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* ppc4xx: Autocalibration can set RDCC to over aggressive value.Adam Graham2009-02-12-29/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The criteria of the AMCC SDRAM Controller DDR autocalibration U-Boot code is to pick the largest passing write/read/compare window that also has the smallest SDRAM_RDCC.[RDSS] Read Sample Cycle Select value. On some Kilauea boards the DDR autocalibration algorithm can find a large passing write/read/compare window with a small SDRAM_RDCC.[RDSS] aggressive value of Read Sample Cycle Select value "T1 Sample". This SDRAM_RDCC.[RDSS] Read Sample Cycle Select value of "T1 Sample" proves to be to aggressive when later on U-Boot relocates into DDR memory and executes. The memory traces on the Kilauea board are short so on some Kilauea boards the SDRAM_RDCC.[RDSS] Read Sample Cycle Select value of "T1 Sample" shows up as a potentially valid value for the DDR autocalibratiion algorithm. The fix is to define a weak default function which provides the minimum SDRAM_RDCC.[RDSS] Read Sample Cycle Select value to accept for DDR autocalibration. The default will be the "T2 Sample" value. A board developer who has a well defined board and chooses to be more aggressive can always provide their own board specific string function with the more aggressive "T1 Sample" value or stick with the default minimum SDRAM_RDCC.[RDSS] value of "T2". Also put in a autocalibration loop fix for case where current write/read/compare passing window size is the same as a prior window size, then in this case choose the write/read/compare result that has the associated smallest RDCC T-Sample value. Signed-off-by: Adam Graham <agraham@amcc.com> Signed-off-by: Stefan Roese <sr@denx.de>
* rename CFG_ macros to CONFIG_SYSJean-Christophe PLAGNIOL-VILLARD2008-10-18-4/+4
| | | | Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
* ppc4xx: Reset and relock memory DLL after SDRAM_CLKTR changeAdam Graham2008-10-08-0/+21
| | | | | | | | | | | | After changing SDRAM_CLKTR phase value rerun the memory preload initialization sequence (INITPLR) to reset and relock the memory DLL. Changing the SDRAM_CLKTR memory clock phase coarse timing adjustment effects the phase relationship of the internal, to the PPC chip, and external, to the PPC chip, versions of MEMCLK_OUT. Signed-off-by: Adam Graham <agraham@amcc.com> Signed-off-by: Victor Gallardo <vgallardo@amcc.com> Signed-off-by: Stefan Roese <sr@denx.de>
* Revert "ppc4xx: Fix DDR2 auto calibration on Kilauea 600MHz (200MHz PLB)"Stefan Roese2008-09-22-0/+5
| | | | | | This reverts commit 3eec160a3a405b29ce9c06920f6427b9047dd8a8. Signed-off-by: Stefan Roese <sr@denx.de>
* ppc4xx: Fix DDR2 auto calibration on Kilauea 600MHz (200MHz PLB)Victor Gallardo2008-09-16-5/+0
| | | | | | Signed-off-by: Victor Gallardo <vgallardo@amcc.com> Signed-off-by: Adam Graham <agraham@amcc.com> Signed-off-by: Stefan Roese <sr@denx.de>
* ppc4xx: IBM Memory Controller DDR autocalibration routinesAdam Graham2008-09-05-0/+1212
Alternate SDRAM DDR autocalibration routine that can be generically used for any PPC4xx chips that have the IBM SDRAM Controller core allowing for support of more DIMM/memory chip vendors and gets the DDR autocalibration values which give the best read latency performance (SDRAM0_RDCC.[RDSS]). Two alternate SDRAM DDR autocalibration algoritm are provided in this patch, "Method_A" and "Method_B". DDR autocalibration Method_A scans the full range of possible PPC4xx SDRAM Controller DDR autocalibration values and takes a lot longer to run than Method_B. Method_B executes in the same amount of time as the currently existing DDR autocalibration routine, i.e. 1 second or so. Normally Method_B is used and it is set as the default method. The current U-Boot PPC4xx DDR autocalibration code calibrates the IBM SDRAM Controller registers.[bit-field]: 1) SDRAM0_RQDC.[RQFD] 2) SDRAM0_RFDC.[RFFD] This alternate PPC4xx DDR autocalibration code calibrates the following IBM SDRAM Controller registers.[bit-field]: 1) SDRAM0_WRDTR.[WDTR] 2) SDRAM0_CLKTR.[CKTR] 3) SDRAM0_RQDC.[RQFD] 4) SDRAM0_RFDC.[RFFD] and will also use the calibrated settings of the above four registers that produce the best "Read Sample Cycle Select" value in the SDRAM0_RDCC.[RDSS] register.[bit-field]. Signed-off-by: Adam Graham <agraham@amcc.com> Signed-off-by: Stefan Roese <sr@denx.de>