mmc: s3c: Add SD driver

Implement SD driver for the S3C24xx family. This implementation
is currently only capable of using the PIO transfers, DMA is not
supported.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
diff --git a/drivers/mmc/s3c_sdi.c b/drivers/mmc/s3c_sdi.c
new file mode 100644
index 0000000..1b5b705
--- /dev/null
+++ b/drivers/mmc/s3c_sdi.c
@@ -0,0 +1,321 @@
+/*
+ * S3C24xx SD/MMC driver
+ *
+ * Based on OpenMoko S3C24xx driver by Harald Welte <laforge@openmoko.org>
+ *
+ * Copyright (C) 2014 Marek Vasut <marex@denx.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <mmc.h>
+#include <errno.h>
+#include <asm/arch/s3c24x0_cpu.h>
+#include <asm/io.h>
+#include <asm/unaligned.h>
+
+#define S3C2440_SDICON_SDRESET		(1 << 8)
+#define S3C2410_SDICON_FIFORESET	(1 << 1)
+#define S3C2410_SDICON_CLOCKTYPE	(1 << 0)
+
+#define S3C2410_SDICMDCON_LONGRSP	(1 << 10)
+#define S3C2410_SDICMDCON_WAITRSP	(1 << 9)
+#define S3C2410_SDICMDCON_CMDSTART	(1 << 8)
+#define S3C2410_SDICMDCON_SENDERHOST	(1 << 6)
+#define S3C2410_SDICMDCON_INDEX		0x3f
+
+#define S3C2410_SDICMDSTAT_CRCFAIL	(1 << 12)
+#define S3C2410_SDICMDSTAT_CMDSENT	(1 << 11)
+#define S3C2410_SDICMDSTAT_CMDTIMEOUT	(1 << 10)
+#define S3C2410_SDICMDSTAT_RSPFIN	(1 << 9)
+
+#define S3C2440_SDIDCON_DS_WORD		(2 << 22)
+#define S3C2410_SDIDCON_TXAFTERRESP	(1 << 20)
+#define S3C2410_SDIDCON_RXAFTERCMD	(1 << 19)
+#define S3C2410_SDIDCON_BLOCKMODE	(1 << 17)
+#define S3C2410_SDIDCON_WIDEBUS		(1 << 16)
+#define S3C2440_SDIDCON_DATSTART	(1 << 14)
+#define S3C2410_SDIDCON_XFER_RXSTART	(2 << 12)
+#define S3C2410_SDIDCON_XFER_TXSTART	(3 << 12)
+#define S3C2410_SDIDCON_BLKNUM		0x7ff
+
+#define S3C2410_SDIDSTA_FIFOFAIL	(1 << 8)
+#define S3C2410_SDIDSTA_CRCFAIL		(1 << 7)
+#define S3C2410_SDIDSTA_RXCRCFAIL	(1 << 6)
+#define S3C2410_SDIDSTA_DATATIMEOUT	(1 << 5)
+#define S3C2410_SDIDSTA_XFERFINISH	(1 << 4)
+
+#define S3C2410_SDIFSTA_TFHALF		(1 << 11)
+#define S3C2410_SDIFSTA_COUNTMASK	0x7f
+
+/*
+ * WARNING: We only support one SD IP block.
+ * NOTE: It's not likely there will ever exist an S3C24xx with two,
+ *       at least not in this universe all right.
