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#endif /* CONFIG_COGENT */
/*
* This code initialises the MPC8260 processor core
* (conforms to PowerPC 603e spec)
* Note: expects original MSR contents to be in r5.
*/
.globl init_8260_core
init_8260_core:
/* Initialize machine status; enable machine check interrupt */
/*--------------------------------------------------------------*/
li r3, MSR_KERNEL /* Set ME and RI flags */
rlwimi r3, r5, 0, 25, 25 /* preserve IP bit set by HRCW */
#ifdef DEBUG
rlwimi r3, r5, 0, 21, 22 /* debugger might set SE & BE bits */
#endif
SYNC /* Some chip revs need this... */
mtmsr r3
SYNC
mtspr SRR1, r3 /* Make SRR1 match MSR */
/* Initialise the SYPCR early, and reset the watchdog (if req) */
/*--------------------------------------------------------------*/
lis r3, (CFG_IMMR+IM_REGBASE)@h
#if !defined(CONFIG_COGENT)
lis r4, CFG_SYPCR@h
ori r4, r4, CFG_SYPCR@l
stw r4, IM_SYPCR@l(r3)
#endif /* !CONFIG_COGENT */
#if defined(CONFIG_WATCHDOG)
li r4, 21868 /* = 0x556c */
sth r4, IM_SWSR@l(r3)
li r4, -21959 /* = 0xaa39 */
sth r4, IM_SWSR@l(r3)
#endif /* CONFIG_WATCHDOG */
/* Initialize the Hardware Implementation-dependent Registers */
/* HID0 also contains cache control */
/*--------------------------------------------------------------*/
lis r3, CFG_HID0_INIT@h
ori r3, r3, CFG_HID0_INIT@l
SYNC
mtspr HID0, r3
lis r3, CFG_HID0_FINAL@h
ori r3, r3, CFG_HID0_FINAL@l
SYNC
mtspr HID0, r3
lis r3, CFG_HID2@h
ori r3, r3, CFG_HID2@l
mtspr HID2, r3
/* clear all BAT's */
/*--------------------------------------------------------------*/
li r0, 0
mtspr DBAT0U, r0
mtspr DBAT0L, r0
mtspr DBAT1U, r0
mtspr DBAT1L, r0
mtspr DBAT2U, r0
mtspr DBAT2L, r0
mtspr DBAT3U, r0
mtspr DBAT3L, r0
mtspr IBAT0U, r0
mtspr IBAT0L, r0
mtspr IBAT1U, r0
mtspr IBAT1L, r0
mtspr IBAT2U, r0
mtspr IBAT2L, r0
mtspr IBAT3U, r0
mtspr IBAT3L, r0
SYNC
/* invalidate all tlb's */
/* */
/* From the 603e User Manual: "The 603e provides the ability to */
/* invalidate a TLB entry. The TLB Invalidate Entry (tlbie) */
/* instruction invalidates the TLB entry indexed by the EA, and */
/* operates on both the instruction and data TLBs simultaneously*/
/* invalidating four TLB entries (both sets in each TLB). The */
/* index corresponds to bits 15-19 of the EA. To invalidate all */
/* entries within both TLBs, 32 tlbie instructions should be */
/* issued, incrementing this field by one each time." */
/* */
/* "Note that the tlbia instruction is not implemented on the */
/* 603e." */
/* */
/* bits 15-19 correspond to addresses 0x00000000 to 0x0001F000 */
/* incrementing by 0x1000 each time. The code below is sort of */
/* based on code in "flush_tlbs" from arch/ppc/kernel/head.S */
/* */
/*--------------------------------------------------------------*/
li r3, 32
mtctr r3
li r3, 0
1: tlbie r3
addi r3, r3, 0x1000
bdnz 1b
SYNC
/* Done! */
/*--------------------------------------------------------------*/
blr
#ifdef DEBUG
/*
* initialise things related to debugging.
*
* must be called after the global offset table (GOT) is initialised
* (GET_GOT) and after cpu_init_f() has executed.
