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authorMarc Zyngier <maz@kernel.org>2019-12-24 12:10:30 +0100
committerMarc Zyngier <maz@kernel.org>2020-01-22 15:22:20 +0100
commit0684c7046590dd1e8047e187aaf4c7910cc35bce (patch)
treec962428a16f4dde55c65af35f51f5d41721b44fb /drivers/irqchip/irq-gic-v3-its.c
parentirqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP (diff)
downloadlinux-0684c7046590dd1e8047e187aaf4c7910cc35bce.tar.xz
linux-0684c7046590dd1e8047e187aaf4c7910cc35bce.zip
irqchip/gic-v4.1: Don't use the VPE proxy if RVPEID is set
The infamous VPE proxy device isn't used with GICv4.1 because: - we can invalidate any LPI from the DirectLPI MMIO interface - the ITS and redistributors understand the life cycle of the doorbell, so we don't need to enable/disable it all the time So let's escape early from the proxy related functions. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com> Link: https://lore.kernel.org/r/20191224111055.11836-8-maz@kernel.org
Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its.c')
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c25
1 files changed, 24 insertions, 1 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index fbf4ca796b8a..9bc8adf7d51e 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -3212,7 +3212,7 @@ static const struct irq_domain_ops its_domain_ops = {
/*
* This is insane.
*
- * If a GICv4 doesn't implement Direct LPIs (which is extremely
+ * If a GICv4.0 doesn't implement Direct LPIs (which is extremely
* likely), the only way to perform an invalidate is to use a fake
* device to issue an INV command, implying that the LPI has first
* been mapped to some event on that device. Since this is not exactly
@@ -3220,9 +3220,20 @@ static const struct irq_domain_ops its_domain_ops = {
* only issue an UNMAP if we're short on available slots.
*
* Broken by design(tm).
+ *
+ * GICv4.1, on the other hand, mandates that we're able to invalidate
+ * by writing to a MMIO register. It doesn't implement the whole of
+ * DirectLPI, but that's good enough. And most of the time, we don't
+ * even have to invalidate anything, as the redistributor can be told
+ * whether to generate a doorbell or not (we thus leave it enabled,
+ * always).
*/
static void its_vpe_db_proxy_unmap_locked(struct its_vpe *vpe)
{
+ /* GICv4.1 doesn't use a proxy, so nothing to do here */
+ if (gic_rdists->has_rvpeid)
+ return;
+
/* Already unmapped? */
if (vpe->vpe_proxy_event == -1)
return;
@@ -3245,6 +3256,10 @@ static void its_vpe_db_proxy_unmap_locked(struct its_vpe *vpe)
static void its_vpe_db_proxy_unmap(struct its_vpe *vpe)
{
+ /* GICv4.1 doesn't use a proxy, so nothing to do here */
+ if (gic_rdists->has_rvpeid)
+ return;
+
if (!gic_rdists->has_direct_lpi) {
unsigned long flags;
@@ -3256,6 +3271,10 @@ static void its_vpe_db_proxy_unmap(struct its_vpe *vpe)
static void its_vpe_db_proxy_map_locked(struct its_vpe *vpe)
{
+ /* GICv4.1 doesn't use a proxy, so nothing to do here */
+ if (gic_rdists->has_rvpeid)
+ return;
+
/* Already mapped? */
if (vpe->vpe_proxy_event != -1)
return;
@@ -3278,6 +3297,10 @@ static void its_vpe_db_proxy_move(struct its_vpe *vpe, int from, int to)
unsigned long flags;
struct its_collection *target_col;
+ /* GICv4.1 doesn't use a proxy, so nothing to do here */
+ if (gic_rdists->has_rvpeid)
+ return;
+
if (gic_rdists->has_direct_lpi) {
void __iomem *rdbase;