--- linux-2.2.13/include/asm-i386/e820.h.orig Thu Nov 18 13:31:21 1999
+++ linux-2.2.13/include/asm-i386/e820.h Fri Nov 19 07:33:56 1999
@@ -0,0 +1,54 @@
+/*
+ * structures and definitions for the int 15, ax=e820 memory map
+ * scheme.
+ *
+ * In a nutshell, arch/i386/boot/setup.S populates a scratch table
+ * in the empty_zero_block that contains a list of usable address/size
+ * duples. In arch/i386/kernel/setup.c, this information is
+ * transferred into the e820map, and in arch/i386/mm/init.c, that
+ * new information is used to mark pages reserved or not.
+ *
+ */
+#ifndef __E820_HEADER
+#define __E820_HEADER
+
+#define E820MAP 0x2d0 /* our map */
+#define E820MAX 32 /* number of entries in E820MAP */
+#define E820NR 0x1e8 /* # entries in E820MAP */
+
+#define E820_RAM 1 /* Memory available to OS. */
+#define E820_RESERVED 2 /* Memory reserved for BIOS. */
+#define E820_ACPI 3 /* Memory for ACPI. */
+#define E820_NVS 4 /* Memory for NVS. */
+
+/* Memory available to OS. */
+#define E820_AVAILABLE 0x80000000
+
+/* Memory region is ok. */
+#define E820_REG_OK(m) ((m).addrhigh == 0x0 && (m).sizehigh == 0x0)
+
+/* Memory region type is ok. */
+#define E820_TYPE_OK(m) ((m).type == E820_RAM)
+
+#ifndef __ASSEMBLY__
+
+struct e820map {
+ int nr_map;
+ struct {
+ /* low 4 bytes of start of memory segment */
+ unsigned long addrlow;
+ /* high 4 bytes of start of memory segment */
+ unsigned long addrhigh;
+ /* low 4 bytes of size of memory segment */
+ unsigned long sizelow;
+ /* high 4 bytes of size of memory segment */
+ unsigned long sizehigh;
+ /* type of memory segment */
+ unsigned long type;
+ } map[E820MAX];
+};
+
+extern struct e820map e820;
+#endif/*!__ASSEMBLY__*/
+
+#endif/*__E820_HEADER*/
--- linux-2.2.13/Documentation/i386/zero-page.txt.orig Thu Nov 18 13:18:51 1999
+++ linux-2.2.13/Documentation/i386/zero-page.txt Thu Nov 18 13:18:54 1999
@@ -30,6 +30,7 @@ Offset Type Description
0xb0 - 0x1df Free. Add more parameters here if you really need them.
0x1e0 unsigned long ALT_MEM_K, alternative mem check, in Kb
+0x1e8 char number of entries in E820MAP (below)
0x1f1 char size of setup.S, number of sectors
0x1f2 unsigned short MOUNT_ROOT_RDONLY (if !=0)
0x1f4 unsigned short size of compressed kernel-part in the
@@ -64,7 +65,7 @@ Offset Type Description
0x21c unsigned long INITRD_SIZE, size in bytes of ramdisk image
0x220 4 bytes (setup.S)
0x224 unsigned short setup.S heap end pointer
-0x226 - 0x7ff setup.S code.
+0x2d0 - 0x550 E820MAP
0x800 string, 2K max COMMAND_LINE, the kernel commandline as
copied using CL_OFFSET.
--- linux-2.2.13/arch/i386/boot/setup.S.orig Thu Nov 18 13:18:51 1999
+++ linux-2.2.13/arch/i386/boot/setup.S Thu Nov 18 13:18:55 1999
@@ -37,6 +37,7 @@
#include <linux/version.h>
#include <linux/compile.h>
#include <asm/boot.h>
+#include <asm/e820.h>
! Signature words to ensure LILO loaded us right
#define SIG1 0xAA55
@@ -59,7 +60,7 @@ begbss:
entry start
start:
- jmp start_of_setup
+ jmp trampoline
! ------------------------ start of header --------------------------------
!
! SETUP-header, must start at CS:2 (old 0x9020:2)
@@ -119,6 +120,8 @@ bootsect_kludge:
heap_end_ptr: .word modelist+1024 ! space from here (exclusive) down to
! end of setup code can be used by setup
! for local heap purposes.
+trampoline: call start_of_setup
+ .space 1024
! ------------------------ end of header ----------------------------------
start_of_setup:
@@ -245,37 +248,87 @@ loader_panic_mess:
loader_ok:
! Get memory size (extended mem, kB)
+ xor eax, eax ! preload new memory slots with 0k
+ mov dword ptr [0x1e0], eax
#ifndef STANDARD_MEMORY_BIOS_CALL
- push ebx
+ mov byte ptr [E820NR], al
+! Try three different memory detection schemes. First, try
+! e820h, which lets us assemble a memory map, then try e801h,
+! which returns a 32-bit memory size, and finally 88h, which
+! returns 0-64m
+
+! method E820H:
+! the memory map from hell. e820h returns memory classified into
+! a whole bunch of different types, and allows memory holes and
+! everything. We scan through this memory map and build a list
+! of the first 32 memory areas, which we return at [E820MAP].
