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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
+ *
+ *****************************************************************************/
+#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>
+
+/******************************************************************************
+ * Function:	ext_bus_cntlr_init
+ *
+ * Description:	Configures EBC Controller and a few basic chip selects.
+ *
+ *		CS0 is setup to get the Boot Flash out of the addresss range
+ *		so that we may setup a stack.  CS7 is setup so that we can
+ *		access and reset the hardware watchdog.
+ *
+ *		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.
+ *
+ * Notes:	Does NOT use the stack.
+ *****************************************************************************/
+	.section ".text"
+	.align	2
+	.globl	ext_bus_cntlr_init
+	.type	ext_bus_cntlr_init, @function
+ext_bus_cntlr_init:
+	mflr	r0
+	/********************************************************************
+	 * Prefetch entire ext_bus_cntrl_init function into the icache.
+	 * This is necessary because we are going to change the same CS we
+	 * are executing from.  Otherwise a CPU lockup may occur.
+	 *******************************************************************/
+	bl	..getAddr
+..getAddr:
+	mflr	r3			/* get address of ..getAddr */
+
+	/* Calculate number of cache lines for this function */
+	addi	r4, 0, (((.Lfe0 - ..getAddr) / CFG_CACHELINE_SIZE) + 2)
+	mtctr	r4
+..ebcloop:
+	icbt	r0, r3			/* prefetch cache line for addr in r3*/
+	addi	r3, r3, CFG_CACHELINE_SIZE /* move to next cache line */
+	bdnz	..ebcloop		/* continue for $CTR 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		/* wait 200us from reset */
+	mtctr	r3
+..spinlp:
+	bdnz	..spinlp		/* spin loop */
+
+	/********************************************************************
+	 * Setup External Bus Controller (EBC).
+	 *******************************************************************/
+	addi	r3, 0, epcr
+	mtdcr	ebccfga, r3
+	addis	r4, 0, 0xb040		/* Device base timeout = 1024 cycles */
+	ori	r4, r4, 0x0		/* Drive CS with external master */
+	mtdcr	ebccfgd, r4
+
+	/********************************************************************
+	 * Change PCIINT signal to PerWE
+	 *******************************************************************/
+	mfdcr	r4, cntrl1
+	ori	r4, r4, 0x4000
+	mtdcr	cntrl1, r4
+
+	/********************************************************************
+	 * Memory Bank 0 (Flash Bank 0) initialization
+	 *******************************************************************/
+	addi	r3, 0, pb0ap
+	mtdcr	ebccfga, r3
+	addis	r4, 0, CFG_W7O_EBC_PB0AP@h
+	ori	r4, r4, CFG_W7O_EBC_PB0AP@l
+	mtdcr	ebccfgd, r4
+
+	addi	r3, 0, pb0cr
+	mtdcr	ebccfga, r3
+	addis	r4, 0, CFG_W7O_EBC_PB0CR@h
+	ori	r4, r4, CFG_W7O_EBC_PB0CR@l
+	mtdcr	ebccfgd, r4
+
+	/********************************************************************
+	 * Memory Bank 7 LEDs - NEEDED BECAUSE OF HW WATCHDOG AND LEDs.
+	 *******************************************************************/
+	addi	r3, 0, pb7ap
+	mtdcr	ebccfga, r3
+	addis	r4, 0, CFG_W7O_EBC_PB7AP@h
+	ori	r4, r4, CFG_W7O_EBC_PB7AP@l
+	mtdcr	ebccfgd, r4
+
+	addi	r3, 0, pb7cr
+	mtdcr	ebccfga, r3
+	addis	r4, 0, CFG_W7O_EBC_PB7CR@h
+	ori	r4, r4, CFG_W7O_EBC_PB7CR@l
+	mtdcr	ebccfgd, r4
+
+	/* We are all done */
+	mtlr	r0			/* Restore link register */
+	blr				/* Return to calling function */
+.Lfe0:	.size	ext_bus_cntlr_init,.Lfe0-ext_bus_cntlr_init
+/* end ext_bus_cntlr_init() */
+
+/******************************************************************************
+ * Function:	sdram_init
+ *
+ * Description:	Configures SDRAM memory banks.
+ *
+ *		Serial Presence Detect, "SPD," reads the SDRAM EEPROM
+ *		via the IIC bus and then configures the SDRAM memory
+ *		banks appropriately. If Auto Memory Configuration is
+ *		is not used, it is assumed that a 4MB 11x8x2, non-ECC,
+ *		SDRAM is soldered down.
+ *
+ * Notes:	Expects that the stack is already setup.
