Hi Fred, An update on my progress. After a meeting with Jason Kridner, I solved the Kernel Oops issue that I had. The problem was writing something on the I2C_IRQENABLE_SET register (fixed in this commit <https://github.com/PierrickRauby/BBAI-PRU-I2C/commit/4a39e92be7a375e4109757a98f595514a9e9a622> ). I am now working on the rest of the code; I have confirmed that I don't receive XDR, but I receive XRDY (Figure 24-20 of the TRM <https://www.ti.com/lit/ug/spruhz6l/spruhz6l.pdf?ts=1614612229214&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fdocs%252Funiversalsearch.tsp%253FsearchTerm%253Dspruhz6l>), which I expect to happen. I will continue developing my code and keep you posted. Any progress on your side? Thanks, Pierrick Le jeudi 4 mars 2021 à 16:54:41 UTC-5, pierric...@gadz.org a écrit :
> Hey Fred, > Yeah, I have found the LinuxDroneLab library useful, but the am5729 is > quite different from the AM335x... so no luck for me on that, and I have > not tried to run in on the BBB. Is it not working out of the box? > Have you kept the "pru_i2c_driver_DelayMicros(12);" from the LinuxDroneLab > ? What are you writing to the CON register before polling XRDY? > Thanks > Pierrick > > PS: I am missing the Ti wiki too haha! > Le mercredi 3 mars 2021 à 11:36:51 UTC-5, Fred Frey a écrit : > >> Hey, can I flip it around? Becuase I have a question for *you.* >> >> Have you managed to get this working on a normal BBB? I'm also trying to >> develop an i2c driver for the PRU. It almost looks like we started with the >> same codebase (https://github.com/LinuxDroneLab/pru-i2c-lib), but you >> have obviously modified yours a lot more than I have mine to get it working >> with the 527. >> >> There is definitely some piece missing here. Mine gets to the point of >> setting the I2C_CON register, but then XRDY never comes, and if I read back >> the I2C_CON register, it has lost its master bit. If you look at the TRM, >> it says that the bit is automatically cleared "at the end of a transfer on >> a dedicated stop condition, in case of arbitration lost or when the module >> is configured as a master but addressed as a slave by an external master." >> When I read back the IRQSTATUS register, it just gives back 0. >> >> I've tried trawling through e2e support threads, but the most promising >> ones always link to the TI Processors wiki, which TI decided wasn't worth >> maintaining and shut down about 2 months ago :( >> >> I made another thread begging people for their stash of these old >> articles (https://groups.google.com/u/0/g/beagleboard/c/w6Nd1WmPoSU), so >> that may be of interest to you as well. >> >> I'm sorry if it feels like I'm hijacking your thread, but maybe we can >> help each other out here? >> >> Thanks, >> Fred >> >> >> >> >> >> On Tuesday, 2 March 2021 at 14:58:18 UTC-5 pierric...@gadz.org wrote: >> >>> Hi All, >>> >>> I am trying to develop a PRU driver for I2C on the Beaglebone AI >>> (Ti-am5729). I have some questions about the setup procedure using >>> Interrupt and polling (I am not using DMA). I am not quite sure about the >>> differences between the setup described between section *24.1.5.1.1.1.1 >>> and 24.1.5.1.1.1.2)* and the figure (24.19) of the TRM >>> <https://www.ti.com/lit/ug/spruhz6l/spruhz6l.pdf?ts=1614612229214&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fdocs%252Funiversalsearch.tsp%253FsearchTerm%253Dspruhz6l> >>> . >>> >>> 1- I am not sure about the value to put for I2C_IRQENABLE_SET >>> (referenced in figure 24.19) I have tried with 0x1f (enable XRDY, RRDY, >>> ARDY, NACK, and AL as they are used later). However, I receive a Kernel >>> Oops when I try to run my code " [Feb26 14:54] Unable to handle kernel NULL >>> pointer dereference at virtual address 00000000 >>> >>> [ +0.003725] Internal error: Oops: 5 [#1] PREEMPT SMP ARM >>> >>> genirq: exiting task "irq/114-4807a00" (110) is an active IRQ thread >>> (irq 114)" >>> >>> What value should be used to configure the I2C_IRQENABLE_SET? >>> >>> 2- I have tried to write in the I2C_DATA register but reading the >>> register after always gives 0xD. I have checked the value of >>> I2C_IRQSTATUS_RAW, and it always read 0x10 (XRDY). Am I missing something >>> to write the data? >>> >>> If you want to have a look at my code, it is under this repository >>> https://github.com/PierrickRauby/BBAI-PRU-I2C/blob/main/am572x_pru_i2c_driver.pru1_1.c >>> >>> Thanks for any help you can provide! >>> >>> Pierrick >>> >>> >>> PS: I have posted this same question on the Ti e2e forum a few days ago >>> but I have not solved my issue yet. >>> >> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/942774f8-4226-40eb-bf16-e0f8c42ee8d8n%40googlegroups.com.
