drm/nouveau: Import initial memory timing work

This isn't correct everywhere yet, but since we don't use the data yet
it's perfectly safe to push in, and the information we gain from logs
will help to fix the remaining issues.

v2 (Ben Skeggs <bskeggs@redhat.com>):
- fixed up formatting
- free parsed timing info on takedown
- switched timing table printout to debug loglevel

Signed-off-by: Roy Spliet <r.spliet@student.tudelft.nl>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 144 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_mem.c b/drivers/gpu/drm/nouveau/nouveau_mem.c
index 2db01f80f38e..00b31b5e16cd 100644
--- a/drivers/gpu/drm/nouveau/nouveau_mem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_mem.c
@@ -648,3 +648,147 @@ nouveau_mem_gart_init(struct drm_device *dev)
 	return 0;
 }
 
+void
+nouveau_mem_timing_init(struct drm_device *dev)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	struct nouveau_pm_engine *pm = &dev_priv->engine.pm;
+	struct nouveau_pm_memtimings *memtimings = &pm->memtimings;
+	struct nvbios *bios = &dev_priv->vbios;
+	struct bit_entry P;
+	u8 tUNK_0, tUNK_1, tUNK_2;
+	u8 tRP;		/* Byte 3 */
+	u8 tRAS;	/* Byte 5 */
+	u8 tRFC;	/* Byte 7 */
+	u8 tRC;		/* Byte 9 */
+	u8 tUNK_10, tUNK_11, tUNK_12, tUNK_13, tUNK_14;
+	u8 tUNK_18, tUNK_19, tUNK_20, tUNK_21;
+	u8 *mem = NULL, *entry;
+	int i, recordlen, entries;
+
+	if (bios->type == NVBIOS_BIT) {
+		if (bit_table(dev, 'P', &P))
+			return;
+
+		if (P.version == 1)
+			mem = ROMPTR(bios, P.data[4]);
+		else
+		if (P.version == 2)
+			mem = ROMPTR(bios, P.data[8]);
+		else {
+			NV_WARN(dev, "unknown mem for BIT P %d\n", P.version);
+		}
+	} else {
+		NV_DEBUG(dev, "BMP version too old for memory\n");
+		return;
+	}
+
+	if (!mem) {
+		NV_DEBUG(dev, "memory timing table pointer invalid\n");
+		return;
+	}
+
+	if (mem[0] != 0x10) {
+		NV_WARN(dev, "memory timing table 0x%02x unknown\n", mem[0]);
+		return;
+	}
+
+	/* validate record length */
+	entries   = mem[2];
+	recordlen = mem[3];
+	if (recordlen < 15) {
+		NV_ERROR(dev, "mem timing table length unknown: %d\n", mem[3]);
+		return;
+	}
+
+	/* parse vbios entries into common format */
+	memtimings->timing =
+		kcalloc(entries, sizeof(*memtimings->timing), GFP_KERNEL);
+	if (!memtimings->timing)
+		return;
+
+	entry = mem + mem[1];
+	for (i = 0; i < entries; i++, entry += recordlen) {
+		struct nouveau_pm_memtiming *timing = &pm->memtimings.timing[i];
+		if (entry[0] == 0)
+			continue;
+
+		tUNK_18 = 1;
+		tUNK_19 = 1;
+		tUNK_20 = 0;
+		tUNK_21 = 0;
+		switch (recordlen) {
+		case 0x21:
+			tUNK_21 = entry[21];
+		case 0x20:
+			tUNK_20 = entry[20];
+		case 0x19:
+			tUNK_19 = entry[19];
+		case 0x18:
+			tUNK_18 = entry[18];
+		default:
+			tUNK_0  = entry[0];
+			tUNK_1  = entry[1];
+			tUNK_2  = entry[2];
+			tRP     = entry[3];
+			tRAS    = entry[5];
+			tRFC    = entry[7];
+			tRC     = entry[9];
+			tUNK_10 = entry[10];
+			tUNK_11 = entry[11];
+			tUNK_12 = entry[12];
+			tUNK_13 = entry[13];
+			tUNK_14 = entry[14];
+			break;
+		}
+
+		timing->reg_100220 = (tRC << 24 | tRFC << 16 | tRAS << 8 | tRP);
+
+		/* XXX: I don't trust the -1's and +1's... they must come
+		 *      from somewhere! */
+		timing->reg_100224 = ((tUNK_0 + tUNK_19 + 1) << 24 |
+				      tUNK_18 << 16 |
+				      (tUNK_1 + tUNK_19 + 1) << 8 |
+				      (tUNK_2 - 1));
+
+		timing->reg_100228 = (tUNK_12 << 16 | tUNK_11 << 8 | tUNK_10);
+		if(recordlen > 19) {
+			timing->reg_100228 += (tUNK_19 - 1) << 24;
+		} else {
+			timing->reg_100228 += tUNK_12 << 24;
+		}
+
+		/* XXX: reg_10022c */
+
+		timing->reg_100230 = (tUNK_20 << 24 | tUNK_21 << 16 |
+				      tUNK_13 << 8  | tUNK_13);
+
+		/* XXX: +6? */
+		timing->reg_100234 = (tRAS << 24 | (tUNK_19 + 6) << 8 | tRC);
+		if(tUNK_10 > tUNK_11) {
+			timing->reg_100234 += tUNK_10 << 16;
+		} else {
+			timing->reg_100234 += tUNK_11 << 16;
+		}
+
+		/* XXX; reg_100238, reg_10023c */
+		NV_DEBUG(dev, "Entry %d: 220: %08x %08x %08x %08x\n", i,
+			 timing->reg_100220, timing->reg_100224,
+			 timing->reg_100228, timing->reg_10022c);
+		NV_DEBUG(dev, "         230: %08x %08x %08x %08x\n",
+			 timing->reg_100230, timing->reg_100234,
+			 timing->reg_100238, timing->reg_10023c);
+	}
+
+	memtimings->nr_timing  = entries;
+	memtimings->supported = true;
+}
+
+void
+nouveau_mem_timing_fini(struct drm_device *dev)
+{
+	struct drm_nouveau_private *dev_priv = dev->dev_private;
+	struct nouveau_pm_memtimings *mem = &dev_priv->engine.pm.memtimings;
+
+	kfree(mem->timing);
+}