2020-11-16 06:18:34

by Manish Narani

Subject: [PATCH 0/2] Bug Fixes to Tap Delay code in SDHCI Arasan driver

This patch set consists a couple of minor bug fixes for SDHCI Arasan
driver. The fixes are for tap delay programming where in some cases
tuning is failing for some of the SD cards.

Manish Narani (2):
mmc: sdhci-of-arasan: Use Mask writes for Tap delays
mmc: sdhci-of-arasan: Issue DLL reset explicitly

drivers/mmc/host/sdhci-of-arasan.c | 11 +++++++++++
1 file changed, 11 insertions(+)

--
2.17.1

2020-11-16 06:21:35

by Manish Narani

Subject: [PATCH 2/2] mmc: sdhci-of-arasan: Issue DLL reset explicitly

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 <[email protected]>
Signed-off-by: Manish Narani <[email protected]>
---
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..e066d8f51954 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");

+ eemi_ops->ioctl(node_id, IOCTL_SD_DLL_RESET,
+ PM_DLL_RESET_RELEASE, 0, NULL);
+
return ret;
}

@@ -794,6 +797,9 @@ static int sdhci_versal_sampleclk_set_phase(struct clk_hw *hw, int degrees)
if (host->version < SDHCI_SPEC_300)
return 0;

+ eemi_ops->ioctl(node_id, IOCTL_SD_DLL_RESET,
+ PM_DLL_RESET_ASSERT, 0, NULL);
+
switch (host->timing) {
case MMC_TIMING_MMC_HS:
case MMC_TIMING_SD_HS:
--
2.17.1

2020-11-16 07:15:41

by Michal Simek

Subject: Re: [PATCH 2/2] mmc: sdhci-of-arasan: Issue DLL reset explicitly

On 16. 11. 20 7:15, Manish Narani wrote:
> 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 <[email protected]>
> Signed-off-by: Manish Narani <[email protected]>
> ---
> 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..e066d8f51954 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");
>
> + eemi_ops->ioctl(node_id, IOCTL_SD_DLL_RESET,
> + PM_DLL_RESET_RELEASE, 0, NULL);
> +
> return ret;
> }
>
> @@ -794,6 +797,9 @@ static int sdhci_versal_sampleclk_set_phase(struct clk_hw *hw, int degrees)
> if (host->version < SDHCI_SPEC_300)
> return 0;
>
> + eemi_ops->ioctl(node_id, IOCTL_SD_DLL_RESET,
> + PM_DLL_RESET_ASSERT, 0, NULL);
> +
> switch (host->timing) {
> case MMC_TIMING_MMC_HS:
> case MMC_TIMING_SD_HS:
>

this won't apply. It needs to be fixed.

Thanks,
Michal