u-boot/arch
Siarhei Siamashka 5c18384dea sunxi: dram: Re-introduce the impedance calibration ond ODT
The DRAM controller allows to configure impedance either by using the
calibration against an external high precision 240 ohm resistor, or
by skipping the calibration and loading pre-defined data. The DRAM
controller register guide is available here:

    http://linux-sunxi.org/A10_DRAM_Controller_Register_Guide#SDR_ZQCR0

The new code supports both of the impedance configuration modes:
   - If the higher bits of the 'zq' parameter in the 'dram_para' struct
     are zero, then the lowest 8 bits are used as the ZPROG value, where
     two divisors encoded in lower and higher 4 bits. One divisor is
     used for calibrating the termination impedance, and another is used
     for the output impedance.
   - If bits 27:8 in the 'zq' parameters are non-zero, then they are
     used as the pre-defined ZDATA value instead of performing the ZQ
     calibration.

Two lowest bits in the 'odt_en' parameter enable ODT for the DQ and DQS
lines individually. Enabling ODT for both DQ and DQS means that the
'odt_en' parameter needs to be set to 3.

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2014-08-12 08:42:33 +02:00
..
arc kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
arm sunxi: dram: Re-introduce the impedance calibration ond ODT 2014-08-12 08:42:33 +02:00
avr32 kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
blackfin kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
m68k kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
microblaze kconfig: add board Kconfig and defconfig files 2014-07-30 08:48:01 -04:00
mips kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
nds32 kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
nios2 kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
openrisc kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
powerpc Merge branch 'master' of git://git.denx.de/u-boot-mpc85xx 2014-08-06 08:38:18 -04:00
sandbox kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
sh kconfig: add board Kconfig and defconfig files 2014-07-30 08:48:01 -04:00
sparc kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
x86 kconfig: delete redundant CONFIG_${ARCH} definition 2014-07-30 14:42:02 -04:00
.gitignore .gitignore: drop include/asm/proc from ignore pattern 2014-06-19 11:18:54 -04:00
Kconfig kconfig: add basic Kconfig files 2014-07-30 08:48:02 -04:00