2023-06-08 07:43:30

by Yinbo Zhu

[permalink] [raw]
Subject: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller

This bus driver supports the Loongson SPI hardware controller in the
Loongson platforms and supports to use DTS and PCI framework to
register SPI device resources.

Signed-off-by: Yinbo Zhu <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Mark Brown <[email protected]>
---
MAINTAINERS | 4 +
drivers/spi/Kconfig | 26 +++
drivers/spi/Makefile | 3 +
drivers/spi/spi-loongson-core.c | 275 ++++++++++++++++++++++++++++++++
drivers/spi/spi-loongson-pci.c | 55 +++++++
drivers/spi/spi-loongson-plat.c | 47 ++++++
drivers/spi/spi-loongson.h | 49 ++++++
7 files changed, 459 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 <[email protected]>
L: [email protected]
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 <[email protected]>
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..403b735bd0cf
--- /dev/null
+++ b/drivers/spi/spi-loongson-core.c
@@ -0,0 +1,275 @@
+// 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 val)
+{
+ int cs;
+ struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
+
+ cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG)
+ & ~(0x11 << spi_get_chipselect(spi, 0));
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG,
+ (val ? (0x11 << spi_get_chipselect(spi, 0)) :
+ (0x1 << spi_get_chipselect(spi, 0))) | 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);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, (val & ~3) |
+ loongson_spi->spcr);
+ val = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPER_REG);
+ loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPER_REG, (val & ~3) |
+ 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, 1);
+
+ 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 & 0x1) != LOONGSON_SPI_SPSR_RFEMPTY, 1, MSEC_PER_SEC);
+
+ 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 & ~1);
+
+ 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_CPOL | SPI_CPHA | 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 */
--
2.20.1



2023-06-08 10:32:34

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller

On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
>
> This bus driver supports the Loongson SPI hardware controller in the
> Loongson platforms and supports to use DTS and PCI framework to

the use

> register SPI device resources.

Thank you for an update. I have a few nit-picks below, but in general
this version is good (esp. if you address them)
Reviewed-by: Andy Shevchenko <[email protected]>

> Signed-off-by: Yinbo Zhu <[email protected]>
> Cc: Andy Shevchenko <[email protected]>
> Cc: Mark Brown <[email protected]>
> ---
> MAINTAINERS | 4 +
> drivers/spi/Kconfig | 26 +++
> drivers/spi/Makefile | 3 +
> drivers/spi/spi-loongson-core.c | 275 ++++++++++++++++++++++++++++++++
> drivers/spi/spi-loongson-pci.c | 55 +++++++
> drivers/spi/spi-loongson-plat.c | 47 ++++++
> drivers/spi/spi-loongson.h | 49 ++++++
> 7 files changed, 459 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 <[email protected]>
> L: [email protected]
> 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 <[email protected]>
> 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..403b735bd0cf
> --- /dev/null
> +++ b/drivers/spi/spi-loongson-core.c
> @@ -0,0 +1,275 @@
> +// 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 val)
> +{
> + int cs;
> + struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
> +
> + cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG)
> + & ~(0x11 << spi_get_chipselect(spi, 0));
> + loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG,
> + (val ? (0x11 << spi_get_chipselect(spi, 0)) :
> + (0x1 << spi_get_chipselect(spi, 0))) | cs);

Can be done as

static void loongson_spi_set_cs(struct spi_device *spi, bool en)

unsigned char mask = (BIT(4) | BIT(0)) << spi_get_chipselect(spi, 0);
unsigned char val = en ? mask : (BIT(0) << spi_get_chipselect(spi, 0));

cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG) & ~mask;
loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG, val | cs);

(Renamed variables to be consistent with the other uses in the driver below)

> +}
> +
> +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 & ~3) |
> + loongson_spi->spcr);

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 & ~3) |
> + loongson_spi->sper);

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, 1);
> +
> + 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);

+ Blank line

> + ret = readb_poll_timeout(loongson_spi->base + LOONGSON_SPI_SPSR_REG, loongson_spi->spsr,
> + (loongson_spi->spsr & 0x1) != LOONGSON_SPI_SPSR_RFEMPTY, 1, MSEC_PER_SEC);

(loongson_spi->spsr &
LOONGSON_SPI_SPSR_RFEMPTY) != LOONGSON_SPI_SPSR_RFEMPTY,
1, MSEC_PER_SEC);

> + 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;

> +

Unneeded blank line.

