+++ /dev/null
-/*
- * Handle the memory map.
- * The functions here do the job until bootmem takes over.
- * $Id: e820.c,v 1.4 2002/09/19 19:25:32 ak Exp $
- *
- * Getting sanitize_e820_map() in sync with i386 version by applying change:
- * - Provisions for empty E820 memory regions (reported by certain BIOSes).
- * Alex Achenbach <xela@slit.de>, December 2002.
- * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
- *
- */
-#include <lwk/kernel.h>
-#include <lwk/types.h>
-#include <lwk/init.h>
-#include <lwk/bootmem.h>
-#include <lwk/resource.h>
-#include <lwk/string.h>
-#include <lwk/linux_compat.h>
-
-#include <arch/page.h>
-#include <arch/pgtable.h>
-#include <arch/e820.h>
-#include <arch/proto.h>
-#include <arch/bootsetup.h>
-#include <arch/sections.h>
-
-/**
- * The BIOS "e820" map of memory.
- */
-struct e820map e820;
-
-/*
- * PFN of last memory page.
- */
-unsigned long end_pfn;
-EXPORT_SYMBOL(end_pfn);
-
-/*
- * end_pfn only includes RAM, while end_pfn_map includes all e820 entries.
- * The direct mapping extends to end_pfn_map, so that we can directly access
- * apertures, ACPI and other tables without having to play with fixmaps.
- */
-unsigned long end_pfn_map;
-
-/*
- * Last pfn which the user wants to use.
- */
-unsigned long end_user_pfn = MAXMEM>>PAGE_SHIFT;
-
-extern struct resource code_resource, data_resource;
-
-/* Check for some hardcoded bad areas that early boot is not allowed to touch */
-static inline int bad_addr(unsigned long *addrp, unsigned long size)
-{
- unsigned long addr = *addrp, last = addr + size;
-
- /* various gunk below that needed for SMP startup */
- if (addr < 0x8000) {
- *addrp = 0x8000;
- return 1;
- }
-
- /* direct mapping tables of the kernel */
- if (last >= table_start<<PAGE_SHIFT && addr < table_end<<PAGE_SHIFT) {
- *addrp = table_end << PAGE_SHIFT;
- return 1;
- }
-
- /* initrd image */
- if (LOADER_TYPE && INITRD_START && last >= INITRD_START &&
- addr < INITRD_START+INITRD_SIZE) {
- *addrp = INITRD_START + INITRD_SIZE;
- return 1;
- }
-
- /* kernel code + 640k memory hole (later should not be needed, but
- be paranoid for now) */
- if (last >= 640*1024 && addr < __pa_symbol(&_end)) {
- *addrp = __pa_symbol(&_end);
- return 1;
- }
-
- if (last >= ebda_addr && addr < ebda_addr + ebda_size) {
- *addrp = ebda_addr + ebda_size;
- return 1;
- }
-
- /* XXX ramdisk image here? */
- return 0;
-}
-
-/*
- * This function checks if any part of the range <start,end> is mapped
- * with type.
- */
-int __init
-e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
-{
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- if (type && ei->type != type)
- continue;
- if (ei->addr >= end || ei->addr + ei->size <= start)
- continue;
- return 1;
- }
- return 0;
-}
-
-/*
- * This function checks if the entire range <start,end> is mapped with type.
- *
- * Note: this function only works correct if the e820 table is sorted and
- * not-overlapping, which is the case
- */
-int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
-{
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- if (type && ei->type != type)
- continue;
- /* is the region (part) in overlap with the current region ?*/
- if (ei->addr >= end || ei->addr + ei->size <= start)
- continue;
-
- /* if the region is at the beginning of <start,end> we move
- * start to the end of the region since it's ok until there
- */
- if (ei->addr <= start)
- start = ei->addr + ei->size;
- /* if start is now at or beyond end, we're done, full coverage */
- if (start >= end)
- return 1; /* we're done */
- }
- return 0;
-}
-
-/*
- * Find a free area in a specific range.
