WebSVN – HelenOS – Diff – /kernel/trunk/arch/mips32/src/mm/tlb.c


/*
 * Copyright (C) 2003-2004 Jakub Jermar
 * 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 <mm/asid.h>
#include <mm/tlb.h>
#include <mm/page.h>
#include <mm/as.h>
#include <arch/cp0.h>
#include <panic.h>
#include <arch.h>
#include <symtab.h>
#include <synch/spinlock.h>
#include <print.h>
#include <debug.h>
#include <align.h>
 
static void tlb_refill_fail(istate_t *istate);
static void tlb_invalid_fail(istate_t *istate);
static void tlb_modified_fail(istate_t *istate);
 
static pte_t *find_mapping_and_check(__address badvaddr, istate_t *istate, int *pfrc);
 
static void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn);
static void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr);
 
/** Initialize TLB
 *
 * Initialize TLB.
 * Invalidate all entries and mark wired entries.
 */
void tlb_arch_init(void)
{
    int i;
 
    cp0_pagemask_write(TLB_PAGE_MASK_16K);
    cp0_entry_hi_write(0);
    cp0_entry_lo0_write(0);
    cp0_entry_lo1_write(0);
 
    /* Clear and initialize TLB. */
   
    for (i = 0; i < TLB_ENTRY_COUNT; i++) {
        cp0_index_write(i);
        tlbwi();
    }
 
       
    /*
     * The kernel is going to make use of some wired
     * entries (e.g. mapping kernel stacks in kseg3).
     */
    cp0_wired_write(TLB_WIRED);
}
 
/** Process TLB Refill Exception
 *
 * Process TLB Refill Exception.
 *
 * @param istate Interrupted register context.
 */
void tlb_refill(istate_t *istate)
{
    entry_lo_t lo;
    entry_hi_t hi;
    asid_t asid;
    __address badvaddr;
    pte_t *pte;
    int pfrc;
 
    badvaddr = cp0_badvaddr_read();
 
    spinlock_lock(&AS->lock);
    asid = AS->asid;
    spinlock_unlock(&AS->lock);
 
    page_table_lock(AS, true);
 
    pte = find_mapping_and_check(badvaddr, istate, &pfrc);
    if (!pte) {
        switch (pfrc) {
        case AS_PF_FAULT:
            goto fail;
            break;
        case AS_PF_DEFER:
            /*
             * The page fault came during copy_from_uspace()
             * or copy_to_uspace().
             */
            page_table_unlock(AS, true);
            return;
        default:
            panic("unexpected pfrc (%d)\n", pfrc);
        }
    }
 
    /*
     * Record access to PTE.
     */
    pte->a = 1;
 
    prepare_entry_hi(&hi, asid, badvaddr);
    prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);
 
    /*
     * New entry is to be inserted into TLB
     */
    cp0_entry_hi_write(hi.value);
    if ((badvaddr/PAGE_SIZE) % 2 == 0) {
        cp0_entry_lo0_write(lo.value);
        cp0_entry_lo1_write(0);
    }
    else {
        cp0_entry_lo0_write(0);
        cp0_entry_lo1_write(lo.value);
    }
    cp0_pagemask_write(TLB_PAGE_MASK_16K);
    tlbwr();
 
    page_table_unlock(AS, true);
    return;
   
fail:
    page_table_unlock(AS, true);
    tlb_refill_fail(istate);
}
 
/** Process TLB Invalid Exception
 *
 * Process TLB Invalid Exception.
 *
 * @param istate Interrupted register context.
 */
void tlb_invalid(istate_t *istate)
{
    tlb_index_t index;
    __address badvaddr;
    entry_lo_t lo;
    entry_hi_t hi;
    pte_t *pte;
    int pfrc;
 
    badvaddr = cp0_badvaddr_read();
 
    /*
     * Locate the faulting entry in TLB.
     */
    hi.value = cp0_entry_hi_read();
    prepare_entry_hi(&hi, hi.asid, badvaddr);
    cp0_entry_hi_write(hi.value);
    tlbp();
    index.value = cp0_index_read();
 
    page_table_lock(AS, true); 
   
    /*
     * Fail if the entry is not in TLB.
     */
    if (index.p) {
        printf("TLB entry not found.\n");
        goto fail;
    }
 
    pte = find_mapping_and_check(badvaddr, istate, &pfrc);
    if (!pte) {
        switch (pfrc) {
        case AS_PF_FAULT:
            goto fail;
            break;
        case AS_PF_DEFER:
            /*
             * The page fault came during copy_from_uspace()
             * or copy_to_uspace().
             */
            page_table_unlock(AS, true);             
            return;
        default:
            panic("unexpected pfrc (%d)\n", pfrc);
        }
    }
 
    /*
     * Read the faulting TLB entry.
     */
    tlbr();
 
    /*
     * Record access to PTE.
     */
    pte->a = 1;
 
    prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);
 
