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by Ultibo
Thu Jan 31, 2019 1:33 am
Forum: Bare metal, Assembly language
Topic: Updated revision information for CM3+
Replies: 3
Views: 250

Re: Updated revision information for CM3+

Excellent, thank you!
by Ultibo
Tue Jan 29, 2019 11:29 pm
Forum: Bare metal, Assembly language
Topic: Updated revision information for CM3+
Replies: 3
Views: 250

Updated revision information for CM3+

Hi, Just a prompt for someone with the relevant information available (James ?) to update the Revision codes page on GitHub with the latest information for the new CM3+ Assuming that everything else can be determined from the schematic and the device tree data, the revision code should be all that i...
by Ultibo
Sun Jan 20, 2019 10:56 pm
Forum: Bare metal, Assembly language
Topic: run from 0x00800000 (pi zero w)
Replies: 6
Views: 958

Re: run from 0x00800000 (pi zero w)

Mods this probably need to move to a linux forum because clearly it requires linux to give execute permissions to the memory block he wants to run the code in which emil correctly notes above. Not sure how you reach the conclusion that this requires Linux, if you enable the MMU you can apply whatev...
by Ultibo
Thu Dec 20, 2018 9:30 am
Forum: Bare metal, Assembly language
Topic: Low voltage detection, read voltage level
Replies: 2
Views: 857

Re: Low voltage detection, read voltage level

Any idea on how to retrieve this in bare metal would be much appreciated. Hey Schnoogle, I'm not sure if the GPIO35 stuff is actually still valid, so far never found a way to make use of it for low voltage detection. The current way that Raspbian does it seems to be by using a fairly recent mailbox...
by Ultibo
Thu Dec 13, 2018 11:31 pm
Forum: Bare metal, Assembly language
Topic: CSUD - Chadderz's Simple USB Driver (Source)
Replies: 56
Views: 15905

Re: CSUD - Chadderz's Simple USB Driver (Source)

I already have used interrupts. There are ever a register to enable, to disable, to know the source and to clear the irq pending. Searching BCM2837 datasheet I could not find any register to clear USB interrupt. Is there any one? Tks The documentation for the USB host in the Pi has never been made ...
by Ultibo
Wed Dec 12, 2018 12:24 am
Forum: Bare metal, Assembly language
Topic: Pi 3B+ Activity LED
Replies: 23
Views: 6635

Re: Pi 3B+ Activity LED

Did they change it from pin 29 to something else? bits 9,10,11 are gpio 23 and my other code would need to change to 23 as well... No, there has been no change. Even the new 3A+ is still pin 29 so your code is correct. What am I not understanding? I think someone is confusing GPSET/GPCLR which are ...
by Ultibo
Wed Nov 14, 2018 10:52 pm
Forum: Bare metal, Assembly language
Topic: information of bcm2835 mailbox and doorbell
Replies: 6
Views: 1714

Re: information of bcm2835 mailbox and doorbell

If I want to clear the doorbell interrupt and get the message from VideoCore, I need to read it in VCHIQ_DOORBELL_BELL0(0x3f00b840). If I want to send the message to VideoCore, I need to write the message to VCHIQ_DOORBELL_BELL2(0x3f00b848). Is this right? Yes that's correct but only in the context...
by Ultibo
Sat Nov 10, 2018 10:57 pm
Forum: Bare metal, Assembly language
Topic: information of bcm2835 mailbox and doorbell
Replies: 6
Views: 1714

Re: information of bcm2835 mailbox and doorbell

But I could not find any useful information about the bcm2835-doorbell in its documentations: https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2835/BCM2835-ARM-Peripherals.pdf https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2836/QA7_rev3.4.pdf After the test, I fo...
by Ultibo
Wed Sep 12, 2018 11:47 pm
Forum: Bare metal, Assembly language
Topic: Taking exception 3 [Prefetch Abort]
Replies: 12
Views: 3464

Re: Taking exception 3 [Prefetch Abort]

I figured out the exception occurs in the mmu_init function with the last call setting the sctlr_el1 register.I believe the memory to all be readable and executable so I'm not sure what the problem is. If the exception happens immediately after enabling the MMU it would tend to indicate that someth...
by Ultibo
Tue Sep 11, 2018 11:50 pm
Forum: Bare metal, Assembly language
Topic: Taking exception 3 [Prefetch Abort]
Replies: 12
Views: 3464

Re: Taking exception 3 [Prefetch Abort]

I would like to find this bug myself so the information may be a bit vague ask for clarification if it is needed. Yes, the only way to truly understand what is happening is to work it out yourself, no matter how painful and tedious that may be ;). I'm not sure yet exactly what this error means but ...
by Ultibo
Sun Sep 09, 2018 11:26 pm
Forum: Bare metal, Assembly language
Topic: Reasons behind MMIO base address
Replies: 3
Views: 737

Re: Reasons behind MMIO base address

I am curious as to why they didn't just start the MMIO at 0x40000000? What we have learned from snippets of information provided over the years is that the VC4 GPU only supports a 1GB address space (which is the reason why the Pi cannot have more than 1GB) and because the GPU needs access to the pe...
by Ultibo
Wed Aug 29, 2018 10:10 am
Forum: Bare metal, Assembly language
Topic: Multiple GPU hardware layers?
Replies: 4
Views: 1078

Re: Multiple GPU hardware layers?

