From c00efe1f293379b5c994b1dcaeded98bb79792fb Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 25 Oct 1994 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1994-10-25

---
 carrera/fns.h     |  2 ++
 carrera/io.h      |  1 +
 carrera/trap.c    | 23 ++++++++++++++++++++++-
 port/devns16552.c |  2 +-
 4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/carrera/fns.h b/carrera/fns.h
index 2ce8eb5a8cc9df5cb1a0628970526fbb5ae7f764..216569fb7a79186f52efbd54c47a837d4709a7e2 100644
--- a/carrera/fns.h
+++ b/carrera/fns.h
@@ -85,6 +85,7 @@ long*		reg(Ureg*, int);
 void		restfpregs(FPsave*, ulong);
 void		screeninit(void);
 void		screenputs(char*, int);
+void		seteisadma(int, void(*)(void));
 long		syscall(Ureg*);
 void		syslog(char*, int);
 void		sysloginit(void);
@@ -141,3 +142,4 @@ Block*	iallocb(int);
 void*	ifroute(ulong);
 ulong	ifunroute(ulong);
 void	parseip(char*, char*);
+void	mpegintr(void);
diff --git a/carrera/io.h b/carrera/io.h
index 8aac77e4a16316cd4598d19329457fc9f90e9b0c..0f3c03a5f424496f5a61fd52208e4fbca6089ca7 100644
--- a/carrera/io.h
+++ b/carrera/io.h
@@ -48,6 +48,7 @@ enum
 	Eisamphys	= 0x91000000,
 	  Eisavgaphys	= Eisamphys+0xA0000,
 	Eisamvirt	= 0xE0300000,	/* Second 1M page entry from Intctl */
+	Eisadmaintr	= 0x40a,
 	Intctlphys	= 0xF0000000,	
 	Intctlvirt	= 0xE0200000,
 	  Uart1int	= (1<<9),
diff --git a/carrera/trap.c b/carrera/trap.c
index dd476e49f9996ae7ec4e6aa47dcac72b69926aa5..f5901e1f096e49c380643a036b85f9a93c561670 100644
--- a/carrera/trap.c
+++ b/carrera/trap.c
@@ -57,6 +57,7 @@ char *fpcause[] =
 };
 char	*fpexcname(Ureg*, ulong, char*);
 #define FPEXPMASK	(0x3f<<12)		/* Floating exception bits in fcr31 */
+void (*eisadma[8])(void);			/* Eisa dma chain vectors */
 
 
 char *regname[]={
@@ -283,9 +284,21 @@ trap(Ureg *ur)
 	}
 }
 
+void
+seteisadma(int ch, void (*func)(void))
+{
+	if(ch < 0 || ch > 7)
+		panic("seteisadma");
+	if(eisadma[ch] != 0)
+		print("EISA dma%d: intr used twice");
+
+	eisadma[ch] = func;
+}
+
 void
 intr(Ureg *ur)
 {
+	int i;
 	static uchar devint;
 	ulong cause = ur->cause;
 	ulong isr, vec;
@@ -351,8 +364,16 @@ intr(Ureg *ur)
 		case 7:
 			audiosbintr();
 			break;
+		case 10:
+			mpegintr();
+			break;
 		case 13:
-			audiodmaintr();
+			isr = EISAINB(Eisadmaintr) & ~(1<<4);
+			for(i = 0; i < 8; i++) {
+				if(isr & 1)
+					eisadma[i]();
+				isr >>= 1;
+			}
 			break;
 		}
 		cause &= ~INTR4;
diff --git a/port/devns16552.c b/port/devns16552.c
index ee67050a107f64509940bf3133fb98cc87d214c0..42f5b573546c5150b0027522f225119ad443031c 100644
--- a/port/devns16552.c
+++ b/port/devns16552.c
@@ -400,7 +400,7 @@ ns16552kick(Uart *p)
 	if(p->cts && p->blocked == 0){
 		n = 0;
 		while((uartrdreg(p, Lstat) & Outready) == 0){
-			if(++n > 10000){
+			if(++n > 100000){
 				print("stuck serial line\n");
 				break;
 			}