1 files changed, 1186 insertions, 0 deletions

diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
new file mode 100644
index 000000000000..d2407558773f
--- /dev/null
+++ b/drivers/spi/spi-fsl-spi.c
@@ -0,0 +1,1186 @@
+/*
+ * Freescale SPI controller driver.
+ *
+ * Maintainer: Kumar Gala
+ *
+ * Copyright (C) 2006 Polycom, Inc.
+ * Copyright 2010 Freescale Semiconductor, Inc.
+ *
+ * CPM SPI and QE buffer descriptors mode support:
+ * Copyright (c) 2009  MontaVista Software, Inc.
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/platform_device.h>
+#include <linux/fsl_devices.h>
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+
+#include <sysdev/fsl_soc.h>
+#include <asm/cpm.h>
+#include <asm/qe.h>
+
+#include "spi-fsl-lib.h"
+
+/* CPM1 and CPM2 are mutually exclusive. */
+#ifdef CONFIG_CPM1
+#include <asm/cpm1.h>
+#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0)
+#else
+#include <asm/cpm2.h>
+#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0)
+#endif
+
+/* SPI Controller registers */
+struct fsl_spi_reg {
+        u8 res1[0x20];
+        __be32 mode;
+        __be32 event;
+        __be32 mask;
+        __be32 command;
+        __be32 transmit;
+        __be32 receive;
+};
+
+/* SPI Controller mode register definitions */
+#define SPMODE_LOOP             (1 << 30)
+#define SPMODE_CI_INACTIVEHIGH  (1 << 29)
+#define SPMODE_CP_BEGIN_EDGECLK (1 << 28)
+#define SPMODE_DIV16            (1 << 27)
+#define SPMODE_REV              (1 << 26)
+#define SPMODE_MS               (1 << 25)
+#define SPMODE_ENABLE           (1 << 24)
+#define SPMODE_LEN(x)           ((x) << 20)
+#define SPMODE_PM(x)            ((x) << 16)
+#define SPMODE_OP               (1 << 14)
+#define SPMODE_CG(x)            ((x) << 7)
+
+/*
+ * Default for SPI Mode:
+ *      SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk
+ */
+#define SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \
+                         SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf))
+
+/* SPIE register values */
+#define SPIE_NE         0x00000200      /* Not empty */
+#define SPIE_NF         0x00000100      /* Not full */
+
+/* SPIM register values */
+#define SPIM_NE         0x00000200      /* Not empty */
+#define SPIM_NF         0x00000100      /* Not full */
+
+#define SPIE_TXB        0x00000200      /* Last char is written to tx fifo */
+#define SPIE_RXB        0x00000100      /* Last char is written to rx buf */
+
+/* SPCOM register values */
+#define SPCOM_STR       (1 << 23)       /* Start transmit */
+
+#define SPI_PRAM_SIZE   0x100
+#define SPI_MRBLR       ((unsigned int)PAGE_SIZE)
+
+static void *fsl_dummy_rx;
+static DEFINE_MUTEX(fsl_dummy_rx_lock);
+static int fsl_dummy_rx_refcnt;
+
+static void fsl_spi_change_mode(struct spi_device *spi)
+{
+        struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+        struct spi_mpc8xxx_cs *cs = spi->controller_state;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+        __be32 __iomem *mode = &reg_base->mode;
+        unsigned long flags;
+
+        if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
+                return;
+
+        /* Turn off IRQs locally to minimize time that SPI is disabled. */
+        local_irq_save(flags);
+
+        /* Turn off SPI unit prior changing mode */
+        mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
+
+        /* When in CPM mode, we need to reinit tx and rx. */
+        if (mspi->flags & SPI_CPM_MODE) {
+                if (mspi->flags & SPI_QE) {
+                        qe_issue_cmd(QE_INIT_TX_RX, mspi->subblock,
+                                     QE_CR_PROTOCOL_UNSPECIFIED, 0);
+                } else {
+                        cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX);
+                        if (mspi->flags & SPI_CPM1) {
+                                out_be16(&mspi->pram->rbptr,
+                                         in_be16(&mspi->pram->rbase));
+                                out_be16(&mspi->pram->tbptr,
+                                         in_be16(&mspi->pram->tbase));
+                        }
+                }
+        }
+        mpc8xxx_spi_write_reg(mode, cs->hw_mode);
+        local_irq_restore(flags);
+}
+
+static void fsl_spi_chipselect(struct spi_device *spi, int value)
+{
+        struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+        struct fsl_spi_platform_data *pdata = spi->dev.parent->platform_data;
+        bool pol = spi->mode & SPI_CS_HIGH;
+        struct spi_mpc8xxx_cs   *cs = spi->controller_state;
+
+        if (value == BITBANG_CS_INACTIVE) {
+                if (pdata->cs_control)
+                        pdata->cs_control(spi, !pol);
+        }
+
