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 1D1B91E51F; Thu, 30 Nov 2023 07:29:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eWirZx2e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E364BC433C8; Thu, 30 Nov 2023 07:29:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701329350; bh=dyoP5GxI47SkSPARVksRZSB18YswC7fIj5rxMeiVlMM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=eWirZx2eiNBm1xpvsYjjKUsfOMId8hoQ1XftDSWXUUO3Mx/CQ1tEbl6zQwPAIBLze 8nxWYGYPVaLY+BwAcWhv0l61i8ovPYnQ8ljdcFCXO01+LpW3kpzjyDcqRxHeImWSgY VuRMu5V2Wl2EwlAEgYkba/6o2fdmjlgVRXAyrtN3Bxy5x5gKkui/IUlQ2xS7tXEe9a dB/+Jts/YllTpPSleLeYxMrDDkmMlOHQFVJDjx5QatkUQhKUA5bTNKttchzeoLbujX WInYQImZF/jOXf7Cvfh7JB3IngUvodKng/B83iWelgnR7ldTXT/njPHk4oKlNWTJpO Vnck+CazlAqMw== Date: Thu, 30 Nov 2023 12:58:59 +0530 From: Manivannan Sadhasivam To: Eric Chanudet Cc: Can Guo , 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: <20231130072859.GJ3043@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: On Wed, Nov 29, 2023 at 02:04:35PM -0500, Eric Chanudet wrote: > 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; > > > > 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 { > > + val = ufshcd_readl(host->hba, REG_UFS_DEBUG_SPARE_CFG); > > + dev_major = FIELD_GET(GENMASK(7, 4), val); > > + > > + /* UFS device version populated, no need to do init twice */ > > This change documents the content of the register as "UFS device > version", both inline in the code and in the commit description. Earlier > in this series[1], Mani mentioned it was the gear info: > > > [...]populating a spare register in the bootloader with the max gear > > > info that the bootloader has already found[...] > > Is it the gear number as in HS-G4? Or the version as in UFS controller > revision 3.1? > That was a mistake from my end, apologies. The register has the device version only and the driver uses both device and host controller's version info to decide the initial gear. - Mani > [1] https://lore.kernel.org/all/20231018124741.GA47321@thinkpad/ > > > + if (dev_major != 0) > > + 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) > > + 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 > > > > > > -- > Eric Chanudet > > -- மணிவண்ணன் சதாசிவம்