*/
.globl init_debug
init_debug:
lis r3, (CFG_IMMR+IM_REGBASE)@h
/* Quick and dirty hack to enable the RAM and copy the */
/* vectors so that we can take exceptions. */
/*--------------------------------------------------------------*/
/* write Memory Refresh Prescaler */
li r4, CFG_MPTPR
sth r4, IM_MPTPR@l(r3)
/* write 60x Refresh Timer */
li r4, CFG_PSRT
stb r4, IM_PSRT@l(r3)
/* init the 60x SDRAM Mode Register */
lis r4, (CFG_PSDMR|PSDMR_OP_NORM)@h
ori r4, r4, (CFG_PSDMR|PSDMR_OP_NORM)@l
stw r4, IM_PSDMR@l(r3)
/* write Precharge All Banks command */
lis r4, (CFG_PSDMR|PSDMR_OP_PREA)@h
ori r4, r4, (CFG_PSDMR|PSDMR_OP_PREA)@l
stw r4, IM_PSDMR@l(r3)
stb r0, 0(0)
/* write eight CBR Refresh commands */
lis r4, (CFG_PSDMR|PSDMR_OP_CBRR)@h
ori r4, r4, (CFG_PSDMR|PSDMR_OP_CBRR)@l
stw r4, IM_PSDMR@l(r3)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
stb r0, 0(0)
/* write Mode Register Write command */
lis r4, (CFG_PSDMR|PSDMR_OP_MRW)@h
ori r4, r4, (CFG_PSDMR|PSDMR_OP_MRW)@l
stw r4, IM_PSDMR@l(r3)
stb r0, 0(0)
/* write Normal Operation command and enable Refresh */
lis r4, (CFG_PSDMR|PSDMR_OP_NORM|PSDMR_RFEN)@h
ori r4, r4, (CFG_PSDMR|PSDMR_OP_NORM|PSDMR_RFEN)@l
stw r4, IM_PSDMR@l(r3)
stb r0, 0(0)
/* RAM should now be operational */
#define VEC_WRD_CNT ((_end_of_vectors - _start + EXC_OFF_SYS_RESET) / 4)
lwz r3, GOT(_end_of_vectors)
rlwinm r4, r3, 0, 18, 31 /* _end_of_vectors & 0x3FFF */
lis r5, VEC_WRD_CNT@h
ori r5, r5, VEC_WRD_CNT@l
mtctr r5
1:
lwzu r5, -4(r3)
stwu r5, -4(r4)
bdnz 1b
/* Load the Instruction Address Breakpoint Register (IABR). */
/* */
/* The address to load is stored in the first word of dual port */
/* ram and should be preserved while the power is on, so you */
/* can plug addresses into that location then reset the cpu and */
/* this code will load that address into the IABR after the */
/* reset. */
/* */
/* When the program counter matches the contents of the IABR, */
/* an exception is generated (before the instruction at that */
/* location completes). The vector for this exception is 0x1300 */
/*--------------------------------------------------------------*/
lis r3, CFG_IMMR@h
lwz r3, 0(r3)
mtspr IABR, r3
/* Set the entire dual port RAM (where the initial stack */
/* resides) to a known value - makes it easier to see where */
/* the stack has been written */
/*--------------------------------------------------------------*/
lis r3, (CFG_IMMR + CFG_INIT_SP_OFFSET)@h
ori r3, r3, (CFG_IMMR + CFG_INIT_SP_OFFSET)@l
li r4, ((CFG_INIT_SP_OFFSET - 4) / 4)
mtctr r4
lis r4, 0xdeadbeaf@h
ori r4, r4, 0xdeadbeaf@l
1:
stwu r4, -4(r3)
bdnz 1b
/* Done! */
/*--------------------------------------------------------------*/
blr
#endif
/* Cache functions.
*
* Note: requires that all cache bits in
* HID0 are in the low half word.
