Au1[12]00 mmc driver. Only tested on the Au1200 at this point though

it should work on the Au1100 as well. Updated defconfig to include driver.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

5 files changed, 1166 insertions, 0 deletions

diff --git a/arch/mips/au1000/common/platform.c b/arch/mips/au1000/common/platform.c
index 0f29815003fa..efb00fc5640e 100644
--- a/arch/mips/au1000/common/platform.c
+++ b/arch/mips/au1000/common/platform.c
@@ -7,6 +7,7 @@
  * License version 2.  This program is licensed "as is" without any
  * warranty of any kind, whether express or implied.
  */
+#include <linux/config.h>
 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
@@ -114,6 +115,24 @@ static struct resource au1xxx_usb_gdt_resources[] = {
         },
 };
 
+static struct resource au1xxx_mmc_resources[] = {
+        [0] = {
+                .start          = SD0_PHYS_ADDR,
+                .end            = SD0_PHYS_ADDR + 0x40,
+                .flags          = IORESOURCE_MEM,
+        },
+        [1] = {
+                .start          = SD1_PHYS_ADDR,
+                .end            = SD1_PHYS_ADDR + 0x40,
+                .flags          = IORESOURCE_MEM,
+        },
+        [2] = {
+                .start          = AU1200_SD_INT,
+                .end            = AU1200_SD_INT,
+                .flags          = IORESOURCE_IRQ,
+        }
+};
+
 static u64 udc_dmamask = ~(u32)0;
 
 static struct platform_device au1xxx_usb_gdt_device = {
@@ -207,6 +226,20 @@ static struct platform_device au1200_ide0_device = {
         .resource       = au1200_ide0_resources,
 };
 
+static u64 au1xxx_mmc_dmamask =  ~(u32)0;
+
+static struct platform_device au1xxx_mmc_device = {
+        .name = "au1xxx-mmc",
+        .id = 0,
+        .dev = {
+                .dma_mask               = &au1xxx_mmc_dmamask,
+                .coherent_dma_mask      = 0xffffffff,
+        },
+        .num_resources  = ARRAY_SIZE(au1xxx_mmc_resources),
+        .resource       = au1xxx_mmc_resources,
+};
+#endif /* #ifdef CONFIG_SOC_AU1200 */
+
 static struct platform_device au1x00_pcmcia_device = {
         .name           = "au1x00-pcmcia",
         .id             = 0,
@@ -226,6 +259,7 @@ static struct platform_device *au1xxx_platform_devices[] __initdata = {
         &au1xxx_usb_otg_device,
         &au1200_lcd_device,
         &au1200_ide0_device,
+        &au1xxx_mmc_device,
 #endif
 };
 
diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig
index 4991bbd054f3..c483a863b116 100644
--- a/drivers/mmc/Kconfig
+++ b/drivers/mmc/Kconfig
@@ -60,4 +60,13 @@ config MMC_WBSD
 
           If unsure, say N.
 
+config MMC_AU1X
+        tristate "Alchemy AU1XX0 MMC Card Interface support"
+        depends on SOC_AU1X00 && MMC
+        help
+          This selects the AMD Alchemy(R) Multimedia card interface.
+          iIf you have a Alchemy platform with a MMC slot, say Y or M here.
+
+          If unsure, say N.
+
 endmenu
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 89510c2086c7..e351e71146e9 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -18,5 +18,6 @@ obj-$(CONFIG_MMC_BLOCK)		+= mmc_block.o
 obj-$(CONFIG_MMC_ARMMMCI)       += mmci.o
 obj-$(CONFIG_MMC_PXA)           += pxamci.o
 obj-$(CONFIG_MMC_WBSD)          += wbsd.o
+obj-$(CONFIG_MMC_AU1X)          += au1xmmc.o
 
 mmc_core-y := mmc.o mmc_queue.o mmc_sysfs.o
diff --git a/drivers/mmc/au1xmmc.c b/drivers/mmc/au1xmmc.c
new file mode 100644
index 000000000000..aaf04638054e
--- /dev/null
+++ b/drivers/mmc/au1xmmc.c
@@ -0,0 +1,1026 @@
+/*
+ * linux/drivers/mmc/au1xmmc.c - AU1XX0 MMC driver
+ *
+ *  Copyright (c) 2005, Advanced Micro Devices, Inc.
+ *
+ *  Developed with help from the 2.4.30 MMC AU1XXX controller including
+ *  the following copyright notices:
+ *     Copyright (c) 2003-2004 Embedded Edge, LLC.
+ *     Portions Copyright (C) 2002 Embedix, Inc
+ *     Copyright 2002 Hewlett-Packard Company
+
+ *  2.6 version of this driver inspired by:
+ *     (drivers/mmc/wbsd.c) Copyright (C) 2004-2005 Pierre Ossman,
+ *     All Rights Reserved.
+ *     (drivers/mmc/pxa.c) Copyright (C) 2003 Russell King,
+ *     All Rights Reserved.
+ *
+
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* Why is a timer used to detect insert events?
+ *
+ * From the AU1100 MMC application guide:
+ * If the Au1100-based design is intended to support both MultiMediaCards
+ * and 1- or 4-data bit SecureDigital cards, then the solution is to
+ * connect a weak (560KOhm) pull-up resistor to connector pin 1.
+ * In doing so, a MMC card never enters SPI-mode communications,
+ * but now the SecureDigital card-detect feature of CD/DAT3 is ineffective
+ * (the low to high transition will not occur).
