* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
+ * vineetg: May 2011
+ * -Userspace unaligned access emulation
+ *
+ * vineetg: Feb 2011 (ptrace low level code fixes)
+ * -traced syscall return code (r0) was not saved into pt_regs for restoring
+ * into user reg-file when traded task rets to user space.
+ * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs)
+ * were not invoking post-syscall trace hook (jumping directly into
+ * ret_from_system_call)
+ *
* vineetg: Nov 2010:
* -Vector table jumps (@8 bytes) converted into branches (@4 bytes)
* -To maintain the slot size of 8 bytes/vector, added nop, which is
* exception. Thus FAKE RTIE needed in low level Priv-Violation handler.
* Instr Error could also cause similar scenario, so same there as well.
*
+ * Vineetg: March 2009 (Supporting 2 levels of Interrupts)
+ *
* Vineetg: Aug 28th 2008: Bug #94984
* -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap
* Normally CPU does this automatically, however when doing FAKE rtie,
* was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit,
* setting it and not clearing it clears ZOL context
*
+ * Vineetg: May 16th, 2008
+ * - r25 now contains the Current Task when in kernel
+ *
* Vineetg: Dec 22, 2007
* Minor Surgery of Low Level ISR to make it SMP safe
* - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR
VECTOR instr_service ; 0x10, Instrn Error (0x2)
; ******************** Device ISRs **********************
+#ifdef CONFIG_ARC_IRQ3_LV2
+VECTOR handle_interrupt_level2
+#else
VECTOR handle_interrupt_level1
+#endif
VECTOR handle_interrupt_level1
+#ifdef CONFIG_ARC_IRQ5_LV2
+VECTOR handle_interrupt_level2
+#else
VECTOR handle_interrupt_level1
+#endif
+#ifdef CONFIG_ARC_IRQ6_LV2
+VECTOR handle_interrupt_level2
+#else
VECTOR handle_interrupt_level1
+#endif
.rept 25
VECTOR handle_interrupt_level1 ; Other devices
;##################### Scratch Mem for IRQ stack switching #############
- .section .data ; NOT .global
+ARCFP_DATA int1_saved_reg
.align 32
.type int1_saved_reg, @object
.size int1_saved_reg, 4
int1_saved_reg:
.zero 4
+/* Each Interrupt level needs it's own scratch */
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+
+ARCFP_DATA int2_saved_reg
+ .type int2_saved_reg, @object
+ .size int2_saved_reg, 4
+int2_saved_reg:
+ .zero 4
+
+#endif
+
; ---------------------------------------------
.section .text, "ax",@progbits
;##################### Interrupt Handling ##############################
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+; ---------------------------------------------
+; Level 2 ISR: Can interrupt a Level 1 ISR
+; ---------------------------------------------
+ARC_ENTRY handle_interrupt_level2
+
+ ; TODO-vineetg for SMP this wont work
+ ; free up r9 as scratchpad
+ st r9, [@int2_saved_reg]
+
+ ;Which mode (user/kernel) was the system in when intr occured
+ lr r9, [status32_l2]
+
+ SWITCH_TO_KERNEL_STK
+ SAVE_ALL_INT2
+
+ ;------------------------------------------------------
+ ; if L2 IRQ interrupted a L1 ISR, disable preemption
+ ;------------------------------------------------------
+
+ ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs)
+ bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal
+
+ ; A1 is set in status32_l2
+ ; bump thread_info->preempt_count (Disable preemption)
+ GET_CURR_THR_INFO_FROM_SP r10
+ ld r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+ add r9, r9, 1
+ st r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+1:
+ ;------------------------------------------------------
+ ; setup params for Linux common ISR and invoke it
+ ;------------------------------------------------------
+ lr r0, [icause2]
+ and r0, r0, 0x1f
+
+ bl.d @arch_do_IRQ
+ mov r1, sp
+
+ mov r8,0x2
+ sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg
+
+ b ret_from_exception
+
+ARC_EXIT handle_interrupt_level2
+
+#endif
+
; ---------------------------------------------
; Level 1 ISR
; ---------------------------------------------
ARC_ENTRY handle_interrupt_level1
/* free up r9 as scratchpad */
+#ifdef CONFIG_SMP
+ sr r9, [ARC_REG_SCRATCH_DATA0]
+#else
st r9, [@int1_saved_reg]
+#endif
;Which mode (user/kernel) was the system in when intr occured
lr r9, [status32_l1]
mov r1, r4 ; faulting address
mov r2, sp ; pt_regs
+#ifdef CONFIG_ARC_MISALIGN_ACCESS
+ SAVE_CALLEE_SAVED_USER
+ mov r3, sp ; callee_regs
+#endif
+
bl do_misaligned_access
+
+#ifdef CONFIG_ARC_MISALIGN_ACCESS
+ DISCARD_CALLEE_SAVED_USER
+#endif
+
b ret_from_exception
ARC_EXIT EV_TLBProtV
b ret_from_exception
ARC_EXIT EV_Extension
+;######################### System Call Tracing #########################
+
+tracesys:
+ ; save EFA in case tracer wants the PC of traced task
+ ; using ERET won't work since next-PC has already committed
+ lr r12, [efa]
+ GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11
+ st r12, [r11, THREAD_FAULT_ADDR] ; thread.fault_address
+
+ ; PRE Sys Call Ptrace hook
+ mov r0, sp ; pt_regs needed
+ bl @syscall_trace_entry
+
+ ; Tracing code now returns the syscall num (orig or modif)
+ mov r8, r0
+
+ ; Do the Sys Call as we normally would.
