| Message ID | 1608973923-8328-1-git-send-email-zhangqing@loongson.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v5,1/4] spi: LS7A: Add Loongson LS7A SPI controller driver support | expand |
Hi, Qing, On Sat, Dec 26, 2020 at 5:13 PM Qing Zhang <zhangqing@loongson.cn> wrote: > > The SPI controller has the following characteristics: > > - Full-duplex synchronous serial data transmission > - Support up to 4 variable length byte transmission > - Main mode support > - Mode failure generates an error flag and issues an interrupt request > - Double buffer receiver > - Serial clock with programmable polarity and phase > - SPI can be controlled in wait mode > - Support boot from SPI > > Use mtd_debug tool to earse/write/read /dev/mtd0 on development. > > eg: > > [root@linux mtd-utils-1.0.0]# mtd_debug erase /dev/mtd0 0x20000 0x40000 > Erased 262144 bytes from address 0x00020000 in flash > [root@linux mtd-utils-1.0.0]# mtd_debug write /dev/mtd0 0x20000 13 1.img > Copied 13 bytes from 1.img to address 0x00020000 in flash > [root@linux mtd-utils-1.0.0]# mtd_debug read /dev/mtd0 0x20000 13 2.img > Copied 13 bytes from address 0x00020000 in flash to 2.img > [root@linux mtd-utils-1.0.0]# cmp -l 1.img 2.img > > Signed-off-by: Qing Zhang <zhangqing@loongson.cn> > --- > > v2: > - keep Kconfig and Makefile sorted > - make the entire comment a C++ one so things look more intentional > - Fix unclear indentation > - make conditional statements to improve legibility > - Don't use static inline > - the core handle message queue > - Add a new binding document > - Fix probe part mixed pdev and PCI > > v3: > - expose set_cs to the core and let it handle things > - replace transfer_one_message to transfer_one > - replace spi_alloc_master to devm_spi_alloc_master > - split out into prepare/unprepare_message > - releases pci regions before unregister master > > v4: > - names used in the manual > - rename ls7a_spi_do_transfer to ls7a_spi_setup_transfer > - change read the spcr and sper outside of this function > - mode configuration moved to prepare instead > - remove redundancy code about unprepare/prepare_message > - used 0x4 instead of 0x1,WFEMPTY instead of RFEMPTY > > v5: > - remove unnecessary blank lines > > --- > drivers/spi/Kconfig | 7 ++ > drivers/spi/Makefile | 1 + > drivers/spi/spi-ls7a.c | 280 +++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 288 insertions(+) > create mode 100644 drivers/spi/spi-ls7a.c > > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig > index aadaea0..af7c0d4 100644 > --- a/drivers/spi/Kconfig > +++ b/drivers/spi/Kconfig > @@ -413,6 +413,13 @@ config SPI_LP8841_RTC > Say N here unless you plan to run the kernel on an ICP DAS > LP-8x4x industrial computer. > > +config SPI_LS7A > + tristate "Loongson LS7A SPI Controller Support" > + depends on CPU_LOONGSON64 || COMPILE_TEST > + help > + This drivers supports the Loongson LS7A SPI controller in master > + SPI mode. > + > config SPI_MPC52xx > tristate "Freescale MPC52xx SPI (non-PSC) controller support" > depends on PPC_MPC52xx > diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile > index 6fea582..d015cf2 100644 > --- a/drivers/spi/Makefile > +++ b/drivers/spi/Makefile > @@ -61,6 +61,7 @@ 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_LP8841_RTC) += spi-lp8841-rtc.o > +obj-$(CONFIG_SPI_LS7A) += spi-ls7a.o > obj-$(CONFIG_SPI_MESON_SPICC) += spi-meson-spicc.o > obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o > obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o > diff --git a/drivers/spi/spi-ls7a.c b/drivers/spi/spi-ls7a.c > new file mode 100644 > index 0000000..d24b6d91 > --- /dev/null > +++ b/drivers/spi/spi-ls7a.c > @@ -0,0 +1,280 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// > +// Loongson LS7A SPI Controller driver > +// > +// Copyright (C) 2020 Loongson Technology Corporation Limited. > +// > + > +#include <linux/module.h> > +#include <linux/pci.h> > +#include <linux/spi/spi.h> > + > +/* define