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Diffstat (limited to 'src/cpu/ppc/ppc4xx/ppc4xx.inc')
| -rw-r--r-- | src/cpu/ppc/ppc4xx/ppc4xx.inc | 750 |
1 files changed, 750 insertions, 0 deletions
diff --git a/src/cpu/ppc/ppc4xx/ppc4xx.inc b/src/cpu/ppc/ppc4xx/ppc4xx.inc new file mode 100644 index 0000000000..b365988d6c --- /dev/null +++ b/src/cpu/ppc/ppc4xx/ppc4xx.inc @@ -0,0 +1,750 @@ +#if 0 +/* + * Copyright (C) 1998 Dan Malek <dmalek@jlc.net> + * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se> + * Copyright (C) 2000,2001,2002 Wolfgang Denk <wd@denx.de> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + * This source code has been made available to you by IBM on an AS-IS + * basis. Anyone receiving this source is licensed under IBM + * copyrights to use it in any way he or she deems fit, including + * copying it, modifying it, compiling it, and redistributing it either + * with or without modifications. No license under IBM patents or + * patent applications is to be implied by the copyright license. + * + * Any user of this software should understand that IBM cannot provide + * technical support for this software and will not be responsible for + * any consequences resulting from the use of this software. + * + * Any person who transfers this source code or any derivative work + * must include the IBM copyright notice, this paragraph, and the + * preceding two paragraphs in the transferred software. + * + * COPYRIGHT I B M CORPORATION 1995 + * LICENSED MATERIAL - PROGRAM PROPERTY OF I B M + * + */ + +/* + * Startup Code for IBM 4xx PowerPC based Embedded Boards + * + * Base on the U-Boot Startup Code + * + * The processor starts at 0xfffffffc and the code is executed + * from flash/rom. + * in memory, but as long we don't jump around before relocating. + * board_init lies at a quite high address and when the cpu has + * jumped there, everything is ok. + * This works because the cpu gives the FLASH (CS0) the whole + * address space at startup, and board_init lies as a echo of + * the flash somewhere up there in the memorymap. + * + * board_init will change CS0 to be positioned at the correct + * address and (s)dram will be positioned at address 0 + */ +#include <ppc_asm.tmpl> +#include <ppc_defs.h> + + .globl _start +_start: + +/*****************************************************************************/ + addi r4,r0,0x0000 + mtspr sgr,r4 + mtspr dcwr,r4 + mtesr r4 /* clear Exception Syndrome Reg */ + mttcr r4 /* clear Timer Control Reg */ + mtxer r4 /* clear Fixed-Point Exception Reg */ + mtevpr r4 /* clear Exception Vector Prefix Reg */ + addi r4,r0,0x1000 /* set ME bit (Machine Exceptions) */ + oris r4,r4,0x0002 /* set CE bit (Critical Exceptions) */ + mtmsr r4 /* change MSR */ + addi r4,r0,(0xFFFF-0x10000) /* set r4 to 0xFFFFFFFF (status in the */ + /* dbsr is cleared by setting bits to 1) */ + mtdbsr r4 /* clear/reset the dbsr */ + + /*----------------------------------------------------------------------- */ + /* Invalidate I and D caches. Enable I cache for defined memory regions */ + /* to speed things up. Leave the D cache disabled for now. It will be */ + /* enabled/left disabled later based on user selected menu options. */ + /* Be aware that the I cache may be disabled later based on the menu */ + /* options as well. See miscLib/main.c. */ + /*----------------------------------------------------------------------- */ + bl invalidate_icache + bl invalidate_dcache + + /*----------------------------------------------------------------------- */ + /* Enable two 128MB cachable regions. */ + /*----------------------------------------------------------------------- */ + addis r4,r0,0x8000 + addi r4,r4,0x0001 + mticcr r4 /* instruction cache */ + isync + + addis r4,r0,0x0000 + addi r4,r4,0x0000 + mtdccr r4 /* data cache */ + +#if !