This bus driver supports the Loongson SPI hardware controller in the
Loongson platforms and supports the use DTS and PCI framework to
register SPI device resources.
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
---
MAINTAINERS | 4 +
drivers/spi/Kconfig | 26 +++
drivers/spi/Makefile | 3 +
drivers/spi/spi-loongson-core.c | 279 ++++++++++++++++++++++++++++++++
drivers/spi/spi-loongson-pci.c | 55 +++++++
drivers/spi/spi-loongson-plat.c | 47 ++++++
drivers/spi/spi-loongson.h | 49 ++++++
7 files changed, 463 insertions(+)
create mode 100644 drivers/spi/spi-loongson-core.c
create mode 100644 drivers/spi/spi-loongson-pci.c
create mode 100644 drivers/spi/spi-loongson-plat.c
create mode 100644 drivers/spi/spi-loongson.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 5e604dddd87b..69cb8fb2a0e1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12191,6 +12191,10 @@ M: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
L: linux-spi@xxxxxxxxxxxxxxx
S: Maintained
F: Documentation/devicetree/bindings/spi/loongson,ls2k-spi.yaml
+F: drivers/spi/spi-loongson-core.c
+F: drivers/spi/spi-loongson-pci.c
+F: drivers/spi/spi-loongson-plat.c
+F: drivers/spi/spi-loongson.h
LOONGSON-2 SOC SERIES GUTS DRIVER
M: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 3de2ebe8294a..6b953904792e 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -516,6 +516,32 @@ config SPI_LM70_LLP
which interfaces to an LM70 temperature sensor using
a parallel port.
+config SPI_LOONGSON_CORE
+ tristate
+ depends on LOONGARCH || COMPILE_TEST
+
+config SPI_LOONGSON_PCI
+ tristate "Loongson SPI Controller PCI Driver Support"
+ select SPI_LOONGSON_CORE
+ depends on PCI && (LOONGARCH || COMPILE_TEST)
+ help
+ This bus driver supports the Loongson SPI hardware controller in
+ the Loongson platforms and supports to use PCI framework to
+ register SPI device resources.
+ Say Y or M here if you want to use the SPI controller on
+ Loongson platform.
+
+config SPI_LOONGSON_PLATFORM
+ tristate "Loongson SPI Controller Platform Driver Support"
+ select SPI_LOONGSON_CORE
+ depends on OF && (LOONGARCH || COMPILE_TEST)
+ help
+ This bus driver supports the Loongson SPI hardware controller in
+ the Loongson platforms and supports to use DTS framework to
+ register SPI device resources.
+ Say Y or M here if you want to use the SPI controller on
+ Loongson platform.
+
config SPI_LP8841_RTC
tristate "ICP DAS LP-8841 SPI Controller for RTC"
depends on MACH_PXA27X_DT || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 28c4817a8a74..3e933064d237 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -71,6 +71,9 @@ obj-$(CONFIG_SPI_INTEL_PLATFORM) += spi-intel-platform.o
obj-$(CONFIG_SPI_LANTIQ_SSC) += spi-lantiq-ssc.o
obj-$(CONFIG_SPI_JCORE) += spi-jcore.o
obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o
+obj-$(CONFIG_SPI_LOONGSON_CORE) += spi-loongson-core.o
+obj-$(CONFIG_SPI_LOONGSON_PCI) += spi-loongson-pci.o
+obj-$(CONFIG_SPI_LOONGSON_PLATFORM) += spi-loongson-plat.o
obj-$(CONFIG_SPI_LP8841_RTC) += spi-lp8841-rtc.o
obj-$(CONFIG_SPI_MESON_SPICC) += spi-meson-spicc.o
obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o
diff --git a/drivers/spi/spi-loongson-core.c b/drivers/spi/spi-loongson-core.c
new file mode 100644
index 000000000000..f97800b6fd65
--- /dev/null
+++ b/drivers/spi/spi-loongson-core.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Loongson SPI Support
+// Copyright (C) 2023 Loongson Technology Corporation Limited
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include "spi-loongson.h"
+
+static inline void loongson_spi_write_reg(struct loongson_spi *spi, unsigned char reg,
+ unsigned char data)
+{
+ writeb(data, spi->base + reg);
+}
+
+static inline char loongson_spi_read_reg(struct loongson_spi *spi, unsigned char reg)
+{
+ return readb(spi->base + reg);
+}
+
+static void loongson_spi_set_cs(struct spi_device *spi, bool en)
+{
+ int cs;
+ unsigned char mask = (BIT(4) | BIT(0)) << spi_get_chipselect(spi, 0);
+ unsigned char val = en ? mask : (BIT(0) << spi_get_chipselect(spi, 0));
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
+
+ cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG) & ~mask;
