iMX28: Add SSP MMC driver
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Andy Fleming <afleming@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Detlev Zundel <dzu@denx.de>
Acked-by: Andy Fleming <afleming@gmail.com>
diff --git a/drivers/mmc/mxsmmc.c b/drivers/mmc/mxsmmc.c
new file mode 100644
index 0000000..2a9949e
--- /dev/null
+++ b/drivers/mmc/mxsmmc.c
@@ -0,0 +1,351 @@
+/*
+ * Freescale i.MX28 SSP MMC driver
+ *
+ * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
+ * on behalf of DENX Software Engineering GmbH
+ *
+ * Based on code from LTIB:
+ * (C) Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Terry Lv
+ *
+ * Copyright 2007, Freescale Semiconductor, Inc
+ * Andy Fleming
+ *
+ * Based vaguely on the pxa mmc code:
+ * (C) Copyright 2003
+ * Kyle Harris, Nexus Technologies, Inc. kharris@nexus-tech.net
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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 <common.h>
+#include <malloc.h>
+#include <mmc.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/imx-regs.h>
+#include <asm/arch/sys_proto.h>
+
+struct mxsmmc_priv {
+ int id;
+ struct mx28_ssp_regs *regs;
+ uint32_t clkseq_bypass;
+ uint32_t *clkctrl_ssp;
+ uint32_t buswidth;
+ int (*mmc_is_wp)(int);
+};
+
+#define MXSMMC_MAX_TIMEOUT 10000
+
+/*
+ * Sends a command out on the bus. Takes the mmc pointer,
+ * a command pointer, and an optional data pointer.
+ */
+static int
+mxsmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
+{
+ struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
+ struct mx28_ssp_regs *ssp_regs = priv->regs;
+ uint32_t reg;
+ int timeout;
+ uint32_t data_count;
+ uint32_t *data_ptr;
+ uint32_t ctrl0;
+
+ debug("MMC%d: CMD%d\n", mmc->block_dev.dev, cmd->cmdidx);
+
+ /* Check bus busy */
+ timeout = MXSMMC_MAX_TIMEOUT;
+ while (--timeout) {
+ udelay(1000);
+ reg = readl(&ssp_regs->hw_ssp_status);
+ if (!(reg &
+ (SSP_STATUS_BUSY | SSP_STATUS_DATA_BUSY |
+ SSP_STATUS_CMD_BUSY))) {
+ break;
+ }
+ }
+
+ if (!timeout) {
+ printf("MMC%d: Bus busy timeout!\n", mmc->block_dev.dev);
+ return TIMEOUT;
+ }
+
+ /* See if card is present */
+ if (readl(&ssp_regs->hw_ssp_status) & SSP_STATUS_CARD_DETECT) {
+ printf("MMC%d: No card detected!\n", mmc->block_dev.dev);
+ return NO_CARD_ERR;
+ }
+
+ /* Start building CTRL0 contents */
+ ctrl0 = priv->buswidth;
+
+ /* Set up command */
+ if (!(cmd->resp_type & MMC_RSP_CRC))
+ ctrl0 |= SSP_CTRL0_IGNORE_CRC;
+ if (cmd->resp_type & MMC_RSP_PRESENT) /* Need to get response */
+ ctrl0 |= SSP_CTRL0_GET_RESP;
+ if (cmd->resp_type & MMC_RSP_136) /* It's a 136 bits response */
+ ctrl0 |= SSP_CTRL0_LONG_RESP;
+
+ /* Command index */
+ reg = readl(&ssp_regs->hw_ssp_cmd0);
+ reg &= ~(SSP_CMD0_CMD_MASK | SSP_CMD0_APPEND_8CYC);
+ reg |= cmd->cmdidx << SSP_CMD0_CMD_OFFSET;
+ if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
+ reg |= SSP_CMD0_APPEND_8CYC;
+ writel(reg, &ssp_regs->hw_ssp_cmd0);
+
+ /* Command argument */
+ writel(cmd->cmdarg, &ssp_regs->hw_ssp_cmd1);
+
+ /* Set up data */
+ if (data) {
+ /* READ or WRITE */
+ if (data->flags & MMC_DATA_READ) {
+ ctrl0 |= SSP_CTRL0_READ;
