Commit 253761a0 authored by Clayton Rayment's avatar Clayton Rayment Committed by Jakub Kicinski
Browse files

net: xilinx: axiethernet: Enable dynamic MDIO MDC 



MDIO spec does not require an MDC at all times, only when MDIO
transactions are occurring. This patch allows the xilinx_axienet
driver to disable the MDC when not in use, and re-enable it when
needed. It also simplifies the driver by removing MDC disable
and enable in device reset sequence.

Signed-off-by: default avatarClayton Rayment <clayton.rayment@xilinx.com>
Signed-off-by: default avatarRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 6c3cbaa0

drivers/net/ethernet/xilinx/xilinx_axienet_main.c

+4 −17
Original line number Diff line number Diff line
@@ -1049,20 +1049,13 @@ static int axienet_open(struct net_device *ndev) 


	dev_dbg(&ndev->dev, "axienet_open()\n");



	/* Disable the MDIO interface till Axi Ethernet Reset is completed.

	 * When we do an Axi Ethernet reset, it resets the complete core

	 * including the MDIO. MDIO must be disabled before resetting

	 * and re-enabled afterwards.

	/* When we do an Axi Ethernet reset, it resets the complete core

	 * including the MDIO. MDIO must be disabled before resetting.

	 * Hold MDIO bus lock to avoid MDIO accesses during the reset.

	 */

	mutex_lock(&lp->mii_bus->mdio_lock);

	axienet_mdio_disable(lp);

	ret = axienet_device_reset(ndev);

	if (ret == 0)

		ret = axienet_mdio_enable(lp);

	mutex_unlock(&lp->mii_bus->mdio_lock);

	if (ret < 0)

		return ret;



	ret = phylink_of_phy_connect(lp->phylink, lp->dev->of_node, 0);

	if (ret) {
@@ -1156,9 +1149,7 @@ static int axienet_stop(struct net_device *ndev) 


	/* Do a reset to ensure DMA is really stopped */

	mutex_lock(&lp->mii_bus->mdio_lock);

	axienet_mdio_disable(lp);

	__axienet_device_reset(lp);

	axienet_mdio_enable(lp);

	mutex_unlock(&lp->mii_bus->mdio_lock);



	cancel_work_sync(&lp->dma_err_task);
@@ -1669,16 +1660,12 @@ static void axienet_dma_err_handler(struct work_struct *work) 


	axienet_setoptions(ndev, lp->options &

			   ~(XAE_OPTION_TXEN | XAE_OPTION_RXEN));

	/* Disable the MDIO interface till Axi Ethernet Reset is completed.

	 * When we do an Axi Ethernet reset, it resets the complete core

	 * including the MDIO. MDIO must be disabled before resetting

	 * and re-enabled afterwards.

	/* When we do an Axi Ethernet reset, it resets the complete core

	 * including the MDIO. MDIO must be disabled before resetting.

	 * Hold MDIO bus lock to avoid MDIO accesses during the reset.

	 */

	mutex_lock(&lp->mii_bus->mdio_lock);

	axienet_mdio_disable(lp);

	__axienet_device_reset(lp);

	axienet_mdio_enable(lp);

	mutex_unlock(&lp->mii_bus->mdio_lock);



	for (i = 0; i < lp->tx_bd_num; i++) {

drivers/net/ethernet/xilinx/xilinx_axienet_mdio.c

+21 −6
Original line number Diff line number Diff line
@@ -65,9 +65,13 @@ static int axienet_mdio_read(struct mii_bus *bus, int phy_id, int reg) 
	int ret;

	struct axienet_local *lp = bus->priv;



	axienet_mdio_mdc_enable(lp);



	ret = axienet_mdio_wait_until_ready(lp);

	if (ret < 0)

	if (ret < 0) {

		axienet_mdio_mdc_disable(lp);

		return ret;

	}



	axienet_iow(lp, XAE_MDIO_MCR_OFFSET,

		    (((phy_id << XAE_MDIO_MCR_PHYAD_SHIFT) &
@@ -78,14 +82,17 @@ static int axienet_mdio_read(struct mii_bus *bus, int phy_id, int reg) 
		     XAE_MDIO_MCR_OP_READ_MASK));



	ret = axienet_mdio_wait_until_ready(lp);

	if (ret < 0)

	if (ret < 0) {

		axienet_mdio_mdc_disable(lp);

		return ret;

	}



	rc = axienet_ior(lp, XAE_MDIO_MRD_OFFSET) & 0x0000FFFF;



	dev_dbg(lp->dev, "axienet_mdio_read(phy_id=%i, reg=%x) == %x\n",

		phy_id, reg, rc);



	axienet_mdio_mdc_disable(lp);

	return rc;

}
@@ -111,9 +118,13 @@ static int axienet_mdio_write(struct mii_bus *bus, int phy_id, int reg, 
	dev_dbg(lp->dev, "axienet_mdio_write(phy_id=%i, reg=%x, val=%x)\n",

		phy_id, reg, val);



	axienet_mdio_mdc_enable(lp);



	ret = axienet_mdio_wait_until_ready(lp);

	if (ret < 0)

	if (ret < 0) {

		axienet_mdio_mdc_disable(lp);

		return ret;

	}



	axienet_iow(lp, XAE_MDIO_MWD_OFFSET, (u32) val);

	axienet_iow(lp, XAE_MDIO_MCR_OFFSET,
@@ -125,8 +136,11 @@ static int axienet_mdio_write(struct mii_bus *bus, int phy_id, int reg, 
		     XAE_MDIO_MCR_OP_WRITE_MASK));



	ret = axienet_mdio_wait_until_ready(lp);

	if (ret < 0)

	if (ret < 0) {

		axienet_mdio_mdc_disable(lp);

		return ret;

	}

	axienet_mdio_mdc_disable(lp);

	return 0;

}
@@ -230,8 +244,8 @@ void axienet_mdio_disable(struct axienet_local *lp) 
 * Return:	0 on success, -ETIMEDOUT on a timeout, -ENOMEM when

 *		mdiobus_alloc (to allocate memory for mii bus structure) fails.

 *

 * Sets up the MDIO interface by initializing the MDIO clock and enabling the

 * MDIO interface in hardware. Register the MDIO interface.

 * Sets up the MDIO interface by initializing the MDIO clock.

 * Register the MDIO interface.

 **/

int axienet_mdio_setup(struct axienet_local *lp)

{
@@ -265,6 +279,7 @@ int axienet_mdio_setup(struct axienet_local *lp) 
		lp->mii_bus = NULL;

		return ret;

	}

	axienet_mdio_mdc_disable(lp);

	return 0;

}