+!
+meme820:
+ mov edx, #0x534d4150 ! ascii `SMAP'
+ xor ebx, ebx ! continuation counter
+
+ mov di, #E820MAP ! point into the whitelist
+ ! so we can have the bios
+ ! directly write into it.
+
+jmpe820:
+ mov eax, #0x0000e820 ! e820, upper word zeroed
+ mov ecx, #20 ! size of the e820rec
+
+ push ds ! data record.
+ pop es
+ int 0x15 ! make the call
+ jc bail820 ! fall to e801 if it fails
- xor ebx,ebx ! preload new memory slot with 0k
- mov [0x1e0], ebx
+ cmp eax, #0x534d4150 ! check the return is `SMAP'
+ jne bail820 ! fall to e801 if it fails
- mov ax,#0xe801
- int 0x15
- jc oldstylemem
-
-! Memory size is in 1 k chunksizes, to avoid confusing loadlin.
-! We store the 0xe801 memory size in a completely different place,
+! cmp dword ptr [16+di], #1 ! is this usable memory?
+! jne again820
+
+ ! If this is usable memory, we save it by simply advancing di by
+ ! sizeof(e820rec).
+ !
+good820:
+ mov al, byte ptr [E820NR] ! up to 32 good entries, that is
+ cmp al, #E820MAX
+ jnl bail820
+ inc byte ptr [E820NR]
+ mov ax, di
+ add ax, #20
+ mov di, ax
+
+again820:
+ cmp ebx, #0 ! check to see if ebx is
+ jne jmpe820 ! set to EOF
+
+bail820:
+
+
+! method E801H:
+! memory size is in 1k chunksizes, to avoid confusing loadlin.
+! we store the 0xe801 memory size in a completely different place,
! because it will most likely be longer than 16 bits.
! (use 1e0 because that's what Larry Augustine uses in his
! alternative new memory detection scheme, and it's sensible
! to write everything into the same place.)
+meme801:
- and ebx, #0xffff ! clear sign extend
- shl ebx, 6 ! and go from 64k to 1k chunks
- mov [0x1e0],ebx ! store extended memory size
-
- and eax, #0xffff ! clear sign extend
- add [0x1e0],eax ! and add lower memory into total size.
-
- ! and fall into the old memory detection code to populate the
- ! compatibility slot.
+ mov ax,#0xe801
+ int 0x15
+ jc mem88
+
+ and edx, #0xffff ! clear sign extend
+ shl edx, 6 ! and go from 64k to 1k chunks
+ mov [0x1e0],edx ! store extended memory size
+
+ and ecx, #0xffff ! clear sign extend
+ add [0x1e0],ecx ! and add lower memory into total size.
+
+! Ye Olde Traditional Methode. Returns the memory size (up to 16mb or
+! 64mb, depending on the bios) in ax.
+mem88:
-oldstylemem:
- pop ebx
-#else
- mov dword ptr [0x1e0], #0
#endif
mov ah,#0x88
int 0x15
--- linux-2.2.13/arch/i386/kernel/setup.c.orig Thu Nov 18 13:18:51 1999
+++ linux-2.2.13/arch/i386/kernel/setup.c Fri Nov 19 07:26:20 1999
@@ -59,6 +59,7 @@
#include <asm/cobalt.h>
#include <asm/msr.h>
#include <asm/dma.h>
+#include <asm/e820.h>
/*
* Machine setup..
