| Message ID | 20220705204743.3224692-10-colin.foster@in-advantage.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | add support for VSC7512 control over SPI | expand |
On Tue, Jul 05, 2022 at 01:47:43PM -0700, Colin Foster wrote: > The VSC7512 is a networking chip that contains several peripherals. Many of > these peripherals are currently supported by the VSC7513 and VSC7514 chips, > but those run on an internal CPU. The VSC7512 lacks this CPU, and must be > controlled externally. > > Utilize the existing drivers by referencing the chip as an MFD. Add support > for the two MDIO buses, the internal phys, pinctrl, and serial GPIO. > > Signed-off-by: Colin Foster <colin.foster@in-advantage.com> > --- Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
On Tue, 05 Jul 2022, Colin Foster wrote: > The VSC7512 is a networking chip that contains several peripherals. Many of > these peripherals are currently supported by the VSC7513 and VSC7514 chips, > but those run on an internal CPU. The VSC7512 lacks this CPU, and must be > controlled externally. > > Utilize the existing drivers by referencing the chip as an MFD. Add support > for the two MDIO buses, the internal phys, pinctrl, and serial GPIO. > > Signed-off-by: Colin Foster <colin.foster@in-advantage.com> > --- > MAINTAINERS | 1 + > drivers/mfd/Kconfig | 21 +++ > drivers/mfd/Makefile | 3 + > drivers/mfd/ocelot-core.c | 169 ++++++++++++++++++++ > drivers/mfd/ocelot-spi.c | 317 ++++++++++++++++++++++++++++++++++++++ > drivers/mfd/ocelot.h | 34 ++++ > 6 files changed, 545 insertions(+) > create mode 100644 drivers/mfd/ocelot-core.c > create mode 100644 drivers/mfd/ocelot-spi.c > create mode 100644 drivers/mfd/ocelot.h Generally this is looking much better. Almost ready for inclusion with just a few nits. > diff --git a/MAINTAINERS b/MAINTAINERS > index 5e798c42fa08..e3299677cd4a 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -14471,6 +14471,7 @@ OCELOT EXTERNAL SWITCH CONTROL > M: Colin Foster <colin.foster@in-advantage.com> > S: Supported > F: Documentation/devicetree/bindings/mfd/mscc,ocelot.yaml > +F: drivers/mfd/ocelot* > F: include/linux/mfd/ocelot.h > > OCXL (Open Coherent Accelerator Processor Interface OpenCAPI) DRIVER > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig > index 3b59456f5545..0ef433d170dc 100644 > --- a/drivers/mfd/Kconfig > +++ b/drivers/mfd/Kconfig > @@ -962,6 +962,27 @@ config MFD_MENF21BMC > This driver can also be built as a module. If so the module > will be called menf21bmc. > > +config MFD_OCELOT > + tristate "Microsemi Ocelot External Control Support" > + depends on SPI_MASTER > + select MFD_CORE > + select REGMAP_SPI > + help > + Ocelot is a family of networking chips that support multiple ethernet > + and fibre interfaces. In addition to networking, they contain several > + other functions, including pinctrl, MDIO, and communication with > + external chips. While some chips have an internal processor capable of > + running an OS, others don't. All chips can be controlled externally > + through different interfaces, including SPI, I2C, and PCIe. > + > + Say yes here to add support for Ocelot chips (VSC7511, VSC7512, > + VSC7513, VSC7514) controlled externally. > + > + To compile this driver as a module, choose M here: the module will be > + called ocelot-soc. > + > + If unsure, say N. > + > config EZX_PCAP > bool "Motorola EZXPCAP Support" > depends on SPI_MASTER > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile > index 858cacf659d6..0004b7e86220 100644 > --- a/drivers/mfd/Makefile > +++ b/drivers/mfd/Makefile > @@ -120,6 +120,9 @@ obj-$(CONFIG_MFD_MC13XXX_I2C) += mc13xxx-i2c.o > > obj-$(CONFIG_MFD_CORE) += mfd-core.o > > +ocelot-soc-objs := ocelot-core.o ocelot-spi.o > +obj-$(CONFIG_MFD_OCELOT) += ocelot-soc.o > + > obj-$(CONFIG_EZX_PCAP) += ezx-pcap.o > obj-$(CONFIG_MFD_CPCAP) += motorola-cpcap.o > > diff --git a/drivers/mfd/ocelot-core.c b/drivers/mfd/ocelot-core.c > new file mode 100644 > index 000000000000..e07cd901e1b3 > --- /dev/null > +++ b/drivers/mfd/ocelot-core.c > @@ -0,0 +1,169 @@ > +// SPDX-License-Identifier: (GPL-2.0 OR MIT) > +/* > + * Core driver for the Ocelot chip family. > + * > + * The VSC7511, 7512, 7513, and 7514 can be controlled internally via an > + * on-chip MIPS processor, or externally via SPI, I2C, PCIe. This core driver is > + * intended to be the bus-agnostic glue between, for example, the SPI bus and > + * the child devices. > + * > + * Copyright 2021, 2022 Innovative Advantage Inc. Range? > + * Author: Colin Foster <colin.foster@in-advantage.com> > + */ > + > +#include <linux/kernel.h> > +#include <linux/mfd/core.h> > +#include <linux/mfd/ocelot.h> > +#include <linux/module.h> > +#include <linux/regmap.h> > +#include <linux/types.h> > + > +#include <soc/mscc/ocelot.h> > + > +#include "ocelot.h" > + > +#define REG_GCB_SOFT_RST 0x0008 > + > +#define BIT_SOFT_CHIP_RST BIT(0) > + > +#define VSC7512_MIIM0_RES_START 0x7107009c > +#define VSC7512_MIIM0_RES_SIZE 0x24 > + > +#define VSC7512_MIIM1_RES_START 0x710700c0 > +#define VSC7512_MIIM1_RES_SIZE 0x24 Maybe: #define VSC7512_MIIM0_RES_START 0x7107009c #define VSC7512_MIIM1_RES_START 0x710700c0 #define VSC7512_MIIM_RES_SIZE 0x24 No strong feelings about this though, just saves a line or two. > +#define VSC7512_PHY_RES_START 0x710700f0 > +#define VSC7512_PHY_RES_SIZE 0x4 > + > +#define VSC7512_GPIO_RES_START 0x71070034 > +#define VSC7512_GPIO_RES_SIZE 0x6c > + > +#define VSC7512_SIO_CTRL_RES_START 0x710700f8 > +#define VSC7512_SIO_CTRL_RES_SIZE 0x100 > + > +#define VSC7512_GCB_RST_SLEEP_US 100 > +#define VSC7512_GCB_RST_TIMEOUT_US 100000 > + > +static int ocelot_gcb_chip_rst_status(struct ocelot_ddata *ddata) > +{ > + int val, err; > + > + err = regmap_read(ddata->gcb_regmap, REG_GCB_SOFT_RST, &val); > + if (err) > + val = err; I think just returning err is clearer. > + return val; > +} > + > +int ocelot_chip_reset(struct device *dev) > +{ > + struct ocelot_ddata *ddata = dev_get_drvdata(dev); > + int ret, val; > + > + /* > + * Reset the entire chip here to put it into a completely known state. > + * Other drivers may want to reset their own subsystems. The register > + * self-clears, so one write is all that is needed and wait for it to > + * clear. > + */ > + ret = regmap_write(ddata->gcb_regmap, REG_GCB_SOFT_RST, > + BIT_SOFT_CHIP_RST); Lots of these line-breaks can be removed which will tidy-up the file quite a bit. The new max is 100 chars. So