--- /dev/null
+Synopsys Designware Mobile Storage Host Controller extensions
+used in Synopsys ARC devboards
+
+Required Properties:
+
+* compatible: should be - "snps,dw-mshc".
+* bus-width: number of data lines connected to the controller.
+* clocks: from common clock binding: handle to biu and ciu clocks for the
+ bus interface unit clock and the card interface unit clock.
+* clock-names: from common clock binding: Shall be "biu" and "ciu".
+
+Optional properties:
+
+* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
+ specified, the default value of the fifo size is determined from the
+ controller registers.
+* fifo-mode: Don't use DMA.
+* max-frequency: Maximum operating clock frequency, driver uses 'ciu' clock
+ frequency if it is not set.
+
+Example:
+
+mmc0@f000a000 {
+ compatible = "snps,dw-mshc";
+ reg = <0xf000a000 0x400>;
+
+ bus-width = <4>;
+ fifo-depth = <256>;
+ clocks = <&mmcclk_biu>, <&mmcclk_ciu>;
+ clock-names = "biu", "ciu";
+ max-frequency = <25000000>;
+};
+
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Synopsys DesignWare Multimedia Card Interface driver
+ * extensions used in various Synopsys ARC devboards.
+ *
+ * Copyright (C) 2019 Synopsys
+ * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <dwmmc.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <linux/libfdt.h>
+#include <linux/err.h>
+#include <malloc.h>
+
+#define CLOCK_MIN 400000 /* 400 kHz */
+#define FIFO_MIN 8
+#define FIFO_MAX 4096
+
+struct snps_dwmci_plat {
+ struct mmc_config cfg;
+ struct mmc mmc;
+};
+
+struct snps_dwmci_priv_data {
+ struct dwmci_host host;
+ u32 f_max;
+};
+
+static int snps_dwmmc_clk_setup(struct udevice *dev)
+{
+ struct snps_dwmci_priv_data *priv = dev_get_priv(dev);
+ struct dwmci_host *host = &priv->host;
+
+ struct clk clk_ciu, clk_biu;
+ int ret;
+
+ ret = clk_get_by_name(dev, "ciu", &clk_ciu);
+ if (ret)
+ goto clk_err;
+
+ ret = clk_enable(&clk_ciu);
+ if (ret && ret != -ENOSYS && ret != -ENOTSUPP)
+ goto clk_err_ciu;
+
+ host->bus_hz = clk_get_rate(&clk_ciu);
+ if (host->bus_hz < CLOCK_MIN) {
+ ret = -EINVAL;
+ goto clk_err_ciu_dis;
+ }
+
+ ret = clk_get_by_name(dev, "biu", &clk_biu);
+ if (ret)
+ goto clk_err_ciu_dis;
+
+ ret = clk_enable(&clk_biu);
+ if (ret && ret != -ENOSYS && ret != -ENOTSUPP)
+ goto clk_err_biu;
+
+ return 0;
+
+clk_err_biu:
+ clk_free(&clk_biu);
+clk_err_ciu_dis:
+ clk_disable(&clk_ciu);
+clk_err_ciu:
+ clk_free(&clk_ciu);
+clk_err:
+ dev_err(dev, "failed to setup clocks, ret %d\n", ret);
+
+ return ret;
+}
+
+static int snps_dwmmc_ofdata_to_platdata(struct udevice *dev)
+{
+ struct snps_dwmci_priv_data *priv = dev_get_priv(dev);
+ struct dwmci_host *host = &priv->host;
+ u32 fifo_depth;
+ int ret;
+
+ host->ioaddr = devfdt_get_addr_ptr(dev);
+
+ /*
+ * If fifo-depth is unset don't set fifoth_val - we will try to
+ * auto detect it.
