u-boot/arch/mips/mach-mt7620/lowlevel_init.S
Stefan Roese a8b0bf6313 mips: mt76xx: lowlevel_init.S: Add missing memory controller reset in DDR init
This fixes an issue which has been noticed on the Gardena board, with
the watchdog enabled, where the watdchdog reset (after a system hang)
did result in reporting of 2.9 GiB and a hang after this. With this
patch applied the memory controller is correctly reset and initialized
again even after a watchdog reset.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-11-18 16:02:22 +01:00

328 lines
6 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (c) 2018 Stefan Roese <sr@denx.de>
*
* This code is mostly based on the code extracted from this MediaTek
* github repository:
*
* https://github.com/MediaTek-Labs/linkit-smart-uboot.git
*
* I was not able to find a specific license or other developers
* copyrights here, so I can't add them here.
*/
#include <config.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/addrspace.h>
#include <asm/asm.h>
#include "mt76xx.h"
#ifndef BIT
#define BIT(nr) (1 << (nr))
#endif
#define DELAY_USEC(us) ((us) / 100)
#define DDR_CFG1_CHIP_WIDTH_MASK (0x3 << 16)
#define DDR_CFG1_BUS_WIDTH_MASK (0x3 << 12)
#if defined(CONFIG_ONBOARD_DDR2_SIZE_256MBIT)
#define DDR_CFG1_SIZE_VAL 0x222e2323
#define DDR_CFG4_SIZE_VAL 7
#endif
#if defined(CONFIG_ONBOARD_DDR2_SIZE_512MBIT)
#define DDR_CFG1_SIZE_VAL 0x22322323
#define DDR_CFG4_SIZE_VAL 9
#endif
#if defined(CONFIG_ONBOARD_DDR2_SIZE_1024MBIT)
#define DDR_CFG1_SIZE_VAL 0x22362323
#define DDR_CFG4_SIZE_VAL 9
#endif
#if defined(CONFIG_ONBOARD_DDR2_SIZE_2048MBIT)
#define DDR_CFG1_SIZE_VAL 0x223a2323
#define DDR_CFG4_SIZE_VAL 9
#endif
#if defined(CONFIG_ONBOARD_DDR2_CHIP_WIDTH_8BIT)
#define DDR_CFG1_CHIP_WIDTH_VAL (0x1 << 16)
#endif
#if defined(CONFIG_ONBOARD_DDR2_CHIP_WIDTH_16BIT)
#define DDR_CFG1_CHIP_WIDTH_VAL (0x2 << 16)
#endif
#if defined(CONFIG_ONBOARD_DDR2_BUS_WIDTH_16BIT)
#define DDR_CFG1_BUS_WIDTH_VAL (0x2 << 12)
#endif
#if defined(CONFIG_ONBOARD_DDR2_BUS_WIDTH_32BIT)
#define DDR_CFG1_BUS_WIDTH_VAL (0x3 << 12)
#endif
.set noreorder
LEAF(lowlevel_init)
/* Load base addresses as physical addresses for later usage */
li s0, CKSEG1ADDR(MT76XX_SYSCTL_BASE)
li s1, CKSEG1ADDR(MT76XX_MEMCTRL_BASE)
li s2, CKSEG1ADDR(MT76XX_RGCTRL_BASE)
/* polling CPLL is ready */
li t1, DELAY_USEC(1000000)
la t5, MT76XX_ROM_STATUS_REG
1:
lw t2, 0(t5)
andi t2, t2, 0x1
bnez t2, CPLL_READY
subu t1, t1, 1
bgtz t1, 1b
nop
la t0, MT76XX_CLKCFG0_REG
lw t3, 0(t0)
ori t3, t3, 0x1
sw t3, 0(t0)
b CPLL_DONE
nop
CPLL_READY:
la t0, MT76XX_CLKCFG0_REG
lw t1, 0(t0)
li t2, ~0x0c
and t1, t1, t2
ori t1, t1, 0xc
sw t1, 0(t0)
la t0, MT76XX_DYN_CFG0_REG
lw t3, 0(t0)
li t5, ~((0x0f << 8) | (0x0f << 0))
and t3, t3, t5
li t5, (10 << 8) | (1 << 0)
or t3, t3, t5
sw t3, 0(t0)
la t0, MT76XX_CLKCFG0_REG
lw t3, 0(t0)
li t4, ~0x0F
and t3, t3, t4
ori t3, t3, 0xc
sw t3, 0(t0)
lw t3, 0(t0)
ori t3, t3, 0x08
sw t3, 0(t0)
CPLL_DONE:
/* Reset MC */
lw t2, 0x34(s0)
ori t2, BIT(10)
sw t2, 0x34(s0)
nop
/*
* SDR and DDR initialization: delay 200us
*/
li t0, DELAY_USEC(200 + 40)
li t1, 0x1
1:
sub t0, t0, t1
bnez t0, 1b
nop
/* set DRAM IO PAD for MT7628IC */
