; ; Port on Texas Instruments TMS320C6x architecture ; ; Copyright (C) 2004-2011 Texas Instruments Incorporated ; Author: Aurelien Jacquiot (aurelien.jacquiot@virtuallogix.com) ; Updated for 2.6.34: Mark Salter <msalter@redhat.com> ; ; This program is free software; you can redistribute it and/or modify ; it under the terms of the GNU General Public License version 2 as ; published by the Free Software Foundation. ; #include <linux/sys.h> #include <linux/linkage.h> #include <asm/thread_info.h> #include <asm/asm-offsets.h> #include <asm/unistd.h> #include <asm/errno.h> ; Registers naming #define DP B14 #define SP B15 #ifndef CONFIG_PREEMPT #define resume_kernel restore_all #endif .altmacro .macro MASK_INT reg MVC .S2 CSR,reg CLR .S2 reg,0,0,reg MVC .S2 reg,CSR .endm .macro UNMASK_INT reg MVC .S2 CSR,reg SET .S2 reg,0,0,reg MVC .S2 reg,CSR .endm .macro GET_THREAD_INFO reg SHR .S1X SP,THREAD_SHIFT,reg SHL .S1 reg,THREAD_SHIFT,reg .endm ;; ;; This defines the normal kernel pt_regs layout. ;; .macro SAVE_ALL __rp __tsr STW .D2T2 B0,*SP--[2] ; save original B0 MVKL .S2 current_ksp,B0 MVKH .S2 current_ksp,B0 LDW .D2T2 *B0,B1 ; KSP NOP 3 STW .D2T2 B1,*+SP[1] ; save original B1 XOR .D2 SP,B1,B0 ; (SP ^ KSP) LDW .D2T2 *+SP[1],B1 ; restore B0/B1 LDW .D2T2 *++SP[2],B0 SHR .S2 B0,THREAD_SHIFT,B0 ; 0 if already using kstack [B0] STDW .D2T2 SP:DP,*--B1[1] ; user: save user sp/dp kstack [B0] MV .S2 B1,SP ; and switch to kstack ||[!B0] STDW .D2T2 SP:DP,*--SP[1] ; kernel: save on current stack SUBAW .D2 SP,2,SP ADD .D1X SP,-8,A15 || STDW .D2T1 A15:A14,*SP--[16] ; save A15:A14 STDW .D2T2 B13:B12,*SP--[1] || STDW .D1T1 A13:A12,*A15--[1] || MVC .S2 __rp,B13 STDW .D2T2 B11:B10,*SP--[1] || STDW .D1T1 A11:A10,*A15--[1] || MVC .S2 CSR,B12 STDW .D2T2 B9:B8,*SP--[1] || STDW .D1T1 A9:A8,*A15--[1] || MVC .S2 RILC,B11 STDW .D2T2 B7:B6,*SP--[1] || STDW .D1T1 A7:A6,*A15--[1] || MVC .S2 ILC,B10 STDW .D2T2 B5:B4,*SP--[1] || STDW .D1T1 A5:A4,*A15--[1] STDW .D2T2 B3:B2,*SP--[1] || STDW .D1T1 A3:A2,*A15--[1] || MVC .S2 __tsr,B5 STDW .D2T2 B1:B0,*SP--[1] || STDW .D1T1 A1:A0,*A15--[1] || MV .S1X B5,A5 STDW .D2T2 B31:B30,*SP--[1] || STDW .D1T1 A31:A30,*A15--[1] STDW .D2T2 B29:B28,*SP--[1] || STDW .D1T1 A29:A28,*A15--[1] STDW .D2T2 B27:B26,*SP--[1] || STDW .D1T1 A27:A26,*A15--[1] STDW .D2T2 B25:B24,*SP--[1] || STDW .D1T1 A25:A24,*A15--[1] STDW .D2T2 B23:B22,*SP--[1] || STDW .D1T1 A23:A22,*A15--[1] STDW .D2T2 B21:B20,*SP--[1] || STDW .D1T1 A21:A20,*A15--[1] STDW .D2T2 B19:B18,*SP--[1] || STDW .D1T1 A19:A18,*A15--[1] STDW .D2T2 B17:B16,*SP--[1] || STDW .D1T1 A17:A16,*A15--[1] STDW .D2T2 