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG, val | cs);
+}
+
+static void loongson_spi_set_clk(struct loongson_spi *loongson_spi, unsigned int hz)
+{
+ unsigned char val;
+ unsigned int div, div_tmp;
+ static const char rdiv[12] = {0, 1, 4, 2, 3, 5, 6, 7, 8, 9, 10, 11};
+
+ div = clamp_val(DIV_ROUND_UP_ULL(loongson_spi->clk_rate, hz), 2, 4096);
+ div_tmp = rdiv[fls(div - 1)];
+ loongson_spi->spcr = (div_tmp & GENMASK(1, 0)) >> 0;
+ loongson_spi->sper = (div_tmp & GENMASK(3, 2)) >> 2;
+ val = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPCR_REG);
+ val &= ~GENMASK(1, 0);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, val |
+ loongson_spi->spcr);
+ val = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPER_REG);
+ val &= ~GENMASK(1, 0);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPER_REG, val |
+ loongson_spi->sper);
+ loongson_spi->hz = hz;
+}
+
+static void loongson_spi_set_mode(struct loongson_spi *loongson_spi,
+ struct spi_device *spi)
+{
+ unsigned char val;
+
+ val = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPCR_REG);
+ val &= ~(LOONGSON_SPI_SPCR_CPOL | LOONGSON_SPI_SPCR_CPHA);
+ if (spi->mode & SPI_CPOL)
+ val |= LOONGSON_SPI_SPCR_CPOL;
+ if (spi->mode & SPI_CPHA)
+ val |= LOONGSON_SPI_SPCR_CPHA;
+
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, val);
+ loongson_spi->mode |= spi->mode;
+}
+
+static int loongson_spi_update_state(struct loongson_spi *loongson_spi,
+ struct spi_device *spi, struct spi_transfer *t)
+{
+ if (t && loongson_spi->hz != t->speed_hz)
+ loongson_spi_set_clk(loongson_spi, t->speed_hz);
+
+ if ((spi->mode ^ loongson_spi->mode) & SPI_MODE_X_MASK)
+ loongson_spi_set_mode(loongson_spi, spi);
+
+ return 0;
+}
+
+static int loongson_spi_setup(struct spi_device *spi)
+{
+ struct loongson_spi *loongson_spi;
+
+ loongson_spi = spi_controller_get_devdata(spi->controller);
+ if (spi->bits_per_word % 8)
+ return -EINVAL;
+
+ if (spi_get_chipselect(spi, 0) >= spi->controller->num_chipselect)
+ return -EINVAL;
+
+ loongson_spi->hz = 0;
+ loongson_spi_set_cs(spi, true);
+
+ return 0;
+}
+
+static int loongson_spi_write_read_8bit(struct spi_device *spi, const u8 **tx_buf,
+ u8 **rx_buf, unsigned int num)
+{
+ int ret;
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
+
+ if (tx_buf && *tx_buf)
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_FIFO_REG, *((*tx_buf)++));
+ else
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_FIFO_REG, 0);
+
+ ret = readb_poll_timeout(loongson_spi->base + LOONGSON_SPI_SPSR_REG,
+ loongson_spi->spsr, (loongson_spi->spsr &
+ LOONGSON_SPI_SPSR_RFEMPTY) != LOONGSON_SPI_SPSR_RFEMPTY,
+ 1, USEC_PER_MSEC);
+
+ if (rx_buf && *rx_buf)
+ *(*rx_buf)++ = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_FIFO_REG);
+ else
+ loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_FIFO_REG);
+
+ return ret;
+}
+
+static int loongson_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
+{
+ int ret;
+ unsigned int count;
+ const u8 *tx = xfer->tx_buf;
+ u8 *rx = xfer->rx_buf;
+
+ count = xfer->len;
+ do {
+ ret = loongson_spi_write_read_8bit(spi, &tx, &rx, count);
+ if (ret)
+ break;
+ } while (--count);
+
+ return ret;
+}
+
+static int loongson_spi_prepare_message(struct spi_controller *ctlr, struct spi_message *m)
+{
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(ctlr);
+
+ loongson_spi->para = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_PARA_REG);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_PARA_REG, loongson_spi->para &
+ ~LOONGSON_SPI_PARA_MEM_EN);
+
+ return 0;
+}
+
+static int loongson_spi_transfer_one(struct spi_controller *ctrl, struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
+
+ loongson_spi_update_state(loongson_spi, spi, xfer);
+ if (xfer->len)
+ return loongson_spi_write_read(spi, xfer);
+
+ return 0;
+}
+
+static int loongson_spi_unprepare_message(struct spi_controller *ctrl, struct spi_message *m)
+{
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(ctrl);
+
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_PARA_REG, loongson_spi->para);
+
+ return 0;
+}
+
+static void loongson_spi_reginit(struct loongson_spi *loongson_spi_dev)
