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Diffstat (limited to 'contrib/syslinux-4.02/com32/gpllib/memory.c')
| -rw-r--r-- | contrib/syslinux-4.02/com32/gpllib/memory.c | 445 |
1 files changed, 445 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/com32/gpllib/memory.c b/contrib/syslinux-4.02/com32/gpllib/memory.c new file mode 100644 index 0000000..28a95ff --- /dev/null +++ b/contrib/syslinux-4.02/com32/gpllib/memory.c @@ -0,0 +1,445 @@ +/* ----------------------------------------------------------------------- * + * + * Copyright 2009 Pierre-Alexandre Meyer + * + * Some parts borrowed from meminfo.c32: + * + * Copyright 2003-2009 H. Peter Anvin - All Rights Reserved + * Copyright 2009 Intel Corporation; author: H. Peter Anvin + * + * Some parts borrowed from Linux: + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright 2007 rPath, Inc. - All Rights Reserved + * Copyright 2009 Intel Corporation; author H. Peter Anvin + * + * Interrupt list from Ralf Brown (http://www.cs.cmu.edu/~ralf/files.html) + * + * This file is part of Syslinux, and is made available under + * the terms of the GNU General Public License version 2. + * + * ----------------------------------------------------------------------- */ + +#include <stdint.h> +#include <com32.h> +#include <string.h> +#include <memory.h> + +const char *const e820_types[] = { + "usable", + "reserved", + "ACPI reclaim", + "ACPI NVS", + "unusable", +}; + +struct e820_ext_entry { + struct e820entry std; + uint32_t ext_flags; +} __attribute__ ((packed)); + +#define SMAP 0x534d4150 /* ASCII "SMAP" */ + +void get_type(int type, char *type_ptr, int type_ptr_sz) +{ + unsigned int real_type = type - 1; + if (real_type < sizeof(e820_types) / sizeof(e820_types[0])) + strlcpy(type_ptr, e820_types[real_type], type_ptr_sz); +} + +/** + *INT 15 - newer BIOSes - GET SYSTEM MEMORY MAP + * AX = E820h + * EAX = 0000E820h + * EDX = 534D4150h ('SMAP') + * EBX = continuation value or 00000000h to start at beginning of map + * ECX = size of buffer for result, in bytes (should be >= 20 bytes) + * ES:DI -> buffer for result (see #00581) + * + * Return: CF clear if successful + * EAX = 534D4150h ('SMAP') + * ES:DI buffer filled + * EBX = next offset from which to copy or 00000000h if all done + * ECX = actual length returned in bytes + * CF set on error + * AH = error code (86h) (see #00496 at INT 15/AH=80h) + * + * Notes: originally introduced with the Phoenix BIOS v4.0, this function is + * now supported by most newer BIOSes, since various versions of Windows + * call it to find out about the system memory + * a maximum of 20 bytes will be transferred at one time, even if ECX is + * higher; some BIOSes (e.g. Award Modular BIOS v4.50PG) ignore the + * value of ECX on entry, and always copy 20 bytes + * some BIOSes expect the high word of EAX to be clear on entry, i.e. + * EAX=0000E820h + * if this function is not supported, an application should fall back + * to AX=E802h, AX=E801h, and then AH=88h + * the BIOS is permitted to return a nonzero continuation value in EBX + * and indicate that the end of the list has already been reached by + * returning with CF set on the next iteration + * this function will return base memory and ISA/PCI memory contiguous + * with base memory as normal memory ranges; it will indicate + * chipset-defined address holes which are not in use and motherboard + * memory-mapped devices, and all occurrences of the system BIOS as + * reserved; standard PC address ranges will not be reported + **/ +void detect_memory_e820(struct e820entry *desc, int size_map, int *size_found) +{ + int count = 0; + static