Hello Ralf, thanks for your advice. I've patched the driver *inmates/lib/arm-common/uart-imx.c* and everything it works.
Speaking in general, I find a bit strange that there aren't drivers ready to develop a bare-metal application into inmate cell (like for M4 into MCUXpresso SDK). Do you know if in the future there will be implemented this "software layer"? For example if I want to use other peripherals (SPI, I2C, etc...)... there is something? Thank you. Waiting a feedback from you. Regards. Stefano On Thursday, April 29, 2021 at 6:16:28 PM UTC+2 Ralf Ramsauer wrote: > Hi Stefano, > > On 29/04/2021 10:45, Stefano Gurrieri wrote: > > Hello, > > > > I’ve experimented succefully jailhouse on my target (var-som-mx8m-mini + > > symphony carrier board); specifically I’ve tested a second linux and > > other demos (ivshmem-demo, gic-demo...). > > > > Furthermore, I’ve cross-compiled a very easy bare-metal application, but > > I’m not able to use UART3 (second uart) from this cell (linux root cell > > send correctly debug messages on UART4 -first uart-). Attached you can > find: > > > > - *imx8mm-uart-demo.c* my config cell > > > > - *uart-demo.c* demo loaded into > > inmate cell > > > > Runtime, after enabling jailhouse, I enter: > > > > jailhouse cell create /usr/share/jailhouse/cells/imx8mm-uart-demo.cell > > > > jailhouse cell load 1 /usr/share/jailhouse/inmates/uart-demo.bin > > > > jailhouse cell start 1 > > > > In theory, I should be able to see “/printk(”blablabla”)/ messages on my > > uart3 console (the second serial console), but I don’t see anything. > > > > *** > > > > Questions: > > > > 1. Have you some idea? What I got wrong? > > > > 2. The config cell seems correct, but I’m asking who initialize uart3 > > serial? Linux? Because if it’s linux, the uart3 is disabled in the dtb. > > Is it possible initialize uart3 serial also into jailhouse? > > If it's disabled in the DT, and nobody initialised it before, then yes, > there's a certain chance that the UART arrives unconfigured in the cell. > > Have a look at inmates/lib/arm-common/uart-imx.c . The init routine > currently does nothing. IOW, you either need to patch the driver and add > optional initialisation (you can have a look at other drivers, there are > already appropriate fields in the config structures for uart > configuration), or rely on Linux to hand it over initialised. > > Ralf > > > > > Thanks a lot for your help in advance! > > > > Kind regards. > > > > Stefano > > > > -- > > You received this message because you are subscribed to the Google > > Groups "Jailhouse" group. > > To unsubscribe from this group and stop receiving emails from it, send > > an email to [email protected] > > <mailto:[email protected]>. > > To view this discussion on the web visit > > > https://groups.google.com/d/msgid/jailhouse-dev/dd1ffb4f-3c78-4a8d-9982-7b589e0f3754n%40googlegroups.com > > < > https://groups.google.com/d/msgid/jailhouse-dev/dd1ffb4f-3c78-4a8d-9982-7b589e0f3754n%40googlegroups.com?utm_medium=email&utm_source=footer > >. > -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/c2dffc36-35f4-43bf-8166-107f4fcae804n%40googlegroups.com.