spi register */ > +#define SPCR 0x00 > +#define SPSR 0x01 > +#define FIFO 0x02 > +#define SPER 0x03 > +#define SFC_PARAM 0x04 > +#define SFC_SOFTCS 0x05 > +#define SFC_TIMING 0x06 > + > +struct ls7a_spi { > + struct spi_master *master; > + void __iomem *base; > + unsigned int hz; > + unsigned int mode; > +}; > + > +static void ls7a_spi_write_reg(struct ls7a_spi *spi, > + unsigned char reg, > + unsigned char data) > +{ > + writeb(data, spi->base + reg); > +} > + > +static char ls7a_spi_read_reg(struct ls7a_spi *spi, unsigned char reg) > +{ > + return readb(spi->base + reg); > +} > + > +static int ls7a_spi_prepare_message(struct spi_master *master, > + struct spi_message *msg) > +{ > + struct ls7a_spi *ls7a_spi; > + struct spi_device *spi = msg->spi; > + unsigned char val; > + > + ls7a_spi = spi_master_get_devdata(master); > + > + if (ls7a_spi->mode != spi->mode) { > + val = ls7a_spi_read_reg(ls7a_spi, SPCR); > + val &= ~0xc; > + if (spi->mode & SPI_CPOL) > + val |= 8; > + if (spi->mode & SPI_CPHA) > + val |= 4; > + ls7a_spi_write_reg(ls7a_spi, SPCR, val); > + val = ls7a_spi_read_reg(ls7a_spi, SPER); > + ls7a_spi_write_reg(ls7a_spi, SPER, val); > + ls7a_spi->mode = spi->mode; > + } > + return 0; I'm sorry that I hadn't review very carefully in V4 and you need to send another new version. In kernel code we usually keep a blank line before the last "return xxx" in a function, and there are several other places with the same problem. Huacai > +} > + > +static void ls7a_spi_set_cs(struct spi_device *spi, bool enable) > +{ > + struct ls7a_spi *ls7a_spi; > + int cs; > + > + ls7a_spi = spi_master_get_devdata(spi->master); > + > + cs = ls7a_spi_read_reg(ls7a_spi, SFC_SOFTCS) & ~(0x11 << spi->chip_select); > + > + if (!!(spi->mode & SPI_CS_HIGH) == enable) > + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x1 << spi->chip_select) | cs); > + else > + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x11 << spi->chip_select) | cs); > +} > + > +static int ls7a_spi_setup_transfer(struct spi_device *spi, > + struct spi_transfer *t) > +{ > + unsigned int hz; > + unsigned int div, div_tmp; > + unsigned int bit; > + unsigned long clk; > + unsigned char val; > + unsigned char spcr, sper; > + const char rdiv[12] = {0, 1, 4, 2, 3, 5, 6, 7, 8, 9, 10, 11}; > + struct ls7a_spi *ls7a_spi; > + > + ls7a_spi = spi_master_get_devdata(spi->master); > + > + if (t) { > + hz = t->speed_hz; > + if (!hz) > + hz = spi->max_speed_hz; > + } else { > + hz = spi->max_speed_hz; > + } > + > + if (hz & (ls7a_spi->hz != hz)) { > + clk = 100000000; > + > + div = DIV_ROUND_UP(clk, hz); > + if (div < 2) > + div = 2; > + if (div > 4096) > + div = 4096; > + > + bit = fls(div) - 1; > + if ((1 << bit) == div) > + bit--; > + div_tmp = rdiv[bit]; > + > + dev_dbg(&spi->dev, "clk = %ld hz = %d div_tmp = %d bit = %d\n", > + clk, hz, div_tmp, bit); > + > + ls7a_spi->hz = hz; > + spcr = div_tmp & 3; > + sper = (div_tmp >> 2) & 3; > + > + val = ls7a_spi_read_reg(ls7a_spi, SPCR); > + ls7a_spi_write_reg(ls7a_spi, SPCR, (val & ~3) | spcr); > + val = ls7a_spi_read_reg(ls7a_spi, SPER); > + ls7a_spi_write_reg(ls7a_spi, SPER, (val & ~3) | sper); > + } > + return 0; > +} > + > +static int ls7a_spi_setup(struct spi_device *spi) > +{ > + return ls7a_spi_setup_transfer(spi, NULL); > +} > + > +static int ls7a_spi_write_read_8bit(struct spi_device *spi, > + const u8 **tx_buf, u8 **rx_buf, > + unsigned int num) > +{ > + struct ls7a_spi *ls7a_spi; > + > + ls7a_spi = spi_master_get_devdata(spi->master); > + > + if (tx_buf && *tx_buf) { > + ls7a_spi_write_reg(ls7a_spi, FIFO, *((*tx_buf)++)); > + > + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x4) == 1) > + ; > + } else { > + ls7a_spi_write_reg(ls7a_spi, FIFO, 0); > + > + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x1) == 1) > + ; > + } > + > + if (rx_buf && *rx_buf) > + *(*rx_buf)++ = ls7a_spi_read_reg(ls7a_spi, FIFO); > + else > + ls7a_spi_read_reg(ls7a_spi, FIFO); > + > + return 