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by Cycl0ne
Sat Aug 04, 2012 5:16 pm
Forum: Bare metal, Assembly language
Topic: dual boot understanding
Replies: 20
Views: 12268

Re: dual boot understanding

http://www.denx.de/wiki/U-Boot/

denx is the company behind u-boot.

if you think in a pc world, U-Boot = Grub Bootloader.
Other systems as x86 normaly dont have a bios and then you "burn" U-Boot into a ROM for bootup. Nearly the same as EFI for Macs.
by Cycl0ne
Sat Aug 04, 2012 5:10 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

Not true. hmm as mentionend in another post: broadcom doc says: 128bit/32bit the other 8bit mode is not documented. and 8bit alignment: = 7pixel offset in 32 bpp or? since the last 3 bits are 0 of the adress. if my framebuffer starts at: 0x0 and i want to put something at position 1,1 to 10,10 = st...
by Cycl0ne
Sat Aug 04, 2012 5:06 pm
Forum: Bare metal, Assembly language
Topic: FB doublebuffering
Replies: 27
Views: 6586

Re: FB doublebuffering

just put the y_offset into your init message. and when you want to switch, just send a new message with: set offset_y
by Cycl0ne
Sat Aug 04, 2012 5:04 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

Dsiadvantage of DMA: all transfer has to be 128bit aligned. so Blitting/Moving/filling gfx on screen will let your operations miss 127 pixels ;) in 32/24bpp mode. lower bpp worser. Well i have not even looked at DMA for the PI, but i know someone that's making bare metal GBA emulator and he uses DM...
by Cycl0ne
Sat Aug 04, 2012 5:00 pm
Forum: Bare metal, Assembly language
Topic: Bare Metal VideoCore
Replies: 27
Views: 14127

Re: Bare Metal VideoCore

I 100% agree with this bit that romell wrote. Yes its possible to reverse engineered anything, give time and knowledge. But whether you do it, is down to two things. 1. Do i need that info, which in this case i do not. 2. Does Broadcom given me enough info to do my job and the answer is yes. So goo...
by Cycl0ne
Sat Aug 04, 2012 4:06 pm
Forum: Bare metal, Assembly language
Topic: dual boot understanding
Replies: 20
Views: 12268

Re: dual boot understanding

After a lot of searching I came across two projects: 1. berryboot - but I guess it simply provides switching to different distributions but loads the same berryboot kernel always so my thinking is that it won't serve my purpose to use it to dual boot between raspbmc (which probably require 128/128 ...
by Cycl0ne
Sat Aug 04, 2012 3:40 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

Dsiadvantage of DMA: all transfer has to be 128bit aligned. so Blitting/Moving/filling gfx on screen will let your operations miss 127 pixels ;) in 32/24bpp mode. lower bpp worser.
by Cycl0ne
Sat Aug 04, 2012 10:04 am
Forum: Bare metal, Assembly language
Topic: dual boot understanding
Replies: 20
Views: 12268

Re: dual boot understanding

Hi, all is not possible. The Ram Config has to be compiled, so no boot switching. UBoot is a native bootloader yes, but not for raspberry pi. it loads after teh start.elf, as everybody else. to make things short: on a pc you cant "switch" between bioses. see the start.elf as the bios of the raspberr...
by Cycl0ne
Sat Aug 04, 2012 3:05 am
Forum: Bare metal, Assembly language
Topic: Bare Metal VideoCore
Replies: 27
Views: 14127

Re: Bare Metal VideoCore

Hi,

nice. But I wouldnt go so far by disassm the core. It would be enough if one would disasm the following file "libbcm_host.so" where all the commands are sitting for talking to the mailbox, this documented, would give us a real start.

Cheers.
by Cycl0ne
Fri Aug 03, 2012 11:35 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

As to why your code's disappearing, I don't know. Are you using gcc to assemble and link in one step? I found the "fault" thanks to valtonia. :) As thought the O1-O3 optimizer finds this static jumptable/romtag of mine which is not used directly. this he optimizes away and the functions cant be use...
by Cycl0ne
Fri Aug 03, 2012 11:00 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

Ah, -O0 is going to (and has done) produce some really braindead code. It's fine for debugging, but there's no way you can use it in production. Rather than taking your loop variable into a register, for example, it stores it in the stack frame, and pulls it out every time it needs to update it, fo...
by Cycl0ne
Fri Aug 03, 2012 10:07 pm
Forum: Bare metal, Assembly language
Topic: [Guide] Beginning Bare Metal on Raspi
Replies: 38
Views: 34579

Re: [Guide] Beginning Bare Metal on Raspi

just create a file calles: "dontdeletethis" and bin will be in your repo ;)
by Cycl0ne
Fri Aug 03, 2012 10:05 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

My code gets to disappear, because im using jumptables for the access: static APTR FuncTab[] = { (void(*)) gfx_SetMode, (void(*)) gfx_SetFillMode, (void(*)) gfx_SetUseBackground, (void(*)) gfx_SetAPen, (void(*)) gfx_SetBPen, (void(*)) gfx_SetAPenC, (void(*)) gfx_SetBPenC, (void(*)) gfx_SetDash, (voi...
by Cycl0ne
Fri Aug 03, 2012 5:08 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

doesnt change anything in time:
Buffer Addr 49385000
Time: 495003 Hz
Time: 22085 Hz

