PXA: Add MMC driver using the generic MMC framework

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>

2 files changed, 443 insertions, 0 deletions

diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 6e948605dce..9f9db751699 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -38,6 +38,7 @@ COBJS-$(CONFIG_MV_SDHCI) += mv_sdhci.o
 COBJS-$(CONFIG_MXC_MMC) += mxcmmc.o
 COBJS-$(CONFIG_OMAP_HSMMC) += omap_hsmmc.o
 COBJS-$(CONFIG_PXA_MMC) += pxa_mmc.o
+COBJS-$(CONFIG_PXA_MMC_GENERIC) += pxa_mmc_gen.o
 COBJS-$(CONFIG_S5P_MMC) += s5p_mmc.o
 COBJS-$(CONFIG_SDHCI) += sdhci.o
 COBJS-$(CONFIG_SH_MMCIF) += sh_mmcif.o
diff --git a/drivers/mmc/pxa_mmc_gen.c b/drivers/mmc/pxa_mmc_gen.c
new file mode 100644
index 00000000000..28e37b4fe1b
--- /dev/null
+++ b/drivers/mmc/pxa_mmc_gen.c
@@ -0,0 +1,442 @@
+/*
+ * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com>
+ *
+ * Loosely based on the old code and Linux's PXA MMC driver
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <config.h>
+#include <common.h>
+#include <malloc.h>
+
+#include <mmc.h>
+#include <asm/errno.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/regs-mmc.h>
+#include <asm/io.h>
+
+/* PXAMMC Generic default config for various CPUs */
+#if defined(CONFIG_PXA250)
+#define PXAMMC_FIFO_SIZE	1
+#define PXAMMC_MIN_SPEED	312500
+#define PXAMMC_MAX_SPEED	20000000
+#define PXAMMC_HOST_CAPS	(0)
+#elif defined(CONFIG_PXA27X)
+#define PXAMMC_CRC_SKIP
+#define PXAMMC_FIFO_SIZE	32
+#define PXAMMC_MIN_SPEED	304000
+#define PXAMMC_MAX_SPEED	19500000
+#define PXAMMC_HOST_CAPS	(MMC_MODE_4BIT)
+#elif defined(CONFIG_CPU_MONAHANS)
+#define PXAMMC_FIFO_SIZE	32
+#define PXAMMC_MIN_SPEED	304000
+#define PXAMMC_MAX_SPEED	26000000
+#define PXAMMC_HOST_CAPS	(MMC_MODE_4BIT | MMC_MODE_HS)
+#else
+#error "This CPU isn't supported by PXA MMC!"
+#endif
+
+#define MMC_STAT_ERRORS							\
+	(MMC_STAT_RES_CRC_ERROR | MMC_STAT_SPI_READ_ERROR_TOKEN |	\
+	MMC_STAT_CRC_READ_ERROR | MMC_STAT_TIME_OUT_RESPONSE |		\
+	MMC_STAT_READ_TIME_OUT | MMC_STAT_CRC_WRITE_ERROR)
+
+/* 1 millisecond (in wait cycles below it's 100 x 10uS waits) */
+#define PXA_MMC_TIMEOUT	100
+
+struct pxa_mmc_priv {
+	struct pxa_mmc_regs *regs;
+};
+
+/* Wait for bit to be set */
+static int pxa_mmc_wait(struct mmc *mmc, uint32_t mask)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	unsigned int timeout = PXA_MMC_TIMEOUT;
+
+	/* Wait for bit to be set */
+	while (--timeout) {
+		if (readl(&regs->stat) & mask)
+			break;
+		udelay(10);
+	}
+
+	if (!timeout)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int pxa_mmc_stop_clock(struct mmc *mmc)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	unsigned int timeout = PXA_MMC_TIMEOUT;
+
+	/* If the clock aren't running, exit */
+	if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
+		return 0;
+
+	/* Tell the controller to turn off the clock */
+	writel(MMC_STRPCL_STOP_CLK, &regs->strpcl);
+
+	/* Wait until the clock are off */
+	while (--timeout) {
+		if (!(readl(&regs->stat) & MMC_STAT_CLK_EN))
+			break;
+		udelay(10);
+	}
+
+	/* The clock refused to stop, scream and die a painful death */
+	if (!timeout)
+		return -ETIMEDOUT;
+
+	/* The clock stopped correctly */
+	return 0;
+}
+
+static int pxa_mmc_start_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
+				uint32_t cmdat)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	int ret;
+
+	/* The card can send a "busy" response */
+	if (cmd->flags & MMC_RSP_BUSY)
+		cmdat |= MMC_CMDAT_BUSY;
+
+	/* Inform the controller about response type */
+	switch (cmd->resp_type) {
+	case MMC_RSP_R1:
+	case MMC_RSP_R1b:
+		cmdat |= MMC_CMDAT_R1;
+		break;
+	case MMC_RSP_R2:
+		cmdat |= MMC_CMDAT_R2;
+		break;
+	case MMC_RSP_R3:
+		cmdat |= MMC_CMDAT_R3;
+		break;
+	default:
+		break;
+	}
+
+	/* Load command and it's arguments into the controller */
+	writel(cmd->cmdidx, &regs->cmd);
+	writel(cmd->cmdarg >> 16, &regs->argh);
+	writel(cmd->cmdarg & 0xffff, &regs->argl);
+	writel(cmdat, &regs->cmdat);
+
+	/* Start the controller clock and wait until they are started */
+	writel(MMC_STRPCL_START_CLK, &regs->strpcl);
+
+	ret = pxa_mmc_wait(mmc, MMC_STAT_CLK_EN);
+	if (ret)
+		return ret;
+
+	/* Correct and happy end */
+	return 0;
+}
+
+static int pxa_mmc_cmd_done(struct mmc *mmc, struct mmc_cmd *cmd)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	uint32_t a, b, c;
+	int i;
+	int stat;
+
+	/* Read the controller status */
+	stat = readl(&regs->stat);
+
+	/*
+	 * Linux says:
+	 * Did I mention this is Sick.  We always need to
+	 * discard the upper 8 bits of the first 16-bit word.
