Hi Andriy,
On Tue, 17 Apr 2012 00:09:08 +0300, Andriy Gapon wrote:
> It seems that Module Configuration Type ("ECC", "No Parity", etc) is not
> reported for DDR2 and DDR3 module types. Not sure if resolution could be as
> easy as adding sdram_module_configuration_type() calls in the corresponding
> decode procedures.
Won't be so easy. For DDR2 there is one new bit to decode
(Address/Command Parity). For DDR3 byte 11 has a completely different
meaning, and the information seem to be no longer available. As I read
the specification, the only way to tell if a DDR3 module has any form
of parity or ECC is to check the extra bus width in bits 4-3 of byte 8.
But this is a boolean type of information then, telling "there is some
form of data error detection/correction". No way to tell between parity
and ECC AFAICS, and information about Address/Command Parity is gone
too.
I am attaching two patches, one for DDR2, one for DDR3, please give
them a try.
--
Jean Delvare
---
eeprom/decode-dimms | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
--- i2c-tools.orig/eeprom/decode-dimms 2011-02-16 14:58:41.000000000 +0100
+++ i2c-tools/eeprom/decode-dimms 2012-04-17 10:22:06.784083856 +0200
@@ -525,16 +525,21 @@ sub sdram_voltage_interface_level($)
return ($_[0] < @levels) ? $levels[$_[0]] : "Undefined!";
}
-# Common to SDR and DDR SDRAM
+# Common to SDR, DDR and DDR2 SDRAM
sub sdram_module_configuration_type($)
{
- my @types = (
- "No Parity", # 0
- "Parity", # 1
- "ECC", # 2
- );
+ my $byte = $_[0] & 0x07;
+ my @edc;
- return ($_[0] < @types) ? $types[$_[0]] : "Undefined!";
+ return "No Parity" if $byte == 0;
+
+ # Data ECC includes Data Parity so don't print both
+ push @edc, "Data Parity" if ($byte & 0x03) == 0x01;
+ push @edc, "Data ECC" if ($byte & 0x02);
+ # New in DDR2 specification
+ push @edc, "Address/Command Parity" if ($byte & 0x04);
+
+ return join ", ", @edc;
}
# Parameter: EEPROM bytes 0-127 (using 3-62)
@@ -1019,6 +1024,9 @@ sub decode_ddr2_sdram($)
printl("Voltage Interface Level",
sdram_voltage_interface_level($bytes->[8]));
+ printl("Module Configuration Type",
+ sdram_module_configuration_type($bytes->[11]));
+
printl("Refresh Rate", ddr2_refresh_rate($bytes->[12]));
my @burst;
---
eeprom/decode-dimms | 2 ++
1 file changed, 2 insertions(+)
--- i2c-tools.orig/eeprom/decode-dimms 2012-04-17 10:22:06.000000000 +0200
+++ i2c-tools/eeprom/decode-dimms 2012-04-17 10:42:10.205990901 +0200
@@ -1169,6 +1169,8 @@ sub decode_ddr3_sdram($)
printl("SDRAM Device Width", (1 << (($bytes->[7] & 7) + 2))." bits");
+ printl("Bus Width Extension", ($bytes->[8] & 24)." bits");
+
my $taa;
my $trcd;
my $trp;
