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-rw-r--r--arch/sh/kernel/cpu/sh2/entry.S373
1 files changed, 373 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/sh2/entry.S b/arch/sh/kernel/cpu/sh2/entry.S
new file mode 100644
index 000000000..0a1c2bf21
--- /dev/null
+++ b/arch/sh/kernel/cpu/sh2/entry.S
@@ -0,0 +1,373 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * arch/sh/kernel/cpu/sh2/entry.S
+ *
+ * The SH-2 exception entry
+ *
+ * Copyright (C) 2005-2008 Yoshinori Sato
+ * Copyright (C) 2005 AXE,Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <cpu/mmu_context.h>
+#include <asm/unistd.h>
+#include <asm/errno.h>
+#include <asm/page.h>
+
+/* Offsets to the stack */
+OFF_R0 = 0 /* Return value. New ABI also arg4 */
+OFF_R1 = 4 /* New ABI: arg5 */
+OFF_R2 = 8 /* New ABI: arg6 */
+OFF_R3 = 12 /* New ABI: syscall_nr */
+OFF_R4 = 16 /* New ABI: arg0 */
+OFF_R5 = 20 /* New ABI: arg1 */
+OFF_R6 = 24 /* New ABI: arg2 */
+OFF_R7 = 28 /* New ABI: arg3 */
+OFF_SP = (15*4)
+OFF_PC = (16*4)
+OFF_SR = (16*4+2*4)
+OFF_TRA = (16*4+6*4)
+
+#include <asm/entry-macros.S>
+
+ENTRY(exception_handler)
+ ! stack
+ ! r0 <- point sp
+ ! r1
+ ! pc
+ ! sr
+ ! r0 = temporary
+ ! r1 = vector (pseudo EXPEVT / INTEVT / TRA)
+ mov.l r2,@-sp
+ mov.l r3,@-sp
+ cli
+ mov.l $cpu_mode,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r2
+#endif
+ mov.l @r2,r0
+ mov.l @(5*4,r15),r3 ! previous SR
+ or r0,r3 ! set MD
+ tst r0,r0
+ bf/s 1f ! previous mode check
+ mov.l r3,@(5*4,r15) ! update SR
+ ! switch to kernel mode
+ mov.l __md_bit,r0
+ mov.l r0,@r2 ! enter kernel mode
+ mov.l $current_thread_info,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r0
+ mov.l @r0,r0
+ mov.l @r0,r0
+ shll2 r0
+ add r0,r2
+#endif
+ mov.l @r2,r2
+ mov #(THREAD_SIZE >> 8),r0
+ shll8 r0
+ add r2,r0
+ mov r15,r2 ! r2 = user stack top
+ mov r0,r15 ! switch kernel stack
+ mov.l r1,@-r15 ! TRA
+ sts.l macl, @-r15
+ sts.l mach, @-r15
+ stc.l gbr, @-r15
+ mov.l @(5*4,r2),r0
+ mov.l r0,@-r15 ! original SR
+ sts.l pr,@-r15
+ mov.l @(4*4,r2),r0
+ mov.l r0,@-r15 ! original PC
+ mov r2,r3
+ add #(4+2)*4,r3 ! rewind r0 - r3 + exception frame
+ mov.l r3,@-r15 ! original SP
+ mov.l r14,@-r15
+ mov.l r13,@-r15
+ mov.l r12,@-r15
+ mov.l r11,@-r15
+ mov.l r10,@-r15
+ mov.l r9,@-r15
+ mov.l r8,@-r15
+ mov.l r7,@-r15
+ mov.l r6,@-r15
+ mov.l r5,@-r15
+ mov.l r4,@-r15
+ mov r1,r9 ! save TRA
+ mov r2,r8 ! copy user -> kernel stack