+ *
+ * So we use the timer to check the status manually.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+
+#include <linux/mmc/host.h>
+#include <linux/mmc/protocol.h>
+#include <asm/io.h>
+#include <asm/mach-au1x00/au1000.h>
+#include <asm/mach-au1x00/au1xxx_dbdma.h>
+#include <asm/mach-au1x00/au1100_mmc.h>
+#include <asm/scatterlist.h>
+
+#include <au1xxx.h>
+#include "au1xmmc.h"
+
+#define DRIVER_NAME "au1xxx-mmc"
+
+/* Set this to enable special debugging macros */
+/* #define MMC_DEBUG */
+
+#ifdef MMC_DEBUG
+#define DEBUG(fmt, idx, args...) printk("au1xx(%d): DEBUG: " fmt, idx, ##args)
+#else
+#define DEBUG(fmt, idx, args...)
+#endif
+
+const struct {
+        u32 iobase;
+        u32 tx_devid, rx_devid;
+        u16 bcsrpwr;
+        u16 bcsrstatus;
+        u16 wpstatus;
+} au1xmmc_card_table[] = {
+        { SD0_BASE, DSCR_CMD0_SDMS_TX0, DSCR_CMD0_SDMS_RX0,
+          BCSR_BOARD_SD0PWR, BCSR_INT_SD0INSERT, BCSR_STATUS_SD0WP },
+#ifndef CONFIG_MIPS_DB1200
+        { SD1_BASE, DSCR_CMD0_SDMS_TX1, DSCR_CMD0_SDMS_RX1,
+          BCSR_BOARD_DS1PWR, BCSR_INT_SD1INSERT, BCSR_STATUS_SD1WP }
+#endif
+};
+
+#define AU1XMMC_CONTROLLER_COUNT \
+        (sizeof(au1xmmc_card_table) / sizeof(au1xmmc_card_table[0]))
+
+/* This array stores pointers for the hosts (used by the IRQ handler) */
+struct au1xmmc_host *au1xmmc_hosts[AU1XMMC_CONTROLLER_COUNT];
+static int dma = 1;
+
+#ifdef MODULE
+MODULE_PARM(dma, "i");
+MODULE_PARM_DESC(dma, "Use DMA engine for data transfers (0 = disabled)");
+#endif
+
+static inline void IRQ_ON(struct au1xmmc_host *host, u32 mask)
+{
+        u32 val = au_readl(HOST_CONFIG(host));
+        val |= mask;
+        au_writel(val, HOST_CONFIG(host));
+        au_sync();
+}
+
+static inline void FLUSH_FIFO(struct au1xmmc_host *host)
+{
+        u32 val = au_readl(HOST_CONFIG2(host));
+
+        au_writel(val | SD_CONFIG2_FF, HOST_CONFIG2(host));
+        au_sync_delay(1);
+
+        /* SEND_STOP will turn off clock control - this re-enables it */
+        val &= ~SD_CONFIG2_DF;
+
+        au_writel(val, HOST_CONFIG2(host));
+        au_sync();
+}
+
+static inline void IRQ_OFF(struct au1xmmc_host *host, u32 mask)
+{
+        u32 val = au_readl(HOST_CONFIG(host));
+        val &= ~mask;
+        au_writel(val, HOST_CONFIG(host));
+        au_sync();
+}
+
+static inline void SEND_STOP(struct au1xmmc_host *host)
+{
+
+        /* We know the value of CONFIG2, so avoid a read we don't need */
+        u32 mask = SD_CONFIG2_EN;
+
+        WARN_ON(host->status != HOST_S_DATA);
+        host->status = HOST_S_STOP;
+
+        au_writel(mask | SD_CONFIG2_DF, HOST_CONFIG2(host));
+        au_sync();
+
+        /* Send the stop commmand */
+        au_writel(STOP_CMD, HOST_CMD(host));
+}
+
+static void au1xmmc_set_power(struct au1xmmc_host *host, int state)
+{
+
+        u32 val = au1xmmc_card_table[host->id].bcsrpwr;
+
+        bcsr->board &= ~val;
+        if (state) bcsr->board |= val;
+
+        au_sync_delay(1);
+}
+
+static inline int au1xmmc_card_inserted(struct au1xmmc_host *host)
+{
+        return (bcsr->sig_status & au1xmmc_card_table[host->id].bcsrstatus)
+                ? 1 : 0;
+}
+
+static inline int au1xmmc_card_readonly(struct au1xmmc_host *host)
+{
+        return (bcsr->status & au1xmmc_card_table[host->id].wpstatus)
+                ? 1 : 0;
+}
+
+static void au1xmmc_finish_request(struct au1xmmc_host *host)
+{
+
+        struct mmc_request *mrq = host->mrq;
+
+        host->mrq = NULL;
+        host->flags &= HOST_F_ACTIVE;
+
+        host->dma.len = 0;
+        host->dma.dir = 0;
+
+        host->pio.index  = 0;
+        host->pio.offset = 0;
+        host->pio.len = 0;
+
+        host->status = HOST_S_IDLE;
+
+        bcsr->disk_leds |= (1 << 8);
+
+        mmc_request_done(host->mmc, mrq);
+}
+
+static void au1xmmc_tasklet_finish(unsigned long param)
+{
+        struct au1xmmc_host *host = (struct au1xmmc_host *) param;
+        au1xmmc_finish_request(host);
+}
+
+static int au1xmmc_send_command(struct au1xmmc_host *host, int wait,
+                                struct mmc_command *cmd)
+{
+
+        u32 mmccmd = (cmd->opcode << SD_CMD_CI_SHIFT);
+
+        switch(cmd->flags) {
+        case MMC_RSP_R1:
+                mmccmd |= SD_CMD_RT_1;
+                break;
+        case MMC_RSP_R1B:
+                mmccmd |= SD_CMD_RT_1B;
+                break;
+        case MMC_RSP_R2:
+                mmccmd |= SD_CMD_RT_2;
+                break;
+        case MMC_RSP_R3:
+                mmccmd |= SD_CMD_RT_3;
+                break;
+        }
+
+        switch(cmd->opcode) {
+        case MMC_READ_SINGLE_BLOCK:
+        case SD_APP_SEND_SCR:
