Re: BUG: fb_imageblit called before fb_check_var and fb_set_par function

[Knut Petersen <Knut_Petersen@t-online.de>]

Hi Antonio,

> Perhaps, if you have the time, you can instrument it better so we can 
> pinpoint
> where this unwanted calls are coming from.  Months were spent trying 
> to fix this
> problem, mainly by BenH, and I don't want any stones left unturned. 

So lets conclude: The problem is _not_ fixed and still present in 
2.6.13-rc7.
I added BenH and Andrew Morton to the cc-list.

I added a printk at the start of redraw_screen() and a show_trace() in 
cyblafb_sync().

Imho
   - there is a bug of the trident driver in X that should _never_ 
disable mmio for
     the cyberblade core if it is started with mmio enabled.  A bug Alan 
Hourihane
     should fix.
  - there also is a serious kernel bug as no drawing function must be called
     prior to setting up the framebuffer driver by executing the 
set_par() call.

I´m happy to have learned enough about the low -level framebuffer layer,
but I´m definitely not qualified to do fixed in char/vt.c, 
char/vt_ioctl.c etc.

Read some shortened dmesg logs:
(cyblafb: Switching ... marks the start of the fb_set_par function)

==========
First log:
==========
1-init to runlevel 3
2-login as root on tty1
3-init 5
4-switching back to tty1 with ctrl-alt-f1

...
Detected 533.506 MHz processor.
Using tsc for high-res timesource
redraw_screen: called with is_switch 0 and vc->vc_mode 0
Console: colour dummy device 80x25
...
ACPI: Assume root bridge [\_SB_.PCI0] bus is 0
Boot video device is 0000:01:00.0
ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT]
...
cyblafb: CyblaFB version 0.53 initializing
ACPI: PCI Interrupt Link [LNKA] enabled at IRQ 11
PCI: setting IRQ 11 as level-triggered
ACPI: PCI Interrupt 0000:01:00.0[A] -> Link [LNKA] -> GSI 11 (level, 
low) -> IRQ 11
cyblafb: framebuffer size = 8192 Kb
cyblafb: detected startup mode: fbset -g 1280 1024 1280 ??? 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
cyblafb: Switching to new mode: fbset -g 1280 1024 1280 2662 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
redraw_screen: called with is_switch 0 and vc->vc_mode 0
Console: switching to colour frame buffer device 160x64
...
ACPI: PCI Interrupt 0000:00:11.5[C] -> Link [LNKC] -> GSI 12 (level, 
low) -> IRQ 12
PCI: Setting latency timer of device 0000:00:11.5 to 64
redraw_screen: called with is_switch 0 and vc->vc_mode 0
eth0: no IPv6 routers present
redraw_screen: called with is_switch 0 and vc->vc_mode 0
******** Now logged in as root on tty1
redraw_screen: called with is_switch 1 and vc->vc_mode 0
******** X has been started here, we are in xterm. Now ctrl-alt-f1:
redraw_screen: called with is_switch 1 and vc->vc_mode 0
cyblafb: Switching to new mode: fbset -g 1280 1024 1280 2662 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
******** We switched back to tty1

As you can see, redraw_screen is called prior to cyblafb_setpar, but 
nothing bad is
triggered because the X trident buffer does not disable mmio.
===========
Second log:
===========
1-init to runlevel 5
2-switching to tty1 with ctrl-alt-f1

...
Detected 533.508 MHz processor.
Using tsc for high-res timesource
redraw_screen: called with is_switch 0 and vc->vc_mode 0
Console: colour dummy device 80x25
...
ACPI: Assume root bridge [\_SB_.PCI0] bus is 0
Boot video device is 0000:01:00.0
ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT]
...
cyblafb: CyblaFB version 0.53 initializing
ACPI: PCI Interrupt Link [LNKA] enabled at IRQ 11
PCI: setting IRQ 11 as level-triggered
ACPI: PCI Interrupt 0000:01:00.0[A] -> Link [LNKA] -> GSI 11 (level, 
low) -> IRQ 11
cyblafb: framebuffer size = 8192 Kb
cyblafb: detected startup mode: fbset -g 1280 1024 1280 ??? 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
cyblafb: Switching to new mode: fbset -g 1280 1024 1280 2662 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
redraw_screen: called with is_switch 0 and vc->vc_mode 0
Console: switching to colour frame buffer device 160x64
...
ACPI: PCI Interrupt 0000:00:11.5[C] -> Link [LNKC] -> GSI 12 (level, 
low) -> IRQ 12
PCI: Setting latency timer of device 0000:00:11.5 to 64
redraw_screen: called with is_switch 0 and vc->vc_mode 0
eth0: no IPv6 routers present
redraw_screen: called with is_switch 1 and vc->vc_mode 0
******** X has been started here, we are in xterm
******** ctrl-alt-f1
redraw_screen: called with is_switch 1 and vc->vc_mode 0
cyblafb: GRAPHICS ENGINE TIMED OUT!
 [<c0246abd>] cyblafb_imageblit+0xad/0x230
 [<c0241a3b>] bit_putcs+0x2eb/0x560
 [<c01138a5>] __wake_up_common+0x35/0x70
 [<c023dba8>] fbcon_putcs+0x168/0x210
 [<c028c11b>] do_update_region+0x11b/0x180
 [<c028cc13>] redraw_screen+0x143/0x1e0
 [<c0288788>] complete_change_console+0x28/0xd0
 [<c0287cbd>] vt_ioctl+0x111d/0x1aa0
 [<c014886e>] __handle_mm_fault+0x13e/0x180
 [<c011174d>] do_page_fault+0x19d/0x550
 [<c03a7dd7>] schedule+0x337/0x670
 [<c0286ba0>] vt_ioctl+0x0/0x1aa0
 [<c0281fbc>] tty_ioctl+0x17c/0x410
 [<c011364a>] scheduler_tick+0x17a/0x310
 [<c0169d98>] do_ioctl+0x48/0x80
 [<c0169f2a>] vfs_ioctl+0x5a/0x1d0
 [<c016a0e6>] sys_ioctl+0x46/0x60
 [<c0102909>] syscall_call+0x7/0xb
cyblafb: Switching to new mode: fbset -g 1280 1024 1280 2662 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
******** Now logged in as root on tty1
redraw_screen: called with is_switch 1 and vc->vc_mode 1
******** switched to xterm
redraw_screen: called with is_switch 1 and vc->vc_mode 0
cyblafb: Switching to new mode: fbset -g 1280 1024 1280 2662 8 -t 7407 
232 16 39 0 160 3
redraw_screen: called with is_switch 0 and vc->vc_mode 0
******** switched back to tty1

cu,
 Knut



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