diff options
Diffstat (limited to 'arch/arc/include/asm/entry-arcv2.h')
| -rw-r--r-- | arch/arc/include/asm/entry-arcv2.h | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/arc/include/asm/entry-arcv2.h b/arch/arc/include/asm/entry-arcv2.h new file mode 100644 index 000000000000..b5ff87e6f4b7 --- /dev/null +++ b/arch/arc/include/asm/entry-arcv2.h @@ -0,0 +1,190 @@ + +#ifndef __ASM_ARC_ENTRY_ARCV2_H +#define __ASM_ARC_ENTRY_ARCV2_H + +#include <asm/asm-offsets.h> +#include <asm/irqflags-arcv2.h> +#include <asm/thread_info.h> /* For THREAD_SIZE */ + +/*------------------------------------------------------------------------*/ +.macro INTERRUPT_PROLOGUE called_from + + ; Before jumping to Interrupt Vector, hardware micro-ops did following: + ; 1. SP auto-switched to kernel mode stack + ; 2. STATUS32.Z flag set to U mode at time of interrupt (U:1, K:0) + ; 3. Auto saved: r0-r11, blink, LPE,LPS,LPC, JLI,LDI,EI, PC, STAT32 + ; + ; Now manually save: r12, sp, fp, gp, r25 + + PUSH r12 + + ; Saving pt_regs->sp correctly requires some extra work due to the way + ; Auto stack switch works + ; - U mode: retrieve it from AUX_USER_SP + ; - K mode: add the offset from current SP where H/w starts auto push + ; + ; Utilize the fact that Z bit is set if Intr taken in U mode + mov.nz r9, sp + add.nz r9, r9, SZ_PT_REGS - PT_sp - 4 + bnz 1f + + lr r9, [AUX_USER_SP] +1: + PUSH r9 ; SP + + PUSH fp + PUSH gp + +#ifdef CONFIG_ARC_CURR_IN_REG + PUSH r25 ; user_r25 + GET_CURR_TASK_ON_CPU r25 +#else + sub sp, sp, 4 +#endif + +.ifnc \called_from, exception + sub sp, sp, 12 ; BTA/ECR/orig_r0 placeholder per pt_regs +.endif + +.endm + +/*------------------------------------------------------------------------*/ +.macro INTERRUPT_EPILOGUE called_from + +.ifnc \called_from, exception + add sp, sp, 12 ; skip BTA/ECR/orig_r0 placeholderss +.endif + +#ifdef CONFIG_ARC_CURR_IN_REG + POP r25 +#else + add sp, sp, 4 +#endif + + POP gp + POP fp + + ; Don't touch AUX_USER_SP if returning to K mode (Z bit set) + ; (Z bit set on K mode is inverse of INTERRUPT_PROLOGUE) + add.z sp, sp, 4 + bz 1f + + POPAX AUX_USER_SP +1: + POP r12 + +.endm + +/*------------------------------------------------------------------------*/ +.macro EXCEPTION_PROLOGUE + + ; Before jumping to Exception Vector, hardware micro-ops did following: + ; 1. SP auto-switched to kernel mode stack + ; 2. STATUS32.Z flag set to U mode at time of interrupt (U:1,K:0) + ; + ; Now manually save the complete reg file + + PUSH r9 ; freeup a register: slot of erstatus + + PUSHAX eret + sub sp, sp, 12 ; skip JLI, LDI, EI + PUSH lp_count + PUSHAX lp_start + PUSHAX lp_end + PUSH blink + + PUSH r11 + PUSH r10 + + ld.as r9, [sp, 10] ; load stashed r9 (status32 stack slot) + lr r10, [erstatus] + st.as r10, [sp, 10] ; save status32 at it's right stack slot + + PUSH r9 + PUSH r8 + PUSH r7 + PUSH r6 + PUSH r5 + PUSH r4 + PUSH r3 + PUSH r2 + PUSH r1 + PUSH r0 + + ; -- for interrupts, regs above are auto-saved by h/w in that order -- + ; Now do what ISR prologue does (manually save r12, sp, fp, gp, r25) + ; + ; Set Z flag if this was from U mode (expected by INTERRUPT_PROLOGUE) + ; Although H/w exception micro-ops do set Z flag for U mode (just like + ; for interrupts), it could get clobbered in case we soft land here from + ; a TLB Miss exception handler (tlbex.S) + + and r10, r10, STATUS_U_MASK + xor.f 0, r10, STATUS_U_MASK + + INTERRUPT_PROLOGUE exception + + PUSHAX erbta + PUSHAX ecr ; r9 contains ECR, expected by EV_Trap + + PUSH r0 ; orig_r0 +.endm + +/*------------------------------------------------------------------------*/ +.macro EXCEPTION_EPILOGUE + + ; Assumes r0 has PT_status32 + btst r0, STATUS_U_BIT ; Z flag set if K, used in INTERRUPT_EPILOGUE + + add sp, sp, 8 ; orig_r0/ECR don't need restoring + POPAX erbta + + INTERRUPT_EPILOGUE exception + + POP r0 + POP r1 + POP r2 + POP r3 + POP r4 + POP r5 + POP r6 + POP r7 + POP r8 + POP r9 + POP r10 + POP r11 + + POP blink + POPAX lp_end + POPAX lp_start + + POP r9 + mov lp_count, r9 + + add sp, sp, 12 ; skip JLI, LDI, EI + POPAX eret + POPAX erstatus + + ld.as r9, [sp, -12] ; reload r9 which got clobbered +.endm + +.macro FAKE_RET_FROM_EXCPN + lr r9, [status32] + bic r9, r9, (STATUS_U_MASK|STATUS_DE_MASK|STATUS_AE_MASK) + or r9, r9, (STATUS_L_MASK|STATUS_IE_MASK) + kflag r9 +.endm + +/* Get thread_info of "current" tsk */ +.macro GET_CURR_THR_INFO_FROM_SP reg + bmskn \reg, sp, THREAD_SHIFT - 1 +.endm + +/* Get CPU-ID of this core */ +.macro GET_CPU_ID reg + lr \reg, [identity] + xbfu \reg, \reg, 0xE8 /* 00111 01000 */ + /* M = 8-1 N = 8 */ +.endm + +#endif |