Commit efa35cf1 authored by Grzegorz Bernacki's avatar Grzegorz Bernacki Committed by Stefan Roese
Browse files

ppc4xx: Clean up 440 exceptions handling



- Introduced dedicated switches for building 440 and 405 images required
  for 440-specific machine instructions like 'rfmci' etc.

- Exception vectors moved to the proper location (_start moved away from
  the critical exception handler space, which it occupied)

- CriticalInput now serviced (with default handler)

- MachineCheck properly serviced (added a dedicated handler and return
  subroutine)

- Overall cleanup of exceptions declared with STD_EXCEPTION macro (unused,
  unhandled and those not relevant for 4xx were eliminated)

- Eliminated Linux leftovers, removed dead code
Signed-off-by: default avatarGrzegorz Bernacki <gjb@semihalf.com>
Signed-off-by: default avatarRafal Jaworowski <raj@semihalf.com>
Signed-off-by: default avatarStefan Roese <sr@denx.de>
parent 725671cc
......@@ -22,5 +22,13 @@
#
PLATFORM_RELFLAGS += -fPIC -ffixed-r14 -meabi -fno-strict-aliasing
PLATFORM_CPPFLAGS += -DCONFIG_4xx -ffixed-r2 -ffixed-r29 -mstring -msoft-float
PLATFORM_CPPFLAGS += -DCONFIG_4xx -ffixed-r2 -ffixed-r29 -mstring -Wa,-m405 -mcpu=405 -msoft-float
cfg=$(shell grep configs $(TOPDIR)/include/config.h | sed 's/.*<\(configs.*\)>/\1/')
is440=$(shell grep CONFIG_440 $(TOPDIR)/include/$(cfg))
ifneq (,$(findstring CONFIG_440,$(is440)))
PLATFORM_CPPFLAGS += -Wa,-m440 -mcpu=440
else
PLATFORM_CPPFLAGS += -Wa,-m405 -mcpu=405
endif
......@@ -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) */
......
......@@ -36,6 +36,8 @@
#include <command.h>
#include <asm/processor.h>
DECLARE_GLOBAL_DATA_PTR;
#if (CONFIG_COMMANDS & CFG_CMD_KGDB)
int (*debugger_exception_handler)(struct pt_regs *) = 0;
#endif
......@@ -45,8 +47,7 @@ extern unsigned long search_exception_table(unsigned long);
/* THIS NEEDS CHANGING to use the board info structure.
*/
#define END_OF_MEM 0x00400000
#define END_OF_MEM (gd->bd->bi_memstart + gd->bd->bi_memsize)
static __inline__ void set_tsr(unsigned long val)
{
......@@ -88,29 +89,29 @@ extern void do_bedbug_breakpoint(struct pt_regs *);
void
print_backtrace(unsigned long *sp)
{
int cnt = 0;
unsigned long i;
printf("Call backtrace: ");
while (sp) {
if ((uint)sp > END_OF_MEM)
break;
i = sp[1];
if (cnt++ % 7 == 0)
printf("\n");
printf("%08lX ", i);
if (cnt > 32) break;
sp = (unsigned long *)*sp;
}
printf("\n");
int cnt = 0;
unsigned long i;
printf("Call backtrace: ");
while (sp) {
if ((uint)sp > END_OF_MEM)
break;
i = sp[1];
if (cnt++ % 7 == 0)
printf("\n");
printf("%08lX ", i);
if (cnt > 32) break;
sp = (unsigned long *)*sp;
}
printf("\n");
}
void show_regs(struct pt_regs * regs)
{
int i;
printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DAR: %08lX\n",
printf("NIP: %08lX XER: %08lX LR: %08lX REGS: %p TRAP: %04lx DEAR: %08lX\n",
regs->nip, regs->xer, regs->link, regs, regs->trap, regs->dar);
printf("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
......@@ -139,14 +140,14 @@ _exception(int signr, struct pt_regs *regs)