1; > +} > + > +static unsigned int ls7a_spi_write_read(struct spi_device *spi, > + struct spi_transfer *xfer) > +{ > + unsigned int count; > + const u8 *tx = xfer->tx_buf; > + u8 *rx = xfer->rx_buf; > + > + count = xfer->len; > + > + do { > + if (ls7a_spi_write_read_8bit(spi, &tx, &rx, count) < 0) > + goto out; > + count--; > + } while (count); > + > +out: > + return xfer->len - count; > +} > + > +static int ls7a_spi_transfer_one(struct spi_master *master, > + struct spi_device *spi, > + struct spi_transfer *t) > +{ > + int status = 0; > + > + status = ls7a_spi_setup_transfer(spi, t); > + if (status < 0) > + return status; > + > + if (t->len) > + ls7a_spi_write_read(spi, t); > + > + return status; > +} > + > +static int ls7a_spi_pci_probe(struct pci_dev *pdev, > + const struct pci_device_id *ent) > +{ > + struct spi_master *master; > + struct ls7a_spi *spi; > + int ret; > + > + master = devm_spi_alloc_master(&pdev->dev, sizeof(*spi)); > + if (!master) > + return -ENOMEM; > + > + spi = spi_master_get_devdata(master); > + ret = pcim_enable_device(pdev); > + if (ret) > + goto err_free_master; > + > + ret = pci_request_regions(pdev, "ls7a-spi"); > + if (ret) > + goto err_free_master; > + > + spi->base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); > + if (!spi->base) { > + ret = -EINVAL; > + goto err_free_master; > + } > + ls7a_spi_write_reg(spi, SPCR, 0x51); > + ls7a_spi_write_reg(spi, SPER, 0x00); > + ls7a_spi_write_reg(spi, SFC_TIMING, 0x01); > + ls7a_spi_write_reg(spi, SFC_PARAM, 0x40); > + spi->mode = 0; > + > + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; > + master->set_cs = ls7a_spi_set_cs; > + master->prepare_message = ls7a_spi_prepare_message; > + master->setup = ls7a_spi_setup; > + master->transfer_one = ls7a_spi_transfer_one; > + master->bits_per_word_mask = SPI_BPW_MASK(8); > + master->num_chipselect = 4; > + master->dev.of_node = pdev->dev.of_node; > + > + spi->master = master; > + > + pci_set_drvdata(pdev, master); > + > + ret = spi_register_master(master); > + if (ret) > + goto err_free_master; > + > + return 0; > + > +err_free_master: > + pci_release_regions(pdev); > + return ret; > +} > + > +static void ls7a_spi_pci_remove(struct pci_dev *pdev) > +{ > + struct spi_master *master = pci_get_drvdata(pdev); > + > + spi_unregister_master(master); > + pci_release_regions(pdev); > +} > + > +static const struct pci_device_id ls7a_spi_pci_id_table[] = { > + { PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a0b) }, > + { 0, } > +}; > + > +MODULE_DEVICE_TABLE(pci, ls7a_spi_pci_id_table); > + > +static struct pci_driver ls7a_spi_pci_driver = { > + .name = "ls7a-spi", > + .id_table = ls7a_spi_pci_id_table, > + .probe = ls7a_spi_pci_probe, > + .remove = ls7a_spi_pci_remove, > +}; > + > +module_pci_driver(ls7a_spi_pci_driver); > + > +MODULE_AUTHOR("Juxin Gao <gaojuxin@loongson.cn>"); > +MODULE_AUTHOR("Qing Zhang <zhangqing@loongson.cn>"); > +MODULE_DESCRIPTION("Loongson LS7A SPI controller driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.1.0 >
Hi, Huacai On 12/28/2020 08:32 AM, Huacai Chen wrote: > Hi, Qing, > > On Sat, Dec 26, 2020 at 5:13 PM Qing Zhang <zhangqing@loongson.cn> wrote: >> The SPI controller has the following characteristics: >> >> - Full-duplex synchronous serial data transmission >> - Support up to 4 variable length byte transmission >> - Main mode support >> - Mode failure generates an error flag and issues an interrupt request >> - Double buffer receiver >> - Serial clock with programmable polarity and phase >> - SPI can be controlled in wait mode >> - Support boot from SPI >> >> Use mtd_debug tool to earse/write/read /dev/mtd0 on development. >> >> eg: >> >> [root@linux mtd-utils-1.0.0]# mtd_debug erase /dev/mtd0 0x20000 0x40000 >> Erased 262144 bytes from address 0x00020000 in flash >> [root@linux mtd-utils-1.0.0]# mtd_debug write /dev/mtd0 0x20000 13 1.img >> Copied 13 bytes from 1.img to address 0x00020000 in flash >> [root@linux mtd-utils-1.0.0]# mtd_debug read /dev/mtd0 0x20000 13 2.img >> Copied 13 bytes from address 0x00020000 in flash to 2.img >> [root@linux mtd-utils-1.0.0]# cmp -l 1.img 2.img >> >> Signed-off-by: Qing Zhang <zhangqing@loongson.cn> >> --- >> >> v2: >> - keep Kconfig and Makefile sorted >> - make the entire comment a C++ one so things look more intentional >> - Fix unclear indentation >> - make conditional statements to improve legibility >> - Don't use static inline >> - the core handle message queue >> - Add a new binding document >> - Fix probe part mixed pdev and PCI >> >> v3: >> - expose set_cs to the core and let it handle things >> - replace transfer_one_message to transfer_one >> - replace spi_alloc_master to devm_spi_alloc_master >> - split out into prepare/unprepare_message >> - releases pci regions before unregister master >> >> v4: >> - names used in the manual >> - rename ls7a_spi_do_transfer to ls7a_spi_setup_transfer >> - change read the spcr and sper outside of this function >> - mode configuration moved to prepare instead >> - remove redundancy code about unprepare/prepare_message >> - used 0x4 instead of 0x1,WFEMPTY instead of RFEMPTY >> >> v5: >> - remove unnecessary blank lines >> >> --- >> drivers/spi/Kconfig | 7 ++ >> drivers/spi/Makefile | 1 + >> drivers/spi/spi-ls7a.c | 280 +++++++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 288 insertions(+) >> create mode 100644 drivers/spi/spi-ls7a.c >> >> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig >> index aadaea0..af7c0d4 100644 >> --- a/drivers/spi/Kconfig >> +++ b/drivers/spi/Kconfig >> @@ -413,6 +413,13 @@ config SPI_LP8841_RTC >> Say N here unless you plan to run the kernel on an ICP DAS >> LP-8x4x industrial computer. >> >> +config SPI_LS7A >> + tristate "Loongson LS7A SPI Controller Support" >> + depends on CPU_LOONGSON64 || COMPILE_TEST >> + help >> + This drivers supports the Loongson LS7A SPI controller in master >> + SPI mode. >> + >> config SPI_MPC52xx >> tristate "Freescale MPC52xx SPI (non-PSC) controller support" >> depends on PPC_MPC52xx >> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile >> index 6fea582..d015cf2 100644 >> --- a/drivers/spi/Makefile >> +++ b/drivers/spi/Makefile >> @@ -61,6 +61,7 @@ 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_LP8841_RTC) += spi-lp8841-rtc.o >> +obj-$(CONFIG_SPI_LS7A) += spi-ls7a.o >> obj-$(CONFIG_SPI_MESON_SPICC) += spi-meson-spicc.o >> obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o >> obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o >> diff --git a/drivers/spi/spi-ls7a.c b/drivers/spi/spi-ls7a.c >> new file mode 100644 >> index 0000000..d24b6d91 >> --- /dev/null >> +++ b/drivers/spi/spi-ls7a.c >> @@ -0,0 +1,280 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +// >> +// Loongson LS7A SPI Controller driver >> +// >> +// Copyright (C) 2020 Loongson Technology Corporation Limited. >> +// >> + >> +#include <linux/module.h> >> +#include <linux/pci.h> >> +#include <linux/spi/spi.h> >> + >> +/* define spi register */ >> +#define SPCR 0x00 >> +#define SPSR 0x01 >> +#define FIFO 0x02 >> +#define SPER 0x03 >> +#define SFC_PARAM 0x04 >> +#define SFC_SOFTCS 0x05 >> +#define SFC_TIMING 0x06 >> + >> +struct ls7a_spi { >> + struct spi_master *master; >> + void __iomem *base; >> + unsigned int hz; >> + unsigned int mode; >> +}; >> + >> +static void ls7a_spi_write_reg(struct ls7a_spi *spi, >> + unsigned char reg, >> + unsigned char data) >> +{ >> + writeb(data, spi->base + reg); >> +} >> + >> +static char ls7a_spi_read_reg(struct ls7a_spi *spi, unsigned char reg) >> +{ >> + return readb(spi->base + reg); >> +} >> + >> +static int ls7a_spi_prepare_message(struct spi_master *master, >> + struct spi_message *msg) >> +{ >> + struct ls7a_spi *ls7a_spi; >> + struct spi_device *spi = msg->spi; >> + unsigned char val; >> + >> + ls7a_spi = spi_master_get_devdata(master); >> + >> + if (ls7a_spi->mode != spi->mode) { >> + val = ls7a_spi_read_reg(ls7a_spi, SPCR); >> + val &= ~0xc; >> + if (spi->mode & SPI_CPOL) >> + val |= 8; >> + if (spi->mode & SPI_CPHA) >> + val |= 4; >> + ls7a_spi_write_reg(ls7a_spi, SPCR, val); >> + val = ls7a_spi_read_reg(ls7a_spi, SPER); >> + ls7a_spi_write_reg(ls7a_spi, SPER, val); >> + ls7a_spi->mode = spi->mode; >> + } >> + return 0; > I'm sorry that I hadn't review very carefully in V4 and you need to > send another new version. In kernel code we usually keep a blank line > before the last "return xxx" in a function, and there are several > other places with the same problem. > > Huacai Thank you again for your reply and suggestions, I will send v6 in the soon. Thanks, -Qing > >> +} >> + >> +static void ls7a_spi_set_cs(struct spi_device *spi, bool enable) >> +{ >> + struct ls7a_spi *ls7a_spi; >> + int cs; >> + >> + ls7a_spi = spi_master_get_devdata(spi->master); >> + >> + cs = ls7a_spi_read_reg(ls7a_spi, SFC_SOFTCS) & ~(0x11 << spi->chip_select); >> + >> + if (!!(spi->mode & SPI_CS_HIGH) == enable) >> + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x1 << spi->chip_select) | cs); >> + else >> + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x11 << spi->chip_select) | cs); >> +} >> + >> +static int ls7a_spi_setup_transfer(struct spi_device *spi, >> + struct spi_transfer *t) >> +{ >> + unsigned int hz; >> + unsigned int div, div_tmp; >> + unsigned int bit; >> + unsigned long clk; >> + unsigned char val; >> + unsigned char spcr, sper; >> + const char rdiv[12] = {0, 1, 4, 2, 3, 5, 6, 7, 8, 9, 10, 11}; >> + struct ls7a_spi *ls7a_spi; >> + >> + ls7a_spi = spi_master_get_devdata(spi->master); >> + >> + if (t) { >> + hz = t->speed_hz; >> + if (!hz) >> + hz = spi->max_speed_hz; >> + } else { >> + hz = spi->max_speed_hz; >> + } >> + >> + if (hz & (ls7a_spi->hz != hz)) { >> + clk = 100000000; >> + >> + div = DIV_ROUND_UP(clk, hz); >> + if (div < 2) >> + div = 2; >> + if (div > 4096) >> + div = 4096; >> + >> + bit = fls(div) - 1; >> + if ((1 << bit) == div) >> + bit--; >> + div_tmp = rdiv[bit]; >> + >> + dev_dbg(&spi->dev, "clk = %ld hz = %d div_tmp = %d bit = %d\n", >> + clk, hz, div_tmp, bit); >> + >> + ls7a_spi->hz = hz; >> + spcr = div_tmp & 3; >> + sper = (div_tmp >> 2) & 3; >> + >> + val = ls7a_spi_read_reg(ls7a_spi, SPCR); >> + ls7a_spi_write_reg(ls7a_spi, SPCR, (val & ~3) | spcr); >> + val = ls7a_spi_read_reg(ls7a_spi, SPER); >> + ls7a_spi_write_reg(ls7a_spi, SPER, (val & ~3) | sper); >> + } >> + return 0; >> +} >> + >> +static int ls7a_spi_setup(struct spi_device *spi) >> +{ >> + return ls7a_spi_setup_transfer(spi, NULL); >> +} >> + >> +static int ls7a_spi_write_read_8bit(struct spi_device *spi, >> + const u8 **tx_buf, u8 **rx_buf, >> + unsigned int num) >> +{ >> + struct ls7a_spi *ls7a_spi; >> + >> + ls7a_spi = spi_master_get_devdata(spi->master); >> + >> + if (tx_buf && *tx_buf) { >> + ls7a_spi_write_reg(ls7a_spi, FIFO, *((*tx_buf)++)); >> + >> + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x4) == 1) >> + ; >> + } else { >> + ls7a_spi_write_reg(ls7a_spi, FIFO, 0); >> + >> + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x1) == 1) >> + ; >> + } >> + >> + if (rx_buf && *rx_buf) >> + *(*rx_buf)++ = ls7a_spi_read_reg(ls7a_spi, FIFO); >> + else >> + ls7a_spi_read_reg(ls7a_spi, FIFO); >> + >> + return 1; >> +} >> + >> +static unsigned int ls7a_spi_write_read(struct spi_device *spi, >> + struct spi_transfer *xfer) >> +{ >> + unsigned int count; >> + const u8 *tx = xfer->tx_buf; >> + u8 *rx = xfer->rx_buf; >> + >> + count = xfer->len; >> + >> + do { >> + if (ls7a_spi_write_read_8bit(spi, &tx, &rx, count) < 0) >> + goto out; >> + count--; >> + } while (count); >> + >> +out: >> + return xfer->len - count; >> +} >> + >> +static int ls7a_spi_transfer_one(struct spi_master *master, >> + struct spi_device *spi, >> + struct spi_transfer *t) >> +{ >> + int status = 0; >> + >> + status = ls7a_spi_setup_transfer(spi, t); >> + if (status < 0) >> + return status; >> + >> + if (t->len) >> + ls7a_spi_write_read(spi, t); >> + >> + return