juj

Thanks for the comment. It is appreciated, however many of the statements about refresh rate there are incorrect, or perhaps apply to your specific case. E.g. SPI can well run...

Again, please let's not derail what is already becoming a very lengthy thread with unrelated conversation. Feel free to open a followup at e.g. [fbcp-ili9341 tracker](https://github.com/juj/fbcp-ili9341/issues), Raspberry Pi [Interfacing (DSI,...

I worked around this by setting the pref `xpinstall.signatures.required` to `false`. However it seems that the pref automatically turns itself back on after a while (or even on next restart?)....

Oh, now after a while, the hang resolved in a dialog ``` Could not understand response from symbolication server at http://symbolapi.mozilla.org/gecko-profiler/ Please consider filing a bug at https://bugzilla.mozilla.org/ ```

> For any future reader: > To get this example working on a Raspberry Pi 2 B i had to replace this function: > > uintptr_t virtToUncachedPhys(void *virt, int pagemapfd)...

> Sorry for misguiding you. Oh no harm at all! I actually was poking on the same before having read this bug report, and ended up investigating the same thing,...

Reducing the test case further, https://github.com/juj/Raspberry-Pi-DMA-Example/commit/4dd506b09f133a5828d2e2d41de55f631c4e0769 has an example that does an allocation of a single page, and then tries to create an uncached view to the page, and memset...

Playing around, changing [this line](https://github.com/juj/Raspberry-Pi-DMA-Example/commit/4dd506b09f133a5828d2e2d41de55f631c4e0769#diff-defc2be189f053f31f0ac4c5a40cad2cR42) from ```c++ return virtToPhys(virt, pagemapfd) | 0x40000000; ``` to ```c++ return virtToPhys(virt, pagemapfd); ``` i.e. not taking the physical page over to uncached address range,...

> @juj It looks to me like you've confirmed issue #2 for the RPi 3. Thanks for posting that, commented there about what I've found out so far. > In...

Utilizing the mailbox interface, I was able to get DMA now working. The code I ended up with reads as ```c++ struct GpuMemory { uint32_t allocationHandle; void *virtualAddr; uintptr_t busAddress;...