From: Alan Cox <alan@linux.intel.com>
Date: Wed, 3 Jan 2018 21:45:32 +0000 (+0000)
Subject: v65c816-big: DMA protection
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=d3ae7d359383f4a745d8621adc0ed3d43867e127;p=FUZIX.git

v65c816-big: DMA protection
---

diff --git a/Kernel/platform-v65c816-big/v65.s b/Kernel/platform-v65c816-big/v65.s
index ca87afa8..6a42b8fe 100644
--- a/Kernel/platform-v65c816-big/v65.s
+++ b/Kernel/platform-v65c816-big/v65.s
@@ -165,6 +165,9 @@ _hd_read_data:
 	sta f:KERNEL_CODE_FAR+hd_rpatch+1	; destination is bank we want
 	phb			; bank will be corrupted
 
+	lda  #$34		; DMA port
+	sta f:$00FE11		; point it at the disk port
+
 	rep #$30
 	.a16
 
@@ -172,9 +175,13 @@ _hd_read_data:
 hd_rpatch:
 	mvn $FF,$FF
 	plb
-	sep #$30
+	sep #$30		; go anywhere
 	.a8
 	.i8
+
+	lda #0
+	sta f:$00FE11		; ensure any DMA window I/O doesn't
+
 	rts
 
 _hd_write_data:
@@ -190,6 +197,9 @@ _hd_write_data:
 	sta f:KERNEL_CODE_FAR+hd_wpatch+2	; source is bank we want
 	phb			; bank will be corrupted
 
+	lda  #$34		; DMA port
+	sta f:$00FE11		; point it at the disk port
+
 	rep #$30
 	.a16
 
@@ -198,9 +208,13 @@ _hd_write_data:
 hd_wpatch:
 	mvn $FF,$FF
 	plb
-	sep #$30
+	sep #$30		; go anywhere
 	.a8
 	.i8
+
+	lda #0
+	sta f:$00FE11		; ensure any DMA window I/O doesn't
+
 	rts
 
 _hd_kmap: