]> git.ipfire.org Git - people/ms/u-boot.git/blobdiff - cpu/ppc4xx/start.S
ppc4xx: Clean up 440 exceptions handling
[people/ms/u-boot.git] / cpu / ppc4xx / start.S
index 78d0042cc76b6d788ad9d705062b77a599bdcafa..e135220f6d00b59f4657c65765a9e983149f2ec4 100644 (file)
@@ -294,11 +294,13 @@ skip_debug_init:
        mtspr   ivor7,r1        /* Floating point unavailable */
        li      r1,0x0c00
        mtspr   ivor8,r1        /* System call */
-       li      r1,0x1000
-       mtspr   ivor10,r1       /* Decrementer (PIT for 440) */
-       li      r1,0x1400
-       mtspr   ivor13,r1       /* Data TLB error */
+       li      r1,0x0a00
+       mtspr   ivor9,r1        /* Auxiliary Processor unavailable */
+       li      r1,0x0900
+       mtspr   ivor10,r1       /* Decrementer */
        li      r1,0x1300
+       mtspr   ivor13,r1       /* Data TLB error */
+       li      r1,0x1400
        mtspr   ivor14,r1       /* Instr TLB error */
        li      r1,0x2000
        mtspr   ivor15,r1       /* Debug */
@@ -503,11 +505,81 @@ version_string:
        .ascii " (", __DATE__, " - ", __TIME__, ")"
        .ascii CONFIG_IDENT_STRING, "\0"
 
-/*
- * Maybe this should be moved somewhere else because the current
- * location (0x100) is where the CriticalInput Execption should be.
- */
        . = EXC_OFF_SYS_RESET
+       .globl  _start_of_vectors
+_start_of_vectors:
+
+/* Critical input. */
+       CRIT_EXCEPTION(0x100, CritcalInput, UnknownException)
+
+#ifdef CONFIG_440
+/* Machine check */
+        MCK_EXCEPTION(0x200, MachineCheck, MachineCheckException)
+#else
+        CRIT_EXCEPTION(0x200, MachineCheck, MachineCheckException)
+#endif /* CONFIG_440 */
+
+/* Data Storage exception. */
+       STD_EXCEPTION(0x300, DataStorage, UnknownException)
+
+/* Instruction Storage exception. */
+       STD_EXCEPTION(0x400, InstStorage, UnknownException)
+
+/* External Interrupt exception. */
+       STD_EXCEPTION(0x500, ExtInterrupt, external_interrupt)
+
+/* Alignment exception. */
+       . = 0x600
+Alignment:
+       EXCEPTION_PROLOG(SRR0, SRR1)
+       mfspr   r4,DAR
+       stw     r4,_DAR(r21)
+       mfspr   r5,DSISR
+       stw     r5,_DSISR(r21)
+       addi    r3,r1,STACK_FRAME_OVERHEAD
+       li      r20,MSR_KERNEL
+       rlwimi  r20,r23,0,16,16         /* copy EE bit from saved MSR */
+       lwz     r6,GOT(transfer_to_handler)
+       mtlr    r6
+       blrl
+.L_Alignment:
+       .long   AlignmentException - _start + _START_OFFSET
+       .long   int_return - _start + _START_OFFSET
+
+/* Program check exception */
+       . = 0x700
+ProgramCheck:
+       EXCEPTION_PROLOG(SRR0, SRR1)
+       addi    r3,r1,STACK_FRAME_OVERHEAD
+       li      r20,MSR_KERNEL
+       rlwimi  r20,r23,0,16,16         /* copy EE bit from saved MSR */
+       lwz     r6,GOT(transfer_to_handler)
+       mtlr    r6
+       blrl
+.L_ProgramCheck:
+       .long   ProgramCheckException - _start + _START_OFFSET
+       .long   int_return - _start + _START_OFFSET
+
+#ifdef CONFIG_440
+       STD_EXCEPTION(0x800, FPUnavailable, UnknownException)
+       STD_EXCEPTION(0x900, Decrementer, DecrementerPITException)
+       STD_EXCEPTION(0xa00, APU, UnknownException)
+#endif 
+       STD_EXCEPTION(0xc00, SystemCall, UnknownException)
+
+#ifdef CONFIG_440
+       STD_EXCEPTION(0x1300, DataTLBError, UnknownException)
+       STD_EXCEPTION(0x1400, InstructionTLBError, UnknownException)
+#else
+       STD_EXCEPTION(0x1000, PIT, DecrementerPITException)
+       STD_EXCEPTION(0x1100, InstructionTLBMiss, UnknownException)
+       STD_EXCEPTION(0x1200, DataTLBMiss, UnknownException)
+#endif
+       CRIT_EXCEPTION(0x2000, DebugBreakpoint, DebugException )
+
+       .globl  _end_of_vectors
+_end_of_vectors:
+       . = _START_OFFSET
 #endif
        .globl  _start
 _start:
@@ -1017,107 +1089,6 @@ start_ram:
 
 
 #ifndef CONFIG_NAND_SPL
-/*****************************************************************************/
-       .globl  _start_of_vectors
-_start_of_vectors:
-
-#if 0
-/*TODO Fixup _start above so we can do this*/
-/* Critical input. */
-       CRIT_EXCEPTION(0x100, CritcalInput, CritcalInputException)
-#endif
-
-/* Machine check */
-       CRIT_EXCEPTION(0x200, MachineCheck, MachineCheckException)
-
-/* Data Storage exception. */
-       STD_EXCEPTION(0x300, DataStorage, UnknownException)
-
-/* Instruction Storage exception. */
-       STD_EXCEPTION(0x400, InstStorage, UnknownException)
-
-/* External Interrupt exception. */
-       STD_EXCEPTION(0x500, ExtInterrupt, external_interrupt)
-
-/* Alignment exception. */
-       . = 0x600
-Alignment:
-       EXCEPTION_PROLOG
-       mfspr   r4,DAR
-       stw     r4,_DAR(r21)
-       mfspr   r5,DSISR
-       stw     r5,_DSISR(r21)
-       addi    r3,r1,STACK_FRAME_OVERHEAD
-       li      r20,MSR_KERNEL
-       rlwimi  r20,r23,0,16,16         /* copy EE bit from saved MSR */
-       lwz     r6,GOT(transfer_to_handler)
-       mtlr    r6
-       blrl
-.L_Alignment:
-       .long   AlignmentException - _start + EXC_OFF_SYS_RESET
-       .long   int_return - _start + EXC_OFF_SYS_RESET
-
-/* Program check exception */
-       . = 0x700
-ProgramCheck:
-       EXCEPTION_PROLOG
-       addi    r3,r1,STACK_FRAME_OVERHEAD
-       li      r20,MSR_KERNEL
-       rlwimi  r20,r23,0,16,16         /* copy EE bit from saved MSR */
-       lwz     r6,GOT(transfer_to_handler)
-       mtlr    r6
-       blrl
-.L_ProgramCheck:
-       .long   ProgramCheckException - _start + EXC_OFF_SYS_RESET
-       .long   int_return - _start + EXC_OFF_SYS_RESET
-
-       /* No FPU on MPC8xx.  This exception is not supposed to happen.
-       */
-       STD_EXCEPTION(0x800, FPUnavailable, UnknownException)
-
-       /* I guess we could implement decrementer, and may have
-        * to someday for timekeeping.
-        */
-       STD_EXCEPTION(0x900, Decrementer, timer_interrupt)
-       STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
-       STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
-       STD_EXCEPTION(0xc00, SystemCall, UnknownException)
-       STD_EXCEPTION(0xd00, SingleStep, UnknownException)
-
-       STD_EXCEPTION(0xe00, Trap_0e, UnknownException)
-       STD_EXCEPTION(0xf00, Trap_0f, UnknownException)
-
-       /* On the MPC8xx, this is a software emulation interrupt.  It occurs
-        * for all unimplemented and illegal instructions.
-        */
-       STD_EXCEPTION(0x1000, PIT, PITException)
-
-       STD_EXCEPTION(0x1100, InstructionTLBMiss, UnknownException)
-       STD_EXCEPTION(0x1200, DataTLBMiss, UnknownException)
-       STD_EXCEPTION(0x1300, InstructionTLBError, UnknownException)
-       STD_EXCEPTION(0x1400, DataTLBError, UnknownException)
-
-       STD_EXCEPTION(0x1500, Reserved5, UnknownException)
-       STD_EXCEPTION(0x1600, Reserved6, UnknownException)
-       STD_EXCEPTION(0x1700, Reserved7, UnknownException)
-       STD_EXCEPTION(0x1800, Reserved8, UnknownException)
-       STD_EXCEPTION(0x1900, Reserved9, UnknownException)
-       STD_EXCEPTION(0x1a00, ReservedA, UnknownException)
-       STD_EXCEPTION(0x1b00, ReservedB, UnknownException)
-
-       STD_EXCEPTION(0x1c00, DataBreakpoint, UnknownException)
-       STD_EXCEPTION(0x1d00, InstructionBreakpoint, UnknownException)
-       STD_EXCEPTION(0x1e00, PeripheralBreakpoint, UnknownException)
-       STD_EXCEPTION(0x1f00, DevPortBreakpoint, UnknownException)
-
-       CRIT_EXCEPTION(0x2000, DebugBreakpoint, DebugException )
-
-       .globl  _end_of_vectors
-_end_of_vectors:
-
-
-       . = 0x2100
-
 /*
  * This code finishes saving the registers to the exception frame
  * and jumps to the appropriate handler for the exception.
@@ -1133,28 +1104,12 @@ transfer_to_handler:
        SAVE_4GPRS(8, r21)
        SAVE_8GPRS(12, r21)
        SAVE_8GPRS(24, r21)
-#if 0
-       andi.   r23,r23,MSR_PR
-       mfspr   r23,SPRG3               /* if from user, fix up tss.regs */
-       beq     2f
-       addi    r24,r1,STACK_FRAME_OVERHEAD
-       stw     r24,PT_REGS(r23)
-2:     addi    r2,r23,-TSS             /* set r2 to current */
-       tovirt(r2,r2,r23)
-#endif
        mflr    r23
        andi.   r24,r23,0x3f00          /* get vector offset */
        stw     r24,TRAP(r21)
        li      r22,0
        stw     r22,RESULT(r21)
        mtspr   SPRG2,r22               /* r1 is now kernel sp */
-#if 0
-       addi    r24,r2,TASK_STRUCT_SIZE /* check for kernel stack overflow */
-       cmplw   0,r1,r2
-       cmplw   1,r1,r24
-       crand   1,1,4
-       bgt     stack_ovf               /* if r2 < r1 < r2+TASK_STRUCT_SIZE */
-#endif
        lwz     r24,0(r23)              /* virtual address of handler */
        lwz     r23,4(r23)              /* where to go when done */
        mtspr   SRR0,r24
@@ -1215,16 +1170,64 @@ crit_return:
        REST_GPR(31, r1)
        lwz     r2,_NIP(r1)     /* Restore environment */
        lwz     r0,_MSR(r1)
-       mtspr   990,r2          /* SRR2 */
-       mtspr   991,r0          /* SRR3 */
+        mtspr   csrr0,r2
+        mtspr   csrr1,r0
        lwz     r0,GPR0(r1)
        lwz     r2,GPR2(r1)
        lwz     r1,GPR1(r1)
        SYNC
        rfci
 
-/* Cache functions.
-*/
+#ifdef CONFIG_440
+mck_return:
+        mfmsr   r28             /* Disable interrupts */
+        li      r4,0
+        ori     r4,r4,MSR_EE
+        andc    r28,r28,r4
+        SYNC                    /* Some chip revs need this... */
+        mtmsr   r28
+        SYNC
+        lwz     r2,_CTR(r1)
+        lwz     r0,_LINK(r1)
+        mtctr   r2
+        mtlr    r0
+        lwz     r2,_XER(r1)
+        lwz     r0,_CCR(r1)
+        mtspr   XER,r2
+        mtcrf   0xFF,r0
+        REST_10GPRS(3, r1)
+        REST_10GPRS(13, r1)
+        REST_8GPRS(23, r1)
+        REST_GPR(31, r1)
+        lwz     r2,_NIP(r1)     /* Restore environment */
+        lwz     r0,_MSR(r1)
+        mtspr   mcsrr0,r2
+        mtspr   mcsrr1,r0
+        lwz     r0,GPR0(r1)
+        lwz     r2,GPR2(r1)
+        lwz     r1,GPR1(r1)
+        SYNC
+        rfmci
+#endif /* CONFIG_440 */
+
+
+/*
+ * Cache functions.
+ *
+ * NOTE: currently the 440s run with dcache _disabled_ once relocated to DRAM,
+ * although for some cache-ralated calls stubs have to be provided to satisfy
+ * symbols resolution.
+ *
+ */
+#ifdef CONFIG_440
+       .globl  dcache_disable
+dcache_disable:
+        blr
+
+        .globl  dcache_status
+dcache_status:
+        blr
+#else
 flush_dcache:
        addis   r9,r0,0x0002            /* set mask for EE and CE msr bits */
        ori     r9,r9,0x8000
@@ -1303,24 +1306,13 @@ dcache_status:
        mfdccr  r3
        srwi    r3, r3, 31      /* >>31 => select bit 0 */
        blr
+#endif
 