    /*
     * The entry is to be updated in TLB.
     */
    if ((badvaddr/PAGE_SIZE) % 2 == 0)
        cp0_entry_lo0_write(lo.value);
    else
        cp0_entry_lo1_write(lo.value);
    cp0_pagemask_write(TLB_PAGE_MASK_16K);
    tlbwi();
 
    page_table_unlock(AS, true);
    return;
   
fail:
    page_table_unlock(AS, true);
    tlb_invalid_fail(istate);
}
 
/** Process TLB Modified Exception
 *
 * Process TLB Modified Exception.
 *
 * @param istate Interrupted register context.
 */
void tlb_modified(istate_t *istate)
{
    tlb_index_t index;
    __address badvaddr;
    entry_lo_t lo;
    entry_hi_t hi;
    pte_t *pte;
    int pfrc;
 
    badvaddr = cp0_badvaddr_read();
 
    /*
     * Locate the faulting entry in TLB.
     */
    hi.value = cp0_entry_hi_read();
    prepare_entry_hi(&hi, hi.asid, badvaddr);
    cp0_entry_hi_write(hi.value);
    tlbp();
    index.value = cp0_index_read();
 
    page_table_lock(AS, true); 
   
    /*
     * Fail if the entry is not in TLB.
     */
    if (index.p) {
        printf("TLB entry not found.\n");
        goto fail;
    }
 
    pte = find_mapping_and_check(badvaddr, istate, &pfrc);
    if (!pte) {
        switch (pfrc) {
        case AS_PF_FAULT:
            goto fail;
            break;
        case AS_PF_DEFER:
            /*
             * The page fault came during copy_from_uspace()
             * or copy_to_uspace().
             */
            page_table_unlock(AS, true);             
            return;
        default:
            panic("unexpected pfrc (%d)\n", pfrc);
        }
    }
 
    /*
     * Fail if the page is not writable.
     */
    if (!pte->w)
        goto fail;
 
    /*
     * Read the faulting TLB entry.
     */
    tlbr();
 
    /*
     * Record access and write to PTE.
     */
    pte->a = 1;
    pte->d = 1;
 
    prepare_entry_lo(&lo, pte->g, pte->p, pte->w, pte->cacheable, pte->pfn);
 
    /*
     * The entry is to be updated in TLB.
     */
    if ((badvaddr/PAGE_SIZE) % 2 == 0)
        cp0_entry_lo0_write(lo.value);
    else
        cp0_entry_lo1_write(lo.value);
    cp0_pagemask_write(TLB_PAGE_MASK_16K);
    tlbwi();
 
    page_table_unlock(AS, true);
    return;
   
fail:
    page_table_unlock(AS, true);
    tlb_modified_fail(istate);
}
 
void tlb_refill_fail(istate_t *istate)
{
    char *symbol = "";
    char *sym2 = "";
 
    char *s = get_symtab_entry(istate->epc);
    if (s)
        symbol = s;
    s = get_symtab_entry(istate->ra);
    if (s)
        sym2 = s;
    panic("%X: TLB Refill Exception at %X(%s<-%s)\n", cp0_badvaddr_read(), istate->epc, symbol, sym2);
}
 
 
void tlb_invalid_fail(istate_t *istate)
{
    char *symbol = "";
 
    char *s = get_symtab_entry(istate->epc);
    if (s)
        symbol = s;
    panic("%X: TLB Invalid Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);
}
 
void tlb_modified_fail(istate_t *istate)
{
    char *symbol = "";
 
    char *s = get_symtab_entry(istate->epc);
    if (s)
        symbol = s;
    panic("%X: TLB Modified Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);
}
 
/** 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.
 * @param istate Pointer to interrupted state.
 * @param pfrc Pointer to variable where as_page_fault() return code will be stored.
 *
 * @return PTE on success, NULL otherwise.
 */
pte_t *find_mapping_and_check(__address badvaddr, istate_t *istate, int *pfrc)
{
    entry_hi_t hi;
    pte_t *pte;
 
    hi.value = cp0_entry_hi_read();
 
    /*
     * Handler cannot succeed if the ASIDs don't match.
     */
    if (hi.asid != AS->asid) {
        printf("EntryHi.asid=%d, AS->asid=%d\n", hi.asid, AS->asid);
        return NULL;
    }
 
    /*
     * Check if the mapping exists in page tables.
     */
    pte = page_mapping_find(AS, badvaddr);
    if (pte && pte->p) {
        /*
         * Mapping found in page tables.
         * Immediately succeed.
         */
        return pte;
    } else {
        int rc;
       
        /*
         * Mapping not found in page tables.
         * Resort to higher-level page fault handler.
         */
        page_table_unlock(AS, true);
        switch (rc = as_page_fault(badvaddr, istate)) {
        case AS_PF_OK:
            /*
             * 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;
            break;
        case AS_PF_DEFER:
            page_table_lock(AS, true);
            *pfrc = AS_PF_DEFER;
            return NULL;
            break;
        case AS_PF_FAULT:
            page_table_lock(AS, true);
            printf("Page fault.\n");
            *pfrc = AS_PF_FAULT;
            return NULL;
            break;
        default:
            panic("unexpected rc (%d)\n", rc);
        }
       
    }
}
 
void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn)
{
    lo->value = 0;
    lo->g = g;
    lo->v = v;
    lo->d = d;
    lo->c = cacheable ? PAGE_CACHEABLE_EXC_WRITE : PAGE_UNCACHED;
    lo->pfn = pfn;
}
 
void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr)
{
    hi->value = ALIGN_DOWN(addr, PAGE_SIZE * 2);
    hi->asid = asid;
}
 