+ */
+ ret = dev_read_u32(dev, "fifo-depth", &fifo_depth);
+ if (!ret) {
+ if (fifo_depth < FIFO_MIN || fifo_depth > FIFO_MAX)
+ return -EINVAL;
+
+ host->fifoth_val = MSIZE(0x2) |
+ RX_WMARK(fifo_depth / 2 - 1) |
+ TX_WMARK(fifo_depth / 2);
+ }
+
+ host->buswidth = dev_read_u32_default(dev, "bus-width", 4);
+ if (host->buswidth != 1 && host->buswidth != 4 && host->buswidth != 8)
+ return -EINVAL;
+
+ /*
+ * If max-frequency is unset don't set priv->f_max - we will use
+ * host->bus_hz in probe() instead.
+ */
+ ret = dev_read_u32(dev, "max-frequency", &priv->f_max);
+ if (!ret && priv->f_max < CLOCK_MIN)
+ return -EINVAL;
+
+ host->fifo_mode = dev_read_bool(dev, "fifo-mode");
+ host->name = dev->name;
+ host->dev_index = 0;
+ host->priv = priv;
+
+ return 0;
+}
+
+int snps_dwmmc_getcd(struct udevice *dev)
+{
+ struct snps_dwmci_priv_data *priv = dev_get_priv(dev);
+ struct dwmci_host *host = &priv->host;
+
+ return !(dwmci_readl(host, DWMCI_CDETECT) & 1);
+}
+
+struct dm_mmc_ops snps_dwmci_dm_ops;
+
+static int snps_dwmmc_probe(struct udevice *dev)
+{
+#ifdef CONFIG_BLK
+ struct snps_dwmci_plat *plat = dev_get_platdata(dev);
+#endif
+ struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
+ struct snps_dwmci_priv_data *priv = dev_get_priv(dev);
+ struct dwmci_host *host = &priv->host;
+ unsigned int clock_max;
+ int ret;
+
+ /* Extend generic 'dm_dwmci_ops' with our 'getcd' implementation */
+ memcpy(&snps_dwmci_dm_ops, &dm_dwmci_ops, sizeof(struct dm_mmc_ops));
+ snps_dwmci_dm_ops.get_cd = snps_dwmmc_getcd;
+
+ ret = snps_dwmmc_clk_setup(dev);
+ if (ret)
+ return ret;
+
+ if (!priv->f_max)
+ clock_max = host->bus_hz;
+ else
+ clock_max = min_t(unsigned int, host->bus_hz, priv->f_max);
+
+#ifdef CONFIG_BLK
+ dwmci_setup_cfg(&plat->cfg, host, clock_max, CLOCK_MIN);
+ host->mmc = &plat->mmc;
+#else
+ ret = add_dwmci(host, clock_max, CLOCK_MIN);
+ if (ret)
+ return ret;
+#endif
+ host->mmc->priv = &priv->host;
+ upriv->mmc = host->mmc;
+ host->mmc->dev = dev;
+
+ return dwmci_probe(dev);
+}
+
+static int snps_dwmmc_bind(struct udevice *dev)
+{
+#ifdef CONFIG_BLK
+ struct snps_dwmci_plat *plat = dev_get_platdata(dev);
+ int ret;
+
+ ret = dwmci_bind(dev, &plat->mmc, &plat->cfg);
+ if (ret)
+ return ret;
+#endif
+
+ return 0;
+}
+
+static const struct udevice_id snps_dwmmc_ids[] = {
+ { .compatible = "snps,dw-mshc" },
+ { }
+};
+
+U_BOOT_DRIVER(snps_dwmmc_drv) = {
+ .name = "snps_dw_mmc",
+ .id = UCLASS_MMC,
+ .of_match = snps_dwmmc_ids,
+ .ofdata_to_platdata = snps_dwmmc_ofdata_to_platdata,
+ .ops = &snps_dwmci_dm_ops,
+ .bind = snps_dwmmc_bind,
+ .probe = snps_dwmmc_probe,
+ .priv_auto_alloc_size = sizeof(struct snps_dwmci_priv_data),
+ .platdata_auto_alloc_size = sizeof(struct snps_dwmci_plat),
+};