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by hartnett
Tue Mar 10, 2020 9:54 pm
Forum: Bare metal, Assembly language
Topic: RPi startup and RPi4 ?
Replies: 10
Views: 995

RPi startup and RPi4 ?

Hi, I've been on an RPi "hiatus" for quite a while. Then I saw the announcements about the RPi4B.. and I thought I would like to jump back in and give it a try. First some history/background.. I like to develop and experiment with bare metal operating systems. Mostly real-time operating systems infl...
by hartnett
Fri Apr 11, 2014 5:37 pm
Forum: Bare metal, Assembly language
Topic: CSUD question(s)...
Replies: 4
Views: 1545

Re: CSUD question(s)...

Thanks for the replies. Even with different sizes, I notice that the physical register values are NOT what I program them to be. I tried moving the FIFO size (receive, nonperiodicTransmit and periodicTransmit) and FIFO flushing to be AFTER the loops where he (CSUD) disables all the channels.. and no...
by hartnett
Thu Apr 10, 2014 6:12 pm
Forum: Bare metal, Assembly language
Topic: CSUD question(s)...
Replies: 4
Views: 1545

CSUD question(s)...

I'm experimenting with CSUD.. First, I see in the code (designware20.h) that ReceiveFifoSize = NonPeriodicFifoSize = PeriodicFifoSize = 20480. But doesn't the sume of those have to be less than Hardware.FifoDepth (= 4080)? And the code has ChannelCount = 16. I think (?) that should be 8. And I think...
by hartnett
Wed Apr 09, 2014 9:32 pm
Forum: Bare metal, Assembly language
Topic: Implementing a USB Driver
Replies: 86
Views: 22491

Re: Implementing a USB Driver

I have been messing around with the RPi DWC USB driver(s) - off and on - for a while now. This is a BARE METAL endeavor.. my "OS" just uses UART and TIMER interrupts. All my console I/O is to the UART. I'm running "them" (see below) on both the model A and model B RPi (and, if you're not familiar wi...
by hartnett
Fri Dec 13, 2013 6:43 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

Re: USB (DWC) Enumeration ?

Thanks Rene,

And, yes, I caught the error of my ways about a minute after I hit "submit." Nothing like replacing one bug with another.

Regards,

Tom
by hartnett
Wed Dec 11, 2013 7:53 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

Re: USB (DWC) Enumeration ?

Update.. I had (at least) two problems: (1) I was unable to enumerate certain devices, and (2) the DWC HCD enumerates the downstream port to the LAN9512 fine (High-Speed).. but the downstream ports for the LAN9512 "think" they're Full-Speed. I was using u-boot-pi-rpi, linux-rpi-3.6.y and csud_v0-1_s...
by hartnett
Wed Dec 04, 2013 8:15 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

Re: USB (DWC) Enumeration ?

Rene, Thanks. I know the maxPacketSize0 is - on one hand - "just a number" in my "root hub" DEVICE descriptor. But it also has to be physically "backed up" by the DWC's FIFOs and DMA controllers. Other implementations list very specific "endpoint 0" max packet sizes. For example, for the AT91SAM7X51...
by hartnett
Wed Dec 04, 2013 4:17 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

Re: USB (DWC) Enumeration ?

Rene, I understand that when the "root hub" is looking downstream to the LAN9512, it reads HPRT0 (offset 0x440) and specifically the PRTSPD bits (18:17), but when I'm trying to look at the LAN9512's downstream ports, I'm actually sending control packets downstream to the 9512 and, in effect, asking ...
by hartnett
Tue Dec 03, 2013 9:30 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

Re: USB (DWC) Enumeration ?

Rene, Thanks. But I am doing pretty much the same thing. When the BCM2835/DWC OTG HCD is enumerating the LAN9512 hub, the returned port status is 50x (i.e., high-speed). But then when the enumeration (recursively) drills down a level and I try to enumerate an (e.g.) USB 2.0 hub, the returned port st...
by hartnett
Wed Nov 27, 2013 8:57 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Enumeration ?
Replies: 11
Views: 8108

USB (DWC) Enumeration ?

I'm trying to get a USB stack going on a "bare metal" Pi (no operating system.. just a simple controller and command interpreter)... I started with u-boot-pi-rpi and consulted csud_v0-1_src as necessary. I'm able to initialize all the BCM2835/DWC hardware and get it to enumerate a handful of devices...
by hartnett
Fri Nov 22, 2013 7:40 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Initialization?
Replies: 4
Views: 2392

Re: USB (DWC) Initialization?

Rene,

Thanks 1e6! You made my week (maybe even more)! (Of course, this just means I can crawl. I'm sure walking (next) and running (later) will have their own difficulties.)

Thanks and regards,

Tom
by hartnett
Thu Nov 21, 2013 9:03 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Initialization?
Replies: 4
Views: 2392

Re: USB (DWC) Initialization?

Rene, Thanks for the reply. As part of the initialization, I'm writing 0 to the PCGCCTL (at 20980E00). Is the PCGCCTL different from the "power management mailbox"? If they are different, can you give me a pointer to where the mailbox is? And if not, why 80? It looks like the Linux and U-Boot code i...
by hartnett
Wed Nov 20, 2013 9:25 pm
Forum: Bare metal, Assembly language
Topic: USB (DWC) Initialization?
Replies: 4
Views: 2392

USB (DWC) Initialization?

Sorry if this is covering a lot of old ground, but... I've been playing around with trying to get the DWC OTG host controller running on a "bare metal" (i.e., no OS) system. I've looked at Linux (linux-rpi-3.6.y), U-Boot (u-boot-pi-rpi) and CSUD (csud_v0-1_src). I started with the U-Boot version (al...
by hartnett
Wed Nov 20, 2013 9:03 pm
Forum: Bare metal, Assembly language
Topic: [BareMetal] USB
Replies: 31
Views: 12409

Re: [BareMetal] USB

[quote="Cycl0ne"]Hi, thanks for all your help, my USB Stack is now working :) èñäñ() HANG! Soft Reset GRSTCTL=b108 Hi, I know this is "ancient history," but I noticed the "HANG! Soft Reset" in the trace (after the USB stack seems to be working). I've perused the code.. and even though dwc_otg_core_r...
by hartnett
Fri Mar 01, 2013 10:31 pm
Forum: Bare metal, Assembly language
Topic: PL011 UART & interrupts problem
Replies: 12
Views: 5489

Re: PL011 UART & interrupts problem

Thanks 1e6. Where did you find that?

Regards,

Tom
by hartnett
Fri Mar 01, 2013 9:25 pm
Forum: Bare metal, Assembly language
Topic: PL011 UART & interrupts problem
Replies: 12
Views: 5489

Re: PL011 UART & interrupts problem

I'm new to the RPi world, so forgive me if piggy-backing my question on this post was not the best path, but..
I'm trying use the UART (Ch. 13). What is the value for the "UART reference clock frequency" (a.k.a. FAURTCLK)?

Thanks and regards,

Tom

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