From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1E85134BC; Thu, 30 Nov 2023 07:25:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f1sVFBfc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A39BC433C7; Thu, 30 Nov 2023 07:25:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701329139; bh=3YX4RL0/1V4O8MWlDUyKMhHKGcnFeVIea0/CNFViUCk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=f1sVFBfc0P4R779c5VQ1VtL0BojnbpMZLeHp+EMcbfSo/5axvWqP9OchECsJevnWf dC2+VxCffos5IEZydk6/Y1WWSV4ej8uksP8dK1ZCqMnApDUS98ooeFu6KRh5klJXiL SuKhEC6BCMRtbrfqNxeSl97TmkPaQhPtBCBHOA4QFJLsyORdx4wi3ouV2iKh6y4TPi v+BCQuXZrA5DGjsFAl2jf+qdoA0cY/j5Ii+S7+zF6xY+DZUXhvxUwbVzhdmxCula/r lfis4EGaQ7ud0acwtauCW9iQL2ZV8SD/eJvn9oVQ5biWmzL/F24r8OPio9f9lc+nxt zdONEVv9XcfjQ== Date: Thu, 30 Nov 2023 12:55:29 +0530 From: Manivannan Sadhasivam To: Can Guo Cc: bvanassche@acm.org, adrian.hunter@intel.com, cmd4@qualcomm.com, beanhuo@micron.com, avri.altman@wdc.com, junwoo80.lee@samsung.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, "Bao D. Nguyen" , Andy Gross , Bjorn Andersson , Konrad Dybcio , "James E.J. Bottomley" , open list Subject: Re: [PATCH v6 10/10] scsi: ufs: ufs-qcom: Add support for UFS device version detection Message-ID: <20231130072529.GI3043@thinkpad> References: <1701246516-11626-1-git-send-email-quic_cang@quicinc.com> <1701246516-11626-11-git-send-email-quic_cang@quicinc.com> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1701246516-11626-11-git-send-email-quic_cang@quicinc.com> On Wed, Nov 29, 2023 at 12:28:35AM -0800, Can Guo wrote: > From: "Bao D. Nguyen" > > A spare register in UFS host controller is used to indicate the UFS device > version. The spare register is populated by bootloader for now, but in > future it will be populated by HW automatically during link startup with > its best efforts in any boot stages prior to Linux. > > During host driver init, read the spare register, if it is not populated > with a UFS device version, go ahead with the dual init mechanism. If a UFS > device version is in there, use the UFS device version together with host > controller's HW version to decide the proper PHY gear which should be used > to configure the UFS PHY without going through the second init. > > Signed-off-by: Bao D. Nguyen > Signed-off-by: Can Guo > --- > drivers/ufs/host/ufs-qcom.c | 23 ++++++++++++++++++----- > drivers/ufs/host/ufs-qcom.h | 2 ++ > 2 files changed, 20 insertions(+), 5 deletions(-) > > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c > index 9c0ebbc..e94dea2 100644 > --- a/drivers/ufs/host/ufs-qcom.c > +++ b/drivers/ufs/host/ufs-qcom.c > @@ -1068,15 +1068,28 @@ static void ufs_qcom_advertise_quirks(struct ufs_hba *hba) > static void ufs_qcom_set_phy_gear(struct ufs_qcom_host *host) > { > struct ufs_host_params *host_params = &host->host_params; > + u32 val, dev_major = 0; No need to initialize dev_major. > > host->phy_gear = host_params->hs_tx_gear; > > - /* > - * Power up the PHY using the minimum supported gear (UFS_HS_G2). > - * Switching to max gear will be performed during reinit if supported. > - */ > - if (host->hw_ver.major < 0x4) > + if (host->hw_ver.major < 0x4) { > + /* > + * Power up the PHY using the minimum supported gear (UFS_HS_G2). > + * Switching to max gear will be performed during reinit if supported. > + */ > host->phy_gear = UFS_HS_G2; > + } else { Can you please add a comment here to describe what is happening? > + val = ufshcd_readl(host->hba, REG_UFS_DEBUG_SPARE_CFG); > + dev_major = FIELD_GET(GENMASK(7, 4), val); It'd be good to add a macro for GENMASK(). > + > + /* UFS device version populated, no need to do init twice */ "Since the UFS device version is populated, let's remove the REINIT quirk as the negotiated gear won't change during boot. So there is no need to do reinit." > + if (dev_major != 0) 0x0 > + host->hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; > + > + /* For UFS 3.1 and older, apply HS-G4 PHY gear to save power */ > + if (dev_major < 0x4 && dev_major > 0) if (dev_major > 0x0 && dev_major < 0x4) - Mani > + host->phy_gear = UFS_HS_G4; > + } > } > > static void ufs_qcom_set_host_params(struct ufs_hba *hba) > diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h > index 11419eb..d12fc5a 100644 > --- a/drivers/ufs/host/ufs-qcom.h > +++ b/drivers/ufs/host/ufs-qcom.h > @@ -54,6 +54,8 @@ enum { > UFS_AH8_CFG = 0xFC, > > REG_UFS_CFG3 = 0x271C, > + > + REG_UFS_DEBUG_SPARE_CFG = 0x284C, > }; > > /* QCOM UFS host controller vendor specific debug registers */ > -- > 2.7.4 > > -- மணிவண்ணன் சதாசிவம்