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/*
* linux/arch/alpha/mm/init.c
*
* Copyright (C) 1995 Linus Torvalds
*/
#include <linux/config.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/head.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/hwrpb.h>
#include <asm/dma.h>
extern void die_if_kernel(char *,struct pt_regs *,long);
extern void show_net_buffers(void);
/*
* BAD_PAGE is the page that is used for page faults when linux
* is out-of-memory. Older versions of linux just did a
* do_exit(), but using this instead means there is less risk
* for a process dying in kernel mode, possibly leaving an inode
* unused etc..
*
* BAD_PAGETABLE is the accompanying page-table: it is initialized
* to point to BAD_PAGE entries.
*
* ZERO_PAGE is a special page that is used for zero-initialized
* data and COW.
*/
pmd_t * __bad_pagetable(void)
{
memset((void *) EMPTY_PGT, 0, PAGE_SIZE);
return (pmd_t *) EMPTY_PGT;
}
pte_t __bad_page(void)
{
memset((void *) EMPTY_PGE, 0, PAGE_SIZE);
return pte_mkdirty(mk_pte((unsigned long) EMPTY_PGE, PAGE_SHARED));
}
void show_mem(void)
{
int i,free = 0,total = 0,reserved = 0;
int shared = 0;
printk("\nMem-info:\n");
show_free_areas();
printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
i = max_mapnr;
while (i-- > 0) {
total++;
if (PageReserved(mem_map+i))
reserved++;
else if (!atomic_read(&mem_map[i].count))
free++;
else
shared += atomic_read(&mem_map[i].count) - 1;
}
printk("%d pages of RAM\n",total);
printk("%d free pages\n",free);
printk("%d reserved pages\n",reserved);
printk("%d pages shared\n",shared);
show_buffers();
#ifdef CONFIG_NET
show_net_buffers();
#endif
}
extern unsigned long free_area_init(unsigned long, unsigned long);
static void load_PCB(struct thread_struct * pcb)
{
__asm__ __volatile__(
"stq $30,0(%0)\n\t"
"bis %0,%0,$16\n\t"
"call_pal %1"
: /* no outputs */
: "r" (pcb), "i" (PAL_swpctx)
: "$0", "$1", "$16", "$22", "$23", "$24", "$25");
}
/*
* paging_init() sets up the page tables: in the alpha version this actually
* unmaps the bootup page table (as we're now in KSEG, so we don't need it).
*/
unsigned long paging_init(unsigned long start_mem, unsigned long end_mem)
{
int i;
unsigned long newptbr;
struct memclust_struct * cluster;
struct memdesc_struct * memdesc;
/* initialize mem_map[] */
start_mem = free_area_init(start_mem, end_mem);
/* find free clusters, update mem_map[] accordingly */
memdesc = (struct memdesc_struct *) (INIT_HWRPB->mddt_offset + (unsigned long) INIT_HWRPB);
cluster = memdesc->cluster;
for (i = memdesc->numclusters ; i > 0; i--, cluster++) {
unsigned long pfn, nr;
if (cluster->usage & 1)
continue;
pfn = cluster->start_pfn;
nr = cluster->numpages;
/* non-volatile memory. We might want to mark this for later */
if (cluster->usage & 2)
continue;
while (nr--)
clear_bit(PG_reserved, &mem_map[pfn++].flags);
}
/* unmap the console stuff: we don't need it, and we don't want it */
/* Also set up the real kernel PCB while we're at it.. */
memset((void *) ZERO_PAGE, 0, PAGE_SIZE);
memset(swapper_pg_dir, 0, PAGE_SIZE);
newptbr = ((unsigned long) swapper_pg_dir - PAGE_OFFSET) >> PAGE_SHIFT;
pgd_val(swapper_pg_dir[1023]) = (newptbr << 32) | pgprot_val(PAGE_KERNEL);
init_task.tss.ptbr = newptbr;
init_task.tss.pal_flags = 1; /* set FEN, clear everything else */
init_task.tss.flags = 0;
init_task.kernel_stack_page = INIT_STACK;
load_PCB(&init_task.tss);
flush_tlb_all();
return start_mem;
}
void mem_init(unsigned long start_mem, unsigned long end_mem)
{
unsigned long tmp;
end_mem &= PAGE_MASK;
max_mapnr = num_physpages = MAP_NR(end_mem);
high_memory = (void *) end_mem;
start_mem = PAGE_ALIGN(start_mem);
/*
* Mark the pages used by the kernel as reserved.
*/
tmp = KERNEL_START;
while (tmp < start_mem) {
set_bit(PG_reserved, &mem_map[MAP_NR(tmp)].flags);
tmp += PAGE_SIZE;
}
for (tmp = PAGE_OFFSET ; tmp < end_mem ; tmp += PAGE_SIZE) {
if (tmp >= MAX_DMA_ADDRESS)
clear_bit(PG_DMA, &mem_map[MAP_NR(tmp)].flags);
if (PageReserved(mem_map+MAP_NR(tmp)))
continue;
atomic_set(&mem_map[MAP_NR(tmp)].count, 1);
free_page(tmp);
}
tmp = nr_free_pages << PAGE_SHIFT;
printk("Memory: %luk available\n", tmp >> 10);
return;
}
void free_initmem (void)
{
extern char __init_begin, __init_end;
unsigned long addr;
addr = (unsigned long)(&__init_begin);
for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
mem_map[MAP_NR(addr)].flags &= ~(1 << PG_reserved);
atomic_set(&mem_map[MAP_NR(addr)].count, 1);
free_page(addr);
}
printk ("Freeing unused kernel memory: %dk freed\n",
(&__init_end - &__init_begin) >> 10);
}
void si_meminfo(struct sysinfo *val)
{
int i;
i = max_mapnr;
val->totalram = 0;
val->sharedram = 0;
val->freeram = nr_free_pages << PAGE_SHIFT;
val->bufferram = buffermem;
while (i-- > 0) {
if (PageReserved(mem_map+i))
continue;
val->totalram++;
if (!atomic_read(&mem_map[i].count))
continue;
val->sharedram += atomic_read(&mem_map[i].count) - 1;
}
val->totalram <<= PAGE_SHIFT;
val->sharedram <<= PAGE_SHIFT;
return;
}
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