/** Print contents of TLB. */
void tlb_print(void)
{
    page_mask_t mask;
    entry_lo_t lo0, lo1;
    entry_hi_t hi, hi_save;
    int i;
 
    hi_save.value = cp0_entry_hi_read();
 
    printf("TLB:\n");
    for (i = 0; i < TLB_ENTRY_COUNT; i++) {
        cp0_index_write(i);
        tlbr();
       
        mask.value = cp0_pagemask_read();
        hi.value = cp0_entry_hi_read();
        lo0.value = cp0_entry_lo0_read();
        lo1.value = cp0_entry_lo1_read();
       
        printf("%d: asid=%d, vpn2=%d, mask=%d\tg[0]=%d, v[0]=%d, d[0]=%d, c[0]=%hhd, pfn[0]=%d\n"
               "\t\t\t\tg[1]=%d, v[1]=%d, d[1]=%d, c[1]=%hhd, pfn[1]=%d\n",
               i, hi.asid, hi.vpn2, mask.mask, lo0.g, lo0.v, lo0.d, lo0.c, lo0.pfn,
               lo1.g, lo1.v, lo1.d, lo1.c, lo1.pfn);
    }
   
    cp0_entry_hi_write(hi_save.value);
}
 
/** Invalidate all not wired TLB entries. */
void tlb_invalidate_all(void)
{
    ipl_t ipl;
    entry_lo_t lo0, lo1;
    entry_hi_t hi_save;
    int i;
 
    hi_save.value = cp0_entry_hi_read();
    ipl = interrupts_disable();
 
    for (i = TLB_WIRED; i < TLB_ENTRY_COUNT; i++) {
        cp0_index_write(i);
        tlbr();
 
        lo0.value = cp0_entry_lo0_read();
        lo1.value = cp0_entry_lo1_read();
 
        lo0.v = 0;
        lo1.v = 0;
 
        cp0_entry_lo0_write(lo0.value);
        cp0_entry_lo1_write(lo1.value);
               
        tlbwi();
    }
   
    interrupts_restore(ipl);
    cp0_entry_hi_write(hi_save.value);
}
 
/** Invalidate all TLB entries belonging to specified address space.
 *
 * @param asid Address space identifier.
 */
void tlb_invalidate_asid(asid_t asid)
{
    ipl_t ipl;
    entry_lo_t lo0, lo1;
    entry_hi_t hi, hi_save;
    int i;
 
    ASSERT(asid != ASID_INVALID);
 
    hi_save.value = cp0_entry_hi_read();
    ipl = interrupts_disable();
   
    for (i = 0; i < TLB_ENTRY_COUNT; i++) {
        cp0_index_write(i);
        tlbr();
       
        hi.value = cp0_entry_hi_read();
       
        if (hi.asid == asid) {
            lo0.value = cp0_entry_lo0_read();
            lo1.value = cp0_entry_lo1_read();
 
            lo0.v = 0;
            lo1.v = 0;
 
            cp0_entry_lo0_write(lo0.value);
            cp0_entry_lo1_write(lo1.value);
 
            tlbwi();
        }
    }
   
    interrupts_restore(ipl);
    cp0_entry_hi_write(hi_save.value);
}
 
/** Invalidate TLB entries for specified page range belonging to specified address space.
 *
 * @param asid Address space identifier.
 * @param page First page whose TLB entry is to be invalidated.
 * @param cnt Number of entries to invalidate.
 */
void tlb_invalidate_pages(asid_t asid, __address page, count_t cnt)
{
    int i;
    ipl_t ipl;
    entry_lo_t lo0, lo1;
    entry_hi_t hi, hi_save;
    tlb_index_t index;
 
    ASSERT(asid != ASID_INVALID);
 
    hi_save.value = cp0_entry_hi_read();
    ipl = interrupts_disable();
 
    for (i = 0; i < cnt+1; i+=2) {
        hi.value = 0;
        prepare_entry_hi(&hi, asid, page + i * PAGE_SIZE);
        cp0_entry_hi_write(hi.value);
 
        tlbp();
        index.value = cp0_index_read();
 
        if (!index.p) {
            /* Entry was found, index register contains valid index. */
            tlbr();
 
            lo0.value = cp0_entry_lo0_read();
            lo1.value = cp0_entry_lo1_read();
 
            lo0.v = 0;
            lo1.v = 0;
 
            cp0_entry_lo0_write(lo0.value);
            cp0_entry_lo1_write(lo1.value);
 
