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/*------------------------------------------------------------------------------+ */
/* */
/* 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 */
/*------------------------------------------------------------------------------- */
/*----------------------------------------------------------------------------- */
/* Function: ext_bus_cntlr_init */
/* Description: Initializes the External Bus Controller for the external */
/* peripherals. IMPORTANT: For pass1 this code must run from */
/* cache since you can not reliably change a peripheral banks */
/* timing register (pbxap) while running code from that bank. */
/* For ex., since we are running from ROM on bank 0, we can NOT */
/* execute the code that modifies bank 0 timings from ROM, so */
/* we run it from cache. */
/* */
/*----------------------------------------------------------------------------- */
#include <config.h>
#include <ppc4xx.h>
#define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <asm/cache.h>
#include <asm/mmu.h>
.globl ext_bus_cntlr_init
ext_bus_cntlr_init:
mflr r4 /* save link register */
bl ..getAddr
..getAddr:
mflr r3 /* get address of ..getAddr */
mtlr r4 /* restore link register */
addi r4,0,14 /* set ctr to 10; used to prefetch */
mtctr r4 /* 10 cache lines to fit this function */
/* in cache (gives us 8x10=80 instrctns) */
..ebcloop:
icbt r0,r3 /* prefetch cache line for addr in r3 */
addi r3,r3,32 /* move to next cache line */
bdnz ..ebcloop /* continue for 10 cache lines */
/*------------------------------------------------------------------- */
/* Delay to ensure all accesses to ROM are complete before changing */
/* bank 0 timings. 200usec should be enough. */
/* 200,000,000 (cycles/sec) X .000200 (sec) = 0x9C40 cycles */
/*------------------------------------------------------------------- */
addis r3,0,0x0
ori r3,r3,0xA000 /* ensure 200usec have passed since reset */
mtctr r3
..spinlp:
bdnz ..spinlp /* spin loop */
/*----------------------------------------------------------------------- */
/* Memory Bank 0 (Flash) initialization (from openbios) */
/*----------------------------------------------------------------------- */
addi r4,0,pb0ap
mtdcr ebccfga,r4
addis r4,0,CS0_AP@h
ori r4,r4,CS0_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb0cr
mtdcr ebccfga,r4
addis r4,0,CS0_CR@h
ori r4,r4,CS0_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 1 (NVRAM/RTC) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb1ap
mtdcr ebccfga,r4
addis r4,0,CS1_AP@h
ori r4,r4,CS1_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb1cr
mtdcr ebccfga,r4
addis r4,0,CS1_CR@h
ori r4,r4,CS1_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 2 (A/D converter) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb2ap
mtdcr ebccfga,r4
addis r4,0,CS2_AP@h
ori r4,r4,CS2_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb2cr
mtdcr ebccfga,r4
addis r4,0,CS2_CR@h
ori r4,r4,CS2_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 3 (Ethernet PHY Reset) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb3ap
mtdcr ebccfga,r4
addis r4,0,CS3_AP@h
ori r4,r4,CS3_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb3cr
mtdcr ebccfga,r4
addis r4,0,CS3_CR@h
ori r4,r4,CS3_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 4 (PC-MIP PRSNT1#) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb4ap
mtdcr ebccfga,r4
addis r4,0,CS4_AP@h
ori r4,r4,CS4_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb4cr
mtdcr ebccfga,r4
addis r4,0,CS4_CR@h
ori r4,r4,CS4_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 5 (PC-MIP PRSNT2#) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb5ap
mtdcr ebccfga,r4
addis r4,0,CS5_AP@h
ori r4,r4,CS5_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb5cr
mtdcr ebccfga,r4
addis r4,0,CS5_CR@h
ori r4,r4,CS5_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 6 (CPU LED0) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb6ap
mtdcr ebccfga,r4
addis r4,0,CS6_AP@h
ori r4,r4,CS6_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb6cr
mtdcr ebccfga,r4
addis r4,0,CS6_CR@h
ori r4,r4,CS5_CR@l
mtdcr ebccfgd,r4
/*----------------------------------------------------------------------- */
/* Memory Bank 7 (CPU LED1) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb7ap
mtdcr ebccfga,r4
addis r4,0,CS7_AP@h
ori r4,r4,CS7_AP@l
mtdcr ebccfgd,r4
addi r4,0,pb7cr
mtdcr ebccfga,r4
addis r4,0,CS7_CR@h
ori r4,r4,CS7_CR@l
mtdcr ebccfgd,r4
/* addis r4,r0,FPGA_BRDC@h */
/* ori r4,r4,FPGA_BRDC@l */
/* lbz r3,0(r4) /###*get FPGA board control reg */
/* eieio */
/* ori r3,r3,0x01 /###*set UART1 control to select CTS/RTS */
/* stb r3,0(r4) */
nop /* pass2 DCR errata #8 */
blr
/*----------------------------------------------------------------------------- */
/* Function: sdram_init */
