diff --git a/MAINTAINERS b/MAINTAINERS index c291fe45e191..6c2315c1297c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17118,6 +17118,8 @@ M: Parthiban Veerasooran L: netdev@vger.kernel.org S: Maintained F: Documentation/networking/oa-tc6-framework.rst +F: drivers/include/linux/oa_tc6.h +F: drivers/net/ethernet/oa_tc6.c OPEN FIRMWARE AND FLATTENED DEVICE TREE M: Rob Herring diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig index 0baac25db4f8..9a542e3c9b05 100644 --- a/drivers/net/ethernet/Kconfig +++ b/drivers/net/ethernet/Kconfig @@ -158,6 +158,17 @@ config ETHOC help Say Y here if you want to use the OpenCores 10/100 Mbps Ethernet MAC. +config OA_TC6 + tristate "OPEN Alliance TC6 10BASE-T1x MAC-PHY support" + depends on SPI + select PHYLIB + help + This library implements OPEN Alliance TC6 10BASE-T1x MAC-PHY + Serial Interface protocol for supporting 10BASE-T1x MAC-PHYs. + + To know the implementation details, refer documentation in + . + source "drivers/net/ethernet/packetengines/Kconfig" source "drivers/net/ethernet/pasemi/Kconfig" source "drivers/net/ethernet/pensando/Kconfig" diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile index c03203439c0e..99fa180dedb8 100644 --- a/drivers/net/ethernet/Makefile +++ b/drivers/net/ethernet/Makefile @@ -105,3 +105,4 @@ obj-$(CONFIG_NET_VENDOR_XILINX) += xilinx/ obj-$(CONFIG_NET_VENDOR_XIRCOM) += xircom/ obj-$(CONFIG_NET_VENDOR_SYNOPSYS) += synopsys/ obj-$(CONFIG_NET_VENDOR_PENSANDO) += pensando/ +obj-$(CONFIG_OA_TC6) += oa_tc6.o diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c new file mode 100644 index 000000000000..24e9fd92d717 --- /dev/null +++ b/drivers/net/ethernet/oa_tc6.c @@ -0,0 +1,242 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface framework + * + * Author: Parthiban Veerasooran + */ + +#include +#include + +/* Control command header */ +#define OA_TC6_CTRL_HEADER_DATA_NOT_CTRL BIT(31) +#define OA_TC6_CTRL_HEADER_WRITE_NOT_READ BIT(29) +#define OA_TC6_CTRL_HEADER_MEM_MAP_SELECTOR GENMASK(27, 24) +#define OA_TC6_CTRL_HEADER_ADDR GENMASK(23, 8) +#define OA_TC6_CTRL_HEADER_LENGTH GENMASK(7, 1) +#define OA_TC6_CTRL_HEADER_PARITY BIT(0) + +#define OA_TC6_CTRL_HEADER_SIZE 4 +#define OA_TC6_CTRL_REG_VALUE_SIZE 4 +#define OA_TC6_CTRL_IGNORED_SIZE 4 +#define OA_TC6_CTRL_MAX_REGISTERS 128 +#define OA_TC6_CTRL_SPI_BUF_SIZE (OA_TC6_CTRL_HEADER_SIZE +\ + (OA_TC6_CTRL_MAX_REGISTERS *\ + OA_TC6_CTRL_REG_VALUE_SIZE) +\ + OA_TC6_CTRL_IGNORED_SIZE) + +/* Internal structure for MAC-PHY drivers */ +struct oa_tc6 { + struct spi_device *spi; + struct mutex spi_ctrl_lock; /* Protects spi control transfer */ + void *spi_ctrl_tx_buf; + void *spi_ctrl_rx_buf; +}; + +enum oa_tc6_header_type { + OA_TC6_CTRL_HEADER, +}; + +enum oa_tc6_register_op { + OA_TC6_CTRL_REG_WRITE = 1, +}; + +static int oa_tc6_spi_transfer(struct oa_tc6 *tc6, + enum oa_tc6_header_type header_type, u16 length) +{ + struct spi_transfer xfer = { 0 }; + struct spi_message msg; + + xfer.tx_buf = tc6->spi_ctrl_tx_buf; + xfer.rx_buf = tc6->spi_ctrl_rx_buf; + xfer.len = length; + + spi_message_init(&msg); + spi_message_add_tail(&xfer, &msg); + + return spi_sync(tc6->spi, &msg); +} + +static int oa_tc6_get_parity(u32 p) +{ + /* Public domain code snippet, lifted from + * http://www-graphics.stanford.edu/~seander/bithacks.html + */ + p ^= p >> 1; + p ^= p >> 2; + p = (p & 0x11111111U) * 0x11111111U; + + /* Odd parity is used here */ + return !