+                mmccmd |= SD_CMD_CT_2;
+                break;
+        case MMC_READ_MULTIPLE_BLOCK:
+                mmccmd |= SD_CMD_CT_4;
+                break;
+        case MMC_WRITE_BLOCK:
+                mmccmd |= SD_CMD_CT_1;
+                break;
+
+        case MMC_WRITE_MULTIPLE_BLOCK:
+                mmccmd |= SD_CMD_CT_3;
+                break;
+        case MMC_STOP_TRANSMISSION:
+                mmccmd |= SD_CMD_CT_7;
+                break;
+        }
+
+        au_writel(cmd->arg, HOST_CMDARG(host));
+        au_sync();
+
+        if (wait)
+                IRQ_OFF(host, SD_CONFIG_CR);
+
+        au_writel((mmccmd | SD_CMD_GO), HOST_CMD(host));
+        au_sync();
+
+        /* Wait for the command to go on the line */
+
+        while(1) {
+                if (!(au_readl(HOST_CMD(host)) & SD_CMD_GO))
+                        break;
+        }
+
+        /* Wait for the command to come back */
+
+        if (wait) {
+                u32 status = au_readl(HOST_STATUS(host));
+
+                while(!(status & SD_STATUS_CR))
+                        status = au_readl(HOST_STATUS(host));
+
+                /* Clear the CR status */
+                au_writel(SD_STATUS_CR, HOST_STATUS(host));
+
+                IRQ_ON(host, SD_CONFIG_CR);
+        }
+
+        return MMC_ERR_NONE;
+}
+
+static void au1xmmc_data_complete(struct au1xmmc_host *host, u32 status)
+{
+
+        struct mmc_request *mrq = host->mrq;
+        struct mmc_data *data;
+        u32 crc;
+
+        WARN_ON(host->status != HOST_S_DATA && host->status != HOST_S_STOP);
+
+        if (host->mrq == NULL)
+                return;
+
+        data = mrq->cmd->data;
+
+        if (status == 0)
+                status = au_readl(HOST_STATUS(host));
+
+        /* The transaction is really over when the SD_STATUS_DB bit is clear */
+
+        while((host->flags & HOST_F_XMIT) && (status & SD_STATUS_DB))
+                status = au_readl(HOST_STATUS(host));
+
+        data->error = MMC_ERR_NONE;
+        dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, host->dma.dir);
+
+        /* Process any errors */
+
+        crc = (status & (SD_STATUS_WC | SD_STATUS_RC));
+        if (host->flags & HOST_F_XMIT)
+                crc |= ((status & 0x07) == 0x02) ? 0 : 1;
+
+        if (crc)
+                data->error = MMC_ERR_BADCRC;
+
+        /* Clear the CRC bits */
+        au_writel(SD_STATUS_WC | SD_STATUS_RC, HOST_STATUS(host));
+
+        data->bytes_xfered = 0;
+
+        if (data->error == MMC_ERR_NONE) {
+                if (host->flags & HOST_F_DMA) {
+                        u32 chan = DMA_CHANNEL(host);
+
+                        chan_tab_t *c = *((chan_tab_t **) chan);
+                        au1x_dma_chan_t *cp = c->chan_ptr;
+                        data->bytes_xfered = cp->ddma_bytecnt;
+                }
+                else
+                        data->bytes_xfered =
+                                (data->blocks * (1 << data->blksz_bits)) -
+                                host->pio.len;
+        }
+
+        au1xmmc_finish_request(host);
+}
+
+static void au1xmmc_tasklet_data(unsigned long param)
+{
+        struct au1xmmc_host *host = (struct au1xmmc_host *) param;
+
+        u32 status = au_readl(HOST_STATUS(host));
+        au1xmmc_data_complete(host, status);
+}
+
+#define AU1XMMC_MAX_TRANSFER 8
+
+static void au1xmmc_send_pio(struct au1xmmc_host *host)
+{
+
+        struct mmc_data *data = 0;
+        int sg_len, max, count = 0;
+        unsigned char *sg_ptr;
+        u32 status = 0;
+        struct scatterlist *sg;
+
+        data = host->mrq->data;
+
+        if (!(host->flags & HOST_F_XMIT))
+                return;
+
+        /* This is the pointer to the data buffer */
+        sg = &data->sg[host->pio.index];
+        sg_ptr = page_address(sg->page) + sg->offset + host->pio.offset;
+
+        /* This is the space left inside the buffer */
+        sg_len = data->sg[host->pio.index].length - host->pio.offset;
+
+        /* Check to if we need less then the size of the sg_buffer */
+
+        max = (sg_len > host->pio.len) ? host->pio.len : sg_len;
+        if (max > AU1XMMC_MAX_TRANSFER) max = AU1XMMC_MAX_TRANSFER;
+
+        for(count = 0; count < max; count++ ) {
+                unsigned char val;
+
+                status = au_readl(HOST_STATUS(host));
+
+                if (!(status & SD_STATUS_TH))
+                        break;
+
+                val = *sg_ptr++;
+
+                au_writel((unsigned long) val, HOST_TXPORT(host));
+                au_sync();
+        }
+
+        host->pio.len -= count;
+        host->pio.offset += count;
+
+        if (count == sg_len) {
