// 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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_SYSTEM_ADDR_BASE 0x1000 #define UART_DEV_REV_REG (UART_SYSTEM_ADDR_BASE + 0x00) #define UART_DEV_REV_MASK GENMASK(7, 0) #define UART_SYSLOCK_REG (UART_SYSTEM_ADDR_BASE + 0xA0) #define UART_SYSLOCK BIT(2) #define SYSLOCK_SLEEP_TIMEOUT 100 #define SYSLOCK_RETRY_CNT 1000 #define UART_RX_BYTE_FIFO 0x00 #define UART_FIFO_CTL 0x02 #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 UART_BURST_STATUS_REG 0x9C #define UART_RX_BURST_FIFO 0xA4 #define MAX_PORTS 4 #define PORT_OFFSET 0x100 #define RX_BUF_SIZE 512 #define UART_BYTE_SIZE 1 #define UART_BURST_SIZE 4 #define UART_BST_STAT_RX_COUNT_MASK 0x00FF #define UART_BST_STAT_IIR_INT_PEND 0x100000 #define UART_LSR_OVERRUN_ERR_CLR 0x43 #define UART_BST_STAT_LSR_RX_MASK 0x9F000000 #define UART_BST_STAT_LSR_RX_ERR_MASK 0x9E000000 #define UART_BST_STAT_LSR_OVERRUN_ERR 0x2000000 #define UART_BST_STAT_LSR_PARITY_ERR 0x4000000 #define UART_BST_STAT_LSR_FRAME_ERR 0x8000000 struct pci1xxxx_8250 { unsigned int nr; u8 dev_rev; u8 pad[3]; void __iomem *membase; int line[] __counted_by(nr); }; static const struct serial_rs485 pci1xxxx_rs485_supported = { .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND, .delay_rts_after_send = 1, /* Delay RTS before send is not supported */ }; static int pci1xxxx_set_sys_lock(struct pci1xxxx_8250 *port) { writel(UART_SYSLOCK, port->membase + UART_SYSLOCK_REG); return readl(port->membase + UART_SYSLOCK_REG); } static int pci1xxxx_acquire_sys_lock(struct pci1xxxx_8250 *port) { u32 regval; return readx_poll_timeout(pci1xxxx_set_sys_lock, port, regval, (regval & UART_SYSLOCK), SYSLOCK_SLEEP_TIMEOUT, SYSLOCK_RETRY_CNT * SYSLOCK_SLEEP_TIMEOUT); } static void pci1xxxx_release_sys_lock(struct pci1xxxx_8250 *port) { writel(0x0, port->membase + UART_SYSLOCK_REG); } 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 */ }; 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_rs485_config(struct uart_port *port, struct ktermios *termios, struct serial_rs485 *rs485) { u32 delay_in_baud_periods; u32 baud_period_in_ns; u32 mode_cfg = 0; u32 clock_div; /* * pci1xxxx's uart hardware supports only RTS delay after * Tx and in units of bit times to a maximum of 15 */ if (rs485->flags & SER_RS485_ENABLED) { mode_cfg = ADCL_CFG_EN | ADCL_CFG_PIN_SEL; if (!(rs485->flags & SER_RS485_RTS_ON_SEND)) mode_cfg |= ADCL_CFG_POL_SEL; if (rs485->delay_rts_after_send) { clock_div = readl(port->membase + UART_BAUD_CLK_DIVISOR_REG); baud_period_in_ns = FIELD_GET(BAUD_CLOCK_DIV_INT_MSK, clock_div) * UART_BIT_SAMPLE_CNT; delay_in_baud_periods = rs485->delay_rts_after_send * NSEC_PER_MSEC / baud_period_in_ns; delay_in_baud_periods = min_t(u32, delay_in_baud_periods, FIELD_MAX(ADCL_CFG_RTS_DELAY_MASK)); mode_cfg |= FIELD_PREP(ADCL_CFG_RTS_DELAY_MASK, delay_in_baud_periods); rs485->delay_rts_after_send = baud_period_in_ns * delay_in_baud_periods / NSEC_PER_MSEC; } } writel(mode_cfg, port->membase + ADCL_CFG_REG); return 0; } static u32 pci1xxxx_read_burst_status(struct uart_port *port) { u32 status; status = readl(port->membase + UART_BURST_STATUS_REG); if (status & UART_BST_STAT_LSR_RX_ERR_MASK) { if (status & UART_BST_STAT_LSR_OVERRUN_ERR) { writeb(UART_LSR_OVERRUN_ERR_CLR, port->membase + UART_FIFO_CTL); port->icount.overrun++; } if (status & UART_BST_STAT_LSR_FRAME_ERR) port->icount.frame++; if (status & UART_BST_STAT_LSR_PARITY_ERR) port->icount.parity++; } return