+        if (value == BITBANG_CS_ACTIVE) {
+                mpc8xxx_spi->rx_shift = cs->rx_shift;
+                mpc8xxx_spi->tx_shift = cs->tx_shift;
+                mpc8xxx_spi->get_rx = cs->get_rx;
+                mpc8xxx_spi->get_tx = cs->get_tx;
+
+                fsl_spi_change_mode(spi);
+
+                if (pdata->cs_control)
+                        pdata->cs_control(spi, pol);
+        }
+}
+
+static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
+                                struct spi_device *spi,
+                                struct mpc8xxx_spi *mpc8xxx_spi,
+                                int bits_per_word)
+{
+        cs->rx_shift = 0;
+        cs->tx_shift = 0;
+        if (bits_per_word <= 8) {
+                cs->get_rx = mpc8xxx_spi_rx_buf_u8;
+                cs->get_tx = mpc8xxx_spi_tx_buf_u8;
+                if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+                        cs->rx_shift = 16;
+                        cs->tx_shift = 24;
+                }
+        } else if (bits_per_word <= 16) {
+                cs->get_rx = mpc8xxx_spi_rx_buf_u16;
+                cs->get_tx = mpc8xxx_spi_tx_buf_u16;
+                if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+                        cs->rx_shift = 16;
+                        cs->tx_shift = 16;
+                }
+        } else if (bits_per_word <= 32) {
+                cs->get_rx = mpc8xxx_spi_rx_buf_u32;
+                cs->get_tx = mpc8xxx_spi_tx_buf_u32;
+        } else
+                return -EINVAL;
+
+        if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE &&
+            spi->mode & SPI_LSB_FIRST) {
+                cs->tx_shift = 0;
+                if (bits_per_word <= 8)
+                        cs->rx_shift = 8;
+                else
+                        cs->rx_shift = 0;
+        }
+        mpc8xxx_spi->rx_shift = cs->rx_shift;
+        mpc8xxx_spi->tx_shift = cs->tx_shift;
+        mpc8xxx_spi->get_rx = cs->get_rx;
+        mpc8xxx_spi->get_tx = cs->get_tx;
+
+        return bits_per_word;
+}
+
+static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
+                                struct spi_device *spi,
+                                int bits_per_word)
+{
+        /* QE uses Little Endian for words > 8
+         * so transform all words > 8 into 8 bits
+         * Unfortnatly that doesn't work for LSB so
+         * reject these for now */
+        /* Note: 32 bits word, LSB works iff
+         * tfcr/rfcr is set to CPMFCR_GBL */
+        if (spi->mode & SPI_LSB_FIRST &&
+            bits_per_word > 8)
+                return -EINVAL;
+        if (bits_per_word > 8)
+                return 8; /* pretend its 8 bits */
+        return bits_per_word;
+}
+
+static int fsl_spi_setup_transfer(struct spi_device *spi,
+                                        struct spi_transfer *t)
+{
+        struct mpc8xxx_spi *mpc8xxx_spi;
+        int bits_per_word = 0;
+        u8 pm;
+        u32 hz = 0;
+        struct spi_mpc8xxx_cs   *cs = spi->controller_state;
+
+        mpc8xxx_spi = spi_master_get_devdata(spi->master);
+
+        if (t) {
+                bits_per_word = t->bits_per_word;
+                hz = t->speed_hz;
+        }
+
+        /* spi_transfer level calls that work per-word */
+        if (!bits_per_word)
+                bits_per_word = spi->bits_per_word;
+
+        /* Make sure its a bit width we support [4..16, 32] */
+        if ((bits_per_word < 4)
+            || ((bits_per_word > 16) && (bits_per_word != 32)))
+                return -EINVAL;
+
+        if (!hz)
+                hz = spi->max_speed_hz;
+
+        if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
+                bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
+                                                           mpc8xxx_spi,
+                                                           bits_per_word);
+        else if (mpc8xxx_spi->flags & SPI_QE)
+                bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
+                                                          bits_per_word);
+
+        if (bits_per_word < 0)
+                return bits_per_word;
+
+        if (bits_per_word == 32)
+                bits_per_word = 0;
+        else
+                bits_per_word = bits_per_word - 1;
+
+        /* mask out bits we are going to set */
+        cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
+                                  | SPMODE_PM(0xF));
+
+        cs->hw_mode |= SPMODE_LEN(bits_per_word);
+
+        if ((mpc8xxx_spi->spibrg / hz) > 64) {
+                cs->hw_mode |= SPMODE_DIV16;
+                pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
+
+                WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
+                          "Will use %d Hz instead.\n", dev_name(&spi->dev),
+                          hz, mpc8xxx_spi->spibrg / 1024);
+                if (pm > 16)
+                        pm = 16;
+        } else {
+                pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
+        }
+        if (pm)
+                pm--;
+
+        cs->hw_mode |= SPMODE_PM(pm);
+
+        fsl_spi_change_mode(spi);
+        return 0;
+}
+
+static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi)
+{
+        struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd;
+        struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd;
+        unsigned int xfer_len = min(mspi->count, SPI_MRBLR);
+        unsigned int xfer_ofs;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        xfer_ofs = mspi->xfer_in_progress->len - mspi->count;
+
+        if (mspi->rx_dma == mspi->dma_dummy_rx)
+                out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma);
+        else
+                out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma + xfer_ofs);
+        out_be16(&rx_bd->cbd_datlen, 0);
+        out_be16(&rx_bd->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP);
+
+        if (mspi->tx_dma == mspi->dma_dummy_tx)
+                out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma);
+        else
+                out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma + xfer_ofs);
+        out_be16(&tx_bd->cbd_datlen, xfer_len);
+        out_be16(&tx_bd->cbd_sc, BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP |
+                                 BD_SC_LAST);
+
+        /* start transfer */
+        mpc8xxx_spi_write_reg(&reg_base->command, SPCOM_STR);
+}
+
+static int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi,
+                                struct spi_transfer *t, bool is_dma_mapped)
+{
+        struct device *dev = mspi->dev;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        if (is_dma_mapped) {
+                mspi->map_tx_dma = 0;
+                mspi->map_rx_dma = 0;
+        } else {
+                mspi->map_tx_dma = 1;
+                mspi->map_rx_dma = 1;
+        }
+
+        if (!t->tx_buf) {
+                mspi->tx_dma = mspi->dma_dummy_tx;
+                mspi->map_tx_dma = 0;
+        }
+
+        if (!t->rx_buf) {
+                mspi->rx_dma = mspi->dma_dummy_rx;
+                mspi->map_rx_dma = 0;
+        }
+
+        if (mspi->map_tx_dma) {
+                void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */
+
+                mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len,
+                                              DMA_TO_DEVICE);
+                if (dma_mapping_error(dev, mspi->tx_dma)) {
+                        dev_err(dev, "unable to map tx dma\n");
+                        return -ENOMEM;
+                }
+        } else if (t->tx_buf) {
+                mspi->tx_dma = t->tx_dma;
+        }
+
+        if (mspi->map_rx_dma) {
+                mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len,
+                                              DMA_FROM_DEVICE);
+                if (dma_mapping_error(dev, mspi->rx_dma)) {
+                        dev_err(dev, "unable to map rx dma\n");
+                        goto err_rx_dma;
+                }
+        } else if (t->rx_buf) {
+                mspi->rx_dma = t->rx_dma;
+        }
+
+        /* enable rx ints */
+        mpc8xxx_spi_write_reg(&reg_base->mask, SPIE_RXB);
+
+        mspi->xfer_in_progress = t;
+        mspi->count = t->len;
+
+        /* start CPM transfers */
+        fsl_spi_cpm_bufs_start(mspi);
+
+        return 0;
+
+err_rx_dma:
+        if (mspi->map_tx_dma)
+                dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
+        return -ENOMEM;
+}
+
+static void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi)
+{
+        struct device *dev = mspi->dev;
+        struct spi_transfer *t = mspi->xfer_in_progress;
+
+        if (mspi->map_tx_dma)
+                dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
+        if (mspi->map_rx_dma)
+                dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE);
+        mspi->xfer_in_progress = NULL;
+}
+
+static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
+                                struct spi_transfer *t, unsigned int len)
+{
+        u32 word;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        mspi->count = len;
+
+        /* enable rx ints */
+        mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
+
+        /* transmit word */
+        word = mspi->get_tx(mspi);
