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r: 155836
b: refs/heads/master
c: 3863dbc
h: refs/heads/master
v: v3
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Michal Simek committed Jul 27, 2009
1 parent 5645322 commit e5014b4
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Showing 3 changed files with 48 additions and 65 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 94ad8eb854cbc1cf875a318f9b97314ddc6b1560
refs/heads/master: 3863dbceac7e69642b95f43de1c12c6236fdbe5b
109 changes: 46 additions & 63 deletions trunk/arch/microblaze/kernel/hw_exception_handler.S
Original file line number Diff line number Diff line change
Expand Up @@ -74,6 +74,7 @@

#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/signal.h>
#include <asm/asm-offsets.h>

/* Helpful Macros */
Expand Down Expand Up @@ -428,19 +429,9 @@ handle_unaligned_ex:
mfs r17, rbtr; /* ESR[DS] set - return address in BTR */
nop
_no_delayslot:
#endif

#ifdef CONFIG_MMU
/* Check if unaligned address is last on a 4k page */
andi r5, r4, 0xffc
xori r5, r5, 0xffc
bnei r5, _unaligned_ex2
_unaligned_ex1:
RESTORE_STATE;
/* Another page must be accessed or physical address not in page table */
bri unaligned_data_trap

_unaligned_ex2:
/* jump to high level unaligned handler */
RESTORE_STATE;
bri unaligned_data_trap
#endif
andi r6, r3, 0x3E0; /* Mask and extract the register operand */
srl r6, r6; /* r6 >> 5 */
Expand All @@ -450,45 +441,6 @@ _no_delayslot:
srl r6, r6;
/* Store the register operand in a temporary location */
sbi r6, r0, TOPHYS(ex_reg_op);
#ifdef CONFIG_MMU
/* Get physical address */
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
*/
ori r5, r0, CONFIG_KERNEL_START
cmpu r5, r4, r5
bgti r5, _unaligned_ex3
ori r5, r0, swapper_pg_dir
bri _unaligned_ex4

/* Get the PGD for the current thread. */
_unaligned_ex3: /* user thread */
addi r5 ,CURRENT_TASK, TOPHYS(0); /* get current task address */
lwi r5, r5, TASK_THREAD + PGDIR
_unaligned_ex4:
tophys(r5,r5)
BSRLI(r6,r4,20) /* Create L1 (pgdir/pmd) address */
andi r6, r6, 0xffc
/* Assume pgdir aligned on 4K boundary, no need for "andi r5,r5,0xfffff003" */
or r5, r5, r6
lwi r6, r5, 0 /* Get L1 entry */
andi r5, r6, 0xfffff000 /* Extract L2 (pte) base address. */
beqi r5, _unaligned_ex1 /* Bail if no table */

tophys(r5,r5)
BSRLI(r6,r4,10) /* Compute PTE address */
andi r6, r6, 0xffc
andi r5, r5, 0xfffff003
or r5, r5, r6
lwi r5, r5, 0 /* Get Linux PTE */

andi r6, r5, _PAGE_PRESENT
beqi r6, _unaligned_ex1 /* Bail if no page */

andi r5, r5, 0xfffff000 /* Extract RPN */
andi r4, r4, 0x00000fff /* Extract offset */
or r4, r4, r5 /* Create physical address */
#endif /* CONFIG_MMU */