            tlbwi();
        }
    }
   
    interrupts_restore(ipl);
    cp0_entry_hi_write(hi_save.value);
}
 

Rev 1196	Rev 1288
1	/*	1	/*
2	* Copyright (C) 2003-2004 Jakub Jermar	2	* Copyright (C) 2003-2004 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	#include <arch/mm/tlb.h>	29	#include <arch/mm/tlb.h>
30	#include <mm/asid.h>	30	#include <mm/asid.h>
31	#include <mm/tlb.h>	31	#include <mm/tlb.h>
32	#include <mm/page.h>	32	#include <mm/page.h>
33	#include <mm/as.h>	33	#include <mm/as.h>
34	#include <arch/cp0.h>	34	#include <arch/cp0.h>
35	#include <panic.h>	35	#include <panic.h>
36	#include <arch.h>	36	#include <arch.h>
37	#include <symtab.h>	37	#include <symtab.h>
38	#include <synch/spinlock.h>	38	#include <synch/spinlock.h>
39	#include <print.h>	39	#include <print.h>
40	#include <debug.h>	40	#include <debug.h>
41	#include <align.h>	41	#include <align.h>
42		42
43	static void tlb_refill_fail(istate_t *istate);	43	static void tlb_refill_fail(istate_t *istate);
44	static void tlb_invalid_fail(istate_t *istate);	44	static void tlb_invalid_fail(istate_t *istate);
45	static void tlb_modified_fail(istate_t *istate);	45	static void tlb_modified_fail(istate_t *istate);
46		46
47	static pte_t *find_mapping_and_check(__address badvaddr);	47	static pte_t find_mapping_and_check(__address badvaddr, istate_t istate, int *pfrc);
48		48
49	static void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn);	49	static void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn);
50	static void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr);	50	static void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr);
51		51
52	/** Initialize TLB	52	/** Initialize TLB
53	*	53	*
54	* Initialize TLB.	54	* Initialize TLB.
55	* Invalidate all entries and mark wired entries.	55	* Invalidate all entries and mark wired entries.
56	*/	56	*/
57	void tlb_arch_init(void)	57	void tlb_arch_init(void)
58	{	58	{
59	int i;	59	int i;
60		60
61	cp0_pagemask_write(TLB_PAGE_MASK_16K);	61	cp0_pagemask_write(TLB_PAGE_MASK_16K);
62	cp0_entry_hi_write(0);	62	cp0_entry_hi_write(0);
63	cp0_entry_lo0_write(0);	63	cp0_entry_lo0_write(0);
64	cp0_entry_lo1_write(0);	64	cp0_entry_lo1_write(0);
65		65
66	/* Clear and initialize TLB. */	66	/* Clear and initialize TLB. */
67		67
68	for (i = 0; i < TLB_ENTRY_COUNT; i++) {	68	for (i = 0; i < TLB_ENTRY_COUNT; i++) {
69	cp0_index_write(i);	69	cp0_index_write(i);
70	tlbwi();	70	tlbwi();
71	}	71	}
72		72
73		73
74	/*	74	/*
75	* The kernel is going to make use of some wired	75	* The kernel is going to make use of some wired
76	* entries (e.g. mapping kernel stacks in kseg3).	76	* entries (e.g. mapping kernel stacks in kseg3).
77	*/	77	*/
78	cp0_wired_write(TLB_WIRED);	78	cp0_wired_write(TLB_WIRED);
79	}	79	}
80		80
81	/** Process TLB Refill Exception	81	/** Process TLB Refill Exception
82	*	82	*
83	* Process TLB Refill Exception.	83	* Process TLB Refill Exception.
84	*	84	*
85	* @param istate Interrupted register context.	85	* @param istate Interrupted register context.
86	*/	86	*/
87	void tlb_refill(istate_t *istate)	87	void tlb_refill(istate_t *istate)
88	{	88	{
89	entry_lo_t lo;	89	entry_lo_t lo;
90	entry_hi_t hi;	90	entry_hi_t hi;
91	asid_t asid;	91	asid_t asid;
92	__address badvaddr;	92	__address badvaddr;
93	pte_t *pte;	93	pte_t *pte;
-		94	int pfrc;
94		95
95	badvaddr = cp0_badvaddr_read();	96	badvaddr = cp0_badvaddr_read();
96		97
97	spinlock_lock(&AS->lock);	98	spinlock_lock(&AS->lock);
98	asid = AS->asid;	99	asid = AS->asid;
99	spinlock_unlock(&AS->lock);	100	spinlock_unlock(&AS->lock);
100		101
101	page_table_lock(AS, true);	102	page_table_lock(AS, true);
102		103
103	pte = find_mapping_and_check(badvaddr);	104	pte = find_mapping_and_check(badvaddr, istate, &pfrc);
104	if (!pte)	105	if (!pte) {
-		106	switch (pfrc) {
-		107	case AS_PF_FAULT:
105	goto fail;	108	goto fail;
-		109	break;
-		110	case AS_PF_DEFER:
-		111	/*
-		112	* The page fault came during copy_from_uspace()
-		113	* or copy_to_uspace().
-		114	*/
-		115	page_table_unlock(AS, true);
