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-rw-r--r--arch/nds32/kernel/ex-entry.S157
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/nds32/kernel/ex-entry.S b/arch/nds32/kernel/ex-entry.S
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+++ b/arch/nds32/kernel/ex-entry.S
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+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/linkage.h>
+#include <asm/memory.h>
+#include <asm/nds32.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/page.h>
+
+#ifdef CONFIG_HWZOL
+ .macro push_zol
+ mfusr $r14, $LB
+ mfusr $r15, $LE
+ mfusr $r16, $LC
+ .endm
+#endif
+
+ .macro save_user_regs
+
+ smw.adm $sp, [$sp], $sp, #0x1
+ /* move $SP to the bottom of pt_regs */
+ addi $sp, $sp, -OSP_OFFSET
+
+ /* push $r0 ~ $r25 */
+ smw.bim $r0, [$sp], $r25
+ /* push $fp, $gp, $lp */
+ smw.bim $sp, [$sp], $sp, #0xe
+
+ mfsr $r12, $SP_USR
+ mfsr $r13, $IPC
+#ifdef CONFIG_HWZOL
+ push_zol
+#endif
+ movi $r17, -1
+ move $r18, $r0
+ mfsr $r19, $PSW
+ mfsr $r20, $IPSW
+ mfsr $r21, $P_IPSW
+ mfsr $r22, $P_IPC
+ mfsr $r23, $P_P0
+ mfsr $r24, $P_P1
+ smw.bim $r12, [$sp], $r24, #0
+ addi $sp, $sp, -FUCOP_CTL_OFFSET
+
+ /* Initialize kernel space $fp */
+ andi $p0, $r20, #PSW_mskPOM
+ movi $p1, #0x0
+ cmovz $fp, $p1, $p0
+
+ andi $r16, $r19, #PSW_mskINTL
+ slti $r17, $r16, #4
+ bnez $r17, 1f
+ addi $r17, $r19, #-2
+ mtsr $r17, $PSW
+ isb
+1:
+ /* If it was superuser mode, we don't need to update $r25 */
+ bnez $p0, 2f
+ la $p0, __entry_task
+ lw $r25, [$p0]
+2:
+ .endm
+
+ .text
+
+/*
+ * Exception Vector
+ */
+exception_handlers:
+ .long unhandled_exceptions !Reset/NMI
+ .long unhandled_exceptions !TLB fill
+ .long do_page_fault !PTE not present
+ .long do_dispatch_tlb_misc !TLB misc
+ .long unhandled_exceptions !TLB VLPT
+ .long unhandled_exceptions !Machine Error
+ .long do_debug_trap !Debug related
+ .long do_dispatch_general !General exception
+ .long eh_syscall !Syscall
+ .long asm_do_IRQ !IRQ
+
+common_exception_handler:
+ save_user_regs
+ mfsr $p0, $ITYPE
+ andi $p0, $p0, #ITYPE_mskVECTOR
+ srli $p0, $p0, #ITYPE_offVECTOR
+ andi $p1, $p0, #NDS32_VECTOR_mskNONEXCEPTION
+ bnez $p1, 1f
+ sethi $lp, hi20(ret_from_exception)
+ ori $lp, $lp, lo12(ret_from_exception)
+ sethi $p1, hi20(exception_handlers)
+ ori $p1, $p1, lo12(exception_handlers)
+ lw $p1, [$p1+$p0<<2]
+ move $r0, $p0
+ mfsr $r1, $EVA
+ mfsr $r2, $ITYPE
+ move $r3, $sp
+ mfsr $r4, $OIPC
+ /* enable gie if it is enabled in IPSW. */
+ mfsr $r21, $PSW
+ andi $r20, $r20, #PSW_mskGIE /* r20 is $IPSW*/
+ or $r21, $r21, $r20
+ mtsr $r21, $PSW
+ dsb
+ jr $p1
+
+ /* syscall */
+1:
+ addi $p1, $p0, #-NDS32_VECTOR_offEXCEPTION
+ bnez $p1, 2f
+ sethi $lp, hi20(ret_from_exception)
+ ori $lp, $lp, lo12(ret_from_exception)
+ sethi $p1, hi20(exception_handlers)
+ ori $p1, $p1, lo12(exception_handlers)
+ lwi $p1, [$p1+#NDS32_VECTOR_offEXCEPTION<<2]
+ jr $p1
+
+ /* interrupt */
+2:
+#ifdef CONFIG_TRACE_IRQFLAGS
+ jal __trace_hardirqs_off
+#endif
+ move $r0, $sp
+ sethi $lp, hi20(ret_from_intr)
+ ori $lp, $lp, lo12(ret_from_intr)
+ sethi $p0, hi20(exception_handlers)
+ ori $p0, $p0, lo12(exception_handlers)
+ lwi $p0, [$p0+#NDS32_VECTOR_offINTERRUPT<<2]
+ jr $p0
+
+ .macro EXCEPTION_VECTOR_DEBUG
+ .align 4
+ mfsr $p0, $EDM_CTL
+ andi $p0, $p0, EDM_CTL_mskV3_EDM_MODE
+ tnez $p0, SWID_RAISE_INTERRUPT_LEVEL
+ .endm
+
+ .macro EXCEPTION_VECTOR
+ .align 4
+ sethi $p0, hi20(common_exception_handler)
+ ori $p0, $p0, lo12(common_exception_handler)
+ jral.ton $p0, $p0
+ .endm
+
+ .section ".text.init", #alloc, #execinstr
+ .global exception_vector
+exception_vector:
+.rept 6
+ EXCEPTION_VECTOR
+.endr
+ EXCEPTION_VECTOR_DEBUG
+.rept 121
+ EXCEPTION_VECTOR
+.endr
+ .align 4
+ .global exception_vector_end
+exception_vector_end: