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path: root/drivers/spi/spi-fsl-cpm.c
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Diffstat (limited to 'drivers/spi/spi-fsl-cpm.c')
-rw-r--r--drivers/spi/spi-fsl-cpm.c424
1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/spi/spi-fsl-cpm.c b/drivers/spi/spi-fsl-cpm.c
new file mode 100644
index 000000000..7832ce330
--- /dev/null
+++ b/drivers/spi/spi-fsl-cpm.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+#include <asm/cpm.h>
+#include <soc/fsl/qe/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 <linux/byteorder/generic.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 (t->bits_per_word == 16 && t->tx_buf) {
+ const u16 *src = t->tx_buf;
+ u16 *dst;
+ int i;
+
+ dst = kmalloc(t->len, GFP_KERNEL);
+ if (!dst)
+ return -ENOMEM;
+
+ for (i = 0; i < t->len >> 1; i++)
+ dst[i] = cpu_to_le16p(src + i);
+
+ mspi->tx = dst;
+ mspi->map_tx_dma = 1;
+ }
+
+ 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;
+
+ if (t->bits_per_word == 16 && t->rx_buf) {
+ int i;
+
+ for (i = 0; i < t->len; i += 2)
+ le16_to_cpus(t->rx_buf + i);
+ }
+}
+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;
+ fallthrough;
+ 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");
+ fallthrough;
+ case 0:
+ mspi->subblock = QE_CR_SUBBLOCK_SPI1;
+ break;
+ case 1:
+ mspi->subblock = QE_CR_SUBBLOCK_SPI2;
+ break;
+ }
+ }
+
+ if (mspi->flags & SPI_CPM1) {
+ void *pram;
+
+ pram = devm_platform_ioremap_resource(to_platform_device(dev),
+ 1);
+ 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));
+ if (!(mspi->flags & SPI_CPM1))
+ cpm_muram_free(cpm_muram_offset(mspi->pram));
+ fsl_spi_free_dummy_rx();
+}
+EXPORT_SYMBOL_GPL(fsl_spi_cpm_free);
+
+MODULE_LICENSE("GPL");