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

Zenghui Yu
2019-10-31T06:33:43Z

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@kernel.org>

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>

> ---
> 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