[PATCH v2] spi: octeon: Add thunderx driver

From: Jan Glauber
Date: Mon Jul 25 2016 - 13:56:51 EST


Add ThunderX SPI driver using the shared part from the Octeon
driver. The main difference of the ThunderX driver is that it
is a PCI device so probing is different. The system clock settings
can be specified in device tree.

Signed-off-by: Jan Glauber <jglauber@xxxxxxxxxx>
---
drivers/spi/Kconfig | 7 ++
drivers/spi/Makefile | 2 +
drivers/spi/spi-cavium-thunderx.c | 140 ++++++++++++++++++++++++++++++++++++++
drivers/spi/spi-cavium.h | 3 +
4 files changed, 152 insertions(+)
create mode 100644 drivers/spi/spi-cavium-thunderx.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 4b931ec..e0ee112 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -630,6 +630,13 @@ config SPI_TEGRA20_SLINK
help
SPI driver for Nvidia Tegra20/Tegra30 SLINK Controller interface.

+config SPI_THUNDERX
+ tristate "Cavium ThunderX SPI controller"
+ depends on (ARM64 || CONFIG_TEST) && 64BIT && PCI
+ help
+ SPI host driver for the hardware found on Cavium ThunderX
+ SOCs.
+
config SPI_TOPCLIFF_PCH
tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) SPI"
depends on PCI && (X86_32 || MIPS || COMPILE_TEST)
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 185367e..133364b 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -91,6 +91,8 @@ obj-$(CONFIG_SPI_TEGRA114) += spi-tegra114.o
obj-$(CONFIG_SPI_TEGRA20_SFLASH) += spi-tegra20-sflash.o
obj-$(CONFIG_SPI_TEGRA20_SLINK) += spi-tegra20-slink.o
obj-$(CONFIG_SPI_TLE62X0) += spi-tle62x0.o
+spi-thunderx-objs := spi-cavium.o spi-cavium-thunderx.o
+obj-$(CONFIG_SPI_THUNDERX) += spi-thunderx.o
obj-$(CONFIG_SPI_TOPCLIFF_PCH) += spi-topcliff-pch.o
obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
diff --git a/drivers/spi/spi-cavium-thunderx.c b/drivers/spi/spi-cavium-thunderx.c
new file mode 100644
index 0000000..28c3dcc
--- /dev/null
+++ b/drivers/spi/spi-cavium-thunderx.c
@@ -0,0 +1,140 @@
+/*
+ * Cavium ThunderX SPI driver.
+ *
+ * Copyright (C) 2016 Cavium Inc.
+ * Authors: Jan Glauber <jglauber@xxxxxxxxxx>
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/spi/spi.h>
+
+#include "spi-cavium.h"
+
+#define DRV_NAME "spi-thunderx"
+
+#define SYS_FREQ_DEFAULT 700000000 /* 700 Mhz */
+
+static int thunderx_spi_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ struct device *dev = &pdev->dev;
+ struct spi_master *master;
+ struct octeon_spi *p;
+ int ret = -ENOENT;
+
+ master = spi_alloc_master(dev, sizeof(struct octeon_spi));
+ if (!master)
+ return -ENOMEM;
+ p = spi_master_get_devdata(master);
+
+ ret = pci_enable_device(pdev);
+ if (ret) {
+ dev_err(dev, "Failed to enable PCI device\n");
+ goto out_free;
+ }
+
+ ret = pci_request_regions(pdev, DRV_NAME);
+ if (ret) {
+ dev_err(dev, "PCI request regions failed 0x%x\n", ret);
+ goto out_disable;
+ }
+
+ p->register_base = pci_ioremap_bar(pdev, 0);
+ if (!p->register_base) {
+ dev_err(dev, "Cannot map reg base\n");
+ ret = -EINVAL;
+ goto out_region;
+ }
+
+ p->regs.config = 0x1000;
+ p->regs.status = 0x1008;
+ p->regs.tx = 0x1010;
+ p->regs.data = 0x1080;
+
+ p->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(p->clk))
+ goto out_unmap;
+
+ ret = clk_prepare_enable(p->clk);
+ if (ret)
+ goto out_clock_devm;
+
+ p->sys_freq = clk_get_rate(p->clk);
+ if (!p->sys_freq)
+ p->sys_freq = SYS_FREQ_DEFAULT;
+ dev_info(dev, "Set system clock to %u\n", p->sys_freq);
+
+ master->num_chipselect = 4;
+ master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH |
+ SPI_LSB_FIRST | SPI_3WIRE;
+ master->transfer_one_message = octeon_spi_transfer_one_message;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
+ master->dev.of_node = pdev->dev.of_node;
+
+ pci_set_drvdata(pdev, master);
+ ret = devm_spi_register_master(dev, master);
+ if (ret) {
+ dev_err(&pdev->dev, "Register master failed: %d\n", ret);
+ goto out_clock;
+ }
+
+ return 0;
+
+out_clock:
+ clk_disable_unprepare(p->clk);
+out_clock_devm:
+ devm_clk_put(dev, p->clk);
+out_unmap:
+ iounmap(p->register_base);
+out_region:
+ pci_release_regions(pdev);
+out_disable:
+ pci_disable_device(pdev);
+out_free:
+ spi_master_put(master);
+ return ret;
+}
+
+static void thunderx_spi_remove(struct pci_dev *pdev)
+{
+ struct spi_master *master = pci_get_drvdata(pdev);
+ struct octeon_spi *p;
+
+ p = spi_master_get_devdata(master);
+ if (!p)
+ return;
+
+ /* Put everything in a known state. */
+ writeq(0, p->register_base + OCTEON_SPI_CFG(p));
+
+ clk_disable_unprepare(p->clk);
+ devm_clk_put(&pdev->dev, p->clk);
+ iounmap(p->register_base);
+ pci_release_regions(pdev);
+ pci_disable_device(pdev);
+ pci_set_drvdata(pdev, NULL);
+}
+
+static const struct pci_device_id thunderx_spi_pci_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa00b) },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, thunderx_spi_pci_id_table);
+
+static struct pci_driver thunderx_spi_driver = {
+ .name = DRV_NAME,
+ .id_table = thunderx_spi_pci_id_table,
+ .probe = thunderx_spi_probe,
+ .remove = thunderx_spi_remove,
+};
+
+module_pci_driver(thunderx_spi_driver);
+
+MODULE_DESCRIPTION("Cavium, Inc. ThunderX SPI bus driver");
+MODULE_AUTHOR("Jan Glauber");
+MODULE_LICENSE("GPL");
diff --git a/drivers/spi/spi-cavium.h b/drivers/spi/spi-cavium.h
index 88c5f36..1f91d61 100644
--- a/drivers/spi/spi-cavium.h
+++ b/drivers/spi/spi-cavium.h
@@ -1,6 +1,8 @@
#ifndef __SPI_CAVIUM_H
#define __SPI_CAVIUM_H

+#include <linux/clk.h>
+
#define OCTEON_SPI_MAX_BYTES 9
#define OCTEON_SPI_MAX_CLOCK_HZ 16000000

@@ -17,6 +19,7 @@ struct octeon_spi {
u64 cs_enax;
int sys_freq;
struct octeon_spi_regs regs;
+ struct clk *clk;
};

#define OCTEON_SPI_CFG(x) (x->regs.config)
--
2.9.0.rc0.21.g7777322