[PATCH v4 6/8] arm64: dts: add SRAM, MHU mailbox and SCPI support on Juno
From: Sudeep Holla <hidden>
Date: 2015-06-08 14:33:04
Also in:
linux-clk, linux-pm, lkml
On 08/06/15 14:51, Jon Medhurst (Tixy) wrote:
On Mon, 2015-06-08 at 11:40 +0100, Sudeep Holla wrote: [...]quoted
+ + scpi { + compatible = "arm,scpi"; + mboxes = <&mailbox 1>; + shmem = <&cpu_scp_hpri>; + + clocks { + compatible = "arm,scpi-clocks"; + + scpi_dvfs: scpi_clocks at 0 { + compatible = "arm,scpi-dvfs-clocks"; + #clock-cells = <1>; + clock-indices = <0>, <1>, <2>; + clock-output-names = "vbig", "vlittle", "vgpu";From where do the clock names derive? They look more like names for voltage domains rather than clocks. My (admittedly very old) Juno docs, have the clocks as ATLCLK, APLCLK and GPUCLK.
I agree, I just copied it from SCPI spec which just deals with power domain names in the context of DVFS. I will update as per Juno doc.
quoted
+ }; + scpi_clk: scpi_clocks at 3 { + compatible = "arm,scpi-variable-clocks"; + #clock-cells = <1>; + clock-indices = <3>, <4>; + clock-output-names = "pxlclk0", "pxlclk1";Can we also have clock index 5, name 'i2s_clk', for used by audio? (I don't know what other clocks the SCP currently supports, but audio is one being currently used by the out-of-tree code).
I will update.
Also, I believe that both display outputs share the same clock, and so pxlclk0 and pxlclk1 can't be controlled independently. But I guess these device-tree entries are for the interface to the SCP firmware, not the hardware, and if that pretends the clocks are independent...
Yes, this is bit tricky, I will let Liviu answer this. Regards, Sudeep