+ *****************************************************************************/
+	.section ".text"
+	.align	2
+	.globl	sdram_init
+	.type	sdram_init, @function
+sdram_init:
+	/* save the return info on stack */
+	mflr	r0			/* Get link register */
+	stwu	r1, -8(r1)		/* Save back chain and move SP */
+	stw	r0, +12(r1)		/* Save link register */
+
+	/*
+	 * First call spd_sdram to try to init SDRAM according to the
+	 * contents of the SPD EEPROM.  If the SPD EEPROM is blank or
+	 * erronious, spd_sdram returns 0 in R3.
+	 */
+	bl	spd_sdram
+	addic.	r3, r3, 0		/* Check for error, save dram size */
+	bne	..sdri_done		/* If it worked, we're done... */
+
+	/********************************************************************
+	 * If SPD detection fails, we'll default to 4MB, 11x8x2, as this
+	 * is the SMALLEST SDRAM size the 405 supports.  We can do this
+	 * because W7O boards have soldered on RAM, and there will always
+	 * be some amount present.  If we were using DIMMs, we should hang
+	 * the board instead, since it doesn't have any RAM to continue
+	 * running with.
+	 *******************************************************************/
+
+	/*
+	 * Disable memory controller to allow
+	 * values to be changed.
+	 */
+	addi    r3, 0, mem_mcopt1
+	mtdcr   memcfga, r3
+	addis   r4, 0, 0x0
+	ori     r4, r4, 0x0
+	mtdcr   memcfgd, r4
+
+	/*
+	 * Set MB0CF for ext bank 0. (0-4MB) Address Mode 5 since 11x8x2
+	 * All other banks are disabled.
+	 */
+	addi	r3, 0, mem_mb0cf
+	mtdcr	memcfga, r3
+	addis	r4, 0, 0x0000		/* BA=0x0, SZ=4MB */
+	ori	r4, r4, 0x8001		/* Mode is 5, 11x8x2or4, BE=Enabled */
+	mtdcr	memcfgd, r4
+
+	/* Clear MB1CR,MB2CR,MB3CR to turn other banks off */
+	addi	r4, 0, 0		/* Zero the data reg */
+
+	addi	r3, r3, 4		/* Point to MB1CF reg */
+	mtdcr	memcfga, r3		/* Set the address */
+	mtdcr	memcfgd, r4		/* Zero the reg */
+
+	addi	r3, r3, 4		/* Point to MB2CF reg */
+	mtdcr	memcfga, r3		/* Set the address */
+	mtdcr	memcfgd, r4		/* Zero the reg */
+
+	addi	r3, r3, 4		/* Point to MB3CF reg */
+	mtdcr	memcfga, r3		/* Set the address */
+	mtdcr	memcfgd, r4		/* Zero the reg */
+
+	/********************************************************************
+	 * Set the SDRAM Timing reg, SDTR1 and the refresh timer reg, RTR.
+	 * To set the appropriate timings, we assume sdram is
+	 * 100MHz (pc100 compliant).
+	 *******************************************************************/
+
+	/*
+	 * Set up SDTR1
+	 */
+	addi    r3, 0, mem_sdtr1
+	mtdcr   memcfga, r3
+	addis   r4, 0, 0x0086		/* SDTR1 value for 100Mhz */
+	ori     r4, r4, 0x400D
+	mtdcr   memcfgd, r4
+
+	/*
+	 * Set RTR
+	 */
+	addi    r3, 0, mem_rtr
+	mtdcr   memcfga, r3
+	addis   r4, 0, 0x05F0		/* RTR refresh val = 15.625ms@100Mhz */
+	mtdcr   memcfgd, r4
+
+	/********************************************************************
+	 * 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		/* Wait 200us from reset */
+	mtctr   r3
+..spinlp2:
+	bdnz    ..spinlp2		/* spin loop */
+
+	/********************************************************************
+	 * Set memory controller options reg, MCOPT1.
+	 *******************************************************************/
+	addi    r3, 0, mem_mcopt1
+	mtdcr   memcfga, r3
+	addis   r4, 0, 0x80E0		/* DC_EN=1,SRE=0,PME=0,MEMCHK=0 */
+	ori     r4, r4, 0x0000		/* REGEN=0,DRW=00,BRPF=01,ECCDD=1 */
+	mtdcr   memcfgd, r4		/* EMDULR=1 */
+
+..sdri_done:
+	/* restore and return */
+	lwz	r0, +12(r1)		/* Get saved link register */
+	addi	r1, r1, +8		/* Remove frame from stack */
+	mtlr	r0			/* Restore link register */
+	blr				/* Return to calling function */
+.Lfe1:	.size	sdram_init,.Lfe1-sdram_init
+/* end sdram_init() */
+