[U-Boot] Boot from USB support for Kirkwood SOC

[Prafulla Wadaskar]

> -----Original Message-----
> From: xiangfu [mailto:xiangfu.z at gmail.com] 
> Sent: Thursday, June 11, 2009 12:50 PM
> To: Prafulla Wadaskar
> Cc: linux at bohmer.net; U-Boot
> Subject: Re: [U-Boot] Boot from USB support for Kirkwood SOC
> 
> Prafulla Wadaskar wrote:
> > Dear Remy Bohmer
> > 
> > I am going to start "boot from USB Support" development for 
> kirkwood.
> what this "boot from USB Support" means?
Dear Xiangfu Liu
To my development "Boot from USB Support" means, fetching kernel and rfs binaries from the file system/partition on storage connected on USB interface.
There will be native u-boot on NAND or SPI flash that will bring up the system
In the auto boot sequence through h/w triggers on the board like pushbutton/reset key we can initiate bootcmd for "boot_from_USB"
For this I need to support h/w driver for Kirkwood and u-boot USB framework.

This is one of good standalone method to recover system using USB interface (similar to pxeboot)
in case of small embedded systems it would be very useful.

FYI: Kirkwood h/w supports Boot from SF/NANDF/SATA/PEX/UART but not USB :-) as you referenced for JZ4740

Regards..
Prafulla . .

> 
> I know "boot from nand",
> and I know that the Ingenic CPU, support "boot from USB". is 
> the same meaning?
> 
> here is part of JZ4740 cpu data sheet [1]
> --
> 3.7.3   BOOT
> Jz4740 support 3 different boot sources depending on 
> BOOT_SEL0 and BOOT_SEL1 pin values.
> Table 3-29 lists them.
>                              Table 3-29 Boot from 3 boot sources
> 
> BOOT_SEL1 BOOT_SEL0                Boot Source
>     0         0     Boot from NOR flash at CS4
>     0         1     Boot from USB device
>     1         0     Boot from 512 page NAND flash at CS1
>     1         1     Boot from 2k page NAND flash at CS1
> --
> 
> [1] ftp://ftp.ingenic.cn/2soc/Jz4740_ds.pdf
> 
> > To sync with current USB framework in U-boot, and to reduce 
> some rework at my side (since I am new to this driver).
> > May you please provide some guidelines/howto this regard?
> > 
> > FYI below is details about Kirkwood USB controller:  
> > 
> > Kirkwood contains a Universal Serial Bus (USB 2.0) port 
> that includes an embedded USB 2.0 PHY.
> > The USB 2.0 interface contains a single dual-role 
> controller that can 
> > act as a host or a peripheral controller (USB controller). A bridge 
> > connects the controller to the internal Mbus interface (USB bridge).
> > Embedded USB 2.0 PHY features include:
> > ?? 480 Mbps High Speed (HS)/ 12 Mbps Full Speed (FS) and 
> 1.5 Mbps Low 
> > Speed (LS) serial data transmission rates ?? 
> > Synchronization/End-of-Packet (SYNC/EOP) generation and checking ?? 
> > Data and clock recovery from serial stream on the USB ?? 
> Non Return to 
> > Zero Invert (NRZI) encoding/decoding with bit 
> stuffing/unstuffing ?? 
> > Bit stuff error detections ?? Bit stuffing/unstuffing; bit 
> stuff error 
> > detection ?? Holding registers to stage transmit and 
> receive data ?? 
> > Supports USB 2.0 Test Modes ?? Ability to switch between FS and HS 
> > terminations/signaling ?? For more details, refer to the controller 
> > specification document USB-HS High-Speed Controller Core Reference.
> > 
> > Regards..
> > Prafulla . .
> > _______________________________________________
> > U-Boot mailing list
> > U-Boot at lists.denx.de
> > http://lists.denx.de/mailman/listinfo/u-boot
> 
> 
> --
> Best Regards
> Xiangfu Liu
> 
> jabber : xiangfu.z at gmail.com
> skype  : xiangfu.z
>