andi r6, r3, 0x400; /* Extract ESR[S] */
bnei r6, ex_sw;
Expand Down Expand Up @@ -959,15 +911,15 @@ _unaligned_data_exception:
andi r6, r3, 0x800; /* Extract ESR[W] - delay slot */
ex_lw_vm:
beqid r6, ex_lhw_vm;
lbui r5, r4, 0; /* Exception address in r4 - delay slot */
load1: lbui r5, r4, 0; /* Exception address in r4 - delay slot */
/* Load a word, byte-by-byte from destination address and save it in tmp space*/
la r6, r0, ex_tmp_data_loc_0;
sbi r5, r6, 0;
lbui r5, r4, 1;
load2: lbui r5, r4, 1;
sbi r5, r6, 1;
lbui r5, r4, 2;
load3: lbui r5, r4, 2;
sbi r5, r6, 2;
lbui r5, r4, 3;
load4: lbui r5, r4, 3;
sbi r5, r6, 3;
brid ex_lw_tail_vm;
/* Get the destination register value into r3 - delay slot */
Expand All @@ -977,7 +929,7 @@ ex_lhw_vm:
* save it in tmp space */
la r6, r0, ex_tmp_data_loc_0;
sbi r5, r6, 0;
lbui r5, r4, 1;
load5: lbui r5, r4, 1;
sbi r5, r6, 1;
lhui r3, r6, 0; /* Get the destination register value into r3 */
ex_lw_tail_vm:
Expand All @@ -996,22 +948,53 @@ ex_sw_tail_vm:
swi r3, r5, 0; /* Get the word - delay slot */
/* Store the word, byte-by-byte into destination address */
lbui r3, r5, 0;
sbi r3, r4, 0;
store1: sbi r3, r4, 0;
lbui r3, r5, 1;
sbi r3, r4, 1;
store2: sbi r3, r4, 1;
lbui r3, r5, 2;
sbi r3, r4, 2;
store3: sbi r3, r4, 2;
lbui r3, r5, 3;
brid ret_from_exc;
sbi r3, r4, 3; /* Delay slot */
store4: sbi r3, r4, 3; /* Delay slot */
ex_shw_vm:
/* Store the lower half-word, byte-by-byte into destination address */
lbui r3, r5, 2;
sbi r3, r4, 0;
store5: sbi r3, r4, 0;
lbui r3, r5, 3;
brid ret_from_exc;
sbi r3, r4, 1; /* Delay slot */
store6: sbi r3, r4, 1; /* Delay slot */
ex_sw_end_vm: /* Exception handling of store word, ends. */

/* We have to prevent cases that get/put_user macros get unaligned pointer
* to bad page area. We have to find out which origin instruction caused it
* and called fixup for that origin instruction not instruction in unaligned
* handler */
ex_unaligned_fixup:
ori r5, r7, 0 /* setup pointer to pt_regs */
lwi r6, r7, PT_PC; /* faulting address is one instruction above */
addik r6, r6, -4 /* for finding proper fixup */
swi r6, r7, PT_PC; /* a save back it to PT_PC */
addik r7, r0, SIGSEGV
/* call bad_page_fault for finding aligned fixup, fixup address is saved
* in PT_PC which is used as return address from exception */
la r15, r0, ret_from_exc-8 /* setup return address */
brid bad_page_fault
nop

/* We prevent all load/store because it could failed any attempt to access */
.section __ex_table,"a";
.word load1,ex_unaligned_fixup;
.word load2,ex_unaligned_fixup;
.word load3,ex_unaligned_fixup;
.word load4,ex_unaligned_fixup;
.word load5,ex_unaligned_fixup;
.word store1,ex_unaligned_fixup;
.word store2,ex_unaligned_fixup;
.word store3,ex_unaligned_fixup;
.word store4,ex_unaligned_fixup;
.word store5,ex_unaligned_fixup;
.word store6,ex_unaligned_fixup;
.previous;
.end _unaligned_data_exception
#endif /* CONFIG_MMU */

Expand Down
2 changes: 1 addition & 1 deletion trunk/arch/microblaze/mm/fault.c
Original file line number Diff line number Diff line change
Expand Up @@ -69,7 +69,7 @@ static int store_updates_sp(struct pt_regs *regs)
* It is called from do_page_fault above and from some of the procedures
* in traps.c.
*/
static void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
{
const struct exception_table_entry *fixup;
/* MS: no context */
Expand Down

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