On exynos mcpm systems the firmware is hardcoded to jump to an address
in SRAM (0x02073000) when secondary CPUs come up. By default the
firmware puts a bunch of code at that location. That code expects the
kernel to fill in a few slots with addresses that it uses to jump back
to the kernel's entry point for secondary CPUs.
Originally (on prerelease hardware) this firmware code contained a
bunch of workarounds to deal with boot ROM bugs. However on all
shipped hardware we simply use this code to redirect to a kernel
function for bringing up the CPUs.
Let's stop relying on the code provided by the bootloader and just
plumb in our own (simple) code jump to the kernel. This has the nice
benefit of fixing problems due to the fact that older bootloaders
(like the one shipped on the Samsung Chromebook 2) might have put
slightly different code into this location.
Once suspend/resume is implemented for systems using exynos-mcpm we'll
need to make sure we reinstall our fixed up code after resume. ...but
that's not anything new since IRAM (and thus the address of the
mcpm_entry_point) is lost across suspend/resume anyway.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Since commit 166aaf39 ("ARM: 8029/1: mcpm: Rename the power_down_finish()
functions to be less confusing") changed the name of power_down_finish to
wait_for_cpu_powerdown, so use new member name wait_for_cpu_powerdown.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
The exynos5800 is very similar to exynos5420. We can re-use
the existing MCPM support for exynos5800 for secondary boot
-up and switching.
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Add machine-dependent MCPM call-backs for Exynos5420. These are used
to power up/down the secondary CPUs during boot, shutdown, s2r and
switching.
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Inderpal Singh <inderpal.s@samsung.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
