[PATCH 5.4 372/434] can: xilinx_can: Fix missing Rx can packets on CANFD2.0

[Greg Kroah-Hartman]

From: Srinivas Neeli <srinivas.neeli@xxxxxxxxxx>

commit 9ab79b06ddf3cdf6484d60b3e5fe113e733145c8 upstream.

CANFD2.0 core uses BRAM for storing acceptance filter ID(AFID) and MASK
(AFMASK)registers. So by default AFID and AFMASK registers contain random
data. Due to random data, we are not able to receive all CAN ids.

Initializing AFID and AFMASK registers with Zero before enabling
acceptance filter to receive all packets irrespective of ID and Mask.

Fixes: 0db9071353a0 ("can: xilinx: add can 2.0 support")
Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
Signed-off-by: Srinivas Neeli <srinivas.neeli@xxxxxxxxxx>
Reviewed-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xxxxxxxxxx>
Cc: linux-stable <stable@xxxxxxxxxxxxxxx> # >= v5.0
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/can/xilinx_can.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -60,6 +60,8 @@ enum xcan_reg {
 	XCAN_TXMSG_BASE_OFFSET	= 0x0100, /* TX Message Space */
 	XCAN_RXMSG_BASE_OFFSET	= 0x1100, /* RX Message Space */
 	XCAN_RXMSG_2_BASE_OFFSET	= 0x2100, /* RX Message Space */
+	XCAN_AFR_2_MASK_OFFSET	= 0x0A00, /* Acceptance Filter MASK */
+	XCAN_AFR_2_ID_OFFSET	= 0x0A04, /* Acceptance Filter ID */
 };
 
 #define XCAN_FRAME_ID_OFFSET(frame_base)	((frame_base) + 0x00)
@@ -1803,6 +1805,11 @@ static int xcan_probe(struct platform_de
 
 	pm_runtime_put(&pdev->dev);
 
+	if (priv->devtype.flags & XCAN_FLAG_CANFD_2) {
+		priv->write_reg(priv, XCAN_AFR_2_ID_OFFSET, 0x00000000);
+		priv->write_reg(priv, XCAN_AFR_2_MASK_OFFSET, 0x00000000);
+	}
+
 	netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx buffers: actual %d, using %d\n",
 		   priv->reg_base, ndev->irq, priv->can.clock.freq,
 		   hw_tx_max, priv->tx_max);