Commit 235d8b66 authored by Sean Anderson's avatar Sean Anderson Committed by Vinod Koul
Browse files

phy: zynqmp: Only wait for PLL lock "primary" instances 



For PCIe and DisplayPort, the phy instance represents the controller's
logical lane. Wait for the instance 0 phy's PLL to lock as other
instances will never lock. We do this in xpsgtr_wait_pll_lock so callers
don't have to determine the correct lane themselves.

The original comment is wrong about cumulative wait times. Since we are
just polling a bit, all subsequent waiters will finish immediately.

Signed-off-by: default avatarSean Anderson <sean.anderson@linux.dev>
Link: https://lore.kernel.org/r/20240628205540.3098010-4-sean.anderson@linux.dev


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 6959d236

drivers/phy/xilinx/phy-zynqmp.c

+21 −9
Original line number Diff line number Diff line
@@ -294,10 +294,30 @@ static int xpsgtr_wait_pll_lock(struct phy *phy) 
	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);

	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;

	unsigned int timeout = TIMEOUT_US;

	u8 protocol = gtr_phy->protocol;

	int ret;



	dev_dbg(gtr_dev->dev, "Waiting for PLL lock\n");



	/*

	 * For DP and PCIe, only the instance 0 PLL is used. Switch to that phy

	 * so we wait on the right PLL.

	 */

	if ((protocol == ICM_PROTOCOL_DP || protocol == ICM_PROTOCOL_PCIE) &&

	    gtr_phy->instance) {

		int i;



		for (i = 0; i < NUM_LANES; i++) {

			gtr_phy = &gtr_dev->phys[i];



			if (gtr_phy->protocol == protocol && !gtr_phy->instance)

				goto got_phy;

		}



		return -EBUSY;

	}



got_phy:

	while (1) {

		u32 reg = xpsgtr_read_phy(gtr_phy, L0_PLL_STATUS_READ_1);
@@ -625,15 +645,7 @@ static int xpsgtr_phy_power_on(struct phy *phy) 
	/* Skip initialization if not required. */

	if (!xpsgtr_phy_init_required(gtr_phy))

		return ret;

	/*

	 * Wait for the PLL to lock. For DP, only wait on DP0 to avoid

	 * cumulating waits for both lanes. The user is expected to initialize

	 * lane 0 last.

	 */

	if (gtr_phy->protocol != ICM_PROTOCOL_DP || !gtr_phy->instance)

		ret = xpsgtr_wait_pll_lock(phy);



	return ret;

	return xpsgtr_wait_pll_lock(phy);

}



static int xpsgtr_phy_configure(struct phy *phy, union phy_configure_opts *opts)