+ mov.l @(0,r8),r3
+ mov.l r3,@-r15
+ mov.l @(4,r8),r2
+ mov.l r2,@-r15
+ mov.l @(12,r8),r1
+ mov.l r1,@-r15
+ mov.l @(8,r8),r0
+ bra 2f
+ mov.l r0,@-r15
+1:
+ ! in kernel exception
+ mov #(22-4-4-1)*4+4,r0
+ mov r15,r2
+ sub r0,r15
+ mov.l @r2+,r0 ! old R3
+ mov.l r0,@-r15
+ mov.l @r2+,r0 ! old R2
+ mov.l r0,@-r15
+ mov.l @(4,r2),r0 ! old R1
+ mov.l r0,@-r15
+ mov.l @r2,r0 ! old R0
+ mov.l r0,@-r15
+ add #8,r2
+ mov.l @r2+,r3 ! old PC
+ mov.l @r2+,r0 ! old SR
+ add #-4,r2 ! exception frame stub (sr)
+ mov.l r1,@-r2 ! TRA
+ sts.l macl, @-r2
+ sts.l mach, @-r2
+ stc.l gbr, @-r2
+ mov.l r0,@-r2 ! save old SR
+ sts.l pr,@-r2
+ mov.l r3,@-r2 ! save old PC
+ mov r2,r0
+ add #8*4,r0
+ mov.l r0,@-r2 ! save old SP
+ mov.l r14,@-r2
+ mov.l r13,@-r2
+ mov.l r12,@-r2
+ mov.l r11,@-r2
+ mov.l r10,@-r2
+ mov.l r9,@-r2
+ mov.l r8,@-r2
+ mov.l r7,@-r2
+ mov.l r6,@-r2
+ mov.l r5,@-r2
+ mov.l r4,@-r2
+ mov r1,r9
+ mov.l @(OFF_R0,r15),r0
+ mov.l @(OFF_R1,r15),r1
+ mov.l @(OFF_R2,r15),r2
+ mov.l @(OFF_R3,r15),r3
+2:
+ mov #64,r8
+ cmp/hs r8,r9
+ bt interrupt_entry ! vec >= 64 is interrupt
+ mov #31,r8
+ cmp/hs r8,r9
+ bt trap_entry ! 64 > vec >= 31 is trap
+#ifdef CONFIG_CPU_J2
+ mov #16,r8
+ cmp/hs r8,r9
+ bt interrupt_entry ! 31 > vec >= 16 is interrupt
+#endif
+
+ mov.l 4f,r8
+ mov r9,r4
+ shll2 r9
+ add r9,r8
+ mov.l @r8,r8 ! exception handler address
+ tst r8,r8
+ bf 3f
+ mov.l 8f,r8 ! unhandled exception
+3:
+ mov.l 5f,r10
+ jmp @r8
+ lds r10,pr
+
+interrupt_entry:
+ mov r9,r4
+ mov r15,r5
+ mov.l 6f,r9
+ mov.l 7f,r8
+ jmp @r8
+ lds r9,pr
+
+ .align 2
+4: .long exception_handling_table
+5: .long ret_from_exception
+6: .long ret_from_irq
+7: .long do_IRQ
+8: .long exception_error
+
+trap_entry:
+ mov #0x30,r8
+ cmp/ge r8,r9 ! vector 0x1f-0x2f is systemcall
+ bt 1f
+ mov #0x1f,r9 ! convert to unified SH2/3/4 trap number
+1:
+ shll2 r9 ! TRA
+ bra system_call ! jump common systemcall entry
+ mov r9,r8
+
+#if defined(CONFIG_SH_STANDARD_BIOS)
+ /* Unwind the stack and jmp to the debug entry */
+ENTRY(sh_bios_handler)
+ mov r15,r0
+ add #(22-4)*4-4,r0
+ ldc.l @r0+,gbr
+ lds.l @r0+,mach
+ lds.l @r0+,macl
+ mov r15,r0
+ mov.l @(OFF_SP,r0),r1
+ mov #OFF_SR,r2
+ mov.l @(r0,r2),r3
+ mov.l r3,@-r1
+ mov #OFF_SP,r2
+ mov.l @(r0,r2),r3
+ mov.l r3,@-r1
+ mov r15,r0
+ add #(22-4)*4-8,r0
+ mov.l 1f,r2
+ mov.l @r2,r2
+ stc sr,r3
+ mov.l r2,@r0
+ mov.l r3,@(4,r0)
+ mov.l r1,@(8,r0)
+ mov.l @r15+, r0