-		116	return;
-		117	default:
-		118	panic("unexpected pfrc (%d)\n", pfrc);
-		119	}
-		120	}
106		121
107	/*	122	/*
108	* Record access to PTE.	123	* Record access to PTE.
109	*/	124	*/
110	pte->a = 1;	125	pte->a = 1;
111		126
112	prepare_entry_hi(&hi, asid, badvaddr);	127	prepare_entry_hi(&hi, asid, badvaddr);
113	prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);	128	prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);
114		129
115	/*	130	/*
116	* New entry is to be inserted into TLB	131	* New entry is to be inserted into TLB
117	*/	132	*/
118	cp0_entry_hi_write(hi.value);	133	cp0_entry_hi_write(hi.value);
119	if ((badvaddr/PAGE_SIZE) % 2 == 0) {	134	if ((badvaddr/PAGE_SIZE) % 2 == 0) {
120	cp0_entry_lo0_write(lo.value);	135	cp0_entry_lo0_write(lo.value);
121	cp0_entry_lo1_write(0);	136	cp0_entry_lo1_write(0);
122	}	137	}
123	else {	138	else {
124	cp0_entry_lo0_write(0);	139	cp0_entry_lo0_write(0);
125	cp0_entry_lo1_write(lo.value);	140	cp0_entry_lo1_write(lo.value);
126	}	141	}
127	cp0_pagemask_write(TLB_PAGE_MASK_16K);	142	cp0_pagemask_write(TLB_PAGE_MASK_16K);
128	tlbwr();	143	tlbwr();
129		144
130	page_table_unlock(AS, true);	145	page_table_unlock(AS, true);
131	return;	146	return;
132		147
133	fail:	148	fail:
134	page_table_unlock(AS, true);	149	page_table_unlock(AS, true);
135	tlb_refill_fail(istate);	150	tlb_refill_fail(istate);
136	}	151	}
137		152
138	/** Process TLB Invalid Exception	153	/** Process TLB Invalid Exception
139	*	154	*
140	* Process TLB Invalid Exception.	155	* Process TLB Invalid Exception.
141	*	156	*
142	* @param istate Interrupted register context.	157	* @param istate Interrupted register context.
143	*/	158	*/
144	void tlb_invalid(istate_t *istate)	159	void tlb_invalid(istate_t *istate)
145	{	160	{
146	tlb_index_t index;	161	tlb_index_t index;
147	__address badvaddr;	162	__address badvaddr;
148	entry_lo_t lo;	163	entry_lo_t lo;
149	entry_hi_t hi;	164	entry_hi_t hi;
150	pte_t *pte;	165	pte_t *pte;
-		166	int pfrc;
151		167
152	badvaddr = cp0_badvaddr_read();	168	badvaddr = cp0_badvaddr_read();
153		169
154	/*	170	/*
155	* Locate the faulting entry in TLB.	171	* Locate the faulting entry in TLB.
156	*/	172	*/
157	hi.value = cp0_entry_hi_read();	173	hi.value = cp0_entry_hi_read();
158	prepare_entry_hi(&hi, hi.asid, badvaddr);	174	prepare_entry_hi(&hi, hi.asid, badvaddr);
159	cp0_entry_hi_write(hi.value);	175	cp0_entry_hi_write(hi.value);
160	tlbp();	176	tlbp();
161	index.value = cp0_index_read();	177	index.value = cp0_index_read();
162		178
163	page_table_lock(AS, true);	179	page_table_lock(AS, true);
164		180
165	/*	181	/*
166	* Fail if the entry is not in TLB.	182	* Fail if the entry is not in TLB.
167	*/	183	*/
168	if (index.p) {	184	if (index.p) {
169	printf("TLB entry not found.\n");	185	printf("TLB entry not found.\n");
170	goto fail;	186	goto fail;
171	}	187	}
172		188
173	pte = find_mapping_and_check(badvaddr);	189	pte = find_mapping_and_check(badvaddr, istate, &pfrc);
174	if (!pte)	190	if (!pte) {
-		191	switch (pfrc) {
-		192	case AS_PF_FAULT:
175	goto fail;	193	goto fail;
-		194	break;
-		195	case AS_PF_DEFER:
-		196	/*
-		197	* The page fault came during copy_from_uspace()
-		198	* or copy_to_uspace().
-		199	*/
-		200	page_table_unlock(AS, true);
-		201	return;
-		202	default:
-		203	panic("unexpected pfrc (%d)\n", pfrc);
-		204	}
-		205	}
176		206
177	/*	207	/*
178	* Read the faulting TLB entry.	208	* Read the faulting TLB entry.
179	*/	209	*/
180	tlbr();	210	tlbr();
181		211
182	/*	212	/*
183	* Record access to PTE.	213	* Record access to PTE.
184	*/	214	*/
185	pte->a = 1;	215	pte->a = 1;
186		216
187	prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);	217	prepare_entry_lo(&lo, pte->g, pte->p, pte->d, pte->cacheable, pte->pfn);
188		218
189	/*	219	/*
190	* The entry is to be updated in TLB.	220	* The entry is to be updated in TLB.
191	*/	221	*/
192	if ((badvaddr/PAGE_SIZE) % 2 == 0)	222	if ((badvaddr/PAGE_SIZE) % 2 == 0)
193	cp0_entry_lo0_write(lo.value);	223	cp0_entry_lo0_write(lo.value);
