1 files changed, 258 insertions, 0 deletions
diff --git a/stand/i386/libi386/biosmem.c b/stand/i386/libi386/biosmem.c
new file mode 100644
index 0000000..7105757
--- /dev/null
+++ b/stand/i386/libi386/biosmem.c
@@ -0,0 +1,258 @@
+/*-
+ * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
+ * All rights reserved.
+ *
+ * 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 AUTHOR 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 AUTHOR 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/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * Obtain memory configuration information from the BIOS
+ */
+#include <stand.h>
+#include <machine/pc/bios.h>
+#include "bootstrap.h"
+#include "libi386.h"
+#include "btxv86.h"
+#include "smbios.h"
+
+vm_offset_t	memtop, memtop_copyin, high_heap_base;
+uint32_t	bios_basemem, bios_extmem, high_heap_size;
+
+static struct bios_smap_xattr smap;
+
+/*
+ * Used to track which method was used to set BIOS memory
+ * regions.
+ */
+static uint8_t b_bios_probed;
+#define	B_BASEMEM_E820	0x1
+#define	B_BASEMEM_12	0x2
+#define	B_EXTMEM_E820	0x4
+#define	B_EXTMEM_E801	0x8
+#define	B_EXTMEM_8800	0x10
+
+/*
+ * The minimum amount of memory to reserve in bios_extmem for the heap.
+ */
+#define	HEAP_MIN	(64 * 1024 * 1024)
+
+/*
+ * Products in this list need quirks to detect
+ * memory correctly. You need both maker and product as
+ * reported by smbios.
+ */
+/* e820 might not return useful extended memory */
+#define	BQ_DISTRUST_E820_EXTMEM	0x1
+struct bios_getmem_quirks {
+	const char *bios_vendor;
+	const char *maker;
+	const char *product;
+	int quirk;
+};
+
+static struct bios_getmem_quirks quirks[] = {
+	{"coreboot", "Acer", "Peppy", BQ_DISTRUST_E820_EXTMEM},
+	{NULL, NULL, NULL, 0}
+};
+
+static int
+bios_getquirks(void)
+{
+	int i;
+
+	for (i = 0; quirks[i].quirk != 0; ++i) {
+		if (smbios_match(quirks[i].bios_vendor, quirks[i].maker,
+		    quirks[i].product))
+			return (quirks[i].quirk);
+	}
+
+	return (0);
+}
+
+void
+bios_getmem(void)
+{
+	uint64_t size;
+
+	/* Parse system memory map */
+	v86.ebx = 0;
+	do {
+		v86.ctl = V86_FLAGS;
+		v86.addr = 0x15;		/* int 0x15 function 0xe820 */
+		v86.eax = 0xe820;
+		v86.ecx = sizeof(struct bios_smap_xattr);
+		v86.edx = SMAP_SIG;
+		v86.es = VTOPSEG(&smap);
+		v86.edi = VTOPOFF(&smap);
+		v86int();
+		if ((V86_CY(v86.efl)) || (v86.eax != SMAP_SIG))
+			break;
+		/* look for a low-memory segment that's large enough */
+		if ((smap.type == SMAP_TYPE_MEMORY) && (smap.base == 0) &&
+		    (smap.length >= (512 * 1024))) {
+			bios_basemem = smap.length;
+			b_bios_probed |= B_BASEMEM_E820;
+		}
+
+		/* look for the first segment in 'extended' memory */
+		if ((smap.type == SMAP_TYPE_MEMORY) &&
+		    (smap.base == 0x100000) &&
+		    !(bios_getquirks() & BQ_DISTRUST_E820_EXTMEM)) {
+			bios_extmem = smap.length;
+			b_bios_probed |= B_EXTMEM_E820;
+		}
+
+		/*
+		 * Look for the highest segment in 'extended' memory beyond
+		 * 1MB but below 4GB.
+		 */
+		if ((smap.type == SMAP_TYPE_MEMORY) &&
+		    (smap.base > 0x100000) &&
+		    (smap.base < 0x100000000ull)) {
+			size = smap.length;
+
+			/*
+			 * If this segment crosses the 4GB boundary,
+			 * truncate it.
+			 */
+			if (smap.base + size > 0x100000000ull)
+				size = 0x100000000ull - smap.base;
+
+			/*
+			 * To make maximum space for the kernel and the modules,
+			 * set heap to use highest HEAP_MIN bytes below 4GB.