- */
-unsigned long __init find_e820_area(unsigned long start, unsigned long end, unsigned size)
-{
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- unsigned long addr = ei->addr, last;
- if (ei->type != E820_RAM)
- continue;
- if (addr < start)
- addr = start;
- if (addr > ei->addr + ei->size)
- continue;
- while (bad_addr(&addr, size) && addr+size <= ei->addr+ei->size)
- ;
- last = addr + size;
- if (last > ei->addr + ei->size)
- continue;
- if (last > end)
- continue;
- return addr;
- }
- return -1UL;
-}
-
-/*
- * Free bootmem based on the e820 table for a node.
- */
-void __init e820_bootmem_free(unsigned long start, unsigned long end)
-{
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- unsigned long last, addr;
-
- if (ei->type != E820_RAM ||
- ei->addr+ei->size <= start ||
- ei->addr >= end)
- continue;
-
- addr = round_up(ei->addr, PAGE_SIZE);
- if (addr < start)
- addr = start;
-
- last = round_down(ei->addr + ei->size, PAGE_SIZE);
- if (last >= end)
- last = end;
-
- if (last > addr && last-addr >= PAGE_SIZE)
- free_bootmem(addr, last-addr);
- }
-}
-
-/*
- * Find the highest page frame number we have available
- */
-unsigned long __init e820_end_of_ram(void)
-{
- int i;
- unsigned long end_pfn = 0;
-
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- unsigned long start, end;
-
- start = round_up(ei->addr, PAGE_SIZE);
- end = round_down(ei->addr + ei->size, PAGE_SIZE);
- if (start >= end)
- continue;
- if (ei->type == E820_RAM) {
- if (end > end_pfn<<PAGE_SHIFT)
- end_pfn = end>>PAGE_SHIFT;
- } else {
- if (end > end_pfn_map<<PAGE_SHIFT)
- end_pfn_map = end>>PAGE_SHIFT;
- }
- }
-
- if (end_pfn > end_pfn_map)
- end_pfn_map = end_pfn;
- if (end_pfn_map > MAXMEM>>PAGE_SHIFT)
- end_pfn_map = MAXMEM>>PAGE_SHIFT;
- if (end_pfn > end_user_pfn)
- end_pfn = end_user_pfn;
- if (end_pfn > end_pfn_map)
- end_pfn = end_pfn_map;
-
- return end_pfn;
-}
-
-/*
- * Compute how much memory is missing in a range.
- * Unlike the other functions in this file the arguments are in page numbers.
- */
-unsigned long __init
-e820_hole_size(unsigned long start_pfn, unsigned long end_pfn)
-{
- unsigned long ram = 0;
- unsigned long start = start_pfn << PAGE_SHIFT;
- unsigned long end = end_pfn << PAGE_SHIFT;
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct e820entry *ei = &e820.map[i];
- unsigned long last, addr;
-
- if (ei->type != E820_RAM ||
- ei->addr+ei->size <= start ||
- ei->addr >= end)
- continue;
-
- addr = round_up(ei->addr, PAGE_SIZE);
- if (addr < start)
- addr = start;
-
- last = round_down(ei->addr + ei->size, PAGE_SIZE);
- if (last >= end)
- last = end;
-
- if (last > addr)
- ram += last - addr;
- }
- return ((end - start) - ram) >> PAGE_SHIFT;
-}
-
-/*
- * Mark e820 reserved areas as busy for the resource manager.
- */
-void __init e820_reserve_resources(void)
-{
- int i;
- for (i = 0; i < e820.nr_map; i++) {
- struct resource *res;
- res = alloc_bootmem(sizeof(struct resource));
- switch (e820.map[i].type) {
- case E820_RAM: res->name = "System RAM"; break;
- case E820_ACPI: res->name = "ACPI Tables"; break;
- case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
- default: res->name = "reserved";
- }
- res->start = e820.map[i].addr;
- res->end = res->start + e820.map[i].size - 1;
- res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
- request_resource(&iomem_resource, res);
- if (e820.map[i].type == E820_RAM) {
- /*
- * We don't know which RAM region contains kernel data,
- * so we try it repeatedly and let the resource manager
- * test it.
- */
- request_resource(res, &code_resource);
- request_resource(res, &data_resource);
-#ifdef CONFIG_KEXEC
- request_resource(res, &crashk_res);
-#endif
- }
- }
-}
-
-/*
- * Add a memory region to the kernel e820 map.