*/
.globl icache_enable
icache_enable:
mfspr r3, HID0
ori r3, r3, HID0_ICE
lis r4, 0
ori r4, r4, HID0_ILOCK
andc r3, r3, r4
ori r4, r3, HID0_ICFI
isync
mtspr HID0, r4 /* sets enable and invalidate, clears lock */
isync
mtspr HID0, r3 /* clears invalidate */
blr
.globl icache_disable
icache_disable:
mfspr r3, HID0
lis r4, 0
ori r4, r4, HID0_ICE|HID0_ILOCK
andc r3, r3, r4
ori r4, r3, HID0_ICFI
isync
mtspr HID0, r4 /* sets invalidate, clears enable and lock */
isync
mtspr HID0, r3 /* clears invalidate */
blr
.globl icache_status
icache_status:
mfspr r3, HID0
rlwinm r3, r3, HID0_ICE_BITPOS + 1, 31, 31
blr
.globl dcache_enable
dcache_enable:
mfspr r3, HID0
ori r3, r3, HID0_DCE
lis r4, 0
ori r4, r4, HID0_DLOCK
andc r3, r3, r4
ori r4, r3, HID0_DCI
sync
mtspr HID0, r4 /* sets enable and invalidate, clears lock */
sync
mtspr HID0, r3 /* clears invalidate */
blr
.globl dcache_disable
dcache_disable:
mfspr r3, HID0
lis r4, 0
ori r4, r4, HID0_DCE|HID0_DLOCK
andc r3, r3, r4
ori r4, r3, HID0_DCI
sync
mtspr HID0, r4 /* sets invalidate, clears enable and lock */
sync
mtspr HID0, r3 /* clears invalidate */
blr
.globl dcache_status
dcache_status:
mfspr r3, HID0
rlwinm r3, r3, HID0_DCE_BITPOS + 1, 31, 31
blr
.globl get_pvr
get_pvr:
mfspr r3, PVR
blr
/*------------------------------------------------------------------------------*/
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
* r3 = dest
* r4 = src
* r5 = length in bytes
* r6 = cachelinesize
*/
.globl relocate_code
relocate_code:
mr r1, r3 /* Set new stack pointer */
mr r9, r4 /* Save copy of Global Data pointer */
mr r10, r5 /* Save copy of Destination Address */
mr r3, r5 /* Destination Address */
lis r4, CFG_MONITOR_BASE@h /* Source Address */
ori r4, r4, CFG_MONITOR_BASE@l
lwz r5, GOT(__init_end)
sub r5, r5, r4
li r6, CFG_CACHELINE_SIZE /* Cache Line Size */
/*
* Fix GOT pointer:
*
* New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
*
* Offset:
*/
sub r15, r10, r4
/* First our own GOT */
add r14, r14, r15
/* then the one used by the C code */
add r30, r30, r15
/*
* Now relocate code
*/
cmplw cr1,r3,r4
addi r0,r5,3
srwi. r0,r0,2
beq cr1,4f /* In place copy is not necessary */
beq 7f /* Protect against 0 count */
mtctr r0
bge cr1,2f
la r8,-4(r4)
la r7,-4(r3)
1: lwzu r0,4(r8)
stwu r0,4(r7)
bdnz 1b
b 4f
2: slwi r0,r0,2
add r8,r4,r0
add r7,r3,r0
3: lwzu r0,-4(r8)
stwu r0,-4(r7)
bdnz 3b
/*
* Now flush the cache: note that we must start from a cache aligned
* address. Otherwise we might miss one cache line.