+	 */
+	a = readl(&regs->res) & 0xffff;
+	for (i = 0; i < 4; i++) {
+		b = readl(&regs->res) & 0xffff;
+		c = readl(&regs->res) & 0xffff;
+		cmd->response[i] = (a << 24) | (b << 8) | (c >> 8);
+		a = c;
+	}
+
+	/* The command response didn't arrive */
+	if (stat & MMC_STAT_TIME_OUT_RESPONSE)
+		return -ETIMEDOUT;
+	else if (stat & MMC_STAT_RES_CRC_ERROR && cmd->flags & MMC_RSP_CRC) {
+#ifdef	PXAMMC_CRC_SKIP
+		if (cmd->flags & MMC_RSP_136 && cmd->response[0] & (1 << 31))
+			printf("Ignoring CRC, this may be dangerous!\n");
+		else
+#endif
+		return -EILSEQ;
+	}
+
+	/* The command response was successfully read */
+	return 0;
+}
+
+static int pxa_mmc_do_read_xfer(struct mmc *mmc, struct mmc_data *data)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	uint32_t len;
+	uint32_t *buf = (uint32_t *)data->dest;
+	int size;
+	int ret;
+
+	len = data->blocks * data->blocksize;
+
+	while (len) {
+		/* The controller has data ready */
+		if (readl(&regs->i_reg) & MMC_I_REG_RXFIFO_RD_REQ) {
+			size = min(len, PXAMMC_FIFO_SIZE);
+			len -= size;
+			size /= 4;
+
+			/* Read data into the buffer */
+			while (size--)
+				*buf++ = readl(&regs->rxfifo);
+
+		}
+
+		if (readl(&regs->stat) & MMC_STAT_ERRORS)
+			return -EIO;
+	}
+
+	/* Wait for the transmission-done interrupt */
+	ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int pxa_mmc_do_write_xfer(struct mmc *mmc, struct mmc_data *data)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	uint32_t len;
+	uint32_t *buf = (uint32_t *)data->src;
+	int size;
+	int ret;
+
+	len = data->blocks * data->blocksize;
+
+	while (len) {
+		/* The controller is ready to receive data */
+		if (readl(&regs->i_reg) & MMC_I_REG_TXFIFO_WR_REQ) {
+			size = min(len, PXAMMC_FIFO_SIZE);
+			len -= size;
+			size /= 4;
+
+			while (size--)
+				writel(*buf++, &regs->txfifo);
+
+			if (min(len, PXAMMC_FIFO_SIZE) < 32)
+				writel(MMC_PRTBUF_BUF_PART_FULL, &regs->prtbuf);
+		}
+
+		if (readl(&regs->stat) & MMC_STAT_ERRORS)
+			return -EIO;
+	}
+
+	/* Wait for the transmission-done interrupt */
+	ret = pxa_mmc_wait(mmc, MMC_STAT_DATA_TRAN_DONE);
+	if (ret)
+		return ret;
+
+	/* Wait until the data are really written to the card */
+	ret = pxa_mmc_wait(mmc, MMC_STAT_PRG_DONE);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int pxa_mmc_request(struct mmc *mmc, struct mmc_cmd *cmd,
+				struct mmc_data *data)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	uint32_t cmdat = 0;
+	int ret;
+
+	/* Stop the controller */
+	ret = pxa_mmc_stop_clock(mmc);
+	if (ret)
+		return ret;
+
+	/* If we're doing data transfer, configure the controller accordingly */
+	if (data) {
+		writel(data->blocks, &regs->nob);
+		writel(data->blocksize, &regs->blklen);
+		/* This delay can be optimized, but stick with max value */
+		writel(0xffff, &regs->rdto);
+		cmdat |= MMC_CMDAT_DATA_EN;
+		if (data->flags & MMC_DATA_WRITE)
+			cmdat |= MMC_CMDAT_WRITE;