long as checkpatch.pl doesn't complain, I'm happy. > + if (ret) > + return ret; > + > + ret = readx_poll_timeout(ocelot_gcb_chip_rst_status, ddata, val, !val, > + VSC7512_GCB_RST_SLEEP_US, > + VSC7512_GCB_RST_TIMEOUT_US); > + if (ret) > + return dev_err_probe(ddata->dev, ret, "timeout: chip reset\n"); *This* function is not probe. Also the last failure will produce 2 prints due to the dev_err_probe() in actual .probe() below. Please fix that. > + return 0; > +} > +EXPORT_SYMBOL_NS(ocelot_chip_reset, MFD_OCELOT); > + > +static const struct resource vsc7512_miim0_resources[] = { > + DEFINE_RES_REG_NAMED(VSC7512_MIIM0_RES_START, VSC7512_MIIM0_RES_SIZE, > + "gcb_miim0"), Lots of early breaks coming up - I won't comment on them all. > + DEFINE_RES_REG_NAMED(VSC7512_PHY_RES_START, VSC7512_PHY_RES_SIZE, > + "gcb_phy"), > +}; > + > +static const struct resource vsc7512_miim1_resources[] = { > + DEFINE_RES_REG_NAMED(VSC7512_MIIM1_RES_START, VSC7512_MIIM1_RES_SIZE, > + "gcb_miim1"), > +}; > + > +static const struct resource vsc7512_pinctrl_resources[] = { > + DEFINE_RES_REG_NAMED(VSC7512_GPIO_RES_START, VSC7512_GPIO_RES_SIZE, > + "gcb_gpio"), > +}; > + > +static const struct resource vsc7512_sgpio_resources[] = { > + DEFINE_RES_REG_NAMED(VSC7512_SIO_CTRL_RES_START, > + VSC7512_SIO_CTRL_RES_SIZE, > + "gcb_sio"), > +}; > + > +static const struct mfd_cell vsc7512_devs[] = { > + { > + .name = "ocelot-pinctrl", > + .of_compatible = "mscc,ocelot-pinctrl", > + .num_resources = ARRAY_SIZE(vsc7512_pinctrl_resources), > + .resources = vsc7512_pinctrl_resources, > + }, { > + .name = "ocelot-sgpio", > + .of_compatible = "mscc,ocelot-sgpio", > + .num_resources = ARRAY_SIZE(vsc7512_sgpio_resources), > + .resources = vsc7512_sgpio_resources, > + }, { > + .name = "ocelot-miim0", > + .of_compatible = "mscc,ocelot-miim", > + .of_reg = VSC7512_MIIM0_RES_START, > + .use_of_reg = true, > + .num_resources = ARRAY_SIZE(vsc7512_miim0_resources), > + .resources = vsc7512_miim0_resources, > + }, { > + .name = "ocelot-miim1", > + .of_compatible = "mscc,ocelot-miim", > + .of_reg = VSC7512_MIIM1_RES_START, > + .use_of_reg = true, > + .num_resources = ARRAY_SIZE(vsc7512_miim1_resources), > + .resources = vsc7512_miim1_resources, > + }, > +}; > + > +static void ocelot_core_try_add_regmap(struct device *dev, > + const struct resource *res) > +{ > + if (!dev_get_regmap(dev, res->name)) > + ocelot_spi_init_regmap(dev, res); This is probably clearer at first-glance for readers: if (dev_get_regmap(dev, res->name)) return; ocelot_spi_init_regmap(dev, res); > +} > + > +static void ocelot_core_try_add_regmaps(struct device *dev, > + const struct mfd_cell *cell) > +{ > + int i; > + > + for (i = 0; i < cell->num_resources; i++) > + ocelot_core_try_add_regmap(dev, &cell->resources[i]); > +} > + > +int ocelot_core_init(struct device *dev) > +{ > + int i, ndevs; > + > + ndevs = ARRAY_SIZE(vsc7512_devs); > + > + for (i = 0; i < ndevs; i++) > + ocelot_core_try_add_regmaps(dev, &vsc7512_devs[i]); > + > + return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, vsc7512_devs, > + ndevs, NULL, 0, NULL); > +} > +EXPORT_SYMBOL_NS(ocelot_core_init, MFD_OCELOT); > + > +MODULE_DESCRIPTION("Externally Controlled Ocelot Chip Driver"); > +MODULE_AUTHOR("Colin Foster <colin.foster@in-advantage.com>"); > +MODULE_LICENSE("GPL"); > +MODULE_IMPORT_NS(MFD_OCELOT_SPI); > diff --git a/drivers/mfd/ocelot-spi.c b/drivers/mfd/ocelot-spi.c > new file mode 100644 > index 000000000000..0c1c5215c706 > --- /dev/null > +++ b/drivers/mfd/ocelot-spi.c > @@ -0,0 +1,317 @@ > +// SPDX-License-Identifier: (GPL-2.0 OR MIT) > +/* > + * SPI core driver for the Ocelot chip family. > + * > + * This driver will handle everything necessary to allow for communication over > + * SPI to the VSC7511, VSC7512, VSC7513 and VSC7514 chips. The main functions > + * are to prepare the chip's SPI interface for a specific bus speed, and a host > + * processor's endianness. This will create and distribute regmaps for any > + * children. > + * > + * Copyright 2021, 2022 Innovative Advantage Inc. > + * > + * Author: Colin Foster <colin.foster@in-advantage.com> > + */ > + > +#include <linux/ioport.h> > +#include <linux/kconfig.h> > +#include <linux/module.h> > +#include <linux/regmap.h> > +#include <linux/spi/spi.h> > + > +#include <asm/byteorder.h> > + > +#include "ocelot.h" > + > +#define REG_DEV_CPUORG_IF_CTRL 0x0000 > +#define REG_DEV_CPUORG_IF_CFGSTAT 0x0004 > + > +#define CFGSTAT_IF_NUM_VCORE (0 << 24) > +#define CFGSTAT_IF_NUM_VRAP (1 << 24) > +#define CFGSTAT_IF_NUM_SI (2 << 24) > +#define CFGSTAT_IF_NUM_MIIM (3 << 24) > + > +#define VSC7512_DEVCPU_ORG_RES_START 0x71000000 > +#define VSC7512_DEVCPU_ORG_RES_SIZE 0x38 > + > +#define VSC7512_CHIP_REGS_RES_START 0x71070000 > +#define VSC7512_CHIP_REGS_RES_SIZE 0x14 > + > +struct spi_device; Why not just #include? > +static const struct resource vsc7512_dev_cpuorg_resource = > + DEFINE_RES_REG_NAMED(VSC7512_DEVCPU_ORG_RES_START, > + VSC7512_DEVCPU_ORG_RES_SIZE, > + "devcpu_org"); > + > +static const struct resource vsc7512_gcb_resource = > + DEFINE_RES_REG_NAMED(VSC7512_CHIP_REGS_RES_START, > + VSC7512_CHIP_REGS_RES_SIZE, > + "devcpu_gcb_chip_regs"); > + > +static int ocelot_spi_initialize(struct device *dev) > +{ > + struct ocelot_ddata *ddata = dev_get_drvdata(dev); > + u32 val, check; > + int err; > + > + val = OCELOT_SPI_BYTE_ORDER; > + > + /* > + * The SPI address must be big-endian, but we want the payload to match > + * our CPU. These are two bits (0 and 1) but they're repeated such that > + * the write from any configuration will be valid. The four > + * configurations are: > + * > + * 0b00: little-endian, MSB first > + * | 111111 | 22221111 | 33222222 | > + * | 76543210 | 54321098 | 32109876 | 10987654 | > + * > + * 0b01: big-endian, MSB first > + * | 33222222 | 22221111 | 111111 | | > + * | 10987654 | 32109876 | 54321098 | 76543210 | > + * > + * 0b10: little-endian, LSB first > + * | 111111 | 11112222 | 22222233 | > + * | 01234567 | 89012345 | 67890123 | 45678901 | > + * > + * 0b11: big-endian, LSB first > + * | 22222233 | 11112222 | 111111 | | > + * | 45678901 | 67890123 | 89012345 | 01234567 | > + */ > + err = regmap_write(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CTRL, val); > + if (err) > + return err; > + > + /* > + * Apply the number of padding bytes between a read request and the data > + * payload. Some registers have access times of up to 1us, so if