The following changes are based on kernel UCC ethernet performance:

1.  Make the CSB bus pipeline depth as 4, and enable the repeat mode
2.  Optimize transactions between QE and CSB.  Added CFG_SPCR_OPT
    switch to enable this setting.

The following changes are based on the App Note AN3369 and
verified to improve memory latency using LMbench:

3.  CS0_CONFIG[AP_n_EN] is changed from 1 to 0
4.  CS0_CONFIG[ODT_WR_CONFIG] set to 1.  Was a reserved setting
    previously.
5.  TIMING_CFG_1[WRREC] is changed from 3clks to 2clks  (based on
    Twr=15ns, and this was already the setting in DDR_MODE)
6.  TIMING_CFG_1[PRETOACT] is changed from 3clks to 2clks. (based on
    Trp=15ns)
7.  TIMING_CFG_1[ACTTOPRE] is changed from 9clks to 6clks. (based on
    Tras=40ns)
8.  TIMING_CFG_1[ACTTORW] is changed from 3clks to 2clks. (based on
    Trcd=15ns)
9.  TIMING_CFG_1[REFREC] changed from 21 clks to 11clks.  (based on
    Trfc=75ns)
10. TIMING_CFG_2[FOUR_ACT] is changed from 10 clks to 7clks.  (based
    on Tfaw=50ns)
11. TIMING_CFG_2[ADD_LAT] and DDR_MODE[AL] changed from 0 to 1 (based
    on CL=3 and WL=2).

Signed-off-by: Michael Barkowski <michael.barkowski@freescale.com>
Acked-by: Kim Phillips <kim.phillips@freescale.com>