diff options
author | Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com> | 2023-02-07 19:48:12 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-08 15:10:15 +0300 |
commit | 32bb477fa7bf386ce87837691c4672854a5231e4 (patch) | |
tree | a77be659a6596525f18c1080fa25a6cf264898e1 /drivers/tty | |
parent | 0348386dab3711b8caa0422c2a4852913b8bf4d7 (diff) | |
download | linux-32bb477fa7bf386ce87837691c4672854a5231e4.tar.xz |
serial: 8250_pci1xxxx: Add driver for quad-uart support
pci1xxxx is a PCIe switch with a multi-function endpoint on one of
its downstream ports. Quad-uart is one of the functions in the
multi-function endpoint. This driver loads for the quad-uart and
enumerates single or multiple instances of uart based on the PCIe
subsystem device ID.
Co-developed-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Signed-off-by: Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230207164814.3104605-3-kumaravel.thiagarajan@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r-- | drivers/tty/serial/8250/8250_pci1xxxx.c | 329 | ||||
-rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 8 | ||||
-rw-r--r-- | drivers/tty/serial/8250/Kconfig | 11 | ||||
-rw-r--r-- | drivers/tty/serial/8250/Makefile | 1 |
4 files changed, 349 insertions, 0 deletions
diff --git a/drivers/tty/serial/8250/8250_pci1xxxx.c b/drivers/tty/serial/8250/8250_pci1xxxx.c new file mode 100644 index 000000000000..ea04c014edb9 --- /dev/null +++ b/drivers/tty/serial/8250/8250_pci1xxxx.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Probe module for 8250/16550-type MCHP PCI serial ports. + * + * Based on drivers/tty/serial/8250/8250_pci.c, + * + * Copyright (C) 2022 Microchip Technology Inc., All Rights Reserved. + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/serial_core.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/units.h> +#include <linux/tty.h> + +#include <asm/byteorder.h> + +#include "8250.h" +#include "8250_pcilib.h" + +#define PCI_DEVICE_ID_EFAR_PCI12000 0xa002 +#define PCI_DEVICE_ID_EFAR_PCI11010 0xa012 +#define PCI_DEVICE_ID_EFAR_PCI11101 0xa022 +#define PCI_DEVICE_ID_EFAR_PCI11400 0xa032 +#define PCI_DEVICE_ID_EFAR_PCI11414 0xa042 + +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_4p 0x0001 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p012 0x0002 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p013 0x0003 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p023 0x0004 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p123 0x0005 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p01 0x0006 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p02 0x0007 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p03 0x0008 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p12 0x0009 +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p13 0x000a +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p23 0x000b +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p0 0x000c +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p1 0x000d +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p2 0x000e +#define PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p3 0x000f + +#define PCI_SUBDEVICE_ID_EFAR_PCI12000 PCI_DEVICE_ID_EFAR_PCI12000 +#define PCI_SUBDEVICE_ID_EFAR_PCI11010 PCI_DEVICE_ID_EFAR_PCI11010 +#define PCI_SUBDEVICE_ID_EFAR_PCI11101 