+                host->pio.index++;
+                host->pio.offset = 0;
+        }
+
+        if (host->pio.len == 0) {
+                IRQ_OFF(host, SD_CONFIG_TH);
+
+                if (host->flags & HOST_F_STOP)
+                        SEND_STOP(host);
+
+                tasklet_schedule(&host->data_task);
+        }
+}
+
+static void au1xmmc_receive_pio(struct au1xmmc_host *host)
+{
+
+        struct mmc_data *data = 0;
+        int sg_len = 0, max = 0, count = 0;
+        unsigned char *sg_ptr = 0;
+        u32 status = 0;
+        struct scatterlist *sg;
+
+        data = host->mrq->data;
+
+        if (!(host->flags & HOST_F_RECV))
+                return;
+
+        max = host->pio.len;
+
+        if (host->pio.index < host->dma.len) {
+                sg = &data->sg[host->pio.index];
+                sg_ptr = page_address(sg->page) + sg->offset + host->pio.offset;
+
+                /* This is the space left inside the buffer */
+                sg_len = sg_dma_len(&data->sg[host->pio.index]) - host->pio.offset;
+
+                /* Check to if we need less then the size of the sg_buffer */
+                if (sg_len < max) max = sg_len;
+        }
+
+        if (max > AU1XMMC_MAX_TRANSFER)
+                max = AU1XMMC_MAX_TRANSFER;
+
+        for(count = 0; count < max; count++ ) {
+                u32 val;
+                status = au_readl(HOST_STATUS(host));
+
+                if (!(status & SD_STATUS_NE))
+                        break;
+
+                if (status & SD_STATUS_RC) {
+                        DEBUG("RX CRC Error [%d + %d].\n", host->id,
+                                        host->pio.len, count);
+                        break;
+                }
+
+                if (status & SD_STATUS_RO) {
+                        DEBUG("RX Overrun [%d + %d]\n", host->id,
+                                        host->pio.len, count);
+                        break;
+                }
+                else if (status & SD_STATUS_RU) {
+                        DEBUG("RX Underrun [%d + %d]\n", host->id,
+                                        host->pio.len,  count);
+                        break;
+                }
+
+                val = au_readl(HOST_RXPORT(host));
+
+                if (sg_ptr)
+                        *sg_ptr++ = (unsigned char) (val & 0xFF);
+        }
+
+        host->pio.len -= count;
+        host->pio.offset += count;
+
+        if (sg_len && count == sg_len) {
+                host->pio.index++;
+                host->pio.offset = 0;
+        }
+
+        if (host->pio.len == 0) {
+                //IRQ_OFF(host, SD_CONFIG_RA | SD_CONFIG_RF);
+                IRQ_OFF(host, SD_CONFIG_NE);
+
+                if (host->flags & HOST_F_STOP)
+                        SEND_STOP(host);
+
+                tasklet_schedule(&host->data_task);
+        }
+}
+
+/* static void au1xmmc_cmd_complete
+   This is called when a command has been completed - grab the response
+   and check for errors.  Then start the data transfer if it is indicated.
+*/
+
+static void au1xmmc_cmd_complete(struct au1xmmc_host *host, u32 status)
+{
+
+        struct mmc_request *mrq = host->mrq;
+        struct mmc_command *cmd;
+        int trans;
+
+        if (!host->mrq)
+                return;
+
+        cmd = mrq->cmd;
+        cmd->error = MMC_ERR_NONE;
+
+        if ((cmd->flags & MMC_RSP_MASK) == MMC_RSP_SHORT) {
+
+                /* Techincally, we should be getting all 48 bits of the response
+                 * (SD_RESP1 + SD_RESP2), but because our response omits the CRC,
+                 * our data ends up being shifted 8 bits to the right.  In this case,
+                 * that means that the OSR data starts at bit 31, so we can just
+                 * read RESP0 and return that
+                 */
+
+                cmd->resp[0] = au_readl(host->iobase + SD_RESP0);
+        }
+        else if ((cmd->flags & MMC_RSP_MASK) == MMC_RSP_LONG) {
+                u32 r[4];
+                int i;
+
+                r[0] = au_readl(host->iobase + SD_RESP3);
+                r[1] = au_readl(host->iobase + SD_RESP2);
+                r[2] = au_readl(host->iobase + SD_RESP1);
+                r[3] = au_readl(host->iobase + SD_RESP0);
+
+                /* The CRC is omitted from the response, so really we only got
+                 * 120 bytes, but the engine expects 128 bits, so we have to shift
+                 * things up
+                 */
+
+                for(i = 0; i < 4; i++) {
+                        cmd->resp[i] = (r[i] & 0x00FFFFFF) << 8;
+                        if (i != 3) cmd->resp[i] |= (r[i + 1] & 0xFF000000) >> 24;
