Re: Ingenic T31
Great responses everyone. I am feeding these through to a group running openIPC using Ingenic T31. See https://github.com/HackerHomestead/teacup Having openOCD on a dev board like this would be ideal. I think one of us has already found a pin used to put it into JTAG mode. Documentation is not the best! Once I get anything definitive I will post back. Regards Andrew. On Thu, Dec 21, 2023 at 11:41 PM Daniel Glöckner wrote: > On Thu, Dec 21, 2023 at 11:40:26AM +0100, Oleksij Rempel wrote: > > "Ingenic Xburst" is kind of special architecture, not 100% compatible > with MIPS 4K, > > but latest OpenOCD version already includes some of Xburst quirks. With > other words, > > there is a good chance to have some kind of working starting point. > > I know of 3 quirks I had to do to make it work with the JZ4730: > > - Branch target buffer needs to be disabled before doing first branch >in debug mode > > - Writing 1 to ROCC is not ignored > > - Entering Pause-IR and Pause-DR causes changes to IR/DR to be >lost > > I know the last one was fixed for some JTAG adapters by never idling in > Pause-*R, which is possible because we can usually stop TCK. But for which > of the other two issues has a workaround been merged? All I can find is > a commit that says that JZ4780 needs NOPs after DRET. > > Best regards, > > Daniel >
Re: Ingenic T31
On Thu, Dec 21, 2023 at 11:40:26AM +0100, Oleksij Rempel wrote: > "Ingenic Xburst" is kind of special architecture, not 100% compatible with > MIPS 4K, > but latest OpenOCD version already includes some of Xburst quirks. With other > words, > there is a good chance to have some kind of working starting point. I know of 3 quirks I had to do to make it work with the JZ4730: - Branch target buffer needs to be disabled before doing first branch in debug mode - Writing 1 to ROCC is not ignored - Entering Pause-IR and Pause-DR causes changes to IR/DR to be lost I know the last one was fixed for some JTAG adapters by never idling in Pause-*R, which is possible because we can usually stop TCK. But for which of the other two issues has a workaround been merged? All I can find is a commit that says that JZ4780 needs NOPs after DRET. Best regards, Daniel
Re: Ingenic T31
Hi Andrew, Am 20.12.23 um 04:15 schrieb Andrew Walsh: This is a MIPS32 based embedded Linux device with UART pins multiplexed as JTAG. There is very little information provided by Ingenic on the use of these pins as JTAG. I would like to know if it is possible to get openocd working on this chip if we can break out these pins. Your docs say compatible with mips_4k. Here is some info on our core. Do you think it is possible to get openocd working here or is it a lost cause? "Ingenic Xburst" is kind of special architecture, not 100% compatible with MIPS 4K, but latest OpenOCD version already includes some of Xburst quirks. With other words, there is a good chance to have some kind of working starting point. -- Regards, Oleksij