{
show_regs(regs);
print_backtrace((unsigned long *)regs->gpr[1]);
panic("Exception in kernel pc %lx signal %d",regs->nip,signr);
panic("Exception");
}
void
MachineCheckException(struct pt_regs *regs)
{
unsigned long fixup;
unsigned long fixup, val;
/* Probing PCI using config cycles cause this exception
* when a device is not present. Catch it and return to
* the PCI exception handler.
......@@ -161,26 +162,50 @@ MachineCheckException(struct pt_regs *regs)
return;
#endif
printf("Machine check in kernel mode.\n");
printf("Machine Check Exception.\n");
printf("Caused by (from msr): ");
printf("regs %p ",regs);
switch( regs->msr & 0x000F0000) {
case (0x80000000>>12):
printf("Machine check signal - probably due to mm fault\n"
"with mmu off\n");
break;
case (0x80000000>>13):
printf("Transfer error ack signal\n");
break;
case (0x80000000>>14):
printf("Data parity signal\n");
break;
case (0x80000000>>15):
printf("Address parity signal\n");
break;
default:
printf("Unknown values in msr\n");
printf("regs %p ", regs);
val = get_esr();
#if !defined(CONFIG_440)
if (val& ESR_IMCP) {
printf("Instruction");
mtspr(ESR, val & ~ESR_IMCP);
} else
printf("Data");
printf(" machine check.\n");
#elif defined(CONFIG_440)
if (val& ESR_IMCP){
printf("Instruction Synchronous Machine Check exception\n");
mtspr(SPRN_ESR, val & ~ESR_IMCP);
}
else {
val = mfspr(MCSR);
if (val & MCSR_IB)
printf("Instruction Read PLB Error\n");
if (val & MCSR_DRB)
printf("Data Read PLB Error\n");
if (val & MCSR_DWB)
printf("Data Write PLB Error\n");
if (val & MCSR_TLBP)
printf("TLB Parity Error\n");
if (val & MCSR_ICP){
/*flush_instruction_cache(); */
printf("I-Cache Parity Error\n");
}
if (val & MCSR_DCSP)
printf("D-Cache Search Parity Error\n");
if (val & MCSR_DCFP)
printf("D-Cache Flush Parity Error\n");
if (val & MCSR_IMPE)
printf("Machine Check exception is imprecise\n");
/* Clear MCSR */
mtspr(SPRN_MCSR, val);
}
#endif
show_regs(regs);
print_backtrace((unsigned long *)regs->gpr[1]);
panic("machine check");
......@@ -224,7 +249,7 @@ ProgramCheckException(struct pt_regs *regs)
}
void
PITException(struct pt_regs *regs)
DecrementerPITException(struct pt_regs *regs)
{
/*
* Reset PIT interrupt
......
......@@ -308,7 +308,7 @@
#define SPRN_SRR0 0x01A /* Save/Restore Register 0 */
#define SPRN_SRR1 0x01B /* Save/Restore Register 1 */
#define SPRN_SRR2 0x3DE /* Save/Restore Register 2 */
#define SPRN_SRR3 0x3DF /* Save/Restore Register 3 */
#define SPRN_SRR3 0x3DF /* Save/Restore Register 3 */
#ifdef CONFIG_BOOKE
#define SPRN_SVR 0x3FF /* System Version Register */
#else
......@@ -451,6 +451,17 @@
#define SPRN_PID1 0x279 /* Process ID Register 1 */
#define SPRN_PID2 0x27a /* Process ID Register 2 */
#define SPRN_MCSR 0x23c /* Machine Check Syndrome register */
#ifdef CONFIG_440
#define MCSR_MCS 0x80000000 /* Machine Check Summary */
#define MCSR_IB 0x40000000 /* Instruction PLB Error */
#define MCSR_DRB 0x20000000 /* Data Read PLB Error */
#define MCSR_DWB 0x10000000 /* Data Write PLB Error */