+        mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+
+        return 0;
+}
+
+static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
+                            bool is_dma_mapped)
+{
+        struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+        struct fsl_spi_reg *reg_base;
+        unsigned int len = t->len;
+        u8 bits_per_word;
+        int ret;
+
+        reg_base = mpc8xxx_spi->reg_base;
+        bits_per_word = spi->bits_per_word;
+        if (t->bits_per_word)
+                bits_per_word = t->bits_per_word;
+
+        if (bits_per_word > 8) {
+                /* invalid length? */
+                if (len & 1)
+                        return -EINVAL;
+                len /= 2;
+        }
+        if (bits_per_word > 16) {
+                /* invalid length? */
+                if (len & 1)
+                        return -EINVAL;
+                len /= 2;
+        }
+
+        mpc8xxx_spi->tx = t->tx_buf;
+        mpc8xxx_spi->rx = t->rx_buf;
+
+        INIT_COMPLETION(mpc8xxx_spi->done);
+
+        if (mpc8xxx_spi->flags & SPI_CPM_MODE)
+                ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
+        else
+                ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
+        if (ret)
+                return ret;
+
+        wait_for_completion(&mpc8xxx_spi->done);
+
+        /* disable rx ints */
+        mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+
+        if (mpc8xxx_spi->flags & SPI_CPM_MODE)
+                fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
+
+        return mpc8xxx_spi->count;
+}
+
+static void fsl_spi_do_one_msg(struct spi_message *m)
+{
+        struct spi_device *spi = m->spi;
+        struct spi_transfer *t;
+        unsigned int cs_change;
+        const int nsecs = 50;
+        int status;
+
+        cs_change = 1;
+        status = 0;
+        list_for_each_entry(t, &m->transfers, transfer_list) {
+                if (t->bits_per_word || t->speed_hz) {
+                        /* Don't allow changes if CS is active */
+                        status = -EINVAL;
+
+                        if (cs_change)
+                                status = fsl_spi_setup_transfer(spi, t);
+                        if (status < 0)
+                                break;
+                }
+
+                if (cs_change) {
+                        fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+                        ndelay(nsecs);
+                }
+                cs_change = t->cs_change;
+                if (t->len)
+                        status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
+                if (status) {
+                        status = -EMSGSIZE;
+                        break;
+                }
+                m->actual_length += t->len;
+
+                if (t->delay_usecs)
+                        udelay(t->delay_usecs);
+
+                if (cs_change) {
+                        ndelay(nsecs);
+                        fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+                        ndelay(nsecs);
+                }
+        }
+
+        m->status = status;
+        m->complete(m->context);
+
+        if (status || !cs_change) {
+                ndelay(nsecs);
+                fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+        }
+
+        fsl_spi_setup_transfer(spi, NULL);
+}
+
+static int fsl_spi_setup(struct spi_device *spi)
+{
+        struct mpc8xxx_spi *mpc8xxx_spi;
+        struct fsl_spi_reg *reg_base;
+        int retval;
+        u32 hw_mode;
+        struct spi_mpc8xxx_cs   *cs = spi->controller_state;
+
+        if (!spi->max_speed_hz)
+                return -EINVAL;
+
+        if (!cs) {
+                cs = kzalloc(sizeof *cs, GFP_KERNEL);
+                if (!cs)
+                        return -ENOMEM;
+                spi->controller_state = cs;
+        }
+        mpc8xxx_spi = spi_master_get_devdata(spi->master);
+
+        reg_base = mpc8xxx_spi->reg_base;
+
+        hw_mode = cs->hw_mode; /* Save original settings */
+        cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
+        /* mask out bits we are going to set */
+        cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
+                         | SPMODE_REV | SPMODE_LOOP);
+
+        if (spi->mode & SPI_CPHA)
+                cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
+        if (spi->mode & SPI_CPOL)
+                cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
+        if (!(spi->mode & SPI_LSB_FIRST))
+                cs->hw_mode |= SPMODE_REV;
+        if (spi->mode & SPI_LOOP)
+                cs->hw_mode |= SPMODE_LOOP;
+
+        retval = fsl_spi_setup_transfer(spi, NULL);
+        if (retval < 0) {
+                cs->hw_mode = hw_mode; /* Restore settings */
+                return retval;
+        }
+        return 0;
+}
+
+static void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+        u16 len;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__,
+                in_be16(&mspi->rx_bd->cbd_datlen), mspi->count);
+
+        len = in_be16(&mspi->rx_bd->cbd_datlen);
+        if (len > mspi->count) {
+                WARN_ON(1);
+                len = mspi->count;
+        }
+
+        /* Clear the events */
+        mpc8xxx_spi_write_reg(&reg_base->event, events);
+
+        mspi->count -= len;
+        if (mspi->count)
+                fsl_spi_cpm_bufs_start(mspi);
+        else
+                complete(&mspi->done);
+}
+
+static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        /* We need handle RX first */
+        if (events & SPIE_NE) {
+                u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
+
+                if (mspi->rx)
+                        mspi->get_rx(rx_data, mspi);
+        }
+
+        if ((events & SPIE_NF) == 0)
+                /* spin until TX is done */
+                while (((events =
+                        mpc8xxx_spi_read_reg(&reg_base->event)) &
+                                                SPIE_NF) == 0)
+                        cpu_relax();
+
+        /* Clear the events */
+        mpc8xxx_spi_write_reg(&reg_base->event, events);
+
+        mspi->count -= 1;
+        if (mspi->count) {
+                u32 word = mspi->get_tx(mspi);
+
+                mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+        } else {
+                complete(&mspi->done);
+        }
+}
+
+static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
+{
+        struct mpc8xxx_spi *mspi = context_data;
+        irqreturn_t ret = IRQ_NONE;
+        u32 events;
+        struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+        /* Get interrupt events(tx/rx) */
+        events = mpc8xxx_spi_read_reg(&reg_base->event);
+        if (events)
+                ret = IRQ_HANDLED;
+
+        dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
+
+        if (mspi->flags & SPI_CPM_MODE)
+                fsl_spi_cpm_irq(mspi, events);
+        else
+                fsl_spi_cpu_irq(mspi, events);
+
+        return ret;
+}
+
+static void *fsl_spi_alloc_dummy_rx(void)
+{
+        mutex_lock(&fsl_dummy_rx_lock);
+
+        if (!fsl_dummy_rx)
+                fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL);
+        if (fsl_dummy_rx)
+                fsl_dummy_rx_refcnt++;
+
+        mutex_unlock(&fsl_dummy_rx_lock);
+
+        return fsl_dummy_rx;
+}
+
+static void fsl_spi_free_dummy_rx(void)
+{
+        mutex_lock(&fsl_dummy_rx_lock);
+
+        switch (fsl_dummy_rx_refcnt) {
+        case 0:
+                WARN_ON(1);
+                break;
+        case 1:
+                kfree(fsl_dummy_rx);
+                fsl_dummy_rx = NULL;
+                /* fall through */
+        default:
+                fsl_dummy_rx_refcnt--;
+                break;
+        }
+
+        mutex_unlock(&fsl_dummy_rx_lock);
+}
+
+static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
+{
+        struct device *dev = mspi->dev;
+        struct device_node *np = dev->of_node;
+        const u32 *iprop;
+        int size;
+        void __iomem *spi_base;
+        unsigned long pram_ofs = -ENOMEM;
+
+        /* Can't use of_address_to_resource(), QE muram isn't at 0. */
+        iprop = of_get_property(np, "reg", &size);
+
+        /* QE with a fixed pram location? */
+        if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4)
+                return cpm_muram_alloc_fixed(iprop[2], SPI_PRAM_SIZE);
+
+        /* QE but with a dynamic pram location? */
+        if (mspi->flags & SPI_QE) {
+                pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
+                qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, mspi->subblock,
+                                QE_CR_PROTOCOL_UNSPECIFIED, pram_ofs);
+                return pram_ofs;
+        }
+
+        spi_base = of_iomap(np, 1);
+        if (spi_base == NULL)
+                return -EINVAL;
+
+        if (mspi->flags & SPI_CPM2) {
+                pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
+                out_be16(spi_base, pram_ofs);
+        } else {
+                struct spi_pram __iomem *pram = spi_base;
+                u16 rpbase = in_be16(&pram->rpbase);
+
+                /* Microcode relocation patch applied? */
+                if (rpbase)
+                        pram_ofs = rpbase;
+                else {
+                        pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
