Re: [PATCH v2 16/36] irqchip/gic-v4.1: Add mask/unmask doorbell callbacks

Zenghui Yu
2019-11-01T11:23:54Z

Hi Marc,

On 2019/10/27 22:42, Marc Zyngier wrote:
> masking/unmasking doorbells on GICv4.1 relies on a new INVDB command,
> which broadcasts the invalidation to all RDs.
>
> Implement the new command as well as the masking callbacks, and plug
> the whole thing into the v4.1 VPE irqchip.
>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

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

> ---
> drivers/irqchip/irq-gic-v3-its.c | 60 ++++++++++++++++++++++++++++++
> include/linux/irqchip/arm-gic-v3.h | 3 +-
> 2 files changed, 62 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index dcc7227af5f1..3c34bef70bdd 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -309,6 +309,10 @@ struct its_cmd_desc {
> u16 seq_num;
> u16 its_list;
> } its_vmovp_cmd;
> +
> + struct {
> + struct its_vpe *vpe;
> + } its_invdb_cmd;
> };
> };
>
> @@ -750,6 +754,21 @@ static struct its_vpe *its_build_vmovp_cmd(struct its_node *its,
> return valid_vpe(its, desc->its_vmovp_cmd.vpe);
> }
>
> +static struct its_vpe *its_build_invdb_cmd(struct its_node *its,
> + struct its_cmd_block *cmd,
> + struct its_cmd_desc *desc)
> +{
> + if (WARN_ON(!is_v4_1(its)))
> + return NULL;
> +
> + its_encode_cmd(cmd, GITS_CMD_INVDB);
> + its_encode_vpeid(cmd, desc->its_invdb_cmd.vpe->vpe_id);
> +
> + its_fixup_cmd(cmd);
> +
> + return valid_vpe(its, desc->its_invdb_cmd.vpe);
> +}
> +
> static u64 its_cmd_ptr_to_offset(struct its_node *its,
> struct its_cmd_block *ptr)
> {
> @@ -1117,6 +1136,14 @@ static void its_send_vinvall(struct its_node *its, struct its_vpe *vpe)
> its_send_single_vcommand(its, its_build_vinvall_cmd, &desc);
> }
>
> +static void its_send_invdb(struct its_node *its, struct its_vpe *vpe)
> +{
> + struct its_cmd_desc desc;
> +
> + desc.its_invdb_cmd.vpe = vpe;
> + its_send_single_vcommand(its, its_build_invdb_cmd, &desc);
> +}
> +
> /*
> * irqchip functions - assumes MSI, mostly.
> */
> @@ -3408,6 +3435,37 @@ static struct irq_chip its_vpe_irq_chip = {
> .irq_set_vcpu_affinity = its_vpe_set_vcpu_affinity,
> };
>
> +static void its_vpe_4_1_send_inv(struct irq_data *d)
> +{
> + struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
> + struct its_node *its;
> +
> + /*
> + * GICv4.1 wants doorbells to be invalidated using the
> + * INVDB command in order to be broadcast to all RDs. Send
> + * it to the first valid ITS, and let the HW do its magic.
> + */
> + list_for_each_entry(its, &its_nodes, entry) {
> + if (!is_v4_1(its))
> + continue;
> +
> + its_send_invdb(its, vpe);
> + break;
> + }

Maybe use find_4_1_its() helper instead?

Thanks,
Zenghui

> +}
> +
> +static void its_vpe_4_1_mask_irq(struct irq_data *d)
> +{
> + lpi_write_config(d->parent_data, LPI_PROP_ENABLED, 0);
> + its_vpe_4_1_send_inv(d);
> +}
> +
> +static void its_vpe_4_1_unmask_irq(struct irq_data *d)
> +{
> + lpi_write_config(d->parent_data, 0, LPI_PROP_ENABLED);
> + its_vpe_4_1_send_inv(d);
> +}
> +
> static int its_vpe_4_1_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
> {
> struct its_cmd_info *info = vcpu_info;
> @@ -3429,6 +3487,8 @@ static int its_vpe_4_1_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
>
> static struct irq_chip its_vpe_4_1_irq_chip = {
> .name = "GICv4.1-vpe",
> + .irq_mask = its_vpe_4_1_mask_irq,
> + .irq_unmask = its_vpe_4_1_unmask_irq,
> .irq_eoi = irq_chip_eoi_parent,
> .irq_set_affinity = its_vpe_set_affinity,
> .irq_set_vcpu_affinity = its_vpe_4_1_set_vcpu_affinity,
> diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
> index f1d6de53e09b..8157737053e4 100644
> --- a/include/linux/irqchip/arm-gic-v3.h
> +++ b/include/linux/irqchip/arm-gic-v3.h
> @@ -484,8 +484,9 @@
> #define GITS_CMD_VMAPTI GITS_CMD_GICv4(GITS_CMD_MAPTI)
> #define GITS_CMD_VMOVI GITS_CMD_GICv4(GITS_CMD_MOVI)
> #define GITS_CMD_VSYNC GITS_CMD_GICv4(GITS_CMD_SYNC)
> -/* VMOVP is the odd one, as it doesn't have a physical counterpart */
> +/* VMOVP and INVDB are the odd ones, as they dont have a physical counterpart */
> #define GITS_CMD_VMOVP GITS_CMD_GICv4(2)
> +#define GITS_CMD_INVDB GITS_CMD_GICv4(0xe)
>
> /*
> * ITS error numbers
>