- */
-void __init add_memory_region(unsigned long start, unsigned long size, int type)
-{
- int x = e820.nr_map;
-
- if (x == E820MAX) {
- printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
- return;
- }
-
- e820.map[x].addr = start;
- e820.map[x].size = size;
- e820.map[x].type = type;
- e820.nr_map++;
-}
-
-void __init e820_print_map(char *who)
-{
- int i;
- char type[16];
- size_t total_size = 0;
-
- for (i = 0; i < e820.nr_map; i++) {
- const struct e820entry * entry = &e820.map[i];
- switch (entry->type) {
- case E820_RAM: sprintf(type, "(usable)\n");
- total_size += entry->size;
- break;
- case E820_RESERVED:
- sprintf(type, "(reserved)\n");
- break;
- case E820_ACPI:
- sprintf(type, "(ACPI data)\n");
- break;
- case E820_NVS:
- sprintf(type, "(ACPI NVS)\n");
- break;
- default: sprintf(type, "type %u\n", entry->type);
- break;
- }
-
- printk(KERN_DEBUG
- " %s: %016Lx - %016Lx %s",
- who,
- (unsigned long long) entry->addr,
- (unsigned long long) (entry->addr + entry->size),
- type);
- }
-
- printk( KERN_DEBUG "Total usable memory %ld bytes\n", total_size );
-}
-
-/*
- * Sanitize the BIOS e820 map.
- *
- * Some e820 responses include overlapping entries. The following
- * replaces the original e820 map with a new one, removing overlaps.
- *
- */
-static int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
-{
- struct change_member {
- struct e820entry *pbios; /* pointer to original bios entry */
- unsigned long long addr; /* address for this change point */
- };
- static struct change_member change_point_list[2*E820MAX] __initdata;
- static struct change_member *change_point[2*E820MAX] __initdata;
- static struct e820entry *overlap_list[E820MAX] __initdata;
- static struct e820entry new_bios[E820MAX] __initdata;
- 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 old_nr, new_nr, chg_nr;
- 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_
- */
-
- /* if there's only one memory region, don't bother */
- if (*pnr_map < 2)
- return -1;
-
- old_nr = *pnr_map;
-
- /* 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 -1;
-
- /* 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),
- omitting those that are for empty memory regions */
- chgidx = 0;
- for (i=0; i < old_nr; i++) {
- if (biosmap[i].size != 0) {
- 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];
- }
- }
- chg_nr = chgidx;
-
- /* sort change-point list by memory addresses (low -> high) */
- still_changing = 1;
- while (still_changing) {
- still_changing = 0;
- for (i=1; i < chg_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 < chg_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;
- }
- }
- new_nr = new_bios_entry; /* retain count for new bios entries */
-
- /* copy new bios mapping into original location */
- memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry));
- *pnr_map = new_nr;
-
- return 0;
-}
-
-/*
- * Copy the BIOS e820 map into a safe place.
- *
- * Sanity-check it while we're at it..
- *
- * If we're lucky and live on a modern system, the setup code
- * will have given us a memory map that we can use to properly
- * set up memory. If we aren't, we'll fake a memory map.
- *
- * We check to see that the memory map contains at least 2 elements
- * before we'll use it, because the detection code in setup.S may
- * not be perfect and most every PC known to man has two memory
- * regions: one from 0 to 640k, and one from 1mb up. (The IBM
- * thinkpad 560x, for example, does not cooperate with the memory
- * detection code.)
- */
-static int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
-{
- /* Only one memory region (or negative)? Ignore it */
- if (nr_map < 2)
- return -1;
-
- do {
- unsigned long start = biosmap->addr;
- unsigned long size = biosmap->size;
- unsigned long end = start + size;
- unsigned long type = biosmap->type;
-
- /* Overflow in 64 bits? Ignore the memory map. */
- if (start > end)
- return -1;
-
- /*
- * Some BIOSes claim RAM in the 640k - 1M region.
- * Not right. Fix it up.
