From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH 20/23] mmc: sdhci-esdhc-imx: fix strobe DLL lock wrong clock issue Date: Tue, 10 May 2016 15:03:48 +0300 Message-ID: <5731CE24.2090002@intel.com> References: <1460741387-23815-1-git-send-email-aisheng.dong@nxp.com> <1460741387-23815-21-git-send-email-aisheng.dong@nxp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mga14.intel.com ([192.55.52.115]:11025 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751628AbcEJMHr (ORCPT ); Tue, 10 May 2016 08:07:47 -0400 In-Reply-To: <1460741387-23815-21-git-send-email-aisheng.dong@nxp.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Dong Aisheng , linux-mmc@vger.kernel.org Cc: ulf.hansson@linaro.org, chris@printf.net, shawnguo@kernel.org, linux-arm-kernel@lists.infradead.org, haibo.chen@nxp.com, dongas86@gmail.com On 15/04/16 20:29, Dong Aisheng wrote: > When enable DDR, the clock factor definition is changed. > e.g. original 200Mhz will become 100Mhz one MIX_CTRL_DDREN bit is set > So we need to update the clock setting then the strobe dll can lock > the correct clock rate. > > Additionally we also need disable the clock before locking strobe dll. > > Signed-off-by: Dong Aisheng Apart from redundant parentheses (refer below): Acked-by: Adrian Hunter > --- > drivers/mmc/host/sdhci-esdhc-imx.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c > index 07b1144..3ff213f 100644 > --- a/drivers/mmc/host/sdhci-esdhc-imx.c > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c > @@ -852,6 +852,11 @@ static void esdhc_set_strobe_dll(struct sdhci_host *host) > u32 v; > > if (host->mmc->actual_clock > ESDHC_STROBE_DLL_CLK_FREQ) { > + /* disable clock before enabling strobe dll */ > + writel(readl(host->ioaddr + ESDHC_VENDOR_SPEC) & > + (~ESDHC_VENDOR_SPEC_FRC_SDCLK_ON), Parentheses look redundant > + host->ioaddr + ESDHC_VENDOR_SPEC); > + > /* force a reset on strobe dll */ > writel(ESDHC_STROBE_DLL_CTRL_RESET, > host->ioaddr + ESDHC_STROBE_DLL_CTRL); > @@ -913,6 +918,8 @@ static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing) > m |= ESDHC_MIX_CTRL_DDREN | ESDHC_MIX_CTRL_HS400_EN; > writel(m, host->ioaddr + ESDHC_MIX_CTRL); > imx_data->is_ddr = 1; > + /* update clock after enable DDR for strobe DLL lock */ > + host->ops->set_clock(host, host->clock); > esdhc_set_strobe_dll(host); > break; > } >