.align 2
bral do_dtlb_modified
- /*
- * r0 : PGD/PT/PTE
- * r1 : Offending address
- * r2 : Scratch register
- * r3 : Cause (5, 12 or 13)
- */
#define tlbmiss_save pushm r0-r3
#define tlbmiss_restore popm r0-r3
- .section .tlbx.ex.text,"ax",@progbits
+ .org 0x50
.global itlb_miss
itlb_miss:
tlbmiss_save
rjmp tlb_miss_common
- .section .tlbr.ex.text,"ax",@progbits
+ .org 0x60
dtlb_miss_read:
tlbmiss_save
rjmp tlb_miss_common
- .section .tlbw.ex.text,"ax",@progbits
+ .org 0x70
dtlb_miss_write:
tlbmiss_save
.global tlb_miss_common
+ .align 2
tlb_miss_common:
mfsr r0, SYSREG_TLBEAR
mfsr r1, SYSREG_PTBR
- /* Is it the vmalloc space? */
- bld r0, 31
- brcs handle_vmalloc_miss
-
- /* First level lookup */
+ /*
+ * First level lookup: The PGD contains virtual pointers to
+ * the second-level page tables, but they may be NULL if not
+ * present.
+ */
pgtbl_lookup:
lsr r2, r0, PGDIR_SHIFT
ld.w r3, r1[r2 << 2]
bfextu r1, r0, PAGE_SHIFT, PGDIR_SHIFT - PAGE_SHIFT
- bld r3, _PAGE_BIT_PRESENT
- brcc page_table_not_present
-
- /* Translate to virtual address in P1. */
- andl r3, 0xf000
- sbr r3, 31
+ cp.w r3, 0
+ breq page_table_not_present
/* Second level lookup */
ld.w r2, r3[r1 << 2]
tlbmiss_restore
rete
-handle_vmalloc_miss:
- /* Simply do the lookup in init's page table */
+ /* The slow path of the TLB miss handler */
+ .align 2
+page_table_not_present:
+ /* Do we need to synchronize with swapper_pg_dir? */
+ bld r0, 31
+ brcs sync_with_swapper_pg_dir
+
+page_not_present:
+ tlbmiss_restore
+ sub sp, 4
+ stmts --sp, r0-lr
+ rcall save_full_context_ex
+ mfsr r12, SYSREG_ECR
+ mov r11, sp
+ rcall do_page_fault
+ rjmp ret_from_exception
+
+ .align 2
+sync_with_swapper_pg_dir:
+ /*
+ * If swapper_pg_dir contains a non-NULL second-level page
+ * table pointer, copy it into the current PGD. If not, we
+ * must handle it as a full-blown page fault.
+ *
+ * Jumping back to pgtbl_lookup causes an unnecessary lookup,
+ * but it is guaranteed to be a cache hit, it won't happen
+ * very often, and we absolutely do not want to sacrifice any
+ * performance in the fast path in order to improve this.
+ */
mov r1, lo(swapper_pg_dir)
orh r1, hi(swapper_pg_dir)
+ ld.w r3, r1[r2 << 2]
+ cp.w r3, 0
+ breq page_not_present
+ mfsr r1, SYSREG_PTBR
+ st.w r1[r2 << 2], r3
rjmp pgtbl_lookup
+ /*
+ * We currently have two bytes left at this point until we
+ * crash into the system call handler...
+ *
+ * Don't worry, the assembler will let us know.
+ */
+
/* --- System Call --- */
- .section .scall.text,"ax",@progbits
+ .org 0x100
system_call:
#ifdef CONFIG_PREEMPT
mask_interrupts
brcc syscall_exit_cont
rjmp enter_monitor_mode
- /* The slow path of the TLB miss handler */
-page_table_not_present:
-page_not_present:
- tlbmiss_restore
- sub sp, 4
- stmts --sp, r0-lr
- rcall save_full_context_ex
- mfsr r12, SYSREG_ECR
- mov r11, sp
- rcall do_page_fault
- rjmp ret_from_exception
-
/* This function expects to find offending PC in SYSREG_RAR_EX */
.type save_full_context_ex, @function
.align 2
.section .irq.text,"ax",@progbits
-.global cpu_idle_sleep
-cpu_idle_sleep:
- mask_interrupts
- get_thread_info r8
- ld.w r9, r8[TI_flags]
- bld r9, TIF_NEED_RESCHED
- brcs cpu_idle_enable_int_and_exit
- sbr r9, TIF_CPU_GOING_TO_SLEEP
- st.w r8[TI_flags], r9
- unmask_interrupts
- sleep 0
-cpu_idle_skip_sleep:
- mask_interrupts
- ld.w r9, r8[TI_flags]
- cbr r9, TIF_CPU_GOING_TO_SLEEP
- st.w r8[TI_flags], r9
-cpu_idle_enable_int_and_exit:
- unmask_interrupts
- retal r12
-
.global irq_level0
.global irq_level1
.global irq_level2
git.openpandora.org / pandora-kernel.git / blobdiff