Re: [PATCH v7 07/15] irqchip: gicv3-its: platform-msi: scan MADT to create platform msi domain

[Matthias Brugger <mbrugger@suse.com>]

On 11/01/17 16:06, Hanjun Guo wrote:
> With the introduction of its_pmsi_init_one(), we can add some code
> on top for ACPI support of platform MSI.
>
> We are scanning the MADT table to get the ITS entry(ies), then use
> the information to create the platform msi domain for devices connect
> to it, just like the PCI MSI for ITS did.
>
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> Cc: Marc Zyngier <marc.zyngier@arm.com>
> Cc: Sinan Kaya <okaya@codeaurora.org>
> Cc: Tomasz Nowicki <tn@semihalf.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> ---
>  drivers/irqchip/irq-gic-v3-its-platform-msi.c | 36 +++++++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
>

Reviewed-by: Matthias Brugger <mbrugger@suse.com>

> diff --git a/drivers/irqchip/irq-gic-v3-its-platform-msi.c b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
> index 3d9efd1..ebe933e 100644
> --- a/drivers/irqchip/irq-gic-v3-its-platform-msi.c
> +++ b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
> @@ -103,6 +103,41 @@ static int __init its_pmsi_init_one(struct fwnode_handle *fwnode,
>  	return 0;
>  }
>
> +#ifdef CONFIG_ACPI
> +static int __init
> +its_pmsi_parse_madt(struct acpi_subtable_header *header,
> +			const unsigned long end)
> +{
> +	struct acpi_madt_generic_translator *its_entry;
> +	struct fwnode_handle *domain_handle;
> +	const char *node_name;
> +	int err = -ENXIO;
> +
> +	its_entry = (struct acpi_madt_generic_translator *)header;
> +	node_name = kasprintf(GFP_KERNEL, "ITS@0x%lx",
> +			      (long)its_entry->base_address);
> +	domain_handle = iort_find_domain_token(its_entry->translation_id);
> +	if (!domain_handle) {
> +		pr_err("%s: Unable to locate ITS domain handle\n", node_name);
> +		goto out;
> +	}
> +
> +	err = its_pmsi_init_one(domain_handle, node_name);
> +
> +out:
> +	kfree(node_name);
> +	return err;
> +}
> +
> +static void __init its_pmsi_acpi_init(void)
> +{
> +	acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
> +			      its_pmsi_parse_madt, 0);
> +}
> +#else
> +static inline void its_pmsi_acpi_init(void) { }
> +#endif
> +
>  static void __init its_pmsi_of_init(void)
>  {
>  	struct device_node *np;
> @@ -119,6 +154,7 @@ static void __init its_pmsi_of_init(void)
>  static int __init its_pmsi_init(void)
>  {
>  	its_pmsi_of_init();
> +	its_pmsi_acpi_init();
>  	return 0;
>  }
>  early_initcall(its_pmsi_init);
>