From 8d2e334377dbe645415fbe031711324bc2281907 Mon Sep 17 00:00:00 2001 From: Manish Narani Date: Tue, 21 Jan 2020 15:51:34 +0530 Subject: [PATCH] mmc: sdhci-of-arasan: Add support for DLL reset for ZynqMP platforms The DLL resets are required while executing the auto tuning procedure in ZynqMP. This patch adds code to support the same. Signed-off-by: Manish Narani Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/1579602095-30060-4-git-send-email-manish.narani@xilinx.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-of-arasan.c | 46 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c index e49b44b..39176ab 100644 --- a/drivers/mmc/host/sdhci-of-arasan.c +++ b/drivers/mmc/host/sdhci-of-arasan.c @@ -757,6 +757,50 @@ static const struct clk_ops zynqmp_sampleclk_ops = { .set_phase = sdhci_zynqmp_sampleclk_set_phase, }; +static void arasan_zynqmp_dll_reset(struct sdhci_host *host, u32 deviceid) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host); + struct sdhci_arasan_zynqmp_clk_data *zynqmp_clk_data = + sdhci_arasan->clk_data.clk_of_data; + const struct zynqmp_eemi_ops *eemi_ops = zynqmp_clk_data->eemi_ops; + u16 clk; + + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL); + clk &= ~(SDHCI_CLOCK_CARD_EN | SDHCI_CLOCK_INT_EN); + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL); + + /* Issue DLL Reset */ + eemi_ops->ioctl(deviceid, IOCTL_SD_DLL_RESET, + PM_DLL_RESET_PULSE, 0, NULL); + + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL); + + sdhci_enable_clk(host, clk); +} + +static int arasan_zynqmp_execute_tuning(struct mmc_host *mmc, u32 opcode) +{ + struct sdhci_host *host = mmc_priv(mmc); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host); + struct clk_hw *hw = &sdhci_arasan->clk_data.sdcardclk_hw; + const char *clk_name = clk_hw_get_name(hw); + u32 device_id = !strcmp(clk_name, "clk_out_sd0") ? NODE_SD_0 : + NODE_SD_1; + int err; + + arasan_zynqmp_dll_reset(host, device_id); + + err = sdhci_execute_tuning(mmc, opcode); + if (err) + return err; + + arasan_zynqmp_dll_reset(host, device_id); + + return 0; +} + /** * sdhci_arasan_update_clockmultiplier - Set corecfg_clockmultiplier * @@ -1247,6 +1291,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev) zynqmp_clk_data->eemi_ops = eemi_ops; sdhci_arasan->clk_data.clk_of_data = zynqmp_clk_data; + host->mmc_host_ops.execute_tuning = + arasan_zynqmp_execute_tuning; } arasan_dt_parse_clk_phases(&pdev->dev, &sdhci_arasan->clk_data); -- 2.7.4