--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2009 SAMSUNG Electronics
+ * Minkyu Kang <mk7.kang@samsung.com>
+ * Jaehoon Chung <jh80.chung@samsung.com>
+ * Portions Copyright 2011-2019 NVIDIA Corporation
+ * Portions Copyright 2021 Tianrui Wei
+ * This file is adapted from tegra_mmc.c
+ * Tianrui Wei <tianrui-wei@outlook.com>
+ */
+
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <common.h>
+#include <div64.h>
+#include <dm.h>
+#include <errno.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/sizes.h>
+#include <log.h>
+#include <mmc.h>
+
+
+#define PITON_MMC_DUMMY_F_MAX 20000000
+#define PITON_MMC_DUMMY_F_MIN 10000000
+#define PITON_MMC_DUMMY_CAPACITY SZ_4G << 3
+#define PITON_MMC_DUMMY_B_MAX SZ_4G
+
+struct piton_mmc_plat {
+ struct mmc_config cfg;
+ struct mmc mmc;
+};
+
+struct piton_mmc_priv {
+ void __iomem *base_addr;
+};
+
+static int piton_mmc_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
+ struct mmc_data *data)
+{
+ if (!data)
+ return 0;
+
+ struct piton_mmc_priv *priv = dev_get_priv(dev);
+ u32 *buff, *start_addr, *write_src;
+ size_t byte_cnt, start_block;
+
+ buff = (u32 *)data->dest;
+ write_src = (u32 *)data->src;
+ start_block = cmd->cmdarg;
+ start_addr = priv->base_addr + start_block;
+
+ /* if there is a read */
+ for (byte_cnt = data->blocks * data->blocksize; byte_cnt;
+ byte_cnt -= sizeof(u32)) {
+ if (data->flags & MMC_DATA_READ) {
+ *buff++ = readl(start_addr++);
+ }
+ else if (data->flags & MMC_DATA_WRITE) {
+ writel(*write_src++,start_addr++);
+ }
+ }
+ return 0;
+}
+
+static int piton_mmc_ofdata_to_platdata(struct udevice *dev)
+{
+ struct piton_mmc_priv *priv = dev_get_priv(dev);
+ struct piton_mmc_plat *plat = dev_get_plat(dev);
+ struct mmc_config *cfg;
+ struct mmc *mmc;
+ struct blk_desc *bdesc;
+
+ priv->base_addr = (void *)dev_read_addr(dev);
+ cfg = &plat->cfg;
+ cfg->name = "PITON MMC";
+ cfg->host_caps = MMC_MODE_8BIT;
+ cfg->f_max = PITON_MMC_DUMMY_F_MAX;
+ cfg->f_min = PITON_MMC_DUMMY_F_MIN;
+ cfg->voltages = MMC_VDD_21_22;
+
+ mmc = &plat->mmc;
+ mmc->read_bl_len = MMC_MAX_BLOCK_LEN;
+ mmc->capacity_user = PITON_MMC_DUMMY_CAPACITY;
+ mmc->capacity_user *= mmc->read_bl_len;
+ mmc->capacity_boot = 0;
+ mmc->capacity_rpmb = 0;
+ for (int i = 0; i < 4; i++)
+ mmc->capacity_gp[i] = 0;
+ mmc->capacity = PITON_MMC_DUMMY_CAPACITY;
+ mmc->has_init = 1;
+
+ bdesc = mmc_get_blk_desc(mmc);
+ bdesc->lun = 0;
+ bdesc->hwpart = 0;
+ bdesc->type = 0;
+ bdesc->blksz = mmc->read_bl_len;
+ bdesc->log2blksz = LOG2(bdesc->blksz);
+ bdesc->lba = lldiv(mmc->capacity, mmc->read_bl_len);
+
+ return 0;
+}
+
+static int piton_mmc_getcd(struct udevice *dev)
+{
+ return 1;
+}
+
+static const struct dm_mmc_ops piton_mmc_ops = {
+ .send_cmd = piton_mmc_send_cmd,
+ .get_cd = piton_mmc_getcd,
+};
+
+static int piton_mmc_probe(struct udevice *dev)
+{
+ struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
+ struct piton_mmc_plat *plat = dev_get_plat(dev);
+ struct mmc_config *cfg = &plat->cfg;
+
+ cfg->name = dev->name;
+ upriv->mmc = &plat->mmc;
+ upriv->mmc->has_init = 1;
+ upriv->mmc->capacity = PITON_MMC_DUMMY_CAPACITY;
+ upriv->mmc->read_bl_len = MMC_MAX_BLOCK_LEN;
+ return 0;
+}
+
+static int piton_mmc_bind(struct udevice *dev)
+{
+ struct piton_mmc_plat *plat = dev_get_plat(dev);
+ struct mmc_config *cfg = &plat->cfg;
+
+ cfg->name = dev->name;
+ cfg->host_caps = MMC_MODE_HS_52MHz | MMC_MODE_HS | MMC_MODE_8BIT;
+ cfg->voltages = MMC_VDD_165_195 | MMC_VDD_32_33 | MMC_VDD_33_34;
+ cfg->f_min = PITON_MMC_DUMMY_F_MIN;
+ cfg->f_max = PITON_MMC_DUMMY_F_MAX;
+ cfg->b_max = MMC_MAX_BLOCK_LEN;
+
+ return mmc_bind(dev, &plat->mmc, cfg);
+}
+
+static const struct udevice_id piton_mmc_ids[] = {
+ {.compatible = "openpiton,piton-mmc"},
+ {/* sentinel */}
+};
+
+U_BOOT_DRIVER(piton_mmc_drv) = {
+ .name = "piton_mmc",
+ .id = UCLASS_MMC,
+ .of_match = piton_mmc_ids,
+ .of_to_plat = piton_mmc_ofdata_to_platdata,
+ .bind = piton_mmc_bind,
+ .probe = piton_mmc_probe,
+ .ops = &piton_mmc_ops,
+ .plat_auto = sizeof(struct piton_mmc_plat),
+ .priv_auto = sizeof(struct piton_mmc_priv),
+};