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Ignore whitespace Rev 1214 → Rev 1215

/kernel/trunk/arch/ppc32/src/mm/tlb.c
0,0 → 1,155
/*
* Copyright (C) 2006 Martin Decky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
#include <arch/mm/tlb.h>
#include <arch/types.h>
#include <mm/tlb.h>
#include <mm/page.h>
#include <mm/as.h>
#include <arch.h>
#include <print.h>
#include <symtab.h>
 
 
/** Initialize Page Hash Table.
*
* Setup the Page Hash Table with no entries.
*
*/
void tlb_arch_init(void)
{
}
 
 
/** Try to find PTE for faulting address
*
* Try to find PTE for faulting address.
* The AS->lock must be held on entry to this function.
*
* @param badvaddr Faulting virtual address.
* @return PTE on success, NULL otherwise.
*
*/
static pte_t *find_mapping_and_check(__address badvaddr)
{
/*
* Check if the mapping exists in page tables.
*/
pte_t *pte = page_mapping_find(AS, badvaddr);
if ((pte) && (pte->p)) {
/*
* Mapping found in page tables.
* Immediately succeed.
*/
return pte;
} else {
/*
* Mapping not found in page tables.
* Resort to higher-level page fault handler.
*/
page_table_unlock(AS, true);
if (as_page_fault(badvaddr)) {
/*
* The higher-level page fault handler succeeded,
* The mapping ought to be in place.
*/
page_table_lock(AS, true);
pte = page_mapping_find(AS, badvaddr);
ASSERT((pte) && (pte->p));
return pte;
} else {
page_table_lock(AS, true);
printf("Page fault.\n");
return NULL;
}
}
}
 
 
static void pht_refill_fail(__address badvaddr, istate_t *istate)
{
char *symbol = "";
char *sym2 = "";
 
char *s = get_symtab_entry(istate->pc);
if (s)
symbol = s;
s = get_symtab_entry(istate->lr);
if (s)
sym2 = s;
panic("%X: PHT Refill Exception at %X(%s<-%s)\n", badvaddr, istate->pc, symbol, sym2);
}
 
 
/** Process Data Storage Interrupt
*
* @param istate Interrupted register context.
*
*/
void pht_refill(istate_t *istate)
{
asid_t asid;
__address badvaddr;
pte_t *pte;
__asm__ volatile (
"mfdar %0\n"
: "=r" (badvaddr)
);
spinlock_lock(&AS->lock);
asid = AS->asid;
spinlock_unlock(&AS->lock);
page_table_lock(AS, true);
pte = find_mapping_and_check(badvaddr);
if (!pte)
goto fail;
 
/*
* Record access to PTE.
*/
pte->a = 1;
// FIXME: Insert entry into PHT
 
page_table_unlock(AS, true);
return;
fail:
page_table_unlock(AS, true);
pht_refill_fail(badvaddr, istate);
}
 
 
/** Print contents of Page Hash Table. */
void tlb_print(void)
{
}