ulong
umbrwmalloc(ulong addr, int size, int align)
{
ulong a;
uchar o[2], *p;
if(a = mapalloc(&rmapumbrw, addr, size, align))
return(ulong)KADDR(a);
/*
* Perhaps the memory wasn't visible before
* the interface is initialised, so try again.
*/
if((a = umbmalloc(addr, size, align)) == 0)
return 0;
p = (uchar*)a;
o[0] = p[0];
p[0] = 0xCC;
o[1] = p[size-1];
p[size-1] = 0xCC;
if(p[0] == 0xCC && p[size-1] == 0xCC){
p[0] = o[0];
p[size-1] = o[1];
return a;
}
umbfree(a, size);
return 0;
}
ulong
upamalloc(ulong addr, int size, int align)
{
ulong ae, a;
USED(align);
if((a = mapalloc(&rmapupa, addr, size, align)) == 0){
memdebug();
return 0;
}
/*
* This is a travesty, but they all are.
*/
ae = mmukmap(a, 0, size);
/*
* Should check here that it was all delivered
* and put it back and barf if not.
*/
USED(ae);
/*
* Be very careful this returns a PHYSICAL address.
*/
return a;
}
static void
umbexclude(void)
{
int size;
ulong addr;
char *op, *p, *rptr;
if((p = getconf("umbexclude")) == nil)
return;
while(p && *p != '\0' && *p != '\n'){
op = p;
addr = strtoul(p, &rptr, 0);
if(rptr == nil || rptr == p || *rptr != '-'){
print("umbexclude: invalid argument <%s>\n", op);
break;
}
p = rptr+1;
size = strtoul(p, &rptr, 0) - addr + 1;
if(size <= 0){
print("umbexclude: bad range <%s>\n", op);
break;
}
if(rptr != nil && *rptr == ',')
*rptr++ = '\0';
p = rptr;
mapalloc(&rmapumb, addr, size, 0);
}
}
ulong
umbmalloc(ulong addr, int size, int align)
{
ulong a;
if(a = mapalloc(&rmapumb, addr, size, align))
return (ulong)KADDR(a);
return 0;
}
uint32_t
umbmalloc(uint32_t addr, int size, int align)
{
uint32_t a;
if(a = mapalloc(&rmapumb, addr, size, align))
return (uint32_t)KADDR(a);
return 0;
}
/*
* Allocate from the ram map directly to make page tables.
* Called by mmuwalk during e820scan.
*/
void*
rampage(void)
{
ulong m;
m = mapalloc(&rmapram, 0, BY2PG, BY2PG);
if(m == 0)
return nil;
return KADDR(m);
}
BD *
bdalloc(int n)
{
ulong a;
a = mapalloc(&bdmap, 0, n*sizeof(BD), 0);
if(a == 0)
panic("bdalloc");
return KADDR(a);
}
/*
* Give out otherwise-unused physical address space
* for use in configuring devices. Note that unlike upamalloc
* before it, upaalloc does not map the physical address
* into virtual memory. Call vmap to do that.
*/
ulong
upaalloc(int size, int align)
{
ulong a;
a = mapalloc(&rmapupa, 0, size, align);
if(a == 0){
print("out of physical address space allocating %d\n", size);
mapprint(&rmapupa);
}
return a;
}
void
upareserve(ulong pa, int size)
{
ulong a;
a = mapalloc(&rmapupa, pa, size, 0);
if(a != pa){
/*
* This can happen when we're using the E820
* map, which might have already reserved some
* of the regions claimed by the pci devices.
*/
// print("upareserve: cannot reserve pa=%#.8lux size=%d\n", pa, size);
if(a != 0)
mapfree(&rmapupa, a, size);
}
}
uint32_t
umbrwmalloc(uint32_t addr, int size, int align)
{
uint32_t a;
uint8_t *p;
if(a = mapalloc(&rmapumbrw, addr, size, align))
return(uint32_t)KADDR(a);
/*
* Perhaps the memory wasn't visible before
* the interface is initialised, so try again.
*/
if((a = umbmalloc(addr, size, align)) == 0)
return 0;
p = (uint8_t*)a;
p[0] = 0xCC;
p[size-1] = 0xCC;
if(p[0] == 0xCC && p[size-1] == 0xCC)
return a;
umbfree(a, size);
return 0;
}
static void
ramscan(ulong maxmem)
{
ulong *k0, kzero, map, maxkpa, maxpa, pa, *pte, *table, *va, vbase, x;
int nvalid[NMemType];
/*
* The bootstrap code has has created a prototype page
* table which maps the first MemMin of physical memory to KZERO.
* The page directory is at m->pdb and the first page of
* free memory is after the per-processor MMU information.
*/
pa = MemMin;
/*
* Check if the extended memory size can be obtained from the CMOS.
* If it's 0 then it's either not known or >= 64MB. Always check
* at least 24MB in case there's a memory gap (up to 8MB) below 16MB;
* in this case the memory from the gap is remapped to the top of
* memory.
* The value in CMOS is supposed to be the number of KB above 1MB.