B13:B12,*SP--[1] ; save PC and CSR STDW .D2T2 B11:B10,*SP--[1] ; save RILC and ILC STDW .D2T1 A5:A4,*SP--[1] ; save TSR and orig A4 ;; We left an unused word on the stack just above pt_regs. ;; It is used to save whether or not this frame is due to ;; a syscall. It is cleared here, but the syscall handler ;; sets it to a non-zero value. MVK .L2 0,B1 STW .D2T2 B1,*+SP(REGS__END+8) ; clear syscall flag .endm .macro RESTORE_ALL __rp __tsr LDDW .D2T2 *++SP[1],B9:B8 ; get TSR (B9) LDDW .D2T2 *++SP[1],B11:B10 ; get RILC (B11) and ILC (B10) LDDW .D2T2 *++SP[1],B13:B12 ; get PC (B13) and CSR (B12) ADDAW .D1X SP,30,A15 LDDW .D1T1 *++A15[1],A17:A16 || LDDW .D2T2 *++SP[1],B17:B16 LDDW .D1T1 *++A15[1],A19:A18 || LDDW .D2T2 *++SP[1],B19:B18 LDDW .D1T1 *++A15[1],A21:A20 || LDDW .D2T2 *++SP[1],B21:B20 LDDW .D1T1 *++A15[1],A23:A22 || LDDW .D2T2 *++SP[1],B23:B22 LDDW .D1T1 *++A15[1],A25:A24 || LDDW .D2T2 *++SP[1],B25:B24 LDDW .D1T1 *++A15[1],A27:A26 || LDDW .D2T2 *++SP[1],B27:B26 LDDW .D1T1 *++A15[1],A29:A28 || LDDW .D2T2 *++SP[1],B29:B28 LDDW .D1T1 *++A15[1],A31:A30 || LDDW .D2T2 *++SP[1],B31:B30 LDDW .D1T1 *++A15[1],A1:A0 || LDDW .D2T2 *++SP[1],B1:B0 LDDW .D1T1 *++A15[1],A3:A2 || LDDW .D2T2 *++SP[1],B3:B2 || MVC .S2 B9,__tsr LDDW .D1T1 *++A15[1],A5:A4 || LDDW .D2T2 *++SP[1],B5:B4 || MVC .S2 B11,RILC LDDW .D1T1 *++A15[1],A7:A6 || LDDW .D2T2 *++SP[1],B7:B6 || MVC .S2 B10,ILC LDDW .D1T1 *++A15[1],A9:A8 || LDDW .D2T2 *++SP[1],B9:B8 || MVC .S2 B13,__rp LDDW .D1T1 *++A15[1],A11:A10 || LDDW .D2T2 *++SP[1],B11:B10 || MVC .S2 B12,CSR LDDW .D1T1 *++A15[1],A13:A12 || LDDW .D2T2 *++SP[1],B13:B12 MV .D2X A15,SP || MVKL .S1 current_ksp,A15 MVKH .S1 current_ksp,A15 || ADDAW .D1X SP,6,A14 STW .D1T1 A14,*A15 ; save kernel stack pointer LDDW .D2T1 *++SP[1],A15:A14 B .S2 __rp ; return from interruption LDDW .D2T2 *+SP[1],SP:DP NOP 4 .endm .section .text ;; ;; Jump to schedule() then return to ret_from_exception ;; _reschedule: #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 schedule,A0 MVKH .S1 schedule,A0 B .S2X A0 #else B .S1 schedule #endif ADDKPC .S2 ret_from_exception,B3,4 ;; ;; Called before syscall handler when process is being debugged ;; tracesys_on: #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 syscall_trace_entry,A0 MVKH .S1 syscall_trace_entry,A0 B .S2X A0 #else B .S1 syscall_trace_entry #endif ADDKPC .S2 ret_from_syscall_trace,B3,3 ADD .S1X 8,SP,A4 ret_from_syscall_trace: ;; tracing returns (possibly new) syscall number MV .D2X A4,B0 || MVK .S2 __NR_syscalls,B1 CMPLTU .L2 B0,B1,B1 [!B1] BNOP .S2 ret_from_syscall_function,5 || MVK .S1 -ENOSYS,A4 ;; reload