+{
+ unsigned char val;
+
+ val = loongson_spi_read_reg(loongson_spi_dev, LOONGSON_SPI_SPCR_REG);
+ val &= ~LOONGSON_SPI_SPCR_SPE;
+ loongson_spi_write_reg(loongson_spi_dev, LOONGSON_SPI_SPCR_REG, val);
+
+ loongson_spi_write_reg(loongson_spi_dev, LOONGSON_SPI_SPSR_REG,
+ (LOONGSON_SPI_SPSR_SPIF | LOONGSON_SPI_SPSR_WCOL));
+
+ val = loongson_spi_read_reg(loongson_spi_dev, LOONGSON_SPI_SPCR_REG);
+ val |= LOONGSON_SPI_SPCR_SPE;
+ loongson_spi_write_reg(loongson_spi_dev, LOONGSON_SPI_SPCR_REG, val);
+}
+
+int loongson_spi_init_controller(struct device *dev, void __iomem *regs)
+{
+ struct spi_controller *controller;
+ struct loongson_spi *spi;
+ struct clk *clk;
+
+ controller = devm_spi_alloc_host(dev, sizeof(struct loongson_spi));
+ if (controller == NULL)
+ return -ENOMEM;
+
+ controller->mode_bits = SPI_MODE_X_MASK | SPI_CS_HIGH;
+ controller->setup = loongson_spi_setup;
+ controller->prepare_message = loongson_spi_prepare_message;
+ controller->transfer_one = loongson_spi_transfer_one;
+ controller->unprepare_message = loongson_spi_unprepare_message;
+ controller->set_cs = loongson_spi_set_cs;
+ controller->num_chipselect = 4;
+ device_set_node(&controller->dev, dev_fwnode(dev));
+ dev_set_drvdata(dev, controller);
+
+ spi = spi_controller_get_devdata(controller);
+ spi->base = regs;
+ spi->controller = controller;
+
+ clk = devm_clk_get_optional(dev, NULL);
+ if (IS_ERR(clk))
+ return dev_err_probe(dev, PTR_ERR(clk), "unable to get clock\n");
+
+ spi->clk_rate = clk_get_rate(clk);
+ loongson_spi_reginit(spi);
+
+ spi->mode = 0;
+
+ return devm_spi_register_controller(dev, controller);
+}
+EXPORT_SYMBOL_NS_GPL(loongson_spi_init_controller, SPI_LOONGSON_CORE);
+
+static int __maybe_unused loongson_spi_suspend(struct device *dev)
+{
+ struct loongson_spi *loongson_spi;
+ struct spi_controller *controller;
+
+ controller = dev_get_drvdata(dev);
+ spi_controller_suspend(controller);
+
+ loongson_spi = spi_controller_get_devdata(controller);
+
+ loongson_spi->spcr = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPCR_REG);
+ loongson_spi->sper = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPER_REG);
+ loongson_spi->spsr = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPSR_REG);
+ loongson_spi->para = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_PARA_REG);
+ loongson_spi->sfcs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG);
+ loongson_spi->timi = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_TIMI_REG);
+
+ return 0;
+}
+
+static int __maybe_unused loongson_spi_resume(struct device *dev)
+{
+ struct loongson_spi *loongson_spi;
+ struct spi_controller *controller;
+
+ controller = dev_get_drvdata(dev);
+ loongson_spi = spi_controller_get_devdata(controller);
+
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, loongson_spi->spcr);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPER_REG, loongson_spi->sper);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPSR_REG, loongson_spi->spsr);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_PARA_REG, loongson_spi->para);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG, loongson_spi->sfcs);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_TIMI_REG, loongson_spi->timi);
+
+ spi_controller_resume(controller);
+
+ return 0;
+}
+
+const struct dev_pm_ops loongson_spi_dev_pm_ops = {
+ .suspend = loongson_spi_suspend,
+ .resume = loongson_spi_resume,
+};
+EXPORT_SYMBOL_NS_GPL(loongson_spi_dev_pm_ops, SPI_LOONGSON_CORE);
+
+MODULE_DESCRIPTION("Loongson SPI core driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/spi/spi-loongson-pci.c b/drivers/spi/spi-loongson-pci.c
new file mode 100644
index 000000000000..134cda0c13a5
--- /dev/null
+++ b/drivers/spi/spi-loongson-pci.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0+
+// PCI interface driver for Loongson SPI Support
+// Copyright (C) 2023 Loongson Technology Corporation Limited
+
+#include <linux/mod_devicetable.h>
+#include <linux/pci.h>
+
+#include "spi-loongson.h"
+
+static int loongson_spi_pci_register(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int ret;
+ void __iomem *reg_base;
+ struct device *dev = &pdev->dev;
