From 8e9f25a290ae0016353c9ea13314c95fb3207812 Mon Sep 17 00:00:00 2001 From: Elad Nachman Date: Thu, 22 Feb 2024 22:09:30 +0200 Subject: mmc: sdhci-xenon: fix PHY init clock stability Each time SD/mmc phy is initialized, at times, in some of the attempts, phy fails to completes its initialization which results into timeout error. Per the HW spec, it is a pre-requisite to ensure a stable SD clock before a phy initialization is attempted. Fixes: 06c8b667ff5b ("mmc: sdhci-xenon: Add support to PHYs of Marvell Xenon SDHC") Acked-by: Adrian Hunter Cc: stable@vger.kernel.org Signed-off-by: Elad Nachman Link: https://lore.kernel.org/r/20240222200930.1277665-1-enachman@marvell.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-xenon-phy.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'drivers/mmc') diff --git a/drivers/mmc/host/sdhci-xenon-phy.c b/drivers/mmc/host/sdhci-xenon-phy.c index 8cf3a375de65..c3096230a969 100644 --- a/drivers/mmc/host/sdhci-xenon-phy.c +++ b/drivers/mmc/host/sdhci-xenon-phy.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include "sdhci-pltfm.h" @@ -216,6 +217,19 @@ static int xenon_alloc_emmc_phy(struct sdhci_host *host) return 0; } +static int xenon_check_stability_internal_clk(struct sdhci_host *host) +{ + u32 reg; + int err; + + err = read_poll_timeout(sdhci_readw, reg, reg & SDHCI_CLOCK_INT_STABLE, + 1100, 20000, false, host, SDHCI_CLOCK_CONTROL); + if (err) + dev_err(mmc_dev(host->mmc), "phy_init: Internal clock never stabilized.\n"); + + return err; +} + /* * eMMC 5.0/5.1 PHY init/re-init. * eMMC PHY init should be executed after: @@ -232,6 +246,11 @@ static int xenon_emmc_phy_init(struct sdhci_host *host) struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host); struct xenon_emmc_phy_regs *phy_regs = priv->emmc_phy_regs; + int ret = xenon_check_stability_internal_clk(host); + + if (ret) + return ret; + reg = sdhci_readl(host, phy_regs->timing_adj); reg |= XENON_PHY_INITIALIZAION; sdhci_writel(host, reg, phy_regs->timing_adj); -- cgit