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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/mips/kernel/genex.S
Initial import
Diffstat (limited to 'arch/mips/kernel/genex.S')
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+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2002, 2007 Maciej W. Rozycki
+ * Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved.
+ */
+#include <linux/init.h>
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cacheops.h>
+#include <asm/irqflags.h>
+#include <asm/regdef.h>
+#include <asm/fpregdef.h>
+#include <asm/mipsregs.h>
+#include <asm/stackframe.h>
+#include <asm/war.h>
+#include <asm/thread_info.h>
+
+ __INIT
+
+/*
+ * General exception vector for all other CPUs.
+ *
+ * Be careful when changing this, it has to be at most 128 bytes
+ * to fit into space reserved for the exception handler.
+ */
+NESTED(except_vec3_generic, 0, sp)
+ .set push
+ .set noat
+#if R5432_CP0_INTERRUPT_WAR
+ mfc0 k0, CP0_INDEX
+#endif
+ mfc0 k1, CP0_CAUSE
+ andi k1, k1, 0x7c
+#ifdef CONFIG_64BIT
+ dsll k1, k1, 1
+#endif
+ PTR_L k0, exception_handlers(k1)
+ jr k0
+ .set pop
+ END(except_vec3_generic)
+
+/*
+ * General exception handler for CPUs with virtual coherency exception.
+ *
+ * Be careful when changing this, it has to be at most 256 (as a special
+ * exception) bytes to fit into space reserved for the exception handler.
+ */
+NESTED(except_vec3_r4000, 0, sp)
+ .set push
+ .set arch=r4000
+ .set noat
+ mfc0 k1, CP0_CAUSE
+ li k0, 31<<2
+ andi k1, k1, 0x7c
+ .set push
+ .set noreorder
+ .set nomacro
+ beq k1, k0, handle_vced
+ li k0, 14<<2
+ beq k1, k0, handle_vcei
+#ifdef CONFIG_64BIT
+ dsll k1, k1, 1
+#endif
+ .set pop
+ PTR_L k0, exception_handlers(k1)
+ jr k0
+
+ /*
+ * Big shit, we now may have two dirty primary cache lines for the same
+ * physical address. We can safely invalidate the line pointed to by
+ * c0_badvaddr because after return from this exception handler the
+ * load / store will be re-executed.
+ */
+handle_vced:
+ MFC0 k0, CP0_BADVADDR
+ li k1, -4 # Is this ...
+ and k0, k1 # ... really needed?
+ mtc0 zero, CP0_TAGLO
+ cache Index_Store_Tag_D, (k0)
+ cache Hit_Writeback_Inv_SD, (k0)
+#ifdef CONFIG_PROC_FS
+ PTR_LA k0, vced_count
+ lw k1, (k0)
+ addiu k1, 1
+ sw k1, (k0)
+#endif
+ eret
+
+handle_vcei:
+ MFC0 k0, CP0_BADVADDR
+ cache Hit_Writeback_Inv_SD, (k0) # also cleans pi
+#ifdef CONFIG_PROC_FS
+ PTR_LA k0, vcei_count
+ lw k1, (k0)
+ addiu k1, 1
+ sw k1, (k0)
+#endif
+ eret
+ .set pop
+ END(except_vec3_r4000)
+
+ __FINIT
+
+ .align 5 /* 32 byte rollback region */
+LEAF(__r4k_wait)
+ .set push
+ .set noreorder
+ /* start of rollback region */
+ LONG_L t0, TI_FLAGS($28)
+ nop
+ andi t0, _TIF_NEED_RESCHED
+ bnez t0, 1f
+ nop
+ nop
+ nop
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+ nop
+ nop
+ nop
+#endif
+ .set MIPS_ISA_ARCH_LEVEL_RAW
+ wait
+ /* end of rollback region (the region size must be power of two) */
+1:
+ jr ra
+ nop
+ .set pop
+ END(__r4k_wait)
+
+ .macro BUILD_ROLLBACK_PROLOGUE handler
+ FEXPORT(rollback_\handler)
+ .set push
+ .set noat
+ MFC0 k0, CP0_EPC
+ PTR_LA k1, __r4k_wait
+ ori k0, 0x1f /* 32 byte rollback region */
+ xori k0, 0x1f
+ bne k0, k1, 9f
+ MTC0 k0, CP0_EPC
+9:
+ .set pop
+ .endm
+
+ .align 5
+BUILD_ROLLBACK_PROLOGUE handle_int
+NESTED(handle_int, PT_SIZE, sp)
+#ifdef CONFIG_TRACE_IRQFLAGS
+ /*
+ * Check to see if the interrupted code has just disabled
+ * interrupts and ignore this interrupt for now if so.
