Add bridged amplifiers to cs42l43

Merge series from Charles Keepax <[email protected]>:

In some cs42l43 systems a couple of cs35l56 amplifiers are attached
to the cs42l43's SPI and I2S. On Windows the cs42l43 is controlled
by a SDCA class driver and these two amplifiers are controlled by
firmware running on the cs42l43. However, under Linux the decision
was made to interact with the cs42l43 directly, affording the user
greater control over the audio system. However, this has resulted
in an issue where these two bridged cs35l56 amplifiers are not
populated in ACPI and must be added manually. There is at least an
SDCA extension unit DT entry we can key off.

The process of adding this is handled using a software node, firstly the
ability to add native chip selects to software nodes must be added.
Secondly, an additional flag for naming the SPI devices is added this
allows the machine driver to key to the correct amplifier. Then finally,
the cs42l43 SPI driver adds the two amplifiers directly onto its SPI
bus.

An additional series will follow soon to add the audio machine driver
parts (in the sof-sdw driver), however that is fairly orthogonal to
this part of the process, getting the actual amplifiers registered.

1 files changed, 61 insertions, 21 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 0d7177083708..1a12b732818e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2630,7 +2630,22 @@ process_next:
 	return failure ? budget : (int)total_rx_packets;
 }
 
-static inline u32 i40e_buildreg_itr(const int type, u16 itr)
+/**
+ * i40e_buildreg_itr - build a value for writing to I40E_PFINT_DYN_CTLN register
+ * @itr_idx: interrupt throttling index
+ * @interval: interrupt throttling interval value in usecs
+ * @force_swint: force software interrupt
+ *
+ * The function builds a value for I40E_PFINT_DYN_CTLN register that
+ * is used to update interrupt throttling interval for specified ITR index
+ * and optionally enforces a software interrupt. If the @itr_idx is equal
+ * to I40E_ITR_NONE then no interval change is applied and only @force_swint
+ * parameter is taken into account. If the interval change and enforced
+ * software interrupt are not requested then the built value just enables
+ * appropriate vector interrupt.
+ **/
+static u32 i40e_buildreg_itr(enum i40e_dyn_idx itr_idx, u16 interval,
+			     bool force_swint)
 {
 	u32 val;
 
@@ -2644,23 +2659,33 @@ static inline u32 i40e_buildreg_itr(const int type, u16 itr)
 	 * an event in the PBA anyway so we need to rely on the automask
 	 * to hold pending events for us until the interrupt is re-enabled
 	 *
-	 * The itr value is reported in microseconds, and the register
-	 * value is recorded in 2 microsecond units. For this reason we
-	 * only need to shift by the interval shift - 1 instead of the
-	 * full value.
+	 * We have to shift the given value as it is reported in microseconds
+	 * and the register value is recorded in 2 microsecond units.
 	 */
-	itr &= I40E_ITR_MASK;
+	interval >>= 1;
 
+	/* 1. Enable vector interrupt
+	 * 2. Update the interval for the specified ITR index
+	 *    (I40E_ITR_NONE in the register is used to indicate that
+	 *     no interval update is requested)
+	 */
 	val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
-	      (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
-	      (itr << (I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT - 1));
+	      FIELD_PREP(I40E_PFINT_DYN_CTLN_ITR_INDX_MASK, itr_idx) |
+	      FIELD_PREP(I40E_PFINT_DYN_CTLN_INTERVAL_MASK, interval);
+
+	/* 3. Enforce software interrupt trigger if requested
+	 *    (These software interrupts rate is limited by ITR2 that is
+	 *     set to 20K interrupts per second)
+	 */
+	if (force_swint)
+		val |= I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
+		       I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK |
+		       FIELD_PREP(I40E_PFINT_DYN_CTLN_SW_ITR_INDX_MASK,
+				  I40E_SW_ITR);
 
 	return val;
 }
 
-/* a small macro to shorten up some long lines */
-#define INTREG I40E_PFINT_DYN_CTLN
-
 /* The act of updating the ITR will cause it to immediately trigger. In order
  * to prevent this from throwing off adaptive update statistics we defer the
  * update so that it can only happen so often. So after either Tx or Rx are
@@ -2679,8 +2704,10 @@ static inline u32 i40e_buildreg_itr(const int type, u16 itr)
 static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
 					  struct i40e_q_vector *q_vector)
 {
+	enum i40e_dyn_idx itr_idx = I40E_ITR_NONE;
 	struct i40e_hw *hw = &vsi->back->hw;
-	u32 intval;
+	u16 interval = 0;
+	u32 itr_val;
 
 	/* If we don't have MSIX, then we only need to re-enable icr0 */
 	if (!test_bit(I40E_FLAG_MSIX_ENA, vsi->back->flags)) {
@@ -2702,8 +2729,8 @@ static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
 	 */
 	if (q_vector->rx.target_itr < q_vector->rx.current_itr) {
 		/* Rx ITR needs to be reduced, this is highest priority */
-		intval = i40e_buildreg_itr(I40E_RX_ITR,
-					   q_vector->rx.target_itr);
+		itr_idx = I40E_RX_ITR;
+		interval = q_vector->rx.target_itr;
 		q_vector->rx.current_itr = q_vector->rx.target_itr;
 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
 	} else if ((q_vector->tx.target_itr < q_vector->tx.current_itr) ||
@@ -2712,25 +2739,36 @@ static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
 		/* Tx ITR needs to be reduced, this is second priority
 		 * Tx ITR needs to be increased more than Rx, fourth priority
 		 */
-		intval = i40e_buildreg_itr(I40E_TX_ITR,
-					   q_vector->tx.target_itr);
+		itr_idx = I40E_TX_ITR;
+		interval = q_vector->tx.target_itr;
 		q_vector->tx.current_itr = q_vector->tx.target_itr;
 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
 	} else if (q_vector->rx.current_itr != q_vector->rx.target_itr) {
 		/* Rx ITR needs to be increased, third priority */
-		intval = i40e_buildreg_itr(I40E_RX_ITR,
-					   q_vector->rx.target_itr);
+		itr_idx = I40E_RX_ITR;
+		interval = q_vector->rx.target_itr;
 		q_vector->rx.current_itr = q_vector->rx.target_itr;
 		q_vector->itr_countdown = ITR_COUNTDOWN_START;
 	} else {
 		/* No ITR update, lowest priority */
-		intval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
 		if (q_vector->itr_countdown)
 			q_vector->itr_countdown--;
 	}
 
-	if (!test_bit(__I40E_VSI_DOWN, vsi->state))
-		wr32(hw, INTREG(q_vector->reg_idx), intval);
+	/* Do not update interrupt control register if VSI is down */
+	if (test_bit(__I40E_VSI_DOWN, vsi->state))
+		return;
+
+	/* Update ITR interval if necessary and enforce software interrupt
+	 * if we are exiting busy poll.
+	 */
+	if (q_vector->in_busy_poll) {
+		itr_val = i40e_buildreg_itr(itr_idx, interval, true);
+		q_vector->in_busy_poll = false;
+	} else {
+		itr_val = i40e_buildreg_itr(itr_idx, interval, false);
+	}
+	wr32(hw, I40E_PFINT_DYN_CTLN(q_vector->reg_idx), itr_val);
 }
 
 /**
@@ -2845,6 +2883,8 @@ tx_only:
 	 */
 	if (likely(napi_complete_done(napi, work_done)))
 		i40e_update_enable_itr(vsi, q_vector);
+	else
+		q_vector->in_busy_poll = true;
 
 	return min(work_done, budget - 1);
 }