+ */
+static int wide_bus;
+
+static int
+s3cmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
+{
+	struct s3c24x0_sdi *sdi_regs = s3c24x0_get_base_sdi();
+	uint32_t sdiccon, sdicsta, sdidcon, sdidsta, sdidat, sdifsta;
+	uint32_t sdicsta_wait_bit = S3C2410_SDICMDSTAT_CMDSENT;
+	unsigned int timeout = 100000;
+	int ret = 0, xfer_len, data_offset = 0;
+	const uint32_t sdidsta_err_mask = S3C2410_SDIDSTA_FIFOFAIL |
+		S3C2410_SDIDSTA_CRCFAIL | S3C2410_SDIDSTA_RXCRCFAIL |
+		S3C2410_SDIDSTA_DATATIMEOUT;
+
+
+	writel(0xffffffff, &sdi_regs->sdicsta);
+	writel(0xffffffff, &sdi_regs->sdidsta);
+	writel(0xffffffff, &sdi_regs->sdifsta);
+
+	/* Set up data transfer (if applicable). */
+	if (data) {
+		writel(data->blocksize, &sdi_regs->sdibsize);
+
+		sdidcon = data->blocks & S3C2410_SDIDCON_BLKNUM;
+		sdidcon |= S3C2410_SDIDCON_BLOCKMODE;
+#if defined(CONFIG_S3C2440)
+		sdidcon |= S3C2440_SDIDCON_DS_WORD | S3C2440_SDIDCON_DATSTART;
+#endif
+		if (wide_bus)
+			sdidcon |= S3C2410_SDIDCON_WIDEBUS;
+
+		if (data->flags & MMC_DATA_READ) {
+			sdidcon |= S3C2410_SDIDCON_RXAFTERCMD;
+			sdidcon |= S3C2410_SDIDCON_XFER_RXSTART;
+		} else {
+			sdidcon |= S3C2410_SDIDCON_TXAFTERRESP;
+			sdidcon |= S3C2410_SDIDCON_XFER_TXSTART;
+		}
+
+		writel(sdidcon, &sdi_regs->sdidcon);
+	}
+
+	/* Write CMD arg. */
+	writel(cmd->cmdarg, &sdi_regs->sdicarg);
+
+	/* Write CMD index. */
+	sdiccon = cmd->cmdidx & S3C2410_SDICMDCON_INDEX;
+	sdiccon |= S3C2410_SDICMDCON_SENDERHOST;
+	sdiccon |= S3C2410_SDICMDCON_CMDSTART;
+
+	/* Command with short response. */
+	if (cmd->resp_type & MMC_RSP_PRESENT) {
+		sdiccon |= S3C2410_SDICMDCON_WAITRSP;
+		sdicsta_wait_bit = S3C2410_SDICMDSTAT_RSPFIN;
+	}
+
+	/* Command with long response. */
+	if (cmd->resp_type & MMC_RSP_136)
+		sdiccon |= S3C2410_SDICMDCON_LONGRSP;
+
+	/* Start the command. */
+	writel(sdiccon, &sdi_regs->sdiccon);
+
+	/* Wait for the command to complete or for response. */
+	for (timeout = 100000; timeout; timeout--) {
+		sdicsta = readl(&sdi_regs->sdicsta);
+		if (sdicsta & sdicsta_wait_bit)
+			break;
+
+		if (sdicsta & S3C2410_SDICMDSTAT_CMDTIMEOUT)
+			timeout = 1;
+	}
+
+	/* Clean the status bits. */
+	setbits_le32(&sdi_regs->sdicsta, 0xf << 9);
+
+	if (!timeout) {
+		puts("S3C SDI: Command timed out!\n");
+		ret = TIMEOUT;
+		goto error;
+	}
+
+	/* Read out the response. */
+	if (cmd->resp_type & MMC_RSP_136) {
+		cmd->response[0] = readl(&sdi_regs->sdirsp0);
+		cmd->response[1] = readl(&sdi_regs->sdirsp1);
+		cmd->response[2] = readl(&sdi_regs->sdirsp2);
+		cmd->response[3] = readl(&sdi_regs->sdirsp3);
+	} else {
+		cmd->response[0] = readl(&sdi_regs->sdirsp0);
+	}
+
+	/* If there are no data, we're done. */
+	if (!data)
+		return 0;
+
+	xfer_len = data->blocksize * data->blocks;
+
+	while (xfer_len > 0) {
+		sdidsta = readl(&sdi_regs->sdidsta);
+		sdifsta = readl(&sdi_regs->sdifsta);
+
+		if (sdidsta & sdidsta_err_mask) {
+			printf("S3C SDI: Data error (sdta=0x%08x)\n", sdidsta);
+			ret = -EIO;
+			goto error;
+		}
+
+		if (data->flags & MMC_DATA_READ) {
+			if ((sdifsta & S3C2410_SDIFSTA_COUNTMASK) < 4)
+				continue;
+			sdidat = readl(&sdi_regs->sdidat);
+			put_unaligned_le32(sdidat, data->dest + data_offset);
