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authorMarc Zyngier <maz@kernel.org>2019-12-24 14:10:35 +0300
committerMarc Zyngier <maz@kernel.org>2020-01-22 17:22:20 +0300
commite64fab1a1477dbf0c355691914511612ba312932 (patch)
treeedb063dfb2c6fbcffccdbda9445f5da4048b2301 /drivers/irqchip/irq-gic-v3-its.c
parent91bf6395f7b8614a5a9934a0ae9c8b5312d77b29 (diff)
downloadlinux-e64fab1a1477dbf0c355691914511612ba312932.tar.xz
irqchip/gic-v4.1: Add VPE eviction callback
When descheduling a VPE, special care must be taken to tell the GIC about whether we want to receive a doorbell or not. This is a major improvement on GICv4.0, where the doorbell had to be separately enabled/disabled. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Link: https://lore.kernel.org/r/20191224111055.11836-13-maz@kernel.org
Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c53
1 files changed, 42 insertions, 11 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 3adc597e2a82..69b16e5da383 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2630,7 +2630,7 @@ static int __init allocate_lpi_tables(void)
return 0;
}
-static u64 its_clear_vpend_valid(void __iomem *vlpi_base)
+static u64 its_clear_vpend_valid(void __iomem *vlpi_base, u64 clr, u64 set)
{
u32 count = 1000000; /* 1s! */
bool clean;
@@ -2638,6 +2638,8 @@ static u64 its_clear_vpend_valid(void __iomem *vlpi_base)
val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
val &= ~GICR_VPENDBASER_Valid;
+ val &= ~clr;
+ val |= set;
gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
do {
@@ -2650,6 +2652,11 @@ static u64 its_clear_vpend_valid(void __iomem *vlpi_base)
}
} while (!clean && count);
+ if (unlikely(val & GICR_VPENDBASER_Dirty)) {
+ pr_err_ratelimited("ITS virtual pending table not cleaning\n");
+ val |= GICR_VPENDBASER_PendingLast;
+ }
+
return val;
}
@@ -2758,7 +2765,7 @@ static void its_cpu_init_lpis(void)
* ancient programming gets left in and has possibility of
* corrupting memory.
*/
- val = its_clear_vpend_valid(vlpi_base);
+ val = its_clear_vpend_valid(vlpi_base, 0, 0);
WARN_ON(val & GICR_VPENDBASER_Dirty);
}
@@ -3438,16 +3445,10 @@ static void its_vpe_deschedule(struct its_vpe *vpe)
void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
u64 val;
- val = its_clear_vpend_valid(vlpi_base);
+ val = its_clear_vpend_valid(vlpi_base, 0, 0);
- if (unlikely(val & GICR_VPENDBASER_Dirty)) {
- pr_err_ratelimited("ITS virtual pending table not cleaning\n");
- vpe->idai = false;
- vpe->pending_last = true;
- } else {
- vpe->idai = !!(val & GICR_VPENDBASER_IDAI);
- vpe->pending_last = !!(val & GICR_VPENDBASER_PendingLast);
- }
+ vpe->idai = !!(val & GICR_VPENDBASER_IDAI);
+ vpe->pending_last = !!(val & GICR_VPENDBASER_PendingLast);
}
static void its_vpe_invall(struct its_vpe *vpe)
@@ -3639,6 +3640,35 @@ static void its_vpe_4_1_schedule(struct its_vpe *vpe,
gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
}
+static void its_vpe_4_1_deschedule(struct its_vpe *vpe,
+ struct its_cmd_info *info)
+{
+ void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
+ u64 val;
+
+ if (info->req_db) {
+ /*
+ * vPE is going to block: make the vPE non-resident with
+ * PendingLast clear and DB set. The GIC guarantees that if
+ * we read-back PendingLast clear, then a doorbell will be
+ * delivered when an interrupt comes.
+ */
+ val = its_clear_vpend_valid(vlpi_base,
+ GICR_VPENDBASER_PendingLast,
+ GICR_VPENDBASER_4_1_DB);
+ vpe->pending_last = !!(val & GICR_VPENDBASER_PendingLast);
+ } else {
+ /*
+ * We're not blocking, so just make the vPE non-resident
+ * with PendingLast set, indicating that we'll be back.
+ */
+ val = its_clear_vpend_valid(vlpi_base,
+ 0,
+ GICR_VPENDBASER_PendingLast);
+ vpe->pending_last = true;
+ }
+}
+
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);
@@ -3650,6 +3680,7 @@ static int its_vpe_4_1_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
return 0;
case DESCHEDULE_VPE:
+ its_vpe_4_1_deschedule(vpe, info);
return 0;
case INVALL_VPE: