|
Hi,
I am using spd_82801.c file to get the SPD values
of the my DDR SDRAM. I have checked the values and it seem to be
correct.
Now I want to program the DRAM registers. When I
was browsing the 440gx code, I could found that these SPD values are not used
directly to
get the DRAM register value.
I could not understand the step used to
calculate the DRAM register values. In the specification I could see only the
description of DRAM register, not the
steps to calculate the value of DRAM register.
Where can I find those steps? How do you get to know for the 440gx ? Is it ok to
hardcode the values ?
I am going for this option because our system is a
embedded system, so the configuration will not change.
Also while browsing the 440gx code, I found
that most of the register are left with default values. Can any one
giving some idea about the set of registers which I need to
program. I have attached the output of the SPD
program. But how to calculate the DRAM register values like DRB, DRT, DRC,FDHC
and etc.,
The Output of the SPD_82801.c file on my DDR
SDRAM:
[root@wipro2 scanspd]# ./spd_82801ba
dev=1f, fn=3 IO_BASE=5000 After reset status 0x40 SLOT 0 After reset status 0x40 Number of bytes used by module manufacturer 0x80 After reset status 0x40 Memory Type 0x07 ---------------> DDR SDRAM After reset status 0x40 Number of Row Address bits 0x0d After reset status 0x40 Number of Column Address bits 0x0a After reset status 0x40 Number of Sides 0x01 After reset status 0x40 DIMM Configuratio type 0x00 After reset status 0x40 Refresh Rate 0x82-------------------------------> refresh rate is 7.8 micro sec After reset status 0x40 Number of Banks 0xa0 After reset status 0x40 Module Bank Density 0x40 After reset status 0x40 SPD Revision Code 0x00 After reset status 0x40 CAS # Latency 0x0c -----------------------> 2.5 After reset status 0x40 Min Row Precharge 0x50 After reset status 0x40 Min RAS to CAS Delay 0x50 ------------------------------> 20 ns After reset status 0x40 Min RAS Pulse Width 0x2d [root@wipro2 scanspd]# Thanks,
Siva
|
**************************Disclaimer************************************************** Information contained in this E-MAIL being proprietary to Wipro Limited is 'privileged' and 'confidential' and intended for use only by the individual or entity to which it is addressed. You are notified that any use, copying or dissemination of the information contained in the E-MAIL in any manner whatsoever is strictly prohibited.
****************************************************************************************
