--- /dev/null
+# The QCA4531 is a two stream (2x2) 802.11b/g/n single-band programmable
+# Wi-Fi System-on-Chip (SoC) for the Internet of Things (IoT).
+#
+# Product page:
+# https://www.qualcomm.com/products/qca4531
+#
+# Notes:
+# - MIPS Processor ID (PRId): 0x00019374
+# - 24Kc MIPS processor with 64 KB I-Cache and 32 KB D-Cache,
+# operating at up to 650 MHz
+# - External 16-bit DDR1, operating at up to 200 MHz, DDR2 operating at up
+# to 300 MHz
+# - TRST is not available.
+# - EJTAG PrRst signal is not supported
+# - RESET_L pin B56 on the SoC will reset internal JTAG logic.
+#
+# Pins related for debug and bootstrap:
+# Name Pin Description
+# JTAG
+# JTAG_TCK GPIO0, (A27) Software configurable, default JTAG
+# JTAG_TDI GPIO1, (B23) Software configurable, default JTAG
+# JTAG_TDO GPIO2, (A28) Software configurable, default JTAG
+# JTAG_TMS GPIO3, (A29) Software configurable, default JTAG
+# Reset
+# RESET_L -, (B56) Input only
+# SYS_RST_L GPIO17, (A79) Output reset request or GPIO
+# Bootstrap
+# JTAG_MODE GPIO16, (A78) 0 - JTAG (Default); 1 - EJTAG
+# DDR_SELECT GPIO10, (A57) 0 - DDR2; 1 - DDR1
+# UART
+# UART0_SOUT GPIO10, (A57)
+# UART0_SIN GPIO9, (B49)
+
+# Per default we need to use "none" variant to be able properly "reset init"
+# or "reset halt" the CPU.
+reset_config none srst_pulls_trst
+
+# For SRST based variant we still need proper timings.
+# For ETH part the reset should be asserted at least for 10ms
+# Since there is no other information let's take 100ms to be sure.
+adapter_nsrst_assert_width 100
+
+# according to the SoC documentation it should take at least 5ms from
+# reset end till bootstrap end. In the practice we need 8ms to get JTAG back
+# to live.
+adapter_nsrst_delay 8
+
+if { [info exists CHIPNAME] } {
+ set _CHIPNAME $_CHIPNAME
+} else {
+ set _CHIPNAME qca4531
+}
+
+jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x00000001
+
+set _TARGETNAME $_CHIPNAME.cpu
+target create $_TARGETNAME mips_m4k -endian big -chain-position $_TARGETNAME
+
+# provide watchdog helper.
+proc disable_watchdog { } {
+ mww 0xb8060008 0x0
+}
+
+$_TARGETNAME configure -event halted { disable_watchdog }
+
+# Since PrRst is not supported and SRST will reset complete chip
+# with JTAG engine, we need to reset CPU from CPU itself.
+$_TARGETNAME configure -event reset-assert-pre {
+ halt
+}
+
+$_TARGETNAME configure -event reset-assert {
+ catch "mww 0xb806001C 0x01000000"
+}
+
+# To be able to trigger complete chip reset, in case JTAG is blocked
+# or CPU not responding, we still can use this helper.
+proc full_reset { } {
+ reset_config srst_only
+ reset
+ halt
+ reset_config none
+}
+
+# Section with helpers which can be used by boards
+proc qca4531_ddr2_550_550_init {} {
+ # Clear reset flags for different SoC components
+ mww 0xb806001c 0xfeceffff
+ mww 0xb806001c 0xeeceffff
+ mww 0xb806001c 0xe6ceffff
+
+ # PMU configurations
+ # Internal Switcher
+ mww 0xb8116c40 0x633c8176
+ # Increase the DDR voltage
+ mww 0xb8116c44 0x10200000
+ # XTAL Configurations
+ mww 0xb81162c0 0x4b962100
+ mww 0xb81162c4 0x480
+ mww 0xb81162c8 0x04000144
+ # Recommended PLL configurations
+ mww 0xb81161c4 0x54086000
+ mww 0xb8116244 0x54086000
+
+ # PLL init
+ mww 0xb8050008 0x0131001c
+ mww 0xb8050000 0x40001580
+ mww 0xb8050004 0x40015800
+ mww 0xb8050008 0x0131001c
+ mww 0xb8050000 0x00001580
+ mww 0xb8050004 0x00015800
+ mww 0xb8050008 0x01310000
+ mww 0xb8050044 0x781003ff
+ mww 0xb8050048 0x003c103f
+
+ # DDR2 init
+ mww 0xb8000108 0x401f0042
+ mww 0xb80000b8 0x0000166d
+ mww 0xb8000000 0xcfaaf33b
+ mww 0xb800015c 0x0000000f
+ mww 0xb8000004 0xa272efa8
+ mww 0xb8000018 0x0000ffff
+ mww 0xb80000c4 0x74444444
+ mww 0xb80000c8 0x00000444
+ mww 0xb8000004 0xa210ee28
+ mww 0xb8000004 0xa2b2e1a8
+ mww 0xb8000010 0x8
+ mww 0xb80000bc 0x0
+ mww 0xb8000010 0x10
+ mww 0xb80000c0 0x0
+ mww 0xb8000010 0x40
+ mww 0xb800000c 0x2
+ mww 0xb8000010 0x2
+ mww 0xb8000008 0xb43
+ mww 0xb8000010 0x1
+ mww 0xb8000010 0x8
+ mww 0xb8000010 0x4
+ mww 0xb8000010 0x4
+ mww 0xb8000008 0xa43
+ mww 0xb8000010 0x1
+ mww 0xb800000c 0x382
+ mww 0xb8000010 0x2
+ mww 0xb800000c 0x402
+ mww 0xb8000010 0x2
+ mww 0xb8000014 0x40be
+ mww 0xb800001C 0x20
+ mww 0xb8000020 0x20
+ mww 0xb80000cc 0xfffff
+
+ # UART GPIO programming
+ mww 0xb8040000 0xff30b
+ mww 0xb8040044 0x908
+ mww 0xb8040034 0x160000
+}