[PATCH 12/19] thunderbolt: Add ring_configure to tb_nhi_ops

[Sven Peter]

The Apple NHI has to configure and enable each ring with a single write
and uses a separate register range for the receive ring PDF masks. Add
an optional tb_nhi_ops hook for it which falls back to the standard USB4
NHI method when it is not set.

Signed-off-by: Sven Peter <sven at kernel.org>
---
 drivers/thunderbolt/nhi.c | 55 ++++++++++++++++++++++++++++++-----------------
 drivers/thunderbolt/nhi.h |  4 ++++
 2 files changed, 39 insertions(+), 20 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 3cb69deec63e..696da52abff6 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -239,6 +239,31 @@ static void ring_iowrite32options(struct tb_ring *ring, u32 value, u32 offset)
 	iowrite32(value, ring_options_base(ring) + offset);
 }
 
+static void ring_configure(struct tb_ring *ring, u32 flags, u32 e2e_flags)
+{
+	if (ring->is_tx)
+		ring_iowrite32options(ring, 0, 4);
+	else
+		ring_iowrite32options(ring, ring->sof_mask << 16 | ring->eof_mask, 4);
+
+	ring_iowrite32options(ring, flags, 0);
+
+	/*
+	 * Now that the ring valid bit is set we can configure E2E if
+	 * enabled for the ring.
+	 */
+	if (e2e_flags)
+		ring_iowrite32options(ring, flags | e2e_flags, 0);
+}
+
+static void nhi_ring_configure(struct tb_ring *ring, u32 flags, u32 e2e_flags)
+{
+	if (ring->nhi->ops->ring_configure)
+		ring->nhi->ops->ring_configure(ring, flags, e2e_flags);
+	else
+		ring_configure(ring, flags, e2e_flags);
+}
+
 static bool ring_full(struct tb_ring *ring)
 {
 	return ((ring->head + 1) % ring->size) == ring->tail;
@@ -694,6 +719,7 @@ EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);
  */
 void tb_ring_start(struct tb_ring *ring)
 {
+	u32 e2e_flags = 0;
 	u16 frame_size;
 	u32 flags;
 
@@ -717,30 +743,13 @@ void tb_ring_start(struct tb_ring *ring)
 		flags = RING_FLAG_ENABLE | RING_FLAG_RAW;
 	}
 
-	ring_iowrite64desc(ring, ring->descriptors_dma, 0);
-	if (ring->is_tx) {
-		ring_iowrite32desc(ring, ring->size, 12);
-		ring_iowrite32options(ring, 0, 4);
-		ring_iowrite32options(ring, flags, 0);
-	} else {
-		u32 sof_eof_mask = ring->sof_mask << 16 | ring->eof_mask;
-
-		ring_iowrite32desc(ring, (frame_size << 16) | ring->size, 12);
-		ring_iowrite32options(ring, sof_eof_mask, 4);
-		ring_iowrite32options(ring, flags, 0);
-	}
-
-	/*
-	 * Now that the ring valid bit is set we can configure E2E if
-	 * enabled for the ring.
-	 */
 	if (ring->flags & RING_FLAG_E2E) {
 		if (!ring->is_tx) {
 			u32 hop;
 
 			hop = ring->e2e_tx_hop << REG_RX_OPTIONS_E2E_HOP_SHIFT;
 			hop &= REG_RX_OPTIONS_E2E_HOP_MASK;
-			flags |= hop;
+			e2e_flags |= hop;
 
 			dev_dbg(ring->nhi->dev,
 				"enabling E2E for %s %d with TX HopID %d\n",
@@ -750,10 +759,16 @@ void tb_ring_start(struct tb_ring *ring)
 				RING_TYPE(ring), ring->hop);
 		}
 
-		flags |= RING_FLAG_E2E_FLOW_CONTROL;
-		ring_iowrite32options(ring, flags, 0);
+		e2e_flags |= RING_FLAG_E2E_FLOW_CONTROL;
 	}
 
+	ring_iowrite64desc(ring, ring->descriptors_dma, 0);
+	if (ring->is_tx)
+		ring_iowrite32desc(ring, ring->size, 12);
+	else
+		ring_iowrite32desc(ring, (frame_size << 16) | ring->size, 12);
+	nhi_ring_configure(ring, flags, e2e_flags);
+
 	if (!(ring->flags & RING_FLAG_NO_INTERRUPT))
 		nhi_ring_interrupt_active(ring, true);
 	ring->running = true;
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
index 5f70d7ddc2e2..670b48efeec5 100644
--- a/drivers/thunderbolt/nhi.h
+++ b/drivers/thunderbolt/nhi.h
@@ -76,6 +76,9 @@ struct tb_nhi_ring_layout {
  * @ring_interrupt_mask: NHI specific hook to mask/unmask the interrupt of a
  *			 single ring. If not set the standard USB4 NHI
  *			 registers are used.
+ * @ring_configure: NHI specific hook to program the ring options registers
+ *		    and enable the ring with the given flags. If not set
+ *		    the standard USB4 NHI registers are used.
  * @is_present: Whether the device is currently present on the parent bus
  * @init_interrupts: NHI specific interrupt initialization hook
  * @reset_interface: Resets the host interface
@@ -93,6 +96,7 @@ struct tb_nhi_ops {
 	void (*release_ring_irq)(struct tb_ring *ring);
 	void (*ring_interrupt_active)(struct tb_ring *ring, bool active);
 	void (*ring_interrupt_mask)(struct tb_ring *ring, bool mask);
+	void (*ring_configure)(struct tb_ring *ring, u32 flags, u32 e2e_flags);
 	bool (*is_present)(struct tb_nhi *nhi);
 	int (*init_interrupts)(struct tb_nhi *nhi);
 	void (*reset_interface)(struct tb_nhi *nhi);

-- 
2.55.0