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![Stefan Roese](/assets/img/avatar_default.png)
Historically the 405 U-Boot port had a dram_init() call in early init stage. This function was still called from start.S and most of the time coded in assembler. This is not needed anymore (since a long time) and boards should implement the common initdram() function in C instead. This patch now removed the dram_init() call from start.S and removes the empty implementations that are scattered through most of the 405 board ports. Some older board ports really implement this dram_init() though. These are: csb272 csb472 ERIC EXBITGEN W7OLMC W7OLMG I changed those boards to call this assembler dram_init() function now from their board specific initdram() instead. This *should* work, but please test again on those platforms. And it is perhaps a good idea that those boards use some common 405 SDRAM initialization code from cpu/ppc4xx at some time. So further patches welcome here. Signed-off-by: Stefan Roese <sr@denx.de>
96 lines
3.9 KiB
ArmAsm
96 lines
3.9 KiB
ArmAsm
/*------------------------------------------------------------------------+ */
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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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/* */
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/* */
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/* The layout for the PEI JSE board: */
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/* Bank 0 - Flash and SRAM */
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/* Bank 1 - SystemACE */
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/* Bank 2 - not used */
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/* Bank 3 - not used */
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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 - not used */
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/*------------------------------------------------------------------------- */
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#include <ppc4xx.h>
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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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#define cpc0_cr0 0xB1
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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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/* Memory Bank 0 (Flash) initialization */
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/*----------------------------------------------------------------- */
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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 r4,0,0xFFF1 /* BAS=0xFFF,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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