[PATCH v3 11/32] irqchip/gic-v4.1: Add VPE residency callback

Marc Zyngier
2019-12-24T11:40:57Z

Making a VPE resident on GICv4.1 is pretty simple, as it is just a
single write to the local redistributor. We just need extra information
about which groups to enable, which the KVM code will have to provide.

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
drivers/irqchip/irq-gic-v3-its.c | 17 +++++++++++++++++
include/linux/irqchip/arm-gic-v3.h | 9 +++++++++
include/linux/irqchip/arm-gic-v4.h | 5 +++++
3 files changed, 31 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 0da6baa48153..49850297fe56 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -3625,12 +3625,29 @@ static void its_vpe_4_1_unmask_irq(struct irq_data *d)
its_vpe_4_1_send_inv(d);
}

+static void its_vpe_4_1_schedule(struct its_vpe *vpe,
+ struct its_cmd_info *info)
+{
+ void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
+ u64 val = 0;
+
+ /* Schedule the VPE */
+ val |= GICR_VPENDBASER_Valid;
+ val |= info->g0en ? GICR_VPENDBASER_4_1_VGRP0EN : 0;
+ val |= info->g1en ? GICR_VPENDBASER_4_1_VGRP1EN : 0;
+ val |= FIELD_PREP(GICR_VPENDBASER_4_1_VPEID, vpe->vpe_id);
+
+ gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
+}
+
static int its_vpe_4_1_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
{
+ struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
struct its_cmd_info *info = vcpu_info;

switch (info->cmd_type) {
case SCHEDULE_VPE:
+ its_vpe_4_1_schedule(vpe, info);
return 0;

case DESCHEDULE_VPE:
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 33519b7c96cf..1c91dede7663 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -329,6 +329,15 @@
#define GICR_VPENDBASER_IDAI (1ULL << 62)
#define GICR_VPENDBASER_Valid (1ULL << 63)

+/*
+ * GICv4.1 VPENDBASER, used for VPE residency. On top of these fields,
+ * also use the above Valid, PendingLast and Dirty.
+ */
+#define GICR_VPENDBASER_4_1_DB (1ULL << 62)
+#define GICR_VPENDBASER_4_1_VGRP0EN (1ULL << 59)
+#define GICR_VPENDBASER_4_1_VGRP1EN (1ULL << 58)
+#define GICR_VPENDBASER_4_1_VPEID GENMASK_ULL(15, 0)
+
/*
* ITS registers, offsets from ITS_base
*/
diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h
index 498e523085a7..d9c34968467a 100644
--- a/include/linux/irqchip/arm-gic-v4.h
+++ b/include/linux/irqchip/arm-gic-v4.h
@@ -100,6 +100,11 @@ struct its_cmd_info {
union {
struct its_vlpi_map *map;
u8 config;
+ bool req_db;
+ struct {
+ bool g0en;
+ bool g1en;
+ };
};
};

--
2.20.1