kernel/linux.git/arch/arm/common/mcpm_entry.c, branch linux-4.16.y

ARM: 8675/1: MCPM: ensure not to enter __hyp_soft_restart from loopback and cpu_power_down

2017-05-23T16:26:08+00:00

Commit 9da5ac236de6 ("ARM: soft-reboot into same mode that we entered the kernel") added support to enter the new kernel in the same processor mode as the previous one when we soft-reboot from one kernel into another by pass a flag to cpu_reset() so it knows what to do exactly. However it missed to make similar changes in MCPM code. Due to the missing flag, the CPUs enter HYP mode which is not supported with MCPM. MCPM works only in secure mode as it manages CCI. This patch aligns the cpu_reset call in MCPM with other changes in the above mentioned commit by making phys_reset_t to follow the prototype of cpu_reset(). Fixes: 9da5ac236de6 ("ARM: soft-reboot into same mode that we entered the kernel") Acked-by: Nicolas Pitre Signed-off-by: Sudeep Holla Signed-off-by: Russell King

ARM: 8641/1: treewide: Replace uses of virt_to_phys with __pa_symbol

2017-02-28T11:06:10+00:00

All low-level PM/SMP code using virt_to_phys() should actually use __pa_symbol() against kernel symbols. Update code where relevant to move away from virt_to_phys(). Acked-by: Russell King Reviewed-by: Laura Abbott Signed-off-by: Florian Fainelli Signed-off-by: Russell King

ARM: MCPM: remove residency argument from mcpm_cpu_suspend()

2015-05-06T15:47:10+00:00

This is currently unused. If a suspend must be limited to CPU level only by preventing the last man from triggering a cluster level suspend then this should be determined according to many other criteria the MCPM layer is currently not aware of. It is unlikely that mcpm_cpu_suspend() would be the proper conduit for that information anyway. Signed-off-by: Nicolas Pitre Acked-by: Dave Martin

ARM: MCPM: add references to the available documentation in the code

2015-05-06T15:46:15+00:00

Signed-off-by: Nicolas Pitre Acked-by: Dave Martin

ARM: MCPM: make internal helpers private to the core code

2015-05-06T15:45:46+00:00

This concerns the following helpers: __mcpm_cpu_going_down() __mcpm_cpu_down() __mcpm_outbound_enter_critical() __mcpm_outbound_leave_critical() __mcpm_cluster_state() They are and should only be used by the core code now. Therefore their declarations are removed from mcpm.h and their definitions are made static, hence the need to move them before their users which accounts for the bulk of this patch. This left the mcpm_sync_struct definition at an odd location, therefore it is moved as well with some comment clarifications. Signed-off-by: Nicolas Pitre Acked-by: Dave Martin

ARM: MCPM: remove backward compatibility code

2015-05-06T15:43:12+00:00

Now that no one uses the old callbacks anymore, let's remove them and associated support code. Signed-off-by: Nicolas Pitre Acked-by: Dave Martin

ARM: MCPM: move the algorithmic complexity to the core code

2015-04-03T19:52:46+00:00

All backends are reimplementing a variation of the same CPU reference count handling. They are also responsible for driving the MCPM special low-level locking. This is needless duplication, involving algorithmic requirements that are not necessarily obvious to the uninitiated. And from past code review experience, those were all initially implemented badly. After 3 years, it is time to refactor as much common code to the core MCPM facility to make the backends as simple as possible. To avoid a flag day, the new scheme is introduced in parallel to the existing backend interface. When all backends are converted over, the compatibility interface could be removed. The new MCPM backend interface implements simpler methods addressing very platform specific tasks performed under lock protection while keeping the algorithmic complexity and race avoidance local to the core code. Signed-off-by: Nicolas Pitre Tested-by: Daniel Lezcano Signed-off-by: Olof Johansson

ARM: 8081/1: MCPM: provide infrastructure to allow for MCPM loopback

2014-07-18T10:58:00+00:00

The kernel already has the responsibility to handle resources such as the CCI when hotplugging CPUs, during the booting of secondary CPUs, and when resuming from suspend/idle. It would be more coherent and less confusing if the CCI for the boot CPU (or cluster) was also initialized by the kernel rather than expecting the firmware/bootloader to do it and only in that case. After all, the kernel has all the necessary code already and the bootloader shouldn't have to care at all. The CCI may be turned on only when the cache is off. Leveraging the CPU suspend code to loop back through the low-level MCPM entry point is all that is needed to properly turn on the CCI from the kernel by using the same code as during secondary boot. Let's provide a generic MCPM loopback function that can be invoked by backend initialization code to set things (CCI or similar) on the boot CPU just as it is done for the other CPUs. Signed-off-by: Nicolas Pitre Reviewed-by: Kevin Hilman Tested-by: Kevin Hilman Tested-by: Doug Anderson Signed-off-by: Russell King

Merge branches 'alignment', 'fixes', 'l2c' (early part) and 'misc' into for-next

2014-06-05T11:35:52+00:00

ARM: 8029/1: mcpm: Rename the power_down_finish() functions to be less confusing

2014-05-25T22:48:12+00:00

The name "power_down_finish" seems to be causing some confusion, because it suggests that this function is responsible for taking some action to cause the specified CPU to complete its power down. This patch renames the affected functions to "wait_for_powerdown" and similar, since this function's intended purpose is just to wait for the hardware to finish a powerdown initiated by a previous cpu_power_down. Signed-off-by: Dave Martin Acked-by: Nicolas Pitre Signed-off-by: Russell King