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authorYork Sun <yorksun@freescale.com>2011-01-10 12:03:00 +0000
committerKumar Gala <galak@kernel.crashing.org>2011-01-19 22:58:23 -0600
commite1fd16b6f5e80d932c73f5a36141adfb35126e83 (patch)
tree7a1bda7894afa9187f50936172aff0529324d7b1 /doc
parentd2a9568c57f0aa02f097911d3811e002a1eec1b8 (diff)
downloadu-boot-linaro-stable-e1fd16b6f5e80d932c73f5a36141adfb35126e83.tar.gz
mpc85xx: Enable unique mode registers and dynamic ODT for DDR3
Added fsl_ddr_get_version() function to for DDR3 to poll DDRC IP version (major, minor, errata) to determine if unique mode registers are available. If true, always use unique mode registers. Dynamic ODT is enabled if needed. The table is documented in doc/README.fsl-ddr. This function may also need to be extend for future other platforms if such a feature exists. Enable address parity and RCW by default for RDIMMs. Change default output driver impedance from 34 ohm to 40ohm. Make it 34ohm for quad-rank RDIMMs. Use a formula to calculate rodt_on for timing_cfg_5. Signed-off-by: York Sun <yorksun@freescale.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'doc')
-rw-r--r--doc/README.fsl-ddr67
1 files changed, 66 insertions, 1 deletions
diff --git a/doc/README.fsl-ddr b/doc/README.fsl-ddr
index 9e3c5390d..a7ba193f3 100644
--- a/doc/README.fsl-ddr
+++ b/doc/README.fsl-ddr
@@ -104,4 +104,69 @@ Combination of hwconfig
Hwconfig can be combined with multiple parameters, for example, on a supported
platform
-hwconfig=fsl_ddr:addr_hash=true,ctlr_intlv=cacheline,bank_intlv=cs0_cs1_cs2_cs3
+hwconfig=fsl_ddr:addr_hash=true,ctlr_intlv=cacheline,bank_intlv=cs0_cs1_cs2_cs3,ecc=on
+
+Table for dynamic ODT for DDR3
+==============================
+For single-slot system with quad-rank DIMM and dual-slot system, dynamic ODT may
+be needed, depending on the configuration. The numbers in the following tables are
+in Ohms.
+
+* denotes dynamic ODT
+
+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 | 75 | 120 | off | off | off | off | off | 30 | 30 |
+| Dual Rank | Dual Rank |----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 2 | off | 75 | off | off | 30 | 30 | 120 | off | off | off |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 1 | off | 75 | 120 | off | off | off | 20 | 20 | | |
+| Dual Rank |Single Rank|----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 2 | off | 75 | off | off | 20 | 20 | 120 *| off | | |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 1 | off | 75 | 120 *| off | | | off | off | 20 | 20 |
+|Single Rank| Dual Rank |----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 2 | off | 75 | 20 | 20 | | | 120 | off | off | off |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 1 | off | 75 | 120 *| off | | | 30 | 30 | | |
+|Single Rank|Single Rank|----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Slot 2 | off | 75 | 30 | 30 | | | 120 *| off | | |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| Dual Rank | Empty | Slot 1 | off | 75 | 40 | off | off | off | | | | |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| Empty | Dual Rank | Slot 2 | off | 75 | | | | | 40 | off | off | off |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+|Single Rank| Empty | Slot 1 | off | 75 | 40 | off | | | | | | |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| Empty |Single Rank| Slot 2 | off | 75 | | | | | 40 | off | | |
++-----------+-----------+----------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+
+Single slot system
++-------------+------------+---------------+-----------------------------+-----------------------------+
+| | |DRAM controller| Rank 1 | Rank 2 | Rank 3 | Rank 4 |
+|Configuration| Write/Read |-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | | Write | Read | Write | Read | Write | Read | Write | Read | Write | Read |
++-------------+------------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | R1 | off | 75 | 120 *| off | off | off | 20 | 20 | off | off |
+| |------------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | R2 | off | 75 | off | 20 | 120 | off | 20 | 20 | off | off |
+| Quad Rank |------------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | R3 | off | 75 | 20 | 20 | off | off | 120 *| off | off | off |
+| |------------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | R4 | off | 75 | 20 | 20 | off | off | off | 20 | 120 | off |
++-------------+------------+-------+-------+-------+------+-------+------+-------+------+-------+------+
+| | R1 | off | 75 | 40 | off | off | off |
+| Dual Rank |------------+-------+-------+-------+------+-------+------+
+| | R2 | off | 75 | 40 | off | off | off |
++-------------+------------+-------+-------+-------+------+-------+------+
+| Single Rank | R1 | off | 75 | 40 | off |
++-------------+------------+-------+-------+-------+------+
+
+Reference http://www.xrosstalkmag.com/mag_issues/xrosstalk_oct08_final.pdf
+ http://download.micron.com/pdf/technotes/ddr3/tn4108_ddr3_design_guide.pdf