Re: [PATCH RESEND 2/2] scsi: ufs: Update L4 attributes on manual hibern8 exit in Cadence UFS.

From: Vignesh Raghavendra
Date: Thu Nov 21 2019 - 05:56:23 EST




On 20/11/19 9:50 PM, Alim Akhtar wrote:
> Hi Sheebab
>
> On Tue, Nov 19, 2019 at 12:38 PM sheebab <sheebab@xxxxxxxxxxx> wrote:
>>
>> Backup L4 attributes duirng manual hibern8 entry
>> and restore the L4 attributes on manual hibern8 exit as per JESD220C.
>>
> Can you point me to the relevant section on the spec?
>

Per JESD 220C 9.4 UniPro/UFS Control Interface (Control Plane):

"NOTE After exit from Hibernate all UniPro Transport Layer attributes (including L4 T_PeerDeviceID,

L4 T_PeerCPortID, L4 T_ConnectionState, etc.) will be reset to their reset values. All required attributes

must be restored properly on both ends before communication can resume."

But its not clear whether SW needs to restore these attributes or hardware

Regards
Vignesh

>> Signed-off-by: sheebab <sheebab@xxxxxxxxxxx>
>> ---
>> drivers/scsi/ufs/cdns-pltfrm.c | 97 +++++++++++++++++++++++++++++++++++++++++-
>> 1 file changed, 95 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/cdns-pltfrm.c b/drivers/scsi/ufs/cdns-pltfrm.c
>> index adbbd60..5510567 100644
>> --- a/drivers/scsi/ufs/cdns-pltfrm.c
>> +++ b/drivers/scsi/ufs/cdns-pltfrm.c
>> @@ -19,6 +19,14 @@
>>
>> #define CDNS_UFS_REG_HCLKDIV 0xFC
>> #define CDNS_UFS_REG_PHY_XCFGD1 0x113C
>> +#define CDNS_UFS_MAX 12
>> +
>> +struct cdns_ufs_host {
>> + /**
>> + * cdns_ufs_dme_attr_val - for storing L4 attributes
>> + */
>> + u32 cdns_ufs_dme_attr_val[CDNS_UFS_MAX];
>> +};
>>
>> /**
>> * cdns_ufs_enable_intr - enable interrupts
>> @@ -47,6 +55,77 @@ static void cdns_ufs_disable_intr(struct ufs_hba *hba, u32 intrs)
>> }
>>
>> /**
>> + * cdns_ufs_get_l4_attr - get L4 attributes on local side
>> + * @hba: per adapter instance
>> + *
>> + */
>> +static void cdns_ufs_get_l4_attr(struct ufs_hba *hba)
>> +{
>> + struct cdns_ufs_host *host = ufshcd_get_variant(hba);
>> +
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_PEERDEVICEID),
>> + &host->cdns_ufs_dme_attr_val[0]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_PEERCPORTID),
>> + &host->cdns_ufs_dme_attr_val[1]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_TRAFFICCLASS),
>> + &host->cdns_ufs_dme_attr_val[2]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_PROTOCOLID),
>> + &host->cdns_ufs_dme_attr_val[3]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_CPORTFLAGS),
>> + &host->cdns_ufs_dme_attr_val[4]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_TXTOKENVALUE),
>> + &host->cdns_ufs_dme_attr_val[5]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_RXTOKENVALUE),
>> + &host->cdns_ufs_dme_attr_val[6]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_LOCALBUFFERSPACE),
>> + &host->cdns_ufs_dme_attr_val[7]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_PEERBUFFERSPACE),
>> + &host->cdns_ufs_dme_attr_val[8]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_CREDITSTOSEND),
>> + &host->cdns_ufs_dme_attr_val[9]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_CPORTMODE),
>> + &host->cdns_ufs_dme_attr_val[10]);
>> + ufshcd_dme_get(hba, UIC_ARG_MIB(T_CONNECTIONSTATE),
