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by rst
Sat Mar 21, 2020 1:24 pm
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

zeoneo wrote:
Sat Mar 21, 2020 12:46 pm
Yes, he is very experienced in this.

@9Pi thanks again :)

Yes, we have to thank him very much!
by rst
Sat Mar 21, 2020 12:42 pm
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

@zeoneo You're welcome. In the meantime my driver can associate and authenticate to a WPA2 enabled network. I have some issues, but it is working using the method to take the Plan 9 driver as it is (with some slight modifications) and build an environment around. I have to say, that the author of th...
by rst
Wed Mar 18, 2020 8:25 pm
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

i am confused with a memory-problem, somehow delete / free doesn't give back the with new / malloc allocated memory.... probably i am doing something wrong :-/ Hi styro, the value returned by m_Memory.GetHeapFreeSpace() is the free space, which has not been used for memory allocation at all before....
by rst
Sun Mar 15, 2020 4:49 pm
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

I was able to compile wifi /sample after toolchain upgrade but it does not send any uart response after booting. I have enable_uart=1 and core_freq=250Mhz hard coded in config.txt Even after commenting that it didn't work. I compiled fot RASPI 3 32 bit The sample program needs a HDMI display by def...
by rst
Sat Mar 14, 2020 7:22 pm
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

@zeoneo Quicker than expected I could push the development sources of the ported Plan 9 Wi-Fi driver to the wifi branch in the Circle repo. Please read this issue for details.
by rst
Sat Mar 14, 2020 10:24 am
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

zeoneo wrote:
Sat Mar 14, 2020 10:08 am
Is this effort open source? It will be great help to compile and play with plan9 drivers

I will push the source code to a branch in the Circle repo in a few days. I have to clean-up the code a bit before. I will give a notice here, when it is done.
by rst
Sat Mar 14, 2020 10:04 am
Forum: Bare metal, Assembly language
Topic: Bare metal BCM43438 Driver
Replies: 75
Views: 8947

Re: Bare metal BCM43438 Driver

FYI The Plan 9 ether4330.c and emmc.c drivers are working well on the RPi 3B, 3B+ and 4B with only slight modifications. I have built an emulation framework for the Plan 9 kernel environment with Circle and these drivers run successfully in it: logger: Circle 41.2 started on Raspberry Pi 3 Model B+ ...
by rst
Mon Mar 02, 2020 9:44 pm
Forum: Bare metal, Assembly language
Topic: Multi-core memory access scheduling/arbitration
Replies: 6
Views: 492

Re: Multi-core memory access scheduling/arbitration

That's excellent news, sounds like I can crack on with my project unhindered for the moment :) . I wasn't 100% on whether the mmu needed to be setup to arbitrate access, or something else entirely. Where do spin-locks come into it then? (If you find yourself with a moment to spare, lol). Spin-locks...
by rst
Mon Mar 02, 2020 7:21 pm
Forum: Bare metal, Assembly language
Topic: Multi-core memory access scheduling/arbitration
Replies: 6
Views: 492

Re: Multi-core memory access scheduling/arbitration

I have a linker script which has the entry point '_start' defined. It's my understanding based on what I've read online that ALL cores will enter at the entry point '_start' in start.S. Is this correct? It depends. Your understanding is right, if "kernel_old=1" is defined in "config.txt". Otherwise...
by rst
Wed Feb 26, 2020 6:57 pm
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

@blippy Thanks. I heard of rump kernels for the first time now. I did some quick reading. The concept is interesting, but I'm not sure, if there is still much activity in this project?
by rst
Wed Feb 26, 2020 4:12 pm
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

@rst. I'm trying out sample/15-files on real hardware. It reports Partition not found: usmd1-1 :( I'm just trying to access the first partition (i.e. VFAT) on the SD card. This sample works with USB mass-storage devices (e.g. flash drives) only. For SD card access have a look on addon/SDCard or add...
by rst
Wed Feb 26, 2020 7:02 am
Forum: Bare metal, Assembly language
Topic: CircleOS + BASIC
Replies: 6
Views: 703

Re: CircleOS + BASIC

That's a cool project. I started with BASIC too and went over to Z80 assembler then to understand, what is really going on. I think, BASIC is easy understandable for beginners and still of professional importance with Visual Basic .NET. You could use Git submodules for integrating other projects int...
by rst
Wed Feb 26, 2020 7:00 am
Forum: Bare metal, Assembly language
Topic: Understanding the CNTFRQ in Pi2 System timer
Replies: 5
Views: 401

Re: Understanding the CNTFRQ in Pi2 System timer

How could I use that value to create an interrupt every 2 seconds? You need the following Generic Timer registers: CNTPCT: Reading this 64-bit register returns the current value of the physical counter. You have to read it, add 2000000 to the value and write it to the next register. CNTP_CVAL: This...
by rst
Mon Feb 24, 2020 8:34 pm
Forum: Bare metal, Assembly language
Topic: Understanding the CNTFRQ in Pi2 System timer
Replies: 5
Views: 401