+                        out_be16(spi_base, pram_ofs);
+                }
+        }
+
+        iounmap(spi_base);
+        return pram_ofs;
+}
+
+static int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi)
+{
+        struct device *dev = mspi->dev;
+        struct device_node *np = dev->of_node;
+        const u32 *iprop;
+        int size;
+        unsigned long pram_ofs;
+        unsigned long bds_ofs;
+
+        if (!(mspi->flags & SPI_CPM_MODE))
+                return 0;
+
+        if (!fsl_spi_alloc_dummy_rx())
+                return -ENOMEM;
+
+        if (mspi->flags & SPI_QE) {
+                iprop = of_get_property(np, "cell-index", &size);
+                if (iprop && size == sizeof(*iprop))
+                        mspi->subblock = *iprop;
+
+                switch (mspi->subblock) {
+                default:
+                        dev_warn(dev, "cell-index unspecified, assuming SPI1");
+                        /* fall through */
+                case 0:
+                        mspi->subblock = QE_CR_SUBBLOCK_SPI1;
+                        break;
+                case 1:
+                        mspi->subblock = QE_CR_SUBBLOCK_SPI2;
+                        break;
+                }
+        }
+
+        pram_ofs = fsl_spi_cpm_get_pram(mspi);
+        if (IS_ERR_VALUE(pram_ofs)) {
+                dev_err(dev, "can't allocate spi parameter ram\n");
+                goto err_pram;
+        }
+
+        bds_ofs = cpm_muram_alloc(sizeof(*mspi->tx_bd) +
+                                  sizeof(*mspi->rx_bd), 8);
+        if (IS_ERR_VALUE(bds_ofs)) {
+                dev_err(dev, "can't allocate bds\n");
+                goto err_bds;
+        }
+
+        mspi->dma_dummy_tx = dma_map_single(dev, empty_zero_page, PAGE_SIZE,
+                                            DMA_TO_DEVICE);
+        if (dma_mapping_error(dev, mspi->dma_dummy_tx)) {
+                dev_err(dev, "unable to map dummy tx buffer\n");
+                goto err_dummy_tx;
+        }
+
+        mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR,
+                                            DMA_FROM_DEVICE);
+        if (dma_mapping_error(dev, mspi->dma_dummy_rx)) {
+                dev_err(dev, "unable to map dummy rx buffer\n");
+                goto err_dummy_rx;
+        }
+
+        mspi->pram = cpm_muram_addr(pram_ofs);
+
+        mspi->tx_bd = cpm_muram_addr(bds_ofs);
+        mspi->rx_bd = cpm_muram_addr(bds_ofs + sizeof(*mspi->tx_bd));
+
+        /* Initialize parameter ram. */
+        out_be16(&mspi->pram->tbase, cpm_muram_offset(mspi->tx_bd));
+        out_be16(&mspi->pram->rbase, cpm_muram_offset(mspi->rx_bd));
+        out_8(&mspi->pram->tfcr, CPMFCR_EB | CPMFCR_GBL);
+        out_8(&mspi->pram->rfcr, CPMFCR_EB | CPMFCR_GBL);
+        out_be16(&mspi->pram->mrblr, SPI_MRBLR);
+        out_be32(&mspi->pram->rstate, 0);
+        out_be32(&mspi->pram->rdp, 0);
+        out_be16(&mspi->pram->rbptr, 0);
+        out_be16(&mspi->pram->rbc, 0);
+        out_be32(&mspi->pram->rxtmp, 0);
+        out_be32(&mspi->pram->tstate, 0);
+        out_be32(&mspi->pram->tdp, 0);
+        out_be16(&mspi->pram->tbptr, 0);
+        out_be16(&mspi->pram->tbc, 0);
+        out_be32(&mspi->pram->txtmp, 0);
+
+        return 0;
+
+err_dummy_rx:
+        dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
+err_dummy_tx:
+        cpm_muram_free(bds_ofs);
+err_bds:
+        cpm_muram_free(pram_ofs);
+err_pram:
+        fsl_spi_free_dummy_rx();
+        return -ENOMEM;
+}
+
+static void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi)
+{
+        struct device *dev = mspi->dev;
+
+        dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE);
+        dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
+        cpm_muram_free(cpm_muram_offset(mspi->tx_bd));
+        cpm_muram_free(cpm_muram_offset(mspi->pram));
+        fsl_spi_free_dummy_rx();
+}
+
+static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
+{
+        iounmap(mspi->reg_base);
+        fsl_spi_cpm_free(mspi);
+}
+
+static struct spi_master * __devinit fsl_spi_probe(struct device *dev,
+                struct resource *mem, unsigned int irq)
+{
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
+        struct spi_master *master;
+        struct mpc8xxx_spi *mpc8xxx_spi;
+        struct fsl_spi_reg *reg_base;
+        u32 regval;
+        int ret = 0;
+
+        master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
+        if (master == NULL) {
+                ret = -ENOMEM;
+                goto err;
+        }
+
+        dev_set_drvdata(dev, master);
+
+        ret = mpc8xxx_spi_probe(dev, mem, irq);
+        if (ret)
+                goto err_probe;
+