(defined(CFG_EBC_PB0AP) && defined(CFG_EBC_PB0CR)) + /*----------------------------------------------------------------------- */ + /* Tune the speed and size for flash CS0 */ + /*----------------------------------------------------------------------- */ + bl ext_bus_cntlr_init +#endif + +#if defined(CONFIG_405EP) + /*----------------------------------------------------------------------- */ + /* DMA Status, clear to come up clean */ + /*----------------------------------------------------------------------- */ + addis r3,r0, 0xFFFF /* Clear all existing DMA status */ + ori r3,r3, 0xFFFF + mtdcr dmasr, r3 + + bl ppc405ep_init /* do ppc405ep specific init */ +#endif /* CONFIG_405EP */ + + /*----------------------------------------------------------------------- */ + /* Setup temporary stack in DCACHE or OCM if needed for SDRAM SPD. */ + /*----------------------------------------------------------------------- */ +#ifdef CFG_INIT_DCACHE_CS + /*----------------------------------------------------------------------- */ + /* Memory Bank x (nothingness) initialization 1GB+64MEG */ + /* used as temporary stack pointer for stage0 */ + /*----------------------------------------------------------------------- */ + li r4,PBxAP + mtdcr ebccfga,r4 + lis r4,0x0380 + ori r4,r4,0x0480 + mtdcr ebccfgd,r4 + + addi r4,0,PBxCR + mtdcr ebccfga,r4 + lis r4,0x400D + ori r4,r4,0xa000 + mtdcr ebccfgd,r4 + + /* turn on data chache for this region */ + lis r4,0x0080 + mtdccr r4 + + /* set stack pointer and clear stack to known value */ + + lis r1,CFG_INIT_RAM_ADDR@h + ori r1,r1,CFG_INIT_SP_OFFSET@l + + li r4,2048 /* we store 2048 words to stack */ + mtctr r4 + + lis r2,CFG_INIT_RAM_ADDR@h /* we also clear data area */ + ori r2,r2,CFG_INIT_RAM_END@l /* so cant copy value from r1 */ + + lis r4,0xdead /* we store 0xdeaddead in the stack */ + ori r4,r4,0xdead + +..stackloop: + stwu r4,-4(r2) + bdnz ..stackloop + + li r0, 0 /* Make room for stack frame header and */ + stwu r0, -4(r1) /* clear final stack frame so that */ + stwu r0, -4(r1) /* stack backtraces terminate cleanly */ + /* + * Set up a dummy frame to store reset vector as return address. + * this causes stack underflow to reset board. + */ + stwu r1, -8(r1) /* Save back chain and move SP */ + addis r0, 0, RESET_VECTOR@h /* Address of reset vector */ + ori r0, r0, RESET_VECTOR@l + stwu r1, -8(r1) /* Save back chain and move SP */ + stw r0, +12(r1) /* Save return addr (underflow vect) */ +#endif /* CFG_INIT_DCACHE_CS */ + + /*----------------------------------------------------------------------- */ + /* Initialize SDRAM Controller */ + /*----------------------------------------------------------------------- */ + bl sdram_init + + /* + * Setup temporary stack pointer only for boards + * that do not use SDRAM SPD I2C stuff since it + * is already initialized to use DCACHE or OCM + * stacks. + */ +#if !(defined(CFG_INIT_DCACHE_CS) || defined(CFG_TEMP_STACK_OCM)) + lis r1, CFG_INIT_RAM_ADDR@h + ori r1,r1,CFG_INIT_SP_OFFSET /* set up the stack in SDRAM */ + + li r0, 0 /* Make room for stack frame header and */ + stwu r0, -4(r1) /* clear final stack frame so that */ + stwu r0, -4(r1) /* stack backtraces terminate cleanly */ + /* + * Set up a dummy frame to store reset vector as return address. + * this causes stack underflow to reset board. + */ + stwu r1, -8(r1) /* Save back chain and move SP */ + lis r0, RESET_VECTOR@h /* Address of reset vector */ + ori r0, r0, RESET_VECTOR@l + stwu r1, -8(r1) /* Save back chain and move SP */ + stw r0, +12(r1) /* Save return addr (underflow vect) */ +#endif /* !(CFG_INIT_DCACHE_CS || !CFG_TEM_STACK_OCM) */ + + GET_GOT /* initialize GOT access */ + + bl cpu_init_f /* run low-level CPU init code (from Flash) */ + + /* NEVER RETURNS! */ + bl board_init_f /* run first part of init code (from Flash) */ + + + +/* Cache functions. +*/ +invalidate_icache: + iccci r0,r0 /* for 405, iccci invalidates the */ + blr /* entire I cache */ + +invalidate_dcache: + addi r6,0,0x0000 /* clear GPR 6 */ + /* Do loop for # of dcache congruence classes. */ + addi r7,r0, (CFG_DCACHE_SIZE / CFG_CACHELINE_SIZE / 2) + /* NOTE: dccci invalidates both */ + mtctr r7 /* ways in the D cache */ +..dcloop: + dccci 0,r6 /* invalidate line */ + addi r6,r6, CFG_CACHELINE_SIZE /* bump to next line */ + bdnz ..dcloop + blr + +flush_dcache: + addis r9,r0,0x0002 /* set mask for EE and CE msr bits */ + ori r9,r9,0x8000 + mfmsr r12 /* save msr */ + andc r9,r12,r9 + mtmsr r9 /* disable