From d876534e6337748372cc55c2beb130c06a86e241 Mon Sep 17 00:00:00 2001
From: RichardG867 <richardg867@gmail.com>
Date: Wed, 14 Oct 2020 16:33:30 -0300
Subject: [PATCH] Proper masking of VIA IDE registers

---
 src/chipset/via_pipc.c | 37 ++++++++++++++++++++++++++++++++-----
 1 file changed, 32 insertions(+), 5 deletions(-)

diff --git a/src/chipset/via_pipc.c b/src/chipset/via_pipc.c
index 377f26147..34f01cf2c 100644
--- a/src/chipset/via_pipc.c
+++ b/src/chipset/via_pipc.c
@@ -170,8 +170,8 @@ pipc_reset_hard(void *priv)
 	dev->ide_regs[0x34] = 0xc0;
     dev->ide_regs[0x3c] = 0x0e;
 
-    if (dev->local < VIA_PIPC_686A)
-	dev->ide_regs[0x40] = 0x08;
+    if (dev->local <= VIA_PIPC_586B)
+	dev->ide_regs[0x40] = 0x04;
     dev->ide_regs[0x41] = 0x02;
     dev->ide_regs[0x42] = 0x09;
     dev->ide_regs[0x43] = (dev->local >= VIA_PIPC_686A) ? 0x0a : 0x3a;
@@ -426,7 +426,7 @@ pipc_read(int func, int addr, void *priv)
     else if ((func <= (pm_func + 2)) && !(dev->pci_isa_regs[0x85] & ((func == (pm_func + 1)) ? 0x04 : 0x08))) /* AC97 / MC97 */
 	ret = dev->ac97_regs[func - pm_func - 1][addr];
 
-    pipc_log("PIPC: read(%d, %02X) = %02X\n", func, addr, ret);
+    if (func == 1) pipc_log("PIPC: read(%d, %02X) = %02X\n", func, addr, ret);
 
     return ret;
 }
@@ -461,7 +461,7 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
     if (func > dev->max_func)
 	return;
 
-    pipc_log("PIPC: write(%d, %02X, %02X)\n", func, addr, val);
+    if (func == 1) pipc_log("PIPC: write(%d, %02X, %02X)\n", func, addr, val);
 
     if (func == 0) { /* PCI-ISA bridge */
 	/* Read-only addresses */
@@ -656,10 +656,37 @@ pipc_write(int func, int addr, uint8_t val, void *priv)
 			break;
 
 		case 0x40:
-			dev->ide_regs[0x40] = val;
+			if (dev->local <= VIA_PIPC_586B) {
+				dev->ide_regs[0x40] = val & 0x03;
+				dev->ide_regs[0x40] |= 0x04;
+			} else
+				dev->ide_regs[0x40] = val & 0x0f;
 			pipc_ide_handlers(dev);
 			break;
 
+		case 0x50: case 0x52:
+			if (dev->local <= VIA_PIPC_586B)
+				dev->ide_regs[addr] = val & 0xe3;
+			else if (dev->local <= VIA_PIPC_596B)
+				dev->ide_regs[addr] = val & 0xeb;
+			else if (dev->local <= VIA_PIPC_686A)
+				dev->ide_regs[addr] = val & 0xef;
+			else
+				dev->ide_regs[addr] = val & 0xf7;
+			break;
+		case 0x51: case 0x53:
+			if (dev->local <= VIA_PIPC_596B)
+				dev->ide_regs[addr] = val & 0xe3;
+			else if (dev->local <= VIA_PIPC_686A)
+				dev->ide_regs[addr] = val & 0xe7;
+			else
+				dev->ide_regs[addr] = val & 0xf7;
+			break;
+
+		case 0x61: case 0x69:
+			dev->ide_regs[addr] = val & 0x0f;
+			break;
+
 		default:
 			dev->ide_regs[addr] = val;
 			break;