DDR3: Decode the FTB fields of tCk, tAA, tRCD, tRP and tRC.
---
eeprom/decode-dimms | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
--- i2c-tools.orig/eeprom/decode-dimms 2013-04-10 14:12:37.739202969 +0200
+++ i2c-tools/eeprom/decode-dimms 2013-04-10 14:17:03.383357005 +0200
@@ -1329,6 +1329,17 @@ sub decode_ddr2_sdram($)
printl_cond($bytes->[46], "PLL Relock Time", $bytes->[46] . " us");
}
+# Return combined time in ns
+sub ddr3_mtb_ftb($$$$)
+{
+ my ($byte1, $byte2, $mtb, $ftb) = @_;
+
+ # byte1 is unsigned in ns, but byte2 is signed in ps
+ $byte2 -= 0x100 if $byte2 & 0x80;
+
+ return $byte1 * $mtb + $byte2 * $ftb / 1000;
+}
+
# Parameter: EEPROM bytes 0-127 (using 3-76)
sub decode_ddr3_sdram($)
{
@@ -1358,7 +1369,7 @@ sub decode_ddr3_sdram($)
# speed
prints("Memory Characteristics");
- $ctime = $bytes->[12] * $mtb;
+ $ctime = ddr3_mtb_ftb($bytes->[12], $bytes->[34], $mtb, $ftb);
my $ddrclk = 2 * (1000 / $ctime);
my $tbits = 1 << (($bytes->[8] & 7) + 3);
my $pcclk = int ($ddrclk * $tbits / 8);
@@ -1390,12 +1401,12 @@ sub decode_ddr3_sdram($)
my $trp;
my $tras;
- $taa = ceil($bytes->[16] / $bytes->[12]);
- $trcd = ceil($bytes->[18] / $bytes->[12]);
- $trp = ceil($bytes->[20] / $bytes->[12]);
- $tras = ceil(((($bytes->[21] & 0x0f) << 8) + $bytes->[22]) /
$bytes->[12]);
+ $taa = ddr3_mtb_ftb($bytes->[16], $bytes->[35], $mtb, $ftb);
+ $trcd = ddr3_mtb_ftb($bytes->[18], $bytes->[36], $mtb, $ftb);
+ $trp = ddr3_mtb_ftb($bytes->[20], $bytes->[37], $mtb, $ftb);
+ $tras = ((($bytes->[21] & 0x0f) << 8) + $bytes->[22]) * $mtb;
- printl("tCL-tRCD-tRP-tRAS", join("-", $taa, $trcd, $trp, $tras));
+ printl("tCL-tRCD-tRP-tRAS", ddr_core_timings(ceil($taa / $ctime),
$ctime, $trcd, $trp, $tras));
# latencies
my $highestCAS = 0;
@@ -1417,7 +1428,7 @@ sub decode_ddr3_sdram($)
printl("Minimum Row Active to Row Active Delay (tRRD)",
tns3($bytes->[19] * $mtb));
printl("Minimum Active to Auto-Refresh Delay (tRC)",
- tns3((((($bytes->[21] >> 4) & 15) << 8) + $bytes->[23]) *
$mtb));
+ tns3(ddr3_mtb_ftb((($bytes->[21] & 0xf0) << 4) + $bytes->[23],
$bytes->[38], $mtb, $ftb)));
printl("Minimum Recovery Delay (tRFC)",
tns3((($bytes->[25] << 8) + $bytes->[24]) * $mtb));
printl("Minimum Write to Read CMD Delay (tWTR)",
--
Jean Delvare
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