+ *
+ * local_irq_disable() disables interrupts and then calls
+ * trace_hardirqs_off() to track the state. If an interrupt is taken
+ * after interrupts are disabled but before the state is updated
+ * it will appear to restore_all that it is incorrectly returning with
+ * interrupts disabled
+ */
+ .set push
+ .set noat
+ mfc0 k0, CP0_STATUS
+#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+ and k0, ST0_IEP
+ bnez k0, 1f
+
+ mfc0 k0, CP0_EPC
+ .set noreorder
+ j k0
+ rfe
+#else
+ and k0, ST0_IE
+ bnez k0, 1f
+
+ eret
+#endif
+1:
+ .set pop
+#endif
+ SAVE_ALL
+ CLI
+ TRACE_IRQS_OFF
+
+ LONG_L s0, TI_REGS($28)
+ LONG_S sp, TI_REGS($28)
+ PTR_LA ra, ret_from_irq
+ PTR_LA v0, plat_irq_dispatch
+ jr v0
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
+ END(handle_int)
+
+ __INIT
+
+/*
+ * Special interrupt vector for MIPS64 ISA & embedded MIPS processors.
+ * This is a dedicated interrupt exception vector which reduces the
+ * interrupt processing overhead. The jump instruction will be replaced
+ * at the initialization time.
+ *
+ * Be careful when changing this, it has to be at most 128 bytes
+ * to fit into space reserved for the exception handler.
+ */
+NESTED(except_vec4, 0, sp)
+1: j 1b /* Dummy, will be replaced */
+ END(except_vec4)
+
+/*
+ * EJTAG debug exception handler.
+ * The EJTAG debug exception entry point is 0xbfc00480, which
+ * normally is in the boot PROM, so the boot PROM must do an
+ * unconditional jump to this vector.
+ */
+NESTED(except_vec_ejtag_debug, 0, sp)
+ j ejtag_debug_handler
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
+ END(except_vec_ejtag_debug)
+
+ __FINIT
+
+/*
+ * Vectored interrupt handler.
+ * This prototype is copied to ebase + n*IntCtl.VS and patched
+ * to invoke the handler
+ */
+BUILD_ROLLBACK_PROLOGUE except_vec_vi
+NESTED(except_vec_vi, 0, sp)
+ SAVE_SOME
+ SAVE_AT
+ .set push
+ .set noreorder
+ PTR_LA v1, except_vec_vi_handler
+FEXPORT(except_vec_vi_lui)
+ lui v0, 0 /* Patched */
+ jr v1
+FEXPORT(except_vec_vi_ori)
+ ori v0, 0 /* Patched */
+ .set pop
+ END(except_vec_vi)
+EXPORT(except_vec_vi_end)
+
+/*
+ * Common Vectored Interrupt code
+ * Complete the register saves and invoke the handler which is passed in $v0
+ */
+NESTED(except_vec_vi_handler, 0, sp)
+ SAVE_TEMP
+ SAVE_STATIC
+ CLI
+#ifdef CONFIG_TRACE_IRQFLAGS
+ move s0, v0
+ TRACE_IRQS_OFF
+ move v0, s0
+#endif
+
+ LONG_L s0, TI_REGS($28)
+ LONG_S sp, TI_REGS($28)
+ PTR_LA ra, ret_from_irq
+ jr v0
+ END(except_vec_vi_handler)
+
+/*
+ * EJTAG debug exception handler.
+ */
+NESTED(ejtag_debug_handler, PT_SIZE, sp)
+ .set push
+ .set noat
+ MTC0 k0, CP0_DESAVE
+ mfc0 k0, CP0_DEBUG
+
+ sll k0, k0, 30 # Check for SDBBP.