+ } else if (priv->mmc_is_wp(mmc->block_dev.dev)) {
+ printf("MMC%d: Can not write a locked card!\n",
+ mmc->block_dev.dev);
+ return UNUSABLE_ERR;
+ }
+
+ ctrl0 |= SSP_CTRL0_DATA_XFER;
+ reg = ((data->blocks - 1) <<
+ SSP_BLOCK_SIZE_BLOCK_COUNT_OFFSET) |
+ ((ffs(data->blocksize) - 1) <<
+ SSP_BLOCK_SIZE_BLOCK_SIZE_OFFSET);
+ writel(reg, &ssp_regs->hw_ssp_block_size);
+
+ reg = data->blocksize * data->blocks;
+ writel(reg, &ssp_regs->hw_ssp_xfer_size);
+ }
+
+ /* Kick off the command */
+ ctrl0 |= SSP_CTRL0_WAIT_FOR_IRQ | SSP_CTRL0_ENABLE | SSP_CTRL0_RUN;
+ writel(ctrl0, &ssp_regs->hw_ssp_ctrl0);
+
+ /* Wait for the command to complete */
+ timeout = MXSMMC_MAX_TIMEOUT;
+ while (--timeout) {
+ udelay(1000);
+ reg = readl(&ssp_regs->hw_ssp_status);
+ if (!(reg & SSP_STATUS_CMD_BUSY))
+ break;
+ }
+
+ if (!timeout) {
+ printf("MMC%d: Command %d busy\n",
+ mmc->block_dev.dev, cmd->cmdidx);
+ return TIMEOUT;
+ }
+
+ /* Check command timeout */
+ if (reg & SSP_STATUS_RESP_TIMEOUT) {
+ printf("MMC%d: Command %d timeout (status 0x%08x)\n",
+ mmc->block_dev.dev, cmd->cmdidx, reg);
+ return TIMEOUT;
+ }
+
+ /* Check command errors */
+ if (reg & (SSP_STATUS_RESP_CRC_ERR | SSP_STATUS_RESP_ERR)) {
+ printf("MMC%d: Command %d error (status 0x%08x)!\n",
+ mmc->block_dev.dev, cmd->cmdidx, reg);
+ return COMM_ERR;
+ }
+
+ /* Copy response to response buffer */
+ if (cmd->resp_type & MMC_RSP_136) {
+ cmd->response[3] = readl(&ssp_regs->hw_ssp_sdresp0);
+ cmd->response[2] = readl(&ssp_regs->hw_ssp_sdresp1);
+ cmd->response[1] = readl(&ssp_regs->hw_ssp_sdresp2);
+ cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp3);
+ } else
+ cmd->response[0] = readl(&ssp_regs->hw_ssp_sdresp0);
+
+ /* Return if no data to process */
+ if (!data)
+ return 0;
+
+ /* Process the data */
+ data_count = data->blocksize * data->blocks;
+ timeout = MXSMMC_MAX_TIMEOUT;
+ if (data->flags & MMC_DATA_READ) {
+ data_ptr = (uint32_t *)data->dest;
+ while (data_count && --timeout) {
+ reg = readl(&ssp_regs->hw_ssp_status);
+ if (!(reg & SSP_STATUS_FIFO_EMPTY)) {
+ *data_ptr++ = readl(&ssp_regs->hw_ssp_data);
+ data_count -= 4;
+ timeout = MXSMMC_MAX_TIMEOUT;
+ } else
+ udelay(1000);
+ }
+ } else {
+ data_ptr = (uint32_t *)data->src;
+ timeout *= 100;
+ while (data_count && --timeout) {
+ reg = readl(&ssp_regs->hw_ssp_status);
+ if (!(reg & SSP_STATUS_FIFO_FULL)) {
+ writel(*data_ptr++, &ssp_regs->hw_ssp_data);
+ data_count -= 4;
+ timeout = MXSMMC_MAX_TIMEOUT;
+ } else
+ udelay(1000);
+ }
+ }
+
+ if (!timeout) {
+ printf("MMC%d: Data timeout with command %d (status 0x%08x)!\n",
+ mmc->block_dev.dev, cmd->cmdidx, reg);
+ return COMM_ERR;
+ }
+
+ /* Check data errors */
+ reg = readl(&ssp_regs->hw_ssp_status);
+ if (reg &
+ (SSP_STATUS_TIMEOUT | SSP_STATUS_DATA_CRC_ERR |
+ SSP_STATUS_FIFO_OVRFLW | SSP_STATUS_FIFO_UNDRFLW)) {
+ printf("MMC%d: Data error with command %d (status 0x%08x)!\n",
+ mmc->block_dev.dev, cmd->cmdidx, reg);
+ return COMM_ERR;
+ }
+
+ return 0;
+}
+
+static void mxsmmc_set_ios(struct mmc *mmc)
+{
+ struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
+ struct mx28_ssp_regs *ssp_regs = priv->regs;
+
+ /* Set the clock speed */
