[PATCH v3 7/8] riscv: dts: thead: th1520: Add IMG BXM-4-64 GPU node

[Michal Wilczynski]

On 6/3/25 14:27, Ulf Hansson wrote:
> On Fri, 30 May 2025 at 00:24, Michal Wilczynski
> <m.wilczynski at samsung.com> wrote:
>>
>> Add a device tree node for the IMG BXM-4-64 GPU present in the T-HEAD
>> TH1520 SoC used by the Lichee Pi 4A board. This node enables support for
>> the GPU using the drm/imagination driver.
>>
>> By adding this node, the kernel can recognize and initialize the GPU,
>> providing graphics acceleration capabilities on the Lichee Pi 4A and
>> other boards based on the TH1520 SoC.
>>
>> Add fixed clock gpu_mem_clk, as the MEM clock on the T-HEAD SoC can't be
>> controlled programatically.
>>
>> Signed-off-by: Michal Wilczynski <m.wilczynski at samsung.com>
>> ---
>>  arch/riscv/boot/dts/thead/th1520.dtsi | 22 ++++++++++++++++++++++
>>  1 file changed, 22 insertions(+)
>>
>> diff --git a/arch/riscv/boot/dts/thead/th1520.dtsi b/arch/riscv/boot/dts/thead/th1520.dtsi
>> index 6170eec79e919b606a2046ac8f52db07e47ef441..ee937bbdb7c08439a70306f035b1cc82ddb4bae2 100644
>> --- a/arch/riscv/boot/dts/thead/th1520.dtsi
>> +++ b/arch/riscv/boot/dts/thead/th1520.dtsi
>> @@ -225,6 +225,13 @@ aonsys_clk: clock-73728000 {
>>                 #clock-cells = <0>;
>>         };
>>
>> +       gpu_mem_clk: mem-clk {
>> +               compatible = "fixed-clock";
>> +               clock-frequency = <0>;
>> +               clock-output-names = "gpu_mem_clk";
>> +               #clock-cells = <0>;
>> +       };
>> +
>>         stmmac_axi_config: stmmac-axi-config {
>>                 snps,wr_osr_lmt = <15>;
>>                 snps,rd_osr_lmt = <15>;
>> @@ -504,6 +511,21 @@ clk: clock-controller at ffef010000 {
>>                         #clock-cells = <1>;
>>                 };
>>
>> +               gpu: gpu at ffef400000 {
>> +                       compatible = "thead,th1520-gpu", "img,img-bxm-4-64",
>> +                                    "img,img-rogue";
>> +                       reg = <0xff 0xef400000 0x0 0x100000>;
>> +                       interrupt-parent = <&plic>;
>> +                       interrupts = <102 IRQ_TYPE_LEVEL_HIGH>;
>> +                       clocks = <&clk_vo CLK_GPU_CORE>,
>> +                                <&gpu_mem_clk>,
>> +                                <&clk_vo CLK_GPU_CFG_ACLK>;
>> +                       clock-names = "core", "mem", "sys";
>> +                       power-domains = <&aon TH1520_GPU_PD>;
>> +                       power-domain-names = "a";
> 
> If the power-domain-names are really needed, please pick a
> useful/descriptive name.

Yeah they are required. Even though this convention doesn't seem to be
enforced by the dt-binding it seems like it's hard-coded into the driver
330e76d31697 ("drm/imagination: Add power domain control"). So I don't
think I have any choice here.

> 
> [...]
> 
> Kind regards
> Uffe
> 

Best regards,
-- 
Michal Wilczynski <m.wilczynski at samsung.com>