Hi, On 7/6/19 7:37 PM, Julien Grall wrote:
> > Yes it would be sensible to try to implement a crossbar driver in Xen > and test with the UART. Looking at the driver in Linux, this should not > be too difficult. I don't understand why xen doesn't react on triple Ctrl+a. It probably means that UART's interrupts doesn't work. But I was able to type in u-boot so the uart should be already configured. Or not? Should I set up it in a crossbar first? > >>> > > I don't think I ever suggested to not expose the crossbar to Dom0. > Instead, I suggested to virtualize for Dom0, so it can be used by Xen as > well. > >>> >>>> Also, the tegra >>>> implementation blacklist only a uart. >>> >>> I don't understand this. >> In here [1] you can find that only uart is blacklisted (in >> tegra_blacklist_dev[]). So, in tegra they didn't blacklist their version >> of the crossbar. > > This series has not been merged. In other word, the code is not yet > matching the expectations of the maintainers. > > I pointed you to this series, because I think some of the idea could be > re-used for implementing the crossbar. > > In this particular case, it has been suggested to use blacklist_dev > rather than unmapping (see [2]). > Hm, I thought that idea behind the patch was that they unmap the control register and intercept the calls from Linux to that control register. At the same time they preserved the crossbar in the device tree. And, I thought that you wanted to demonstrate this exact thing. Could you describe how in general the approach with blacklisting should work? -- Regards, Denis Obrezkov _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