194	else	224	else
195	cp0_entry_lo1_write(lo.value);	225	cp0_entry_lo1_write(lo.value);
196	cp0_pagemask_write(TLB_PAGE_MASK_16K);	226	cp0_pagemask_write(TLB_PAGE_MASK_16K);
197	tlbwi();	227	tlbwi();
198		228
199	page_table_unlock(AS, true);	229	page_table_unlock(AS, true);
200	return;	230	return;
201		231
202	fail:	232	fail:
203	page_table_unlock(AS, true);	233	page_table_unlock(AS, true);
204	tlb_invalid_fail(istate);	234	tlb_invalid_fail(istate);
205	}	235	}
206		236
207	/** Process TLB Modified Exception	237	/** Process TLB Modified Exception
208	*	238	*
209	* Process TLB Modified Exception.	239	* Process TLB Modified Exception.
210	*	240	*
211	* @param istate Interrupted register context.	241	* @param istate Interrupted register context.
212	*/	242	*/
213	void tlb_modified(istate_t *istate)	243	void tlb_modified(istate_t *istate)
214	{	244	{
215	tlb_index_t index;	245	tlb_index_t index;
216	__address badvaddr;	246	__address badvaddr;
217	entry_lo_t lo;	247	entry_lo_t lo;
218	entry_hi_t hi;	248	entry_hi_t hi;
219	pte_t *pte;	249	pte_t *pte;
-		250	int pfrc;
220		251
221	badvaddr = cp0_badvaddr_read();	252	badvaddr = cp0_badvaddr_read();
222		253
223	/*	254	/*
224	* Locate the faulting entry in TLB.	255	* Locate the faulting entry in TLB.
225	*/	256	*/
226	hi.value = cp0_entry_hi_read();	257	hi.value = cp0_entry_hi_read();
227	prepare_entry_hi(&hi, hi.asid, badvaddr);	258	prepare_entry_hi(&hi, hi.asid, badvaddr);
228	cp0_entry_hi_write(hi.value);	259	cp0_entry_hi_write(hi.value);
229	tlbp();	260	tlbp();
230	index.value = cp0_index_read();	261	index.value = cp0_index_read();
231		262
232	page_table_lock(AS, true);	263	page_table_lock(AS, true);
233		264
234	/*	265	/*
235	* Fail if the entry is not in TLB.	266	* Fail if the entry is not in TLB.
236	*/	267	*/
237	if (index.p) {	268	if (index.p) {
238	printf("TLB entry not found.\n");	269	printf("TLB entry not found.\n");
239	goto fail;	270	goto fail;
240	}	271	}
241		272
242	pte = find_mapping_and_check(badvaddr);	273	pte = find_mapping_and_check(badvaddr, istate, &pfrc);
243	if (!pte)	274	if (!pte) {
-		275	switch (pfrc) {
-		276	case AS_PF_FAULT:
244	goto fail;	277	goto fail;
-		278	break;
-		279	case AS_PF_DEFER:
-		280	/*
-		281	* The page fault came during copy_from_uspace()
-		282	* or copy_to_uspace().
-		283	*/
-		284	page_table_unlock(AS, true);
-		285	return;
-		286	default:
-		287	panic("unexpected pfrc (%d)\n", pfrc);
-		288	}
-		289	}
245		290
246	/*	291	/*
247	* Fail if the page is not writable.	292	* Fail if the page is not writable.
248	*/	293	*/
249	if (!pte->w)	294	if (!pte->w)
250	goto fail;	295	goto fail;
251		296
252	/*	297	/*
253	* Read the faulting TLB entry.	298	* Read the faulting TLB entry.
254	*/	299	*/
255	tlbr();	300	tlbr();
256		301
257	/*	302	/*
258	* Record access and write to PTE.	303	* Record access and write to PTE.
259	*/	304	*/
260	pte->a = 1;	305	pte->a = 1;
261	pte->d = 1;	306	pte->d = 1;
262		307
263	prepare_entry_lo(&lo, pte->g, pte->p, pte->w, pte->cacheable, pte->pfn);	308	prepare_entry_lo(&lo, pte->g, pte->p, pte->w, pte->cacheable, pte->pfn);
264		309
265	/*	310	/*
266	* The entry is to be updated in TLB.	311	* The entry is to be updated in TLB.
267	*/	312	*/
268	if ((badvaddr/PAGE_SIZE) % 2 == 0)	313	if ((badvaddr/PAGE_SIZE) % 2 == 0)
269	cp0_entry_lo0_write(lo.value);	314	cp0_entry_lo0_write(lo.value);
270	else	315	else
271	cp0_entry_lo1_write(lo.value);	316	cp0_entry_lo1_write(lo.value);
272	cp0_pagemask_write(TLB_PAGE_MASK_16K);	317	cp0_pagemask_write(TLB_PAGE_MASK_16K);
273	tlbwi();	318	tlbwi();
274		319
275	page_table_unlock(AS, true);	320	page_table_unlock(AS, true);
276	return;	321	return;
277		322
278	fail:	323	fail:
279	page_table_unlock(AS, true);	324	page_table_unlock(AS, true);
280	tlb_modified_fail(istate);	325	tlb_modified_fail(istate);
281	}	326	}
282		327
283	void tlb_refill_fail(istate_t *istate)	328	void tlb_refill_fail(istate_t *istate)
284	{	329	{
285	char *symbol = "";	330	char *symbol = "";
286	char *sym2 = "";	331	char *sym2 = "";
