arm: mx6: ddr: add pd_fast_exit flag to system information
authorTim Harvey <tharvey@gateworks.com>
Fri, 3 Apr 2015 23:52:52 +0000 (16:52 -0700)
committerStefano Babic <sbabic@denx.de>
Wed, 22 Apr 2015 12:35:35 +0000 (14:35 +0200)
commit78c5a180871d4337d4cfd41d6739a04b271b2e4d
tree2aaac7ec7a70f9b06587d64996d4e12b699422c4
parent32f9ef3e2ba813ea541f08c551b9188ef4749307
arm: mx6: ddr: add pd_fast_exit flag to system information

DDR3 has a special Precharge power-down mode: fast-exit vs slow-exit.

In slow-exit mode the DLL is off but in some quiescent state that makes it easy
to turn on again in tXPDLL cycles (about 10tCK) vs the full tDLLK (512tCK).
In fast-exist mode the DLL is maintained such that it is ready again in about
3tCK.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
arch/arm/cpu/armv7/mx6/ddr.c
arch/arm/include/asm/arch-mx6/mx6-ddr.h