+ ; Validate the Sys Call number
+ cmp r8, NR_syscalls
+ mov.hi r0, -ENOSYS
+ bhi tracesys_exit
+
+ ; Restore the sys-call args. Mere invocation of the hook abv could have
+ ; clobbered them (since they are in scratch regs). The tracer could also
+ ; have deliberately changed the syscall args: r0-r7
+ ld r0, [sp, PT_r0]
+ ld r1, [sp, PT_r1]
+ ld r2, [sp, PT_r2]
+ ld r3, [sp, PT_r3]
+ ld r4, [sp, PT_r4]
+ ld r5, [sp, PT_r5]
+ ld r6, [sp, PT_r6]
+ ld r7, [sp, PT_r7]
+ ld.as r9, [sys_call_table, r8]
+ jl [r9] ; Entry into Sys Call Handler
+
+tracesys_exit:
+ st r0, [sp, PT_r0] ; sys call return value in pt_regs
+
+ ;POST Sys Call Ptrace Hook
+ bl @syscall_trace_exit
+ b ret_from_exception ; NOT ret_from_system_call at is saves r0 which
+ ; we'd done before calling post hook above
+
;################### Break Point TRAP ##########################
; ======= (5b) Trap is due to Break-Point =========
trap_with_param:
- ;make sure orig_r8 is a positive value
- st NR_syscalls + 2, [sp, PT_orig_r8]
+ ; stop_pc info by gdb needs this info
+ stw orig_r8_IS_BRKPT, [sp, PT_orig_r8]
mov r0, r12
lr r1, [efa]
; Before doing anything, return from CPU Exception Mode
FAKE_RET_FROM_EXCPN r11
+ ; If syscall tracing ongoing, invoke pre-pos-hooks
+ GET_CURR_THR_INFO_FLAGS r10
+ btst r10, TIF_SYSCALL_TRACE
+ bnz tracesys ; this never comes back
+
;============ This is normal System Call case ==========
; Sys-call num shd not exceed the total system calls avail
cmp r8, NR_syscalls
; XXX can this be optimised out
IRQ_DISABLE_SAVE r9, r10 ;@r10 has prisitine (pre-disable) copy
+#ifdef CONFIG_ARC_CURR_IN_REG
+ ; Restore User R25
+ ; Earlier this used to be only for returning to user mode
+ ; However with 2 levels of IRQ this can also happen even if
+ ; in kernel mode
+ ld r9, [sp, PT_sp]
+ brhs r9, VMALLOC_START, 8f
+ RESTORE_USER_R25
+8:
+#endif
+
; Restore REG File. In case multiple Events outstanding,
; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None
; Note that we use realtime STATUS32 (not pt_regs->status32) to
not_exception:
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+
+ bbit0 r10, STATUS_A2_BIT, not_level2_interrupt
+
+ ;------------------------------------------------------------------
+ ; if L2 IRQ interrupted a L1 ISR, we'd disbaled preemption earlier
+ ; so that sched doesnt move to new task, causing L1 to be delayed
+ ; undeterministically. Now that we've achieved that, lets reset
+ ; things to what they were, before returning from L2 context
+ ;----------------------------------------------------------------
+
+ ldw r9, [sp, PT_orig_r8] ; get orig_r8 to make sure it is
+ brne r9, orig_r8_IS_IRQ2, 149f ; infact a L2 ISR ret path
+
+ ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs)
+ bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal
+
+ ; A1 is set in status32_l2
+ ; decrement thread_info->preempt_count (re-enable preemption)
+ GET_CURR_THR_INFO_FROM_SP r10
+ ld r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+ ; paranoid check, given A1 was active when A2 happened, preempt count
+ ; must not be 0 beccause we would have incremented it.
+ ; If this does happen we simply HALT as it means a BUG !!!
+ cmp r9, 0
+ bnz 2f
+ flag 1
+
+2:
+ sub r9, r9, 1
+ st r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+149:
+ ;return from level 2
+ RESTORE_ALL_INT2
+debug_marker_l2:
+ rtie
+
+not_level2_interrupt:
+
+#endif
+
bbit0 r10, STATUS_A1_BIT, not_level1_interrupt
;return from level 1
;################### Special Sys Call Wrappers ##########################
-; TBD: call do_fork directly from here
-ARC_ENTRY sys_fork_wrapper
- SAVE_CALLEE_SAVED_USER
- bl @sys_fork
- DISCARD_CALLEE_SAVED_USER
-
- b ret_from_system_call
-ARC_EXIT sys_fork_wrapper
-
-ARC_ENTRY sys_vfork_wrapper
- SAVE_CALLEE_SAVED_USER
- bl @sys_vfork
- DISCARD_CALLEE_SAVED_USER
-
- b ret_from_system_call
-ARC_EXIT sys_vfork_wrapper
-
ARC_ENTRY sys_clone_wrapper
SAVE_CALLEE_SAVED_USER
bl @sys_clone
DISCARD_CALLEE_SAVED_USER
+ GET_CURR_THR_INFO_FLAGS r10
+ btst r10, TIF_SYSCALL_TRACE
+ bnz tracesys_exit
+
b ret_from_system_call
ARC_EXIT sys_clone_wrapper
+
+#ifdef CONFIG_ARC_DW2_UNWIND
+; Workaround for bug 94179 (STAR ):
+; Despite -fasynchronous-unwind-tables, linker is not making dwarf2 unwinder
+; section (.debug_frame) as loadable. So we force it here.
+; This also fixes STAR 9000487933 where the prev-workaround (objcopy --setflag)
+; would not work after a clean build due to kernel build system dependencies.
+.section .debug_frame, "wa",@progbits
+#endif
projects / karo-tx-linux.git / blobdiff