status; >> +} >> + >> +static int ls7a_spi_pci_probe(struct pci_dev *pdev, >> + const struct pci_device_id *ent) >> +{ >> + struct spi_master *master; >> + struct ls7a_spi *spi; >> + int ret; >> + >> + master = devm_spi_alloc_master(&pdev->dev, sizeof(*spi)); >> + if (!master) >> + return -ENOMEM; >> + >> + spi = spi_master_get_devdata(master); >> + ret = pcim_enable_device(pdev); >> + if (ret) >> + goto err_free_master; >> + >> + ret = pci_request_regions(pdev, "ls7a-spi"); >> + if (ret) >> + goto err_free_master; >> + >> + spi->base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); >> + if (!spi->base) { >> + ret = -EINVAL; >> + goto err_free_master; >> + } >> + ls7a_spi_write_reg(spi, SPCR, 0x51); >> + ls7a_spi_write_reg(spi, SPER, 0x00); >> + ls7a_spi_write_reg(spi, SFC_TIMING, 0x01); >> + ls7a_spi_write_reg(spi, SFC_PARAM, 0x40); >> + spi->mode = 0; >> + >> + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; >> + master->set_cs = ls7a_spi_set_cs; >> + master->prepare_message = ls7a_spi_prepare_message; >> + master->setup = ls7a_spi_setup; >> + master->transfer_one = ls7a_spi_transfer_one; >> + master->bits_per_word_mask = SPI_BPW_MASK(8); >> + master->num_chipselect = 4; >> + master->dev.of_node = pdev->dev.of_node; >> + >> + spi->master = master; >> + >> + pci_set_drvdata(pdev, master); >> + >> + ret = spi_register_master(master); >> + if (ret) >> + goto err_free_master; >> + >> + return 0; >> + >> +err_free_master: >> + pci_release_regions(pdev); >> + return ret; >> +} >> + >> +static void ls7a_spi_pci_remove(struct pci_dev *pdev) >> +{ >> + struct spi_master *master = pci_get_drvdata(pdev); >> + >> + spi_unregister_master(master); >> + pci_release_regions(pdev); >> +} >> + >> +static const struct pci_device_id ls7a_spi_pci_id_table[] = { >> + { PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a0b) }, >> + { 0, } >> +}; >> + >> +MODULE_DEVICE_TABLE(pci, ls7a_spi_pci_id_table); >> + >> +static struct pci_driver ls7a_spi_pci_driver = { >> + .name = "ls7a-spi", >> + .id_table = ls7a_spi_pci_id_table, >> + .probe = ls7a_spi_pci_probe, >> + .remove = ls7a_spi_pci_remove, >> +}; >> + >> +module_pci_driver(ls7a_spi_pci_driver); >> + >> +MODULE_AUTHOR("Juxin Gao <gaojuxin@loongson.cn>"); >> +MODULE_AUTHOR("Qing Zhang <zhangqing@loongson.cn>"); >> +MODULE_DESCRIPTION("Loongson LS7A SPI controller driver"); >> +MODULE_LICENSE("GPL v2"); >> -- >> 2.1.0 >>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index aadaea0..af7c0d4 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -413,6 +413,13 @@ config SPI_LP8841_RTC Say N here unless you plan to run the kernel on an ICP DAS LP-8x4x industrial computer. +config SPI_LS7A + tristate "Loongson LS7A SPI Controller Support" + depends on CPU_LOONGSON64 || COMPILE_TEST + help + This drivers supports the Loongson LS7A SPI controller in master + SPI mode. + config SPI_MPC52xx tristate "Freescale MPC52xx SPI (non-PSC) controller support" depends on PPC_MPC52xx diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 6fea582..d015cf2 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -61,6 +61,7 @@ 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_LP8841_RTC) += spi-lp8841-rtc.o +obj-$(CONFIG_SPI_LS7A) += spi-ls7a.o obj-$(CONFIG_SPI_MESON_SPICC) += spi-meson-spicc.o obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o obj-$(CONFIG_SPI_MPC512x_PSC) += spi-mpc512x-psc.o diff --git a/drivers/spi/spi-ls7a.c b/drivers/spi/spi-ls7a.c new file mode 100644 index 0000000..d24b6d91 --- /dev/null +++ b/drivers/spi/spi-ls7a.c @@ -0,0 +1,280 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Loongson LS7A SPI Controller driver +// +// Copyright (C) 2020 Loongson Technology Corporation Limited. +// + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/spi/spi.h> + +/* define spi register */ +#define SPCR 0x00 +#define SPSR 0x01 +#define FIFO 0x02 +#define SPER 0x03 +#define SFC_PARAM 0x04 +#define SFC_SOFTCS 0x05 +#define SFC_TIMING 0x06 + +struct ls7a_spi { + struct spi_master *master; + void __iomem *base; + unsigned int hz; + unsigned int mode; +}; + +static void ls7a_spi_write_reg(struct ls7a_spi *spi, + unsigned char reg, + unsigned char data) +{ + writeb(data, spi->base + reg); +} + +static char ls7a_spi_read_reg(struct ls7a_spi *spi, unsigned char reg) +{ + return readb(spi->base + reg); +} + +static int ls7a_spi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct ls7a_spi *ls7a_spi; + struct spi_device *spi = msg->spi; + unsigned char val; + + ls7a_spi = spi_master_get_devdata(master); + + if (ls7a_spi->mode != spi->mode) { + val = ls7a_spi_read_reg(ls7a_spi, SPCR); + val &= ~0xc; + if (spi->mode & SPI_CPOL) + val |= 8; + if (spi->mode & SPI_CPHA) + val |= 4; + ls7a_spi_write_reg(ls7a_spi, SPCR, val); + val = ls7a_spi_read_reg(ls7a_spi, SPER); + ls7a_spi_write_reg(ls7a_spi, SPER, val); + ls7a_spi->mode = spi->mode; + } + return 0; +} + +static void ls7a_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct ls7a_spi *ls7a_spi; + int cs; + + ls7a_spi = spi_master_get_devdata(spi->master); + + cs = ls7a_spi_read_reg(ls7a_spi, SFC_SOFTCS) & ~(0x11 << spi->chip_select); + + if (!!(spi->mode & SPI_CS_HIGH) == enable) + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x1 << spi->chip_select) | cs); + else + ls7a_spi_write_reg(ls7a_spi, SFC_SOFTCS, (0x11 << spi->chip_select) | cs); +} + +static int ls7a_spi_setup_transfer(struct spi_device *spi, + struct spi_transfer *t) +{ + unsigned int hz; + unsigned int div, div_tmp; + unsigned int bit; + unsigned long clk; + unsigned char val; + unsigned char spcr, sper; + const char rdiv[12] = {0, 1, 4, 2, 3, 5, 6, 7, 8, 9, 10, 11}; + struct ls7a_spi *ls7a_spi; + + ls7a_spi = spi_master_get_devdata(spi->master); + + if (t) { + hz = t->speed_hz; + if (!hz) + hz = spi->max_speed_hz; + } else { + hz = spi->max_speed_hz; + } + + if (hz & (ls7a_spi->hz != hz)) { + clk = 100000000; + + div = DIV_ROUND_UP(clk, hz); + if (div < 2) + div = 2; + if (div > 4096) + div = 4096; + + bit = fls(div) - 1; + if ((1 << bit) == div) + bit--; + div_tmp = rdiv[bit]; + + dev_dbg(&spi->dev, "clk = %ld hz = %d div_tmp = %d bit = %d\n", + clk, hz, div_tmp, bit); + + ls7a_spi->hz = hz; + spcr = div_tmp & 3; + sper = (div_tmp >> 2) & 3; + + val = ls7a_spi_read_reg(ls7a_spi, SPCR); + ls7a_spi_write_reg(ls7a_spi, SPCR, (val & ~3) | spcr); + val = ls7a_spi_read_reg(ls7a_spi, SPER); + ls7a_spi_write_reg(ls7a_spi, SPER, (val & ~3) | sper); + } + return 0; +} + +static int ls7a_spi_setup(struct spi_device *spi) +{ + return ls7a_spi_setup_transfer(spi, NULL); +} + +static int ls7a_spi_write_read_8bit(struct spi_device *spi, + const u8 **tx_buf, u8 **rx_buf, + unsigned int num) +{ + struct ls7a_spi *ls7a_spi; + + ls7a_spi = spi_master_get_devdata(spi->master); + + if (tx_buf && *tx_buf) { + ls7a_spi_write_reg(ls7a_spi, FIFO, *((*tx_buf)++)); + + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x4) == 1) + ; + } else { + ls7a_spi_write_reg(ls7a_spi, FIFO, 0); + + while ((ls7a_spi_read_reg(ls7a_spi, SPSR) & 0x1) == 1) + ; + } + + if (rx_buf && *rx_buf) + *(*rx_buf)++ = ls7a_spi_read_reg(ls7a_spi, FIFO); + else + ls7a_spi_read_reg(ls7a_spi, FIFO); + + return 1; +} + +static unsigned int ls7a_spi_write_read(struct spi_device *spi, + struct spi_transfer *xfer) +{ + unsigned int count; + const u8 *tx = xfer->tx_buf; + u8 *rx = xfer->rx_buf; + + count = xfer->len; + + do { + if (ls7a_spi_write_read_8bit(spi, &tx, &rx, count) < 0) + goto out; + count--; + } while (count); + +out: + return xfer->len - count; +} + +static int ls7a_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + int status = 0; + + status = ls7a_spi_setup_transfer(spi, t); + if (status < 0) + return status; + + if (t->len) + ls7a_spi_write_read(spi, t); + + return status; +} + +static int ls7a_spi_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct spi_master *master; + struct ls7a_spi *spi; + int ret; + + master = devm_spi_alloc_master(&pdev->dev, sizeof(*spi)); + if (!master) + return -ENOMEM; + + spi = spi_master_get_devdata(master); + ret = pcim_enable_device(pdev); + if (ret) + goto err_free_master; + + ret = pci_request_regions(pdev, "ls7a-spi"); + if (ret) + goto err_free_master; + + spi->base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); + if (!spi->base) { + ret = -EINVAL; + goto err_free_master; + } + ls7a_spi_write_reg(spi, SPCR, 0x51); + ls7a_spi_write_reg(spi, SPER, 0x00); + ls7a_spi_write_reg(spi, SFC_TIMING, 0x01); + ls7a_spi_write_reg(spi, SFC_PARAM, 0x40); + spi->mode = 0; + + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->set_cs = ls7a_spi_set_cs; + master->prepare_message = ls7a_spi_prepare_message; + master->setup = ls7a_spi_setup; + master->transfer_one = ls7a_spi_transfer_one; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->num_chipselect = 4; + master->dev.of_node = pdev->dev.of_node; + + spi->master = master; + + pci_set_drvdata(pdev, master); + + ret = spi_register_master(master); + if (ret) + goto err_free_master; + + return 0; + +err_free_master: + pci_release_regions(pdev); + return ret; +} + +static void ls7a_spi_pci_remove(struct pci_dev *pdev) +{ + struct spi_master *master = pci_get_drvdata(pdev); + + spi_unregister_master(master); + pci_release_regions(pdev); +} + +static const struct pci_device_id ls7a_spi_pci_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a0b) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, ls7a_spi_pci_id_table); + +static struct pci_driver ls7a_spi_pci_driver = { + .name = "ls7a-spi", + .id_table = ls7a_spi_pci_id_table, + .probe = ls7a_spi_pci_probe, + .remove = ls7a_spi_pci_remove, +}; + +module_pci_driver(ls7a_spi_pci_driver); + +MODULE_AUTHOR("Juxin Gao <gaojuxin@loongson.cn>"); +MODULE_AUTHOR("Qing Zhang <zhangqing@loongson.cn>"); +MODULE_DESCRIPTION("Loongson LS7A SPI controller driver"); +MODULE_LICENSE("GPL v2");
The SPI controller has the following characteristics: - Full-duplex synchronous serial data transmission - Support up to 4 variable length byte transmission - Main mode support - Mode failure generates an error flag and issues an interrupt request - Double buffer receiver - Serial clock with programmable polarity and phase - SPI can be controlled in wait mode - Support boot from SPI Use mtd_debug tool to earse/write/read /dev/mtd0 on development. eg: [root@linux mtd-utils-1.0.0]# mtd_debug erase /dev/mtd0 0x20000 0x40000 Erased 262144 bytes from address 0x00020000 in flash [root@linux mtd-utils-1.0.0]# mtd_debug write /dev/mtd0 0x20000 13 1.img Copied 13 bytes from 1.img to address 0x00020000 in flash [root@linux mtd-utils-1.0.0]# mtd_debug read /dev/mtd0 0x20000 13 2.img Copied 13 bytes from address 0x00020000 in flash to 2.img [root@linux mtd-utils-1.0.0]# cmp -l 1.img 2.img Signed-off-by: Qing Zhang <zhangqing@loongson.cn> --- v2: - keep Kconfig and Makefile sorted - make the entire comment a C++ one so things look more intentional - Fix unclear indentation - make conditional statements to improve legibility - Don't use static inline - the core handle message queue - Add a new binding document - Fix probe part mixed pdev and PCI v3: - expose set_cs to the core and let it handle things - replace transfer_one_message to transfer_one - replace spi_alloc_master to devm_spi_alloc_master - split out into prepare/unprepare_message - releases pci regions before unregister master v4: - names used in the manual - rename ls7a_spi_do_transfer to ls7a_spi_setup_transfer - change read the spcr and sper outside of this function - mode configuration moved to prepare instead - remove redundancy code about unprepare/prepare_message - used 0x4 instead of 0x1,WFEMPTY instead of RFEMPTY v5: - remove unnecessary blank lines --- drivers/spi/Kconfig | 7 ++ drivers/spi/Makefile | 1 + drivers/spi/spi-ls7a.c | 280 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 288 insertions(+) create mode 100644 drivers/spi/spi-ls7a.c