I know we can request 1 frame buffer at various virtual sizes through the mailbox interface, but is there a way to get multiple hardware layers from the GPU? With hardware layers I mean multiple frame buffers displayed by the GPU on top of each other with alpha transparency. The interface you are a...
by Ultibo
Mon Aug 13, 2018 11:37 am
Forum: Bare metal, Assembly language
Topic: Xinu release
Replies: 21
Views: 3514

Re: Xinu release

LizardLad_1 wrote:
Sat Aug 11, 2018 4:19 am
Are you going to release the code on GitHub or GitLab?
Maybe neither, it seems the original authors of Xinu already have.

http://reu.mscs.mu.edu/index.php/Upgrad ... berry_Pi_3
https://dl.acm.org/citation.cfm?id=3162 ... CM&coll=DL




.
by Ultibo
Tue Jun 19, 2018 12:34 am
Forum: Bare metal, Assembly language
Topic: Raspberry Pi 3B+ Bare Metal USB Driver
Replies: 41
Views: 4166

Re: Raspberry Pi 3B+ Bare Metal USB Driver

I also noticed one more thing. After waiting a few minutes for all the devices to be attached, it shows that there are 2 LAN7515 hubs... 1 = roothub 2 = LAN hub 3 = is also LAN hub..?? 4 = ethernet device 5 = mouse Hi rlatinov, The Pi3B+ has two hubs built into the LAN7515 device, this is normal an...
by Ultibo
Tue Jun 12, 2018 4:54 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: [Partly-Solved] VCHIQ/MMAL Camera access

But to answer your question, there is no specific initialization for the spinlock/mutex necessary to be called before they can be used. Alas, the particular case I was thinking of only applies if your lock structures (spin/mutex) require initialization before use. VCHIQ just did not respond to the ...
by Ultibo
Sun Jun 10, 2018 11:48 pm
Forum: Bare metal, Assembly language
Topic: Baking Pi issues
Replies: 8
Views: 1261

Re: Baking Pi issues

I just got a Raspberry Pi 3 B+ and wanted to do the Baking Pi tutorial http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/ok01.html After having some issues i discovered this thread https://www.raspberrypi.org/forums/viewtopic.php?t=82871 and did exactly the same but it doesnt work for me. I...
by Ultibo
Fri Jun 08, 2018 12:09 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: [Partly-Solved] VCHIQ/MMAL Camera access

This would usually trigger the VCHIQ callback which is forwarded into MMAL with reason VCHIQ_MESSAGE_AVAILABLE that does check the returned messageID to be MMAL_WORKER_BUFFER_TO_HOST and than triggers the VCHIQ_BULK_RECIEVE. But this initial callback from VCHIQ, once the buffer has been passed is n...
by Ultibo
Mon Jun 04, 2018 2:27 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: [Partly-Solved] VCHIQ/MMAL Camera access

Hey Schnoogle, I've the MMU setup with L1 caching active. I've no clue how to get L2 caches setup but the disable_l2cache switch in the confog.txt should deactivate it in GPU anyway if I understood it correct. Based on that I'd suggest that the disable_l2cache/enable_l2cache setting is at best irrel...
by Ultibo
Sun Jun 03, 2018 1:07 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: [Partly-Solved] VCHIQ/MMAL Camera access

Hi again Schnoogle, So close and yet so far! I just retested the values with our implementation, we can happily capture a 3280 x 2464 image from the camera so your 128 x 128 should be easily within limits. I can also confirm that to use the camera you must have start_x.elf (and fixup_x.dat) with the...
by Ultibo
Tue May 22, 2018 10:43 am
Forum: General discussion
Topic: Multiple framebuffer support - testers wanted
Replies: 10
Views: 938

Re: Multiple framebuffer support - testers wanted

Would anyone be interesting in beta testing? You will need to build your own kernel and modules, and be able to install them on an SD card. There will also be a new firmware (start*.elf) required. You can already see the kernel changes in this branch on my github https://github.com/JamesH65/linux/t...
by Ultibo
Tue May 15, 2018 12:12 am
Forum: Bare metal, Assembly language
Topic: Is there any way to emulate timer interrupt in qemu?
Replies: 8
Views: 2304

Re: Is there any way to emulate timer interrupt in qemu?

I've tested the system timer (whose base address is 0x3f003000) and the local timer (whose base is 0x3f00b000). They can work on my pi3, but it seems that none of them are emulated in qemu (I use qemu 2.12, which supports -M raspi3). Can we emulate timer interrupts in qemu? Thanks. Looking at the Q...
by Ultibo
Sun May 13, 2018 11:21 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: VCHIQ/MMAL Camera access

You are welcome Schnoogle, please let us know how you go.

PS. We are from Australia so cold beer is good!!
by Ultibo
Sun May 13, 2018 1:14 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: VCHIQ/MMAL Camera access

I'm developing under windows so UART console is my friend as QEMU does not work on Windows for real debugging as far as I know and I guess VCHIQ might not be properly emulated there as well.... When doing bare metal the UART is always your friend ;) I think it could be a very long time before there...
by Ultibo
Sat May 12, 2018 1:46 am
Forum: Bare metal, Assembly language
Topic: [Partly-Solved] VCHIQ/MMAL Camera access
Replies: 28
Views: 2778

Re: VCHIQ/MMAL Camera access

Hi BR Schnoogle, Sounds like you are close to getting it working if you have got that far. Without any other information it is hard to offer much advice but I can tell you that both bulk transmit and receive work in the Ultibo port of VCHIQ, data is able to be received from the camera and we have wo...
by Ultibo
Tue May 08, 2018 3:28 am
Forum: Bare metal, Assembly language
Topic: Correct value for cntfrq_el0 in Pi 3 B+
Replies: 2
Views: 498

Re: Correct value for cntfrq_el0 in Pi 3 B+

AntonioND wrote:
Mon May 07, 2018 6:09 pm
I was wondering if the frequency of the oscillator has changed between Pi 3 B and Pi 3 B+.
No changes, the frequency of the oscillator is still 19.2MHz as per the previous models.

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