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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 16:08:04 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 16:08:04 +0900
commitde390bba797aa9a554bc1769b6a8771605854d79 (patch)
treece95610d4a70ec0a7307a30cfd1a66fdf0c901ab /drivers/spi
parentMerge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic (diff)
parentMerge branch 'master' of git://dev.phrozen.org/mips-next into mips-for-linux-next (diff)
downloadlinux-dev-de390bba797aa9a554bc1769b6a8771605854d79.tar.xz
linux-dev-de390bba797aa9a554bc1769b6a8771605854d79.zip
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS update from Ralf Baechle: "This is the MIPS update for 3.7. A fair chunk of them are platform updates to the Cavium Octeon SOC (which involves machine generated header files of considerable size), Atheros ATH79xx, RMI aka Netlogic aka Broadcom XLP, Broadcom BCM63xx platforms. Support for the commercial MIPS simulator MIPSsim has been removed as MIPS Technologies is shifting away from this product and Qemu is offering various more powerful platforms. The generic MIPS code can now also probe for no-execute / write-only TLB features implemented without the full SmartMIPS extension as permitted by the latest MIPS processor architecture. Lots of small changes to generic code." * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (78 commits) MIPS: ath79: Fix CPU/DDR frequency calculation for SRIF PLLs MIPS: ath79: use correct fractional dividers for {CPU,DDR}_PLL on AR934x MIPS: BCM63XX: Properly handle mac address octet overflow MIPS: Kconfig: Avoid build errors by hiding USE_OF from the user. MIPS: Replace `-' in defconfig filename wth `_' for consistency. MIPS: Wire kcmp syscall. MIPS: MIPSsim: Remove the MIPSsim platform. MIPS: NOTIFY_RESUME is not needed in TIF masks MIPS: Merge the identical "return from syscall" per-ABI code MIPS: Unobfuscate _TIF..._MASK MIPS: Prevent hitting do_notify_resume() with !user_mode(regs). MIPS: Replace 'kernel_uses_smartmips_rixi' with 'cpu_has_rixi'. MIPS: Add base architecture support for RI and XI. MIPS: Optimise TLB handlers for MIPS32/64 R2 cores. MIPS: uasm: Add INS and EXT instructions. MIPS: Avoid pipeline stalls on some MIPS32R2 cores. MIPS: Make VPE count to be one-based. MIPS: Add new end of interrupt functionality for GIC. MIPS: Add EIC support for GIC. MIPS: Code clean-ups for the GIC. ...
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/Kconfig7
-rw-r--r--drivers/spi/Makefile1
-rw-r--r--drivers/spi/spi-octeon.c362
3 files changed, 370 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ecc31a1f73fc..8c2ff2490d99 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 22fd3a7251bc..c48df47e4b0f 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_SPI_MPC52xx) += spi-mpc52xx.o
obj-$(CONFIG_SPI_MXS) += spi-mxs.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");