> + 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 & ~1);

BIT(0) ?
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_CPOL | SPI_CPHA | SPI_CS_HIGH;

... = 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 */
> --
> 2.20.1
>


--
With Best Regards,
Andy Shevchenko

2023-06-08 10:33:25

by Andy Shevchenko

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Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller

On Thu, Jun 8, 2023 at 1:15 PM Andy Shevchenko
<[email protected]> wrote:
> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:




> > + ret = readb_poll_timeout(loongson_spi->base + LOONGSON_SPI_SPSR_REG, loongson_spi->spsr,
> > + (loongson_spi->spsr & 0x1) != LOONGSON_SPI_SPSR_RFEMPTY, 1, MSEC_PER_SEC);
>
> (loongson_spi->spsr &
> LOONGSON_SPI_SPSR_RFEMPTY) != LOONGSON_SPI_SPSR_RFEMPTY,
> 1, MSEC_PER_SEC);

Actually the last should be USEC_PER_MSEC, as the parameter is in microseconds.

--
With Best Regards,
Andy Shevchenko

2023-06-08 10:43:22

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller

On Thu, Jun 08, 2023 at 01:15:39PM +0300, Andy Shevchenko wrote:
> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
> >
> > This bus driver supports the Loongson SPI hardware controller in the
> > Loongson platforms and supports to use DTS and PCI framework to

Please delete unneeded context from mails when replying. Doing this
makes it much easier to find your reply in the message, helping ensure
it won't be missed by people scrolling through the irrelevant quoted
material.


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2023-06-08 12:15:18

by Mark Brown

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Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller

On Thu, Jun 08, 2023 at 07:45:49PM +0800, zhuyinbo wrote:
> 在 2023/6/8 下午6:29, Mark Brown 写道:
> > On Thu, Jun 08, 2023 at 01:15:39PM +0300, Andy Shevchenko wrote:
> > > On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:

> > > > This bus driver supports the Loongson SPI hardware controller in the
> > > > Loongson platforms and supports to use DTS and PCI framework to

> > Please delete unneeded context from mails when replying. Doing this
> > makes it much easier to find your reply in the message, helping ensure
> > it won't be missed by people scrolling through the irrelevant quoted
> > material.

> okay, I got it.

That was more directed at Andy than you!


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2023-06-08 12:30:46

by Yinbo Zhu

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Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller



在 2023/6/8 下午6:29, Mark Brown 写道:
> On Thu, Jun 08, 2023 at 01:15:39PM +0300, Andy Shevchenko wrote:
>> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
>>>
>>> This bus driver supports the Loongson SPI hardware controller in the
>>> Loongson platforms and supports to use DTS and PCI framework to
>
> Please delete unneeded context from mails when replying. Doing this
> makes it much easier to find your reply in the message, helping ensure
> it won't be missed by people scrolling through the irrelevant quoted
> material.


okay, I got it.

Thanks,
Yinbo


2023-06-09 03:34:13

by Yinbo Zhu

[permalink] [raw]
Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller



在 2023/6/8 下午7:53, Mark Brown 写道:
> On Thu, Jun 08, 2023 at 07:45:49PM +0800, zhuyinbo wrote:
>> 在 2023/6/8 下午6:29, Mark Brown 写道:
>>> On Thu, Jun 08, 2023 at 01:15:39PM +0300, Andy Shevchenko wrote:
>>>> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
>
>>>>> This bus driver supports the Loongson SPI hardware controller in the
>>>>> Loongson platforms and supports to use DTS and PCI framework to
>
>>> Please delete unneeded context from mails when replying. Doing this
>>> makes it much easier to find your reply in the message, helping ensure
>>> it won't be missed by people scrolling through the irrelevant quoted
>>> material.
>
>> okay, I got it.
>
> That was more directed at Andy than you!


Okay, I will learn from Andy.

Thanks
>


2023-06-09 07:22:50

by Yinbo Zhu

[permalink] [raw]
Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller



在 2023/6/8 下午6:15, Andy Shevchenko 写道:
> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
>>
>> This bus driver supports the Loongson SPI hardware controller in the
>> Loongson platforms and supports to use DTS and PCI framework to
>
> the use


okay, I got it.