+		} else {	/* Write */
+			/* TX FIFO half full. */
+			if (!(sdifsta & S3C2410_SDIFSTA_TFHALF))
+				continue;
+
+			/* TX FIFO is below 32b full, write. */
+			sdidat = get_unaligned_le32(data->src + data_offset);
+			writel(sdidat, &sdi_regs->sdidat);
+		}
+		data_offset += 4;
+		xfer_len -= 4;
+	}
+
+	/* Wait for the command to complete or for response. */
+	for (timeout = 100000; timeout; timeout--) {
+		sdidsta = readl(&sdi_regs->sdidsta);
+		if (sdidsta & S3C2410_SDIDSTA_XFERFINISH)
+			break;
+
+		if (sdidsta & S3C2410_SDIDSTA_DATATIMEOUT)
+			timeout = 1;
+	}
+
+	/* Clear status bits. */
+	writel(0x6f8, &sdi_regs->sdidsta);
+
+	if (!timeout) {
+		puts("S3C SDI: Command timed out!\n");
+		ret = TIMEOUT;
+		goto error;
+	}
+
+	writel(0, &sdi_regs->sdidcon);
+
+	return 0;
+error:
+	return ret;
+}
+
+static void s3cmmc_set_ios(struct mmc *mmc)
+{
+	struct s3c24x0_sdi *sdi_regs = s3c24x0_get_base_sdi();
+	uint32_t divider = 0;
+
+	wide_bus = (mmc->bus_width == 4);
+
+	if (!mmc->clock)
+		return;
+
+	divider = DIV_ROUND_UP(get_PCLK(), mmc->clock);
+	if (divider)
+		divider--;
+
+	writel(divider, &sdi_regs->sdipre);
+	mdelay(125);
+}
+
+static int s3cmmc_init(struct mmc *mmc)
+{
+	struct s3c24x0_clock_power *clk_power = s3c24x0_get_base_clock_power();
+	struct s3c24x0_sdi *sdi_regs = s3c24x0_get_base_sdi();
+
+	/* Start the clock. */
+	setbits_le32(&clk_power->clkcon, 1 << 9);
+
+#if defined(CONFIG_S3C2440)
+	writel(S3C2440_SDICON_SDRESET, &sdi_regs->sdicon);
+	mdelay(10);
+	writel(0x7fffff, &sdi_regs->sdidtimer);
+#else
+	writel(0xffff, &sdi_regs->sdidtimer);
+#endif
+	writel(MMC_MAX_BLOCK_LEN, &sdi_regs->sdibsize);
+	writel(0x0, &sdi_regs->sdiimsk);
+
+	writel(S3C2410_SDICON_FIFORESET | S3C2410_SDICON_CLOCKTYPE,
+	       &sdi_regs->sdicon);
+
+	mdelay(125);
+
+	return 0;
+}
+
+struct s3cmmc_priv {
+	struct mmc_config	cfg;
+	int (*getcd)(struct mmc *);
+	int (*getwp)(struct mmc *);
+};
+
+static int s3cmmc_getcd(struct mmc *mmc)
+{
+	struct s3cmmc_priv *priv = mmc->priv;
+	if (priv->getcd)
+		return priv->getcd(mmc);
+	else
+		return 0;
+}
+
+static int s3cmmc_getwp(struct mmc *mmc)
+{
+	struct s3cmmc_priv *priv = mmc->priv;
+	if (priv->getwp)
+		return priv->getwp(mmc);
+	else
+		return 0;
+}
+
+static const struct mmc_ops s3cmmc_ops = {
+	.send_cmd	= s3cmmc_send_cmd,
+	.set_ios	= s3cmmc_set_ios,
+	.init		= s3cmmc_init,
+	.getcd		= s3cmmc_getcd,
+	.getwp		= s3cmmc_getwp,
+};
+
+int s3cmmc_initialize(bd_t *bis, int (*getcd)(struct mmc *),
+		      int (*getwp)(struct mmc *))
+{
+	struct s3cmmc_priv	*priv;
+	struct mmc		*mmc;
+	struct mmc_config	*cfg;
+
+	priv = calloc(1, sizeof(*priv));
+	if (!priv)
+		return -ENOMEM;
+	cfg = &priv->cfg;
+
+	cfg->name = "S3C MMC";
+	cfg->ops = &s3cmmc_ops;
+	cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+	cfg->host_caps = MMC_MODE_4BIT | MMC_MODE_HC | MMC_MODE_HS;
+	cfg->f_min = 400000;
+	cfg->f_max = get_PCLK() / 2;
+	cfg->b_max = 0x80;
+
+#if defined(CONFIG_S3C2410)
+	/*
+	 * S3C2410 has some bug that prevents reliable
+	 * operation at higher speed
+	 */
+	cfg->f_max /= 2;
+#endif
+
+	mmc = mmc_create(cfg, priv);
+	if (!mmc) {
+		free(priv);
+		return -ENOMEM;
+	}
+
+	return 0;
+}