[src/trunk]: src/sys/arch/dreamcast/dev/g2 Basic G2 locking implemented.

[marcus <marcus%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/bb6fe5d286c2
branches:  trunk
changeset: 503121:bb6fe5d286c2
user:      marcus <marcus%NetBSD.org@localhost>
date:      Wed Jan 31 21:58:37 2001 +0000

description:
Basic G2 locking implemented.

diffstat:

 sys/arch/dreamcast/dev/g2/g2bus_bus_mem.c |  46 ++++++++++++++++++++++++++++--
 1 files changed, 42 insertions(+), 4 deletions(-)

diffs (116 lines):

diff -r 8f6ca032ebd0 -r bb6fe5d286c2 sys/arch/dreamcast/dev/g2/g2bus_bus_mem.c
--- a/sys/arch/dreamcast/dev/g2/g2bus_bus_mem.c Wed Jan 31 20:58:31 2001 +0000
+++ b/sys/arch/dreamcast/dev/g2/g2bus_bus_mem.c Wed Jan 31 21:58:37 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: g2bus_bus_mem.c,v 1.1 2001/01/31 18:33:24 thorpej Exp $        */
+/*     $NetBSD: g2bus_bus_mem.c,v 1.2 2001/01/31 21:58:37 marcus Exp $ */
 
 /*-
  * Copyright (c) 2001 The NetBSD Foundation, Inc.
@@ -53,8 +53,7 @@
 
 #include <machine/cpu.h> 
 #include <machine/bus.h>
-
-#include <dev/pci/pcivar.h>
+#include <machine/cpufunc.h>
 
 #include <dreamcast/dev/g2/g2busvar.h>
 
@@ -112,16 +111,35 @@
 }
 
 /*
- * XXX NEED TO ADD THE LOCKING STUFF THAT MARCUS MENTIONED!
+ * G2 bus cycles must not be interrupted by IRQs or G2 DMA.
+ * The following paired macros will take the necessary precautions.
  */
 
+#define G2_LOCK                                                                \
+       do {                                                            \
+               disable_intr();                                         \
+               /* suspend any G2 DMA here... */                        \
+               while((*(volatile unsigned int *)0xa05f688c) & 32);     \
+       } while(0)
+
+#define G2_UNLOCK                                                      \
+       do {                                                            \
+               /* resume any G2 DMA here... */                         \
+               enable_intr();                                          \
+       } while(0)
+
+
 u_int8_t
 g2bus_bus_mem_read_1(void *v, bus_space_handle_t sh, bus_size_t off)
 {
        u_int8_t rv;
 
+       G2_LOCK;
+
        rv = *(u_int8_t *)(sh + off);
 
+       G2_UNLOCK;
+
        return (rv);
 }
 
@@ -130,8 +148,12 @@
 {
        u_int16_t rv;
 
+       G2_LOCK;
+
        rv = *(u_int16_t *)(sh + off);
 
+       G2_UNLOCK;
+
        return (rv);
 }
 
@@ -140,8 +162,12 @@
 {
        u_int32_t rv;
 
+       G2_LOCK;
+
        rv = *(u_int32_t *)(sh + off);
 
+       G2_UNLOCK;
+
        return (rv);
 }
 
@@ -150,7 +176,11 @@
     u_int8_t val)
 {
 
+       G2_LOCK;
+
        *(u_int8_t *)(sh + off) = val;
+
+       G2_UNLOCK;
 }
 
 void
@@ -158,7 +188,11 @@
     u_int16_t val)
 {
 
+       G2_LOCK;
+
        *(u_int16_t *)(sh + off) = val;
+
+       G2_UNLOCK;
 }
 
 void
@@ -166,5 +200,9 @@
     u_int32_t val)
 {
 
+       G2_LOCK;
+
        *(u_int32_t *)(sh + off) = val;
+
+       G2_UNLOCK;
 }