+                }
+        }
+
+        /* Figure out errors */
+
+        if (status & (SD_STATUS_SC | SD_STATUS_WC | SD_STATUS_RC))
+                cmd->error = MMC_ERR_BADCRC;
+
+        trans = host->flags & (HOST_F_XMIT | HOST_F_RECV);
+
+        if (!trans || cmd->error != MMC_ERR_NONE) {
+
+                IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA|SD_CONFIG_RF);
+                tasklet_schedule(&host->finish_task);
+                return;
+        }
+
+        host->status = HOST_S_DATA;
+
+        if (host->flags & HOST_F_DMA) {
+                u32 channel = DMA_CHANNEL(host);
+
+                /* Start the DMA as soon as the buffer gets something in it */
+
+                if (host->flags & HOST_F_RECV) {
+                        u32 mask = SD_STATUS_DB | SD_STATUS_NE;
+
+                        while((status & mask) != mask)
+                                status = au_readl(HOST_STATUS(host));
+                }
+
+                au1xxx_dbdma_start(channel);
+        }
+}
+
+static void au1xmmc_set_clock(struct au1xmmc_host *host, int rate)
+{
+
+        unsigned int pbus = get_au1x00_speed();
+        unsigned int divisor;
+        u32 config;
+
+        /* From databook:
+           divisor = ((((cpuclock / sbus_divisor) / 2) / mmcclock) / 2) - 1
+        */
+
+        pbus /= ((au_readl(SYS_POWERCTRL) & 0x3) + 2);
+        pbus /= 2;
+
+        divisor = ((pbus / rate) / 2) - 1;
+
+        config = au_readl(HOST_CONFIG(host));
+
+        config &= ~(SD_CONFIG_DIV);
+        config |= (divisor & SD_CONFIG_DIV) | SD_CONFIG_DE;
+
+        au_writel(config, HOST_CONFIG(host));
+        au_sync();
+}
+
+static int
+au1xmmc_prepare_data(struct au1xmmc_host *host, struct mmc_data *data)
+{
+
+        int datalen = data->blocks * (1 << data->blksz_bits);
+
+        if (dma != 0)
+                host->flags |= HOST_F_DMA;
+
+        if (data->flags & MMC_DATA_READ)
+                host->flags |= HOST_F_RECV;
+        else
+                host->flags |= HOST_F_XMIT;
+
+        if (host->mrq->stop)
+                host->flags |= HOST_F_STOP;
+
+        host->dma.dir = DMA_BIDIRECTIONAL;
+
+        host->dma.len = dma_map_sg(mmc_dev(host->mmc), data->sg,
+                                   data->sg_len, host->dma.dir);
+
+        if (host->dma.len == 0)
+                return MMC_ERR_TIMEOUT;
+
+        au_writel((1 << data->blksz_bits) - 1, HOST_BLKSIZE(host));
+
+        if (host->flags & HOST_F_DMA) {
+                int i;
+                u32 channel = DMA_CHANNEL(host);
+
+                au1xxx_dbdma_stop(channel);
+
+                for(i = 0; i < host->dma.len; i++) {
+                        u32 ret = 0, flags = DDMA_FLAGS_NOIE;
+                        struct scatterlist *sg = &data->sg[i];
+                        int sg_len = sg->length;
+
+                        int len = (datalen > sg_len) ? sg_len : datalen;
+
+                        if (i == host->dma.len - 1)
+                                flags = DDMA_FLAGS_IE;
+
+                        if (host->flags & HOST_F_XMIT){
+                                ret = au1xxx_dbdma_put_source_flags(channel,
+                                        (void *) (page_address(sg->page) +
+                                                  sg->offset),
+                                        len, flags);
+                        }
+                        else {
+                                ret = au1xxx_dbdma_put_dest_flags(channel,
+                                        (void *) (page_address(sg->page) +
+                                                  sg->offset),
+                                        len, flags);
+                        }
+
+                        if (!ret)
+                                goto dataerr;
+
+                        datalen -= len;
+                }
+        }
+        else {
+                host->pio.index = 0;
+                host->pio.offset = 0;
+                host->pio.len = datalen;
+
+                if (host->flags & HOST_F_XMIT)
+                        IRQ_ON(host, SD_CONFIG_TH);
+                else
+                        IRQ_ON(host, SD_CONFIG_NE);
+                        //IRQ_ON(host, SD_CONFIG_RA|SD_CONFIG_RF);
+        }
+
+        return MMC_ERR_NONE;
+
+ dataerr:
+        dma_unmap_sg(mmc_dev(host->mmc),data->sg,data->sg_len,host->dma.dir);
+        return MMC_ERR_TIMEOUT;
+}
+
+/* static void au1xmmc_request
+   This actually starts a command or data transaction
+*/
+
+static void au1xmmc_request(struct mmc_host* mmc, struct mmc_request* mrq)
+{
+
+        struct au1xmmc_host *host = mmc_priv(mmc);
+        int ret = MMC_ERR_NONE;
