summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--drivers/bus/mhi/ep/internal.h3
-rw-r--r--drivers/bus/mhi/ep/main.c22
-rw-r--r--drivers/bus/mhi/ep/ring.c19
3 files changed, 40 insertions, 4 deletions
diff --git a/drivers/bus/mhi/ep/internal.h b/drivers/bus/mhi/ep/internal.h
index a2125fa5fe2f..8c5cf2b67951 100644
--- a/drivers/bus/mhi/ep/internal.h
+++ b/drivers/bus/mhi/ep/internal.h
@@ -126,6 +126,7 @@ struct mhi_ep_ring {
union mhi_ep_ring_ctx *ring_ctx;
struct mhi_ring_element *ring_cache;
enum mhi_ep_ring_type type;
+ struct delayed_work intmodt_work;
u64 rbase;
size_t rd_offset;
size_t wr_offset;
@@ -135,7 +136,9 @@ struct mhi_ep_ring {
u32 ch_id;
u32 er_index;
u32 irq_vector;
+ u32 intmodt;
bool started;
+ bool irq_pending;
};
struct mhi_ep_cmd {
diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index 517279600645..c759183943ed 100644
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -54,11 +54,27 @@ static int mhi_ep_send_event(struct mhi_ep_cntrl *mhi_cntrl, u32 ring_idx,
mutex_unlock(&mhi_cntrl->event_lock);
/*
- * Raise IRQ to host only if the BEI flag is not set in TRE. Host might
- * set this flag for interrupt moderation as per MHI protocol.
+ * As per the MHI specification, section 4.3, Interrupt moderation:
+ *
+ * 1. If BEI flag is not set, cancel any pending intmodt work if started
+ * for the event ring and raise IRQ immediately.
+ *
+ * 2. If both BEI and intmodt are set, and if no IRQ is pending for the
+ * same event ring, start the IRQ delayed work as per the value of
+ * intmodt. If previous IRQ is pending, then do nothing as the pending
+ * IRQ is enough for the host to process the current event ring element.
+ *
+ * 3. If BEI is set and intmodt is not set, no need to raise IRQ.
*/
- if (!bei)
+ if (!bei) {
+ if (READ_ONCE(ring->irq_pending))
+ cancel_delayed_work(&ring->intmodt_work);
+
mhi_cntrl->raise_irq(mhi_cntrl, ring->irq_vector);
+ } else if (ring->intmodt && !READ_ONCE(ring->irq_pending)) {
+ WRITE_ONCE(ring->irq_pending, true);
+ schedule_delayed_work(&ring->intmodt_work, msecs_to_jiffies(ring->intmodt));
+ }
return 0;
diff --git a/drivers/bus/mhi/ep/ring.c b/drivers/bus/mhi/ep/ring.c
index 115518ec76a4..a1071c13761b 100644
--- a/drivers/bus/mhi/ep/ring.c
+++ b/drivers/bus/mhi/ep/ring.c
@@ -157,6 +157,15 @@ void mhi_ep_ring_init(struct mhi_ep_ring *ring, enum mhi_ep_ring_type type, u32
}
}
+static void mhi_ep_raise_irq(struct work_struct *work)
+{
+ struct mhi_ep_ring *ring = container_of(work, struct mhi_ep_ring, intmodt_work.work);
+ struct mhi_ep_cntrl *mhi_cntrl = ring->mhi_cntrl;
+
+ mhi_cntrl->raise_irq(mhi_cntrl, ring->irq_vector);
+ WRITE_ONCE(ring->irq_pending, false);
+}
+
int mhi_ep_ring_start(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_ring *ring,
union mhi_ep_ring_ctx *ctx)
{
@@ -173,8 +182,13 @@ int mhi_ep_ring_start(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_ring *ring,
if (ring->type == RING_TYPE_CH)
ring->er_index = le32_to_cpu(ring->ring_ctx->ch.erindex);
- if (ring->type == RING_TYPE_ER)
+ if (ring->type == RING_TYPE_ER) {
ring->irq_vector = le32_to_cpu(ring->ring_ctx->ev.msivec);
+ ring->intmodt = FIELD_GET(EV_CTX_INTMODT_MASK,
+ le32_to_cpu(ring->ring_ctx->ev.intmod));
+
+ INIT_DELAYED_WORK(&ring->intmodt_work, mhi_ep_raise_irq);
+ }
/* During ring init, both rp and wp are equal */
memcpy_fromio(&val, (void __iomem *) &ring->ring_ctx->generic.rp, sizeof(u64));
@@ -201,6 +215,9 @@ int mhi_ep_ring_start(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_ring *ring,
void mhi_ep_ring_reset(struct mhi_ep_cntrl *mhi_cntrl, struct mhi_ep_ring *ring)
{
+ if (ring->type == RING_TYPE_ER)
+ cancel_delayed_work_sync(&ring->intmodt_work);
+
ring->started = false;
kfree(ring->ring_cache);
ring->ring_cache = NULL;