+ if (mmc->clock)
+ mx28_set_ssp_busclock(priv->id, mmc->clock / 1000);
+
+ switch (mmc->bus_width) {
+ case 1:
+ priv->buswidth = SSP_CTRL0_BUS_WIDTH_ONE_BIT;
+ break;
+ case 4:
+ priv->buswidth = SSP_CTRL0_BUS_WIDTH_FOUR_BIT;
+ break;
+ case 8:
+ priv->buswidth = SSP_CTRL0_BUS_WIDTH_EIGHT_BIT;
+ break;
+ }
+
+ /* Set the bus width */
+ clrsetbits_le32(&ssp_regs->hw_ssp_ctrl0,
+ SSP_CTRL0_BUS_WIDTH_MASK, priv->buswidth);
+
+ debug("MMC%d: Set %d bits bus width\n",
+ mmc->block_dev.dev, mmc->bus_width);
+}
+
+static int mxsmmc_init(struct mmc *mmc)
+{
+ struct mxsmmc_priv *priv = (struct mxsmmc_priv *)mmc->priv;
+ struct mx28_ssp_regs *ssp_regs = priv->regs;
+
+ /* Reset SSP */
+ mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
+
+ /* 8 bits word length in MMC mode */
+ clrsetbits_le32(&ssp_regs->hw_ssp_ctrl1,
+ SSP_CTRL1_SSP_MODE_MASK | SSP_CTRL1_WORD_LENGTH_MASK,
+ SSP_CTRL1_SSP_MODE_SD_MMC | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS);
+
+ /* Set initial bit clock 400 KHz */
+ mx28_set_ssp_busclock(priv->id, 400);
+
+ /* Send initial 74 clock cycles (185 us @ 400 KHz)*/
+ writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_set);
+ udelay(200);
+ writel(SSP_CMD0_CONT_CLKING_EN, &ssp_regs->hw_ssp_cmd0_clr);
+
+ return 0;
+}
+
+int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int))
+{
+ struct mx28_clkctrl_regs *clkctrl_regs =
+ (struct mx28_clkctrl_regs *)MXS_CLKCTRL_BASE;
+ struct mmc *mmc = NULL;
+ struct mxsmmc_priv *priv = NULL;
+
+ mmc = malloc(sizeof(struct mmc));
+ if (!mmc)
+ return -ENOMEM;
+
+ priv = malloc(sizeof(struct mxsmmc_priv));
+ if (!priv) {
+ free(mmc);
+ return -ENOMEM;
+ }
+
+ priv->mmc_is_wp = wp;
+ priv->id = id;
+ switch (id) {
+ case 0:
+ priv->regs = (struct mx28_ssp_regs *)MXS_SSP0_BASE;
+ priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP0;
+ priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp0;
+ break;
+ case 1:
+ priv->regs = (struct mx28_ssp_regs *)MXS_SSP1_BASE;
+ priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP1;
+ priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp1;
+ break;
+ case 2:
+ priv->regs = (struct mx28_ssp_regs *)MXS_SSP2_BASE;
+ priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP2;
+ priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp2;
+ break;
+ case 3:
+ priv->regs = (struct mx28_ssp_regs *)MXS_SSP3_BASE;
+ priv->clkseq_bypass = CLKCTRL_CLKSEQ_BYPASS_SSP3;
+ priv->clkctrl_ssp = &clkctrl_regs->hw_clkctrl_ssp3;
+ break;
+ }
+
+ sprintf(mmc->name, "MXS MMC");
+ mmc->send_cmd = mxsmmc_send_cmd;
+ mmc->set_ios = mxsmmc_set_ios;
+ mmc->init = mxsmmc_init;
+ mmc->priv = priv;
+
+ mmc->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+ mmc->host_caps = MMC_MODE_4BIT | MMC_MODE_8BIT |
+ MMC_MODE_HS_52MHz | MMC_MODE_HS;
+
+ /*
+ * SSPCLK = 480 * 18 / 29 / 1 = 297.731 MHz
+ * SSP bit rate = SSPCLK / (CLOCK_DIVIDE * (1 + CLOCK_RATE)),
+ * CLOCK_DIVIDE has to be an even value from 2 to 254, and
+ * CLOCK_RATE could be any integer from 0 to 255.
+ */
+ mmc->f_min = 400000;
+ mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2;
+ mmc->b_max = 0;
+
+ mmc_register(mmc);
+ return 0;
+}