From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Asutosh Das (asd)" Subject: Re: [PATCH v1 7/9] scsi: ufs: add UFS power collapse support during hibern8 Date: Mon, 23 Jul 2018 08:37:04 +0530 Message-ID: <8607cabf-e6ae-0a53-2139-d2279d458a9c@codeaurora.org> References: <13f4fbc290b5e3cfea95f49d65ddb2bf99a15cdb.1530880007.git.asutoshd@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Subhash Jadavani Cc: cang@codeaurora.org, vivek.gautam@codeaurora.org, rnayak@codeaurora.org, vinholikatti@gmail.com, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, Venkat Gopalakrishnan , linux-kernel@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org On 7/21/2018 5:28 AM, Subhash Jadavani wrote: > On 2018-07-06 05:30, Asutosh Das wrote: >> From: Subhash Jadavani >> >> UFS host controller hardware may allow the host controller >> to be power collapsed when UFS link is hibern8 state, this >> change allows the UFS host controller to be power collapsed >> during hibern8. >> >> Signed-off-by: Subhash Jadavani >> Signed-off-by: Venkat Gopalakrishnan >> Signed-off-by: Can Guo >> Signed-off-by: Asutosh Das >> --- >>  drivers/scsi/ufs/ufshcd.c |  8 ++++++-- >>  drivers/scsi/ufs/ufshcd.h | 13 ++++++++++++- >>  2 files changed, 18 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c >> index 40d9c35..50588cf 100644 >> --- a/drivers/scsi/ufs/ufshcd.c >> +++ b/drivers/scsi/ufs/ufshcd.c >> @@ -7673,13 +7673,17 @@ static int ufshcd_vreg_set_hpm(struct ufs_hba >> *hba) >> >>  static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba) >>  { >> -    if (ufshcd_is_link_off(hba)) >> +    if (ufshcd_is_link_off(hba) || >> +        (ufshcd_is_link_hibern8(hba) >> +         && ufshcd_is_power_collapse_during_hibern8_allowed(hba))) >>          ufshcd_setup_hba_vreg(hba, false); > > I guess we have to handle the UFS host controller power collapse via > "power-domains" which would requires us to specify the "power-domains" > attribute under UFS controller's DT node and then linux core power > framework should automatically collapse the UFS controller post runtime > suspend. This also means we can't power collapse UFS controller > aggressively (as part of clock gating) but it should still be fine from > power point of view. > >>  } >> >>  static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba) >>  { >> -    if (ufshcd_is_link_off(hba)) >> +    if (ufshcd_is_link_off(hba) || >> +        (ufshcd_is_link_hibern8(hba) >> +         && ufshcd_is_power_collapse_during_hibern8_allowed(hba))) >>          ufshcd_setup_hba_vreg(hba, true); >>  } >> >> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h >> index f79a639..8c5f987 100644 >> --- a/drivers/scsi/ufs/ufshcd.h >> +++ b/drivers/scsi/ufs/ufshcd.h >> @@ -728,7 +728,12 @@ struct ufs_hba { >>       * to do background operation when it's active but it might degrade >>       * the performance of ongoing read/write operations. >>       */ >> -#define UFSHCD_CAP_KEEP_AUTO_BKOPS_ENABLED_EXCEPT_SUSPEND (1 << 5) >> +#define UFSHCD_CAP_KEEP_AUTO_BKOPS_ENABLED_EXCEPT_SUSPEND (1 << 6) >> +    /* >> +     * If host controller hardware can be power collapsed when UFS >> link is >> +     * in hibern8 then enable this cap. >> +     */ >> +#define UFSHCD_CAP_POWER_COLLAPSE_DURING_HIBERN8 (1 << 7) >> >>      struct devfreq *devfreq; >>      struct ufs_clk_scaling clk_scaling; >> @@ -764,6 +769,12 @@ static inline bool >> ufshcd_is_hibern8_on_idle_allowed(struct ufs_hba *hba) >>      return hba->caps & UFSHCD_CAP_HIBERN8_ENTER_ON_IDLE; >>  } >> >> +static inline bool ufshcd_is_power_collapse_during_hibern8_allowed( >> +                        struct ufs_hba *hba) >> +{ >> +    return !!(hba->caps & UFSHCD_CAP_POWER_COLLAPSE_DURING_HIBERN8); >> +} >> + >>  static inline bool ufshcd_is_intr_aggr_allowed(struct ufs_hba *hba) >>  { >>  /* DWC UFS Core has the Interrupt aggregation feature but is not >> detectable*/ > Thanks. I'll check the 'power-domains' part and get back with the changes. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project