- Add SPI bus driver for ar71xx SoC

1 files changed, 228 insertions, 0 deletions

diff --git a/sys/mips/atheros/ar71xx_spi.c b/sys/mips/atheros/ar71xx_spi.c
new file mode 100644
index 000000000000..9f7eb1acd87a
--- /dev/null
+++ b/sys/mips/atheros/ar71xx_spi.c
@@ -0,0 +1,228 @@
+/*-
+ * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice unmodified, this list of conditions, and the following
+ *    disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+
+#include <sys/bus.h>
+#include <sys/interrupt.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/rman.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+#include <vm/vm_extern.h>
+
+#include <machine/bus.h>
+#include <machine/cpu.h>
+#include <machine/pmap.h>
+
+#include <dev/spibus/spi.h>
+#include <dev/spibus/spibusvar.h>
+#include "spibus_if.h"
+
+#include <mips/atheros/ar71xxreg.h>
+
+#undef AR71XX_SPI_DEBUG
+#ifdef AR71XX_SPI_DEBUG
+#define dprintf printf
+#else
+#define dprintf(x, arg...)
+#endif
+
+/*
+ * register space access macros
+ */
+#define SPI_WRITE(sc, reg, val)	do {	\
+		bus_write_4(sc->sc_mem_res, (reg), (val)); \
+	} while (0)
+
+#define SPI_READ(sc, reg)	 bus_read_4(sc->sc_mem_res, (reg))
+
+#define SPI_SET_BITS(sc, reg, bits)	\
+	SPI_WRITE(sc, reg, SPI_READ(sc, (reg)) | (bits))
+
+#define SPI_CLEAR_BITS(sc, reg, bits)	\
+	SPI_WRITE(sc, reg, SPI_READ(sc, (reg)) & ~(bits))
+
+struct ar71xx_spi_softc {
+	device_t		sc_dev;
+	struct resource		*sc_mem_res;
+	uint32_t		sc_reg_ioctrl;
+};
+
+static int
+ar71xx_spi_probe(device_t dev)
+{
+	device_set_desc(dev, "AR71XX SPI");
+	return (0);
+}
+
+static int
+ar71xx_spi_attach(device_t dev)
+{
+	struct ar71xx_spi_softc *sc = device_get_softc(dev);
+	int rid;
+
+	sc->sc_dev = dev;
+        rid = 0;
+	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 
+	    RF_ACTIVE);
+	if (!sc->sc_mem_res) {
+		device_printf(dev, "Could not map memory\n");
+		return (ENXIO);
+	}
+
+	sc->sc_reg_ioctrl  = SPI_READ(sc, AR71XX_SPI_IO_CTRL);
+
+	SPI_WRITE(sc, AR71XX_SPI_IO_CTRL, SPI_IO_CTRL_CS0 | SPI_IO_CTRL_CS1 |
+	    SPI_IO_CTRL_CS2);
+	SPI_WRITE(sc, AR71XX_SPI_CTRL, sc->sc_reg_ioctrl);
+	SPI_WRITE(sc, AR71XX_SPI_FS, 0);
+
+	device_add_child(dev, "spibus", 0);
+	return (bus_generic_attach(dev));
+}
+
+static void
+ar71xx_spi_chip_activate(struct ar71xx_spi_softc *sc, int cs)
+{
+	uint32_t ioctrl = SPI_IO_CTRL_CS0 |SPI_IO_CTRL_CS1 | SPI_IO_CTRL_CS2;
+	/*
+	 * Put respective CSx to low
+	 */
+	ioctrl &= ~(SPI_IO_CTRL_CS0 << cs);
