From 8e024f13142fbbca5fbe14a6926516a45bd70c3a Mon Sep 17 00:00:00 2001 From: Ben Skeggs Date: Tue, 16 Mar 2010 08:45:07 +1000 Subject: [PATCH] drm/nouveau: bail out of auxch transaction if we repeatedly recieve defers There's one known case where we never stop recieving DEFER, and loop here forever. Lets not do that.. Signed-off-by: Ben Skeggs --- drivers/gpu/drm/nouveau/nouveau_dp.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index f954ad93e81f..deeb21c6865c 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -483,7 +483,7 @@ nouveau_dp_auxch(struct nouveau_i2c_chan *auxch, int cmd, int addr, ctrl |= (cmd << NV50_AUXCH_CTRL_CMD_SHIFT); ctrl |= ((data_nr - 1) << NV50_AUXCH_CTRL_LEN_SHIFT); - for (;;) { + for (i = 0; i < 16; i++) { nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x80000000); nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl); nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x00010000); @@ -502,6 +502,12 @@ nouveau_dp_auxch(struct nouveau_i2c_chan *auxch, int cmd, int addr, break; } + if (i == 16) { + NV_ERROR(dev, "auxch DEFER too many times, bailing\n"); + ret = -EREMOTEIO; + goto out; + } + if (cmd & 1) { if ((stat & NV50_AUXCH_STAT_COUNT) != data_nr) { ret = -EREMOTEIO;