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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