syscall args from (possibly modified) stack frame ;; and get syscall handler addr from sys_call_table: LDW .D2T2 *+SP(REGS_B4+8),B4 || MVKL .S2 sys_call_table,B1 LDW .D2T1 *+SP(REGS_A6+8),A6 || MVKH .S2 sys_call_table,B1 LDW .D2T2 *+B1[B0],B0 || MVKL .S2 ret_from_syscall_function,B3 LDW .D2T2 *+SP(REGS_B6+8),B6 || MVKH .S2 ret_from_syscall_function,B3 LDW .D2T1 *+SP(REGS_A8+8),A8 LDW .D2T2 *+SP(REGS_B8+8),B8 NOP ; B0 = sys_call_table[__NR_*] BNOP .S2 B0,5 ; branch to syscall handler || LDW .D2T1 *+SP(REGS_ORIG_A4+8),A4 syscall_exit_work: AND .D1 _TIF_SYSCALL_TRACE,A2,A0 [!A0] BNOP .S1 work_pending,5 [A0] B .S2 syscall_trace_exit ADDKPC .S2 resume_userspace,B3,1 MVC .S2 CSR,B1 SET .S2 B1,0,0,B1 MVC .S2 B1,CSR ; enable ints work_pending: AND .D1 _TIF_NEED_RESCHED,A2,A0 [!A0] BNOP .S1 work_notifysig,5 work_resched: #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 schedule,A1 MVKH .S1 schedule,A1 B .S2X A1 #else B .S2 schedule #endif ADDKPC .S2 work_rescheduled,B3,4 work_rescheduled: ;; make sure we don't miss an interrupt setting need_resched or ;; sigpending between sampling and the rti MASK_INT B2 GET_THREAD_INFO A12 LDW .D1T1 *+A12(THREAD_INFO_FLAGS),A2 MVK .S1 _TIF_WORK_MASK,A1 MVK .S1 _TIF_NEED_RESCHED,A3 NOP 2 AND .D1 A1,A2,A0 || AND .S1 A3,A2,A1 [!A0] BNOP .S1 restore_all,5 [A1] BNOP .S1 work_resched,5 work_notifysig: ;; enable interrupts for do_notify_resume() UNMASK_INT B2 B .S2 do_notify_resume LDW .D2T1 *+SP(REGS__END+8),A6 ; syscall flag ADDKPC .S2 resume_userspace,B3,1 ADD .S1X 8,SP,A4 ; pt_regs pointer is first arg MV .D2X A2,B4 ; thread_info flags is second arg ;; ;; On C64x+, the return way from exception and interrupt ;; is a little bit different ;; ENTRY(ret_from_exception) #ifdef CONFIG_PREEMPT MASK_INT B2 #endif ENTRY(ret_from_interrupt) ;; ;; Check if we are comming from user mode. ;; LDW .D2T2 *+SP(REGS_TSR+8),B0 MVK .S2 0x40,B1 NOP 3 AND .D2 B0,B1,B0 [!B0] BNOP .S2 resume_kernel,5 resume_userspace: ;; make sure we don't miss an interrupt setting need_resched or ;; sigpending between sampling and the rti MASK_INT B2 GET_THREAD_INFO A12 LDW .D1T1 *+A12(THREAD_INFO_FLAGS),A2 MVK .S1 _TIF_WORK_MASK,A1 MVK .S1 _TIF_NEED_RESCHED,A3 NOP 2 AND .D1 A1,A2,A0 [A0] BNOP .S1 work_pending,5 BNOP .S1 restore_all,5 ;; ;; System call handling ;; B0 = syscall number (in sys_call_table) ;; A4,B4,A6,B6,A8,B8 = arguments of the syscall function ;; A4 is the return value register ;; system_call_saved: MVK .L2 1,B2 STW .D2T2 B2,*+SP(REGS__END+8) ; set syscall flag MVC .S2 B2,ECR ; ack the software exception UNMASK_INT B2 ; re-enable global