When system enter suspend, we can set the DDR IO to
high-Z state to save DDR IOs' power consumption, this
operation can save many power(from ~26mA@1.5V to ~15mA@1.5V,
measured on i.MX6Q SabreSD board, R25) of DDR IOs. To
achieve that, we need to copy the suspend code to ocram
and run the low level hardware related code(set DDR IOs
to high-Z state) in ocram.
If there is no ocram space available, then system will
still do suspend in external DDR, hence no DDR IOs will
be set to high-Z.
The OCRAM usage layout is as below,
ocram suspend region(4K currently):
======================== high address ======================
.
.
.
^
^
^
imx6_suspend code
PM_INFO structure(imx6_cpu_pm_info)
======================== low address =======================
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Only mx508 based board is mach-mx50_rdp and it has been marked as BROKEN
for several releases.
mx508 currently lacks clock support.
In case someone needs to add mx508 support back, then the recommended approach
is to use device tree.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
It moves a bunch of header files included in hardware.h and itself
from mach-imx/include/mach to mach-imx, and updates users to include
hardware.h rather than mach/hardware.h. The files in mach-imx/devices
will need to include "../hardware.h".
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>