From b517694b399946815a558e7b71be67b86fa8fa14 Mon Sep 17 00:00:00 2001 From: Emil Velikov Date: Thu, 22 Aug 2013 23:00:06 +0100 Subject: [PATCH] drm/nv50/disp: prevent false output detection on the original nv50 Commit ea9197cc323839ef3d5280c0453b2c622caa6bc7 effectively enabled the use of an improved DAC detection code, but introduced a regression on the original nv50 chipset, causing a ghost monitor to be detected. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67382 Signed-off-by: Emil Velikov --- drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c b/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c index f02fd9f..15df527 100644 --- a/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c +++ b/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c @@ -55,7 +55,14 @@ nv50_dac_sense(struct nv50_disp_priv *priv, int or, u32 loadval) nv_wr32(priv, 0x61a00c + doff, 0x00100000 | loadval); mdelay(9); udelay(500); - nv_wr32(priv, 0x61a00c + doff, 0x80000000); + + /* + * The original nv50 detects a ghost monitor if we do the following + * write. See fdo#67382 for more information + */ + if (nv_device(priv)->chipset != 0x50) + nv_wr32(priv, 0x61a00c + doff, 0x80000000); + load = (nv_rd32(priv, 0x61a00c + doff) & 0x38000000) >> 27; nv_wr32(priv, 0x61a00c + doff, 0x00000000); nv_mask(priv, 0x61a004 + doff, 0x807f0000, 0x80550000); -- 1.8.3.4