Re: [PATCH v2 24/24] arm64: dts: qcom: eliza: Reduce OS PDC DRV span to 0x10000

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Reducing the PDC `reg` size to 0x10000 triggers a hardcoded warning in `drivers/irqchip/qcom-pdc.c` and fails to actually reduce the mapped region size.
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commit 5004f072e69f0ca2826142cbc32ed05f15a06f65
Author: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>

arm64: dts: qcom: eliza: Reduce OS PDC DRV span to 0x10000

This commit reduces the size of the first reg entry in the OS PDC DRV
register window on eliza from 0x40000 to 0x10000.

> diff --git a/arch/arm64/boot/dts/qcom/eliza.dtsi b/arch/arm64/boot/dts/qcom/eliza.dtsi
> index 4a7a0ac40ce62..24f92ca9f9ef4 100644
> --- a/arch/arm64/boot/dts/qcom/eliza.dtsi
> +++ b/arch/arm64/boot/dts/qcom/eliza.dtsi
> @@ -885,7 +885,7 @@ lpass_lpicx_noc: interconnect@7420000 {
>  
>  		pdc: interrupt-controller@b220000 {
>  			compatible = "qcom,eliza-pdc", "qcom,pdc";
> -			reg = <0x0 0x0b220000 0x0 0x40000>,
> +			reg = <0x0 0x0b220000 0x0 0x10000>,

[Severity: Medium]
Does this introduce a regression by triggering an invalid reg size warning
during boot?

Looking at drivers/irqchip/qcom-pdc.c, qcom_pdc_probe() calculates the
mapping size like this:

    res_size = max_t(resource_size_t, resource_size(&res), QCOM_PDC_SIZE);

where QCOM_PDC_SIZE is defined as 0x30000. If the resource size from the
device tree is smaller than QCOM_PDC_SIZE, the driver issues a warning:

    pr_warn("%pOF: invalid reg size, please fix DT\n", node);

Since this reduces the size to 0x10000, res_size evaluates to max(0x10000,
0x30000) = 0x30000. Will the driver still ioremap 0x30000 bytes despite
this change, and emit the warning on every boot?

>  			      <0x0 0x174000f0 0x0 0x64>;

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Sashiko AI review · https://sashiko.dev/#/patchset/20260527094333.2311731-1-mukesh.ojha@oss.qualcomm.com?part=24