diff options
Diffstat (limited to 'board/sysam/stmark2/sbf_dram_init.S')
| -rw-r--r-- | board/sysam/stmark2/sbf_dram_init.S | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/board/sysam/stmark2/sbf_dram_init.S b/board/sysam/stmark2/sbf_dram_init.S new file mode 100644 index 0000000..52abda5 --- /dev/null +++ b/board/sysam/stmark2/sbf_dram_init.S @@ -0,0 +1,119 @@ +/* + * 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 |