IT system_call_saved_noack: ;; Check system call number MVK .S2 __NR_syscalls,B1 #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 sys_ni_syscall,A0 #endif CMPLTU .L2 B0,B1,B1 #ifdef CONFIG_C6X_BIG_KERNEL || MVKH .S1 sys_ni_syscall,A0 #endif ;; Check for ptrace GET_THREAD_INFO A12 #ifdef CONFIG_C6X_BIG_KERNEL [!B1] B .S2X A0 #else [!B1] B .S2 sys_ni_syscall #endif [!B1] ADDKPC .S2 ret_from_syscall_function,B3,4 ;; Get syscall handler addr from sys_call_table ;; call tracesys_on or call syscall handler LDW .D1T1 *+A12(THREAD_INFO_FLAGS),A2 || MVKL .S2 sys_call_table,B1 MVKH .S2 sys_call_table,B1 LDW .D2T2 *+B1[B0],B0 NOP 2 ; A2 = thread_info flags AND .D1 _TIF_SYSCALL_TRACE,A2,A2 [A2] BNOP .S1 tracesys_on,5 ;; B0 = _sys_call_table[__NR_*] B .S2 B0 ADDKPC .S2 ret_from_syscall_function,B3,4 ret_from_syscall_function: STW .D2T1 A4,*+SP(REGS_A4+8) ; save return value in A4 ; original A4 is in orig_A4 syscall_exit: ;; make sure we don't miss an interrupt setting need_resched or ;; sigpending between sampling and the rti MASK_INT B2 LDW .D1T1 *+A12(THREAD_INFO_FLAGS),A2 MVK .S1 _TIF_ALLWORK_MASK,A1 NOP 3 AND .D1 A1,A2,A2 ; check for work to do [A2] BNOP .S1 syscall_exit_work,5 restore_all: RESTORE_ALL NRP,NTSR ;; ;; After a fork we jump here directly from resume, ;; so that A4 contains the previous task structure. ;; ENTRY(ret_from_fork) #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 schedule_tail,A0 MVKH .S1 schedule_tail,A0 B .S2X A0 #else B .S2 schedule_tail #endif ADDKPC .S2 ret_from_fork_2,B3,4 ret_from_fork_2: ;; return 0 in A4 for child process GET_THREAD_INFO A12 BNOP .S2 syscall_exit,3 MVK .L2 0,B0 STW .D2T2 B0,*+SP(REGS_A4+8) ENDPROC(ret_from_fork) ENTRY(ret_from_kernel_thread) #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 schedule_tail,A0 MVKH .S1 schedule_tail,A0 B .S2X A0 #else B .S2 schedule_tail #endif LDW .D2T2 *+SP(REGS_A0+8),B10 /* get fn */ ADDKPC .S2 0f,B3,3 0: B .S2 B10 /* call fn */ LDW .D2T1 *+SP(REGS_A1+8),A4 /* get arg */ ADDKPC .S2 ret_from_fork_2,B3,3 ENDPROC(ret_from_kernel_thread) ;; ;; These are the interrupt handlers, responsible for calling c6x_do_IRQ() ;; .macro SAVE_ALL_INT SAVE_ALL IRP,ITSR .endm .macro CALL_INT int #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 c6x_do_IRQ,A0 MVKH .S1 c6x_do_IRQ,A0 BNOP .S2X A0,1 MVK .S1 int,A4 ADDAW .D2 SP,2,B4 MVKL .S2 ret_from_interrupt,B3 MVKH .S2 ret_from_interrupt,B3 #else CALLP .S2 c6x_do_IRQ,B3 || MVK .S1 int,A4 || ADDAW .D2 SP,2,B4 B .S1 ret_from_interrupt NOP 5 #endif .endm ENTRY(_int4_handler) SAVE_ALL_INT CALL_INT 4 