[PATCH 2/2] perf/smmuv3: Add devicetree support

[John Garry]

On 16/11/2021 11:35, Jean-Philippe Brucker wrote:
> Add device-tree support to the SMMUv3 PMCG.  One small cosmetic change
> while factoring the option mask printout: don't display it when zero, it
> only contains one erratum at the moment.
> 
> Signed-off-by: Jay Chen <jkchen at linux.alibaba.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
> ---
>   drivers/perf/arm_smmuv3_pmu.c | 25 +++++++++++++++++++++++--
>   1 file changed, 23 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
> index 226348822ab3..958325ac103a 100644
> --- a/drivers/perf/arm_smmuv3_pmu.c
> +++ b/drivers/perf/arm_smmuv3_pmu.c
> @@ -47,6 +47,7 @@
>   #include <linux/kernel.h>
>   #include <linux/list.h>
>   #include <linux/msi.h>
> +#include <linux/of.h>
>   #include <linux/perf_event.h>
>   #include <linux/platform_device.h>
>   #include <linux/smp.h>
> @@ -750,8 +751,15 @@ static void smmu_pmu_get_acpi_options(struct smmu_pmu *smmu_pmu)
>   		smmu_pmu->options |= SMMU_PMCG_EVCNTR_RDONLY;
>   		break;
>   	}
> +}
> +
> +static void smmu_pmu_get_of_options(struct smmu_pmu *smmu_pmu)
> +{
> +	struct device_node *node = smmu_pmu->dev->of_node;
>   
> -	dev_notice(smmu_pmu->dev, "option mask 0x%x\n", smmu_pmu->options);
> +	if (of_device_is_compatible(node, "hisilicon,smmu-v3-pmcg-hip08"))

I don't think that this is necessary. We don't support DT for hip08, nor 
have any plans to. Incidentally, was this binding missing in your series?

Thanks,
John

> +		/* HiSilicon Erratum 162001800 */
> +		smmu_pmu->options |= SMMU_PMCG_EVCNTR_RDONLY;
>   }
>   
>   static int smmu_pmu_probe(struct platform_device *pdev)
> @@ -834,7 +842,13 @@ static int smmu_pmu_probe(struct platform_device *pdev)
>   		return -EINVAL;
>   	}
>   
> -	smmu_pmu_get_acpi_options(smmu_pmu);
> +	if (dev->of_node)
> +		smmu_pmu_get_of_options(smmu_pmu);
> +	else
> +		smmu_pmu_get_acpi_options(smmu_pmu);
> +
> +	if (smmu_pmu->options)
> +		dev_notice(dev, "option mask 0x%x\n", smmu_pmu->options);
>   
>   	/* Pick one CPU to be the preferred one to use */
>   	smmu_pmu->on_cpu = raw_smp_processor_id();
> @@ -884,10 +898,17 @@ static void smmu_pmu_shutdown(struct platform_device *pdev)
>   	smmu_pmu_disable(&smmu_pmu->pmu);
>   }
>   
> +static const struct of_device_id arm_smmu_pmu_match[] = {
> +	{ .compatible = "arm,smmu-v3-pmcg" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, arm_smmu_pmu_match);
> +
>   static struct platform_driver smmu_pmu_driver = {
>   	.driver = {
>   		.name = "arm-smmu-v3-pmcg",
>   		.suppress_bind_attrs = true,
> +		.of_match_table = of_match_ptr(arm_smmu_pmu_match),
>   	},
>   	.probe = smmu_pmu_probe,
>   	.remove = smmu_pmu_remove,
>