Re: framebuffer refresh rate and geometry
On Mon, 11 Apr 2022, Emmanuel Dreyfus wrote:
When the kernel initialize a framebuffer, the signal ouput changes a bit
fro mwhat is inherited from the BIOS. I face the situation where the
display looses the signal, and I suspect this is related to the refresh
rate.
OK, I'm able to get a usable UEFI console (intelfb) with the hack below
(starting X, however, immediately locks up the system):
```
diff -urN a/sys/external/bsd/drm2/dist/drm/i915/display/intel_lvds.c
b/sys/external/bsd/drm2/dist/drm/i915/display/intel_lvds.c
--- a/sys/external/bsd/drm2/dist/drm/i915/display/intel_lvds.c 2021-12-18
23:45:30.0 +
+++ b/sys/external/bsd/drm2/dist/drm/i915/display/intel_lvds.c 2022-04-12
10:28:48.162488466 +
@@ -962,11 +962,6 @@
if (fixed_mode)
goto out;
- /* Failed to get EDID, what about VBT? */
- fixed_mode = intel_panel_vbt_fixed_mode(intel_connector);
- if (fixed_mode)
- goto out;
-
/*
* If we didn't get EDID, try checking if the panel is already turned
* on. If so, assume that whatever is currently programmed is the
@@ -977,8 +972,12 @@
DRM_DEBUG_KMS("using current (BIOS) mode: ");
drm_mode_debug_printmodeline(fixed_mode);
fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
+ goto out;
}
+ /* Failed to get current mode, what about VBT? */
+ fixed_mode = intel_panel_vbt_fixed_mode(intel_connector);
+
/* If we still don't have a mode after all that, give up. */
if (!fixed_mode)
goto failed;
```
Going by the kernel messages, on 9.2, the old DRM fails to find a VBT:
```
kern info: [drm] failed to find VBIOS tables
i915drmkms0: interrupting at ioapic0 pin 16 (i915drmkms0)
intelfb0 at i915drmkms0
intelfb0: framebuffer at 0xd700687fb000, size 1366x768, depth 32,
stride 5504
kern error:
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_fifo_underrun.c:230)cpt_set_fifo_underrun_reporting]
*ERROR* uncleared pch fifo underrun on pch transcoder A
kern error:
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_fifo_underrun.c:381)intel_pch_fifo_underrun_irq_handler]
*ERROR* PCH transcoder A FIFO underrun
wsdisplay0 at intelfb0 kbdmux 1: console (default, vt100 emulation), using
wskbd0
```
but, somehow still picks the correct native mode (1366x768) and everything
is fine. The new DRM code, _does_ seem to find a VBT, but picks a
non-native resolution (1024x768) in UEFI mode and the display gets messed
up. In CSM mode, 1366x768 is correctly picked from the VBT.
I'll try to chase this down further when I have the time, but, somebody who
_knows_ this stuff would obviously make quicker progress.
-RVP
Emulating missing linux syscalls
Hello, I have submitted my draft proposal on gsoc platform. Could you review it and let me know what you think? Thank you in advance Ahmed Ehab
Re: Emulating missing linux syscalls
In article , Joerg Sonnenberger wrote: >Am Tue, Apr 12, 2022 at 12:29:21PM - schrieb Christos Zoulas: >> In article >, >> Piyush Sachdeva wrote: >> >-=-=-=-=-=- >> > >> >Dear Stephen Borrill, >> >My name is Piyush, and I was looking into the >> >'Emulating missing Linux syscalls' project hoping to contribute >> >to this year's GSoC. >> > >> >I wanted to be sure of a few basic things before I go ahead: >> >- linux binaries are found in- src/sys/compat/linux >> >- particular implementation in - src/sys/compat/linux/common >> >- a few architecture-specific implementations in- >> > src/sys/compat/linux/arch/. >> >- The src/sys/compat/linux/arch//linux_syscalls.c file >> > lists of system calls, and states if a particular syscall is present or >> >not. >> > >> >I was planning to work on the 'sendfile()' syscall, which I believe >> >is unimplemented for amd64 and a few other architectures as well. >> > >> >Considering the above points, I was hoping you could point me in >> >the right direction for this project. Hope to hear from you soon. >> >> I would look into porting the FreeBSD implementation of sendfile to NetBSD. > >sendfile(2) for Linux compat can be emulated in the kernel without >backing. That said, a real splice(2) or even splicev(2) would be really >nice to have. But that's a different project and arguable, a potentially >more generally useful one, too. Yes, splice is more general (as opposed to send a file to a socket), but I think splice has limitations too (one of the fds needs to be a pipe). Is that true only for linux? christos
Re: Emulating missing linux syscalls
Am Tue, Apr 12, 2022 at 12:29:21PM - schrieb Christos Zoulas: > In article > , > Piyush Sachdeva wrote: > >-=-=-=-=-=- > > > >Dear Stephen Borrill, > >My name is Piyush, and I was looking into the > >'Emulating missing Linux syscalls' project hoping to contribute > >to this year's GSoC. > > > >I wanted to be sure of a few basic things before I go ahead: > >- linux binaries are found in- src/sys/compat/linux > >- particular implementation in - src/sys/compat/linux/common > >- a few architecture-specific implementations in- > > src/sys/compat/linux/arch/. > >- The src/sys/compat/linux/arch//linux_syscalls.c file > > lists of system calls, and states if a particular syscall is present or > >not. > > > >I was planning to work on the 'sendfile()' syscall, which I believe > >is unimplemented for amd64 and a few other architectures as well. > > > >Considering the above points, I was hoping you could point me in > >the right direction for this project. Hope to hear from you soon. > > I would look into porting the FreeBSD implementation of sendfile to NetBSD. sendfile(2) for Linux compat can be emulated in the kernel without backing. That said, a real splice(2) or even splicev(2) would be really nice to have. But that's a different project and arguable, a potentially more generally useful one, too. Joerg
Re: Emulating missing linux syscalls
In article , Piyush Sachdeva wrote: >-=-=-=-=-=- > >Dear Stephen Borrill, >My name is Piyush, and I was looking into the >'Emulating missing Linux syscalls' project hoping to contribute >to this year's GSoC. > >I wanted to be sure of a few basic things before I go ahead: >- linux binaries are found in- src/sys/compat/linux >- particular implementation in - src/sys/compat/linux/common >- a few architecture-specific implementations in- > src/sys/compat/linux/arch/. >- The src/sys/compat/linux/arch//linux_syscalls.c file > lists of system calls, and states if a particular syscall is present or >not. > >I was planning to work on the 'sendfile()' syscall, which I believe >is unimplemented for amd64 and a few other architectures as well. > >Considering the above points, I was hoping you could point me in >the right direction for this project. Hope to hear from you soon. I would look into porting the FreeBSD implementation of sendfile to NetBSD. christos
Re: framebuffer refresh rate and geometry
On Tue, 12 Apr 2022, Michael van Elst wrote: wsconsctl learned about the edid attribute in -current. Either a pullup is necessary, or you can try with the -current binary. Yah--this is with a recent -HEAD. On older versions I used the ioctl directly. No joy even in CSM mode, which is the only way DRM runs properly on my HW. -RVP