/* DDR LDO Enable */
lw t4, 0x100(s2)
li t2, BIT(31)
or t4, t4, t2
sw t4, 0x100(s2)
lw t4, 0x10c(s2)
j LDO_1P8V
nop
LDO_1P8V:
li t2, ~BIT(6)
and t4, t4, t2
sw t4, 0x10c(s2)
j DDRLDO_SOFT_START
LDO_2P5V:
/* suppose external DDR1 LDO 2.5V */
li t2, BIT(6)
or t4, t4, t2
sw t4, 0x10c(s2)
DDRLDO_SOFT_START:
lw t2, 0x10c(s2)
li t3, BIT(16)
or t2, t2, t3
sw t2, 0x10c(s2)
li t3, DELAY_USEC(250*50)
LDO_DELAY:
subu t3, t3, 1
bnez t3, LDO_DELAY
nop
lw t2, 0x10c(s2)
li t3, BIT(18)
or t2, t2, t3
sw t2, 0x10c(s2)
SET_RG_BUCK_FPWM:
lw t2, 0x104(s2)
ori t2, t2, BIT(10)
sw t2, 0x104(s2)
DDR_PAD_CFG:
/* clean CLK PAD */
lw t2, 0x704(s2)
li t8, 0xfffff0f0
and t2, t2, t8
/* clean CMD PAD */
lw t3, 0x70c(s2)
li t8, 0xfffff0f0
and t3, t3, t8
/* clean DQ IPAD */
lw t4, 0x710(s2)
li t8, 0xfffff8ff
and t4, t4, t8
/* clean DQ OPAD */
lw t5, 0x714(s2)
li t8, 0xfffff0f0
and t5, t5, t8
/* clean DQS IPAD */
lw t6, 0x718(s2)
li t8, 0xfffff8ff
and t6, t6, t8
/* clean DQS OPAD */
lw t7, 0x71c(s2)
li t8, 0xfffff0f0
and t7, t7, t8
lw t9, 0xc(s0)
srl t9, t9, 16
andi t9, t9, 0x1
bnez t9, MT7628_AN_DDR1_PAD
MT7628_KN_PAD:
li t8, 0x00000303
or t2, t2, t8
or t3, t3, t8
or t5, t5, t8
or t7, t7, t8
li t8, 0x00000000
or t4, t4, t8
or t6, t6, t8
j SET_PAD_CFG
MT7628_AN_DDR1_PAD:
lw t1, 0x10(s0)
andi t1, t1, 0x1
beqz t1, MT7628_AN_DDR2_PAD
li t8, 0x00000c0c
or t2, t2, t8
li t8, 0x00000202
or t3, t3, t8
li t8, 0x00000707
or t5, t5, t8
li t8, 0x00000c0c
or t7, t7, t8
li t8, 0x00000000
or t4, t4, t8
or t6, t6, t8
j SET_PAD_CFG
MT7628_AN_DDR2_PAD:
li t8, 0x00000c0c
or t2, t2, t8
li t8, 0x00000202
or t3, t3, t8
li t8, 0x00000404
or t5, t5, t8
li t8, 0x00000c0c
or t7, t7, t8
li t8, 0x00000000 /* ODT off */
or t4, t4, t8
or t6, t6, t8
SET_PAD_CFG:
sw t2, 0x704(s2)
sw t3, 0x70c(s2)
sw t4, 0x710(s2)
sw t5, 0x714(s2)
sw t6, 0x718(s2)
sw t7, 0x71c(s2)
/*
* DDR initialization: reset pin to 0
*/
lw t2, 0x34(s0)
and t2, ~BIT(10)
sw t2, 0x34(s0)
nop
/*
* DDR initialization: wait til reg DDR_CFG1 bit 21 equal to 1 (ready)
*/
DDR_READY:
li t1, DDR_CFG1_REG
lw t0, 0(t1)
nop
and t2, t0, BIT(21)
beqz t2, DDR_READY
nop
/*
* DDR initialization
*
* Only DDR2 supported right now. DDR2 support can be added, once
* boards using it will get added to mainline U-Boot.
*/
li t1, DDR_CFG2_REG
lw t0, 0(t1)
nop
and t0, ~BIT(30)
and t0, ~(7 << 4)
or t0, (4 << 4)
or t0, BIT(30)
or t0, BIT(11)
sw t0, 0(t1)
nop
li t1, DDR_CFG3_REG
lw t2, 0(t1)
/* Disable ODT; reference board ok, ev board fail */
and t2, ~BIT(6)
or t2, BIT(2)
li t0, DDR_CFG4_REG
lw t1, 0(t0)
li t2, ~(0x01f | 0x0f0)
and t1, t1, t2
ori t1, t1, DDR_CFG4_SIZE_VAL
sw t1, 0(t0)
nop
/*
* DDR initialization: config size and width on reg DDR_CFG1
*/
li t6, DDR_CFG1_SIZE_VAL
and t6, ~DDR_CFG1_CHIP_WIDTH_MASK
or t6, DDR_CFG1_CHIP_WIDTH_VAL
/* CONFIG DDR_CFG1[13:12] about TOTAL WIDTH */
and t6, ~DDR_CFG1_BUS_WIDTH_MASK
or t6, DDR_CFG1_BUS_WIDTH_VAL
li t5, DDR_CFG1_REG
sw t6, 0(t5)
nop
/*
* DDR: enable self auto refresh for power saving
* enable it by default for both RAM and ROM version (for CoC)
*/
lw t1, 0x14(s1)
nop
and t1, 0xff000000
or t1, 0x01
sw t1, 0x14(s1)
nop
lw t1, 0x10(s1)
nop
or t1, 0x10
sw t1, 0x10(s1)
nop
jr ra
nop
END(lowlevel_init)