>
>> register SPI device resources.
>
> Thank you for an update. I have a few nit-picks below, but in general
> this version is good (esp. if you address them)
> Reviewed-by: Andy Shevchenko <[email protected]>
>


You're welcome, I will add the reviewed-by in v13.

...

>> +static void loongson_spi_set_cs(struct spi_device *spi, bool val)
>> +{
>> + int cs;
>> + struct loongson_spi *loongson_spi = spi_controller_get_devdata(spi->controller);
>> +
>> + cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG)
>> + & ~(0x11 << spi_get_chipselect(spi, 0));
>> + loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG,
>> + (val ? (0x11 << spi_get_chipselect(spi, 0)) :
>> + (0x1 << spi_get_chipselect(spi, 0))) | cs);
>
> Can be done as
>
> static void loongson_spi_set_cs(struct spi_device *spi, bool en)
>
> unsigned char mask = (BIT(4) | BIT(0)) << spi_get_chipselect(spi, 0);
> unsigned char val = en ? mask : (BIT(0) << spi_get_chipselect(spi, 0));
>
> cs = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SFCS_REG) & ~mask;
> loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SFCS_REG, val | cs);


okay, I will do it.

>
> (Renamed variables to be consistent with the other uses in the driver below)


sorry, I don't got it. Are you referring to the following changes ?
loongson_spi_set_cs(spi, 1) => loongson_spi_set_cs(spi, true)

>
>> +}
>> +
>> +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);


This seems to be "val &= ~GENMASK(1, 0);"

>
>> + loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, (val & ~3) |
>> + loongson_spi->spcr);
>
> loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPCR_REG, val
> | loongson_spi->spcr);


okay, I got it.

>
>> + val = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_SPER_REG);
>
> val &= GENMASK(1, 0);


This seems to be "val &= ~GENMASK(1, 0);"

>
>> + loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPER_REG, (val & ~3) |
>> + loongson_spi->sper);
>
> loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_SPER_REG, val
> | loongson_spi->sper);
>


okay, I got it.

>> + 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, 1);
>> +
>> + 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);
>
> + Blank line


okay, I will add the blank line.

>
>> + ret = readb_poll_timeout(loongson_spi->base + LOONGSON_SPI_SPSR_REG, loongson_spi->spsr,
>> + (loongson_spi->spsr & 0x1) != LOONGSON_SPI_SPSR_RFEMPTY, 1, MSEC_PER_SEC);
>
> (loongson_spi->spsr &
> LOONGSON_SPI_SPSR_RFEMPTY) != LOONGSON_SPI_SPSR_RFEMPTY,
> 1, MSEC_PER_SEC);


okay, I got it.

>
>> + 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;
>
>> +
>
> Unneeded blank line.


okay, I will remove the blank line.

>
>> + 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 & ~1);
>
> BIT(0) ?
> LOONGSON_SPI_PARA_MEM_EN ?


I will use LOONGSON_SPI_PARA_MEM_EN.

>
>> + return 0;
>> +}
>> +

...

>> +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_CPOL | SPI_CPHA | SPI_CS_HIGH;
>
> ... = SPI_MODE_X_MASK | SPI_CS_HIGH;


okay, I got it.


Thanks,
Yinbo


2023-06-09 07:24:13

by Yinbo Zhu

[permalink] [raw]
Subject: Re: [PATCH v12 2/2] spi: loongson: add bus driver for the loongson spi controller



在 2023/6/8 下午6:18, Andy Shevchenko 写道:
> On Thu, Jun 8, 2023 at 1:15 PM Andy Shevchenko
> <[email protected]> wrote:
>> On Thu, Jun 8, 2023 at 10:28 AM Yinbo Zhu <[email protected]> wrote:
>>> + ret = readb_poll_timeout(loongson_spi->base + LOONGSON_SPI_SPSR_REG, loongson_spi->spsr,
>>> + (loongson_spi->spsr & 0x1) != LOONGSON_SPI_SPSR_RFEMPTY, 1, MSEC_PER_SEC);
>>
>> (loongson_spi->spsr &
>> LOONGSON_SPI_SPSR_RFEMPTY) != LOONGSON_SPI_SPSR_RFEMPTY,
>> 1, MSEC_PER_SEC);
>
> Actually the last should be USEC_PER_MSEC, as the parameter is in microseconds.


okay, I got it.

Thanks
>