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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. */
/* Bank 0 - Flash and SRAM */
/* Bank 1 - NVRAM/RTC */
/* Bank 2 - Keyboard/Mouse controller */
/* Bank 3 - IR controller */
/* Bank 4 - not used */
/* Bank 5 - not used */
/* Bank 6 - not used */
/* Bank 7 - FPGA registers */
/*----------------------------------------------------------------------------- */
#include <ppc4xx.h>
#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 and SRAM) initialization */
/*----------------------------------------------------------------------- */
addi r4,0,pb0ap
mtdcr ebccfga,r4
addis r4,0,0x9B01
ori r4,r4,0x5480
mtdcr ebccfgd,r4
addi r4,0,pb0cr
mtdcr ebccfga,r4
addis r4,0,0xFFF1 /* BAS=0xFFF,BS=0x0(1MB),BU=0x3(R/W), */
ori r4,r4,0x8000 /* BW=0x0( 8 bits) */
mtdcr ebccfgd,r4
blr
/*----------------------------------------------------------------------------- */
/* Function: sdram_init */
/* Description: Dummy implementation here - done in C later */
/*----------------------------------------------------------------------------- */
.globl sdram_init
sdram_init:
blr
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