4 files changed, 403 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/spi/spi-octeon.txt b/Documentation/devicetree/bindings/spi/spi-octeon.txt
new file mode 100644
index 000000000000..431add192342
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-octeon.txt
@@ -0,0 +1,33 @@
+Cavium, Inc. OCTEON SOC SPI master controller.
+
+Required properties:
+- compatible : "cavium,octeon-3010-spi"
+- reg : The register base for the controller.
+- interrupts : One interrupt, used by the controller.
+- #address-cells : <1>, as required by generic SPI binding.
+- #size-cells : <0>, also as required by generic SPI binding.
+
+Child nodes as per the generic SPI binding.
+
+Example:
+
+        spi@1070000001000 {
+                compatible = "cavium,octeon-3010-spi";
+                reg = <0x10700 0x00001000 0x0 0x100>;
+                interrupts = <0 58>;
+                #address-cells = <1>;
+                #size-cells = <0>;
+
+                eeprom@0 {
+                        compatible = "st,m95256", "atmel,at25";
+                        reg = <0>;
+                        spi-max-frequency = <5000000>;
+                        spi-cpha;
+                        spi-cpol;
+
+                        pagesize = <64>;
+                        size = <32768>;
+                        address-width = <16>;
+                };
+        };
+
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 5f84b5563c2d..d654f88f4cfb 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -237,6 +237,13 @@ config SPI_OC_TINY
         help
           This is the driver for OpenCores tiny SPI master controller.
 
+config SPI_OCTEON
+        tristate "Cavium OCTEON SPI controller"
+        depends on CPU_CAVIUM_OCTEON
+        help
+          SPI host driver for the hardware found on some Cavium OCTEON
+          SOCs.
+
 config SPI_OMAP_UWIRE
         tristate "OMAP1 MicroWire"
         depends on ARCH_OMAP1
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 3920dcf4c740..93d87bcdf3f5 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_SPI_MPC52xx_PSC)		+= spi-mpc52xx-psc.o
 obj-$(CONFIG_SPI_MPC52xx)               += spi-mpc52xx.o
 obj-$(CONFIG_SPI_NUC900)                += spi-nuc900.o
 obj-$(CONFIG_SPI_OC_TINY)               += spi-oc-tiny.o
+obj-$(CONFIG_SPI_OCTEON)                += spi-octeon.o
 obj-$(CONFIG_SPI_OMAP_UWIRE)            += spi-omap-uwire.o
 obj-$(CONFIG_SPI_OMAP_100K)             += spi-omap-100k.o
 obj-$(CONFIG_SPI_OMAP24XX)              += spi-omap2-mcspi.o
diff --git a/drivers/spi/spi-octeon.c b/drivers/spi/spi-octeon.c
new file mode 100644
index 000000000000..ea8fb2efb0f8
--- /dev/null
+++ b/drivers/spi/spi-octeon.c
@@ -0,0 +1,362 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2011, 2012 Cavium, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-mpi-defs.h>
+
+#define OCTEON_SPI_CFG 0
+#define OCTEON_SPI_STS 0x08
+#define OCTEON_SPI_TX 0x10
+#define OCTEON_SPI_DAT0 0x80
+
+#define OCTEON_SPI_MAX_BYTES 9
+
+#define OCTEON_SPI_MAX_CLOCK_HZ 16000000
+
+struct octeon_spi {
+        struct spi_master *my_master;
+        u64 register_base;
+        u64 last_cfg;
+        u64 cs_enax;
+};
+
+struct octeon_spi_setup {
+        u32 max_speed_hz;
+        u8 chip_select;
+        u8 mode;
+        u8 bits_per_word;
+};
+
+static void octeon_spi_wait_ready(struct octeon_spi *p)
+{
+        union cvmx_mpi_sts mpi_sts;
+        unsigned int loops = 0;
+
+        do {
+                if (loops++)
+                        __delay(500);
+                mpi_sts.u64 = cvmx_read_csr(p->register_base + OCTEON_SPI_STS);
+        } while (mpi_sts.s.busy);
+}
+
+static int octeon_spi_do_transfer(struct octeon_spi *p,
+                                  struct spi_message *msg,
+                                  struct spi_transfer *xfer,
+                                  bool last_xfer)
+{
+        union cvmx_mpi_cfg mpi_cfg;
+        union cvmx_mpi_tx mpi_tx;
+        unsigned int clkdiv;
+        unsigned int speed_hz;
+        int mode;
+        bool cpha, cpol;
+        int bits_per_word;
+        const u8 *tx_buf;
+        u8 *rx_buf;
+        int len;
+        int i;
+
+        struct octeon_spi_setup *msg_setup = spi_get_ctldata(msg->spi);
