The suspend-imx6.S is introduced recently for suspend low-level assembly
code. Since function v7_cpu_resume() is only used by suspend support,
it makes sense to move the function into suspend-imx6.S, and control the
build of the file with CONFIG_SUSPEND option.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
i.MX6SL's suspend in ocram function is derived from i.MX6Q,
it can lower the DDR IO power from ~10mA@1.2V to ~1mA@1.2V,
measured on i.MX6SL EVK board, SH5.
Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
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>