((p >> 28) & 1); +} + +static __be32 oa_tc6_prepare_ctrl_header(u32 addr, u8 length, + enum oa_tc6_register_op reg_op) +{ + u32 header; + + header = FIELD_PREP(OA_TC6_CTRL_HEADER_DATA_NOT_CTRL, + OA_TC6_CTRL_HEADER) | + FIELD_PREP(OA_TC6_CTRL_HEADER_WRITE_NOT_READ, reg_op) | + FIELD_PREP(OA_TC6_CTRL_HEADER_MEM_MAP_SELECTOR, addr >> 16) | + FIELD_PREP(OA_TC6_CTRL_HEADER_ADDR, addr) | + FIELD_PREP(OA_TC6_CTRL_HEADER_LENGTH, length - 1); + header |= FIELD_PREP(OA_TC6_CTRL_HEADER_PARITY, + oa_tc6_get_parity(header)); + + return cpu_to_be32(header); +} + +static void oa_tc6_update_ctrl_write_data(struct oa_tc6 *tc6, u32 value[], + u8 length) +{ + __be32 *tx_buf = tc6->spi_ctrl_tx_buf + OA_TC6_CTRL_HEADER_SIZE; + + for (int i = 0; i < length; i++) + *tx_buf++ = cpu_to_be32(value[i]); +} + +static u16 oa_tc6_calculate_ctrl_buf_size(u8 length) +{ + /* Control command consists 4 bytes header + 4 bytes register value for + * each register + 4 bytes ignored value. + */ + return OA_TC6_CTRL_HEADER_SIZE + OA_TC6_CTRL_REG_VALUE_SIZE * length + + OA_TC6_CTRL_IGNORED_SIZE; +} + +static void oa_tc6_prepare_ctrl_spi_buf(struct oa_tc6 *tc6, u32 address, + u32 value[], u8 length, + enum oa_tc6_register_op reg_op) +{ + __be32 *tx_buf = tc6->spi_ctrl_tx_buf; + + *tx_buf = oa_tc6_prepare_ctrl_header(address, length, reg_op); + + oa_tc6_update_ctrl_write_data(tc6, value, length); +} + +static int oa_tc6_check_ctrl_write_reply(struct oa_tc6 *tc6, u8 size) +{ + u8 *tx_buf = tc6->spi_ctrl_tx_buf; + u8 *rx_buf = tc6->spi_ctrl_rx_buf; + + rx_buf += OA_TC6_CTRL_IGNORED_SIZE; + + /* The echoed control write must match with the one that was + * transmitted. + */ + if (memcmp(tx_buf, rx_buf, size - OA_TC6_CTRL_IGNORED_SIZE)) + return -EPROTO; + + return 0; +} + +static int oa_tc6_perform_ctrl(struct oa_tc6 *tc6, u32 address, u32 value[], + u8 length, enum oa_tc6_register_op reg_op) +{ + u16 size; + int ret; + + /* Prepare control command and copy to SPI control buffer */ + oa_tc6_prepare_ctrl_spi_buf(tc6, address, value, length, reg_op); + + size = oa_tc6_calculate_ctrl_buf_size(length); + + /* Perform SPI transfer */ + ret = oa_tc6_spi_transfer(tc6, OA_TC6_CTRL_HEADER, size); + if (ret) { + dev_err(&tc6->spi->dev, "SPI transfer failed for control: %d\n", + ret); + return ret; + } + + /* Check echoed/received control write command reply for errors */ + return oa_tc6_check_ctrl_write_reply(tc6, size); +} + +/** + * oa_tc6_write_registers - function for writing multiple consecutive registers. + * @tc6: oa_tc6 struct. + * @address: address of the first register to be written in the MAC-PHY. + * @value: values to be written from the starting register address @address. + * @length: number of consecutive registers to be written from @address. + * + * Maximum of 128 consecutive registers can be written starting at @address. + * + * Return: 0 on success otherwise failed. + */ +int oa_tc6_write_registers(struct oa_tc6 *tc6, u32 address, u32 value[], + u8 length) +{ + int ret; + + if (!length || length > OA_TC6_CTRL_MAX_REGISTERS) { + dev_err(&tc6->spi->dev, "Invalid register length parameter\n"); + return -EINVAL; + } + + mutex_lock(&tc6->spi_ctrl_lock); + ret = oa_tc6_perform_ctrl(tc6, address, value, length, + OA_TC6_CTRL_REG_WRITE); + mutex_unlock(&tc6->spi_ctrl_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(oa_tc6_write_registers); + +/** + * oa_tc6_write_register - function for writing a MAC-PHY register. + * @tc6: oa_tc6 struct. + * @address: register address of the MAC-PHY to be written. + * @value: value to be written in the @address register address of the MAC-PHY. + * + * Return: 0 on success otherwise failed. + */ +int oa_tc6_write_register(struct oa_tc6 *tc6, u32 address, u32 value) +{ + return oa_tc6_write_registers(tc6, address, &value, 1); +} +EXPORT_SYMBOL_GPL(oa_tc6_write_register); + +/** + * oa_tc6_init - allocates and initializes oa_tc6 structure. + * @spi: device with which data will be exchanged. + * + * Return: pointer reference to the oa_tc6 structure if the MAC-PHY + * initialization is successful otherwise NULL. + */ +struct oa_tc6 *oa_tc6_init(struct spi_device *spi) +{ + struct oa_tc6 *tc6; + + tc6 = devm_kzalloc(&spi->dev, sizeof(*tc6), GFP_KERNEL); + if (!tc6) + return NULL; + + tc6->spi = spi; + mutex_init(&tc6->spi_ctrl_lock); + + /* Set the SPI controller to pump at realtime priority */ + tc6->spi->rt = true; + spi_setup(tc6->spi); + + tc6->spi_ctrl_tx_buf = devm_kzalloc(&tc6->spi->dev, + OA_TC6_CTRL_SPI_BUF_SIZE, + GFP_KERNEL); + if (!tc6->spi_ctrl_tx_buf) + return NULL; + + tc6->spi_ctrl_rx_buf = devm_kzalloc(&tc6->spi->dev, + OA_TC6_CTRL_SPI_BUF_SIZE, + GFP_KERNEL); + if (!tc6->spi_ctrl_rx_buf) + return NULL; + + return tc6; +} +EXPORT_SYMBOL_GPL(oa_tc6_init); + +MODULE_DESCRIPTION("OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface Lib"); +MODULE_AUTHOR("Parthiban Veerasooran "); +MODULE_LICENSE("GPL"); diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h new file mode 100644 index 000000000000..99c490f1c8a8 --- /dev/null +++ b/include/linux/oa_tc6.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface framework + * + * Link: https://opensig.org/download/document/OPEN_Alliance_10BASET1x_MAC-PHY_Serial_Interface_V1.1.pdf + * + * Author: Parthiban Veerasooran + */ + +#include + +struct oa_tc6; + +struct oa_tc6 *oa_tc6_init(struct spi_device *spi); +int oa_tc6_write_register(struct oa_tc6 *tc6, u32 address, u32 value); +int oa_tc6_write_registers(struct oa_tc6 *tc6, u32 address, u32 value[], + u8 length);