+	}
+
+	/* Run in 4bit mode if the card can do it */
+	if (mmc->bus_width == 4)
+		cmdat |= MMC_CMDAT_SD_4DAT;
+
+	/* Execute the command */
+	ret = pxa_mmc_start_cmd(mmc, cmd, cmdat);
+	if (ret)
+		return ret;
+
+	/* Wait until the command completes */
+	ret = pxa_mmc_wait(mmc, MMC_STAT_END_CMD_RES);
+	if (ret)
+		return ret;
+
+	/* Read back the result */
+	ret = pxa_mmc_cmd_done(mmc, cmd);
+	if (ret)
+		return ret;
+
+	/* In case there was a data transfer scheduled, do it */
+	if (data) {
+		if (data->flags & MMC_DATA_WRITE)
+			pxa_mmc_do_write_xfer(mmc, data);
+		else
+			pxa_mmc_do_read_xfer(mmc, data);
+	}
+
+	return 0;
+}
+
+static void pxa_mmc_set_ios(struct mmc *mmc)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+	uint32_t tmp;
+	uint32_t pxa_mmc_clock;
+
+	if (!mmc->clock) {
+		pxa_mmc_stop_clock(mmc);
+		return;
+	}
+
+	/* PXA3xx can do 26MHz with special settings. */
+	if (mmc->clock == 26000000) {
+		writel(0x7, &regs->clkrt);
+		return;
+	}
+
+	/* Set clock to the card the usual way. */
+	pxa_mmc_clock = 0;
+	tmp = mmc->f_max / mmc->clock;
+	tmp += tmp % 2;
+
+	while (tmp > 1) {
+		pxa_mmc_clock++;
+		tmp >>= 1;
+	}
+
+	writel(pxa_mmc_clock, &regs->clkrt);
+}
+
+static int pxa_mmc_init(struct mmc *mmc)
+{
+	struct pxa_mmc_priv *priv = (struct pxa_mmc_priv *)mmc->priv;
+	struct pxa_mmc_regs *regs = priv->regs;
+
+	/* Make sure the clock are stopped */
+	pxa_mmc_stop_clock(mmc);
+
+	/* Turn off SPI mode */
+	writel(0, &regs->spi);
+
+	/* Set up maximum timeout to wait for command response */
+	writel(MMC_RES_TO_MAX_MASK, &regs->resto);
+
+	/* Mask all interrupts */
+	writel(~(MMC_I_MASK_TXFIFO_WR_REQ | MMC_I_MASK_RXFIFO_RD_REQ),
+		&regs->i_mask);
+	return 0;
+}
+
+int pxa_mmc_register(int card_index)
+{
+	struct mmc *mmc;
+	struct pxa_mmc_priv *priv;
+	uint32_t reg;
+	int ret = -ENOMEM;
+
+	mmc = malloc(sizeof(struct mmc));
+	if (!mmc)
+		goto err0;
+
+	priv = malloc(sizeof(struct pxa_mmc_priv));
+	if (!priv)
+		goto err1;
+
+	switch (card_index) {
+	case 0:
+		priv->regs = (struct pxa_mmc_regs *)MMC0_BASE;
+		break;
+	case 1:
+		priv->regs = (struct pxa_mmc_regs *)MMC1_BASE;
+		break;
+	default:
+		printf("PXA MMC: Invalid MMC controller ID (card_index = %d)\n",
+			card_index);
+		goto err2;
+	}
+
+	mmc->priv = priv;
+
+	sprintf(mmc->name, "PXA MMC");
+	mmc->send_cmd	= pxa_mmc_request;
+	mmc->set_ios	= pxa_mmc_set_ios;
+	mmc->init	= pxa_mmc_init;
+
+	mmc->voltages	= MMC_VDD_32_33 | MMC_VDD_33_34;
+	mmc->f_max	= PXAMMC_MAX_SPEED;
+	mmc->f_min	= PXAMMC_MIN_SPEED;
+	mmc->host_caps	= PXAMMC_HOST_CAPS;
+
+	mmc->b_max = 0;
+
+#ifndef	CONFIG_CPU_MONAHANS	/* PXA2xx */
+	reg = readl(CKEN);
+	reg |= CKEN12_MMC;
+	writel(reg, CKEN);
+#else				/* PXA3xx */
+	reg = readl(CKENA);
+	reg |= CKENA_12_MMC0 | CKENA_13_MMC1;
+	writel(reg, CKENA);
+#endif
+
+	mmc_register(mmc);
+
+	return 0;
+
+err2:
+	free(priv);
+err1:
+	free(mmc);
+err0:
+	return ret;
+}