+			 */
+			if (high_heap_base < smap.base && size >= HEAP_MIN) {
+				high_heap_base = smap.base + size - HEAP_MIN;
+				high_heap_size = HEAP_MIN;
+			}
+		}
+	} while (v86.ebx != 0);
+
+	/* Fall back to the old compatibility function for base memory */
+	if (bios_basemem == 0) {
+		v86.ctl = 0;
+		v86.addr = 0x12;		/* int 0x12 */
+		v86int();
+
+		bios_basemem = (v86.eax & 0xffff) * 1024;
+		b_bios_probed |= B_BASEMEM_12;
+	}
+
+	/*
+	 * Fall back through several compatibility functions for extended
+	 * memory.
+	 */
+	if (bios_extmem == 0) {
+		v86.ctl = V86_FLAGS;
+		v86.addr = 0x15;		/* int 0x15 function 0xe801 */
+		v86.eax = 0xe801;
+		v86int();
+		if (!(V86_CY(v86.efl))) {
+			/*
+			 * Clear high_heap; it may end up overlapping
+			 * with the segment we're determining here.
+			 * Let the default "steal stuff from top of
+			 * bios_extmem" code below pick up on it.
+			 */
+			high_heap_size = 0;
+			high_heap_base = 0;
+
+			/*
+			 * %cx is the number of 1KiB blocks between 1..16MiB.
+			 * It can only be up to 0x3c00; if it's smaller then
+			 * there's a PC AT memory hole so we can't treat
+			 * it as contiguous.
+			 */
+			bios_extmem = (v86.ecx & 0xffff) * 1024;
+			if (bios_extmem == (1024 * 0x3c00))
+				bios_extmem += (v86.edx & 0xffff) * 64 * 1024;
+
+			/* truncate bios_extmem */
+			if (bios_extmem > 0x3ff00000)
+				bios_extmem = 0x3ff00000;
+
+			b_bios_probed |= B_EXTMEM_E801;
+		}
+	}
+	if (bios_extmem == 0) {
+		v86.ctl = 0;
+		v86.addr = 0x15;		/* int 0x15 function 0x88 */
+		v86.eax = 0x8800;
+		v86int();
+		bios_extmem = (v86.eax & 0xffff) * 1024;
+		b_bios_probed |= B_EXTMEM_8800;
+	}
+
+	/* Set memtop to actual top of memory */
+	if (high_heap_size != 0) {
+		memtop = memtop_copyin = high_heap_base;
+	} else {
+		memtop = memtop_copyin = 0x100000 + bios_extmem;
+	}
+
+	/*
+	 * If we have extended memory and did not find a suitable heap
+	 * region in the SMAP, use the last HEAP_MIN of 'extended' memory as a
+	 * high heap candidate.
+	 */
+	if (bios_extmem >= HEAP_MIN && high_heap_size < HEAP_MIN) {
+		high_heap_size = HEAP_MIN;
+		high_heap_base = memtop - HEAP_MIN;
+		memtop = memtop_copyin = high_heap_base;
+	}
+}
+
+static int
+command_biosmem(int argc, char *argv[])
+{
+	int bq = bios_getquirks();
+
+	printf("bios_basemem: 0x%llx\n", (unsigned long long)bios_basemem);
+	printf("bios_extmem: 0x%llx\n", (unsigned long long)bios_extmem);
+	printf("memtop: 0x%llx\n", (unsigned long long)memtop);
+	printf("high_heap_base: 0x%llx\n", (unsigned long long)high_heap_base);
+	printf("high_heap_size: 0x%llx\n", (unsigned long long)high_heap_size);
+	printf("bios_quirks: 0x%02x", bq);
+	if (bq & BQ_DISTRUST_E820_EXTMEM)
+		printf(" BQ_DISTRUST_E820_EXTMEM");
+	printf("\n");
+	printf("b_bios_probed: 0x%02x", (int)b_bios_probed);
+	if (b_bios_probed & B_BASEMEM_E820)
+		printf(" B_BASEMEM_E820");
+	if (b_bios_probed & B_BASEMEM_12)
+		printf(" B_BASEMEM_12");
+	if (b_bios_probed & B_EXTMEM_E820)
+		printf(" B_EXTMEM_E820");
+	if (b_bios_probed & B_EXTMEM_E801)
+		printf(" B_EXTMEM_E801");
+	if (b_bios_probed & B_EXTMEM_8800)
+		printf(" B_EXTMEM_8800");
+	printf("\n");
+
+	return (CMD_OK);
+}
+
+COMMAND_SET(biosmem, "biosmem", "show BIOS memory setup", command_biosmem);