*/
if(maxmem == 0){
x = (nvramread(0x18)<<8)|nvramread(0x17);
if(x == 0 || x >= (63*KB))
maxpa = MemMax;
else
maxpa = MB+x*KB;
if(maxpa < 24*MB)
maxpa = 24*MB;
}else
maxpa = maxmem;
maxkpa = (u32int)-KZERO; /* 2^32 - KZERO */
/*
* March up memory from MemMin to maxpa 1MB at a time,
* mapping the first page and checking the page can
* be written and read correctly. The page tables are created here
* on the fly, allocating from low memory as necessary.
*/
k0 = (ulong*)KADDR(0);
kzero = *k0;
map = 0;
x = 0x12345678;
memset(nvalid, 0, sizeof(nvalid));
/*
* Can't map memory to KADDR(pa) when we're walking because
* can only use KADDR for relatively low addresses.
* Instead, map each 4MB we scan to the virtual address range
* MemMin->MemMin+4MB while we are scanning.
*/
vbase = MemMin;
while(pa < maxpa){
/*
* Map the page. Use mapalloc(&rmapram, ...) to make
* the page table if necessary, it will be returned to the
* pool later if it isn't needed. Map in a fixed range (the second 4M)
* because high physical addresses cannot be passed to KADDR.
*/
va = (void*)(vbase + pa%(4*MB));
table = &m->pdb[PDX(va)];
if(pa%(4*MB) == 0){
if(map == 0 && (map = mapalloc(&rmapram, 0, BY2PG, BY2PG)) == 0)
break;
memset(KADDR(map), 0, BY2PG);
*table = map|PTEWRITE|PTEVALID;
memset(nvalid, 0, sizeof(nvalid));
}
table = KADDR(PPN(*table));
pte = &table[PTX(va)];
*pte = pa|PTEWRITE|PTEUNCACHED|PTEVALID;
mmuflushtlb(PADDR(m->pdb));
/*
* Write a pattern to the page and write a different
* pattern to a possible mirror at KZERO. If the data
* reads back correctly the chunk is some type of RAM (possibly
* a linearly-mapped VGA framebuffer, for instance...) and
* can be cleared and added to the memory pool. If not, the
* chunk is marked uncached and added to the UMB pool if <16MB
* or is marked invalid and added to the UPA pool.
*/
*va = x;
*k0 = ~x;
if(*va == x){
nvalid[MemRAM] += MB/BY2PG;
mapfree(&rmapram, pa, MB);
do{
*pte++ = pa|PTEWRITE|PTEVALID;
pa += BY2PG;
}while(pa % MB);
mmuflushtlb(PADDR(m->pdb));
/* memset(va, 0, MB); so damn slow to memset all of memory */
}
else if(pa < 16*MB){
nvalid[MemUMB] += MB/BY2PG;
mapfree(&rmapumb, pa, MB);
do{
*pte++ = pa|PTEWRITE|PTEUNCACHED|PTEVALID;
pa += BY2PG;
}while(pa % MB);
}
else{
nvalid[MemUPA] += MB/BY2PG;
mapfree(&rmapupa, pa, MB);
*pte = 0;
pa += MB;
}
/*
* Done with this 4MB chunk, review the options:
* 1) not physical memory and >=16MB - invalidate the PDB entry;
* 2) physical memory - use the 4MB page extension if possible;
* 3) not physical memory and <16MB - use the 4MB page extension
* if possible;
* 4) mixed or no 4MB page extension - commit the already
* initialised space for the page table.
*/
if(pa%(4*MB) == 0 && pa >= 32*MB && nvalid[MemUPA] == (4*MB)/BY2PG){
/*
* If we encounter a 4MB chunk of missing memory
* at a sufficiently high offset, call it the end of
* memory. Otherwise we run the risk of thinking
* that video memory is real RAM.
*/
break;
}
if(pa <= maxkpa && pa%(4*MB) == 0){
table = &m->pdb[PDX(KADDR(pa - 4*MB))];
if(nvalid[MemUPA] == (4*MB)/BY2PG)
*table = 0;
else if(nvalid[MemRAM] == (4*MB)/BY2PG && (m->cpuiddx & 0x08))
*table = (pa - 4*MB)|PTESIZE|PTEWRITE|PTEVALID;
else if(nvalid[MemUMB] == (4*MB)/BY2PG && (m->cpuiddx & 0x08))
*table = (pa - 4*MB)|PTESIZE|PTEWRITE|PTEUNCACHED|PTEVALID;
else{
*table = map|PTEWRITE|PTEVALID;
map = 0;
}
}
mmuflushtlb(PADDR(m->pdb));
x += 0x3141526;
}
/*
* If we didn't reach the end of the 4MB chunk, that part won't
* be mapped. Commit the already initialised space for the page table.
*/
if(pa % (4*MB) && pa <= maxkpa){
m->pdb[PDX(KADDR(pa))] = map|PTEWRITE|PTEVALID;
map = 0;
}
if(map)
mapfree(&rmapram, map, BY2PG);
m->pdb[PDX(vbase)] = 0;
mmuflushtlb(PADDR(m->pdb));
mapfree(&rmapupa, pa, (u32int)-pa);
*k0 = kzero;
}
