Replaced memsizes.c with smaller memmap.c, taking advantage of __data16,

and creating a memory map that's easier to work with than the E820 map.

src/arch/i386/firmware/pcbios/memmap.c

@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdint.h>
+#include <errno.h>
+#include <realmode.h>
+#include <bios.h>
+#include <memmap.h>
+
+/**
+ * @file
+ *
+ * Memory mapping
+ *
+ */
+
+/** Magic value for INT 15,e820 calls */
+#define SMAP ( 0x534d4150 )
+
+/** An INT 15,e820 memory map entry */
+struct e820_entry {
+	/** Start of region */
+	uint64_t start;
+	/** Length of region */
+	uint64_t len;
+	/** Type of region */
+	uint32_t type;
+} __attribute__ (( packed ));
+
+#define E820_TYPE_RAM		1 /**< Normal memory */
+#define E820_TYPE_RESERVED	2 /**< Reserved and unavailable */
+#define E820_TYPE_ACPI		3 /**< ACPI reclaim memory */
+#define E820_TYPE_NVS		4 /**< ACPI NVS memory */
+
+/** Buffer for INT 15,e820 calls */
+static struct e820_entry __data16 ( e820buf );
+#define e820buf __use_data16 ( e820buf )
+
+/**
+ * Get size of base memory from BIOS free base memory counter
+ *
+ * @ret basemem		Base memory size, in kB
+ */
+static unsigned int basememsize ( void ) {
+	uint16_t basemem;
+
+	get_real ( basemem, BDA_SEG, 0x0013 );
+	DBG ( "Base memory size %dkB\n", basemem );
+	return basemem;
+}
+
+/**
+ * Get size of extended memory via INT 15,e801
+ *
+ * @ret extmem		Extended memory size, in kB, or 0
+ */
+static unsigned int extmemsize_e801 ( void ) {
+	uint16_t extmem_1m_to_16m_k, extmem_16m_plus_64k;
+	uint16_t confmem_1m_to_16m_k, confmem_16m_plus_64k;
+	unsigned int flags;
+	unsigned int extmem;
+
+	REAL_EXEC ( rm_mem_e801,
+		    "int $0x15\n\t"
+		    "pushfw\n\t"
+		    "popw %w0\n\t",
+		    5,
+		    OUT_CONSTRAINTS ( "=r" ( flags ),
+				      "=a" ( extmem_1m_to_16m_k ),
+				      "=b" ( extmem_16m_plus_64k ),
+				      "=c" ( confmem_1m_to_16m_k ),
+				      "=d" ( confmem_16m_plus_64k ) ),
+		    IN_CONSTRAINTS ( "a" ( 0xe801 ) ),
+		    CLOBBER ( "cc" ) );
+
+	if ( flags & CF )
+		return 0;
+
+	if ( ! ( extmem_1m_to_16m_k | extmem_16m_plus_64k ) ) {
+		extmem_1m_to_16m_k = confmem_1m_to_16m_k;
+		extmem_16m_plus_64k = confmem_16m_plus_64k;
+	}
+
+	extmem = ( extmem_1m_to_16m_k + ( extmem_16m_plus_64k * 64 ) );
+	DBG ( "Extended memory size %d+64*%d=%d kB\n",
+	      extmem_1m_to_16m_k, extmem_16m_plus_64k, extmem );
+	return extmem;
+}
+
+/**
+ * Get size of extended memory via INT 15,88
+ *
+ * @ret extmem		Extended memory size, in kB
+ */
+static unsigned int extmemsize_88 ( void ) {
+	uint16_t extmem;
+
+	REAL_EXEC ( rm_mem_88,
+		    "int $0x15\n\t"
+		    "jnc 1f\n\t"
+		    "xorw %%ax, %%ax\n\t"
+		    "\n1:\n\t",
+		    1,
+		    OUT_CONSTRAINTS ( "=a" ( extmem ) ),
+		    IN_CONSTRAINTS ( "a" ( 0x8800 ) ),
+		    CLOBBER ( "cc" ) );
+
+	DBG ( "Extended memory size %d kB\n", extmem );
+	return extmem;
+}
+
+/**
+ * Get size of extended memory
+ *
+ * @ret extmem		Extended memory size, in kB
+ */
+static unsigned int extmemsize ( void ) {
+	unsigned int extmem;
+
+	/* Try INT 15,e801 first, then fall back to INT 15,88 */
+	extmem = extmemsize_e801();
+	if ( ! extmem )
+		extmem = extmemsize_88();
+	return extmem;
+}
+
+/**
+ * Get e820 memory map
+ *
+ * @v memmap		Memory map to fill in
+ * @v entries		Maximum number of entries in memory map
+ * @ret rc		Return status code
+ */
+static int meme820 ( struct memory_region *memmap, unsigned int entries ) {
+	unsigned int index = 0;
+	uint32_t next = 0;
+	uint32_t smap;
+	unsigned int flags;
+	unsigned int discard_c, discard_d, discard_D;
+
+	do {
+		REAL_EXEC ( rm_mem_e820,
+			    "int $0x15\n\t"
+			    "pushfw\n\t"
+			    "popw %w0\n\t",
+			    6,
+			    OUT_CONSTRAINTS ( "=r" ( flags ),
+					      "=a" ( smap ),
+					      "=b" ( next ),
+					      "=D" ( discard_D ),
+					      "=c" ( discard_c ),
+					      "=d" ( discard_d ) ),
+			    IN_CONSTRAINTS ( "a" ( 0xe820 ),
+					     "b" ( next ),
+					     "D" ( &__from_data16 ( e820buf )),
+					     "c" ( sizeof ( e820buf ) ),
+					     "d" ( SMAP ) ),
+			    CLOBBER ( "memory" ) );
+		if ( smap != SMAP )
+			return -ENOTSUP;
+		if ( flags & CF )
+			break;
+		DBG ( "E820 region [%llx,%llx) type %d\n", e820buf.start,
+		      ( e820buf.start + e820buf.len ), ( int ) e820buf.type );
+		if ( e820buf.type != E820_TYPE_RAM )
+			continue;
+		memmap[index].start = e820buf.start;
+		memmap[index].end = e820buf.start + e820buf.len;
+		index++;
+	} while ( ( index < entries ) && ( next != 0 ) );
+	return 0;
+}
+
+/**
+ * Get memory map
+ *
+ * @v memmap		Memory map to fill in
+ * @v entries		Maximum number of entries in memory map (minimum 2)
+ */
+void get_memmap ( struct memory_region *memmap, unsigned int entries ) {
+	unsigned int basemem, extmem;
+	int rc;
+
+	/* Clear memory map */
+	memset ( memmap, 0, ( entries * sizeof ( *memmap ) ) );
+
+	/* Get base and extended memory sizes */
+	basemem = basememsize();
+	extmem = extmemsize();
+
+	/* Try INT 15,e820 first */
+	if ( ( rc = meme820 ( memmap, entries ) ) == 0 )
+		return;
+
+	/* Fall back to constructing a map from basemem and extmem sizes */
+	memmap[0].end = ( basemem * 1024 );
+	memmap[1].start = 0x100000;
+	memmap[1].end = 0x100000 + ( extmem * 1024 );
+}