On 24/11/2021 16.34, Hector Martin wrote:
This series adds the driver for the Apple PMGR device power state
registers. These registers can clockgate and (in some cases) powergate
specific SoC blocks. They also control the reset line, and can have
additional features such as automatic power management.
The current driver supports only the lowest/highest power states,
provided via the genpd framework, plus reset support provided via
the reset subsystem.
Apple's PMGRs (there are two in the T8103) have a uniform register
bit layout (sometimes with varying features). To be able to support
multiple SoC generations as well as express pd relationships
dynamically, this binding describes each PMGR power state control
as a single devicetree node. Future SoC generations are expected to
retain backwards compatibility, allowing this driver to work on them
with only DT changes.
#1: MAINTAINERS updates, to go via the SoC tree to avert merge hell
#2-#5: Adds power-domains properties to existing device bindings
#6-#7: Adds the new pmgr device tree bindings
#8: The driver itself.
#9: Instantiates the driver in t8103.dtsi. This adds the entire PMGR
node tree and references the relevant nodes from existing devices.
#7: Adds runtime-pm support to the Samsung UART driver, as a first
working consumer.
#8: Instantiates a second UART, to more easily test this.
There are currently no consumers for the reset functionality, so
it is untested, but we will be testing it soon with the NVMe driver
(as it is required to allow driver re-binding to work properly).
== Changes since v2 ==
- DT schema review comments & patch order fix
- Added the power-domains properties to devices that already mainlined
- Now adds the entire PMGR tree. This turns off all devices we do not
currently instantiate, and adds power-domains to those we do. The
nodes were initially generated with [1] and manually tweaked. all
the labels match the ADT labels (lowercased), which might be used
by the bootloader in the future to conditionally disable nodes
based on hardware configuration.
- Dropped apple,t8103-minipmgr, since I don't expect we will ever need
to tell apart multiple PMGR instances within a SoC, and added
apple,t6000-pmgr{-pwrstate} for the new SoCs.
- Driver now unconditionally enables auto-PM for all devices. This
seems to be safe and should save power (it is not implemented for
all devices; if not implemented, the bit just doesn't exist and is
ignored).
- If an always-on device is not powered on at boot, turn it on and
print a warning. This avoids the PM core complaining. We still
want to know if/when this happens, but let's not outright fail.
- Other minor fixes (use PS names instead of offsets for messages,
do not spuriously clear flag bits).
On the way the parent node is handled: I've decided that these syscon
nodes will only ever contain pwrstates and nothing else. We now size
them based on the register range that contains pwrstate controls
(rounded up to page size). t6000 has 3 PMGRs and t6001 has 4, and
we shouldn't have to care about telling apart the multiple instances.
Anything else PMGR does that needs a driver will be handled by
entirely separate nodes in the future.
Re t6001 and t6000 (and the rumored t6002), t6000 is basically a
cut-down version of t6001 (and t6002 is rumored to be two t6001
dies), down to the die floorplan, so I'm quite certain we won't need
t6001/2-specific compatibles for anything shared. The t6000 devicetree
will just #include the t6001 one and remove the missing devices.
Hence, everything for this SoC series is going to have compatibles
named apple,t6000-* (except the extra instances of some blocks in
t6001 which look like they may have differences; PMGR isn't one of
them, but some multimedia stuff might).
[1] https://github.com/AsahiLinux/m1n1/blob/main/proxyclient/tools/pmgr_adt2dt.py
Hector Martin (11):
MAINTAINERS: Add PMGR power state files to ARM/APPLE MACHINE
dt-bindings: i2c: apple,i2c: Add power-domains property
dt-bindings: iommu: apple,dart: Add power-domains property
dt-bindings: pinctrl: apple,pinctrl: Add power-domains property
dt-bindings: interrupt-controller: apple,aic: Add power-domains
property
dt-bindings: power: Add apple,pmgr-pwrstate binding
dt-bindings: arm: apple: Add apple,pmgr binding
soc: apple: Add driver for Apple PMGR power state controls
arm64: dts: apple: t8103: Add PMGR nodes
tty: serial: samsung_tty: Support runtime PM
arm64: dts: apple: t8103: Add UART2
.../bindings/arm/apple/apple,pmgr.yaml | 134 ++
.../devicetree/bindings/i2c/apple,i2c.yaml | 3 +
.../interrupt-controller/apple,aic.yaml | 3 +
.../devicetree/bindings/iommu/apple,dart.yaml | 3 +
.../bindings/pinctrl/apple,pinctrl.yaml | 3 +
.../bindings/power/apple,pmgr-pwrstate.yaml | 71 ++
MAINTAINERS | 3 +
arch/arm64/boot/dts/apple/t8103-j274.dts | 5 +
arch/arm64/boot/dts/apple/t8103-pmgr.dtsi | 1136 +++++++++++++++++
arch/arm64/boot/dts/apple/t8103.dtsi | 36 +
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/apple/Kconfig | 21 +
drivers/soc/apple/Makefile | 2 +
drivers/soc/apple/apple-pmgr-pwrstate.c | 317 +++++
drivers/tty/serial/samsung_tty.c | 93 +-
16 files changed, 1798 insertions(+), 34 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml
create mode 100644 Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml
create mode 100644 arch/arm64/boot/dts/apple/t8103-pmgr.dtsi
create mode 100644 drivers/soc/apple/Kconfig
create mode 100644 drivers/soc/apple/Makefile
create mode 100644 drivers/soc/apple/apple-pmgr-pwrstate.c
Applied everything except the samsung_tty change to asahi-soc/dt (DT
changes) and asahi-soc/pmgr (just the driver). Thanks everyone for the
reviews!
Krzysztof: feel free to take that patch through tty if you think it's in
good shape. I'm not sure how much power UART runtime-pm will save us,
but at least it's a decent test case, so it's probably worth having.
--
Hector Martin (marcan@xxxxxxxxx)
Public Key: https://mrcn.st/pub