+
+        speed_hz = msg_setup->max_speed_hz;
+        mode = msg_setup->mode;
+        cpha = mode & SPI_CPHA;
+        cpol = mode & SPI_CPOL;
+        bits_per_word = msg_setup->bits_per_word;
+
+        if (xfer->speed_hz)
+                speed_hz = xfer->speed_hz;
+        if (xfer->bits_per_word)
+                bits_per_word = xfer->bits_per_word;
+
+        if (speed_hz > OCTEON_SPI_MAX_CLOCK_HZ)
+                speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
+
+        clkdiv = octeon_get_io_clock_rate() / (2 * speed_hz);
+
+        mpi_cfg.u64 = 0;
+
+        mpi_cfg.s.clkdiv = clkdiv;
+        mpi_cfg.s.cshi = (mode & SPI_CS_HIGH) ? 1 : 0;
+        mpi_cfg.s.lsbfirst = (mode & SPI_LSB_FIRST) ? 1 : 0;
+        mpi_cfg.s.wireor = (mode & SPI_3WIRE) ? 1 : 0;
+        mpi_cfg.s.idlelo = cpha != cpol;
+        mpi_cfg.s.cslate = cpha ? 1 : 0;
+        mpi_cfg.s.enable = 1;
+
+        if (msg_setup->chip_select < 4)
+                p->cs_enax |= 1ull << (12 + msg_setup->chip_select);
+        mpi_cfg.u64 |= p->cs_enax;
+
+        if (mpi_cfg.u64 != p->last_cfg) {
+                p->last_cfg = mpi_cfg.u64;
+                cvmx_write_csr(p->register_base + OCTEON_SPI_CFG, mpi_cfg.u64);
+        }
+        tx_buf = xfer->tx_buf;
+        rx_buf = xfer->rx_buf;
+        len = xfer->len;
+        while (len > OCTEON_SPI_MAX_BYTES) {
+                for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) {
+                        u8 d;
+                        if (tx_buf)
+                                d = *tx_buf++;
+                        else
+                                d = 0;
+                        cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d);
+                }
+                mpi_tx.u64 = 0;
+                mpi_tx.s.csid = msg_setup->chip_select;
+                mpi_tx.s.leavecs = 1;
+                mpi_tx.s.txnum = tx_buf ? OCTEON_SPI_MAX_BYTES : 0;
+                mpi_tx.s.totnum = OCTEON_SPI_MAX_BYTES;
+                cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64);
+
+                octeon_spi_wait_ready(p);
+                if (rx_buf)
+                        for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) {
+                                u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i));
+                                *rx_buf++ = (u8)v;
+                        }
+                len -= OCTEON_SPI_MAX_BYTES;
+        }
+
+        for (i = 0; i < len; i++) {
+                u8 d;
+                if (tx_buf)
+                        d = *tx_buf++;
+                else
+                        d = 0;
+                cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d);
+        }
+
+        mpi_tx.u64 = 0;
+        mpi_tx.s.csid = msg_setup->chip_select;
+        if (last_xfer)
+                mpi_tx.s.leavecs = xfer->cs_change;
+        else
+                mpi_tx.s.leavecs = !xfer->cs_change;
+        mpi_tx.s.txnum = tx_buf ? len : 0;
+        mpi_tx.s.totnum = len;
+        cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64);
+
+        octeon_spi_wait_ready(p);
+        if (rx_buf)
+                for (i = 0; i < len; i++) {
+                        u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i));
+                        *rx_buf++ = (u8)v;
+                }
+
+        if (xfer->delay_usecs)
+                udelay(xfer->delay_usecs);
+
+        return xfer->len;
+}
+
+static int octeon_spi_validate_bpw(struct spi_device *spi, u32 speed)
+{
+        switch (speed) {
+        case 8:
+                break;
+        default:
+                dev_err(&spi->dev, "Error: %d bits per word not supported\n",
+                        speed);
+                return -EINVAL;
+        }
+        return 0;
+}
+
+static int octeon_spi_transfer_one_message(struct spi_master *master,
+                                           struct spi_message *msg)
+{
+        struct octeon_spi *p = spi_master_get_devdata(master);
+        unsigned int total_len = 0;
+        int status = 0;
+        struct spi_transfer *xfer;
+
+        /*
+         * We better have set the configuration via a call to .setup
+         * before we get here.