287		332
288	char *s = get_symtab_entry(istate->epc);	333	char *s = get_symtab_entry(istate->epc);
289	if (s)	334	if (s)
290	symbol = s;	335	symbol = s;
291	s = get_symtab_entry(istate->ra);	336	s = get_symtab_entry(istate->ra);
292	if (s)	337	if (s)
293	sym2 = s;	338	sym2 = s;
294	panic("%X: TLB Refill Exception at %X(%s<-%s)\n", cp0_badvaddr_read(), istate->epc, symbol, sym2);	339	panic("%X: TLB Refill Exception at %X(%s<-%s)\n", cp0_badvaddr_read(), istate->epc, symbol, sym2);
295	}	340	}
296		341
297		342
298	void tlb_invalid_fail(istate_t *istate)	343	void tlb_invalid_fail(istate_t *istate)
299	{	344	{
300	char *symbol = "";	345	char *symbol = "";
301		346
302	char *s = get_symtab_entry(istate->epc);	347	char *s = get_symtab_entry(istate->epc);
303	if (s)	348	if (s)
304	symbol = s;	349	symbol = s;
305	panic("%X: TLB Invalid Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);	350	panic("%X: TLB Invalid Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);
306	}	351	}
307		352
308	void tlb_modified_fail(istate_t *istate)	353	void tlb_modified_fail(istate_t *istate)
309	{	354	{
310	char *symbol = "";	355	char *symbol = "";
311		356
312	char *s = get_symtab_entry(istate->epc);	357	char *s = get_symtab_entry(istate->epc);
313	if (s)	358	if (s)
314	symbol = s;	359	symbol = s;
315	panic("%X: TLB Modified Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);	360	panic("%X: TLB Modified Exception at %X(%s)\n", cp0_badvaddr_read(), istate->epc, symbol);
316	}	361	}
317		362
318	/** Try to find PTE for faulting address	363	/** Try to find PTE for faulting address
319	*	364	*
320	* Try to find PTE for faulting address.	365	* Try to find PTE for faulting address.
321	* The AS->lock must be held on entry to this function.	366	* The AS->lock must be held on entry to this function.
322	*	367	*
323	* @param badvaddr Faulting virtual address.	368	* @param badvaddr Faulting virtual address.
-		369	* @param istate Pointer to interrupted state.
-		370	* @param pfrc Pointer to variable where as_page_fault() return code will be stored.
324	*	371	*
325	* @return PTE on success, NULL otherwise.	372	* @return PTE on success, NULL otherwise.
326	*/	373	*/
327	pte_t *find_mapping_and_check(__address badvaddr)	374	pte_t find_mapping_and_check(__address badvaddr, istate_t istate, int *pfrc)
328	{	375	{
329	entry_hi_t hi;	376	entry_hi_t hi;
330	pte_t *pte;	377	pte_t *pte;
331		378
332	hi.value = cp0_entry_hi_read();	379	hi.value = cp0_entry_hi_read();
333		380
334	/*	381	/*
335	* Handler cannot succeed if the ASIDs don't match.	382	* Handler cannot succeed if the ASIDs don't match.
336	*/	383	*/
337	if (hi.asid != AS->asid) {	384	if (hi.asid != AS->asid) {
338	printf("EntryHi.asid=%d, AS->asid=%d\n", hi.asid, AS->asid);	385	printf("EntryHi.asid=%d, AS->asid=%d\n", hi.asid, AS->asid);
339	return NULL;	386	return NULL;
340	}	387	}
341		388
342	/*	389	/*
343	* Check if the mapping exists in page tables.	390	* Check if the mapping exists in page tables.
344	*/	391	*/
345	pte = page_mapping_find(AS, badvaddr);	392	pte = page_mapping_find(AS, badvaddr);
346	if (pte && pte->p) {	393	if (pte && pte->p) {
347	/*	394	/*
348	* Mapping found in page tables.	395	* Mapping found in page tables.
349	* Immediately succeed.	396	* Immediately succeed.
350	*/	397	*/
351	return pte;	398	return pte;
352	} else {	399	} else {
-		400	int rc;
-		401
353	/*	402	/*
354	* Mapping not found in page tables.	403	* Mapping not found in page tables.
355	* Resort to higher-level page fault handler.	404	* Resort to higher-level page fault handler.
356	*/	405	*/
357	page_table_unlock(AS, true);	406	page_table_unlock(AS, true);
358	if (as_page_fault(badvaddr)) {	407	switch (rc = as_page_fault(badvaddr, istate)) {
-		408	case AS_PF_OK:
359	/*	409	/*
360	* The higher-level page fault handler succeeded,	410	* The higher-level page fault handler succeeded,
361	* The mapping ought to be in place.	411	* The mapping ought to be in place.
362	*/	412	*/
363	page_table_lock(AS, true);	413	page_table_lock(AS, true);
