diff options
Diffstat (limited to 'drivers/spi/spi_fsl_spi.c')
| -rw-r--r-- | drivers/spi/spi_fsl_spi.c | 1425 |
1 files changed, 1425 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..1dd86b835cd8 --- /dev/null +++ b/drivers/spi/spi_fsl_spi.c @@ -0,0 +1,1425 @@ +/* + * MPC8xxx SPI controller driver. + * + * Maintainer: Kumar Gala + * + * Copyright (C) 2006 Polycom, 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/init.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/bug.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/completion.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/irq.h> +#include <linux/device.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 <linux/slab.h> + +#include <sysdev/fsl_soc.h> +#include <asm/cpm.h> +#include <asm/qe.h> +#include <asm/irq.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 mpc8xxx_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) + +/* SPI Controller driver's private data. */ +struct mpc8xxx_spi { + struct device *dev; + struct mpc8xxx_spi_reg __iomem *base; + + /* rx & tx bufs from the spi_transfer */ + const void *tx; + void *rx; + + int subblock; + struct spi_pram __iomem *pram; + struct cpm_buf_desc __iomem *tx_bd; + struct cpm_buf_desc __iomem *rx_bd; + + struct spi_transfer *xfer_in_progress; + + /* dma addresses for CPM transfers */ + dma_addr_t tx_dma; + dma_addr_t rx_dma; + bool map_tx_dma; + bool map_rx_dma; + + dma_addr_t dma_dummy_tx; + dma_addr_t dma_dummy_rx; + + /* functions to deal with different sized buffers */ + void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *); + u32(*get_tx) (struct mpc8xxx_spi *); + + unsigned int count; + unsigned int irq; + + unsigned nsecs; /* (clock cycle time)/2 */ + + u32 spibrg; /* SPIBRG input clock */ + u32 rx_shift; /* RX data reg shift when in qe mode */ + u32 tx_shift; /* TX data reg shift when in qe mode */ + + unsigned int flags; + + struct workqueue_struct *workqueue; + struct work_struct work; + + struct list_head queue; + spinlock_t lock; + + struct completion done; +}; + +static void *mpc8xxx_dummy_rx; +static DEFINE_MUTEX(mpc8xxx_dummy_rx_lock); +static int mpc8xxx_dummy_rx_refcnt; + +struct spi_mpc8xxx_cs { + /* functions to deal with different sized buffers */ + void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *); + u32 (*get_tx) (struct mpc8xxx_spi *); + u32 rx_shift; /* RX data reg shift when in qe mode */ + u32 tx_shift; /* TX data reg shift when in qe mode */ + u32 hw_mode; /* Holds HW mode register settings */ +}; + +static inline void mpc8xxx_spi_write_reg(__be32 __iomem *reg, u32 val) +{ + out_be32(reg, val); +} + +static inline u32 mpc8xxx_spi_read_reg(__be32 __iomem *reg) +{ + return in_be32(reg); +} + +#define MPC83XX_SPI_RX_BUF(type) \ +static \ +void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \ +{ \ + type *rx = mpc8xxx_spi->rx; \ + *rx++ = (type)(data >> mpc8xxx_spi->rx_shift); \ + mpc8xxx_spi->rx = rx; \ +} + +#define MPC83XX_SPI_TX_BUF(type) \ +static \ +u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi) \ +{ \ + u32 data; \ + const type *tx = mpc8xxx_spi->tx; \ + if (!tx) \ + return 0; \ + data = *tx++ << mpc8xxx_spi->tx_shift; \ + mpc8xxx_spi->tx = tx; \ + return data; \ +} + +MPC83XX_SPI_RX_BUF(u8) +MPC83XX_SPI_RX_BUF(u16) +MPC83XX_SPI_RX_BUF(u32) +MPC83XX_SPI_TX_BUF(u8) +MPC83XX_SPI_TX_BUF(u16) +MPC83XX_SPI_TX_BUF(u32) + +static void mpc8xxx_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; + __be32 __iomem *mode = &mspi->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 