From 91070cb7388dc5a7f0460ba8043eb056b5883f3b Mon Sep 17 00:00:00 2001
From: sorgelig <pour.garbage@gmail.com>
Date: Fri, 2 Oct 2020 22:36:02 +0800
Subject: [PATCH] ao486: support for mounting HDD and FDD images.

---
 support/x86/x86_ide.cpp | 51 +++++++++++++++++++++++++++--------------
 1 file changed, 34 insertions(+), 17 deletions(-)

diff --git a/support/x86/x86_ide.cpp b/support/x86/x86_ide.cpp
index 5c95eb7..b990ba6 100644
--- a/support/x86/x86_ide.cpp
+++ b/support/x86/x86_ide.cpp
@@ -427,10 +427,15 @@ static void prep_write(ide_config *ide)
 
 	if (ide->state == IDE_STATE_INIT_RW)
 	{
-		uint32_t lba = ide->regs.sector | (ide->regs.cylinder << 8) | (ide->regs.head << 24);
-		//printf("Write to LBA: %d\n", lba);
-		ide->null = !FileSeekLBA(ide->drive[ide->regs.drv].f, lba);
 		ide->regs.status &= ~ATA_STATUS_IRQ;
+		ide->null = 1;
+
+		if (ide->regs.cmd != 0xFA)
+		{
+			uint32_t lba = ide->regs.sector | (ide->regs.cylinder << 8) | (ide->regs.head << 24);
+			//printf("Write to LBA: %d\n", lba);
+			ide->null = !FileSeekLBA(ide->drive[ide->regs.drv].f, lba);
+		}
 	}
 
 	ide->state = IDE_STATE_WAIT_WR;
@@ -441,24 +446,29 @@ static void prep_write(ide_config *ide)
 static void process_write(ide_config *ide)
 {
 	ide_recv_data(ide_buf, ide->prepcnt * 128);
-	if (!ide->null) ide->null = (FileWriteAdv(ide->drive[ide->regs.drv].f, ide_buf, ide->prepcnt * 512, -1) <= 0);
-
-	uint32_t lba = ide->regs.sector | (ide->regs.cylinder << 8) | (ide->regs.head << 24);
-	lba += ide->prepcnt;
-	ide->regs.sector_count -= ide->prepcnt;
-
-	ide->regs.sector = lba;
-	lba >>= 8;
-	ide->regs.cylinder = lba;
-	lba >>= 16;
-	ide->regs.head = lba & 0xF;
-
 	if (ide->regs.cmd == 0xFA)
 	{
 		ide->regs.sector_count = 0;
 		char* filename = user_io_make_filepath(HomeDir(), (char*)ide_buf);
-		printf("Request for new image for drive %d: %s\n", ide->drive[ide->regs.drv].drvnum, filename);
-		x86_set_image(ide->drive[ide->regs.drv].drvnum + 2, filename);
+		int drvnum = (ide->regs.head == 1) ? 0 : (ide->regs.head == 2) ? 1 : (ide->drive[ide->regs.drv].drvnum + 2);
+
+		static const char* names[6] = { "fdd0", "fdd1", "ide00", "ide01", "ide10", "ide11" };
+		printf("Request for new image for drive %s: %s\n", names[drvnum], filename);
+		x86_set_image(drvnum, filename);
+	}
+	else
+	{
+		if (!ide->null) ide->null = (FileWriteAdv(ide->drive[ide->regs.drv].f, ide_buf, ide->prepcnt * 512, -1) <= 0);
+
+		uint32_t lba = ide->regs.sector | (ide->regs.cylinder << 8) | (ide->regs.head << 24);
+		lba += ide->prepcnt;
+		ide->regs.sector_count -= ide->prepcnt;
+
+		ide->regs.sector = lba;
+		lba >>= 8;
+		ide->regs.cylinder = lba;
+		lba >>= 16;
+		ide->regs.head = lba & 0xF;
 	}
 }
 
@@ -511,6 +521,13 @@ static int handle_hdd(ide_config *ide)
 	}
 	break;
 
+	case 0xFA: // mount image
+	{
+		ide->state = IDE_STATE_INIT_RW;
+		prep_write(ide);
+	}
+	break;
+
 	case 0xC6: // set multople
 	{
 		if (!ide->regs.sector_count || ide->regs.sector_count > ide_io_max_size)