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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
commite5fd91f1ef340da553f7a79da9540c3db711c937 (patch)
treeb11842027dc6641da63f4bcc524f8678263304a3 /arch/arc/include/asm/entry-arcv2.h
parent2a9b0348e685a63d97486f6749622b61e9e3292f (diff)
Linux-libre 4.2-gnu
Diffstat (limited to 'arch/arc/include/asm/entry-arcv2.h')
-rw-r--r--arch/arc/include/asm/entry-arcv2.h190
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 000000000..b5ff87e6f
--- /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