mpc8xxx_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; + + mpc8xxx_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 mpc8xxx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + int bits_per_word; + u8 pm; + u32 hz; + 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; + } else { + bits_per_word = 0; + hz = 0; + } + + /* 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); + + mpc8xxx_spi_change_mode(spi); + return 0; +} + +static void mpc8xxx_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; + + 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(&mspi->base->command, SPCOM_STR); +} + +static int mpc8xxx_spi_cpm_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, bool is_dma_mapped) +{ + struct device *dev = mspi->dev; + + 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(&mspi->base->mask, SPIE_RXB); + + mspi->xfer_in_progress = t; + mspi->count = t->len; + + /* start CPM transfers */ + mpc8xxx_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 mpc8xxx_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 mpc8xxx_spi_cpu_bufs(struct mpc8xxx_spi *mspi, + struct spi_transfer *t, unsigned int len) +{ + u32 word; + + mspi->count = len; + + /* enable rx ints */ + mpc8xxx_spi_write_reg(&mspi->base->mask, SPIM_NE); + + /* transmit word */ + word = mspi->get_tx(mspi); + mpc8xxx_spi_write_reg(&mspi->base->transmit, word); + + return 0; +} + +static int mpc8xxx_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); + unsigned int len = t->len; + u8 bits_per_word; + int ret; + + 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 = mpc8xxx_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped); + else + ret = mpc8xxx_spi_cpu_bufs(mpc8xxx_spi, t, len); + if (ret) + return ret; + + wait_for_completion(&mpc8xxx_spi->done); + + /* disable rx ints */ + mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mask, 0); + + if (mpc8xxx_spi->flags & SPI_CPM_MODE) + mpc8xxx_spi_cpm_bufs_complete(mpc8xxx_spi); + + return mpc8xxx_spi->count; +} + +static void mpc8xxx_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 = mpc8xxx_spi_setup_transfer(spi, t); + if (status < 0) + break; + } + + if (cs_change) { + mpc8xxx_spi_chipselect(spi, BITBANG_CS_ACTIVE); + ndelay(nsecs); + } + cs_change = t->cs_change; + if (t->len) + status = mpc8xxx_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); + mpc8xxx_spi_chipselect(spi, BITBANG_CS_INACTIVE); + ndelay(nsecs); + } + } + + m->status = status; + m->complete(m->context); + + if (status || !cs_change) { + ndelay(nsecs); + mpc8xxx_spi_chipselect(spi, BITBANG_CS_INACTIVE); + } + + mpc8xxx_spi_setup_transfer(spi, NULL); +} + +static void mpc8xxx_spi_work(struct work_struct *work) +{ + struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi, + work); + + spin_lock_irq(&mpc8xxx_spi->lock); + while (!list_empty(&mpc8xxx_spi->queue)) { + struct spi_message *m = container_of(mpc8xxx_spi->queue.next, + struct spi_message, queue); + + list_del_init(&m->queue); + spin_unlock_irq(&mpc8xxx_spi->lock); + + mpc8xxx_spi_do_one_msg(m); + + spin_lock_irq(&mpc8xxx_spi->lock); + } + spin_unlock_irq(&mpc8xxx_spi->lock); +} + +static int mpc8xxx_spi_setup(struct spi_device *spi) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + 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); + + hw_mode = cs->hw_mode; /* Save original settings */ + cs->hw_mode = mpc8xxx_spi_read_reg(&mpc8xxx_spi->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 = mpc8xxx_spi_setup_transfer(spi, NULL); + if (retval < 0) { + cs->hw_mode = hw_mode; /* Restore settings */ + return retval; + } + return 0; +} + +static void mpc8xxx_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events) +{ + u16 len; + + 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(&mspi->base->event, events); + + mspi->count -= len; + if (mspi->count) + mpc8xxx_spi_cpm_bufs_start(mspi); + else + complete(&mspi->done); +} + +static void mpc8xxx_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) +{ + /* We need handle RX first */ + if (events & SPIE_NE) { + u32 rx_data = mpc8xxx_spi_read_reg(&mspi->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(&mspi->base->event)) & + SPIE_NF) == 0) + cpu_relax(); + + /* Clear the events */ + mpc8xxx_spi_write_reg(&mspi->base->event, events); + + mspi->count -= 1; + if (mspi->count) { + u32 word = mspi->get_tx(mspi); + + mpc8xxx_spi_write_reg(&mspi->base->transmit, word); + } else { + complete(&mspi->done); + } +} + +static irqreturn_t mpc8xxx_spi_irq(s32 irq, void *context_data) +{ + struct mpc8xxx_spi *mspi = context_data; + irqreturn_t ret = IRQ_NONE; + u32 events; + + /* Get interrupt events(tx/rx) */ + events = mpc8xxx_spi_read_reg(&mspi->base->event); + if (events) + ret = IRQ_HANDLED; + + dev_dbg(mspi->dev, "%s: events %x\n", __func__, events); + + if (mspi->flags & SPI_CPM_MODE) + mpc8xxx_spi_cpm_irq(mspi, events); + else + mpc8xxx_spi_cpu_irq(mspi, events); + + return ret; +} + +static int mpc8xxx_spi_transfer(struct spi_device *spi, + struct spi_message *m) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + unsigned long flags; + + m->actual_length = 0; + m->status = -EINPROGRESS; + + spin_lock_irqsave(&mpc8xxx_spi->lock, flags); + list_add_tail(&m->queue, &mpc8xxx_spi->queue); + queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work); + spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags); + + return 0; +} + + +static void mpc8xxx_spi_cleanup(struct spi_device *spi) +{ + kfree(spi->controller_state); +} + +static void *mpc8xxx_spi_alloc_dummy_rx(void) +{ + mutex_lock(&mpc8xxx_dummy_rx_lock); + + if (!mpc8xxx_dummy_rx) + mpc8xxx_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL); + if (mpc8xxx_dummy_rx) + mpc8xxx_dummy_rx_refcnt++; + + mutex_unlock(&mpc8xxx_dummy_rx_lock); + + return mpc8xxx_dummy_rx; +} + +static void mpc8xxx_spi_free_dummy_rx(void) +{ + mutex_lock(&mpc8xxx_dummy_rx_lock); + + switch (mpc8xxx_dummy_rx_refcnt) { + case 0: + WARN_ON(1); + break; + case 1: + kfree(mpc8xxx_dummy_rx); + mpc8xxx_dummy_rx = NULL; + /* fall through */ + default: + mpc8xxx_dummy_rx_refcnt--; + break; + } + + mutex_unlock(&mpc8xxx_dummy_rx_lock); +} + +static unsigned long mpc8xxx_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; + unsigned long spi_base_ofs; + 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; + } + + /* CPM1 and CPM2 pram must be at a fixed addr. */ + if (!iprop || size != sizeof(*iprop) * 4) + return -ENOMEM; + + spi_base_ofs = cpm_muram_alloc_fixed(iprop[2], 2); + if (IS_ERR_VALUE(spi_base_ofs)) + return -ENOMEM; + + if (mspi->flags & SPI_CPM2) { + pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64); + if (!IS_ERR_VALUE(pram_ofs)) { + u16 __iomem *spi_base = cpm_muram_addr(spi_base_ofs); + + out_be16(spi_base, pram_ofs); + } + } else { + struct spi_pram __iomem *pram = cpm_muram_addr(spi_base_ofs); + u16 rpbase = in_be16(&pram->rpbase); + + /* Microcode relocation patch applied? */ + if (rpbase) + pram_ofs = rpbase; + else + return spi_base_ofs; + } + + cpm_muram_free(spi_base_ofs); + return pram_ofs; +} + +static int