@@ -92,6 +93,8 @@ struct sys_desc_table_struct {
unsigned char table[0];
};
+struct e820map e820 = { 0 };
+
unsigned char aux_device_present;
#ifdef CONFIG_BLK_DEV_RAM
@@ -117,6 +120,8 @@ int disable_x86_serial_nr = 0;
#define SCREEN_INFO (*(struct screen_info *) (PARAM+0))
#define EXT_MEM_K (*(unsigned short *) (PARAM+2))
#define ALT_MEM_K (*(unsigned long *) (PARAM+0x1e0))
+#define E820_MAP_NR (*(char*) (PARAM+E820NR))
+#define E820_MAP ((unsigned long *) (PARAM+E820MAP))
#define APM_BIOS_INFO (*(struct apm_bios_info *) (PARAM+0x40))
#define DRIVE_INFO (*(struct drive_info_struct *) (PARAM+0x80))
#define SYS_DESC_TABLE (*(struct sys_desc_table_struct*)(PARAM+0xa0))
@@ -297,9 +302,37 @@ __initfunc(void setup_arch(char **cmdlin
#ifndef STANDARD_MEMORY_BIOS_CALL
{
unsigned long memory_alt_end = (1<<20) + (ALT_MEM_K<<10);
- /* printk(KERN_DEBUG "Memory sizing: %08x %08x\n", memory_end, memory_alt_end); */
+ unsigned long mem_high;
+ int i;
+
if (memory_alt_end > memory_end)
memory_end = memory_alt_end;
+ else
+ memory_alt_end = memory_end;
+
+ e820.nr_map = E820_MAP_NR;
+ if (e820.nr_map > E820MAX)
+ e820.nr_map = E820MAX;
+ memcpy(e820.map, E820_MAP, e820.nr_map * sizeof e820.map[0]);
+
+ /* If a memory region is below "memory_alt_end", it
+ will be marked as available. Above "memory_alt_end",
+ we have to use E820_TYPE_OK. */
+ mem_high = 0;
+ for (i=0; i < e820.nr_map; i++) {
+ if (E820_REG_OK(e820.map[i])
+ && (e820.map[i].addrlow < memory_alt_end
+ || (E820_TYPE_OK(e820.map[i])
+ && mem_high == e820.map[i].addrlow))) {
+ mem_high = e820.map[i].addrlow
+ + e820.map[i].sizelow;
+ e820.map[i].type |= E820_AVAILABLE;
+ if (mem_high > memory_end)
+ memory_end = mem_high;
+ }
+ else
+ break;
+ }
}
#endif
--- linux-2.2.13/arch/i386/mm/init.c.orig Thu Nov 18 13:18:51 1999
+++ linux-2.2.13/arch/i386/mm/init.c Thu Nov 18 13:18:55 1999
@@ -30,6 +30,7 @@
#include <asm/pgtable.h>
#include <asm/dma.h>
#include <asm/fixmap.h>
+#include <asm/e820.h>
extern void show_net_buffers(void);
extern unsigned long init_smp_mappings(unsigned long);
@@ -416,6 +417,50 @@ __initfunc(void mem_init(unsigned long s
int initpages = 0;
int bigpages = 0;
unsigned long tmp;
+ unsigned long start_seg = 0;
+ unsigned long size_seg = ~0;
+ int nr_map = 0;
+ int i, type;
+ const char *available;
+ const char *mem_type [] = {
+ "usable",
+ "reserved",
+ "ACPI data",
+ "NVS data"
+
+ };
+
+ for (i=0; i < e820.nr_map; i++) {
+ available = (e820.map[i].type & E820_AVAILABLE)
+ ? "available" : "unavailable";
+ type = e820.map[i].type & ~E820_AVAILABLE;
+ switch (type) {
+ case E820_RAM:
+ case E820_RESERVED:
+ case E820_ACPI:
+ case E820_NVS:
+ type--;
+ printk("e820 region %d: (%lu, %lu) @ 0x%08lx%08lx (%s) [%s]\n",
+ i, e820.map[i].sizehigh, e820.map[i].sizelow,
+ e820.map[i].addrhigh, e820.map[i].addrlow,
+ mem_type [type], available);
+ break;
+ default:
+ printk("e820 region %d: (%lu, %lu) @ 0x%08lx%08lx (type %d) [%s]\n",
+ i, e820.map[i].sizehigh, e820.map[i].sizelow,
+ e820.map[i].addrhigh, e820.map[i].addrlow,
+ type, available);
+ break;
+ }
+ }
+
+ if (nr_map < e820.nr_map
+ && (e820.map[i].type & E820_AVAILABLE)) {
+ start_seg = e820.map[nr_map].addrlow + PAGE_OFFSET;
+ size_seg = e820.map[nr_map].sizelow;
+ nr_map++;
+ }
+
end_mem &= PAGE_MASK;
#ifdef CONFIG_BIGMEM
@@ -455,7 +500,22 @@ __initfunc(void mem_init(unsigned long s
}
while (start_mem < end_mem) {
- clear_bit(PG_reserved, &mem_map[MAP_NR(start_mem)].flags);
+ if (start_mem > start_seg) {
+ if (start_mem < start_seg + size_seg)
+ clear_bit(PG_reserved,
+ &mem_map[MAP_NR(start_mem)].flags);
+ else if (nr_map < e820.nr_map
+ && (e820.map[i].type & E820_AVAILABLE)) {
+ start_seg = e820.map[nr_map].addrlow + PAGE_OFFSET;
+ size_seg = e820.map[nr_map].sizelow;
+ nr_map++;
+ continue; /* be paranoid in case the */
+ /* e820 code hasn't collapsed */
+ /* adjacent usable memory */
+ }
+ else
+ break; /* no more valid memory */
+ }
start_mem += PAGE_SIZE;
}
for (tmp = PAGE_OFFSET ; tmp < end_mem ; tmp += PAGE_SIZE) {