the > + * first payload bit is shifted out too quickly, the read will fail. > + */ > + val = ddata->spi_padding_bytes; > + err = regmap_write(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CFGSTAT, > + val); > + if (err) > + return err; > + > + /* > + * After we write the interface configuration, read it back here. This > + * will verify several different things. The first is that the number of > + * padding bytes actually got written correctly. These are found in bits > + * 0:3. > + * > + * The second is that bit 16 is cleared. Bit 16 is IF_CFGSTAT:IF_STAT, > + * and will be set if the register access is too fast. This would be in > + * the condition that the number of padding bytes is insufficient for > + * the SPI bus frequency. > + * > + * The last check is for bits 31:24, which define the interface by which > + * the registers are being accessed. Since we're accessing them via the > + * serial interface, it must return IF_NUM_SI. > + */ > + check = val | CFGSTAT_IF_NUM_SI; > + > + err = regmap_read(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CFGSTAT, > + &val); > + if (err) > + return err; > + > + if (check != val) > + return -ENODEV; > + > + return 0; > +} > + > +static const struct regmap_config ocelot_spi_regmap_config = { > + .reg_bits = 24, > + .reg_stride = 4, > + .reg_downshift = 2, > + .val_bits = 32, > + > + .write_flag_mask = 0x80, > + > + .use_single_write = true, > + .can_multi_write = false, > + > + .reg_format_endian = REGMAP_ENDIAN_BIG, > + .val_format_endian = REGMAP_ENDIAN_NATIVE, > +}; > + > +static int ocelot_spi_regmap_bus_read(void *context, > + const void *reg, size_t reg_size, > + void *val, size_t val_size) > +{ > + struct ocelot_ddata *ddata = context; > + struct spi_transfer tx, padding, rx; > + struct spi_device *spi = ddata->spi; > + struct spi_message msg; > + > + spi = ddata->spi; Drop this line. > + spi_message_init(&msg); > + > + memset(&tx, 0, sizeof(tx)); > + > + tx.tx_buf = reg; > + tx.len = reg_size; > + > + spi_message_add_tail(&tx, &msg); > + > + if (ddata->spi_padding_bytes) { > + memset(&padding, 0, sizeof(padding)); > + > + padding.len = ddata->spi_padding_bytes; > + padding.tx_buf = ddata->dummy_buf; > + padding.dummy_data = 1; > + > + spi_message_add_tail(&padding, &msg); > + } > + > + memset(&rx, 0, sizeof(rx)); > + rx.rx_buf = val; > + rx.len = val_size; > + > + spi_message_add_tail(&rx, &msg); > + > + return spi_sync(spi, &msg); > +} > + > +static int ocelot_spi_regmap_bus_write(void *context, const void *data, > + size_t count) > +{ > + struct ocelot_ddata *ddata = context; > + struct spi_device *spi = ddata->spi; > + > + return spi_write(spi, data, count); > +} > + > +static const struct regmap_bus ocelot_spi_regmap_bus = { > + .write = ocelot_spi_regmap_bus_write, > + .read = ocelot_spi_regmap_bus_read, > +}; > + > +struct regmap * > +ocelot_spi_init_regmap(struct device *dev, const struct resource *res) One line, along with all the others. > +{ > + struct ocelot_ddata *ddata = dev_get_drvdata(dev); > + struct regmap_config regmap_config; > + > + memcpy(®map_config, &ocelot_spi_regmap_config, > + sizeof(regmap_config)); > + > + regmap_config.name = res->name; > + regmap_config.max_register = res->end - res->start; > + regmap_config.reg_base = res->start; > + > + return devm_regmap_init(dev, &ocelot_spi_regmap_bus, ddata, > + ®map_config); > +} > +EXPORT_SYMBOL_NS(ocelot_spi_init_regmap, MFD_OCELOT_SPI); > + > +static int ocelot_spi_probe(struct spi_device *spi) > +{ > + struct device *dev = &spi->dev; > + struct ocelot_ddata *ddata; > + struct regmap *r; > + int err; > + > + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); > + if (!ddata) > + return -ENOMEM; > + > + ddata->dev = dev; How are you fetching ddata if you don't already have 'dev'? > + dev_set_drvdata(dev, ddata); This should use the spi_* variant. > + if (spi->max_speed_hz <= 500000) { > + ddata->spi_padding_bytes = 0; > + } else { > + /* > + * Calculation taken from the manual for IF_CFGSTAT:IF_CFG. > + * Register access time is 1us, so we need to configure and send > + * out enough padding bytes between the read request and data > + * transmission that lasts at least 1 microsecond. > + */ > + ddata->spi_padding_bytes = 1 + > + (spi->max_speed_hz / 1000000 + 2) / 8; > + > + ddata->dummy_buf = devm_kzalloc(dev, ddata->spi_padding_bytes, > + GFP_KERNEL); > + if (!ddata->dummy_buf) > + return -ENOMEM; > + } > + > + ddata->spi = spi; If you have 'spi' you definitely do not need 'dev'. You can derive one from the other. > + spi->bits_per_word = 8; > + > + err = spi_setup(spi); > + if (err < 0) > + return dev_err_probe(&spi->dev, err, > + "Error performing SPI setup\n"); > + > + r = ocelot_spi_init_regmap(dev, &vsc7512_dev_cpuorg_resource); > + if (IS_ERR(r)) > + return PTR_ERR(r); > + > + ddata->cpuorg_regmap = r; > + > + r = ocelot_spi_init_regmap(dev, &vsc7512_gcb_resource); > + if (IS_ERR(r)) > + return PTR_ERR(r); > + > + ddata->gcb_regmap = r; > + > + /* > + * The chip must be set up for SPI before it gets initialized and reset. > + * This must be done before calling init, and after a chip reset is > + * performed. > + */ > + err = ocelot_spi_initialize(dev); > + if (err) > + return dev_err_probe(dev, err, "Error initializing SPI bus\n"); > + > + err = ocelot_chip_reset(dev); > + if (err) > + return dev_err_probe(dev, err, "Error resetting device\n"); > + > + /* > + * A chip reset will clear the SPI configuration, so it needs to be done > + * again before we can access any registers > + */ > + err = ocelot_spi_initialize(dev); > + if (err) > + return dev_err_probe(dev, err, > + "Error initializing SPI bus after reset\n"); > + > + err = ocelot_core_init(dev); > + if (err < 0) > + return dev_err_probe(dev, err, > + "Error initializing Ocelot core\n"); > + > + return 0; > +} > + > +static const struct spi_device_id ocelot_spi_ids[] = { > + { "vsc7512", 0 }, > + { } > +}; > + > +static const struct of_device_id ocelot_spi_of_match[] = { > + { .compatible = "mscc,vsc7512" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, ocelot_spi_of_match); > + > +static struct spi_driver ocelot_spi_driver = { > + .driver = { > + .name = "ocelot-soc", > + .of_match_table = ocelot_spi_of_match, > + }, > + .id_table = ocelot_spi_ids, > + .probe = ocelot_spi_probe, > +}; > +module_spi_driver(ocelot_spi_driver); > + > +MODULE_DESCRIPTION("SPI Controlled Ocelot Chip Driver"); > +MODULE_AUTHOR("Colin Foster <colin.foster@in-advantage.com>"); > +MODULE_LICENSE("Dual MIT/GPL"); > +MODULE_IMPORT_NS(MFD_OCELOT); > diff --git a/drivers/mfd/ocelot.h b/drivers/mfd/ocelot.h > new file mode 100644 > index 000000000000..c86bd6990a3c > --- /dev/null > +++ b/drivers/mfd/ocelot.h > @@ -0,0 +1,34 @@ > +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ > +/* Copyright 2021, 2022 Innovative Advantage Inc. */ > + > +#include <asm/byteorder.h> > + > +struct device; > +struct spi_device; > +struct regmap; > +struct resource; > + > +struct ocelot_ddata { > + struct device *dev; > + struct regmap *gcb_regmap; > + struct regmap *cpuorg_regmap; > + int spi_padding_bytes; > + struct spi_device *spi; > + void *dummy_buf; > +}; This looks like it deserves a doc header. > +int ocelot_chip_reset(struct device *dev); > +int ocelot_core_init(struct device *dev); > + > +/* SPI-specific routines that won't be necessary for other interfaces */ > +struct regmap *ocelot_spi_init_regmap(struct device *dev, > + const struct resource *res); > + > +#define OCELOT_SPI_BYTE_ORDER_LE 0x00000000 > +#define OCELOT_SPI_BYTE_ORDER_BE 0x81818181 > + > +#ifdef __LITTLE_ENDIAN > +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_LE > +#else > +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_BE > +#endif
On Mon, Jul 18, 2022 at 03:18:28PM +0100, Lee Jones wrote: > On Tue, 05 Jul 2022, Colin Foster wrote: > > > The VSC7512 is a networking chip that contains several peripherals. Many of > > these peripherals are currently supported by the VSC7513 and VSC7514 chips, > > but those run on an internal CPU. The VSC7512 lacks this CPU, and must be > > controlled externally. > > > > Utilize the existing drivers by referencing the chip as an MFD. Add support > > for the two MDIO buses, the internal phys, pinctrl, and serial GPIO. > > > > Signed-off-by: Colin Foster <colin.foster@in-advantage.com> > > --- > > MAINTAINERS | 1 + > > drivers/mfd/Kconfig | 21 +++ > > drivers/mfd/Makefile | 3 + > > drivers/mfd/ocelot-core.c | 169 ++++++++++++++++++++ > > drivers/mfd/ocelot-spi.c | 317 ++++++++++++++++++++++++++++++++++++++ > > drivers/mfd/ocelot.h | 34 ++++ > > 6 files changed, 545 insertions(+) > > create mode 100644 drivers/mfd/ocelot-core.c > > create mode 100644 drivers/mfd/ocelot-spi.c > > create mode 100644 drivers/mfd/ocelot.h > > Generally this is looking much better. > > Almost ready for inclusion with just a few nits. > Hi Lee, Thanks for the feedback. I'll get these fixes done this week!
On Mon, Jul 18, 2022 at 03:18:28PM +0100, Lee Jones wrote: > On Tue, 05 Jul 2022, Colin Foster wrote: > > > +MODULE_IMPORT_NS(MFD_OCELOT_SPI); > > diff --git a/drivers/mfd/ocelot-spi.c b/drivers/mfd/ocelot-spi.c > > new file mode 100644 > > index 000000000000..0c1c5215c706 > > --- /dev/null > > +++ b/drivers/mfd/ocelot-spi.c > > @@ -0,0 +1,317 @@ > > +// SPDX-License-Identifier: (GPL-2.0 OR MIT) > > +/* > > + * SPI core driver for the Ocelot chip family. > > + * > > + * This driver will handle everything necessary to allow for communication over > > + * SPI to the VSC7511, VSC7512, VSC7513 and VSC7514 chips. The main functions > > + * are to prepare the chip's SPI interface for a specific bus speed, and a host > > + * processor's endianness. This will create and distribute regmaps for any > > + * children. > > + * > > + * Copyright 2021, 2022 Innovative Advantage Inc. > > + * > > + * Author: Colin Foster <colin.foster@in-advantage.com> > > + */ > > + > > +#include <linux/ioport.h> > > +#include <linux/kconfig.h> > > +#include <linux/module.h> > > +#include <linux/regmap.h> > > +#include <linux/spi/spi.h> > > + > > +#include <asm/byteorder.h> > > + > > +#include "ocelot.h" > > + > > +#define REG_DEV_CPUORG_IF_CTRL 0x0000 > > +#define REG_DEV_CPUORG_IF_CFGSTAT 0x0004 > > + > > +#define CFGSTAT_IF_NUM_VCORE (0 << 24) > > +#define CFGSTAT_IF_NUM_VRAP (1 << 24) > > +#define CFGSTAT_IF_NUM_SI (2 << 24) > > +#define CFGSTAT_IF_NUM_MIIM (3 << 24) > > + > > +#define VSC7512_DEVCPU_ORG_RES_START 0x71000000 > > +#define VSC7512_DEVCPU_ORG_RES_SIZE 0x38 > > + > > +#define VSC7512_CHIP_REGS_RES_START 0x71070000 > > +#define VSC7512_CHIP_REGS_RES_SIZE 0x14 > > + > > +struct spi_device; > > Why not just #include? I mis-understood this to mean drivers/mfd/ocelot-spi.c when it meant drivers/mfd/ocelot.h. Thanks. https://patchwork.kernel.org/project/netdevbpf/patch/20220701192609.3970317-10-colin.foster@in-advantage.com/#24921057 """ You missed a lot of forward declarations that are used in this file. Like struct spi_device; """ > > +static int ocelot_spi_regmap_bus_read(void *context, > > + const void *reg, size_t reg_size, > > + void *val, size_t val_size) > > +{ > > + struct ocelot_ddata *ddata = context; > > + struct spi_transfer tx, padding, rx; > > + struct spi_device *spi = ddata->spi; > > + struct spi_message msg; > > + > > + spi = ddata->spi; > > Drop this line. Yes - and actually since I'm removing ddata->spi altogether it'll become to_spi_device(ddata->dev) (obviously without the double-assignment that you're pointing out here) > > > + spi_message_init(&msg); > > + > > + memset(&tx, 0, sizeof(tx)); > > + > > + tx.tx_buf = reg; > > + tx.len = reg_size; > > + > > + spi_message_add_tail(&tx, &msg); > > + > > + if (ddata->spi_padding_bytes) { > > + memset(&padding, 0, sizeof(padding)); > > + > > + padding.len = ddata->spi_padding_bytes; > > + padding.tx_buf = ddata->dummy_buf; > > + padding.dummy_data = 1; > > + > > + spi_message_add_tail(&padding, &msg); > > + } > > + > > + memset(&rx, 0, sizeof(rx)); > > + rx.rx_buf = val; > > + rx.len = val_size; > > + > > + spi_message_add_tail(&rx, &msg); > > + > > + return spi_sync(spi, &msg); > > +} > > + > > +static int ocelot_spi_regmap_bus_write(void *context, const void *data, > > + size_t count) > > +{ > > + struct ocelot_ddata *ddata = context; > > + struct spi_device *spi = ddata->spi; As above, I'm changing to to_spi_device(ddata->dev) > > + > > + return spi_write(spi, data, count); > > +} > > + > > +static const struct regmap_bus ocelot_spi_regmap_bus = { > > + .write = ocelot_spi_regmap_bus_write, > > + .read = ocelot_spi_regmap_bus_read, > > +}; > > + > > +struct regmap * > > +ocelot_spi_init_regmap(struct device *dev, const struct resource *res) > > One line, along with all the others. > > > +{ > > + struct ocelot_ddata *ddata = dev_get_drvdata(dev); > > + struct regmap_config regmap_config; > > + > > + memcpy(®map_config, &ocelot_spi_regmap_config, > > + sizeof(regmap_config)); > > + > > + regmap_config.name = res->name; > > + regmap_config.max_register = res->end - res->start; > > + regmap_config.reg_base = res->start; > > + > > + return devm_regmap_init(dev, &ocelot_spi_regmap_bus, ddata, > > + ®map_config); > > +} > > +EXPORT_SYMBOL_NS(ocelot_spi_init_regmap, MFD_OCELOT_SPI); > > + > > +static int ocelot_spi_probe(struct spi_device *spi) > > +{ > > + struct device *dev = &spi->dev; > > + struct ocelot_ddata *ddata; > > + struct regmap *r; > > + int err; > > + > > + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); > > + if (!ddata) > > + return -ENOMEM; > > + > > + ddata->dev = dev; > > How are you fetching ddata if you don't already have 'dev'? I don't think I fully understand this question... Are you saying ddata doesn't need a dev instance? So instead of: devm_regmap_init(dev, &bus, ddata, ®map_config); It could be: devm_regmap_init(dev, &bus, dev, ®map_config); In that case, the context into ocelot_spi_regmap_bus_{read,write} would be dev, instead of ddata. Then I get ddata from device via: static int ocelot_spi_regmap_bus_write(void *context,...) { struct device *dev = context; struct ocelot_ddata *ddata = dev_get_drvdata(dev); struct spi_device *spi = to_spi_device(dev); /* ddata isn't actually needed for bus_write, just making a point */ ... } I haven't tested this yet, but I think this is what you're suggesting. So now I've removed both spi and dev from the ddata struct (as I mention below). Cool. > > > + dev_set_drvdata(dev, ddata); > > This should use the spi_* variant. Agreed. > > > + if (spi->max_speed_hz <= 500000) { > > + ddata->spi_padding_bytes = 0; > > + } else { > > + /* > > + * Calculation taken from the manual for IF_CFGSTAT:IF_CFG. > > + * Register access time is 1us, so we need to configure and send > > + * out enough padding bytes between the read request and data > > + * transmission that lasts at least 1 microsecond. > > + */ > > + ddata->spi_padding_bytes = 1 + > > + (spi->max_speed_hz / 1000000 + 2) / 8; > > + > > + ddata->dummy_buf = devm_kzalloc(dev, ddata->spi_padding_bytes, > > + GFP_KERNEL); > > + if (!ddata->dummy_buf) > > + return -ENOMEM; > > + } > > + > > + ddata->spi = spi; > > If you have 'spi' you definitely do not need 'dev'. > > You can derive one from the other. Good point. As I implied above, I'm dropping "spi" from the ddata struct and will recover spi from to_spi_device(dev) That does some nice things like removes "struct spi_device" from drivers/mfd/ocelot.h > > + spi->bits_per_word = 8; > > + > > + err = spi_setup(spi); > > + if (err < 0) > > + return dev_err_probe(&spi->dev, err, > > + "Error performing SPI setup\n"); > > + > > + r = ocelot_spi_init_regmap(dev, &vsc7512_dev_cpuorg_resource); > > + if (IS_ERR(r)) > > + return PTR_ERR(r); > > + > > + ddata->cpuorg_regmap = r; > > + > > + r = ocelot_spi_init_regmap(dev, &vsc7512_gcb_resource); > > + if (IS_ERR(r)) > > + return PTR_ERR(r); > > + > > + ddata->gcb_regmap = r; > > + > > + /* > > + * The chip must be set up for SPI before it gets initialized and reset. > > + * This must be done before calling init, and after a chip reset is > > + * performed. > > + */ > > + err = ocelot_spi_initialize(dev); > > + if (err) > > + return dev_err_probe(dev, err, "Error initializing SPI bus\n"); > > + > > + err = ocelot_chip_reset(dev); > > + if (err) > > + return dev_err_probe(dev, err, "Error resetting device\n"); > > + > > + /* > > + * A chip reset will clear the SPI configuration, so it needs to be done > > + * again before we can access any registers > > + */ > > + err = ocelot_spi_initialize(dev); > > + if (err) > > + return dev_err_probe(dev, err, > > + "Error initializing SPI bus after reset\n"); > > + > > + err = ocelot_core_init(dev); > > + if (err < 0) > > + return dev_err_probe(dev, err, > > + "Error initializing Ocelot core\n"); > > + > > + return 0; > > +} > > + > > +static const struct spi_device_id ocelot_spi_ids[] = { > > + { "vsc7512", 0 }, > > + { } > > +}; > > + > > +static const struct of_device_id ocelot_spi_of_match[] = { > > + { .compatible = "mscc,vsc7512" }, > > + { } > > +}; > > +MODULE_DEVICE_TABLE(of, ocelot_spi_of_match); > > + > > +static struct spi_driver ocelot_spi_driver = { > > + .driver = { > > + .name = "ocelot-soc", > > + .of_match_table = ocelot_spi_of_match, > > + }, > > + .id_table = ocelot_spi_ids, > > + .probe = ocelot_spi_probe, > > +}; > > +module_spi_driver(ocelot_spi_driver); > > + > > +MODULE_DESCRIPTION("SPI Controlled Ocelot Chip Driver"); > > +MODULE_AUTHOR("Colin Foster <colin.foster@in-advantage.com>"); > > +MODULE_LICENSE("Dual MIT/GPL"); > > +MODULE_IMPORT_NS(MFD_OCELOT); > > diff --git a/drivers/mfd/ocelot.h b/drivers/mfd/ocelot.h > > new file mode 100644 > > index 000000000000..c86bd6990a3c > > --- /dev/null > > +++ b/drivers/mfd/ocelot.h > > @@ -0,0 +1,34 @@ > > +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ > > +/* Copyright 2021, 2022 Innovative Advantage Inc. */ > > + > > +#include <asm/byteorder.h> > > + > > +struct device; > > +struct spi_device; > > +struct regmap; > > +struct resource; > > + > > +struct ocelot_ddata { > > + struct device *dev; > > + struct regmap *gcb_regmap; > > + struct regmap *cpuorg_regmap; > > + int spi_padding_bytes; > > + struct spi_device *spi; > > + void *dummy_buf; > > +}; > > This looks like it deserves a doc header. Will do! > > > +int ocelot_chip_reset(struct device *dev); > > +int ocelot_core_init(struct device *dev); > > + > > +/* SPI-specific routines that won't be necessary for other interfaces */ > > +struct regmap *ocelot_spi_init_regmap(struct device *dev, > > + const struct resource *res); > > + > > +#define OCELOT_SPI_BYTE_ORDER_LE 0x00000000 > > +#define OCELOT_SPI_BYTE_ORDER_BE 0x81818181 > > + > > +#ifdef __LITTLE_ENDIAN > > +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_LE > > +#else > > +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_BE > > +#endif > > -- > Lee Jones [李琼斯] > Principal Technical Lead - Developer Services > Linaro.org │ Open source software for Arm SoCs > Follow Linaro: Facebook | Twitter | Blog
