This is a note to let you know that I've just added the patch titled
mmc: sdhci-xenon: fix PHY init clock stability
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mmc-sdhci-xenon-fix-phy-init-clock-stability.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8e9f25a290ae0016353c9ea13314c95fb3207812 Mon Sep 17 00:00:00 2001
From: Elad Nachman <enachman@xxxxxxxxxxx>
Date: Thu, 22 Feb 2024 22:09:30 +0200
Subject: mmc: sdhci-xenon: fix PHY init clock stability
From: Elad Nachman <enachman@xxxxxxxxxxx>
commit 8e9f25a290ae0016353c9ea13314c95fb3207812 upstream.
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 <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Elad Nachman <enachman@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240222200930.1277665-1-enachman@xxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-xenon-phy.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
--- a/drivers/mmc/host/sdhci-xenon-phy.c
+++ b/drivers/mmc/host/sdhci-xenon-phy.c
@@ -11,6 +11,7 @@
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/ktime.h>
+#include <linux/iopoll.h>
#include <linux/of_address.h>
#include "sdhci-pltfm.h"
@@ -218,6 +219,19 @@ static int xenon_alloc_emmc_phy(struct s
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:
@@ -234,6 +248,11 @@ static int xenon_emmc_phy_init(struct sd
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);
Patches currently in stable-queue which might be from enachman@xxxxxxxxxxx are
queue-5.4/mmc-sdhci-xenon-fix-phy-init-clock-stability.patch
queue-5.4/mmc-sdhci-xenon-add-timeout-for-phy-init-complete.patch
