From 8d3a7583de295444c05d90e1a75fe3b82aec3888 Mon Sep 17 00:00:00 2001
From: OBattler <oubattler@gmail.com>
Date: Fri, 20 Aug 2021 16:50:39 +0200
Subject: [PATCH] IDE BusMaster IRQ status is no longer automatically cleared
 on IRQ lower.

---
 src/disk/hdc_ide_sff8038i.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/disk/hdc_ide_sff8038i.c b/src/disk/hdc_ide_sff8038i.c
index 97a77388c..733868cc3 100644
--- a/src/disk/hdc_ide_sff8038i.c
+++ b/src/disk/hdc_ide_sff8038i.c
@@ -370,8 +370,10 @@ void
 sff_bus_master_set_irq(int channel, void *priv)
 {
     sff8038i_t *dev = (sff8038i_t *) priv;
-    dev->status &= ~4;
-    dev->status |= (channel >> 4);
+    if (!(dev->status & 0x04) || (channel & 0x40)) {
+	dev->status &= ~4;
+	dev->status |= (channel >> 4);
+    }
 
     channel &= 0x01;
     if (dev->status & 0x04) {