[coreboot-gerrit] Change in coreboot[master]: [WIP] plot 2D write margins

[Angel Pons (Code Review)]

Angel Pons has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/48398 )

Change subject: [WIP] plot 2D write margins
......................................................................

[WIP] plot 2D write margins

Looks like they don't work as intended

Change-Id: Id76e7f292fdb3813a8dd973273b17279b74ac5c1
Signed-off-by: Angel Pons 
---
M src/northbridge/intel/sandybridge/raminit_common.c
1 file changed, 48 insertions(+), 11 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/98/48398/1

diff --git a/src/northbridge/intel/sandybridge/raminit_common.c b/src/northbridge/intel/sandybridge/raminit_common.c
index 3efabdb..667ec14 100644
--- a/src/northbridge/intel/sandybridge/raminit_common.c
+++ b/src/northbridge/intel/sandybridge/raminit_common.c
@@ -2723,6 +2723,9 @@
 int aggressive_write_training(ramctr_timing *ctrl)
 {
    const u8 wr_vref_offsets[3] = { 0, 0x0f, 0x2f };
+
+	const bool sweep_vref = 0 && CONFIG(RAMINIT_PLOT_READ_MARGINS);
+
    int i, pat;

int lower[NUM_CHANNELS][NUM_SLOTRANKS][NUM_LANES];
@@ -2749,12 +2752,20 @@

printram("discover tx_dq write:\n");

-	for (i = 0; i < ARRAY_SIZE(wr_vref_offsets); i++) {
-		FOR_ALL_POPULATED_CHANNELS {
-			set_write_vref(channel, wr_vref_offsets[i]);
+	const int max_vref_idx = sweep_vref ? 63 : ARRAY_SIZE(wr_vref_offsets);

-			for (pat = 0; pat < NUM_PATTERNS; pat++) {
-				FOR_ALL_POPULATED_RANKS {
+	FOR_ALL_POPULATED_CHANNELS {
+		FOR_ALL_POPULATED_RANKS {
+			printram("channel %d, rank %d\n", channel, slotrank);
+
+			for (i = 0; i < max_vref_idx; i++) {
+				const int vref = i >= 32 ? i : 31 - i;
+				set_write_vref(channel, sweep_vref ? vref : wr_vref_offsets[i]);
+
+				if (sweep_vref)
+					printram("% 5d:\t", 31 - i);
+
+				for (pat = 0; pat < NUM_PATTERNS; pat++) {
    				int tx_dq;
    				u32 raw_stats[MAX_TX_DQ + 1];
    				int stats[MAX_TX_DQ + 1];
@@ -2771,10 +2782,24 @@
    					}
    					program_timings(ctrl, channel);

+						MCHBAR32(IOSAV_BYTE_SERROR_C_ch(channel));
+
    					test_aggressive_write(ctrl, channel, slotrank);

raw_stats[tx_dq] = MCHBAR32(
    						IOSAV_BYTE_SERROR_C_ch(channel));
+
+						if (!sweep_vref)
+							continue;
+
+						printram("%02x ", raw_stats[tx_dq] & 0xff);
+
+#if 0
+						if (i == 31 && tx_dq == (MAX_TX_DQ + 1) / 2)
+							printram("%c", raw_stats[tx_dq] & 0xff ? 'X' : '+');
+						else
+							printram("%c", raw_stats[tx_dq] & 0xff ? '#' : '.');
+#endif
    				}
    				FOR_ALL_LANES {
    					struct run rn;
@@ -2792,12 +2817,6 @@

return MAKE_ERR;
    					}
-						printram("tx_dq: %d, %d, %d: "
-							 "0x%02x-0x%02x-0x%02x, "
-							 "0x%02x-0x%02x\n", channel, slotrank,
-							 i, rn.start, rn.middle, rn.end,
-							 rn.start + ctrl->tx_dq_offset[i],
-							 rn.end   - ctrl->tx_dq_offset[i]);

lower[channel][slotrank][lane] =
    						MAX(rn.start + ctrl->tx_dq_offset[i],
@@ -2807,9 +2826,27 @@
    						MIN(rn.end - ctrl->tx_dq_offset[i],
    						    upper[channel][slotrank][lane]);

+						if (sweep_vref)
+							continue;
+
+						printram("tx_dq: %d, %d, %d: "
+							 "0x%02x-0x%02x-0x%02x, "
+							 "0x%02x-0x%02x\n", channel, slotrank,
+							 i, rn.start, rn.middle, rn.end,
+							 rn.start + ctrl->tx_dq_offset[i],
+							 rn.end   - ctrl->tx_dq_offset[i]);
    				}
+
+					if (sweep_vref)
+						printram(" ");
    			}
+
+				if (sweep_vref)
+					printram("\n");
    		}
+
+			if (sweep_vref)
+				printram("\n");
    	}
    }