diff mbox series

[net-next,v5,11/14] net: ethernet: oa_tc6: implement mac-phy interrupt

Message ID 20240726123907.566348-12-Parthiban.Veerasooran@microchip.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Add support for OPEN Alliance 10BASE-T1x MACPHY Serial Interface | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 42 this patch: 42
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: parthiban.veerasooran@microchip.com
netdev/build_clang success Errors and warnings before: 43 this patch: 43
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 43 this patch: 43
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 85 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Parthiban Veerasooran July 26, 2024, 12:39 p.m. UTC
The MAC-PHY interrupt is asserted when the following conditions are met.

Receive chunks available - This interrupt is asserted when the previous
data footer had no receive data chunks available and once the receive
data chunks become available for reading. On reception of the first data
header this interrupt will be deasserted.

Transmit chunk credits available - This interrupt is asserted when the
previous data footer indicated no transmit credits available and once the
transmit credits become available for transmitting transmit data chunks.
On reception of the first data header this interrupt will be deasserted.

Extended status event - This interrupt is asserted when the previous data
footer indicated no extended status and once the extended event become
available. In this case the host should read status #0 register to know
the corresponding error/event. On reception of the first data header this
interrupt will be deasserted.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
---
 drivers/net/ethernet/oa_tc6.c | 53 +++++++++++++++++++++++++++++++++--
 1 file changed, 51 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c
index 5cbb45735b26..7f684b542bb1 100644
--- a/drivers/net/ethernet/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6.c
@@ -127,6 +127,7 @@  struct oa_tc6 {
 	u16 tx_credits;
 	u8 rx_chunks_available;
 	bool rx_buf_overflow;
+	bool int_flag;
 };
 
 enum oa_tc6_header_type {
@@ -1052,6 +1053,14 @@  static int oa_tc6_try_spi_transfer(struct oa_tc6 *tc6)
 		if (tc6->rx_chunks_available)
 			spi_length = oa_tc6_prepare_spi_tx_buf_for_rx_chunks(tc6, spi_length);
 
+		if (tc6->int_flag) {
+			tc6->int_flag = false;
+			if (spi_length == 0) {
+				oa_tc6_add_empty_chunks_to_spi_buf(tc6, 1);
+				spi_length = OA_TC6_CHUNK_SIZE;
+			}
+		}
+
 		if (spi_length == 0)
 			break;
 
@@ -1087,8 +1096,10 @@  static int oa_tc6_spi_thread_handler(void *data)
 	int ret;
 
 	while (likely(!kthread_should_stop())) {
-		/* This kthread will be waken up if there is a tx skb */
-		wait_event_interruptible(tc6->spi_wq,
+		/* This kthread will be waken up if there is a tx skb or mac-phy
+		 * interrupt to perform spi transfer with tx chunks.
+		 */
+		wait_event_interruptible(tc6->spi_wq, tc6->int_flag ||
 					 !skb_queue_empty(&tc6->tx_skb_q) ||
 					 kthread_should_stop());
 
@@ -1123,6 +1134,24 @@  static int oa_tc6_update_buffer_status_from_register(struct oa_tc6 *tc6)
 	return 0;
 }
 
+static irqreturn_t oa_tc6_macphy_isr(int irq, void *data)
+{
+	struct oa_tc6 *tc6 = data;
+
+	/* MAC-PHY interrupt can occur for the following reasons.
+	 * - availability of tx credits if it was 0 before and not reported in
+	 *   the previous rx footer.
+	 * - availability of rx chunks if it was 0 before and not reported in
+	 *   the previous rx footer.
+	 * - extended status event not reported in the previous rx footer.
+	 */
+	tc6->int_flag = true;
+	/* Wake spi kthread to perform spi transfer */
+	wake_up_interruptible(&tc6->spi_wq);
+
+	return IRQ_HANDLED;
+}
+
 /**
  * oa_tc6_start_xmit - function for sending the tx skb which consists ethernet
  * frame.
@@ -1247,8 +1276,28 @@  struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev)
 
 	sched_set_fifo(tc6->spi_thread);
 
+	ret = devm_request_irq(&tc6->spi->dev, tc6->spi->irq, oa_tc6_macphy_isr,
+			       IRQF_TRIGGER_FALLING, dev_name(&tc6->spi->dev),
+			       tc6);
+	if (ret) {
+		dev_err(&tc6->spi->dev, "Failed to request macphy isr %d\n",
+			ret);
+		goto kthread_stop;
+	}
+
+	/* oa_tc6_sw_reset_macphy() function resets and clears the MAC-PHY reset
+	 * complete status. IRQ is also asserted on reset completion and it is
+	 * remain asserted until MAC-PHY receives a data chunk. So performing an
+	 * empty data chunk transmission will deassert the IRQ. Refer section
+	 * 7.7 and 9.2.8.8 in the OPEN Alliance specification for more details.
+	 */
+	tc6->int_flag = true;
+	wake_up_interruptible(&tc6->spi_wq);
+
 	return tc6;
 
+kthread_stop:
+	kthread_stop(tc6->spi_thread);
 phy_exit:
 	oa_tc6_phy_exit(tc6);
 	return NULL;