diff options
| author | Jocelyn Falempe <jfalempe@redhat.com> | 2022-10-13 15:28:10 +0200 |
|---|---|---|
| committer | Jocelyn Falempe <jfalempe@redhat.com> | 2022-10-18 16:06:10 +0200 |
| commit | b389286d0234e1edbaf62ed8bc0892a568c33662 (patch) | |
| tree | ed89898ad55f56c19723413c19eaef37819aaf7a | |
| parent | a140a6a2d5ec0329ad05cd3532a91ad0ce58dceb (diff) | |
drm/mgag200: Fix PLL setup for G200_SE_A rev >=4
For G200_SE_A, PLL M setting is wrong, which leads to blank screen,
or "signal out of range" on VGA display.
previous code had "m |= 0x80" which was changed to
m |= ((pixpllcn & BIT(8)) >> 1);
Tested on G200_SE_A rev 42
This line of code was moved to another file with
commit 877507bb954e ("drm/mgag200: Provide per-device callbacks for
PIXPLLC") but can be easily backported before this commit.
v2: * put BIT(7) First to respect MSB-to-LSB (Thomas)
* Add a comment to explain that this bit must be set (Thomas)
Fixes: 2dd040946ecf ("drm/mgag200: Store values (not bits) in struct mgag200_pll_values")
Cc: stable@vger.kernel.org
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20221013132810.521945-1-jfalempe@redhat.com
| -rw-r--r-- | drivers/gpu/drm/mgag200/mgag200_g200se.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/gpu/drm/mgag200/mgag200_g200se.c b/drivers/gpu/drm/mgag200/mgag200_g200se.c index be389ed91cbd..bd6e573c9a1a 100644 --- a/drivers/gpu/drm/mgag200/mgag200_g200se.c +++ b/drivers/gpu/drm/mgag200/mgag200_g200se.c @@ -284,7 +284,8 @@ static void mgag200_g200se_04_pixpllc_atomic_update(struct drm_crtc *crtc, pixpllcp = pixpllc->p - 1; pixpllcs = pixpllc->s; - xpixpllcm = pixpllcm | ((pixpllcn & BIT(8)) >> 1); + // For G200SE A, BIT(7) should be set unconditionally. + xpixpllcm = BIT(7) | pixpllcm; xpixpllcn = pixpllcn; xpixpllcp = (pixpllcs << 3) | pixpllcp; |