In the boot blocks, stop assuming we have a 1:1 mapping of low physical

memory, but instead gather memory layout information and work with the MMU
(or the PROM) to make sure we can actually load the kernel image in a proper
contiguous physical memory area.

In order to do this, we look at the kernel image twice; during the first pass,
the kernel footprint is computed, and then after making sure it can be
loaded, the second pass loads the actual image.

Since such a logic doesn't work on media which can not seek backwards, such
as tapes, we check for the boot device being a tape and, in that case, assume
a fixed (generous) image size and don't load the kernel symbol table (to
avoid seeking backwards); since tape boot is supposed to be only used to
boot bsd.rd, this is something we can live with.

While there, lower the address the boot blocks are loaded in memory, because
the last crank did not work with some early sun4c OpenPROM, which only
map about 3.5MB of memory.

Memory games logic from NetBSD, tape handling by me.

1 files changed, 175 insertions, 0 deletions

diff --git a/sys/arch/sparc/stand/common/mmu.c b/sys/arch/sparc/stand/common/mmu.c
new file mode 100644
index 00000000000..9a554bd11f3
--- /dev/null
+++ b/sys/arch/sparc/stand/common/mmu.c
@@ -0,0 +1,175 @@
+/*	$OpenBSD: mmu.c,v 1.1 2010/06/29 21:33:54 miod Exp $	*/
+/*	$NetBSD: mmu.c,v 1.8 2008/04/28 20:23:36 martin Exp $	*/
+
+/*-
+ * Copyright (c) 2003 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Paul Kranenburg.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <lib/libsa/stand.h>
+#include <machine/ctlreg.h>
+#include <machine/idprom.h>
+#include <machine/pte.h>
+#include <sparc/sparc/asm.h>
+#include <sparc/stand/common/promdev.h>
+
+static int sun4_mmu3l;	/* sun4 3-lvl MMU */
+static int rcookie;	/* sun4 3-lvl MMU region resource */
+static int scookie;	/* sun4/sun4c MMU segment resource */
+static int obmem;	/* SRMMU on-board memory space */
+
+static int pmap_map4(vaddr_t va, paddr_t pa, psize_t size);
+static int pmap_extract4(vaddr_t va, paddr_t *ppa);
+static int pmap_map_srmmu(vaddr_t va, paddr_t pa, psize_t size);
+static int pmap_extract_srmmu(vaddr_t va, paddr_t *ppa);
+
+int (*pmap_map)(vaddr_t va, paddr_t pa, psize_t size);
+int (*pmap_extract)(vaddr_t va, paddr_t *ppa);
+
+int
+mmu_init(void)
+{
+	if (CPU_ISSUN4 || CPU_ISSUN4C) {
+		pmap_map = pmap_map4;
+		pmap_extract = pmap_extract4;
+		if (CPU_ISSUN4) {
+			/* Find out if we're on a 3-lvl sun4 MMU. */
+			struct idprom *idp = prom_getidprom();
+			if (idp->id_machine == ID_SUN4_400)
+				sun4_mmu3l = 1;
+		}
+		/*
+		 * XXX - we just guess which MMU cookies are free:
+		 *	 region 0 maps [0-16MB]
+		 *	 segment 0-16 map [0-4MB]
+		 *	 the PROM mappings use high-valued cookies.
+		 */
+		rcookie = 2;
+		scookie = 17;
+	} else if (CPU_ISSUN4M || CPU_ISSUN4D) {
+		char buf[32];
+		pmap_map = pmap_map_srmmu;
+		pmap_extract = pmap_extract_srmmu;
+		snprintf(buf, sizeof buf, "obmem %lx L!", (u_long)&obmem);
+		prom_interpret(buf);
+	} else
+		return (ENOTSUP);
+
+	return (0);
+}
+
+
+/*
+ * SUN4 & SUN4C VM routines.
+ * Limited functionality wrt. MMU resource management.
+ */
+
+#define getpte4(va)		lda(va, ASI_PTE)
+#define setpte4(va, pte)	sta(va, ASI_PTE, pte)
+
+int
+pmap_map4(vaddr_t va, paddr_t pa, psize_t size)
+{
+	u_int n = (size + NBPG - 1) >> PGSHIFT;
+	u_int pte;
+
+	if (sun4_mmu3l)
+		setregmap((va & -NBPRG), rcookie++);
+
+#ifdef DEBUG
+	printf("Mapping %lx -> %lx (%d pages)\n", va, pa, n);
+#endif
+	setsegmap((va & -NBPSG), ++scookie);
+	while (n--) {
+		pte = PG_S | PG_V | PG_W | PG_NC | ((pa >> PGSHIFT) & PG_PFNUM);
+		setpte4(va, pte);
+		va += NBPG;
+		pa += NBPG;
+		if ((va & (NBPSG - 1)) == 0) {
+#ifdef DEBUG
+	printf("%d ", scookie);
+#endif
+			setsegmap(va, ++scookie);
+		}
+	}
+#ifdef DEBUG
+	printf("\n");
+#endif
+	return (0);
+}
+
+int
+pmap_extract4(vaddr_t va, paddr_t *ppa)
+{
+	u_int pte;
+
+	va &= -NBPG;
+	pte = getpte4(va);
+	if ((pte & PG_V) == 0)
+		return (EFAULT);
+
+	*ppa = (pte & PG_PFNUM) << PGSHIFT;
+	return (0);
+}
+
+
+/*
+ * SRMMU VM routines.
+ * We use the PROM's Forth services to do all the hard work.
+ */
+int
+pmap_map_srmmu(vaddr_t va, paddr_t pa, psize_t size)
+{
+	char buf[64];
+
+	snprintf(buf, sizeof buf, "%lx %x %lx %lx map-pages",
+	    pa, obmem, va, size);
+
+#ifdef DEBUG
+	printf("Mapping kernel: %s\n", buf);
+#endif
+
+	prom_interpret(buf);
+	return (0);
+}
+
+int
+pmap_extract_srmmu(vaddr_t va, paddr_t *ppa)
+{
+	char buf[32];
+	u_int pte;
+
+	va &= -NBPG;
+	snprintf(buf, sizeof buf, "%lx pgmap@ %lx L!", va, (u_long)&pte);
+	prom_interpret(buf);
+	if ((pte & SRMMU_TETYPE) != SRMMU_TEPTE)
+		return (EFAULT);
+
+	*ppa = (pte & SRMMU_PPNMASK) << SRMMU_PPNPASHIFT;
+	return (0);
+}