diff options
Diffstat (limited to 'drivers/spi/spi-fsl-cpm.c')
| -rw-r--r-- | drivers/spi/spi-fsl-cpm.c | 387 | 
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/spi/spi-fsl-cpm.c b/drivers/spi/spi-fsl-cpm.c new file mode 100644 index 00000000000..07971e3fe58 --- /dev/null +++ b/drivers/spi/spi-fsl-cpm.c @@ -0,0 +1,387 @@ +/* + * Freescale SPI controller driver cpm functions. + * + * 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/types.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/fsl_devices.h> +#include <linux/dma-mapping.h> +#include <asm/cpm.h> +#include <asm/qe.h> + +#include "spi-fsl-lib.h" +#include "spi-fsl-cpm.h" +#include "spi-fsl-spi.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 + +#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; + +void fsl_spi_cpm_reinit_txrx(struct mpc8xxx_spi *mspi) +{ +	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)); +		} +	} +} + +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(®_base->command, SPCOM_STR); +} + +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(®_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; +} + +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; +} + +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(®_base->event, events); + +	mspi->count -= len; +	if (mspi->count) +		fsl_spi_cpm_bufs_start(mspi); +	else +		complete(&mspi->done); +} + +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; +} + +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; +} + +void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi) +{ +	struct device *dev = mspi->dev; + +	if (!(mspi->flags & SPI_CPM_MODE)) +		return; + +	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(); +}  |