PIC, IRQs and IDT?

[bubach]

That would be very nice!
I am getting nuts, while trying to figure out all bad C exampels were the source is spread in atleast 10 diffrent source files, are using structs and "hard-to-read"-ggc inline assembly.

/ Christoffer Bubach

[ASHLEY4]

Hi Christoffer, you can down load the idt demo from the my site
http://www.falconrybells.co.uk/
It's called "DemoVesa.zip" , let me know when you got it, or need more help.
ps: Are you still interested in developing a ASM OS with me ,if so let me know.

\\\\||////
(@@)
ASHLEY4.

[bubach]

Thank you!
Of couse i was trying to send you a PM.. >:(
But now i guess that my message to you goes public:

I am still intrested in helping you out.
I have been unactive for the past 6 months, so i had totally forgot about you and your OS. ;D

Do you have PHP and mySQL support on your server? Otherwise i can use my own webspace. I was thinking of setting up a "admin" site for the two of us, were we could send messages and share source-code.

After i have made that page, i will be as active as i can. Becasue i am still going to continue on my own OS. And i have to study aswell.

Any functions that you would like the page to have? (besides PM and source uploading?)
Address would be like http://bubach.1go.dk/DEX/

/ Christoffer

[ASHLEY4]

Y not join here: http://board.flatassembler.net/
Fasm is a great assembler, and there's lot's of help and there's a "OS Construction" forum, also has PM, and uploading and OS compo.
Also have a look here: http://512.decard.net/?body=intro

ps: There are so many highs and lows, with OS dev you need a break () .

\\\\||////
(@@)
ASHLEY4.

[bubach]

Now i am getting this: :'(

Code: Select all

00000004256i[BIOS ]  rombios.c,v 1.85.2.1 2003/01/16 21:58:42 cbothamy Exp $
00000318073i[KBD  ] reset-disable command received
00000475236e[HD   ] device set to 0 which does not exist
00000475529e[HD   ] device set to 1 which does not exist
00000607088i[CPU  ] BxError: instruction with op1=0xff
00000607088i[CPU  ] nnn was 7
00000607088i[CPU  ] WARNING: Encountered an unknown instruction (signalling illegal instruction):
00000607122e[CPU  ] load_seg_reg: LDT invalid
00000607220p[CPU  ] >>PANIC<< jump_protected: cs == 0
00000607220i[SYS  ] Last time is 1095436212
00000607220i[CPU  ] protected mode
00000607220i[CPU  ] CS.d_b = 32 bit
00000607220i[CPU  ] SS.d_b = 32 bit
00000607220i[CPU  ] | EAX=408716ea  EBX=00002443  ECX=00002820  EDX=0000051c
00000607220i[CPU  ] | ESP=0000ffa7  EBP=01f90002  ESI=0010006c  EDI=00000517
00000607220i[CPU  ] | IOPL=0 NV UP DI NG NZ AC PO CY
00000607220i[CPU  ] | SEG selector     base    limit G D
00000607220i[CPU  ] | SEG sltr(index|ti|rpl)     base    limit G D
00000607220i[CPU  ] |  DS:0010( 0002| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] |  ES:0010( 0002| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] |  FS:0010( 0002| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] |  GS:0010( 0002| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] |  SS:0010( 0002| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] |  CS:0008( 0001| 0|  0) 00000000 000fffff 1 1
00000607220i[CPU  ] | EIP=000006fd (000006f6)
00000607220i[CPU  ] | CR0=0x60000011 CR1=0x00000000 CR2=0x00000000
00000607220i[CPU  ] | CR3=0x00000000 CR4=0x00000000
00000607220i[     ] restoring default signal behavior
00000607220i[CTRL ] quit_sim called with exit code 1



========================================================================
Event type: PANIC
Device: [CPU  ]
Message: jump_protected: cs == 0

A PANIC has occurred.  Do you want to:
  cont       - continue execution
  alwayscont - continue execution, and don't ask again.
               This affects only PANIC events from device [CPU  ]
  die        - stop execution now
  abort      - dump core
Choose one of the actions above: [die]

So i tried to set cs, but it doesn?t help.
it says "load_seg_reg: LDT invalid"!!
here?s my idt (almost the same as yours), but i don?t have 256 desc. only 50. it should work anyway right?