>> + &host->cdns_ufs_dme_attr_val[11]);
>> +}
>> +
>> +/**
>> + * cdns_ufs_set_l4_attr - set L4 attributes on local side
>> + * @hba: per adapter instance
>> + *
>> + */
>> +static void cdns_ufs_set_l4_attr(struct ufs_hba *hba)
>> +{
>> + struct cdns_ufs_host *host = ufshcd_get_variant(hba);
>> +
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_CONNECTIONSTATE), 0);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_PEERDEVICEID),
>> + host->cdns_ufs_dme_attr_val[0]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_PEERCPORTID),
>> + host->cdns_ufs_dme_attr_val[1]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_TRAFFICCLASS),
>> + host->cdns_ufs_dme_attr_val[2]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_PROTOCOLID),
>> + host->cdns_ufs_dme_attr_val[3]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_CPORTFLAGS),
>> + host->cdns_ufs_dme_attr_val[4]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_TXTOKENVALUE),
>> + host->cdns_ufs_dme_attr_val[5]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_RXTOKENVALUE),
>> + host->cdns_ufs_dme_attr_val[6]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_LOCALBUFFERSPACE),
>> + host->cdns_ufs_dme_attr_val[7]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_PEERBUFFERSPACE),
>> + host->cdns_ufs_dme_attr_val[8]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_CREDITSTOSEND),
>> + host->cdns_ufs_dme_attr_val[9]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_CPORTMODE),
>> + host->cdns_ufs_dme_attr_val[10]);
>> + ufshcd_dme_set(hba, UIC_ARG_MIB(T_CONNECTIONSTATE),
>> + host->cdns_ufs_dme_attr_val[11]);
>> +}
>> +
>> +/**
>> * Sets HCLKDIV register value based on the core_clk
>> * @hba: host controller instance
>> *
>> @@ -134,6 +213,7 @@ static void cdns_ufs_hibern8_notify(struct ufs_hba *hba, enum uic_cmd_dme cmd,
>> * before manual hibernate entry.
>> */
>> cdns_ufs_enable_intr(hba, UFSHCD_UIC_HIBERN8_MASK);
>> + cdns_ufs_get_l4_attr(hba);
>> }
>> if (status == POST_CHANGE && cmd == UIC_CMD_DME_HIBER_EXIT) {
>> /**
>> @@ -141,6 +221,7 @@ static void cdns_ufs_hibern8_notify(struct ufs_hba *hba, enum uic_cmd_dme cmd,
>> * after manual hibern8 exit.
>> */
>> cdns_ufs_disable_intr(hba, UFSHCD_UIC_HIBERN8_MASK);
>> + cdns_ufs_set_l4_attr(hba);
>> }
>> }
>>
>> @@ -245,15 +326,27 @@ static int cdns_ufs_pltfrm_probe(struct platform_device *pdev)
>> const struct of_device_id *of_id;
>> struct ufs_hba_variant_ops *vops;
>> struct device *dev = &pdev->dev;
>> + struct cdns_ufs_host *host;
>> + struct ufs_hba *hba;
>>
>> of_id = of_match_node(cdns_ufs_of_match, dev->of_node);
>> vops = (struct ufs_hba_variant_ops *)of_id->data;
>>
>> /* Perform generic probe */
>> err = ufshcd_pltfrm_init(pdev, vops);
>> - if (err)
>> + if (err) {
>> dev_err(dev, "ufshcd_pltfrm_init() failed %d\n", err);
>> -
>> + goto out;
>> + }
>> + host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
>> + if (!host) {
>> + err = -ENOMEM;
>> + dev_err(dev, "%s: no memory for cdns host\n", __func__);
>> + goto out;
>> + }
>> + hba = platform_get_drvdata(pdev);
>> + ufshcd_set_variant(hba, host);
>> +out:
>> return err;
>> }
>>
>> --
>> 2.7.4
>>
>
>

--
Regards
Vignesh