+
+	SPI_WRITE(sc, AR71XX_SPI_FS, 1);
+	SPI_WRITE(sc, AR71XX_SPI_CTRL, 0x43);
+	SPI_WRITE(sc, AR71XX_SPI_IO_CTRL, ioctrl);
+}
+
+static void
+ar71xx_spi_chip_deactivate(struct ar71xx_spi_softc *sc, int cs)
+{
+	/*
+	 * Put all CSx to high
+	 */
+	SPI_WRITE(sc, AR71XX_SPI_IO_CTRL, SPI_IO_CTRL_CS0 | SPI_IO_CTRL_CS1 |
+	    SPI_IO_CTRL_CS2);
+	SPI_WRITE(sc, AR71XX_SPI_CTRL, sc->sc_reg_ioctrl);
+	SPI_WRITE(sc, AR71XX_SPI_FS, 0);
+}
+
+static uint8_t
+ar71xx_spi_txrx(struct ar71xx_spi_softc *sc, uint8_t data)
+{
+	int bit;
+	/* CS0 */
+	uint32_t ioctrl = SPI_IO_CTRL_CS1 | SPI_IO_CTRL_CS2;
+
+	uint32_t iod, rds;
+	for (bit = 7; bit >=0; bit--) {
+		if (data & (1 << bit))
+			iod = ioctrl | SPI_IO_CTRL_DO;
+		else
+			iod = ioctrl & ~SPI_IO_CTRL_DO;
+		SPI_WRITE(sc, AR71XX_SPI_IO_CTRL, iod);
+		SPI_WRITE(sc, AR71XX_SPI_IO_CTRL, iod | SPI_IO_CTRL_CLK);
+	}
+
+	rds = SPI_READ(sc, AR71XX_SPI_RDS);
+
+	return (rds & 0xff);
+}
+
+static int
+ar71xx_spi_transfer(device_t dev, device_t child, struct spi_command *cmd)
+{
+	struct ar71xx_spi_softc *sc;
+	uint8_t *buf_in, *buf_out;
+	struct spibus_ivar *devi = SPIBUS_IVAR(child);
+	int i;
+
+	sc = device_get_softc(dev);
+
+	ar71xx_spi_chip_activate(sc, devi->cs);
+
+	KASSERT(cmd->tx_cmd_sz == cmd->rx_cmd_sz, 
+	    ("TX/RX command sizes should be equal"));
+	KASSERT(cmd->tx_data_sz == cmd->rx_data_sz, 
+	    ("TX/RX data sizes should be equal"));
+
+	/*
+	 * Transfer command
+	 */
+	buf_out = (uint8_t *)cmd->tx_cmd;
+	buf_in = (uint8_t *)cmd->rx_cmd;
+	for (i = 0; i < cmd->tx_cmd_sz; i++)
+		buf_in[i] = ar71xx_spi_txrx(sc, buf_out[i]);
+
+	/*
+	 * Receive/transmit data (depends on  command)
+	 */
+	buf_out = (uint8_t *)cmd->tx_data;
+	buf_in = (uint8_t *)cmd->rx_data;
+	for (i = 0; i < cmd->tx_data_sz; i++)
+		buf_in[i] = ar71xx_spi_txrx(sc, buf_out[i]);
+
+	ar71xx_spi_chip_deactivate(sc, devi->cs);
+
+	return (0);
+}
+
+static int
+ar71xx_spi_detach(device_t dev)
+{
+
+	return (EBUSY);	/* XXX */
+}
+
+static device_method_t ar71xx_spi_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		ar71xx_spi_probe),
+	DEVMETHOD(device_attach,	ar71xx_spi_attach),
+	DEVMETHOD(device_detach,	ar71xx_spi_detach),
+
+	DEVMETHOD(spibus_transfer,	ar71xx_spi_transfer),
+
+	{0, 0}
+};
+
+static driver_t ar71xx_spi_driver = {
+	"spi",
+	ar71xx_spi_methods,
+	sizeof(struct ar71xx_spi_softc),
+};
+
+static devclass_t ar71xx_spi_devclass;
+
+DRIVER_MODULE(ar71xx_spi, nexus, ar71xx_spi_driver, ar71xx_spi_devclass, 0, 0);