On Tue, 19 Jul 2022, Colin Foster wrote: > On Mon, Jul 18, 2022 at 03:18:28PM +0100, Lee Jones wrote: > > On Tue, 05 Jul 2022, Colin Foster wrote: > > > > > +MODULE_IMPORT_NS(MFD_OCELOT_SPI); > > > diff --git a/drivers/mfd/ocelot-spi.c b/drivers/mfd/ocelot-spi.c > > > new file mode 100644 > > > index 000000000000..0c1c5215c706 > > > --- /dev/null > > > +++ b/drivers/mfd/ocelot-spi.c > > > @@ -0,0 +1,317 @@ > > > +// SPDX-License-Identifier: (GPL-2.0 OR MIT) > > > +/* > > > + * SPI core driver for the Ocelot chip family. > > > + * > > > + * This driver will handle everything necessary to allow for communication over > > > + * SPI to the VSC7511, VSC7512, VSC7513 and VSC7514 chips. The main functions > > > + * are to prepare the chip's SPI interface for a specific bus speed, and a host > > > + * processor's endianness. This will create and distribute regmaps for any > > > + * children. > > > + * > > > + * Copyright 2021, 2022 Innovative Advantage Inc. > > > + * > > > + * Author: Colin Foster <colin.foster@in-advantage.com> > > > + */ > > > + > > > +#include <linux/ioport.h> > > > +#include <linux/kconfig.h> > > > +#include <linux/module.h> > > > +#include <linux/regmap.h> > > > +#include <linux/spi/spi.h> > > > + > > > +#include <asm/byteorder.h> > > > + > > > +#include "ocelot.h" > > > + > > > +#define REG_DEV_CPUORG_IF_CTRL 0x0000 > > > +#define REG_DEV_CPUORG_IF_CFGSTAT 0x0004 > > > + > > > +#define CFGSTAT_IF_NUM_VCORE (0 << 24) > > > +#define CFGSTAT_IF_NUM_VRAP (1 << 24) > > > +#define CFGSTAT_IF_NUM_SI (2 << 24) > > > +#define CFGSTAT_IF_NUM_MIIM (3 << 24) > > > + > > > +#define VSC7512_DEVCPU_ORG_RES_START 0x71000000 > > > +#define VSC7512_DEVCPU_ORG_RES_SIZE 0x38 > > > + > > > +#define VSC7512_CHIP_REGS_RES_START 0x71070000 > > > +#define VSC7512_CHIP_REGS_RES_SIZE 0x14 > > > + > > > +struct spi_device; > > > > Why not just #include? > > I mis-understood this to mean drivers/mfd/ocelot-spi.c when it meant > drivers/mfd/ocelot.h. Thanks. > > https://patchwork.kernel.org/project/netdevbpf/patch/20220701192609.3970317-10-colin.foster@in-advantage.com/#24921057 > > """ > You missed a lot of forward declarations that are used in this file. > > Like > > struct spi_device; > """ spi_device is used in *this* file. You should explicitly add the include file.
diff --git a/MAINTAINERS b/MAINTAINERS index 5e798c42fa08..e3299677cd4a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14471,6 +14471,7 @@ OCELOT EXTERNAL SWITCH CONTROL M: Colin Foster <colin.foster@in-advantage.com> S: Supported F: Documentation/devicetree/bindings/mfd/mscc,ocelot.yaml +F: drivers/mfd/ocelot* F: include/linux/mfd/ocelot.h OCXL (Open Coherent Accelerator Processor Interface OpenCAPI) DRIVER diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 3b59456f5545..0ef433d170dc 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -962,6 +962,27 @@ config MFD_MENF21BMC This driver can also be built as a module. If so the module will be called menf21bmc. +config MFD_OCELOT + tristate "Microsemi Ocelot External Control Support" + depends on SPI_MASTER + select MFD_CORE + select REGMAP_SPI + help + Ocelot is a family of networking chips that support multiple ethernet + and fibre interfaces. In addition to networking, they contain several + other functions, including pinctrl, MDIO, and communication with + external chips. While some chips have an internal processor capable of + running an OS, others don't. All chips can be controlled externally + through different interfaces, including SPI, I2C, and PCIe. + + Say yes here to add support for Ocelot chips (VSC7511, VSC7512, + VSC7513, VSC7514) controlled externally. + + To compile this driver as a module, choose M here: the module will be + called ocelot-soc. + + If unsure, say N. + config EZX_PCAP bool "Motorola EZXPCAP Support" depends on SPI_MASTER diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index 858cacf659d6..0004b7e86220 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -120,6 +120,9 @@ obj-$(CONFIG_MFD_MC13XXX_I2C) += mc13xxx-i2c.o obj-$(CONFIG_MFD_CORE) += mfd-core.o +ocelot-soc-objs := ocelot-core.o ocelot-spi.o +obj-$(CONFIG_MFD_OCELOT) += ocelot-soc.o + obj-$(CONFIG_EZX_PCAP) += ezx-pcap.o obj-$(CONFIG_MFD_CPCAP) += motorola-cpcap.o diff --git a/drivers/mfd/ocelot-core.c b/drivers/mfd/ocelot-core.c new file mode 100644 index 000000000000..e07cd901e1b3 --- /dev/null +++ b/drivers/mfd/ocelot-core.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: (GPL-2.0 OR MIT) +/* + * Core driver for the Ocelot chip family. + * + * The VSC7511, 7512, 7513, and 7514 can be controlled internally via an + * on-chip MIPS processor, or externally via SPI, I2C, PCIe. This core driver is + * intended to be the bus-agnostic glue between, for example, the SPI bus and + * the child devices. + * + * Copyright 2021, 2022 Innovative Advantage Inc. + * + * Author: Colin Foster <colin.foster@in-advantage.com> + */ + +#include <linux/kernel.h> +#include <linux/mfd/core.h> +#include <linux/mfd/ocelot.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/types.h> + +#include <soc/mscc/ocelot.h> + +#include "ocelot.h" + +#define REG_GCB_SOFT_RST 0x0008 + +#define BIT_SOFT_CHIP_RST BIT(0) + +#define VSC7512_MIIM0_RES_START 0x7107009c +#define VSC7512_MIIM0_RES_SIZE 0x24 + +#define VSC7512_MIIM1_RES_START 0x710700c0 +#define VSC7512_MIIM1_RES_SIZE 0x24 + +#define VSC7512_PHY_RES_START 0x710700f0 +#define VSC7512_PHY_RES_SIZE 0x4 + +#define VSC7512_GPIO_RES_START 0x71070034 +#define VSC7512_GPIO_RES_SIZE 0x6c + +#define VSC7512_SIO_CTRL_RES_START 0x710700f8 +#define VSC7512_SIO_CTRL_RES_SIZE 0x100 + +#define VSC7512_GCB_RST_SLEEP_US 100 +#define VSC7512_GCB_RST_TIMEOUT_US 100000 + +static int ocelot_gcb_chip_rst_status(struct ocelot_ddata *ddata) +{ + int val, err; + + err = regmap_read(ddata->gcb_regmap, REG_GCB_SOFT_RST, &val); + if (err) + val = err; + + return val; +} + +int ocelot_chip_reset(struct device *dev) +{ + struct ocelot_ddata *ddata = dev_get_drvdata(dev); + int ret, val; + + /* + * Reset the entire chip here to put it into a completely known state. + * Other drivers may want to reset their own subsystems. The register + * self-clears, so one write is all that is needed and wait for it to + * clear. + */ + ret = regmap_write(ddata->gcb_regmap, REG_GCB_SOFT_RST, + BIT_SOFT_CHIP_RST); + if (ret) + return ret; + + ret = readx_poll_timeout(ocelot_gcb_chip_rst_status, ddata, val, !val, + VSC7512_GCB_RST_SLEEP_US, + VSC7512_GCB_RST_TIMEOUT_US); + if (ret) + return dev_err_probe(ddata->dev, ret, "timeout: chip reset\n"); + + return 0; +} +EXPORT_SYMBOL_NS(ocelot_chip_reset, MFD_OCELOT); + +static const struct resource vsc7512_miim0_resources[] = { + DEFINE_RES_REG_NAMED(VSC7512_MIIM0_RES_START, VSC7512_MIIM0_RES_SIZE, + "gcb_miim0"), + DEFINE_RES_REG_NAMED(VSC7512_PHY_RES_START, VSC7512_PHY_RES_SIZE, + "gcb_phy"), +}; + +static