linux-stable.git/drivers/gpu/drm/mgag200, branch linux-5.17.y

mgag200 fix memmapsl configuration in GCTL6 register

2022-04-08T11:57:27+00:00

commit 028a73e10705af1ffd51f2537460f616dc58680e upstream.

On some servers with MGA G200_SE_A (rev 42), booting with Legacy BIOS,
the hardware hangs when using kdump and kexec into the kdump kernel.
This happens when the uncompress code tries to write "Decompressing Linux"
to the VGA Console.

It can be reproduced by writing to the VGA console (0xB8000) after
booting to graphic mode, it generates the following error:

kernel:NMI: PCI system error (SERR) for reason a0 on CPU 0.
kernel:Dazed and confused, but trying to continue

The root cause is the configuration of the MGA GCTL6 register

According to the GCTL6 register documentation:

bit 0 is gcgrmode:
    0: Enables alpha mode, and the character generator addressing system is
     activated.
    1: Enables graphics mode, and the character addressing system is not
     used.

bit 1 is chainodd even:
    0: The A0 signal of the memory address bus is used during system memory
     addressing.
    1: Allows A0 to be replaced by either the A16 signal of the system
     address (ifmemmapsl is ‘00’), or by the hpgoddev (MISC<5>, odd/even
     page select) field, described on page 3-294).

bit 3-2 are memmapsl:
    Memory map select bits 1 and 0. VGA.
    These bits select where the video memory is mapped, as shown below:
        00 => A0000h - BFFFFh
        01 => A0000h - AFFFFh
        10 => B0000h - B7FFFh
        11 => B8000h - BFFFFh

bit 7-4 are reserved.

Current code set it to 0x05 => memmapsl to b01 => 0xa0000 (graphic mode)
But on x86, the VGA console is at 0xb8000 (text mode)
In arch/x86/boot/compressed/misc.c debug strings are written to 0xb8000
As the driver doesn't use this mapping at 0xa0000, it is safe to set it to
0xb8000 instead, to avoid kernel hang on G200_SE_A rev42, with kexec/kdump.

Thus changing the value 0x05 to 0x0d

Signed-off-by: Jocelyn Falempe 
Reviewed-by: Javier Martinez Canillas 
Acked-by: Lyude Paul 
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Zimmermann 
Link: https://patchwork.freedesktop.org/patch/msgid/20220119102905.1194787-1-jfalempe@redhat.com
Signed-off-by: Greg Kroah-Hartman

drm/mgag200: Fix PLL setup for g200wb and g200ew

2022-03-13T19:35:06+00:00

commit f86c3ed55920 ("drm/mgag200: Split PLL setup into compute and
 update functions") introduced a regression for g200wb and g200ew.
The PLLs are not set up properly, and VGA screen stays
black, or displays "out of range" message.

MGA1064_WB_PIX_PLLC_N/M/P was mistakenly replaced with
MGA1064_PIX_PLLC_N/M/P which have different addresses.

Patch tested on a Dell T310 with g200wb

Fixes: f86c3ed55920 ("drm/mgag200: Split PLL setup into compute and update functions")
Cc: stable@vger.kernel.org
Signed-off-by: Jocelyn Falempe 
Signed-off-by: Thomas Zimmermann 
Link: https://patchwork.freedesktop.org/patch/msgid/20220308174321.225606-1-jfalempe@redhat.com

drm: Move nomodeset kernel parameter to the DRM subsystem

2021-11-27T12:52:22+00:00

The "nomodeset" kernel cmdline parameter is handled by the vgacon driver
but the exported vgacon_text_force() symbol is only used by DRM drivers.

It makes much more sense for the parameter logic to be in the subsystem
of the drivers that are making use of it.

Let's move the vgacon_text_force() function and related logic to the DRM
subsystem. While doing that, rename it to drm_firmware_drivers_only() and
make it return true if "nomodeset" was used and false otherwise. This is
a better description of the condition that the drivers are testing for.

Suggested-by: Daniel Vetter 
Signed-off-by: Javier Martinez Canillas 
Acked-by: Thomas Zimmermann 
Acked-by: Jani Nikula 
Acked-by: Pekka Paalanen 
Acked-by: Greg Kroah-Hartman 
Link: https://patchwork.freedesktop.org/patch/msgid/20211112133230.1595307-4-javierm@redhat.com

drm/format-helper: Rework format-helper memcpy functions

2021-11-11T11:06:57+00:00

Move destination-buffer clipping from all format-helper memcpy
function into callers. Support destination-buffer pitch. Only
distinguish between system and I/O memory, but use same logic
everywhere.

Signed-off-by: Thomas Zimmermann 
Tested-by: Noralf Trønnes 
Reviewed-by: Noralf Trønnes 
Link: https://patchwork.freedesktop.org/patch/msgid/20211110103702.374-3-tzimmermann@suse.de

drm/mgag200: Use managed interfaces for framebuffer write combining

2021-09-23T07:26:09+00:00

Replace arch_phys_wc_add() and arch_io_reserve_memtype_wc() with
the rsp managed functions. Allows for removing the cleanup code
for memory management

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Hans de Goede 
Link: https://patchwork.freedesktop.org/patch/msgid/20210916181601.9146-5-tzimmermann@suse.de

drm/mgag200: Fix uninitialized variable delta

2021-08-18T18:47:59+00:00

The variable delta is not initialized and this will cause unexpected
behaviour with the comparison of tmpdelta < delta. Fix this by setting
it to 0xffffffff. This matches the behaviour as in the similar function
mgag200_pixpll_compute_g200se_04.

v2:
	* move fix up by one line to align style with other functions
	* add additional tags from similar patch

Signed-off-by: Colin Ian King 
Fixes: 2545ac960364 ("drm/mgag200: Abstract pixel PLL via struct mgag200_pll")
Addresses-Coverity: ("Uninitialized scalar variable")
Reviewed-by: Daniel Vetter 
Reviewed-by: Thomas Zimmermann 
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Signed-off-by: Thomas Zimmermann 
Cc: Sam Ravnborg 
Cc: Dave Airlie 
Cc: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210817163204.494166-1-colin.king@canonical.com

drm/mgag200: Use offset-adjusted shadow-plane mappings

2021-08-08T18:27:30+00:00

For framebuffers with non-zero offset fields, shadow-plane helpers
provide a pointer to the first byte of the contained data. Use it in
mgag200.

Signed-off-by: Thomas Zimmermann 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20210803125928.27780-6-tzimmermann@suse.de

drm/mgag200: Compute PLL values during atomic check

2021-08-08T18:14:14+00:00

PLL setup can fail if the display mode's clock is not supported by
any PLL configuration. Compute the PLL values during atomic check, so
that atomic commits can fail at the appropriate time. If successful,
use the values in the atomic-update phase.

Signed-off-by: Thomas Zimmermann 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20210714142240.21979-14-tzimmermann@suse.de

drm/mgag200: Introduce custom CRTC state

2021-08-08T18:14:12+00:00

Inherit from struct drm_crtc_state by embeding it and providing the
rsp callbacks for simple-kms helpers. No functional changes.

The new state struct mgag200_crtc_state will hold PLL values for modeset
operations.

v2:
	* move the simple-kms changes into a separate patch (Sam)

Signed-off-by: Thomas Zimmermann 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20210714142240.21979-13-tzimmermann@suse.de

drm/mgag200: Abstract pixel PLL via struct mgag200_pll

2021-08-08T18:14:05+00:00

Move all PLL compute and update functions into mgag200_pll.c. No
functional changes to the rsp algorithms.

Introduce struct mgag200_pll and mgag200_pll_funcs. The data strutures
abstract the details of each revision's PLL. Perform calls to compute
and update functionality via function pointers. Init the PLL once as
part of the driver initialization.

Signed-off-by: Thomas Zimmermann 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20210714142240.21979-11-tzimmermann@suse.de