364	pte = page_mapping_find(AS, badvaddr);	414	pte = page_mapping_find(AS, badvaddr);
365	ASSERT(pte && pte->p);	415	ASSERT(pte && pte->p);
366	return pte;	416	return pte;
-		417	break;
-		418	case AS_PF_DEFER:
-		419	page_table_lock(AS, true);
-		420	*pfrc = AS_PF_DEFER;
-		421	return NULL;
367	} else {	422	break;
-		423	case AS_PF_FAULT:
368	page_table_lock(AS, true);	424	page_table_lock(AS, true);
369	printf("Page fault.\n");	425	printf("Page fault.\n");
-		426	*pfrc = AS_PF_FAULT;
370	return NULL;	427	return NULL;
-		428	break;
-		429	default:
-		430	panic("unexpected rc (%d)\n", rc);
371	}	431	}
372		432
373	}	433	}
374	}	434	}
375		435
376	void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn)	436	void prepare_entry_lo(entry_lo_t *lo, bool g, bool v, bool d, bool cacheable, __address pfn)
377	{	437	{
378	lo->value = 0;	438	lo->value = 0;
379	lo->g = g;	439	lo->g = g;
380	lo->v = v;	440	lo->v = v;
381	lo->d = d;	441	lo->d = d;
382	lo->c = cacheable ? PAGE_CACHEABLE_EXC_WRITE : PAGE_UNCACHED;	442	lo->c = cacheable ? PAGE_CACHEABLE_EXC_WRITE : PAGE_UNCACHED;
383	lo->pfn = pfn;	443	lo->pfn = pfn;
384	}	444	}
385		445
386	void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr)	446	void prepare_entry_hi(entry_hi_t *hi, asid_t asid, __address addr)
387	{	447	{
388	hi->value = ALIGN_DOWN(addr, PAGE_SIZE * 2);	448	hi->value = ALIGN_DOWN(addr, PAGE_SIZE * 2);
389	hi->asid = asid;	449	hi->asid = asid;
390	}	450	}
391		451
392	/** Print contents of TLB. */	452	/** Print contents of TLB. */
393	void tlb_print(void)	453	void tlb_print(void)
394	{	454	{
395	page_mask_t mask;	455	page_mask_t mask;
396	entry_lo_t lo0, lo1;	456	entry_lo_t lo0, lo1;
397	entry_hi_t hi, hi_save;	457	entry_hi_t hi, hi_save;
398	int i;	458	int i;
399		459
400	hi_save.value = cp0_entry_hi_read();	460	hi_save.value = cp0_entry_hi_read();
401		461
402	printf("TLB:\n");	462	printf("TLB:\n");
403	for (i = 0; i < TLB_ENTRY_COUNT; i++) {	463	for (i = 0; i < TLB_ENTRY_COUNT; i++) {
404	cp0_index_write(i);	464	cp0_index_write(i);
405	tlbr();	465	tlbr();
406		466
407	mask.value = cp0_pagemask_read();	467	mask.value = cp0_pagemask_read();
408	hi.value = cp0_entry_hi_read();	468	hi.value = cp0_entry_hi_read();
409	lo0.value = cp0_entry_lo0_read();	469	lo0.value = cp0_entry_lo0_read();
410	lo1.value = cp0_entry_lo1_read();	470	lo1.value = cp0_entry_lo1_read();
411		471
412	printf("%d: asid=%d, vpn2=%d, mask=%d\tg[0]=%d, v[0]=%d, d[0]=%d, c[0]=%hhd, pfn[0]=%d\n"	472	printf("%d: asid=%d, vpn2=%d, mask=%d\tg[0]=%d, v[0]=%d, d[0]=%d, c[0]=%hhd, pfn[0]=%d\n"
413	"\t\t\t\tg[1]=%d, v[1]=%d, d[1]=%d, c[1]=%hhd, pfn[1]=%d\n",	473	"\t\t\t\tg[1]=%d, v[1]=%d, d[1]=%d, c[1]=%hhd, pfn[1]=%d\n",
414	i, hi.asid, hi.vpn2, mask.mask, lo0.g, lo0.v, lo0.d, lo0.c, lo0.pfn,	474	i, hi.asid, hi.vpn2, mask.mask, lo0.g, lo0.v, lo0.d, lo0.c, lo0.pfn,
415	lo1.g, lo1.v, lo1.d, lo1.c, lo1.pfn);	475	lo1.g, lo1.v, lo1.d, lo1.c, lo1.pfn);
416	}	476	}
417		477
418	cp0_entry_hi_write(hi_save.value);	478	cp0_entry_hi_write(hi_save.value);
419	}	479	}
420		480
421	/** Invalidate all not wired TLB entries. */	481	/** Invalidate all not wired TLB entries. */
422	void tlb_invalidate_all(void)	482	void tlb_invalidate_all(void)
423	{	483	{
424	ipl_t ipl;	484	ipl_t ipl;
425	entry_lo_t lo0, lo1;	485	entry_lo_t lo0, lo1;
426	entry_hi_t hi_save;	486	entry_hi_t hi_save;
427	int i;	487	int i;
428		488
429	hi_save.value = cp0_entry_hi_read();	489	hi_save.value = cp0_entry_hi_read();
430	ipl = interrupts_disable();	490	ipl = interrupts_disable();
431		491
432	for (i = TLB_WIRED; i < TLB_ENTRY_COUNT; i++) {	492	for (i = TLB_WIRED; i < TLB_ENTRY_COUNT; i++) {
433	cp0_index_write(i);	493	cp0_index_write(i);
434	tlbr();	494	tlbr();
435		495
436	lo0.value = cp0_entry_lo0_read();	496	lo0.value = cp0_entry_lo0_read();
437	lo1.value = cp0_entry_lo1_read();	497	lo1.value = cp0_entry_lo1_read();
438		498
439	lo0.v = 0;	499	lo0.v = 0;
440	lo1.v = 0;	500	lo1.v = 0;

Subversion Repositories HelenOS

(root)/kernel/trunk/arch/mips32/src/mm/tlb.c – Rev 1196 → 1288