ENDPROC(_int4_handler) ENTRY(_int5_handler) SAVE_ALL_INT CALL_INT 5 ENDPROC(_int5_handler) ENTRY(_int6_handler) SAVE_ALL_INT CALL_INT 6 ENDPROC(_int6_handler) ENTRY(_int7_handler) SAVE_ALL_INT CALL_INT 7 ENDPROC(_int7_handler) ENTRY(_int8_handler) SAVE_ALL_INT CALL_INT 8 ENDPROC(_int8_handler) ENTRY(_int9_handler) SAVE_ALL_INT CALL_INT 9 ENDPROC(_int9_handler) ENTRY(_int10_handler) SAVE_ALL_INT CALL_INT 10 ENDPROC(_int10_handler) ENTRY(_int11_handler) SAVE_ALL_INT CALL_INT 11 ENDPROC(_int11_handler) ENTRY(_int12_handler) SAVE_ALL_INT CALL_INT 12 ENDPROC(_int12_handler) ENTRY(_int13_handler) SAVE_ALL_INT CALL_INT 13 ENDPROC(_int13_handler) ENTRY(_int14_handler) SAVE_ALL_INT CALL_INT 14 ENDPROC(_int14_handler) ENTRY(_int15_handler) SAVE_ALL_INT CALL_INT 15 ENDPROC(_int15_handler) ;; ;; Handler for uninitialized and spurious interrupts ;; ENTRY(_bad_interrupt) B .S2 IRP NOP 5 ENDPROC(_bad_interrupt) ;; ;; Entry for NMI/exceptions/syscall ;; ENTRY(_nmi_handler) SAVE_ALL NRP,NTSR MVC .S2 EFR,B2 CMPEQ .L2 1,B2,B2 || MVC .S2 TSR,B1 CLR .S2 B1,10,10,B1 MVC .S2 B1,TSR #ifdef CONFIG_C6X_BIG_KERNEL [!B2] MVKL .S1 process_exception,A0 [!B2] MVKH .S1 process_exception,A0 [!B2] B .S2X A0 #else [!B2] B .S2 process_exception #endif [B2] B .S2 system_call_saved [!B2] ADDAW .D2 SP,2,B1 [!B2] MV .D1X B1,A4 ADDKPC .S2 ret_from_trap,B3,2 ret_from_trap: MV .D2X A4,B0 [!B0] BNOP .S2 ret_from_exception,5 #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S2 system_call_saved_noack,B3 MVKH .S2 system_call_saved_noack,B3 #endif LDW .D2T2 *+SP(REGS_B0+8),B0 LDW .D2T1 *+SP(REGS_A4+8),A4 LDW .D2T2 *+SP(REGS_B4+8),B4 LDW .D2T1 *+SP(REGS_A6+8),A6 LDW .D2T2 *+SP(REGS_B6+8),B6 LDW .D2T1 *+SP(REGS_A8+8),A8 #ifdef CONFIG_C6X_BIG_KERNEL || B .S2 B3 #else || B .S2 system_call_saved_noack #endif LDW .D2T2 *+SP(REGS_B8+8),B8 NOP 4 ENDPROC(_nmi_handler) ;; ;; Jump to schedule() then return to ret_from_isr ;; #ifdef CONFIG_PREEMPT resume_kernel: GET_THREAD_INFO A12 LDW .D1T1 *+A12(THREAD_INFO_PREEMPT_COUNT),A1 NOP 4 [A1] BNOP .S2 restore_all,5 preempt_schedule: GET_THREAD_INFO A2 LDW .D1T1 *+A2(THREAD_INFO_FLAGS),A1 #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S2 preempt_schedule_irq,B0 MVKH .S2 preempt_schedule_irq,B0 NOP 2 #else NOP 4 #endif AND .D1 _TIF_NEED_RESCHED,A1,A1 [!A1] BNOP .S2 restore_all,5 #ifdef CONFIG_C6X_BIG_KERNEL B .S2 B0 #else B .S2 preempt_schedule_irq #endif ADDKPC .S2 preempt_schedule,B3,4 #endif /* CONFIG_PREEMPT */ ENTRY(enable_exception) DINT MVC .S2 TSR,B0 MVC .S2 B3,NRP MVK .L2 0xc,B1 OR .D2 B0,B1,B0 MVC .S2 B0,TSR ; Set GEE and XEN in TSR B .S2 NRP NOP 5 