/ Christoffer (at the ege of madness)

[Candy]

What number of segment are you trying to load? Do you use a number ending between 0 and 3, or between 8 and B?

[ASHLEY4]

Did you make shore it had the right start and end lable ?
I also need to see your code.

\\\\||////
(@@)
ASHLEY4.

[bubach]

opps, i forgot to attach the code.
i am using 0x08...

the idt-file:

Code: Select all

; Interrupt Description Table.
;------------------------------
idt_start:

     ; 0. Interrupt 0x00.
     ;---------------------
          dw isr00
          dw 0x08
          db 0
          db 0x8E
          dw 0

.......... ; a lot more that looks the same..

     ; 50. Interrupt 0x32.
     ;---------------------
          dw isr32   ; <- my own test int
          dw 0x08
          db 0
          db 0x8E
          dw 0


idt_end:

; IDT pointer.
;-------------------------
idt_pointer:
          dw idt_end - idt_start - 1
          dd idt_start

and a typical isr:

Code: Select all

; Unhandled Interrupt
;---------------------
          u_isr_str        db   "Unhandled Interrupt!", 0x00
u_isr:
          pushad
          push    es
          mov     ax, 0x10
          mov     es, ax

          mov     dl, 0x0A                            ; row, 00h -> 18h (0 -> 24)
          mov     dh, 0x20                            ; col, 00h -> 4Fh (0 -> 79)
          call    setcursorxy                         ; move it

          mov     esi, u_isr_str
          mov     al, 0x40                            ; Red.
          call    print

          cli
          hlt

          pop   es
          popad
          iret

from kernel.asm

Code: Select all

     ; Setup IDT.
     ;--------------
          lidt    [idt_pointer]                       ; Load interrupt description table

and finally the whole source as a zip.

thanks for all the help!

/ Christoffer

[Candy]

00000607088i[CPU ] WARNING: Encountered an unknown instruction (signalling illegal instruction):
00000607122e[CPU ] load_seg_reg: LDT invalid
00000607220p[CPU ] >>PANIC<< jump_protected: cs == 0

My result from this is that at 607088 you got an invalid instruction. Find out what it is.

Assuming it's intentional (UD2 or something, testing the IDT) you got an invalid segment load at 607122. This loads a segment with an invalid value. I am assuming this is in the illegal opcode handler.

At 607220 (100 cycles later), you get a CS load. Seeing the time distance, is this a task switch or something? You might have made a stack mistake somewhere. That would also explain the LDT load and if you don't use paging the invalid opcode too.

Check where it goes wrong (skip say 606900 cycles (s 606900) and then trace-on) and dump that here (as attachment). That'd probably help so much in getting the problem identified.

[bubach]

the probelm is that i haven?t really got the hang of bochs debugger.. ::)

i did notice that thing about a invalid instruction, but i can?t figure out where.
does nasm allow me to do invalid instructions? >:(

should i "reload" the (a new and improved) gdt in my kernel?
all that stuff is made in my loader.asm (including stack stuff.)

/ Christoffer

[beyondsociety]

Code: Select all

; 0. Interrupt 0x00.
    ;---------------------
          dw isr00
          dw 0x08
          db 0
          db 0x8E
          dw 0

0x08 = the code selector used to jump into protected mode.
It should be 0x10 = data selector as your referring data from your idt.

Hope this helps.

[bubach]

i think that i already have tested that, but thanks.
i can check it again.

/ Christoffer

[beyondsociety]

i think that i already have tested that, but thanks.
i can check it again.

You shouldnt have to re-check it as it should be the code selector (0x08). Staying up too late and working on other projects, causes you to give the wrong information. ;D

[bubach]

I fixed it. Thanks to you all...

/ Christoffer

[ASHLEY4]

bubach, what was the problem ?.

\\\\||////
(@@)
ASHLEY4.