EE and CE */ + addi r10,r0,0x0001 /* enable data cache for unused memory */ + mfdccr r9 /* region 0xF8000000-0xFFFFFFFF via */ + or r10,r10,r9 /* bit 31 in dccr */ + mtdccr r10 + + /* do loop for # of congruence classes. */ + addi r10,r0,(CFG_DCACHE_SIZE / CFG_CACHELINE_SIZE / 2) + addi r11,r0,(CFG_DCACHE_SIZE / 2) /* D cache set size - 2 way sets */ + mtctr r10 + addi r10,r0,(0xE000-0x10000) /* start at 0xFFFFE000 */ + add r11,r10,r11 /* add to get to other side of cache line */ +..flush_dcache_loop: + lwz r3,0(r10) /* least recently used side */ + lwz r3,0(r11) /* the other side */ + dccci r0,r11 /* invalidate both sides */ + addi r10,r10,CFG_CACHELINE_SIZE /* bump to next line */ + addi r11,r11,CFG_CACHELINE_SIZE /* bump to next line */ + bdnz ..flush_dcache_loop + sync /* allow memory access to complete */ + mtdccr r9 /* restore dccr */ + mtmsr r12 /* restore msr */ + blr + + .globl icache_enable +icache_enable: + mflr r8 + bl invalidate_icache + mtlr r8 + isync + addis r3,r0, 0x8000 /* set bit 0 */ + mticcr r3 + blr + + .globl icache_disable +icache_disable: + addis r3,r0, 0x0000 /* clear bit 0 */ + mticcr r3 + isync + blr + + .globl icache_status +icache_status: + mficcr r3 + srwi r3, r3, 31 /* >>31 => select bit 0 */ + blr + + .globl dcache_enable +dcache_enable: + mflr r8 + bl invalidate_dcache + mtlr r8 + isync + addis r3,r0, 0x8000 /* set bit 0 */ + mtdccr r3 + blr + + .globl dcache_disable +dcache_disable: + mflr r8 + bl flush_dcache + mtlr r8 + addis r3,r0, 0x0000 /* clear bit 0 */ + mtdccr r3 + blr + + .globl dcache_status +dcache_status: + mfdccr r3 + srwi r3, r3, 31 /* >>31 => select bit 0 */ + blr + + .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: ppcDcbf */ +/* Description: Data Cache block flush */ +/* Input: r3 = effective address */ +/* Output: none. */ +/*------------------------------------------------------------------------------- */ + .globl ppcDcbf +ppcDcbf: + dcbf r0,r3 + blr + +/*------------------------------------------------------------------------------- */ +/* Function: ppcDcbi */ +/* Description: Data Cache block Invalidate */ +/* Input: r3 = effective address */ +/* Output: none. */ +/*------------------------------------------------------------------------------- */ + .globl ppcDcbi +ppcDcbi: + dcbi r0,r3 + blr + +/*------------------------------------------------------------------------------- */ +/* Function: ppcSync */ +/* Description: Processor Synchronize */ +/* Input: none. */ +/* Output: none. */ +/*------------------------------------------------------------------------------- */ + .globl ppcSync +ppcSync: + sync + 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 Init 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 + /* the 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 + 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 */ + 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 /* NEVER RETURNS! */ + +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) + lwz r4,GOT(_end) + + 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 /* Init 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 + + 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 + + +#ifdef CONFIG_405EP +ppc405ep_init: + /* + !----------------------------------------------------------------------- + ! Check FPGA for PCI internal/external arbitration + ! If board is set to internal arbitration, update cpc0_pci + !----------------------------------------------------------------------- + */ + addi r3,0,CPC0_PCI_HOST_CFG_EN +#ifdef CONFIG_BUBINGA405EP + addis r5,r0,FPGA_REG1@h /* set offset for FPGA_REG1 */ + ori r5,r5,FPGA_REG1@l + lbz r5,0x0(r5) /* read to get PCI arb selection */ + andi. r6,r5,FPGA_REG1_PCI_INT_ARB /* using internal arbiter ?*/ + beq ..pci_cfg_set /* if not set, then bypass reg write*/ +#endif + ori r3,r3,CPC0_PCI_ARBIT_EN +..pci_cfg_set: + mtdcr CPC0_PCI, r3 /* Enable internal arbiter*/ + + /* + !----------------------------------------------------------------------- + ! Check to see if chip is in bypass mode. + ! If so, write stored CPC0_PLLMR0 and CPC0_PLLMR1 values and perform a + ! CPU reset Otherwise, skip this step and keep going. + ! Note: Running BIOS in bypass mode is not supported since PLB speed + ! will not be fast enough for the SDRAM (min 66MHz) + !