
 bool disk_reserved_getinfo(int num, struct floppy_reserved *fr);
diff --git a/x86.cpp b/x86.cpp
index 27734839..d9e7d25b 100644
--- a/x86.cpp
+++ b/x86.cpp
@@ -909,6 +909,7 @@ static uae_u8 floppy_seekcyl[4];
 static int floppy_delay_hsync;
 static bool floppy_did_reset;
 static bool floppy_irq;
+static uae_u8 floppy_rate;
 
 #define PC_SEEK_DELAY 50
 
@@ -920,6 +921,13 @@ static void floppy_reset(void)
 	floppy_did_reset = true;
 }
 
+static void floppy_hardreset(void)
+{
+	floppy_rate = FLOPPY_RATE_300K;
+	floppy_reset();
+}
+
+
 static void do_floppy_irq2(void)
 {
 	write_log(_T("floppy%d irq (enable=%d)\n"), floppy_num, (floppy_dpc & 8) != 0);
@@ -1026,6 +1034,11 @@ static int floppy_selected(void)
 	return -1;
 }
 
+static bool floppy_valid_rate(struct floppy_reserved *fr)
+{
+	return fr->rate == floppy_rate;
+}
+
 static void floppy_do_cmd(struct x86_bridge *xb)
 {
 	uae_u8 cmd = floppy_cmd[0];
@@ -1175,7 +1188,9 @@ static void floppy_do_cmd(struct x86_bridge *xb)
 			int cyl = pcf->cyl;
 			bool nodata = false;
 			if (valid_floppy) {
-				if (fr.img && pcf->cyl != floppy_cmd[2]) {
+				if (!floppy_valid_rate(&fr)) {
+					nodata = true;
+				} else if (fr.img && pcf->cyl != floppy_cmd[2]) {
 					floppy_status[0] |= 0x40; // abnormal termination
 					floppy_status[2] |= 0x20; // wrong cylinder
 				} else if (fr.img) {
@@ -1240,7 +1255,7 @@ static void floppy_do_cmd(struct x86_bridge *xb)
 
 		case 10:
 		write_log(_T("Floppy read ID\n"));
-		if (!valid_floppy || !fr.img) {
+		if (!valid_floppy || !fr.img || !floppy_valid_rate(&fr)) {
 			floppy_status[0] |= 0x40; // abnormal termination
 			floppy_status[1] |= 0x04; // no data
 		}
@@ -1412,6 +1427,9 @@ static void outfloppy(struct x86_bridge *xb, int portnum, uae_u8 v)
 		case 0x3f7: // configuration control
 		if (xb->type >= TYPE_2286) {
 			write_log(_T("FDC Control Register %02x\n"), v);
+			floppy_rate = v & 3;
+		} else {
+			floppy_rate = FLOPPY_RATE_300K;
 		}
 		break;
 	}
@@ -2837,6 +2855,7 @@ static void bridge_reset(struct x86_bridge *xb)
 	}
 
 	inittiming();
+	floppy_hardreset();
 }
 
 int is_x86_cpu(struct uae_prefs *p)
-- 
2.47.3