board/csb472/init.S

/*
 * SPDX-License-Identifier:	GPL-2.0	IBM-pibs
 */
#include <config.h>
#include <asm/ppc4xx.h>

#include <ppc_asm.tmpl>
#include <ppc_defs.h>

#include <asm/cache.h>
#include <asm/mmu.h>

#define LI32(reg,val) \
	addis   reg,0,val@h;\
	ori     reg,reg,val@l

#define WDCR_EBC(reg,val) \
	addi    r4,0,reg;\
	mtdcr   EBC0_CFGADDR,r4;\
	addis   r4,0,val@h;\
	ori     r4,r4,val@l;\
	mtdcr   EBC0_CFGDATA,r4

#define WDCR_SDRAM(reg,val) \
	addi    r4,0,reg;\
	mtdcr   SDRAM0_CFGADDR,r4;\
	addis   r4,0,val@h;\
	ori     r4,r4,val@l;\
	mtdcr   SDRAM0_CFGDATA,r4

/******************************************************************************
 * 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) / CONFIG_SYS_CACHELINE_SIZE) + 2)
	mtctr	r4
..ebcloop:
	icbt	r0, r3			/* prefetch cache line for addr in r3*/
	addi	r3, r3, CONFIG_SYS_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 CPC0_CR0
	 *******************************************************************/
	LI32(r4, 0x00c01030)
	mtdcr	CPC0_CR0, r4

	/********************************************************************
	 * Setup CPC0_CR1: Change PCIINT signal to PerWE
	 *******************************************************************/
	mfdcr	r4, CPC0_CR1
	ori	r4, r4, 0x4000
	mtdcr	CPC0_CR1, r4

	/********************************************************************
	 * Setup External Bus Controller (EBC).
	 *******************************************************************/
	WDCR_EBC(EBC0_CFG, 0xd84c0000)
	/********************************************************************
	 * Memory Bank 0 (Intel 28F640J3 Flash) initialization
	 *******************************************************************/
	/*WDCR_EBC(PB1AP, 0x03055200)*/
	/*WDCR_EBC(PB1AP, 0x04055200)*/
	WDCR_EBC(PB1AP, 0x08055200)
	WDCR_EBC(PB0CR, 0xff87a000)
	/********************************************************************
	 * Memory Bank 3 (Xilinx XC95144 CPLD) initialization
	 *******************************************************************/
	/*WDCR_EBC(PB3AP, 0x07869200)*/
	WDCR_EBC(PB3AP, 0x04055200)
	WDCR_EBC(PB3CR, 0xf081c000)
	/********************************************************************
	 * Memory Bank 1,2,4-7 (Unused) initialization
	 *******************************************************************/
	WDCR_EBC(PB1AP, 0)
	WDCR_EBC(PB1CR, 0)
	WDCR_EBC(PB2AP, 0)
	WDCR_EBC(PB2CR, 0)
	WDCR_EBC(PB4AP, 0)
	WDCR_EBC(PB4CR, 0)
	WDCR_EBC(PB5AP, 0)
	WDCR_EBC(PB5CR, 0)
	WDCR_EBC(PB6AP, 0)
	WDCR_EBC(PB6CR, 0)
	WDCR_EBC(PB7AP, 0)
	WDCR_EBC(PB7CR, 0)

	/* 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.
 *
 * Notes:	Does NOT use the stack.
 *****************************************************************************/
	.section ".text"
	.align	2
	.globl	sdram_init
	.type	sdram_init, @function
sdram_init:

	/*
	 * Disable memory controller to allow
	 * values to be changed.
	 */
	WDCR_SDRAM(SDRAM0_CFG, 0x00000000)

	/*
	 * Configure Memory Banks
	 */
	WDCR_SDRAM(SDRAM0_B0CR, 0x00062001)
	WDCR_SDRAM(SDRAM0_B1CR, 0x00000000)
	WDCR_SDRAM(SDRAM0_B2CR, 0x00000000)
	WDCR_SDRAM(SDRAM0_B3CR, 0x00000000)

	/*
	 * Set up SDTR1 (SDRAM Timing Register)
	 */
	WDCR_SDRAM(SDRAM0_TR, 0x00854009)

	/*
	 * Set RTR (Refresh Timing Register)
	 */
	WDCR_SDRAM(SDRAM0_RTR,   0x10000000)
	/* WDCR_SDRAM(SDRAM0_RTR,   0x05f00000) */

	/********************************************************************
	 * 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.
	 *******************************************************************/
	WDCR_SDRAM(SDRAM0_CFG,0x80800000)

..sdri_done:
	blr				/* Return to calling function */
.Lfe1:	.size	sdram_init,.Lfe1-sdram_init
/* end sdram_init() */