+
+        WARN_ON(irqs_disabled());
+        WARN_ON(host->status != HOST_S_IDLE);
+
+        host->mrq = mrq;
+        host->status = HOST_S_CMD;
+
+        bcsr->disk_leds &= ~(1 << 8);
+
+        if (mrq->data) {
+                FLUSH_FIFO(host);
+                ret = au1xmmc_prepare_data(host, mrq->data);
+        }
+
+        if (ret == MMC_ERR_NONE)
+                ret = au1xmmc_send_command(host, 0, mrq->cmd);
+
+        if (ret != MMC_ERR_NONE) {
+                mrq->cmd->error = ret;
+                au1xmmc_finish_request(host);
+        }
+}
+
+static void au1xmmc_reset_controller(struct au1xmmc_host *host)
+{
+
+        /* Apply the clock */
+        au_writel(SD_ENABLE_CE, HOST_ENABLE(host));
+        au_sync_delay(1);
+
+        au_writel(SD_ENABLE_R | SD_ENABLE_CE, HOST_ENABLE(host));
+        au_sync_delay(5);
+
+        au_writel(~0, HOST_STATUS(host));
+        au_sync();
+
+        au_writel(0, HOST_BLKSIZE(host));
+        au_writel(0x001fffff, HOST_TIMEOUT(host));
+        au_sync();
+
+        au_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
+        au_sync();
+
+        au_writel(SD_CONFIG2_EN | SD_CONFIG2_FF, HOST_CONFIG2(host));
+        au_sync_delay(1);
+
+        au_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
+        au_sync();
+
+        /* Configure interrupts */
+        au_writel(AU1XMMC_INTERRUPTS, HOST_CONFIG(host));
+        au_sync();
+}
+
+
+static void au1xmmc_set_ios(struct mmc_host* mmc, struct mmc_ios* ios)
+{
+        struct au1xmmc_host *host = mmc_priv(mmc);
+
+        DEBUG("set_ios (power=%u, clock=%uHz, vdd=%u, mode=%u)\n",
+              host->id, ios->power_mode, ios->clock, ios->vdd,
+              ios->bus_mode);
+
+        if (ios->power_mode == MMC_POWER_OFF)
+                au1xmmc_set_power(host, 0);
+        else if (ios->power_mode == MMC_POWER_ON) {
+                au1xmmc_set_power(host, 1);
+        }
+
+        if (ios->clock && ios->clock != host->clock) {
+                au1xmmc_set_clock(host, ios->clock);
+                host->clock = ios->clock;
+        }
+}
+
+static void au1xmmc_dma_callback(int irq, void *dev_id, struct pt_regs *regs)
+{
+        struct au1xmmc_host *host = (struct au1xmmc_host *) dev_id;
+        u32 status;
+
+        /* Avoid spurious interrupts */
+
+        if (!host->mrq)
+                return;
+
+        if (host->flags & HOST_F_STOP)
+                SEND_STOP(host);
+
+        tasklet_schedule(&host->data_task);
+}
+
+#define STATUS_TIMEOUT (SD_STATUS_RAT | SD_STATUS_DT)
+#define STATUS_DATA_IN  (SD_STATUS_NE)
+#define STATUS_DATA_OUT (SD_STATUS_TH)
+
+static irqreturn_t au1xmmc_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+
+        u32 status;
+        int i, ret = 0;
+
+        disable_irq(AU1100_SD_IRQ);
+
+        for(i = 0; i < AU1XMMC_CONTROLLER_COUNT; i++) {
+                struct au1xmmc_host * host = au1xmmc_hosts[i];
+                u32 handled = 1;
+
+                status = au_readl(HOST_STATUS(host));
+
+                if (host->mrq && (status & STATUS_TIMEOUT)) {
+                        if (status & SD_STATUS_RAT)
+                                host->mrq->cmd->error = MMC_ERR_TIMEOUT;
+
+                        else if (status & SD_STATUS_DT)
+                                host->mrq->data->error = MMC_ERR_TIMEOUT;
+
+                        /* In PIO mode, interrupts might still be enabled */
+                        IRQ_OFF(host, SD_CONFIG_NE | SD_CONFIG_TH);
+
+                        //IRQ_OFF(host, SD_CONFIG_TH|SD_CONFIG_RA|SD_CONFIG_RF);
+                        tasklet_schedule(&host->finish_task);
+                }
+#if 0
+                else if (status & SD_STATUS_DD) {
+
+                        /* Sometimes we get a DD before a NE in PIO mode */
+
+                        if (!(host->flags & HOST_F_DMA) &&
+                                        (status & SD_STATUS_NE))
+                                au1xmmc_receive_pio(host);
+                        else {
+                                au1xmmc_data_complete(host, status);
+                                //tasklet_schedule(&host->data_task);
+                        }
+                }
+#endif
+                else if (status & (SD_STATUS_CR)) {
+                        if (host->status == HOST_S_CMD)
+                                au1xmmc_cmd_complete(host,status);
+                }
+                else if (!(host->flags & HOST_F_DMA)) {
+                        if ((host->flags & HOST_F_XMIT) &&
+                            (status & STATUS_DATA_OUT))
+                                au1xmmc_send_pio(host);
+                        else if ((host->flags & HOST_F_RECV) &&
