Re: [PATCH v2 06/36] irqchip/gic-v3-its: Kill its->device_ids and use TYPER copy instead

[Zenghui Yu]

Hi Marc,

On 2019/10/27 22:42, Marc Zyngier wrote:
> Now that we have a copy of TYPER in the ITS structure, rely on this
> to provide the same service as its->device_ids, which gets axed.
> Errata workarounds are now updating the cached fields instead of
> requiring a separate field in the ITS structure.
>
> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>

Reviewed-by: Zenghui Yu <yuzenghui@xxxxxxxxxx>

> ---
>   drivers/irqchip/irq-gic-v3-its.c   | 24 +++++++++++++-----------
>   include/linux/irqchip/arm-gic-v3.h |  2 +-
>   2 files changed, 14 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 3b046181ddfc..6c91c7feadf3 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -109,7 +109,6 @@ struct its_node {
>   	struct list_head	its_device_list;
>   	u64			flags;
>   	unsigned long		list_nr;
> -	u32			device_ids;
>   	int			numa_node;
>   	unsigned int		msi_domain_flags;
>   	u32			pre_its_base; /* for Socionext Synquacer */
> @@ -117,6 +116,7 @@ struct its_node {
>   };
>   
>   #define is_v4(its)		(!!((its)->typer & GITS_TYPER_VLPIS))
> +#define device_ids(its)		(FIELD_GET(GITS_TYPER_DEVBITS, (its)->typer) + 1)
>   
>   #define ITS_ITT_ALIGN		SZ_256
>   
> @@ -1938,9 +1938,9 @@ static bool its_parse_indirect_baser(struct its_node *its,
>   	if (new_order >= MAX_ORDER) {
>   		new_order = MAX_ORDER - 1;
>   		ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
> -		pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
> +		pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n",
>   			&its->phys_base, its_base_type_string[type],
> -			its->device_ids, ids);
> +			device_ids(its), ids);

But this pr_warn() looks a bit odd. The table type is chosen from
its_base_type_string[], but ids is always Devbits (+1)?


Thanks,
Zenghui