+        master->setup = fsl_spi_setup;
+
+        mpc8xxx_spi = spi_master_get_devdata(master);
+        mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
+        mpc8xxx_spi->spi_remove = fsl_spi_remove;
+
+
+        ret = fsl_spi_cpm_init(mpc8xxx_spi);
+        if (ret)
+                goto err_cpm_init;
+
+        if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+                mpc8xxx_spi->rx_shift = 16;
+                mpc8xxx_spi->tx_shift = 24;
+        }
+
+        mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
+        if (mpc8xxx_spi->reg_base == NULL) {
+                ret = -ENOMEM;
+                goto err_ioremap;
+        }
+
+        /* Register for SPI Interrupt */
+        ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
+                          0, "fsl_spi", mpc8xxx_spi);
+
+        if (ret != 0)
+                goto free_irq;
+
+        reg_base = mpc8xxx_spi->reg_base;
+
+        /* SPI controller initializations */
+        mpc8xxx_spi_write_reg(&reg_base->mode, 0);
+        mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+        mpc8xxx_spi_write_reg(&reg_base->command, 0);
+        mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
+
+        /* Enable SPI interface */
+        regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+        if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
+                regval |= SPMODE_OP;
+
+        mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+        ret = spi_register_master(master);
+        if (ret < 0)
+                goto unreg_master;
+
+        dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
+                 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
+
+        return master;
+
+unreg_master:
+        free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
+free_irq:
+        iounmap(mpc8xxx_spi->reg_base);
+err_ioremap:
+        fsl_spi_cpm_free(mpc8xxx_spi);
+err_cpm_init:
+err_probe:
+        spi_master_put(master);
+err:
+        return ERR_PTR(ret);
+}
+
+static void fsl_spi_cs_control(struct spi_device *spi, bool on)
+{
+        struct device *dev = spi->dev.parent;
+        struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
+        u16 cs = spi->chip_select;
+        int gpio = pinfo->gpios[cs];
+        bool alow = pinfo->alow_flags[cs];
+
+        gpio_set_value(gpio, on ^ alow);
+}
+
+static int of_fsl_spi_get_chipselects(struct device *dev)
+{
+        struct device_node *np = dev->of_node;
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
+        struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+        unsigned int ngpios;
+        int i = 0;
+        int ret;
+
+        ngpios = of_gpio_count(np);
+        if (!ngpios) {
+                /*
+                 * SPI w/o chip-select line. One SPI device is still permitted
+                 * though.
+                 */
+                pdata->max_chipselect = 1;
+                return 0;
+        }
+
+        pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
+        if (!pinfo->gpios)
+                return -ENOMEM;
+        memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
+
+        pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
+                                    GFP_KERNEL);
+        if (!pinfo->alow_flags) {
+                ret = -ENOMEM;
+                goto err_alloc_flags;
+        }
+
+        for (; i < ngpios; i++) {
+                int gpio;
+                enum of_gpio_flags flags;
+
+                gpio = of_get_gpio_flags(np, i, &flags);
+                if (!gpio_is_valid(gpio)) {
+                        dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
+                        ret = gpio;
+                        goto err_loop;
+                }
+
+                ret = gpio_request(gpio, dev_name(dev));
+                if (ret) {
+                        dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
+                        goto err_loop;
+                }
+
+                pinfo->gpios[i] = gpio;
+                pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
+
+                ret = gpio_direction_output(pinfo->gpios[i],
+                                            pinfo->alow_flags[i]);
+                if (ret) {
+                        dev_err(dev, "can't set output direction for gpio "
+                                "#%d: %d\n", i, ret);
+                        goto err_loop;
+                }
+        }
+
+        pdata->max_chipselect = ngpios;
+        pdata->cs_control = fsl_spi_cs_control;
+
+        return 0;
+
+err_loop:
+        while (i >= 0) {
+                if (gpio_is_valid(pinfo->gpios[i]))