+                            (status & STATUS_DATA_IN))
+                                au1xmmc_receive_pio(host);
+                }
+                else if (status & 0x203FBC70) {
+                        DEBUG("Unhandled status %8.8x\n", host->id, status);
+                        handled = 0;
+                }
+
+                au_writel(status, HOST_STATUS(host));
+                au_sync();
+
+                ret |= handled;
+        }
+
+        enable_irq(AU1100_SD_IRQ);
+        return ret;
+}
+
+static void au1xmmc_poll_event(unsigned long arg)
+{
+        struct au1xmmc_host *host = (struct au1xmmc_host *) arg;
+
+        int card = au1xmmc_card_inserted(host);
+        int controller = (host->flags & HOST_F_ACTIVE) ? 1 : 0;
+
+        if (card != controller) {
+                host->flags &= ~HOST_F_ACTIVE;
+                if (card) host->flags |= HOST_F_ACTIVE;
+                mmc_detect_change(host->mmc, 0);
+        }
+
+        if (host->mrq != NULL) {
+                u32 status = au_readl(HOST_STATUS(host));
+                DEBUG("PENDING - %8.8x\n", host->id, status);
+        }
+
+        mod_timer(&host->timer, jiffies + AU1XMMC_DETECT_TIMEOUT);
+}
+
+static dbdev_tab_t au1xmmc_mem_dbdev =
+{
+        DSCR_CMD0_ALWAYS, DEV_FLAGS_ANYUSE, 0, 8, 0x00000000, 0, 0
+};
+
+static void au1xmmc_init_dma(struct au1xmmc_host *host)
+{
+
+        u32 rxchan, txchan;
+
+        int txid = au1xmmc_card_table[host->id].tx_devid;
+        int rxid = au1xmmc_card_table[host->id].rx_devid;
+
+        /* DSCR_CMD0_ALWAYS has a stride of 32 bits, we need a stride
+           of 8 bits.  And since devices are shared, we need to create
+           our own to avoid freaking out other devices
+        */
+
+        int memid = au1xxx_ddma_add_device(&au1xmmc_mem_dbdev);
+
+        txchan = au1xxx_dbdma_chan_alloc(memid, txid,
+                                         au1xmmc_dma_callback, (void *) host);
+
+        rxchan = au1xxx_dbdma_chan_alloc(rxid, memid,
+                                         au1xmmc_dma_callback, (void *) host);
+
+        au1xxx_dbdma_set_devwidth(txchan, 8);
+        au1xxx_dbdma_set_devwidth(rxchan, 8);
+
+        au1xxx_dbdma_ring_alloc(txchan, AU1XMMC_DESCRIPTOR_COUNT);
+        au1xxx_dbdma_ring_alloc(rxchan, AU1XMMC_DESCRIPTOR_COUNT);
+
+        host->tx_chan = txchan;
+        host->rx_chan = rxchan;
+}
+
+struct mmc_host_ops au1xmmc_ops = {
+        .request        = au1xmmc_request,
+        .set_ios        = au1xmmc_set_ios,
+};
+
+static int au1xmmc_probe(struct device *dev)
+{
+
+        int i, ret = 0;
+
+        /* THe interrupt is shared among all controllers */
+        ret = request_irq(AU1100_SD_IRQ, au1xmmc_irq, SA_INTERRUPT, "MMC", 0);
+
+        if (ret) {
+                printk(DRIVER_NAME "ERROR: Couldn't get int %d: %d\n",
+                                AU1100_SD_IRQ, ret);
+                return -ENXIO;
+        }
+
+        disable_irq(AU1100_SD_IRQ);
+
+        for(i = 0; i < AU1XMMC_CONTROLLER_COUNT; i++) {
+                struct mmc_host *mmc = mmc_alloc_host(sizeof(struct au1xmmc_host), dev);
+                struct au1xmmc_host *host = 0;
+
+                if (!mmc) {
+                        printk(DRIVER_NAME "ERROR: no mem for host %d\n", i);
+                        au1xmmc_hosts[i] = 0;
+                        continue;
+                }
+
+                mmc->ops = &au1xmmc_ops;
+
+                mmc->f_min =   450000;
+                mmc->f_max = 24000000;
+
+                mmc->max_seg_size = AU1XMMC_DESCRIPTOR_SIZE;
+                mmc->max_phys_segs = AU1XMMC_DESCRIPTOR_COUNT;
+
+                mmc->ocr_avail = AU1XMMC_OCR;
+
+                host = mmc_priv(mmc);
+                host->mmc = mmc;
+
+                host->id = i;
+                host->iobase = au1xmmc_card_table[host->id].iobase;
+                host->clock = 0;
+                host->power_mode = MMC_POWER_OFF;
+
+                host->flags = au1xmmc_card_inserted(host) ? HOST_F_ACTIVE : 0;
+                host->status = HOST_S_IDLE;
+
+                init_timer(&host->timer);
+
+                host->timer.function = au1xmmc_poll_event;
+                host->timer.data = (unsigned long) host;
+                host->timer.expires = jiffies + AU1XMMC_DETECT_TIMEOUT;
+
+                tasklet_init(&host->data_task, au1xmmc_tasklet_data,
+                                (unsigned long) host);
+
+                tasklet_init(&host->finish_task, au1xmmc_tasklet_finish,
+                                (unsigned long) host);
+
+                spin_lock_init(&host->lock);
+
+                if (dma != 0)