        .globl get_pvr
 get_pvr:
        mfspr   r3, PVR
        blr
 
-#if !defined(CONFIG_440)
-       .globl wr_pit
-wr_pit:
-       mtspr   pit, r3
-       blr
-#endif
-
-       .globl wr_tcr
-wr_tcr:
-       mtspr   tcr, r3
-       blr
-
 /*------------------------------------------------------------------------------- */
 /* Function:    out16 */
 /* Description:         Output 16 bits */
@@ -1518,7 +1510,7 @@ relocate_code:
  * initialization, now running from RAM.
  */
 
-       addi    r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
+       addi    r0, r10, in_ram - _start + _START_OFFSET
        mtlr    r0
        blr                             /* NEVER RETURNS! */
 
@@ -1588,7 +1580,7 @@ clear_bss:
         */
        .globl  trap_init
 trap_init:
-       lwz     r7, GOT(_start)
+       lwz     r7, GOT(_start_of_vectors)
        lwz     r8, GOT(_end_of_vectors)
 
        li      r9, 0x100               /* reset vector always at 0x100 */
@@ -1608,35 +1600,48 @@ trap_init:
        /*
         * relocate `hdlr' and `int_return' entries
         */
-       li      r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
-       li      r8, Alignment - _start + EXC_OFF_SYS_RESET
+       li      r7, .L_MachineCheck - _start + _START_OFFSET
+       li      r8, Alignment - _start + _START_OFFSET
 2:
        bl      trap_reloc
-       addi    r7, r7, 0x100           /* next exception vector        */
+       addi    r7, r7, 0x100           /* next exception vector */
        cmplw   0, r7, r8
        blt     2b
 
-       li      r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
+       li      r7, .L_Alignment - _start + _START_OFFSET
        bl      trap_reloc
 
-       li      r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
+       li      r7, .L_ProgramCheck - _start + _START_OFFSET
        bl      trap_reloc
 
-       li      r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
-       li      r8, SystemCall - _start + EXC_OFF_SYS_RESET
-3:
-       bl      trap_reloc
-       addi    r7, r7, 0x100           /* next exception vector        */
-       cmplw   0, r7, r8
-       blt     3b
+#ifdef CONFIG_440
+       li      r7, .L_FPUnavailable - _start + _START_OFFSET
+        bl      trap_reloc
 
-       li      r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
-       li      r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
-4:
-       bl      trap_reloc
-       addi    r7, r7, 0x100           /* next exception vector        */
-       cmplw   0, r7, r8
-       blt     4b
+       li      r7, .L_Decrementer - _start + _START_OFFSET
+        bl      trap_reloc
+
+       li      r7, .L_APU - _start + _START_OFFSET
+        bl      trap_reloc
+        
+       li      r7, .L_InstructionTLBError - _start + _START_OFFSET
+        bl      trap_reloc
+
+        li      r7, .L_DataTLBError - _start + _START_OFFSET
+        bl      trap_reloc
+#else /* CONFIG_440 */
+       li      r7, .L_PIT - _start + _START_OFFSET
+        bl      trap_reloc
+
+       li      r7, .L_InstructionTLBMiss - _start + _START_OFFSET
+        bl      trap_reloc
+
+       li      r7, .L_DataTLBMiss - _start + _START_OFFSET
+        bl      trap_reloc
+#endif /* CONFIG_440 */
+
+        li      r7, .L_DebugBreakpoint - _start + _START_OFFSET
+        bl      trap_reloc
 
 #if !defined(CONFIG_440)
        addi    r7,r0,0x1000            /* set ME bit (Machine Exceptions) */