+ mov.l @r15+, r1
+ mov.l @r15+, r2
+ mov.l @r15+, r3
+ mov.l @r15+, r4
+ mov.l @r15+, r5
+ mov.l @r15+, r6
+ mov.l @r15+, r7
+ mov.l @r15+, r8
+ mov.l @r15+, r9
+ mov.l @r15+, r10
+ mov.l @r15+, r11
+ mov.l @r15+, r12
+ mov.l @r15+, r13
+ mov.l @r15+, r14
+ add #8,r15
+ lds.l @r15+, pr
+ mov.l @r15+,r15
+ rte
+ nop
+ .align 2
+1: .long gdb_vbr_vector
+#endif /* CONFIG_SH_STANDARD_BIOS */
+
+ENTRY(address_error_trap_handler)
+ mov r15,r4 ! regs
+ mov #OFF_PC,r0
+ mov.l @(r0,r15),r6 ! pc
+ mov.l 1f,r0
+ jmp @r0
+ mov #0,r5 ! writeaccess is unknown
+
+ .align 2
+1: .long do_address_error
+
+restore_all:
+ stc sr,r0
+ or #0xf0,r0
+ ldc r0,sr ! all interrupt block (same BL = 1)
+ ! restore special register
+ ! overlap exception frame
+ mov r15,r0
+ add #17*4,r0
+ lds.l @r0+,pr
+ add #4,r0
+ ldc.l @r0+,gbr
+ lds.l @r0+,mach
+ lds.l @r0+,macl
+ mov r15,r0
+ mov.l $cpu_mode,r2
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r2
+#endif
+ mov #OFF_SR,r3
+ mov.l @(r0,r3),r1
+ mov.l __md_bit,r3
+ and r1,r3 ! copy MD bit
+ mov.l r3,@r2
+ shll2 r1 ! clear MD bit
+ shlr2 r1
+ mov.l @(OFF_SP,r0),r2
+ add #-8,r2
+ mov.l r2,@(OFF_SP,r0) ! point exception frame top
+ mov.l r1,@(4,r2) ! set sr
+ mov #OFF_PC,r3
+ mov.l @(r0,r3),r1
+ mov.l r1,@r2 ! set pc
+ get_current_thread_info r0, r1
+ mov.l $current_thread_info,r1
+#ifdef CONFIG_SMP
+ mov.l $cpuid,r3
+ mov.l @r3,r3
+ mov.l @r3,r3
+ shll2 r3
+ add r3,r1
+#endif
+ mov.l r0,@r1
+ mov.l @r15+,r0
+ mov.l @r15+,r1
+ mov.l @r15+,r2
+ mov.l @r15+,r3
+ mov.l @r15+,r4
+ mov.l @r15+,r5
+ mov.l @r15+,r6
+ mov.l @r15+,r7
+ mov.l @r15+,r8
+ mov.l @r15+,r9
+ mov.l @r15+,r10
+ mov.l @r15+,r11
+ mov.l @r15+,r12
+ mov.l @r15+,r13
+ mov.l @r15+,r14
+ mov.l @r15,r15
+ rte
+ nop
+
+ .align 2
+__md_bit:
+ .long 0x40000000
+$current_thread_info:
+ .long __current_thread_info
+$cpu_mode:
+ .long __cpu_mode
+#ifdef CONFIG_SMP
+$cpuid:
+ .long sh2_cpuid_addr
+#endif
+
+! common exception handler
+#include "../../entry-common.S"
+
+#ifdef CONFIG_NR_CPUS
+#define NR_CPUS CONFIG_NR_CPUS
+#else
+#define NR_CPUS 1
+#endif
+
+ .data
+! cpu operation mode
+! bit30 = MD (compatible SH3/4)
+__cpu_mode:
+ .rept NR_CPUS
+ .long 0x40000000
+ .endr
+
+#ifdef CONFIG_SMP
+.global sh2_cpuid_addr
+sh2_cpuid_addr:
+ .long dummy_cpuid
+dummy_cpuid:
+ .long 0
+#endif
+
+ .section .bss
+__current_thread_info:
+ .rept NR_CPUS
+ .long 0
+ .endr
+
+ENTRY(exception_handling_table)
+ .space 4*32