Re: Understanding the CNTFRQ in Pi2 System timer

This value is initialized by the ARM stub here . This stub is executed after ARM reset and before the loaded kernel image gets control, if "kernel_old=1" is _not_ defined in config.txt, which is the normal case. You do not need to write this register and cannot do it, because it is read-only after t...
by rst
Mon Feb 24, 2020 8:51 am
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

You should be able to use a cross toolchain from here on your Ubuntu. It only needs to be downloaded and extracted (no further install). Take the AArch32 bare-metal target (arm-none-eabi). The executables are in the bin/ subdirectory after extraction, which should be added to your PATH environment v...
by rst
Sun Feb 23, 2020 9:41 pm
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

Update : scratch that! I managed to get a build from my Ubuntu box. qemu-system-arm now launches my image. And it works! Cool. I have some interesting ideas what to do with circle. Great! Unfortunately this QEMU fork is relatively old and does not build on some platforms. But it's the only one I kn...
by rst
Sun Feb 23, 2020 4:54 pm
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 266
Views: 77513

Re: Circle - C++ bare metal environment (with USB)

@blippy For 32-bit operation I'm still using a slightly patched version of Andrew Baumann's QEMU fork for the RPi 2, which has USB support and provides the system timer, which is needed by Circle in 32-bit mode: https://github.com/rsta2/qemu You should add the following line before building the Circ...
by rst
Sun Feb 23, 2020 3:34 pm
Forum: Bare metal, Assembly language
Topic: Bare Metal Assembly
Replies: 2
Views: 318

Re: Bare Metal Assembly

The BCM2835 Manual said GPIO controller in VideoCore Virtual Address is 0x7E200000 and in ARM Physical Address is 0x20200000 I have been searched about this article, and I saw someone said "It's chosen by context." But what is context? What can 0x7E200000 do, and can I access it by ARM? 0x7E200000 ...
by rst
Sat Feb 22, 2020 4:54 pm
Forum: Bare metal, Assembly language
Topic: Problem booting PI3 in 64bit mode from 0x00 address
Replies: 4
Views: 388

Re: Problem booting PI3 in 64bit mode from 0x00 address

I looked for your code, I assume you mean this example? https://github.com/bztsrc/raspi3-tutorial/blob/master/14_raspbootin64/uart.c In here you seem to set the clock to a slower speed 4MHz. Is this clock only used by the UART0? That's why you can safely set it? You have to ask @bzt about this code...
by rst
Sat Feb 22, 2020 3:54 pm
Forum: Bare metal, Assembly language
Topic: Problem booting PI3 in 64bit mode from 0x00 address
Replies: 4
Views: 388

Re: Problem booting PI3 in 64bit mode from 0x00 address

My code use the Mini UART so I thought maybe the clock that feeds the Mini UART changed? Anyone know if this is true? Yes, it's true. I was facing a similar problem with Dwelch67's bootloader and it turned out, that the core clock frequency has changed. I cannot tell you the actual value, because I...
by rst
Sat Feb 22, 2020 3:44 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2C slave on Raspberry Pi 4 Model B?
Replies: 8
Views: 397

Re: I2C slave on Raspberry Pi 4 Model B?

Slave I2C seems to work as before. I'll check slave SPI at some stage, perhaps that has started to work (it doesn't work on earlier Pi models). So my problem is solved. Thank you too! Yes, it's interesting, if the SPI slave can be used now. I tried to implement a driver for it, but I didn't get it ...
by rst
Sat Feb 22, 2020 4:26 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2C slave on Raspberry Pi 4 Model B?
Replies: 8
Views: 397

Re: I2C slave on Raspberry Pi 4 Model B?

adun wrote:
Sat Feb 22, 2020 1:54 am
According to elinux
GPIO 8-11 is indeed for the I2C/SPI slave function on the RPi4.
GPIO 10: I2C_Slave_SDA
GPIO 11: I2C_Slave_SCL

I can confirm this working. Thank you!
by rst
Fri Feb 21, 2020 10:44 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2C slave on Raspberry Pi 4 Model B?
Replies: 8
Views: 397

Re: I2C slave on Raspberry Pi 4 Model B?

Okay. Thanks.
by rst
Fri Feb 21, 2020 9:51 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2C slave on Raspberry Pi 4 Model B?
Replies: 8
Views: 397

Re: I2C slave on Raspberry Pi 4 Model B?

joan wrote:
Fri Feb 21, 2020 8:57 pm
Does your driver work with the earlier Pi models?

Yes, I just tested it on a RPi 3 B+ again and it works.

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