--- /dev/null
+/*
+ * Copyright (C) 2016 Socionext Inc.
+ * Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <linux/io.h>
+#include <linux/sizes.h>
+#include <dm/device.h>
+#include <mmc.h>
+#include <sdhci.h>
+
+/* HRS - Host Register Set (specific to Cadence) */
+#define SDHCI_CDNS_HRS04 0x10 /* PHY access port */
+#define SDHCI_CDNS_HRS04_ACK BIT(26)
+#define SDHCI_CDNS_HRS04_RD BIT(25)
+#define SDHCI_CDNS_HRS04_WR BIT(24)
+#define SDHCI_CDNS_HRS04_RDATA_SHIFT 12
+#define SDHCI_CDNS_HRS04_WDATA_SHIFT 8
+#define SDHCI_CDNS_HRS04_ADDR_SHIFT 0
+
+/* SRS - Slot Register Set (SDHCI-compatible) */
+#define SDHCI_CDNS_SRS_BASE 0x200
+
+/* PHY */
+#define SDHCI_CDNS_PHY_DLY_SD_HS 0x00
+#define SDHCI_CDNS_PHY_DLY_SD_DEFAULT 0x01
+#define SDHCI_CDNS_PHY_DLY_UHS_SDR12 0x02
+#define SDHCI_CDNS_PHY_DLY_UHS_SDR25 0x03
+#define SDHCI_CDNS_PHY_DLY_UHS_SDR50 0x04
+#define SDHCI_CDNS_PHY_DLY_UHS_DDR50 0x05
+#define SDHCI_CDNS_PHY_DLY_EMMC_LEGACY 0x06
+#define SDHCI_CDNS_PHY_DLY_EMMC_SDR 0x07
+#define SDHCI_CDNS_PHY_DLY_EMMC_DDR 0x08
+
+struct sdhci_cdns_plat {
+ struct mmc_config cfg;
+ struct mmc mmc;
+ void __iomem *hrs_addr;
+};
+
+static void sdhci_cdns_write_phy_reg(struct sdhci_cdns_plat *plat,
+ u8 addr, u8 data)
+{
+ void __iomem *reg = plat->hrs_addr + SDHCI_CDNS_HRS04;
+ u32 tmp;
+
+ tmp = (data << SDHCI_CDNS_HRS04_WDATA_SHIFT) |
+ (addr << SDHCI_CDNS_HRS04_ADDR_SHIFT);
+ writel(tmp, reg);
+
+ tmp |= SDHCI_CDNS_HRS04_WR;
+ writel(tmp, reg);
+
+ tmp &= ~SDHCI_CDNS_HRS04_WR;
+ writel(tmp, reg);
+}
+
+static void sdhci_cdns_phy_init(struct sdhci_cdns_plat *plat)
+{
+ sdhci_cdns_write_phy_reg(plat, SDHCI_CDNS_PHY_DLY_SD_HS, 4);
+ sdhci_cdns_write_phy_reg(plat, SDHCI_CDNS_PHY_DLY_SD_DEFAULT, 4);
+ sdhci_cdns_write_phy_reg(plat, SDHCI_CDNS_PHY_DLY_EMMC_LEGACY, 9);
+ sdhci_cdns_write_phy_reg(plat, SDHCI_CDNS_PHY_DLY_EMMC_SDR, 2);
+ sdhci_cdns_write_phy_reg(plat, SDHCI_CDNS_PHY_DLY_EMMC_DDR, 3);
+}
+
+static int sdhci_cdns_bind(struct udevice *dev)
+{
+ struct sdhci_cdns_plat *plat = dev_get_platdata(dev);
+
+ return sdhci_bind(dev, &plat->mmc, &plat->cfg);
+}
+
+static int sdhci_cdns_probe(struct udevice *dev)
+{
+ struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
+ struct sdhci_cdns_plat *plat = dev_get_platdata(dev);
+ struct sdhci_host *host = dev_get_priv(dev);
+ fdt_addr_t base;
+ int ret;
+
+ base = dev_get_addr(dev);
+ if (base == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ plat->hrs_addr = devm_ioremap(dev, base, SZ_1K);
+ if (!plat->hrs_addr)
+ return -ENOMEM;
+
+ host->name = dev->name;
+ host->ioaddr = plat->hrs_addr + SDHCI_CDNS_SRS_BASE;
+ host->quirks |= SDHCI_QUIRK_WAIT_SEND_CMD;
+
+ sdhci_cdns_phy_init(plat);
+
+ ret = sdhci_setup_cfg(&plat->cfg, host, 0, 0);
+ if (ret)
+ return ret;
+
+ upriv->mmc = &plat->mmc;
+ host->mmc = &plat->mmc;
+ host->mmc->priv = host;
+
+ return sdhci_probe(dev);
+}
+
+static const struct udevice_id sdhci_cdns_match[] = {
+ { .compatible = "socionext,uniphier-sd4hc" },
+ { .compatible = "cdns,sd4hc" },
+ { /* sentinel */ }
+};
+
+U_BOOT_DRIVER(sdhci_cdns) = {
+ .name = "sdhci-cdns",
+ .id = UCLASS_MMC,
+ .of_match = sdhci_cdns_match,
+ .bind = sdhci_cdns_bind,
+ .probe = sdhci_cdns_probe,
+ .priv_auto_alloc_size = sizeof(struct sdhci_host),
+ .platdata_auto_alloc_size = sizeof(struct sdhci_cdns_plat),
+ .ops = &sdhci_ops,
+};