ENDPROC(enable_exception) ;; ;; Special system calls ;; return address is in B3 ;; ENTRY(sys_rt_sigreturn) ADD .D1X SP,8,A4 #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 do_rt_sigreturn,A0 MVKH .S1 do_rt_sigreturn,A0 BNOP .S2X A0,5 #else || B .S2 do_rt_sigreturn NOP 5 #endif ENDPROC(sys_rt_sigreturn) ENTRY(sys_pread_c6x) MV .D2X A8,B7 #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 sys_pread64,A0 MVKH .S1 sys_pread64,A0 BNOP .S2X A0,5 #else || B .S2 sys_pread64 NOP 5 #endif ENDPROC(sys_pread_c6x) ENTRY(sys_pwrite_c6x) MV .D2X A8,B7 #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 sys_pwrite64,A0 MVKH .S1 sys_pwrite64,A0 BNOP .S2X A0,5 #else || B .S2 sys_pwrite64 NOP 5 #endif ENDPROC(sys_pwrite_c6x) ;; On Entry ;; A4 - path ;; B4 - offset_lo (LE), offset_hi (BE) ;; A6 - offset_lo (BE), offset_hi (LE) ENTRY(sys_truncate64_c6x) #ifdef CONFIG_CPU_BIG_ENDIAN MV .S2 B4,B5 MV .D2X A6,B4 #else MV .D2X A6,B5 #endif #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 sys_truncate64,A0 MVKH .S1 sys_truncate64,A0 BNOP .S2X A0,5 #else || B .S2 sys_truncate64 NOP 5 #endif ENDPROC(sys_truncate64_c6x) ;; On Entry ;; A4 - fd ;; B4 - offset_lo (LE), offset_hi (BE) ;; A6 - offset_lo (BE), offset_hi (LE) ENTRY(sys_ftruncate64_c6x) #ifdef CONFIG_CPU_BIG_ENDIAN MV .S2 B4,B5 MV .D2X A6,B4 #else MV .D2X A6,B5 #endif #ifdef CONFIG_C6X_BIG_KERNEL || MVKL .S1 sys_ftruncate64,A0 MVKH .S1 sys_ftruncate64,A0 BNOP .S2X A0,5 #else || B .S2 sys_ftruncate64 NOP 5 #endif ENDPROC(sys_ftruncate64_c6x) ;; On Entry ;; A4 - fd ;; B4 - offset_lo (LE), offset_hi (BE) ;; A6 - offset_lo (BE), offset_hi (LE) ;; B6 - len_lo (LE), len_hi (BE) ;; A8 - len_lo (BE), len_hi (LE) ;; B8 - advice ENTRY(sys_fadvise64_64_c6x) #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 sys_fadvise64_64,A0 MVKH .S1 sys_fadvise64_64,A0 BNOP .S2X A0,2 #else B .S2 sys_fadvise64_64 NOP 2 #endif #ifdef CONFIG_CPU_BIG_ENDIAN MV .L2 B4,B5 || MV .D2X A6,B4 MV .L1 A8,A6 || MV .D1X B6,A7 #else MV .D2X A6,B5 MV .L1 A8,A7 || MV .D1X B6,A6 #endif MV .L2 B8,B6 ENDPROC(sys_fadvise64_64_c6x) ;; On Entry ;; A4 - fd ;; B4 - mode ;; A6 - offset_hi ;; B6 - offset_lo ;; A8 - len_hi ;; B8 - len_lo ENTRY(sys_fallocate_c6x) #ifdef CONFIG_C6X_BIG_KERNEL MVKL .S1 sys_fallocate,A0 MVKH .S1 sys_fallocate,A0 BNOP .S2X A0,1 #else B .S2 sys_fallocate NOP #endif MV .D1 A6,A7 MV .D1X B6,A6 MV .D2X A8,B7 MV .D2 B8,B6 ENDPROC(sys_fallocate_c6x) ;; put this in .neardata for faster access when using DSBT mode .section .neardata,"aw",@progbits .global current_ksp .hidden current_ksp current_ksp: .word init_thread_union + THREAD_START_SP