+         */
+        if (spi_get_ctldata(msg->spi) == NULL) {
+                status = -EINVAL;
+                goto err;
+        }
+
+        list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+                if (xfer->bits_per_word) {
+                        status = octeon_spi_validate_bpw(msg->spi,
+                                                         xfer->bits_per_word);
+                        if (status)
+                                goto err;
+                }
+        }
+
+        list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+                bool last_xfer = &xfer->transfer_list == msg->transfers.prev;
+                int r = octeon_spi_do_transfer(p, msg, xfer, last_xfer);
+                if (r < 0) {
+                        status = r;
+                        goto err;
+                }
+                total_len += r;
+        }
+err:
+        msg->status = status;
+        msg->actual_length = total_len;
+        spi_finalize_current_message(master);
+        return status;
+}
+
+static struct octeon_spi_setup *octeon_spi_new_setup(struct spi_device *spi)
+{
+        struct octeon_spi_setup *setup = kzalloc(sizeof(*setup), GFP_KERNEL);
+        if (!setup)
+                return NULL;
+
+        setup->max_speed_hz = spi->max_speed_hz;
+        setup->chip_select = spi->chip_select;
+        setup->mode = spi->mode;
+        setup->bits_per_word = spi->bits_per_word;
+        return setup;
+}
+
+static int octeon_spi_setup(struct spi_device *spi)
+{
+        int r;
+        struct octeon_spi_setup *new_setup;
+        struct octeon_spi_setup *old_setup = spi_get_ctldata(spi);
+
+        r = octeon_spi_validate_bpw(spi, spi->bits_per_word);
+        if (r)
+                return r;
+
+        new_setup = octeon_spi_new_setup(spi);
+        if (!new_setup)
+                return -ENOMEM;
+
+        spi_set_ctldata(spi, new_setup);
+        kfree(old_setup);
+
+        return 0;
+}
+
+static void octeon_spi_cleanup(struct spi_device *spi)
+{
+        struct octeon_spi_setup *old_setup = spi_get_ctldata(spi);
+        spi_set_ctldata(spi, NULL);
+        kfree(old_setup);
+}
+
+static int octeon_spi_nop_transfer_hardware(struct spi_master *master)
+{
+        return 0;
+}
+
+static int __devinit octeon_spi_probe(struct platform_device *pdev)
+{
+
+        struct resource *res_mem;
+        struct spi_master *master;
+        struct octeon_spi *p;
+        int err = -ENOENT;
+
+        master = spi_alloc_master(&pdev->dev, sizeof(struct octeon_spi));
+        if (!master)
+                return -ENOMEM;
+        p = spi_master_get_devdata(master);
+        platform_set_drvdata(pdev, p);
+        p->my_master = master;
+
+        res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+        if (res_mem == NULL) {
+                dev_err(&pdev->dev, "found no memory resource\n");
+                err = -ENXIO;
+                goto fail;
+        }
+        if (!devm_request_mem_region(&pdev->dev, res_mem->start,
+                                     resource_size(res_mem), res_mem->name)) {
+                dev_err(&pdev->dev, "request_mem_region failed\n");
+                goto fail;
+        }
+        p->register_base = (u64)devm_ioremap(&pdev->dev, res_mem->start,
+                                             resource_size(res_mem));
+
+        /* Dynamic bus numbering */
+        master->bus_num = -1;
+        master->num_chipselect = 4;
+        master->mode_bits = SPI_CPHA |
+                            SPI_CPOL |
+                            SPI_CS_HIGH |
+                            SPI_LSB_FIRST |
+                            SPI_3WIRE;
+
+        master->setup = octeon_spi_setup;
+        master->cleanup = octeon_spi_cleanup;
+        master->prepare_transfer_hardware = octeon_spi_nop_transfer_hardware;
+        master->transfer_one_message = octeon_spi_transfer_one_message;
+        master->unprepare_transfer_hardware = octeon_spi_nop_transfer_hardware;
+
+        master->dev.of_node = pdev->dev.of_node;
+        err = spi_register_master(master);
+        if (err) {
+                dev_err(&pdev->dev, "register master failed: %d\n", err);
+                goto fail;
+        }
+
+        dev_info(&pdev->dev, "OCTEON SPI bus driver\n");
+
+        return 0;
+fail:
+        spi_master_put(master);
+        return err;
+}
+
+static int __devexit octeon_spi_remove(struct platform_device *pdev)
+{
+        struct octeon_spi *p = platform_get_drvdata(pdev);
+        u64 register_base = p->register_base;
+
+        spi_unregister_master(p->my_master);
+
+        /* Clear the CSENA* and put everything in a known state. */
+        cvmx_write_csr(register_base + OCTEON_SPI_CFG, 0);
+
+        return 0;
+}
+
+static struct of_device_id octeon_spi_match[] = {
+        { .compatible = "cavium,octeon-3010-spi", },
+        {},
+};
+MODULE_DEVICE_TABLE(of, octeon_spi_match);
+
+static struct platform_driver octeon_spi_driver = {
+        .driver = {
+                .name           = "spi-octeon",
+                .owner          = THIS_MODULE,
+                .of_match_table = octeon_spi_match,
+        },
+        .probe          = octeon_spi_probe,
+        .remove         = __devexit_p(octeon_spi_remove),
+};
+
+module_platform_driver(octeon_spi_driver);
+
+MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver");
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL");