The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Possible dependencies:
b389286d0234 ("drm/mgag200: Fix PLL setup for G200_SE_A rev >=4") 877507bb954e ("drm/mgag200: Provide per-device callbacks for PIXPLLC") 8aeeb3144fe2 ("drm/mgag200: Provide per-device callbacks for BMC synchronization") f639f74a7895 ("drm/mgag200: Add per-device callbacks") 1baf9127c482 ("drm/mgag200: Replace simple-KMS with regular atomic helpers") 4f4dc37e374c ("drm/mgag200: Reorganize before dropping simple-KMS helpers") ed2ef21f1089 ("drm/mgag200: Store primary plane's color format in CRTC state") 2d70b9a1482e ("drm/mgag200: Acquire I/O-register lock in atomic_commit_tail function") 1ee181fe958a ("drm/mgag200: Move DAC-register setup into model-specific code") 44373151ab42 ("drm/mgag200: Split mgag200_modeset_init()") 98da4b99a052 ("drm/mgag200: Store maximum resolution and memory bandwidth in device info") 21e74bf99596 ("drm/mgag200: Store HW_BUG_NO_STARTADD flag in device info") b9a577a407d9 ("drm/mgag200: Add struct mgag200_device_info") b62d943e9686 ("drm/mgag200: Implement new init logic") d45e32c9d98c ("drm/mgag200: Call mgag200_device_probe_vram() from per-model init") ce19021fd99a ("drm/mgag200: Move PCI-option setup into model-specific code") 85397f6bc4ff ("drm/mgag200: Initialize each model in separate function") 73f54d5d9682 ("drm/mgag200: Remove special case for G200SE with <2 MiB") 475e2b970cc3 ("drm/mgag200: Split up connector's mode_valid helper") 69340e529a06 ("drm/mgag200: Test memory requirements in drm_mode_config_funcs.mode_valid")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b389286d0234e1edbaf62ed8bc0892a568c33662 Mon Sep 17 00:00:00 2001 From: Jocelyn Falempe jfalempe@redhat.com Date: Thu, 13 Oct 2022 15:28:10 +0200 Subject: [PATCH] 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-jfalem...
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;