PCI_DEVICE_ID_EFAR_PCI11101 +#define PCI_SUBDEVICE_ID_EFAR_PCI11400 PCI_DEVICE_ID_EFAR_PCI11400 +#define PCI_SUBDEVICE_ID_EFAR_PCI11414 PCI_DEVICE_ID_EFAR_PCI11414 + +#define UART_ACTV_REG 0x11 +#define UART_BLOCK_SET_ACTIVE BIT(0) + +#define UART_PCI_CTRL_REG 0x80 +#define UART_PCI_CTRL_SET_MULTIPLE_MSI BIT(4) +#define UART_PCI_CTRL_D3_CLK_ENABLE BIT(0) + +#define ADCL_CFG_REG 0x40 +#define ADCL_CFG_POL_SEL BIT(2) +#define ADCL_CFG_PIN_SEL BIT(1) +#define ADCL_CFG_EN BIT(0) + +#define UART_BIT_SAMPLE_CNT 16 +#define BAUD_CLOCK_DIV_INT_MSK GENMASK(31, 8) +#define ADCL_CFG_RTS_DELAY_MASK GENMASK(11, 8) +#define UART_CLOCK_DEFAULT (62500 * HZ_PER_KHZ) + +#define UART_WAKE_REG 0x8C +#define UART_WAKE_MASK_REG 0x90 +#define UART_WAKE_N_PIN BIT(2) +#define UART_WAKE_NCTS BIT(1) +#define UART_WAKE_INT BIT(0) +#define UART_WAKE_SRCS \ + (UART_WAKE_N_PIN | UART_WAKE_NCTS | UART_WAKE_INT) + +#define UART_BAUD_CLK_DIVISOR_REG 0x54 + +#define UART_RESET_REG 0x94 +#define UART_RESET_D3_RESET_DISABLE BIT(16) + +#define MAX_PORTS 4 +#define PORT_OFFSET 0x100 + +static const int logical_to_physical_port_idx[][MAX_PORTS] = { + {0, 1, 2, 3}, /* PCI12000, PCI11010, PCI11101, PCI11400, PCI11414 */ + {0, 1, 2, 3}, /* PCI4p */ + {0, 1, 2, -1}, /* PCI3p012 */ + {0, 1, 3, -1}, /* PCI3p013 */ + {0, 2, 3, -1}, /* PCI3p023 */ + {1, 2, 3, -1}, /* PCI3p123 */ + {0, 1, -1, -1}, /* PCI2p01 */ + {0, 2, -1, -1}, /* PCI2p02 */ + {0, 3, -1, -1}, /* PCI2p03 */ + {1, 2, -1, -1}, /* PCI2p12 */ + {1, 3, -1, -1}, /* PCI2p13 */ + {2, 3, -1, -1}, /* PCI2p23 */ + {0, -1, -1, -1}, /* PCI1p0 */ + {1, -1, -1, -1}, /* PCI1p1 */ + {2, -1, -1, -1}, /* PCI1p2 */ + {3, -1, -1, -1}, /* PCI1p3 */ +}; + +struct pci1xxxx_8250 { + unsigned int nr; + void __iomem *membase; + int line[]; +}; + +static int pci1xxxx_get_num_ports(struct pci_dev *dev) +{ + switch (dev->subsystem_device) { + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p0: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p1: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p2: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p3: + case PCI_SUBDEVICE_ID_EFAR_PCI12000: + case PCI_SUBDEVICE_ID_EFAR_PCI11010: + case PCI_SUBDEVICE_ID_EFAR_PCI11101: + case PCI_SUBDEVICE_ID_EFAR_PCI11400: + default: + return 1; + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p01: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p02: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p03: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p12: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p13: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_2p23: + return 2; + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p012: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p123: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p013: + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_3p023: + return 3; + case PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_4p: + case PCI_SUBDEVICE_ID_EFAR_PCI11414: + return 4; + } +} + +static unsigned int pci1xxxx_get_divisor(struct uart_port *port, + unsigned int baud, unsigned int *frac) +{ + unsigned int quot; + + /* + * Calculate baud rate sampling period in nanoseconds. + * Fractional part x denotes x/255 parts of a nanosecond. + */ + quot = NSEC_PER_SEC / (baud * UART_BIT_SAMPLE_CNT); + *frac = (NSEC_PER_SEC - quot * baud * UART_BIT_SAMPLE_CNT) * + 255 / UART_BIT_SAMPLE_CNT / baud; + + return quot; +} + +static void pci1xxxx_set_divisor(struct uart_port *port, unsigned int baud, + unsigned int quot, unsigned int frac) +{ + writel(FIELD_PREP(BAUD_CLOCK_DIV_INT_MSK, quot) | frac, + port->membase + UART_BAUD_CLK_DIVISOR_REG); +} + +static int pci1xxxx_setup(struct pci_dev *pdev, + struct uart_8250_port *port, int port_idx) +{ + int ret; + + port->port.flags |= UPF_FIXED_TYPE | UPF_SKIP_TEST; + port->port.type = PORT_MCHP16550A; + port->port.set_termios = serial8250_do_set_termios; + port->port.get_divisor = pci1xxxx_get_divisor; + port->port.set_divisor = pci1xxxx_set_divisor; + + ret = serial8250_pci_setup_port(pdev, port, 0, PORT_OFFSET * port_idx, 0); + if (ret < 0) + return ret; + + writeb(UART_BLOCK_SET_ACTIVE, port->port.membase + UART_ACTV_REG); + writeb(UART_WAKE_SRCS, port->port.membase + UART_WAKE_REG); + writeb(UART_WAKE_N_PIN, port->port.membase + UART_WAKE_MASK_REG); + + return 0; +} + +static unsigned int pci1xxxx_get_max_port(int subsys_dev) +{ + unsigned int i = MAX_PORTS; + + if (subsys_dev < ARRAY_SIZE(logical_to_physical_port_idx)) + while (i--) { + if (logical_to_physical_port_idx[subsys_dev][i] != -1) + return logical_to_physical_port_idx[subsys_dev][i] + 1; + } + + if (subsys_dev == PCI_SUBDEVICE_ID_EFAR_PCI11414) + return 4; + + return 1; +} + +static int pci1xxxx_logical_to_physical_port_translate(int subsys_dev, int port) +{ + if (subsys_dev < ARRAY_SIZE(logical_to_physical_port_idx)) + return logical_to_physical_port_idx[subsys_dev][port]; + + return logical_to_physical_port_idx[0][port]; +} + +static int pci1xxxx_serial_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + struct device *dev = &pdev->dev; + struct pci1xxxx_8250 *priv; + struct uart_8250_port uart; + unsigned int max_vec_reqd; + unsigned int nr_ports, i; + int num_vectors; + int subsys_dev; + int port_idx; + int rc; + + rc = pcim_enable_device(pdev); + if (rc) + return rc; + + nr_ports = pci1xxxx_get_num_ports(pdev); + + priv = devm_kzalloc(dev, struct_size(priv, line, nr_ports), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->membase = pci_ioremap_bar(pdev, 0); + if (!priv->membase) + return -ENOMEM; + + pci_set_master(pdev); + + priv->nr = nr_ports; + + subsys_dev = pdev->subsystem_device; + max_vec_reqd = pci1xxxx_get_max_port(subsys_dev); + + num_vectors = pci_alloc_irq_vectors(pdev, 1, max_vec_reqd, PCI_IRQ_ALL_TYPES); + if (num_vectors < 0) { + pci_iounmap(pdev, priv->membase); + return num_vectors; + } + + memset(&uart, 0, sizeof(uart)); + uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT; + uart.port.uartclk = UART_CLOCK_DEFAULT; + uart.port.dev = dev; + + if (num_vectors == max_vec_reqd) + writeb(UART_PCI_CTRL_SET_MULTIPLE_MSI, priv->membase + UART_PCI_CTRL_REG); + + for (i = 0; i < nr_ports; i++) { + priv->line[i] = -ENODEV; + + port_idx = pci1xxxx_logical_to_physical_port_translate(subsys_dev, i); + + if (num_vectors == max_vec_reqd) + uart.port.irq = pci_irq_vector(pdev, port_idx); + else + uart.port.irq = pci_irq_vector(pdev, 0); + + rc = pci1xxxx_setup(pdev, &uart, port_idx); + if (rc) { + dev_warn(dev, "Failed to setup port %u\n", i); + continue; + } + + priv->line[i] = serial8250_register_8250_port(&uart); + if (priv->line[i] < 0) { + dev_warn(dev, + "Couldn't register