MediaTek / Ralink

A quite good source for product specs on MediaTek/Ralink SoCs seems to be here: https://deviwiki.com/wiki/Ralink.
OpenWrt specific:
- all MediaTek/Ralink SoCs are merged under the target ramips.
- building a target requires a target-specific firmware (that is, most devices need customized firmware). The kernel is patched with the command line that has the board name in it. This mechanism is similar to what is done for ar71xx platforms.
- browse the source code: https://github.com/openwrt/openwrt/tree/master/target/linux/ramips
: there might still be some historical information in the OpenWrt dev wiki https://dev.openwrt.org/wiki/platforms, but it must be well hidden then. Seems there is nothing that can be found today...

Target	Subtarget	SoC	RAM	Ant	MIPS	Devices
`ramips`	RT288x	RT2880	SDR	2T3R	4KEc	see ToH
	RT3x5x/RT5350	RT3050	SDR	2T2R	24KEc	see ToH
		RT3052	SDR	2T2R	24KEc	see ToH
		RT3350	SDR	1T1R	24KEc	see ToH
		RT3352	SDR/DDR2	2T2R	24KEc	see ToH
		RT5350	SDR	1T1R	24KEc	see ToH
	RT3662/RT3883	RT3662	SDR/DDR2	2T3R	74Kc	see ToH
	RT3662/RT3883	RT3883	SDR/DDR2	3T3R	74Kc	see ToH
	MT7620	MT7620a	DDR2	2T2R	24KEc	see ToH
	MT7620	MT7620n	SDR/DDR1/2	2T2R	24KEc	see ToH
	MT7621	MT7621AT	DDR2/3	n/a	1004Kc	see ToH
	MT7621	MT7621ST	DDR2/3	n/a	1004Kc	see ToH
	MT7628	MT7628	DDR1/2	2T2R	24kec	see ToH
	MT7688	MT7688	DDR1/2	1T1R	24kec	see ToH
`ramips`	n/a	RT6856	?	?	34KEc	see ToH

MT7620 vs. RT5350
- both chips are very similar on the software layer.
- MT7620 is the successor, it's “faster and better”,
  - http://www.mediatek.com/en/products/connectivity/wifi/home-network/wifi-ap/mt7620na
  - http://www.anz.ru/files/mediatek/MT7620_Datasheet.pdf
- RT5350 is still available and cheaper, http://cdn.sparkfun.com/datasheets/Wireless/WiFi/RT5350.pdf
- see here for a comparison: http://vonger.cn/?p=242
MT7621
- 2 cores, 4 threads:
  - MT7621AT
- 1 core, 2 threads:
  - MT7621ST, MT7621NT
- SoC does not include a Wifi subsystem
- https://www.mediatek.com/products/homeNetworking/mt7621
- https://deviwiki.com/wiki/MediaTek_MT7621
MT7628
- MT7628A: Full function with external DRAM
- MT7628K: Embedded 8MB DRAM and L-shape
- MT7628N: Same as MT7628A, but without PCle and IoT modes

On MT7620A and likely other Ralink / Mediatek SOCs, the RGMII delay is set with the Port I control register in the GSW (gigabit switch) subsystem

for boards with uboot and an available console (option 4?), the register can be read with the command

  md 0x10117014 1

and the following bits tell you the OEM bootloader / chip defaults

For a complete explanation, look for the register 0x7014 in the MT7620 Programming Guide

example:

10117014: 1f08000c

c -→ 1100 -→ TX delay only

8 -→ PHY_BASE address

1f -→ internal PHYs disabled

Remember: You have to read bits from right to left. For example 1f08000c in binary becomes 00011111000010000000000000001100

0001 1111 0000 1000 0000 0000 0000 1100
   |    |    |    |    |    |    |    |   
  28   24   20   16   12    8    4    0

http://www.mediatek.com/_en/01_products/04_pro.php?sn=1031
TC3085/TC3086 = AFE (Analog Front-End) for ADSL2+
TC3162L2M It incorporates a 32-bit network processor and a DMT (Discrete Multi-Tone)-engine for ADSL2+
TC3162LEM It incorporates a 32-bit network processor and a DMT (Discrete Multi-Tone)-engine for ADSL2+

RT63260 The RT63260 is a highly integrated single-chip solution combining AFE (Analog Front End) chip technology and an ADSL2/2+ wired ADSL modem application together on one chip. It includes a 32-bit network processor and a Discrete Multi-Tone (DMT) engine for ADSL
RT63365
- combine with RT63087 AFE (Analog Front-End) for VDSL2
RT63368 It incorporates a MIPS 34Kc CPU and a DMT (Discrete Multi-Tone)-engine for VDSL2
- combine with RT63087 AFE (Analog Front-End) for VDSL2
RT65168 It incorporates a MIPS 34Kc CPU and a DMT (Discrete Multi-Tone)-engine for VDSL2
- combine with RT63095 AFE (Analog Front-End) for VDSL2

unknown

The list of related devices: MediaTek, MT7620a, MT7620N,

General