mpc8xxx_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 (!mpc8xxx_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 = mpc8xxx_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, mpc8xxx_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: + mpc8xxx_spi_free_dummy_rx(); + return -ENOMEM; +} + +static void mpc8xxx_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)); + mpc8xxx_spi_free_dummy_rx(); +} + +static const char *mpc8xxx_spi_strmode(unsigned int flags) +{ + if (flags & SPI_QE_CPU_MODE) { + return "QE CPU"; + } else if (flags & SPI_CPM_MODE) { + if (flags & SPI_QE) + return "QE"; + else if (flags & SPI_CPM2) + return "CPM2"; + else + return "CPM1"; + } + return "CPU"; +} + +static struct spi_master * __devinit +mpc8xxx_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; + 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); + + /* the spi->mode bits understood by this driver: */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH + | SPI_LSB_FIRST | SPI_LOOP; + + master->setup = mpc8xxx_spi_setup; + master->transfer = mpc8xxx_spi_transfer; + master->cleanup = mpc8xxx_spi_cleanup; + master->dev.of_node = dev->of_node; + + mpc8xxx_spi = spi_master_get_devdata(master); + mpc8xxx_spi->dev = dev; + mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8; + mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8; + mpc8xxx_spi->flags = pdata->flags; + mpc8xxx_spi->spibrg = pdata->sysclk; + + ret = mpc8xxx_spi_cpm_init(mpc8xxx_spi); + if (ret) + goto err_cpm_init; + + mpc8xxx_spi->rx_shift = 0; + mpc8xxx_spi->tx_shift = 0; + if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) { + mpc8xxx_spi->rx_shift = 16; + mpc8xxx_spi->tx_shift = 24; + } + + init_completion(&mpc8xxx_spi->done); + + mpc8xxx_spi->base = ioremap(mem->start, resource_size(mem)); + if (mpc8xxx_spi->base == NULL) { + ret = -ENOMEM; + goto err_ioremap; + } + + mpc8xxx_spi->irq = irq; + + /* Register for SPI Interrupt */ + ret = request_irq(mpc8xxx_spi->irq, mpc8xxx_spi_irq, + 0, "mpc8xxx_spi", mpc8xxx_spi); + + if (ret != 0) + goto unmap_io; + + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->max_chipselect; + + /* SPI controller initializations */ + mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mode, 0); + mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mask, 0); + mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->command, 0); + mpc8xxx_spi_write_reg(&mpc8xxx_spi->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(&mpc8xxx_spi->base->mode, regval); + spin_lock_init(&mpc8xxx_spi->lock); + init_completion(&mpc8xxx_spi->done); + INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work); + INIT_LIST_HEAD(&mpc8xxx_spi->queue); + + mpc8xxx_spi->workqueue = create_singlethread_workqueue( + dev_name(master->dev.parent)); + if (mpc8xxx_spi->workqueue == NULL) { + ret = -EBUSY; + goto free_irq; + } + + ret = spi_register_master(master); + if (ret < 0) + goto unreg_master; + + dev_info(dev, "at 0x%p (irq = %d), %s mode\n", mpc8xxx_spi->base, + mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags)); + + return master; + +unreg_master: + destroy_workqueue(mpc8xxx_spi->workqueue); +free_irq: + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); +unmap_io: + iounmap(mpc8xxx_spi->base); +err_ioremap: + mpc8xxx_spi_cpm_free(mpc8xxx_spi); +err_cpm_init: + spi_master_put(master); +err: + return ERR_PTR(ret); +} + +static int __devexit mpc8xxx_spi_remove(struct device *dev) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct spi_master *master; + + master = dev_get_drvdata(dev); + mpc8xxx_spi = spi_master_get_devdata(master); + + flush_workqueue(mpc8xxx_spi->workqueue); + destroy_workqueue(mpc8xxx_spi->workqueue); + spi_unregister_master(master); + + free_irq(mpc8xxx_spi->irq, mpc8xxx_spi); + iounmap(mpc8xxx_spi->base); + mpc8xxx_spi_cpm_free(mpc8xxx_spi); + + return 0; +} + +struct mpc8xxx_spi_probe_info { + struct fsl_spi_platform_data pdata; + int *gpios; + bool *alow_flags; +}; + +static struct mpc8xxx_spi_probe_info * +to_of_pinfo(struct fsl_spi_platform_data *pdata) +{ + return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata); +} + +static void mpc8xxx_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_mpc8xxx_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 = mpc8xxx_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_mpc8xxx_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_mpc8xxx_spi_probe(struct platform_device *ofdev, + const struct of_device_id *ofid) +{ + struct device *dev = &ofdev->dev; + struct device_node *np = ofdev->dev.of_node; + struct mpc8xxx_spi_probe_info *pinfo; + struct fsl_spi_platform_data *pdata; + struct spi_master *master; + struct resource mem; + struct resource irq; + const void *prop; + int ret = -ENOMEM; + + pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL); + if (!pinfo) + return -ENOMEM; + + pdata = &pinfo->pdata; + dev->platform_data = pdata; + + /* Allocate bus num dynamically. */ + pdata->bus_num = -1; + + /* SPI controller is either clocked from QE or SoC clock. */ + pdata->sysclk = get_brgfreq(); + if (pdata->sysclk == -1) { + pdata->sysclk = fsl_get_sys_freq(); + if (pdata->sysclk == -1) { + ret = -ENODEV; + goto err_clk; + } + } + + prop = of_get_property(np, "mode", NULL); + if (prop && !strcmp(prop, "cpu-qe")) + pdata->flags = SPI_QE_CPU_MODE; + else if (prop && !strcmp(prop, "qe")) + pdata->flags = SPI_CPM_MODE | SPI_QE; + else if (of_device_is_compatible(np, "fsl,cpm2-spi")) + pdata->flags = SPI_CPM_MODE | SPI_CPM2; + else if (of_device_is_compatible(np, "fsl,cpm1-spi")) + pdata->flags = SPI_CPM_MODE | SPI_CPM1; + + ret = of_mpc8xxx_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 = mpc8xxx_spi_probe(dev, &mem, irq.start); + if (IS_ERR(master)) { + ret = PTR_ERR(master); + goto err; + } + + return 0; + +err: + of_mpc8xxx_spi_free_chipselects(dev); +err_clk: + kfree(pinfo); + return ret; +} + +static int __devexit of_mpc8xxx_spi_remove(struct platform_device *ofdev) +{ + int ret; + + ret = mpc8xxx_spi_remove(&ofdev->dev); + if (ret) + return ret; + of_mpc8xxx_spi_free_chipselects(&ofdev->dev); + return 0; +} + +static const struct of_device_id of_mpc8xxx_spi_match[] = { + { .compatible = "fsl,spi" }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_mpc8xxx_spi_match); + +static struct of_platform_driver of_mpc8xxx_spi_driver = { + .driver = { + .name = "mpc8xxx_spi", + .owner = THIS_MODULE, + .of_match_table = of_mpc8xxx_spi_match, + }, + .probe = of_mpc8xxx_spi_probe, + .remove = __devexit_p(of_mpc8xxx_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 = mpc8xxx_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 mpc8xxx_spi_init(void) +{ + legacy_driver_register(); + return of_register_platform_driver(&of_mpc8xxx_spi_driver); +} + +static void __exit mpc8xxx_spi_exit(void) +{ + of_unregister_platform_driver(&of_mpc8xxx_spi_driver); + legacy_driver_unregister(); +} + +module_init(mpc8xxx_spi_init); +module_exit(mpc8xxx_spi_exit); + +MODULE_AUTHOR("Kumar Gala"); +MODULE_DESCRIPTION("Simple MPC8xxx SPI Driver"); +MODULE_LICENSE("GPL"); |