mirror of
https://github.com/AsahiLinux/u-boot
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317734966e
It was brought to our attention that U-Boot contains code derived from the IBM OpenBIOS source code originally provided with some of the older PowerPC 4xx development boards. As a result, the original license of this code has been carried in the various files for a number of years in the U-Boot project. IBM is dual-licensing the IBM code contributions already present in U-Boot under either the terms of the GNU General Public License version 2, or the original code license already present. Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
140 lines
5.8 KiB
ArmAsm
140 lines
5.8 KiB
ArmAsm
/*------------------------------------------------------------------------------+ */
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/* */
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/* This source code is dual-licensed. You may use it under the terms */
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/* of the GNU General Public License version 2, or under the license */
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/* below. */
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/* */
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/* This source code has been made available to you by IBM on an AS-IS */
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/* basis. Anyone receiving this source is licensed under IBM */
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/* copyrights to use it in any way he or she deems fit, including */
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/* copying it, modifying it, compiling it, and redistributing it either */
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/* with or without modifications. No license under IBM patents or */
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/* patent applications is to be implied by the copyright license. */
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/* */
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/* Any user of this software should understand that IBM cannot provide */
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/* technical support for this software and will not be responsible for */
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/* any consequences resulting from the use of this software. */
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/* */
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/* Any person who transfers this source code or any derivative work */
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/* must include the IBM copyright notice, this paragraph, and the */
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/* preceding two paragraphs in the transferred software. */
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/* */
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/* COPYRIGHT I B M CORPORATION 1995 */
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/* LICENSED MATERIAL - PROGRAM PROPERTY OF I B M */
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/*------------------------------------------------------------------------------- */
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/*----------------------------------------------------------------------------- */
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/* Function: ext_bus_cntlr_init */
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/* Description: Initializes the External Bus Controller for the external */
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/* peripherals. IMPORTANT: For pass1 this code must run from */
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/* cache since you can not reliably change a peripheral banks */
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/* timing register (pbxap) while running code from that bank. */
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/* For ex., since we are running from ROM on bank 0, we can NOT */
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/* execute the code that modifies bank 0 timings from ROM, so */
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/* we run it from cache. */
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/* Bank 0 - Flash and SRAM */
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/* Bank 1 - NVRAM/RTC */
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/* Bank 2 - Keyboard/Mouse controller */
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/* Bank 3 - IR controller */
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/* Bank 4 - not used */
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/* Bank 5 - not used */
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/* Bank 6 - not used */
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/* Bank 7 - FPGA registers */
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/*-----------------------------------------------------------------------------#include <config.h> */
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#include <ppc4xx.h>
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#define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */
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#include <ppc_asm.tmpl>
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#include <ppc_defs.h>
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#include <asm/cache.h>
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#include <asm/mmu.h>
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/* CRAY - L1: only nominally a 'walnut', since ext.Bus.Cntlr is all empty */
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/* except for #1 which we use for DMA'ing to IOCA-like things, so the */
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/* control registers to set that up are determined by what we've */
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/* empirically discovered work there. */
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.globl ext_bus_cntlr_init
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ext_bus_cntlr_init:
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mflr r4 /* save link register */
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bl ..getAddr
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..getAddr:
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mflr r3 /* get address of ..getAddr */
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mtlr r4 /* restore link register */
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addi r4,0,14 /* set ctr to 10; used to prefetch */
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mtctr r4 /* 10 cache lines to fit this function */
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/* in cache (gives us 8x10=80 instrctns) */
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..ebcloop:
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icbt r0,r3 /* prefetch cache line for addr in r3 */
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addi r3,r3,32 /* move to next cache line */
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bdnz ..ebcloop /* continue for 10 cache lines */
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/*------------------------------------------------------------------- */
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/* Delay to ensure all accesses to ROM are complete before changing */
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/* bank 0 timings. 200usec should be enough. */
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/* 200,000,000 (cycles/sec) X .000200 (sec) = 0x9C40 cycles */
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/*------------------------------------------------------------------- */
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addis r3,0,0x0
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ori r3,r3,0xA000 /* ensure 200usec have passed since reset */
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mtctr r3
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..spinlp:
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bdnz ..spinlp /* spin loop */
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/*---------------------------------------------------------------------- */
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/* Peripheral Bank 0 (Flash) initialization */
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/*---------------------------------------------------------------------- */
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/* 0x7F8FFE80 slowest boot */
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addi r4,0,pb0ap
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mtdcr ebccfga,r4
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addis r4,0,0x9B01
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ori r4,r4,0x5480
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mtdcr ebccfgd,r4
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addi r4,0,pb0cr
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mtdcr ebccfga,r4
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addis r4,0,0xFFC5 /* BAS=0xFFC,BS=0x4(4MB),BU=0x3(R/W), */
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ori r4,r4,0x8000 /* BW=0x0( 8 bits) */
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mtdcr ebccfgd,r4
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blr
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/*---------------------------------------------------------------------- */
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/* Peripheral Bank 1 (NVRAM/RTC) initialization */
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/* CRAY:the L1 has NOT this bank, it is tied to SV2/IOCA/etc/ instead */
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/* and we do DMA on it. The ConfigurationRegister part is threfore */
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/* almost arbitrary, except that our linux driver needs to know the */
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/* address, but it can query, it.. */
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/* */
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/* The AccessParameter is CRITICAL, */
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/* thouch, since it needs to agree with the electrical timings on the */
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/* IOCA parallel interface. That value is: 0x0185,4380 */
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/* BurstModeEnable BME=0 */
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/* TransferWait TWT=3 */
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/* ChipSelectOnTiming CSN=1 */
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/* OutputEnableOnTimimg OEN=1 */
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/* WriteByteEnableOnTiming WBN=1 */
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/* WriteByteEnableOffTiming WBF=0 */
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/* TransferHold TH=1 */
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/* ReadyEnable RE=1 */
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/* SampleOnReady SOR=1 */
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/* ByteEnableMode BEM=0 */
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/* ParityEnable PEN=0 */
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/* all reserved bits=0 */
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/*---------------------------------------------------------------------- */
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/*---------------------------------------------------------------------- */
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addi r4,0,pb1ap
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mtdcr ebccfga,r4
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addis r4,0,0x0185 /* hiword */
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ori r4,r4,0x4380 /* loword */
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mtdcr ebccfgd,r4
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addi r4,0,pb1cr
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mtdcr ebccfga,r4
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addis r4,0,0xF001 /* BAS=0xF00,BS=0x0(1MB),BU=0x3(R/W), */
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ori r4,r4,0x8000 /* BW=0x0( 8 bits) */
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mtdcr ebccfgd,r4
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blr
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