struct e820_ext_entry buf; /* static so it is zeroed */ + + com32sys_t ireg, oreg; + memset(&ireg, 0, sizeof ireg); + + ireg.eax.w[0] = 0xe820; + ireg.edx.l = SMAP; + ireg.ecx.l = sizeof(struct e820_ext_entry); + ireg.edi.w[0] = OFFS(__com32.cs_bounce); + ireg.es = SEG(__com32.cs_bounce); + + /* + * Set this here so that if the BIOS doesn't change this field + * but still doesn't change %ecx, we're still okay... + */ + memset(&buf, 0, sizeof buf); + buf.ext_flags = 1; + + do { + memcpy(__com32.cs_bounce, &buf, sizeof buf); + + /* Important: %edx and %esi are clobbered by some BIOSes, + so they must be either used for the error output + or explicitly marked clobbered. Given that, assume there + is something out there clobbering %ebp and %edi, too. */ + __intcall(0x15, &ireg, &oreg); + + /* Some BIOSes stop returning SMAP in the middle of + the search loop. We don't know exactly how the BIOS + screwed up the map at that point, we might have a + partial map, the full map, or complete garbage, so + just return failure. */ + if (oreg.eax.l != SMAP) { + count = 0; + break; + } + + if (oreg.eflags.l & EFLAGS_CF || oreg.ecx.l < 20) + break; + + memcpy(&buf, __com32.cs_bounce, sizeof buf); + + /* + * ACPI 3.0 added the extended flags support. If bit 0 + * in the extended flags is zero, we're supposed to simply + * ignore the entry -- a backwards incompatible change! + */ + if (oreg.ecx.l > 20 && !(buf.ext_flags & 1)) + continue; + + memcpy(&desc[count], &buf, sizeof buf); + count++; + + /* Set continuation value */ + ireg.ebx.l = oreg.ebx.l; + } while (ireg.ebx.l && count < size_map); + + *size_found = count; +} + +/** + * detect_memory_e801 + * + *INT 15 - Phoenix BIOS v4.0 - GET MEMORY SIZE FOR >64M CONFIGURATIONS + * AX = E801h + * + * Return: CF clear if successful + * AX = extended memory between 1M and 16M, in K (max 3C00h = 15MB) + * BX = extended memory above 16M, in 64K blocks + * CX = configured memory 1M to 16M, in K + * DX = configured memory above 16M, in 64K blocks + * CF set on error + * + * Notes: supported by the A03 level (6/14/94) and later XPS P90 BIOSes, as well + * as the Compaq Contura, 3/8/93 DESKPRO/i, and 7/26/93 LTE Lite 386 ROM + * BIOS + * supported by AMI BIOSes dated 8/23/94 or later + * on some systems, the BIOS returns AX=BX=0000h; in this case, use CX + * and DX instead of AX and BX + * this interface is used by Windows NT 3.1, OS/2 v2.11/2.20, and is + * used as a fall-back by newer versions if AX=E820h is not supported + * this function is not used by MS-DOS 6.0 HIMEM.SYS when an EISA machine + * (for example with parameter /EISA) (see also MEM F000h:FFD9h), or no + * Compaq machine was detected, or parameter /NOABOVE16 was given. + **/ +int detect_memory_e801(int *mem_size_below_16, int *mem_size_above_16) +{ + com32sys_t ireg, oreg; + memset(&ireg, 0, sizeof ireg); + + ireg.eax.w[0] = 0xe801; + + __intcall(0x15, &ireg, &oreg); + + if (oreg.eflags.l & EFLAGS_CF) + return -1; + + if (oreg.eax.w[0] > 0x3c00) + return -1; /* Bogus! */ + + /* Linux seems to use ecx and edx by default if they are defined */ + if (oreg.eax.w[0] || oreg.eax.w[0]) { + oreg.eax.w[0] = oreg.ecx.w[0]; + oreg.ebx.w[0] = oreg.edx.w[0]; + } + + *mem_size_below_16 = oreg.eax.w[0]; /* 1K blocks */ + *mem_size_above_16 = oreg.ebx.w[0]; /* 64K blocks */ + + return 0; +} + +int detect_memory_88(int *mem_size) +{ + com32sys_t ireg, oreg; + memset(&ireg, 0, sizeof ireg); + + ireg.eax.w[0] = 0x8800; + + __intcall(0x15, &ireg, &oreg); + + if (oreg.eflags.l & EFLAGS_CF) + return -1; + + *mem_size = oreg.eax.w[0]; + return 0; +} + +/* + * Sanitize the BIOS e820 map. + * + * This code come