From df4cf1b72d726d788388858673fa61e42fdb9ad8 Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Thu, 1 Jul 2010 11:31:45 +1000 Subject: [PATCH] drm/nv50: DCB quirk for Dell M6300 Uncertain if this is a weirdo configuration, or a BIOS bug. If it's not a BIOS bug, we still don't know how to make it work anyway so ignore a "conflicting" DCB entry to prevent a display hang. Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nouveau_bios.c | 28 ++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_bios.c b/drivers/gpu/drm/nouveau/nouveau_bios.c index 2e8cdd71a6e..3e274d57d9b 100644 --- a/drivers/gpu/drm/nouveau/nouveau_bios.c +++ b/drivers/gpu/drm/nouveau/nouveau_bios.c @@ -5841,6 +5841,31 @@ void merge_like_dcb_entries(struct drm_device *dev, struct dcb_table *dcb) dcb->entries = newentries; } +static bool +apply_dcb_encoder_quirks(struct drm_device *dev, int idx, u32 *conn, u32 *conf) +{ + /* Dell Precision M6300 + * DCB entry 2: 02025312 00000010 + * DCB entry 3: 02026312 00000020 + * + * Identical, except apparently a different connector on a + * different SOR link. Not a clue how we're supposed to know + * which one is in use if it even shares an i2c line... + * + * Ignore the connector on the second SOR link to prevent + * nasty problems until this is sorted (assuming it's not a + * VBIOS bug). + */ + if ((dev->pdev->device == 0x040d) && + (dev->pdev->subsystem_vendor == 0x1028) && + (dev->pdev->subsystem_device == 0x019b)) { + if (*conn == 0x02026312 && *conf == 0x00000020) + return false; + } + + return true; +} + static int parse_dcb_table(struct drm_device *dev, struct nvbios *bios, bool twoHeads) { @@ -5974,6 +5999,9 @@ parse_dcb_table(struct drm_device *dev, struct nvbios *bios, bool twoHeads) if ((connection & 0x0000000f) == 0x0000000f) continue; + if (!apply_dcb_encoder_quirks(dev, i, &connection, &config)) + continue; + NV_TRACEWARN(dev, "Raw DCB entry %d: %08x %08x\n", dcb->entries, connection, config); -- 2.46.0