From a0b3e2b11b44dbc1715b7ce91769de444bd32d48 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Fri, 30 Jun 2000 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2000-06-30

---
 pc/memory.c   |  8 ++++----
 pc/sd53c8xx.c | 12 ++++++++++--
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/pc/memory.c b/pc/memory.c
index a33d8f0bed18b5f95d1b14c4c3067180a4996c7e..4f88147dec107a2a7d129e47e75ec88717762a8f 100644
--- a/pc/memory.c
+++ b/pc/memory.c
@@ -171,9 +171,9 @@ mapalloc(RMap* rmap, ulong addr, int size, int align)
 			 */
 			if(maddr > addr)
 				break;
-			if(maddr+mp->size < addr)
+			if(mp->size < addr - maddr)	/* maddr+mp->size < addr, but no overflow */
 				continue;
-			if(addr+size > maddr+mp->size)
+			if(addr - maddr > mp->size - size)	/* addr+size > maddr+mp->size, but no overflow */
 				break;
 			maddr = addr;
 		}
@@ -400,9 +400,9 @@ ramscan(ulong maxmem)
 	if(pa < maxmem)
 		mapfree(&rmapupa, pa, maxmem-pa);
 	if(maxmem < 0xFFE00000)
-		mapfree(&rmapupa, maxmem, 0xFFE00000-maxmem);
+		mapfree(&rmapupa, maxmem, 0x00000000-maxmem);
 	if(MEMDEBUG)
-		print("maxmem %luX %luX\n", maxmem, 0xFFE00000-maxmem);
+		print("maxmem %luX %luX\n", maxmem, 0x00000000-maxmem);
 	*k0 = kzero;
 }
 
diff --git a/pc/sd53c8xx.c b/pc/sd53c8xx.c
index 856f6b8a6e2fe34761cd03c140ca6690e0449c5f..c9a1dc2058761fa2d9a220884f01e95349ee7545 100644
--- a/pc/sd53c8xx.c
+++ b/pc/sd53c8xx.c
@@ -1807,12 +1807,17 @@ cribbios(Controller *c)
 {
 	c->bios.scntl3 = c->n->scntl3;
 	c->bios.stest2 = c->n->stest2;
-	print("sd53c8xx: bios scntl3(%.2x) stest2(%.2x)\n", c->bios.scntl3, c->bios.stest2);
+	KPRINT("sd53c8xx: bios scntl3(%.2x) stest2(%.2x)\n",
+		c->bios.scntl3, c->bios.stest2);
 }
 
 static int
 bios_set_differential(Controller *c)
 {
+	/* rsc: this fails on the 825 */
+	if(strcmp(c->v->name, "NCR53C825") == 0)
+		return 0;
+
 	/* Concept lifted from FreeBSD - thanks Gerard */
 	/* basically, if clock conversion factors are set, then there is
  	 * evidence the bios had a go at the chip, and if so, it would
@@ -1961,8 +1966,11 @@ sympnp(void)
 			ba++;
 		}
 		regpa = upamalloc(regpa & ~0x0F, p->mem[1].size, 0);
-		if(regpa == 0)
+		if(regpa == 0) {
+			print("sd53c8xx: failed to allocate register space (%d bytes at %.8lux)\n",
+				p->mem[1].size, regpa & ~0x0F);
 			continue;
+		}
 
 		script = nil;
 		scriptpa = 0;