+                        au1xmmc_init_dma(host);
+
+                au1xmmc_reset_controller(host);
+
+                mmc_add_host(mmc);
+                au1xmmc_hosts[i] = host;
+
+                add_timer(&host->timer);
+
+                printk(KERN_INFO DRIVER_NAME ": MMC Controller %d set up at %8.8X (mode=%s)\n",
+                       host->id, host->iobase, dma ? "dma" : "pio");
+        }
+
+        enable_irq(AU1100_SD_IRQ);
+
+        return 0;
+}
+
+static int au1xmmc_remove(struct device *dev)
+{
+
+        int i;
+
+        disable_irq(AU1100_SD_IRQ);
+
+        for(i = 0; i < AU1XMMC_CONTROLLER_COUNT; i++) {
+                struct au1xmmc_host *host = au1xmmc_hosts[i];
+                if (!host) continue;
+
+                tasklet_kill(&host->data_task);
+                tasklet_kill(&host->finish_task);
+
+                del_timer_sync(&host->timer);
+                au1xmmc_set_power(host, 0);
+
+                mmc_remove_host(host->mmc);
+
+                au1xxx_dbdma_chan_free(host->tx_chan);
+                au1xxx_dbdma_chan_free(host->rx_chan);
+
+                au_writel(0x0, HOST_ENABLE(host));
+                au_sync();
+        }
+
+        free_irq(AU1100_SD_IRQ, 0);
+        return 0;
+}
+
+static struct device_driver au1xmmc_driver = {
+        .name          = DRIVER_NAME,
+        .bus           = &platform_bus_type,
+        .probe         = au1xmmc_probe,
+        .remove        = au1xmmc_remove,
+        .suspend       = NULL,
+        .resume        = NULL
+};
+
+static int __init au1xmmc_init(void)
+{
+        return driver_register(&au1xmmc_driver);
+}
+
+static void __exit au1xmmc_exit(void)
+{
+        driver_unregister(&au1xmmc_driver);
+}
+
+module_init(au1xmmc_init);
+module_exit(au1xmmc_exit);
+
+#ifdef MODULE
+MODULE_AUTHOR("Advanced Micro Devices, Inc");
+MODULE_DESCRIPTION("MMC/SD driver for the Alchemy Au1XXX");
+MODULE_LICENSE("GPL");
+#endif
+
diff --git a/drivers/mmc/au1xmmc.h b/drivers/mmc/au1xmmc.h
new file mode 100644
index 000000000000..341cbdf0baca
--- /dev/null
+++ b/drivers/mmc/au1xmmc.h
@@ -0,0 +1,96 @@
+#ifndef _AU1XMMC_H_
+#define _AU1XMMC_H_
+
+/* Hardware definitions */
+
+#define AU1XMMC_DESCRIPTOR_COUNT 1
+#define AU1XMMC_DESCRIPTOR_SIZE  2048
+
+#define AU1XMMC_OCR ( MMC_VDD_27_28 | MMC_VDD_28_29 | MMC_VDD_29_30  | \
+                      MMC_VDD_30_31 | MMC_VDD_31_32 | MMC_VDD_32_33  | \
+                      MMC_VDD_33_34 | MMC_VDD_34_35 | MMC_VDD_35_36)
+
+/* Easy access macros */
+
+#define HOST_STATUS(h)  ((h)->iobase + SD_STATUS)
+#define HOST_CONFIG(h)  ((h)->iobase + SD_CONFIG)
+#define HOST_ENABLE(h)  ((h)->iobase + SD_ENABLE)
+#define HOST_TXPORT(h)  ((h)->iobase + SD_TXPORT)
+#define HOST_RXPORT(h)  ((h)->iobase + SD_RXPORT)
+#define HOST_CMDARG(h)  ((h)->iobase + SD_CMDARG)
+#define HOST_BLKSIZE(h) ((h)->iobase + SD_BLKSIZE)
+#define HOST_CMD(h)     ((h)->iobase + SD_CMD)
+#define HOST_CONFIG2(h) ((h)->iobase + SD_CONFIG2)
+#define HOST_TIMEOUT(h) ((h)->iobase + SD_TIMEOUT)
+#define HOST_DEBUG(h)   ((h)->iobase + SD_DEBUG)
+
+#define DMA_CHANNEL(h) \
+        ( ((h)->flags & HOST_F_XMIT) ? (h)->tx_chan : (h)->rx_chan)
+
+/* This gives us a hard value for the stop command that we can write directly
+ * to the command register
+ */
+
+#define STOP_CMD (SD_CMD_RT_1B|SD_CMD_CT_7|(0xC << SD_CMD_CI_SHIFT)|SD_CMD_GO)
+
+/* This is the set of interrupts that we configure by default */
+
+#if 0
+#define AU1XMMC_INTERRUPTS (SD_CONFIG_SC | SD_CONFIG_DT | SD_CONFIG_DD | \
+                SD_CONFIG_RAT | SD_CONFIG_CR | SD_CONFIG_I)
+#endif
+
+#define AU1XMMC_INTERRUPTS (SD_CONFIG_SC | SD_CONFIG_DT | \
+                SD_CONFIG_RAT | SD_CONFIG_CR | SD_CONFIG_I)
+/* The poll event (looking for insert/remove events runs twice a second */
+#define AU1XMMC_DETECT_TIMEOUT (HZ/2)
+
+struct au1xmmc_host {
+  struct mmc_host *mmc;
+  struct mmc_request *mrq;
+
+  u32 id;
+
+  u32 flags;
+  u32 iobase;
+  u32 clock;
+  u32 bus_width;
+  u32 power_mode;
+
+  int status;
+
+   struct {
+           int len;
+           int dir;
+  } dma;
+
+   struct {
+           int index;
+           int offset;
+           int len;
+  } pio;
+
+  u32 tx_chan;
+  u32 rx_chan;
+
+  struct timer_list timer;
+  struct tasklet_struct finish_task;
+  struct tasklet_struct data_task;
+
+  spinlock_t lock;
+};
+
+/* Status flags used by the host structure */
+
+#define HOST_F_XMIT   0x0001
+#define HOST_F_RECV   0x0002
+#define HOST_F_DMA    0x0010
+#define HOST_F_ACTIVE 0x0100
+#define HOST_F_STOP   0x1000
+
+#define HOST_S_IDLE   0x0001
+#define HOST_S_CMD    0x0002
+#define HOST_S_DATA   0x0003
+#define HOST_S_STOP   0x0004
+
+#endif