From 235d8b663ab9e6cc13f8374abfffa559f50b57b6 Mon Sep 17 00:00:00 2001 From: Sean Anderson Date: Fri, 28 Jun 2024 16:55:38 -0400 Subject: [PATCH] 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: Sean Anderson Link: https://lore.kernel.org/r/20240628205540.3098010-4-sean.anderson@linux.dev Signed-off-by: Vinod Koul --- drivers/phy/xilinx/phy-zynqmp.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/drivers/phy/xilinx/phy-zynqmp.c b/drivers/phy/xilinx/phy-zynqmp.c index a1cf32024efb..4d697e11d8eb 100644 --- a/drivers/phy/xilinx/phy-zynqmp.c +++ b/drivers/phy/xilinx/phy-zynqmp.c @@ -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 = >r_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)