from the memtest86 project. It have been adjusted to match + * the syslinux environement. + * Some e820 responses include overlapping entries. The following + * replaces the original e820 map with a new one, removing overlaps. + * + * The following stuff could be merge once the addr_t will be set to 64bits. + * syslinux_scan_memory can be used for that purpose + */ +int sanitize_e820_map(struct e820entry *orig_map, struct e820entry *new_bios, + short old_nr) +{ + struct change_member { + struct e820entry *pbios; /* pointer to original bios entry */ + unsigned long long addr; /* address for this change point */ + }; + struct change_member change_point_list[2 * E820MAX]; + struct change_member *change_point[2 * E820MAX]; + struct e820entry *overlap_list[E820MAX]; + struct e820entry biosmap[E820MAX]; + struct change_member *change_tmp; + unsigned long current_type, last_type; + unsigned long long last_addr; + int chgidx, still_changing; + int overlap_entries; + int new_bios_entry; + int i; + + /* + Visually we're performing the following (1,2,3,4 = memory types)... + Sample memory map (w/overlaps): + ____22__________________ + ______________________4_ + ____1111________________ + _44_____________________ + 11111111________________ + ____________________33__ + ___________44___________ + __________33333_________ + ______________22________ + ___________________2222_ + _________111111111______ + _____________________11_ + _________________4______ + + Sanitized equivalent (no overlap): + 1_______________________ + _44_____________________ + ___1____________________ + ____22__________________ + ______11________________ + _________1______________ + __________3_____________ + ___________44___________ + _____________33_________ + _______________2________ + ________________1_______ + _________________4______ + ___________________2____ + ____________________33__ + ______________________4_ + */ + /* First make a copy of the map */ + for (i = 0; i < old_nr; i++) { + biosmap[i].addr = orig_map[i].addr; + biosmap[i].size = orig_map[i].size; + biosmap[i].type = orig_map[i].type; + } + + /* bail out if we find any unreasonable addresses in bios map */ + for (i = 0; i < old_nr; i++) { + if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) + return 0; + } + + /* create pointers for initial change-point information (for sorting) */ + for (i = 0; i < 2 * old_nr; i++) + change_point[i] = &change_point_list[i]; + + /* record all known change-points (starting and ending addresses) */ + chgidx = 0; + for (i = 0; i < old_nr; i++) { + change_point[chgidx]->addr = biosmap[i].addr; + change_point[chgidx++]->pbios = &biosmap[i]; + change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; + change_point[chgidx++]->pbios = &biosmap[i]; + } + + /* sort change-point list by memory addresses (low -> high) */ + still_changing = 1; + while (still_changing) { + still_changing = 0; + for (i = 1; i < 2 * old_nr; i++) { + /* if <current_addr> > <last_addr>, swap */ + /* or, if current=<start_addr> & last=<end_addr>, swap */ + if ((change_point[i]->addr < change_point[i - 1]->addr) || + ((change_point[i]->addr == change_point[i - 1]->addr) && + (change_point[i]->addr == change_point[i]->pbios->addr) && + (change_point[i - 1]->addr != + change_point[i - 1]->pbios->addr)) + ) { + change_tmp = change_point[i]; + change_point[i] = change_point[i - 1]; + change_point[i - 1] = change_tmp; + still_changing = 1; + } + } + } + + /* create a new bios memory map, removing overlaps */ + overlap_entries = 0; /* number of entries in the overlap table */ + new_bios_entry = 0; /* index for creating new bios map entries */ + last_type = 0; /* start with undefined memory type */ + last_addr = 0; /* start with 0 as last starting address */ + /* loop through change-points, determining affect on the new bios map */ + for (chgidx = 0; chgidx < 2 * old_nr; chgidx++) { + /* keep track of all overlapping bios entries */ + if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) { + /* add map entry to overlap list (> 1 entry implies an overlap) */ + overlap_list[overlap_entries++] = change_point[chgidx]->pbios; + } else { + /* remove entry from list (order independent, so swap with last) */ + for (i = 0; i < overlap_entries; i++) { + if (overlap_list[i] == change_point[chgidx]->pbios) + overlap_list[i] = overlap_list[overlap_entries - 1]; + } + overlap_entries--; + } + /* if there are overlapping entries, decide which "type" to use */ + /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */ + current_type = 0; + for (i = 0; i < overlap_entries; i++) + if (overlap_list[i]->type > current_type) + current_type = overlap_list[i]->type; + /* continue building up new bios map based on this information */ + if (current_type != last_type) { + if (last_type != 0) { + new_bios[new_bios_entry].size = + change_point[chgidx]->addr - last_addr; + /* move forward only if the new size was non-zero */ + if (new_bios[new_bios_entry].size != 0) + if (++new_bios_entry >= E820MAX) + break; /* no more space left for new bios entries */ + } + if (current_type != 0) { + new_bios[new_bios_entry].addr = change_point[chgidx]->addr; + new_bios[new_bios_entry].type = current_type; + last_addr = change_point[chgidx]->addr; + } + last_type = current_type; + } + } + return (new_bios_entry); +} + +/* The following stuff could be merge once the addr_t will be set to 64bits. + * syslinux_scan_memory can be used for that purpose */ +unsigned long detect_memsize(void) +{ + unsigned long memory_size = 0; + + /* Try to detect memory via e820 */ + struct e820entry map[E820MAX]; + int count = 0; + detect_memory_e820(map, E820MAX, &count); + memory_size = memsize_e820(map, count); + if (memory_size > 0) + return memory_size; + + /*e820 failed, let's try e801 */ + int mem_low, mem_high = 0; + if (!detect_memory_e801(&mem_low, &mem_high)) + return mem_low + (mem_high << 6); + + /*e801 failed, let's try e88 */ + int mem_size = 0; + if (!detect_memory_88(&mem_size)) + return mem_size; + + /* We were enable to detect any kind of memory */ + return 0; +} + +/* The following stuff could be merge once the addr_t will be set to 64bits. + * syslinux_scan_memory can be used for that purpose */ +unsigned long memsize_e820(struct e820entry *e820, int e820_nr) +{ + int i, n, nr; + unsigned long memory_size = 0; + struct e820entry nm[E820MAX]; + + /* Clean up, adjust and copy the BIOS-supplied E820-map. */ + nr = sanitize_e820_map(e820, nm, e820_nr); + + /* If there is not a good 820 map returning 0 to indicate + that we don't have any idea of the amount of ram we have */ + if (nr < 1 || nr > E820MAX) { + return 0; + } + + /* Build the memory map for testing */ + n = 0; + for (i = 0; i < nr; i++) { + if (nm[i].type == E820_RAM || nm[i].type == E820_ACPI) { + unsigned long long start; + unsigned long long end; + start = nm[i].addr; + end = start + nm[i].size; + + /* Don't ever use memory between 640 and 1024k */ + if (start > RES_START && start < RES_END) { + if (end < RES_END) { + continue; + } + start = RES_END; + } + if (end > RES_START && end < RES_END) { + end = RES_START; + } + memory_size += (end >> 12) - ((start + 4095) >> 12); + n++; + } else if (nm[i].type == E820_NVS) { + memory_size += nm[i].size >> 12; + } + } + return memory_size * 4; +} |