----------------------------------------------------------------------- + */ + mfdcr r5, CPC0_PLLMR1 + rlwinm r4,r5,1,0x1 /* get system clock source (SSCS) */ + cmpi cr0,0,r4,0x1 + + beq pll_done /* if SSCS =b'1' then PLL has */ + /* already been set */ + /* and CPU has been reset */ + /* so skip to next section */ + +#ifdef CONFIG_BUBINGA405EP + /* + !----------------------------------------------------------------------- + ! Read NVRAM to get value to write in PLLMR. + ! If value has not been correctly saved, write default value + ! Default config values (assuming on-board 33MHz SYS_CLK) are above. + ! See CPU_DEFAULT_200 and CPU_DEFAULT_266 above. + ! + ! WARNING: This code assumes the first three words in the nvram_t + ! structure in openbios.h. Changing the beginning of + ! the structure will break this code. + ! + !----------------------------------------------------------------------- + */ + addis r3,0,NVRAM_BASE@h + addi r3,r3,NVRAM_BASE@l + + lwz r4, 0(r3) + addis r5,0,NVRVFY1@h + addi r5,r5,NVRVFY1@l + cmp cr0,0,r4,r5 /* Compare 1st NVRAM Magic number*/ + bne ..no_pllset + addi r3,r3,4 + lwz r4, 0(r3) + addis r5,0,NVRVFY2@h + addi r5,r5,NVRVFY2@l + cmp cr0,0,r4,r5 /* Compare 2 NVRAM Magic number */ + bne ..no_pllset + addi r3,r3,8 /* Skip over conf_size */ + lwz r4, 4(r3) /* Load PLLMR1 value from NVRAM */ + lwz r3, 0(r3) /* Load PLLMR0 value from NVRAM */ + rlwinm r5,r4,1,0x1 /* get system clock source (SSCS) */ + cmpi cr0,0,r5,1 /* See if PLL is locked */ + beq pll_write +..no_pllset: +#endif /* CONFIG_BUBINGA405EP */ + + addis r3,0,PLLMR0_DEFAULT@h /* PLLMR0 default value */ + ori r3,r3,PLLMR0_DEFAULT@l /* */ + addis r4,0,PLLMR1_DEFAULT@h /* PLLMR1 default value */ + ori r4,r4,PLLMR1_DEFAULT@l /* */ + + b pll_write /* Write the CPC0_PLLMR with new value */ + +pll_done: + /* + !----------------------------------------------------------------------- + ! Clear Soft Reset Register + ! This is needed to enable PCI if not booting from serial EPROM + !----------------------------------------------------------------------- + */ + addi r3, 0, 0x0 + mtdcr CPC0_SRR, r3 + + addis r3,0,0x0010 + mtctr r3 +pci_wait: + bdnz pci_wait + + blr /* return to main code */ + +/* +!----------------------------------------------------------------------------- +! Function: pll_write +! Description: Updates the value of the CPC0_PLLMR according to CMOS27E documentation +! That is: +! 1. Pll is first disabled (de-activated by putting in bypass mode) +! 2. PLL is reset +! 3. Clock dividers are set while PLL is held in reset and bypassed +! 4. PLL Reset is cleared +! 5. Wait 100us for PLL to lock +! 6. A core reset is performed +! Input: r3 = Value to write to CPC0_PLLMR0 +! Input: r4 = Value to write to CPC0_PLLMR1 +! Output r3 = none +!----------------------------------------------------------------------------- +*/ +pll_write: + mfdcr r5, CPC0_UCR + andis. r5,r5,0xFFFF + ori r5,r5,0x0101 /* Stop the UART clocks */ + mtdcr CPC0_UCR,r5 /* Before changing PLL */ + + mfdcr r5, CPC0_PLLMR1 + rlwinm r5,r5,0,0x7FFFFFFF /* Disable PLL */ + mtdcr CPC0_PLLMR1,r5 + oris r5,r5,0x4000 /* Set PLL Reset */ + mtdcr CPC0_PLLMR1,r5 + + mtdcr CPC0_PLLMR0,r3 /* Set clock dividers */ + rlwinm r5,r4,0,0x3FFFFFFF /* Reset & Bypass new PLL dividers */ + oris r5,r5,0x4000 /* Set PLL Reset */ + mtdcr CPC0_PLLMR1,r5 /* Set clock dividers */ + rlwinm r5,r5,0,0xBFFFFFFF /* Clear PLL Reset */ + mtdcr CPC0_PLLMR1,r5 + + /* + ! Wait min of 100us for PLL to lock. + ! See CMOS 27E databook for more info. + ! At 200MHz, that means waiting 20,000 instructions + */ + addi r3,0,20000 /* 2000 = 0x4e20 */ + mtctr r3 +pll_wait: + bdnz pll_wait + + oris r5,r5,0x8000 /* Enable PLL */ + mtdcr CPC0_PLLMR1,r5 /* Engage */ + + /* + * Reset CPU to guarantee timings are OK + * Not sure if this is needed... + */ + addis r3,0,0x1000 + mtspr dbcr0,r3 /* This will cause a CPU core reset, and */ + /* execution will continue from the poweron */ + /* vector of 0xfffffffc */ +#endif /* CONFIG_405EP */ +#endif |