*/
4: cmpwi r6,0
add r5,r3,r5
beq 7f /* Always flush prefetch queue in any case */
subi r0,r6,1
andc r3,r3,r0
mfspr r7,HID0 /* don't do dcbst if dcache is disabled */
rlwinm r7,r7,HID0_DCE_BITPOS+1,31,31
cmpwi r7,0
beq 9f
mr r4,r3
5: dcbst 0,r4
add r4,r4,r6
cmplw r4,r5
blt 5b
sync /* Wait for all dcbst to complete on bus */
9: mfspr r7,HID0 /* don't do icbi if icache is disabled */
rlwinm r7,r7,HID0_ICE_BITPOS+1,31,31
cmpwi r7,0
beq 7f
mr r4,r3
6: icbi 0,r4
add r4,r4,r6
cmplw r4,r5
blt 6b
7: sync /* Wait for all icbi to complete on bus */
isync
/*
* We are done. Do not return, instead branch to second part of board
* initialization, now running from RAM.
*/
addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
mtlr r0
blr
in_ram:
/*
* Relocation Function, r14 point to got2+0x8000
*
* Adjust got2 pointers, no need to check for 0, this code
* already puts a few entries in the table.
*/
li r0,__got2_entries@sectoff@l
la r3,GOT(_GOT2_TABLE_)
lwz r11,GOT(_GOT2_TABLE_)
mtctr r0
sub r11,r3,r11
addi r3,r3,-4
1: lwzu r0,4(r3)
add r0,r0,r11
stw r0,0(r3)
bdnz 1b
/*
* Now adjust the fixups and the pointers to the fixups
* in case we need to move ourselves again.
*/
2: li r0,__fixup_entries@sectoff@l
lwz r3,GOT(_FIXUP_TABLE_)
cmpwi r0,0
mtctr r0
addi r3,r3,-4
beq 4f
3: lwzu r4,4(r3)
lwzux r0,r4,r11
add r0,r0,r11
stw r10,0(r3)
stw r0,0(r4)
bdnz 3b
4:
clear_bss:
/*
* Now clear BSS segment
*/
lwz r3,GOT(__bss_start)
#if defined(CONFIG_HYMOD)
/*
* For HYMOD - the environment is the very last item in flash.
* The real .bss stops just before environment starts, so only
* clear up to that point.
*
* taken from mods for FADS board
*/
lwz r4,GOT(environment)
#else
lwz r4,GOT(_end)
#endif
cmplw 0, r3, r4
beq 6f
li r0, 0
5:
stw r0, 0(r3)
addi r3, r3, 4
cmplw 0, r3, r4
bne 5b
6:
mr r3, r9 /* Global Data pointer */
mr r4, r10 /* Destination Address */
bl board_init_r
/*
* Copy exception vector code to low memory
*
* r3: dest_addr
* r7: source address, r8: end address, r9: target address
*/
.globl trap_init
trap_init:
lwz r7, GOT(_start)
lwz r8, GOT(_end_of_vectors)
li r9, 0x100 /* reset vector always at 0x100 */
cmplw 0, r7, r8
bgelr /* return if r7>=r8 - just in case */
mflr r4 /* save link register */
1:
lwz r0, 0(r7)
stw r0, 0(r9)
addi r7, r7, 4
addi r9, r9, 4
cmplw 0, r7, r8
bne 1b
/*
* relocate `hdlr' and `int_return' entries
*/
li r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
li r8, Alignment - _start + EXC_OFF_SYS_RESET
2:
bl trap_reloc
addi r7, r7, 0x100 /* next exception vector */
cmplw 0, r7, r8
blt 2b
li r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
bl trap_reloc
li r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
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
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
mfmsr r3 /* now that the vectors have */
lis r7, MSR_IP@h /* relocated into low memory */
ori r7, r7, MSR_IP@l /* MSR[IP] can be turned off */
andc r3, r3, r7 /* (if it was on) */
SYNC /* Some chip revs need this... */
mtmsr r3
SYNC
mtlr r4 /* restore link register */
blr
/*
* Function: relocate entries for one exception vector
*/
trap_reloc:
lwz r0, 0(r7) /* hdlr ... */
add r0, r0, r3 /* ... += dest_addr */
stw r0, 0(r7)
lwz r0, 4(r7) /* int_return ... */
add r0, r0, r3 /* ... += dest_addr */
stw r0, 4(r7)
blr
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