From 4e57382faa4bcad285baee21737de2c99ba6baad Mon Sep 17 00:00:00 2001 From: York Sun Date: Fri, 26 Aug 2011 11:32:43 -0700 Subject: powerpc/mpc8xxx: Add DDR2 to unified DDR driver DDR2 has different ODT table and values. Adding table according to Samsung application note. Fix additive latency calculation to avoid interger underflow. Also converted typedef dynamic_odt_t to struct dynamic_odt. Signed-off-by: York Sun Signed-off-by: Kumar Gala --- doc/README.fsl-ddr | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) (limited to 'doc/README.fsl-ddr') diff --git a/doc/README.fsl-ddr b/doc/README.fsl-ddr index c1ee0a68a8..abfb7f192d 100644 --- a/doc/README.fsl-ddr +++ b/doc/README.fsl-ddr @@ -170,3 +170,55 @@ Single slot system Reference http://www.xrosstalkmag.com/mag_issues/xrosstalk_oct08_final.pdf http://download.micron.com/pdf/technotes/ddr3/tn4108_ddr3_design_guide.pdf + + +Table for ODT for DDR2 +====================== +Two slots system ++-----------------------+----------+---------------+-----------------------------+-----------------------------+ +| Configuration | |DRAM controller| Slot 1 | Slot 2 | ++-----------+-----------+----------+-------+-------+--------------+--------------+--------------+--------------+ +| | | | | | Rank 1 | Rank 2 | Rank 1 | Rank 2 | ++ Slot 1 | Slot 2 |Write/Read| Write | Read |-------+------+-------+------+-------+------+-------+------+ +| | | | | | Write | Read | Write | Read | Write | Read | Write | Read | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 1 | off | 150 | off | off | off | off | 75 | 75 | off | off | +| Dual Rank | Dual Rank |----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 2 | off | 150 | 75 | 75 | off | off | off | off | off | off | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 1 | off | 150 | off | off | off | off | 75 | 75 | | | +| Dual Rank |Single Rank|----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 2 | off | 150 | 75 | 75 | off | off | off | off | | | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 1 | off | 150 | off | off | | | 75 | 75 | off | off | +|Single Rank| Dual Rank |----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 2 | off | 150 | 75 | 75 | | | off | off | off | off | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 1 | off | 150 | off | off | | | 75 | 75 | | | +|Single Rank|Single Rank|----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| | | Slot 2 | off | 150 | 75 | 75 | | | off | off | | | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| Dual Rank | Empty | Slot 1 | off | 75 | 150 | off | off | off | | | | | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| Empty | Dual Rank | Slot 2 | off | 75 | | | | | 150 | off | off | off | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +|Single Rank| Empty | Slot 1 | off | 75 | 150 | off | | | | | | | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ +| Empty |Single Rank| Slot 2 | off | 75 | | | | | 150 | off | | | ++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+ + +Single slot system ++-------------+------------+---------------+-----------------------------+ +| | |DRAM controller| Rank 1 | Rank 2 | +|Configuration| Write/Read |-------+-------+-------+------+-------+------+ +| | | Write | Read | Write | Read | Write | Read | ++-------------+------------+-------+-------+-------+------+-------+------+ +| | R1 | off | 75 | 150 | off | off | off | +| Dual Rank |------------+-------+-------+-------+------+-------+------+ +| | R2 | off | 75 | 150 | off | off | off | ++-------------+------------+-------+-------+-------+------+-------+------+ +| Single Rank | R1 | off | 75 | 150 | off | ++-------------+------------+-------+-------+-------+------+ + +Reference http://www.samsung.com/global/business/semiconductor/products/dram/downloads/applicationnote/ddr2_odt_control_200603.pdf + -- cgit v1.2.3