riscv-openocd/tcl/board/tp-link_tl-mr3020.cfg

source [find target/atheros_ar9331.cfg]

proc ar9331_25mhz_pll_init {} {
	mww 0xb8050008 0x00018004	;# bypass PLL; AHB_POST_DIV - ratio 4
	mww 0xb8050004 0x00000352	;# 34000(ns)/40ns(25MHz) = 0x352 (850)
	mww 0xb8050000 0x40818000	;# Power down control for CPU PLL
					;# OUTDIV | REFDIV | DIV_INT
	mww 0xb8050010 0x001003e8	;# CPU PLL Dither FRAC Register
					;# (disabled?)
	mww 0xb8050000 0x00818000	;# Power on | OUTDIV | REFDIV | DIV_INT
	mww 0xb8050008 0x00008000	;# remove bypass;
					;# AHB_POST_DIV - ratio 2
}

proc ar9331_ddr1_init {} {
	mww 0xb8000000 0x7fbc8cd0       ;# DDR_CONFIG - lots of DRAM confs
	mww 0xb8000004 0x9dd0e6a8	;# DDR_CONFIG2 - more DRAM confs

	mww 0xb8000010 0x8	;# Forces a PRECHARGE ALL cycle
	mww 0xb8000008 0x133	;# mode reg: 0x133 - default
	mww 0xb8000010 0x1	;# Forces an MRS update cycl
	mww 0xb800000c 0x2	;# Extended mode register value.
				;# default 0x2 - Reset to weak driver, DLL on
	mww 0xb8000010 0x2	;# Forces an EMRS update cycle
	mww 0xb8000010 0x8	;# Forces a PRECHARGE ALL cycle
	mww 0xb8000008 0x33	;# mode reg: remove some bit?
	mww 0xb8000010 0x1	;# Forces an MRS update cycl
	mww 0xb8000014 0x4186	;# enable refres: bit(14) - set refresh rate
	mww 0xb800001c 0x8	;# This register is used along with DQ Lane 0,
				;# DQ[7:0], DQS_0
	mww 0xb8000020 0x9	;# This register is used along with DQ Lane 1,
				;# DQ[15:8], DQS_1.
	mww 0xb8000018 0xff	;# DDR read and capture bit mask.
				;# Each bit represents a cycle of valid data.
}

$_TARGETNAME configure -event reset-init {
	ar9331_25mhz_pll_init
	sleep 1
	ar9331_ddr1_init
}

set ram_boot_address 0xa0000000
$_TARGETNAME configure -work-area-phys 0xa1FFE000 -work-area-size 0x1000