blob: 52abda5c3c40bb77f8ec457aca159a542f5009fe [file] [log] [blame]
/*
* Board-specific early ddr/sdram init.
*
* (C) Copyright 2017 Angelo Dureghello <angelo@sysam.it>
*
* SPDX-License-Identifier: GPL-2.0+
*/
.equ PPMCR0, 0xfc04002d
.equ MSCR_SDRAMC, 0xec094060
.equ MISCCR2, 0xec09001a
.equ DDR_RCR, 0xfc0b8180
.equ DDR_PADCR, 0xfc0b81ac
.equ DDR_CR00, 0xfc0b8000
.equ DDR_CR06, 0xfc0b8018
.equ DDR_CR09, 0xfc0b8024
.equ DDR_CR40, 0xfc0b80a0
.equ DDR_CR45, 0xfc0b80b4
.equ DDR_CR56, 0xfc0b80e0
.global sbf_dram_init
.text
sbf_dram_init:
/* CD46 = DDR on */
move.l #PPMCR0, %a1
move.b #46, (%a1)
/* stmark 2, max drive strength */
move.l #MSCR_SDRAMC, %a1
move.b #1, (%a1)
/*
* use cpu clock, seems more realiable
*
* DDR2 clock is serviced from DDR controller as input clock / 2
* so, if clock comes from
* vco, i.e. 480(vco) / 2, so ddr clock is 240 Mhz (measured)
* cpu, i.e. 250(cpu) / 2, so ddr clock is 125 Mhz (measured)
*
* .
* / \ DDR2 can't be clocked lower than 125Mhz
* / ! \ DDR2 init must pass further i/dcache enable test
* /_____\
* WARNING
*/
/* cpu / 2 = 125 Mhz for 480 Mhz pll */
move.l #MISCCR2, %a1
move.w #0xa01d, (%a1)
/* DDR force sw reset settings */
move.l #DDR_RCR, %a1
move.l #0x00000000, (%a1)
move.l #0x40000000, (%a1)
/*
* PAD_ODT_CS: for us seems both 1(75 ohm) and 2(150ohm) are good,
* 500/700 mV are ok
*/
move.l #DDR_PADCR, %a1
move.l #0x01030203, (%a1) /* as freescale tower */
move.l #DDR_CR00, %a1
move.l #0x01010101, (%a1)+ /* 0x00 */
move.l #0x00000101, (%a1)+ /* 0x04 */
move.l #0x01010100, (%a1)+ /* 0x08 */
move.l #0x01010000, (%a1)+ /* 0x0C */
move.l #0x00010101, (%a1)+ /* 0x10 */
move.l #DDR_CR06, %a1
move.l #0x00010100, (%a1)+ /* 0x18 */
move.l #0x00000001, (%a1)+ /* 0x1C */
move.l #0x01000001, (%a1)+ /* 0x20 */
move.l #0x00000100, (%a1)+ /* 0x24 */
move.l #0x00010001, (%a1)+ /* 0x28 */
move.l #0x00000200, (%a1)+ /* 0x2C */
move.l #0x01000002, (%a1)+ /* 0x30 */
move.l #0x00000000, (%a1)+ /* 0x34 */
move.l #0x00000100, (%a1)+ /* 0x38 */
move.l #0x02000100, (%a1)+ /* 0x3C */
move.l #0x02000407, (%a1)+ /* 0x40 */
move.l #0x02030007, (%a1)+ /* 0x44 */
move.l #0x02000100, (%a1)+ /* 0x48 */
move.l #0x0A030203, (%a1)+ /* 0x4C */
move.l #0x00020708, (%a1)+ /* 0x50 */
move.l #0x00050008, (%a1)+ /* 0x54 */
move.l #0x04030002, (%a1)+ /* 0x58 */
move.l #0x00000004, (%a1)+ /* 0x5C */
move.l #0x020A0000, (%a1)+ /* 0x60 */
move.l #0x0C00000E, (%a1)+ /* 0x64 */
move.l #0x00002004, (%a1)+ /* 0x68 */
move.l #0x00000000, (%a1)+ /* 0x6C */
move.l #0x00100010, (%a1)+ /* 0x70 */
move.l #0x00100010, (%a1)+ /* 0x74 */
move.l #0x00000000, (%a1)+ /* 0x78 */
move.l #0x07990000, (%a1)+ /* 0x7C */
move.l #DDR_CR40, %a1
move.l #0x00000000, (%a1)+ /* 0xA0 */
move.l #0x00C80064, (%a1)+ /* 0xA4 */
move.l #0x44520002, (%a1)+ /* 0xA8 */
move.l #0x00C80023, (%a1)+ /* 0xAC */
move.l #DDR_CR45, %a1
move.l #0x0000C350, (%a1) /* 0xB4 */
move.l #DDR_CR56, %a1
move.l #0x04000000, (%a1)+ /* 0xE0 */
move.l #0x03000304, (%a1)+ /* 0xE4 */
move.l #0x40040000, (%a1)+ /* 0xE8 */
move.l #0xC0004004, (%a1)+ /* 0xEC */
move.l #0x0642C000, (%a1)+ /* 0xF0 */
move.l #0x00000642, (%a1)+ /* 0xF4 */
move.l #DDR_CR09, %a1
tpf
move.l #0x01000100, (%a1) /* 0x24 */
move.l #0x2000, %d1
bsr asm_delay
rts