From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ritesh Harjani Subject: [PATCH v3 8/9] mmc: sdhci-msm: Add clock changes for DDR mode. Date: Fri, 19 Aug 2016 10:06:23 +0530 Message-ID: <1471581384-18961-9-git-send-email-riteshh@codeaurora.org> References: <1471581384-18961-1-git-send-email-riteshh@codeaurora.org> Return-path: In-Reply-To: <1471581384-18961-1-git-send-email-riteshh@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org To: adrian.hunter@intel.com Cc: ulf.hansson@linaro.org, bjorn.andersson@linaro.org, shawn.lin@rock-chips.com, jh80.chung@samsung.com, linux-mmc@vger.kernel.org, linux-arm-msm@vger.kernel.org, georgi.djakov@linaro.org, alex.lemberg@sandisk.com, mateusz.nowak@intel.com, Yuliy.Izrailov@sandisk.com, asutoshd@codeaurora.org, kdorfman@codeaurora.org, david.griego@linaro.org, stummala@codeaurora.org, venkatg@codeaurora.org, Ritesh Harjani List-Id: linux-mmc@vger.kernel.org SDHC MSM controller need 2x clock for MCLK at GCC. Hence make required changes to have 2x clock for DDR timing modes. Signed-off-by: Ritesh Harjani --- drivers/mmc/host/sdhci-msm.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index c0ad9c2..f0e6293 100644 --- a/drivers/mmc/host/sdhci-msm.c +++ b/drivers/mmc/host/sdhci-msm.c @@ -661,21 +661,35 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock) { struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host); - u32 msm_clock = 0; + struct mmc_ios curr_ios = host->mmc->ios; + u32 msm_clock = clock, ddr_clock = 0; int rc = 0; if (!clock) goto out; - if (clock != msm_host->clk_rate) { - msm_clock = sdhci_msm_get_msm_clk_rate(host, clock); + msm_clock = sdhci_msm_get_msm_clk_rate(host, clock); + if ((curr_ios.timing == MMC_TIMING_UHS_DDR50) || + (curr_ios.timing == MMC_TIMING_MMC_DDR52) || + (curr_ios.timing == MMC_TIMING_MMC_HS400)) { + /* + * The SDHC requires internal clock frequency to be double the + * actual clock that will be set for DDR mode. The controller + * uses the faster clock(100/400MHz) for some of its parts and + * send the actual required clock (50/200MHz) to the card. + */ + ddr_clock = clock * 2; + msm_clock = sdhci_msm_get_msm_clk_rate(host, ddr_clock); + } + + if (msm_clock != msm_host->clk_rate) { rc = clk_set_rate(msm_host->clk, msm_clock); if (rc) { pr_err("%s: failed to set clock at rate %u, requested clock rate %u\n", mmc_hostname(host->mmc), msm_clock, clock); goto out; } - msm_host->clk_rate = clock; + msm_host->clk_rate = msm_clock; pr_debug("%s: setting clock at rate %lu\n", mmc_hostname(host->mmc), clk_get_rate(msm_host->clk)); } -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.