- *
- * This should be removed on Hammer which is supposed to not
- * have non e820 covered ISA mappings there, but I had some strange
- * problems so it stays for now. -AK
- */
- if (type == E820_RAM) {
- if (start < 0x100000ULL && end > 0xA0000ULL) {
- if (start < 0xA0000ULL)
- add_memory_region(start, 0xA0000ULL-start, type);
- if (end <= 0x100000ULL)
- continue;
- start = 0x100000ULL;
- size = end - start;
- }
- }
-
- add_memory_region(start, size, type);
- } while (biosmap++,--nr_map);
- return 0;
-}
-
-void __init setup_memory_region(void)
-{
- char *who = "BIOS-e820";
-
- /*
- * Try to copy the BIOS-supplied E820-map.
- *
- * Otherwise fake a memory map; one section from 0k->640k,
- * the next section from 1mb->appropriate_mem_k
- */
- sanitize_e820_map(E820_MAP, &E820_MAP_NR);
- if (copy_e820_map(E820_MAP, E820_MAP_NR) < 0) {
- unsigned long mem_size;
-
- /* compare results from other methods and take the greater */
- if (ALT_MEM_K < EXT_MEM_K) {
- mem_size = EXT_MEM_K;
- who = "BIOS-88";
- } else {
- mem_size = ALT_MEM_K;
- who = "BIOS-e801";
- }
-
- e820.nr_map = 0;
- add_memory_region(0, LOWMEMSIZE(), E820_RAM);
- add_memory_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
- }
-
- printk(KERN_DEBUG "BIOS-provided physical RAM map:\n");
- e820_print_map(who);
-
- /* This also sets end_pfn_map */
- end_pfn = e820_end_of_ram();
-}
-
-void __init parse_memopt(char *p, char **from)
-{
- end_user_pfn = memparse(p, from);
- end_user_pfn >>= PAGE_SHIFT;
-}
-
-void __init parse_memmapopt(char *p, char **from)
-{
- unsigned long long start_at, mem_size;
-
- mem_size = memparse(p, from);
- p = *from;
- if (*p == '@') {
- start_at = memparse(p+1, from);
- add_memory_region(start_at, mem_size, E820_RAM);
- } else if (*p == '#') {
- start_at = memparse(p+1, from);
- add_memory_region(start_at, mem_size, E820_ACPI);
- } else if (*p == '$') {
- start_at = memparse(p+1, from);
- add_memory_region(start_at, mem_size, E820_RESERVED);
- } else {
- end_user_pfn = (mem_size >> PAGE_SHIFT);
- }
- p = *from;
-}
-
-unsigned long pci_mem_start = 0xaeedbabe;
-
-/*
- * Search for the biggest gap in the low 32 bits of the e820
- * memory space. We pass this space to PCI to assign MMIO resources
- * for hotplug or unconfigured devices in.
- * Hopefully the BIOS let enough space left.
- */
-__init void e820_setup_gap(void)
-{
- unsigned long gapstart, gapsize, round;
- unsigned long last;
- int i;
- int found = 0;
-
- last = 0x100000000ull;
- gapstart = 0x10000000;
- gapsize = 0x400000;
- i = e820.nr_map;
- while (--i >= 0) {
- unsigned long long start = e820.map[i].addr;
- unsigned long long end = start + e820.map[i].size;
-
- /*
- * Since "last" is at most 4GB, we know we'll
- * fit in 32 bits if this condition is true
- */
- if (last > end) {
- unsigned long gap = last - end;
-
- if (gap > gapsize) {
- gapsize = gap;
- gapstart = end;
- found = 1;
- }
- }
- if (start < last)
- last = start;
- }
-
- if (!found) {
- gapstart = (end_pfn << PAGE_SHIFT) + 1024*1024;
- printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit address range\n"
- KERN_ERR "PCI: Unassigned devices with 32bit resource registers may break!\n");
- }
-
- /*
- * See how much we want to round up: start off with
- * rounding to the next 1MB area.
- */
- round = 0x100000;
- while ((gapsize >> 4) > round)
- round += round;
- /* Fun with two's complement */
- pci_mem_start = (gapstart + round) & -round;
-
- printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
- pci_mem_start, gapstart, gapsize);
-}