Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / spi / spi-fsl-cpm.c
diff --git a/kernel/drivers/spi/spi-fsl-cpm.c b/kernel/drivers/spi/spi-fsl-cpm.c
new file mode 100644 (file)
index 0000000..896add8
--- /dev/null
@@ -0,0 +1,406 @@
+/*
+ * 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 <asm/cpm.h>
+#include <asm/qe.h>
+#include <linux/dma-mapping.h>
+#include <linux/fsl_devices.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+
+#include "spi-fsl-cpm.h"
+#include "spi-fsl-lib.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 {
+               if (mspi->flags & SPI_CPM1) {
+                       out_be32(&mspi->pram->rstate, 0);
+                       out_be16(&mspi->pram->rbptr,
+                                in_be16(&mspi->pram->rbase));
+                       out_be32(&mspi->pram->tstate, 0);
+                       out_be16(&mspi->pram->tbptr,
+                                in_be16(&mspi->pram->tbase));
+               } else {
+                       cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX);
+               }
+       }
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_reinit_txrx);
+
+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);
+}
+
+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;
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs);
+
+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;
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_bufs_complete);
+
+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);
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_irq);
+
+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);
+       }
+
+       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 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\n");
+                       /* fall through */
+               case 0:
+                       mspi->subblock = QE_CR_SUBBLOCK_SPI1;
+                       break;
+               case 1:
+                       mspi->subblock = QE_CR_SUBBLOCK_SPI2;
+                       break;
+               }
+       }
+
+       if (mspi->flags & SPI_CPM1) {
+               struct resource *res;
+               void *pram;
+
+               res = platform_get_resource(to_platform_device(dev),
+                                           IORESOURCE_MEM, 1);
+               pram = devm_ioremap_resource(dev, res);
+               if (IS_ERR(pram))
+                       mspi->pram = NULL;
+               else
+                       mspi->pram = pram;
+       } else {
+               unsigned long pram_ofs = fsl_spi_cpm_get_pram(mspi);
+
+               if (IS_ERR_VALUE(pram_ofs))
+                       mspi->pram = NULL;
+               else
+                       mspi->pram = cpm_muram_addr(pram_ofs);
+       }
+       if (mspi->pram == NULL) {
+               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->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:
+       if (!(mspi->flags & SPI_CPM1))
+               cpm_muram_free(cpm_muram_offset(mspi->pram));
+err_pram:
+       fsl_spi_free_dummy_rx();
+       return -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_init);
+
+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();
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_free);
+
+MODULE_LICENSE("GPL");