From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752614AbeC2M0s (ORCPT ); Thu, 29 Mar 2018 08:26:48 -0400 Received: from mga14.intel.com ([192.55.52.115]:29504 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbeC2M0r (ORCPT ); Thu, 29 Mar 2018 08:26:47 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,376,1517904000"; d="scan'208";a="37859587" Subject: Re: [PATCH V4 1/3] mmc: sdhci: Add support for O2 eMMC HS200 mode To: "ernest.zhang" , Ulf Hansson , linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: xiaoguang.yu@bayhubtech.com, shirley.her@bayhubtech.com, yuxiang.wan@bayhubtech.com References: <1520604265-4430-1-git-send-email-ernest.zhang@bayhubtech.com> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: Date: Thu, 29 Mar 2018 15:25:50 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <1520604265-4430-1-git-send-email-ernest.zhang@bayhubtech.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/03/18 16:04, ernest.zhang wrote: > When use eMMC as boot device, the eMMC signaling voltage is tied to 1.8v > fixed output voltage, bios can set o2 sd host controller PCI configuration > register 0x308 bit4 to 1 to let driver skip 3.3v signaling voltage and > direct use 1.8v singling voltage in eMMC initialize process. > > Changes: Check PCIe register 0x308 bit 4 and skip eMMC 3.3v initialization > process if it is set to 1. > > Signed-off-by: ernest.zhang Notwithstanding minor formatting comment below: Acked-by: Adrian Hunter > --- > drivers/mmc/host/sdhci-pci-o2micro.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c > index 555970a..d465751 100644 > --- a/drivers/mmc/host/sdhci-pci-o2micro.c > +++ b/drivers/mmc/host/sdhci-pci-o2micro.c > @@ -3,6 +3,7 @@ > * > * Authors: Peter Guo > * Adam Lee > + * Ernest Zhang > * > * This software is licensed under the terms of the GNU General Public > * License version 2, as published by the Free Software Foundation, and > @@ -39,6 +40,7 @@ > #define O2_SD_MISC_CTRL4 0xFC > #define O2_SD_TUNING_CTRL 0x300 > #define O2_SD_PLL_SETTING 0x304 > +#define O2_SD_MISC_SETTING 0x308 > #define O2_SD_CLK_SETTING 0x328 > #define O2_SD_CAP_REG2 0x330 > #define O2_SD_CAP_REG0 0x334 > @@ -184,6 +186,7 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot) > struct sdhci_pci_chip *chip; > struct sdhci_host *host; > u32 reg; > + int ret; > > chip = slot->chip; > host = slot->host; > @@ -197,6 +200,21 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot) > if (reg & 0x1) > host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12; > > + if (chip->pdev->device == PCI_DEVICE_ID_O2_SEABIRD0) { > + ret = pci_read_config_dword(chip->pdev, > + O2_SD_MISC_SETTING, ®); > + if (ret) > + return -EIO; > + if (reg & (1 << 4)) { > + pr_info("%s: emmc 1.8v flag is set, force 1.8v signaling voltage\n", > + mmc_hostname(host->mmc)); Indenting is a little odd i.e. checkpatch says CHECK: Alignment should match open parenthesis #58: FILE: drivers/mmc/host/sdhci-pci-o2micro.c:210: + pr_info("%s: emmc 1.8v flag is set, force 1.8v signaling voltage\n", + mmc_hostname(host->mmc)) > + host->flags &= ~SDHCI_SIGNALING_330; > + host->flags |= SDHCI_SIGNALING_180; > + host->mmc->caps2 |= MMC_CAP2_NO_SD; > + host->mmc->caps2 |= MMC_CAP2_NO_SDIO; > + } > + } > + > if (chip->pdev->device != PCI_DEVICE_ID_O2_FUJIN2) > break; > /* set dll watch dog timer */ >