On 2/28/25 11:39 AM, Alexander Stein wrote:
Am Donnerstag, 27. Februar 2025, 23:21:22 CET schrieb Frank Li:
On Thu, Feb 27, 2025 at 10:34:20PM +0100, Marek Vasut wrote:
On 2/27/25 10:27 PM, Frank Li wrote:
[...]
+ gpu: gpu@4d900000 {
+ compatible = "fsl,imx95-mali", "arm,mali-valhall-csf";
+ reg = <0 0x4d900000 0 0x480000>;
+ clocks = <&scmi_clk IMX95_CLK_GPU>;
+ clock-names = "core";
+ interrupts = <GIC_SPI 288 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 289 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 290 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "gpu", "job", "mmu";
+ mali-supply = <&gpu_fixed_reg>;
+ operating-points-v2 = <&gpu_opp_table>;
+ power-domains = <&scmi_devpd IMX95_PD_GPU>, <&scmi_perf IMX95_PERF_GPU>;
+ power-domain-names = "mix", "perf";
+ resets = <&gpu_blk_ctrl 0>;
+ #cooling-cells = <2>;
+ dynamic-power-coefficient = <1013>;
+ status = "disabled";
GPU is internal module, which have not much dependence with other module
such as pinmux. why not default status is "disabled". Supposed gpu driver
will turn off clock and power if not used.
My thinking was that there are MX95 SoC with GPU fused off, hence it is
better to keep the GPU disabled in DT by default. But I can also keep it
enabled and the few boards which do not have MX95 SoC with GPU can
explicitly disable it in board DT.
What do you think ?
GPU Fuse off should use access-control, see thread
https://lore.kernel.org/imx/20250207120213.GD14860@localhost.localdomain/
Did that thread ever go anywhere ? It seems there is no real conclusion, is
there ? +Cc Alex .
The direction is use access-control to indicate fuse disable. Only
implement detail is under discussion.
Well, the discussion ended up to be more complicated for i.MX8M.
Aren't we missing the access controller in MX95 DT so far ?
And maybe some driver to match ?
For i.MX95
things are a bit easier, as fuses and clocks are controlled by System
Manager (SM), accessed using SCMI. [1] is more important for imx95.
I think SCMI is replacing GPL code in kernel with stubs that call
non-free firmware, which removes flexibility and makes long term (or
any) maintenance much more complicated.
