u-boot/arch/arm/cpu/armv7/sunxi
Siarhei Siamashka 7e40e1926a sunxi: dram: Remove broken impedance and ODT configuration code
We can safely remove it, because none of the currently supported
boards uses these features.

The existing implementation had multiple problems:
   - unnecessary code duplication between sun4i/sun5i/sun7i
   - ZQ calibration was never initiated explicitly, and could be
     only triggered by setting the highest bit in the 'zq' parameter
     in the 'dram_para' struct (this was never actually done for
     any of the known Allwinner devices).
   - even if the ZQ calibration could be started, no attempts were
     made to wait for its completion, or checking whether the
     default automatically initiated ZQ calibration is still
     in progress
   - ODT was only ever enabled on sun4i, but not on sun5i/sun7i

Additionally, SDR_IOCR was set to 0x00cc0000 only on sun4i. There
are some hints in the Rockchip Linux kernel sources, indicating
that these bits are related to the automatic I/O power down
feature, which is poorly understood on sunxi hardware at the
moment. Avoiding to set these bits on sun4i too does not seem to
have any measurable/visible impact.

The impedance and ODT configuration code will be re-introdeced in
one of the next comits.

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 08:42:32 +02:00
..
board.c sunxi: Add CONFIG_MACPWR option 2014-07-31 15:37:23 +02:00
clock.c sunxi: add sun7i clocks and timer support. 2014-05-25 16:12:12 +02:00
clock_sun4i.c ahci: provide sunxi SATA driver using AHCI platform framework 2014-07-31 15:37:22 +02:00
config.mk sunxi: non-FEL SPL boot support for sun7i 2014-05-25 16:31:03 +02:00
cpu_info.c sunxi: Add sun5i support 2014-07-06 20:12:44 +01:00
dram.c sunxi: dram: Remove broken impedance and ODT configuration code 2014-08-12 08:42:32 +02:00
Makefile sunxi: HYP/non-sec: add sun7i PSCI backend 2014-07-31 15:37:24 +02:00
pinmux.c sunxi: add sun7i pinmux and gpio support 2014-05-25 16:12:21 +02:00
psci.S sunxi: HYP/non-sec: add sun7i PSCI backend 2014-07-31 15:37:24 +02:00
start.c sunxi: add sun7i cpu, board and start of day support 2014-05-25 16:12:40 +02:00
timer.c sunxi: add sun7i clocks and timer support. 2014-05-25 16:12:12 +02:00
u-boot-spl-fel.lds sunxi: Add i2c support 2014-07-18 19:41:30 +01:00
u-boot-spl.lds sunxi: Add i2c support 2014-07-18 19:41:30 +01:00