/* Description: Configures SDRAM memory banks on ERIC. */
/* We do manually init our SDRAM. */
/* If we have two SDRAM banks, simply undef SINGLE_BANK (ROLF :-) */
/* It is assumed that a 32MB 12x8(2) SDRAM is used. */
/*----------------------------------------------------------------------------- */
.globl sdram_init
sdram_init:
mflr r31
#ifdef CFG_SDRAM_MANUALLY
/*------------------------------------------------------------------- */
/* Set MB0CF for bank 0. (0-32MB) Address Mode 4 since 12x8(2) */
/*------------------------------------------------------------------- */
addi r4,0,mem_mb0cf
mtdcr memcfga,r4
addis r4,0,MB0CF@h
ori r4,r4,MB0CF@l
mtdcr memcfgd,r4
/*------------------------------------------------------------------- */
/* Set MB1CF for bank 1. (32MB-64MB) Address Mode 4 since 12x8(2) */
/*------------------------------------------------------------------- */
addi r4,0,mem_mb1cf
mtdcr memcfga,r4
addis r4,0,MB1CF@h
ori r4,r4,MB1CF@l
mtdcr memcfgd,r4
/*------------------------------------------------------------------- */
/* Set MB2CF for bank 2. off */
/*------------------------------------------------------------------- */
addi r4,0,mem_mb2cf
mtdcr memcfga,r4
addis r4,0,MB2CF@h
ori r4,r4,MB2CF@l
mtdcr memcfgd,r4
/*------------------------------------------------------------------- */
/* Set MB3CF for bank 3. off */
/*------------------------------------------------------------------- */
addi r4,0,mem_mb3cf
mtdcr memcfga,r4
addis r4,0,MB3CF@h
ori r4,r4,MB3CF@l
mtdcr memcfgd,r4
/*------------------------------------------------------------------- */
/* Set the SDRAM Timing reg, SDTR1 and the refresh timer reg, RTR. */
/* To set the appropriate timings, we need to know the SDRAM speed. */
/* We can use the PLB speed since the SDRAM speed is the same as */
/* the PLB speed. The PLB speed is the FBK divider times the */
/* 405GP reference clock, which on the Walnut board is 33Mhz. */
/* Thus, if FBK div is 2, SDRAM is 66Mhz; if FBK div is 3, SDRAM is */
/* 100Mhz; if FBK is 3, SDRAM is 133Mhz. */
/* NOTE: The Walnut board supports SDRAM speeds of 66Mhz, 100Mhz, and */
/* maybe 133Mhz. */
/*------------------------------------------------------------------- */
mfdcr r5,strap /* determine FBK divider */
/* via STRAP reg to calc PLB speed. */
/* SDRAM speed is the same as the PLB */
/* speed. */
rlwinm r4,r5,4,0x3 /* get FBK divide bits */
..chk_66:
cmpi %cr0,0,r4,0x1
bne ..chk_100
addis r6,0,SDTR_66@h /* SDTR1 value for 66Mhz */
ori r6,r6,SDTR_66@l
addis r7,0,RTR_66 /* RTR value for 66Mhz */
b ..sdram_ok
..chk_100:
cmpi %cr0,0,r4,0x2
bne ..chk_133
addis r6,0,SDTR_100@h /* SDTR1 value for 100Mhz */
ori r6,r6,SDTR_100@l
addis r7,0,RTR_100 /* RTR value for 100Mhz */
b ..sdram_ok
..chk_133:
addis r6,0,0x0107 /* SDTR1 value for 133Mhz */
ori r6,r6,0x4015
addis r7,0,0x07F0 /* RTR value for 133Mhz */
..sdram_ok:
/*------------------------------------------------------------------- */
/* Set SDTR1 */
/*------------------------------------------------------------------- */
addi r4,0,mem_sdtr1
mtdcr memcfga,r4
mtdcr memcfgd,r6
/*------------------------------------------------------------------- */
/* Set RTR */
/*------------------------------------------------------------------- */
addi r4,0,mem_rtr
mtdcr memcfga,r4
mtdcr memcfgd,r7
/*------------------------------------------------------------------- */
/* Delay to ensure 200usec have elapsed since reset. Assume worst */
/* case that the core is running 200Mhz: */
/* 200,000,000 (cycles/sec) X .000200 (sec) = 0x9C40 cycles */
/*------------------------------------------------------------------- */
addis r3,0,0x0000
ori r3,r3,0xA000 /* ensure 200usec have passed since reset */
mtctr r3
..spinlp2:
bdnz ..spinlp2 /* spin loop */
/*------------------------------------------------------------------- */
/* Set memory controller options reg, MCOPT1. */
/* Set DC_EN to '1' and BRD_PRF to '01' for 16 byte PLB Burst */
/* read/prefetch. */
/*------------------------------------------------------------------- */
addi r4,0,mem_mcopt1
mtdcr memcfga,r4
addis r4,0,0x8080 /* set DC_EN=1 */
ori r4,r4,0x0000
mtdcr memcfgd,r4
/*------------------------------------------------------------------- */
/* Delay to ensure 10msec have elapsed since reset. This is */
/* required for the MPC952 to stabalize. Assume worst */
/* case that the core is running 200Mhz: */
/* 200,000,000 (cycles/sec) X .010 (sec) = 0x1E8480 cycles */
/* This delay should occur before accessing SDRAM. */
/*------------------------------------------------------------------- */
addis r3,0,0x001E
ori r3,r3,0x8480 /* ensure 10msec have passed since reset */
mtctr r3
..spinlp3:
bdnz ..spinlp3 /* spin loop */
#else
/*fixme: do SDRAM Autoconfig from EEPROM here */
#endif
mtlr r31 /* restore lr */
blr
|
