diff options
| author | Dave Gerlach <d-gerlach@ti.com> | 2022-04-09 14:12:15 -0700 |
|---|---|---|
| committer | Nishanth Menon <nm@ti.com> | 2022-04-22 18:12:35 -0500 |
| commit | f226041424cf87245d39a1b2dfae304308b36b6b (patch) | |
| tree | febf01dd536de03e3b004e5d1100d01b367e1a4d /include/linux/wkup_m3_ipc.h | |
| parent | 12eeb74925da70eb39d90abead9de9793be3d4c8 (diff) | |
soc: ti: wkup_m3_ipc: Add support for toggling VTT regulator
Some boards like the AM335x EVM-SK and AM437x GP EVM provide software
control via a GPIO pin to toggle the DDR VTT regulator to reduce power
consumption in low power states.
The VTT regulator should be disabled after enabling self-refresh on
suspend, and should be enabled before disabling self-refresh on resume.
This is to allow proper self-refresh entry/exit commands to be
transmitted to the memory.
The "ti,vtt-gpio-pin" device tree property in the wkup_m3_ipc node
specifies which GPIO pin to use. This property is communicated to the
Wakeup Cortex M3 co-processor where the actual toggling of the GPIO pin
happens in CM3 firmware [1].
Please note that the GPIO pin must be on the GPIO0 module as that module
is in the wakeup power domain.
[1] https://git.ti.com/cgit/processor-firmware/ti-amx3-cm3-pm-firmware/tree/src/pm_services/ddr.c?h=08.02.00.006#n190
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
[dfustini: remove the unnecessary "ti,needs-vtt-toggle" property]
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Link: https://lore.kernel.org/r/20220409211215.2529387-3-dfustini@baylibre.com
Diffstat (limited to 'include/linux/wkup_m3_ipc.h')
| -rw-r--r-- | include/linux/wkup_m3_ipc.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/wkup_m3_ipc.h b/include/linux/wkup_m3_ipc.h index 3f496967b538..2bc52c6381d5 100644 --- a/include/linux/wkup_m3_ipc.h +++ b/include/linux/wkup_m3_ipc.h @@ -33,6 +33,7 @@ struct wkup_m3_ipc { int mem_type; unsigned long resume_addr; + int vtt_conf; int state; struct completion sync_complete; |