+                        gpio_free(pinfo->gpios[i]);
+                i--;
+        }
+
+        kfree(pinfo->alow_flags);
+        pinfo->alow_flags = NULL;
+err_alloc_flags:
+        kfree(pinfo->gpios);
+        pinfo->gpios = NULL;
+        return ret;
+}
+
+static int of_fsl_spi_free_chipselects(struct device *dev)
+{
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
+        struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+        int i;
+
+        if (!pinfo->gpios)
+                return 0;
+
+        for (i = 0; i < pdata->max_chipselect; i++) {
+                if (gpio_is_valid(pinfo->gpios[i]))
+                        gpio_free(pinfo->gpios[i]);
+        }
+
+        kfree(pinfo->gpios);
+        kfree(pinfo->alow_flags);
+        return 0;
+}
+
+static int __devinit of_fsl_spi_probe(struct platform_device *ofdev)
+{
+        struct device *dev = &ofdev->dev;
+        struct device_node *np = ofdev->dev.of_node;
+        struct spi_master *master;
+        struct resource mem;
+        struct resource irq;
+        int ret = -ENOMEM;
+
+        ret = of_mpc8xxx_spi_probe(ofdev);
+        if (ret)
+                return ret;
+
+        ret = of_fsl_spi_get_chipselects(dev);
+        if (ret)
+                goto err;
+
+        ret = of_address_to_resource(np, 0, &mem);
+        if (ret)
+                goto err;
+
+        ret = of_irq_to_resource(np, 0, &irq);
+        if (!ret) {
+                ret = -EINVAL;
+                goto err;
+        }
+
+        master = fsl_spi_probe(dev, &mem, irq.start);
+        if (IS_ERR(master)) {
+                ret = PTR_ERR(master);
+                goto err;
+        }
+
+        return 0;
+
+err:
+        of_fsl_spi_free_chipselects(dev);
+        return ret;
+}
+
+static int __devexit of_fsl_spi_remove(struct platform_device *ofdev)
+{
+        int ret;
+
+        ret = mpc8xxx_spi_remove(&ofdev->dev);
+        if (ret)
+                return ret;
+        of_fsl_spi_free_chipselects(&ofdev->dev);
+        return 0;
+}
+
+static const struct of_device_id of_fsl_spi_match[] = {
+        { .compatible = "fsl,spi" },
+        {}
+};
+MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
+
+static struct platform_driver of_fsl_spi_driver = {
+        .driver = {
+                .name = "fsl_spi",
+                .owner = THIS_MODULE,
+                .of_match_table = of_fsl_spi_match,
+        },
+        .probe          = of_fsl_spi_probe,
+        .remove         = __devexit_p(of_fsl_spi_remove),
+};
+
+#ifdef CONFIG_MPC832x_RDB
+/*
+ * XXX XXX XXX
+ * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
+ * only. The driver should go away soon, since newer MPC8323E-RDB's device
+ * tree can work with OpenFirmware driver. But for now we support old trees
+ * as well.
+ */
+static int __devinit plat_mpc8xxx_spi_probe(struct platform_device *pdev)
+{
+        struct resource *mem;
+        int irq;
+        struct spi_master *master;
+
+        if (!pdev->dev.platform_data)
+                return -EINVAL;
+
+        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!mem)
+                return -EINVAL;
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq <= 0)
+                return -EINVAL;
+
+        master = fsl_spi_probe(&pdev->dev, mem, irq);
+        if (IS_ERR(master))
+                return PTR_ERR(master);
+        return 0;
+}
+
+static int __devexit plat_mpc8xxx_spi_remove(struct platform_device *pdev)
+{
+        return mpc8xxx_spi_remove(&pdev->dev);
+}
+
+MODULE_ALIAS("platform:mpc8xxx_spi");
+static struct platform_driver mpc8xxx_spi_driver = {
+        .probe = plat_mpc8xxx_spi_probe,
+        .remove = __devexit_p(plat_mpc8xxx_spi_remove),
+        .driver = {
+                .name = "mpc8xxx_spi",
+                .owner = THIS_MODULE,
+        },
+};
+
+static bool legacy_driver_failed;
+
+static void __init legacy_driver_register(void)
+{
+        legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
+}
+
+static void __exit legacy_driver_unregister(void)
+{
+        if (legacy_driver_failed)
+                return;
+        platform_driver_unregister(&mpc8xxx_spi_driver);
+}
+#else
+static void __init legacy_driver_register(void) {}
+static void __exit legacy_driver_unregister(void) {}
+#endif /* CONFIG_MPC832x_RDB */
+
+static int __init fsl_spi_init(void)
+{
+        legacy_driver_register();
+        return platform_driver_register(&of_fsl_spi_driver);
+}
+module_init(fsl_spi_init);
+
+static void __exit fsl_spi_exit(void)
+{
+        platform_driver_unregister(&of_fsl_spi_driver);
+        legacy_driver_unregister();
+}
+module_exit(fsl_spi_exit);
+
+MODULE_AUTHOR("Kumar Gala");
+MODULE_DESCRIPTION("Simple Freescale SPI Driver");
+MODULE_LICENSE("GPL");