But with my new Memset32(UINT32*, UINT32, UINT32);

I achieve: 22085 Hz.... I believe now we are done, no more speed records. 45FPS is ok at the moment until I get the hardware-acc. stuff from you dom ;-)
by Cycl0ne
Fri Aug 03, 2012 4:48 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

GCC: arm-none-eabi-gcc.exe (GNU Tools for ARM Embedded Processors) 4.6.2 20120316 (release) [ARM/embedded-4_6-branch revision 185452] Copyright (C) 2011 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or ...
by Cycl0ne
Fri Aug 03, 2012 12:13 pm
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Re: Framebuffer Speed

Ok made some Speedtest: 1sec = 1000000 Hz With this C Routine only one *buff++: Time: 1036010 Hz With 4 *buff++: Time: 573781 Hz With 8 *buff++: Time: 495534 Hz With assembler optimized MemSet from github: Time: 24829 Hz R-E-S-P-E-C-T. Dexos, we have to code in Assembler ;-) Its nearly 50times faste...
by Cycl0ne
Fri Aug 03, 2012 10:54 am
Forum: Bare metal, Assembly language
Topic: Mailbox property interface->Suggestions
Replies: 5
Views: 3324

Re: Mailbox property interface->Suggestions

Can you add some RectFill/BlitOperations to these Properties? DMA would be much less overhead (and as fast) for blits and fills. For blended ops, I'll think about it. But hasnt DMA the limitation of correct alignment of memory for that? will it be possible for the rectfill/blit to work on every BPP...
by Cycl0ne
Fri Aug 03, 2012 10:30 am
Forum: Bare metal, Assembly language
Topic: Framebuffer Speed
Replies: 18
Views: 8337

Framebuffer Speed

Hi, just wondering, if its true that it is so slow, or am i doing something wrong. I opened up the Framebuffer (old style like linux fb) and clear the screen white (resolution 1600x1200 in 32bit): DPrintF("Buffer Addr %x\n", bm->Addr); INT32 *buff = (INT32*)bm->Addr; for (int i= 0; i<1600*1200; i=+4...
by Cycl0ne
Fri Aug 03, 2012 8:17 am
Forum: Bare metal, Assembly language
Topic: Mailbox property interface->Suggestions
Replies: 5
Views: 3324

Re: Mailbox property interface->Suggestions

Ohh I forgot:

Hardware cursor would be nice too.
by Cycl0ne
Fri Aug 03, 2012 12:43 am
Forum: Bare metal, Assembly language
Topic: Mailbox property interface->Suggestions
Replies: 5
Views: 3324

Mailbox property interface->Suggestions

Hi, got some questions/featurerequest on this thing: Can you add some RectFill/BlitOperations to these Properties? And what about Interrupts? Can you make something like: i send a request to the mailbox and get a int back when its finished? And what about Doublebuffering or Offside Buffers? Thanks. ...
by Cycl0ne
Fri Aug 03, 2012 12:41 am
Forum: Deutsch
Topic: Jemand da? Vorstellungsrunde
Replies: 77
Views: 19881

Re: Jemand da? Vorstellungsrunde

Moin,

ich hab mein PI seit ca. 4 Wochen über Ebay, war nur 10€ teurer als RS (komplett mit Zubehör für 60€, das war fair (SDkarte, Netzteil, Gehäuse).

Mein Repo woran ich bastel:
https://github.com/cycl0ne/poweros_raspi

Finden tut ihr mich in der BareMetal Fraktion.

Cheers.
by Cycl0ne
Tue Jul 31, 2012 3:51 pm
Forum: Bare metal, Assembly language
Topic: Virtual memory and linking
Replies: 21
Views: 8587

Re: Virtual memory and linking

you have to get yourself some infos on OS Design. http://wiki.osdev.org is a good place to start. Linux, Windows, MacOSx, all compile their binaries (programms) to 0x0. so if you put your kernel at 0x0800, you have to write your own compiler/linker tools. Most 32 bit OS tend to use a 2:2 approach (2...
by Cycl0ne
Thu Jul 26, 2012 10:39 am
Forum: Bare metal, Assembly language
Topic: Use of UART0
Replies: 8
Views: 8761

Re: Use of UART0

Hmm wehre is UART0 and where is UART1 :-) Im just using the Dwelch config :lol:
by Cycl0ne
Wed Jul 25, 2012 7:15 pm
Forum: Bare metal, Assembly language
Topic: Some advanced C Questions
Replies: 18
Views: 5890

Re: Some advanced C Questions

If the target address of an STREX is different from the preceding LDREX in the same execution thread, behavior can be UNPREDICTABLE. As a result, an LDREX/STREX pair can only be relied upon to eventually succeed if they are executed with the same address. Where a context switch or exception might r...
by Cycl0ne
Wed Jul 25, 2012 6:06 am
Forum: Bare metal, Assembly language
Topic: [Guide] Beginning Bare Metal on Raspi
Replies: 38
Views: 34579

Re: [Guide] Beginning Bare Metal on Raspi

is it allowed to put them into a git repo? i could make a folder Docs and put them there, with the BCM Manual. And yes its an ARMv6.

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