serial port %lx, irq %d, type %d, error %d\n", + uart.port.iobase, uart.port.irq, uart.port.iotype, + priv->line[i]); + } + } + + pci_set_drvdata(pdev, priv); + + return 0; +} + +static void pci1xxxx_serial_remove(struct pci_dev *dev) +{ + struct pci1xxxx_8250 *priv = pci_get_drvdata(dev); + unsigned int i; + + for (i = 0; i < priv->nr; i++) { + if (priv->line[i] >= 0) + serial8250_unregister_port(priv->line[i]); + } + + pci_free_irq_vectors(dev); + pci_iounmap(dev, priv->membase); +} + +static const struct pci_device_id pci1xxxx_pci_tbl[] = { + { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11010) }, + { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11101) }, + { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11400) }, + { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI11414) }, + { PCI_VDEVICE(EFAR, PCI_DEVICE_ID_EFAR_PCI12000) }, + {} +}; +MODULE_DEVICE_TABLE(pci, pci1xxxx_pci_tbl); + +static struct pci_driver pci1xxxx_pci_driver = { + .name = "pci1xxxx serial", + .probe = pci1xxxx_serial_probe, + .remove = pci1xxxx_serial_remove, + .id_table = pci1xxxx_pci_tbl, +}; +module_pci_driver(pci1xxxx_pci_driver); + +static_assert((ARRAY_SIZE(logical_to_physical_port_idx) == PCI_SUBDEVICE_ID_EFAR_PCI1XXXX_1p3 + 1)); + +MODULE_IMPORT_NS(SERIAL_8250_PCI); +MODULE_DESCRIPTION("Microchip Technology Inc. PCIe to UART module"); +MODULE_AUTHOR("Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>"); +MODULE_AUTHOR("Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index e61753c295d5..fa43df05342b 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -313,6 +313,14 @@ static const struct serial8250_config uart_config[] = { .rxtrig_bytes = {1, 4, 8, 14}, .flags = UART_CAP_FIFO, }, + [PORT_MCHP16550A] = { + .name = "MCHP16550A", + .fifo_size = 256, + .tx_loadsz = 256, + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01, + .rxtrig_bytes = {2, 66, 130, 194}, + .flags = UART_CAP_FIFO, + }, }; /* Uart divisor latch read */ diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig index 9b3ba28cc562..978dc196c29b 100644 --- a/drivers/tty/serial/8250/Kconfig +++ b/drivers/tty/serial/8250/Kconfig @@ -295,6 +295,17 @@ config SERIAL_8250_HUB6 To compile this driver as a module, choose M here: the module will be called 8250_hub6. +config SERIAL_8250_PCI1XXXX + tristate "Microchip 8250 based serial port" + depends on SERIAL_8250 && PCI + select SERIAL_8250_PCILIB + default SERIAL_8250 + help + Select this option if you have a setup with Microchip PCIe + Switch with serial port enabled and wish to enable 8250 + serial driver for the serial interface. This driver support + will ensure to support baud rates upto 1.5Mpbs. + # # Misc. options/drivers. # diff --git a/drivers/tty/serial/8250/Makefile b/drivers/tty/serial/8250/Makefile index ce63a250da3b..4fc2fc1f41b6 100644 --- a/drivers/tty/serial/8250/Makefile +++ b/drivers/tty/serial/8250/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_SERIAL_8250_ACCENT) += 8250_accent.o obj-$(CONFIG_SERIAL_8250_BOCA) += 8250_boca.o obj-$(CONFIG_SERIAL_8250_EXAR_ST16C554) += 8250_exar_st16c554.o obj-$(CONFIG_SERIAL_8250_HUB6) += 8250_hub6.o +obj-$(CONFIG_SERIAL_8250_PCI1XXXX) += 8250_pci1xxxx.o obj-$(CONFIG_SERIAL_8250_FSL) += 8250_fsl.o obj-$(CONFIG_SERIAL_8250_MEN_MCB) += 8250_men_mcb.o obj-$(CONFIG_SERIAL_8250_DFL) += 8250_dfl.o |