drm/nv50/disp: prevent false output detection on the original nv50

[~andy/linux] / drivers / gpu / drm / nouveau / core / engine / disp / dacnv50.c

diff --git a/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c b/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c
index f02fd9f443fff3e1178b40cedda50ee4e9ba5461..a66b27c0fcab2fa75ff1ef6e8a1e988a1b663408 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c
+++ b/drivers/gpu/drm/nouveau/core/engine/disp/dacnv50.c
@@ -49,18 +49,23 @@ int
 nv50_dac_sense(struct nv50_disp_priv *priv, int or, u32 loadval)
 {
        const u32 doff = (or * 0x800);
-       int load = -EINVAL;
+
        nv_mask(priv, 0x61a004 + doff, 0x807f0000, 0x80150000);
        nv_wait(priv, 0x61a004 + doff, 0x80000000, 0x00000000);
+
        nv_wr32(priv, 0x61a00c + doff, 0x00100000 | loadval);
        mdelay(9);
        udelay(500);
-       nv_wr32(priv, 0x61a00c + doff, 0x80000000);
-       load = (nv_rd32(priv, 0x61a00c + doff) & 0x38000000) >> 27;
-       nv_wr32(priv, 0x61a00c + doff, 0x00000000);
+       loadval = nv_mask(priv, 0x61a00c + doff, 0xffffffff, 0x00000000);
+
        nv_mask(priv, 0x61a004 + doff, 0x807f0000, 0x80550000);
        nv_wait(priv, 0x61a004 + doff, 0x80000000, 0x00000000);
-       return load;
+
+       nv_debug(priv, "DAC%d sense: 0x%08x\n", or, loadval);
+       if (!(loadval & 0x80000000))
+               return -ETIMEDOUT;
+
+       return (loadval & 0x38000000) >> 27;
 }
 
 int