[0/5] Add APCS support for SDX55

Message

Manivannan Sadhasivam Jan. 4, 2021, 8:11 a.m. UTC

Hello,

This series adds APCS mailbox and clock support for SDX55. The APCS IP
in SDX55 provides IPC and clock functionalities. Hence, mailbox support
is added to the "qcom-apcs-ipc-mailbox" driver and a dedicated clock
driver "apcs-sdx55" is added.

Also, the clock to the APCS block is coming from 3 different sources:

1. Board XO
2. Fixed rate GPLL0
3. A7 PLL

First source is from crystal osc, second is from GCC and third one is a
separate clock source. Hence, a dedicated clk driver is added for the A7
PLL as well.

Apart from the mailbox support, another intention of this series is to add
the CPUFreq support to SDX55 platform. Since there is no dedicated hardware
IP in SDX55 to do CPUFreq duties, this platform makes use of the clock and
regulators directly via cpufreq-dt driver.

The trick here is attaching the power domain to cpudev. Usually the power
domains for the target device is attached in the bus driver or in the
dedicated device drivers. But in this case, there is no dedicated CPUFreq
driver nor a bus driver. After discussing with Viresh, I concluded that
A7 PLL driver might be the best place to do this!

But this decision is subject to discussion, hence added Ulf and Viresh to
this series.

Thanks,
Mani

Manivannan Sadhasivam (5):
  dt-bindings: mailbox: Add binding for SDX55 APCS
  mailbox: qcom: Add support for SDX55 APCS IPC
  dt-bindings: clock: Add Qualcomm A7 PLL binding
  clk: qcom: Add A7 PLL support
  clk: qcom: Add SDX55 APCS clock controller support

 .../devicetree/bindings/clock/qcom,a7pll.yaml |  51 ++++++
 .../mailbox/qcom,apcs-kpss-global.yaml        |  59 +++++--
 drivers/clk/qcom/Kconfig                      |  17 ++
 drivers/clk/qcom/Makefile                     |   2 +
 drivers/clk/qcom/a7-pll.c                     | 100 ++++++++++++
 drivers/clk/qcom/apcs-sdx55.c                 | 149 ++++++++++++++++++
 drivers/mailbox/qcom-apcs-ipc-mailbox.c       |   5 +
 7 files changed, 374 insertions(+), 9 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/qcom,a7pll.yaml
 create mode 100644 drivers/clk/qcom/a7-pll.c
 create mode 100644 drivers/clk/qcom/apcs-sdx55.c