+ int pci_bar = 0;
+
+ ret = pcim_enable_device(pdev);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "cannot enable pci device\n");
+
+ ret = pcim_iomap_regions(pdev, BIT(pci_bar), pci_name(pdev));
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to request and remap memory\n");
+
+ reg_base = pcim_iomap_table(pdev)[pci_bar];
+
+ ret = loongson_spi_init_controller(dev, reg_base);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to initialize controller\n");
+
+ return 0;
+}
+
+static struct pci_device_id loongson_spi_devices[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a0b) },
+ { PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a1b) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, loongson_spi_devices);
+
+static struct pci_driver loongson_spi_pci_driver = {
+ .name = "loongson-spi-pci",
+ .id_table = loongson_spi_devices,
+ .probe = loongson_spi_pci_register,
+ .driver = {
+ .bus = &pci_bus_type,
+ .pm = &loongson_spi_dev_pm_ops,
+ },
+};
+module_pci_driver(loongson_spi_pci_driver);
+
+MODULE_DESCRIPTION("Loongson spi pci driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(SPI_LOONGSON_CORE);
diff --git a/drivers/spi/spi-loongson-plat.c b/drivers/spi/spi-loongson-plat.c
new file mode 100644
index 000000000000..c066e5f5891e
--- /dev/null
+++ b/drivers/spi/spi-loongson-plat.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Platform driver for Loongson SPI Support
+// Copyright (C) 2023 Loongson Technology Corporation Limited
+
+#include <linux/err.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+
+#include "spi-loongson.h"
+
+static int loongson_spi_platform_probe(struct platform_device *pdev)
+{
+ int ret;
+ void __iomem *reg_base;
+ struct device *dev = &pdev->dev;
+
+ reg_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(reg_base))
+ return PTR_ERR(reg_base);
+
+ ret = loongson_spi_init_controller(dev, reg_base);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to initialize controller\n");
+
+ return 0;
+}
+
+static const struct of_device_id loongson_spi_id_table[] = {
+ { .compatible = "loongson,ls2k1000-spi" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, loongson_spi_id_table);
+
+static struct platform_driver loongson_spi_plat_driver = {
+ .probe = loongson_spi_platform_probe,
+ .driver = {
+ .name = "loongson-spi",
+ .bus = &platform_bus_type,
+ .pm = &loongson_spi_dev_pm_ops,
+ .of_match_table = loongson_spi_id_table,
+ },
+};
+module_platform_driver(loongson_spi_plat_driver);
+
+MODULE_DESCRIPTION("Loongson spi platform driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(SPI_LOONGSON_CORE);
diff --git a/drivers/spi/spi-loongson.h b/drivers/spi/spi-loongson.h
new file mode 100644
index 000000000000..35f95b161842
--- /dev/null
+++ b/drivers/spi/spi-loongson.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/* Header File for Loongson SPI Driver. */
+/* Copyright (C) 2023 Loongson Technology Corporation Limited */
+
+#ifndef __LINUX_SPI_LOONGSON_H
+#define __LINUX_SPI_LOONGSON_H
+
+#include <linux/bits.h>
+#include <linux/pm.h>
+#include <linux/types.h>
+
+#define LOONGSON_SPI_SPCR_REG 0x00
+#define LOONGSON_SPI_SPSR_REG 0x01
+#define LOONGSON_SPI_FIFO_REG 0x02
+#define LOONGSON_SPI_SPER_REG 0x03
+#define LOONGSON_SPI_PARA_REG 0x04
+#define LOONGSON_SPI_SFCS_REG 0x05
+#define LOONGSON_SPI_TIMI_REG 0x06
+
+/* Bits definition for Loongson SPI register */
+#define LOONGSON_SPI_PARA_MEM_EN BIT(0)
+#define LOONGSON_SPI_SPCR_CPHA BIT(2)
+#define LOONGSON_SPI_SPCR_CPOL BIT(3)
+#define LOONGSON_SPI_SPCR_SPE BIT(6)
+#define LOONGSON_SPI_SPSR_RFEMPTY BIT(0)
+#define LOONGSON_SPI_SPSR_WCOL BIT(6)
+#define LOONGSON_SPI_SPSR_SPIF BIT(7)
+
+struct device;
+struct spi_controller;
+
+struct loongson_spi {
+ struct spi_controller *controller;
+ void __iomem *base;
+ int cs_active;
+ unsigned int hz;
+ unsigned char spcr;
+ unsigned char sper;
+ unsigned char spsr;
+ unsigned char para;
+ unsigned char sfcs;
+ unsigned char timi;
+ unsigned int mode;
+ u64 clk_rate;
+};
+
+int loongson_spi_init_controller(struct device *dev, void __iomem *reg);
+extern const struct dev_pm_ops loongson_spi_dev_pm_ops;
+#endif /* __LINUX_SPI_LOONGSON_H */