+ bgez k0, ejtag_return
+
+ PTR_LA k0, ejtag_debug_buffer
+ LONG_S k1, 0(k0)
+ SAVE_ALL
+ move a0, sp
+ jal ejtag_exception_handler
+ RESTORE_ALL
+ PTR_LA k0, ejtag_debug_buffer
+ LONG_L k1, 0(k0)
+
+ejtag_return:
+ MFC0 k0, CP0_DESAVE
+ .set mips32
+ deret
+ .set pop
+ END(ejtag_debug_handler)
+
+/*
+ * This buffer is reserved for the use of the EJTAG debug
+ * handler.
+ */
+ .data
+EXPORT(ejtag_debug_buffer)
+ .fill LONGSIZE
+ .previous
+
+ __INIT
+
+/*
+ * NMI debug exception handler for MIPS reference boards.
+ * The NMI debug exception entry point is 0xbfc00000, which
+ * normally is in the boot PROM, so the boot PROM must do a
+ * unconditional jump to this vector.
+ */
+NESTED(except_vec_nmi, 0, sp)
+ j nmi_handler
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
+ END(except_vec_nmi)
+
+ __FINIT
+
+NESTED(nmi_handler, PT_SIZE, sp)
+ .set push
+ .set noat
+ /*
+ * Clear ERL - restore segment mapping
+ * Clear BEV - required for page fault exception handler to work
+ */
+ mfc0 k0, CP0_STATUS
+ ori k0, k0, ST0_EXL
+ li k1, ~(ST0_BEV | ST0_ERL)
+ and k0, k0, k1
+ mtc0 k0, CP0_STATUS
+ _ehb
+ SAVE_ALL
+ move a0, sp
+ jal nmi_exception_handler
+ /* nmi_exception_handler never returns */
+ .set pop
+ END(nmi_handler)
+
+ .macro __build_clear_none
+ .endm
+
+ .macro __build_clear_sti
+ TRACE_IRQS_ON
+ STI
+ .endm
+
+ .macro __build_clear_cli
+ CLI
+ TRACE_IRQS_OFF
+ .endm
+
+ .macro __build_clear_fpe
+ .set push
+ /* gas fails to assemble cfc1 for some archs (octeon).*/ \
+ .set mips1
+ SET_HARDFLOAT
+ cfc1 a1, fcr31
+ .set pop
+ CLI
+ TRACE_IRQS_OFF
+ .endm
+
+ .macro __build_clear_msa_fpe
+ _cfcmsa a1, MSA_CSR
+ CLI
+ TRACE_IRQS_OFF
+ .endm
+
+ .macro __build_clear_ade
+ MFC0 t0, CP0_BADVADDR
+ PTR_S t0, PT_BVADDR(sp)
+ KMODE
+ .endm
+
+ .macro __BUILD_silent exception
+ .endm
+
+ /* Gas tries to parse the PRINT argument as a string containing
+ string escapes and emits bogus warnings if it believes to
+ recognize an unknown escape code. So make the arguments
+ start with an n and gas will believe \n is ok ... */
+ .macro __BUILD_verbose nexception
+ LONG_L a1, PT_EPC(sp)
+#ifdef CONFIG_32BIT
+ PRINT("Got \nexception at %08lx\012")
+#endif
+#ifdef CONFIG_64BIT
+ PRINT("Got \nexception at %016lx\012")
+#endif
+ .endm
+
+ .macro __BUILD_count exception
+ LONG_L t0,exception_count_\exception
+ LONG_ADDIU t0, 1
+ LONG_S t0,exception_count_\exception
+ .comm exception_count\exception, 8, 8
+ .endm
+
+ .macro __BUILD_HANDLER exception handler clear verbose ext
+ .align 5
+ NESTED(handle_\exception, PT_SIZE, sp)
+ .set noat
+ SAVE_ALL
+ FEXPORT(handle_\exception\ext)
+ __BUILD_clear_\clear
+ .set at
+ __BUILD_\verbose \exception
+ move a0, sp
+ PTR_LA ra, ret_from_exception
+ j do_\handler
+ END(handle_\exception)
+ .endm
+
+ .macro BUILD_HANDLER exception handler clear verbose
+ __BUILD_HANDLER \exception \handler \clear \verbose _int
+ .endm
+
+ BUILD_HANDLER adel ade ade silent /* #4 */
+ BUILD_HANDLER ades ade ade silent /* #5 */
+ BUILD_HANDLER ibe be cli silent /* #6 */
+ BUILD_HANDLER dbe be cli silent /* #7 */
+ BUILD_HANDLER bp bp sti silent /* #9 */
+ BUILD_HANDLER ri ri sti silent /* #10 */
+ BUILD_HANDLER cpu cpu sti silent /* #11 */
+ BUILD_HANDLER ov ov sti silent /* #12 */
+ BUILD_HANDLER tr tr sti silent /* #13 */
+ BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
+ BUILD_HANDLER fpe fpe fpe silent /* #15 */
+ BUILD_HANDLER ftlb ftlb none silent /* #16 */
+ BUILD_HANDLER msa msa sti silent /* #21 */
+ BUILD_HANDLER mdmx mdmx sti silent /* #22 */
+#ifdef CONFIG_HARDWARE_WATCHPOINTS
+ /*
+ * For watch, interrupts will be enabled after the watch
+ * registers are read.
+ */
+ BUILD_HANDLER watch watch cli silent /* #23 */
+#else
+ BUILD_HANDLER watch watch sti verbose /* #23 */
+#endif
+ BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
+ BUILD_HANDLER mt mt sti silent /* #25 */
+ BUILD_HANDLER dsp dsp sti silent /* #26 */
+ BUILD_HANDLER reserved reserved sti verbose /* others */
+
+ .align 5
+ LEAF(handle_ri_rdhwr_vivt)
+ .set push
+ .set noat
+ .set noreorder
+ /* check if TLB contains a entry for EPC */
+ MFC0 k1, CP0_ENTRYHI
+ andi k1, 0xff /* ASID_MASK */
+ MFC0 k0, CP0_EPC
+ PTR_SRL k0, _PAGE_SHIFT + 1
+ PTR_SLL k0, _PAGE_SHIFT + 1
+ or k1, k0
+ MTC0 k1, CP0_ENTRYHI
+ mtc0_tlbw_hazard
+ tlbp
+ tlb_probe_hazard
+ mfc0 k1, CP0_INDEX
+ .set pop
+ bltz k1, handle_ri /* slow path */
+ /* fall thru */
+ END(handle_ri_rdhwr_vivt)
+
+ LEAF(handle_ri_rdhwr)
+ .set push
+ .set noat
+ .set noreorder
+ /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
+ /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
+ MFC0 k1, CP0_EPC
+#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
+ and k0, k1, 1
+ beqz k0, 1f
+ xor k1, k0
+ lhu k0, (k1)
+ lhu k1, 2(k1)
+ ins k1, k0, 16, 16
+ lui k0, 0x007d
+ b docheck
+ ori k0, 0x6b3c
+1:
+ lui k0, 0x7c03
+ lw k1, (k1)
+ ori k0, 0xe83b
+#else
+ andi k0, k1, 1
+ bnez k0, handle_ri
+ lui k0, 0x7c03
+ lw k1, (k1)
+ ori k0, 0xe83b
+#endif
+ .set reorder
+docheck:
+ bne k0, k1, handle_ri /* if not ours */
+
+isrdhwr:
+ /* The insn is rdhwr. No need to check CAUSE.BD here. */
+ get_saved_sp /* k1 := current_thread_info */
+ .set noreorder
+ MFC0 k0, CP0_EPC
+#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+ ori k1, _THREAD_MASK
+ xori k1, _THREAD_MASK
+ LONG_L v1, TI_TP_VALUE(k1)
+ LONG_ADDIU k0, 4
+ jr k0
+ rfe
+#else
+#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
+ LONG_ADDIU k0, 4 /* stall on $k0 */
+#else
+ .set at=v1
+ LONG_ADDIU k0, 4
+ .set noat
+#endif
+ MTC0 k0, CP0_EPC
+ /* I hope three instructions between MTC0 and ERET are enough... */
+ ori k1, _THREAD_MASK
+ xori k1, _THREAD_MASK
+ LONG_L v1, TI_TP_VALUE(k1)
+ .set arch=r4000
+ eret
+ .set mips0
+#endif
+ .set pop
+ END(handle_ri_rdhwr)
+
+#ifdef CONFIG_64BIT
+/* A temporary overflow handler used by check_daddi(). */
+
+ __INIT
+
+ BUILD_HANDLER daddi_ov daddi_ov none silent /* #12 */
+#endif