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From:   Manish Narani <manish.narani@xilinx.com>
To:     <michal.simek@xilinx.com>, <adrian.hunter@intel.com>,
        <ulf.hansson@linaro.org>
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        <git@xilinx.com>, Manish Narani <manish.narani@xilinx.com>,
        Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Subject: [PATCH v2 3/3] mmc: sdhci-of-arasan: Issue DLL reset explicitly
Date:   Mon, 16 Nov 2020 14:02:45 +0530
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In the current implementation DLL reset will be issued for
each ITAP and OTAP setting inside ATF, this is creating issues
in some scenarios and this sequence is not inline with the TRM.
To fix the issue, DLL reset should be removed from the ATF and
host driver will request it explicitly.
This patch update host driver to explicitly request for DLL reset
before ITAP (assert DLL) and after OTAP (release DLL) settings.

Fixes: a5c8b2ae2e51 ("mmc: sdhci-of-arasan: Add support for ZynqMP Platform Tap Delays Setup")
Signed-off-by: Sai Krishna Potthuri <lakshmi.sai.krishna.potthuri@xilinx.com>
Signed-off-by: Manish Narani <manish.narani@xilinx.com>
---
 drivers/mmc/host/sdhci-of-arasan.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 3ec5ecad637c..d25a4b50c2f3 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -635,6 +635,9 @@ static int sdhci_zynqmp_sdcardclk_set_phase(struct clk_hw *hw, int degrees)
 	if (ret)
 		pr_err("Error setting Output Tap Delay\n");
 
+	/* Release DLL Reset */
+	zynqmp_pm_sd_dll_reset(node_id, PM_DLL_RESET_RELEASE);
+
 	return ret;
 }
 
@@ -669,6 +672,9 @@ static int sdhci_zynqmp_sampleclk_set_phase(struct clk_hw *hw, int degrees)
 	if (host->version < SDHCI_SPEC_300)
 		return 0;
 
+	/* Assert DLL Reset */
+	zynqmp_pm_sd_dll_reset(node_id, PM_DLL_RESET_ASSERT);
+
 	switch (host->timing) {
 	case MMC_TIMING_MMC_HS:
 	case MMC_TIMING_SD_HS:
-- 
2.17.1