const struct resource vsc7512_miim1_resources[] = { + DEFINE_RES_REG_NAMED(VSC7512_MIIM1_RES_START, VSC7512_MIIM1_RES_SIZE, + "gcb_miim1"), +}; + +static const struct resource vsc7512_pinctrl_resources[] = { + DEFINE_RES_REG_NAMED(VSC7512_GPIO_RES_START, VSC7512_GPIO_RES_SIZE, + "gcb_gpio"), +}; + +static const struct resource vsc7512_sgpio_resources[] = { + DEFINE_RES_REG_NAMED(VSC7512_SIO_CTRL_RES_START, + VSC7512_SIO_CTRL_RES_SIZE, + "gcb_sio"), +}; + +static const struct mfd_cell vsc7512_devs[] = { + { + .name = "ocelot-pinctrl", + .of_compatible = "mscc,ocelot-pinctrl", + .num_resources = ARRAY_SIZE(vsc7512_pinctrl_resources), + .resources = vsc7512_pinctrl_resources, + }, { + .name = "ocelot-sgpio", + .of_compatible = "mscc,ocelot-sgpio", + .num_resources = ARRAY_SIZE(vsc7512_sgpio_resources), + .resources = vsc7512_sgpio_resources, + }, { + .name = "ocelot-miim0", + .of_compatible = "mscc,ocelot-miim", + .of_reg = VSC7512_MIIM0_RES_START, + .use_of_reg = true, + .num_resources = ARRAY_SIZE(vsc7512_miim0_resources), + .resources = vsc7512_miim0_resources, + }, { + .name = "ocelot-miim1", + .of_compatible = "mscc,ocelot-miim", + .of_reg = VSC7512_MIIM1_RES_START, + .use_of_reg = true, + .num_resources = ARRAY_SIZE(vsc7512_miim1_resources), + .resources = vsc7512_miim1_resources, + }, +}; + +static void ocelot_core_try_add_regmap(struct device *dev, + const struct resource *res) +{ + if (!dev_get_regmap(dev, res->name)) + ocelot_spi_init_regmap(dev, res); +} + +static void ocelot_core_try_add_regmaps(struct device *dev, + const struct mfd_cell *cell) +{ + int i; + + for (i = 0; i < cell->num_resources; i++) + ocelot_core_try_add_regmap(dev, &cell->resources[i]); +} + +int ocelot_core_init(struct device *dev) +{ + int i, ndevs; + + ndevs = ARRAY_SIZE(vsc7512_devs); + + for (i = 0; i < ndevs; i++) + ocelot_core_try_add_regmaps(dev, &vsc7512_devs[i]); + + return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, vsc7512_devs, + ndevs, NULL, 0, NULL); +} +EXPORT_SYMBOL_NS(ocelot_core_init, MFD_OCELOT); + +MODULE_DESCRIPTION("Externally Controlled Ocelot Chip Driver"); +MODULE_AUTHOR("Colin Foster <colin.foster@in-advantage.com>"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(MFD_OCELOT_SPI); diff --git a/drivers/mfd/ocelot-spi.c b/drivers/mfd/ocelot-spi.c new file mode 100644 index 000000000000..0c1c5215c706 --- /dev/null +++ b/drivers/mfd/ocelot-spi.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: (GPL-2.0 OR MIT) +/* + * SPI core driver for the Ocelot chip family. + * + * This driver will handle everything necessary to allow for communication over + * SPI to the VSC7511, VSC7512, VSC7513 and VSC7514 chips. The main functions + * are to prepare the chip's SPI interface for a specific bus speed, and a host + * processor's endianness. This will create and distribute regmaps for any + * children. + * + * Copyright 2021, 2022 Innovative Advantage Inc. + * + * Author: Colin Foster <colin.foster@in-advantage.com> + */ + +#include <linux/ioport.h> +#include <linux/kconfig.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> + +#include <asm/byteorder.h> + +#include "ocelot.h" + +#define REG_DEV_CPUORG_IF_CTRL 0x0000 +#define REG_DEV_CPUORG_IF_CFGSTAT 0x0004 + +#define CFGSTAT_IF_NUM_VCORE (0 << 24) +#define CFGSTAT_IF_NUM_VRAP (1 << 24) +#define CFGSTAT_IF_NUM_SI (2 << 24) +#define CFGSTAT_IF_NUM_MIIM (3 << 24) + +#define VSC7512_DEVCPU_ORG_RES_START 0x71000000 +#define VSC7512_DEVCPU_ORG_RES_SIZE 0x38 + +#define VSC7512_CHIP_REGS_RES_START 0x71070000 +#define VSC7512_CHIP_REGS_RES_SIZE 0x14 + +struct spi_device; + +static const struct resource vsc7512_dev_cpuorg_resource = + DEFINE_RES_REG_NAMED(VSC7512_DEVCPU_ORG_RES_START, + VSC7512_DEVCPU_ORG_RES_SIZE, + "devcpu_org"); + +static const struct resource vsc7512_gcb_resource = + DEFINE_RES_REG_NAMED(VSC7512_CHIP_REGS_RES_START, + VSC7512_CHIP_REGS_RES_SIZE, + "devcpu_gcb_chip_regs"); + +static int ocelot_spi_initialize(struct device *dev) +{ + struct ocelot_ddata *ddata = dev_get_drvdata(dev); + u32 val, check; + int err; + + val = OCELOT_SPI_BYTE_ORDER; + + /* + * The SPI address must be big-endian, but we want the payload to match + * our CPU. These are two bits (0 and 1) but they're repeated such that + * the write from any configuration will be valid. The four + * configurations are: + * + * 0b00: little-endian, MSB first + * | 111111 | 22221111 | 33222222 | + * | 76543210 | 54321098 | 32109876 | 10987654 | + * + * 0b01: big-endian, MSB first + * | 33222222 | 22221111 | 111111 | | + * | 10987654 | 32109876 | 54321098 | 76543210 | + * + * 0b10: little-endian, LSB first + * | 111111 | 11112222 | 22222233 | + * | 01234567 | 89012345 | 67890123 | 45678901 | + * + * 0b11: big-endian, LSB first + * | 22222233 | 11112222 | 111111 | | + * | 45678901 | 67890123 | 89012345 | 01234567 | + */ + err = regmap_write(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CTRL, val); + if (err) + return err; + + /* + * Apply the number of padding bytes between a read request and the data + * payload. Some registers have access times of up to 1us, so if the + * first payload bit is shifted out too quickly, the read will fail. + */ + val = ddata->spi_padding_bytes; + err = regmap_write(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CFGSTAT, + val); + if (err) + return err; + + /* + * After we write the interface configuration, read it back here. This + * will verify several different things. The first is that the number of + * padding bytes actually got written correctly. These are found in bits + * 0:3. + * + * The second is that bit 16 is cleared. Bit 16 is IF_CFGSTAT:IF_STAT, + * and will be set if the register access is too fast. This would be in + * the condition that the number of padding bytes is insufficient for + * the SPI bus frequency. + * + * The last check is for bits 31:24, which define the interface by which + * the registers are being accessed. Since we're accessing them via the + * serial interface, it must return IF_NUM_SI. + */ + check = val | CFGSTAT_IF_NUM_SI; + + err = regmap_read(ddata->cpuorg_regmap, REG_DEV_CPUORG_IF_CFGSTAT, + &val); + if (err) + return err; + + if (check != val) + return -ENODEV; + + return 0; +} + +static const struct regmap_config ocelot_spi_regmap_config = { + .reg_bits = 24, + .reg_stride = 4, + .reg_downshift = 2, + .val_bits = 32, + + .write_flag_mask = 0x80, + + .use_single_write = true, + .can_multi_write = false, + + .reg_format_endian = REGMAP_ENDIAN_BIG, + .val_format_endian = REGMAP_ENDIAN_NATIVE, +}; + +static int ocelot_spi_regmap_bus_read(void *context, + const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct ocelot_ddata *ddata = context; + struct spi_transfer tx, padding, rx; + struct spi_device *spi = ddata->spi; + struct spi_message msg; + + spi = ddata->spi; + + spi_message_init(&msg); + + memset(&tx, 0, sizeof(tx)); + + tx.tx_buf = reg; + tx.len = reg_size; + + spi_message_add_tail(&tx, &msg); + + if (ddata->spi_padding_bytes) { + memset(&padding, 0, sizeof(padding)); + + padding.len = ddata->spi_padding_bytes; + padding.tx_buf = ddata->dummy_buf; + padding.dummy_data = 1; + + spi_message_add_tail(&padding, &msg); + } + + memset(&rx, 0, sizeof(rx)); + rx.rx_buf = val; + rx.len = val_size; + + spi_message_add_tail(&rx, &msg); + + return spi_sync(spi, &msg); +} + +static int ocelot_spi_regmap_bus_write(void *context, const void *data, + size_t count) +{ + struct ocelot_ddata *ddata = context; + struct spi_device *spi = ddata->spi; + + return spi_write(spi, data, count); +} + +static const struct regmap_bus ocelot_spi_regmap_bus = { + .write = ocelot_spi_regmap_bus_write, + .read = ocelot_spi_regmap_bus_read, +}; + +struct regmap * +ocelot_spi_init_regmap(struct device *dev, const struct resource *res) +{ + struct ocelot_ddata *ddata = dev_get_drvdata(dev); + struct regmap_config regmap_config; + + memcpy(®map_config, &ocelot_spi_regmap_config, + sizeof(regmap_config)); + + regmap_config.name = res->name; + regmap_config.max_register = res->end - res->start; + regmap_config.reg_base = res->start; + + return devm_regmap_init(dev, &ocelot_spi_regmap_bus, ddata, + ®map_config); +} +EXPORT_SYMBOL_NS(ocelot_spi_init_regmap, MFD_OCELOT_SPI); + +static int ocelot_spi_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct ocelot_ddata *ddata; + struct regmap *r; + int err; + + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL); + if (!ddata) + return -ENOMEM; + + ddata->dev = dev; + dev_set_drvdata(dev, ddata); + + if (spi->max_speed_hz <= 500000) { + ddata->spi_padding_bytes = 0; + } else { + /* + * Calculation taken from the manual for IF_CFGSTAT:IF_CFG. + * Register access time is 1us, so we need to configure and send + * out enough padding bytes between the read request and data + * transmission that lasts at least 1 microsecond. + */ + ddata->spi_padding_bytes = 1 + + (spi->max_speed_hz / 1000000 + 2) / 8; + + ddata->dummy_buf = devm_kzalloc(dev, ddata->spi_padding_bytes, + GFP_KERNEL); + if (!ddata->dummy_buf) + return -ENOMEM; + } + + ddata->spi = spi; + spi->bits_per_word = 8; + + err = spi_setup(spi); + if (err < 0) + return dev_err_probe(&spi->dev, err, + "Error performing SPI setup\n"); + + r = ocelot_spi_init_regmap(dev, &vsc7512_dev_cpuorg_resource); + if (IS_ERR(r)) + return PTR_ERR(r); + + ddata->cpuorg_regmap = r; + + r = ocelot_spi_init_regmap(dev, &vsc7512_gcb_resource); + if (IS_ERR(r)) + return PTR_ERR(r); + + ddata->gcb_regmap = r; + + /* + * The chip must be set up for SPI before it gets initialized and reset. + * This must be done before calling init, and after a chip reset is + * performed. + */ + err = ocelot_spi_initialize(dev); + if (err) + return dev_err_probe(dev, err, "Error initializing SPI bus\n"); + + err = ocelot_chip_reset(dev); + if (err) + return dev_err_probe(dev, err, "Error resetting device\n"); + + /* + * A chip reset will clear the SPI configuration, so it needs to be done + * again before we can access any registers + */ + err = ocelot_spi_initialize(dev); + if (err) + return dev_err_probe(dev, err, + "Error initializing SPI bus after reset\n"); + + err = ocelot_core_init(dev); + if (err < 0) + return dev_err_probe(dev, err, + "Error initializing Ocelot core\n"); + + return 0; +} + +static const struct spi_device_id ocelot_spi_ids[] = { + { "vsc7512", 0 }, + { } +}; + +static const struct of_device_id ocelot_spi_of_match[] = { + { .compatible = "mscc,vsc7512" }, + { } +}; +MODULE_DEVICE_TABLE(of, ocelot_spi_of_match); + +static struct spi_driver ocelot_spi_driver = { + .driver = { + .name = "ocelot-soc", + .of_match_table = ocelot_spi_of_match, + }, + .id_table = ocelot_spi_ids, + .probe = ocelot_spi_probe, +}; +module_spi_driver(ocelot_spi_driver); + +MODULE_DESCRIPTION("SPI Controlled Ocelot Chip Driver"); +MODULE_AUTHOR("Colin Foster <colin.foster@in-advantage.com>"); +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_IMPORT_NS(MFD_OCELOT); diff --git a/drivers/mfd/ocelot.h b/drivers/mfd/ocelot.h new file mode 100644 index 000000000000..c86bd6990a3c --- /dev/null +++ b/drivers/mfd/ocelot.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0 OR MIT */ +/* Copyright 2021, 2022 Innovative Advantage Inc. */ + +#include <asm/byteorder.h> + +struct device; +struct spi_device; +struct regmap; +struct resource; + +struct ocelot_ddata { + struct device *dev; + struct regmap *gcb_regmap; + struct regmap *cpuorg_regmap; + int spi_padding_bytes; + struct spi_device *spi; + void *dummy_buf; +}; + +int ocelot_chip_reset(struct device *dev); +int ocelot_core_init(struct device *dev); + +/* SPI-specific routines that won't be necessary for other interfaces */ +struct regmap *ocelot_spi_init_regmap(struct device *dev, + const struct resource *res); + +#define OCELOT_SPI_BYTE_ORDER_LE 0x00000000 +#define OCELOT_SPI_BYTE_ORDER_BE 0x81818181 + +#ifdef __LITTLE_ENDIAN +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_LE +#else +#define OCELOT_SPI_BYTE_ORDER OCELOT_SPI_BYTE_ORDER_BE +#endif
The VSC7512 is a networking chip that contains several peripherals. Many of these peripherals are currently supported by the VSC7513 and VSC7514 chips, but those run on an internal CPU. The VSC7512 lacks this CPU, and must be controlled externally. Utilize the existing drivers by referencing the chip as an MFD. Add support for the two MDIO buses, the internal phys, pinctrl, and serial GPIO. Signed-off-by: Colin Foster <colin.foster@in-advantage.com> --- MAINTAINERS | 1 + drivers/mfd/Kconfig | 21 +++ drivers/mfd/Makefile | 3 + drivers/mfd/ocelot-core.c | 169 ++++++++++++++++++++ drivers/mfd/ocelot-spi.c | 317 ++++++++++++++++++++++++++++++++++++++ drivers/mfd/ocelot.h | 34 ++++ 6 files changed, 545 insertions(+) create mode 100644 drivers/mfd/ocelot-core.c create mode 100644 drivers/mfd/ocelot-spi.c create mode 100644 drivers/mfd/ocelot.h