status; } static void pci1xxxx_process_read_data(struct uart_port *port, unsigned char *rx_buff, u32 *buff_index, u32 *valid_byte_count) { u32 valid_burst_count = *valid_byte_count / UART_BURST_SIZE; u32 *burst_buf; /* * Depending on the RX Trigger Level the number of bytes that can be * stored in RX FIFO at a time varies. Each transaction reads data * in DWORDs. If there are less than four remaining valid_byte_count * to read, the data is received one byte at a time. */ while (valid_burst_count--) { if (*buff_index > (RX_BUF_SIZE - UART_BURST_SIZE)) break; burst_buf = (u32 *)&rx_buff[*buff_index]; *burst_buf = readl(port->membase + UART_RX_BURST_FIFO); *buff_index += UART_BURST_SIZE; *valid_byte_count -= UART_BURST_SIZE; } while (*valid_byte_count) { if (*buff_index >= RX_BUF_SIZE) break; rx_buff[*buff_index] = readb(port->membase + UART_RX_BYTE_FIFO); *buff_index += UART_BYTE_SIZE; *valid_byte_count -= UART_BYTE_SIZE; } } static void pci1xxxx_rx_burst(struct uart_port *port, u32 uart_status) { u32 valid_byte_count = uart_status & UART_BST_STAT_RX_COUNT_MASK; struct tty_port *tty_port = &port->state->port; unsigned char rx_buff[RX_BUF_SIZE]; u32 buff_index = 0; u32 copied_len; if (valid_byte_count != 0 && valid_byte_count < RX_BUF_SIZE) { pci1xxxx_process_read_data(port, rx_buff, &buff_index, &valid_byte_count); copied_len = (u32)tty_insert_flip_string(tty_port, rx_buff, buff_index); if (copied_len != buff_index) port->icount.overrun += buff_index - copied_len; port->icount.rx += buff_index; tty_flip_buffer_push(tty_port); } } static int pci1xxxx_handle_irq(struct uart_port *port) { unsigned long flags; u32 status; status = pci1xxxx_read_burst_status(port); if (status & UART_BST_STAT_IIR_INT_PEND) return 0; spin_lock_irqsave(&port->lock, flags); if (status & UART_BST_STAT_LSR_RX_MASK) pci1xxxx_rx_burst(port, status); spin_unlock_irqrestore(&port->lock, flags); return 1; } static bool pci1xxxx_port_suspend(int line) { struct uart_8250_port *up = serial8250_get_port(line); struct uart_port *port = &up->port; struct tty_port *tport = &port->state->port; unsigned long flags; bool ret = false; u8 wakeup_mask; mutex_lock(&tport->mutex); if (port->suspended == 0 && port->dev) { wakeup_mask = readb(up->port.membase + UART_WAKE_MASK_REG); uart_port_lock_irqsave(port, &flags); port->mctrl &= ~TIOCM_OUT2; port->ops->set_mctrl(port, port->mctrl); uart_port_unlock_irqrestore(port, flags); ret = (wakeup_mask & UART_WAKE_SRCS) != UART_WAKE_SRCS; } writeb(UART_WAKE_SRCS, port->membase + UART_WAKE_REG); mutex_unlock(&tport->mutex); return ret; } static void pci1xxxx_port_resume(int line) { struct uart_8250_port *up = serial8250_get_port(line); struct uart_port *port = &up->port; struct tty_port *tport = &port->state->port; unsigned long flags; mutex_lock(&tport->mutex); writeb(UART_BLOCK_SET_ACTIVE, port->membase + UART_ACTV_REG); writeb(UART_WAKE_SRCS, port->membase + UART_WAKE_REG); if (port->suspended == 0) { uart_port_lock_irqsave(port, &flags); port->mctrl |= TIOCM_OUT2; port->ops->set_mctrl(port, port->mctrl); uart_port_unlock_irqrestore(port, flags); } mutex_unlock(&tport->mutex); } static int pci1xxxx_suspend(struct device *dev) { struct pci1xxxx_8250 *priv = dev_get_drvdata(dev); struct pci_dev *pcidev = to_pci_dev(dev); bool wakeup = false; unsigned int data; void __iomem *p; int i; for (i = 0; i < priv->nr; i++) { if (priv->line[i] >= 0) { serial8250_suspend_port(priv->line[i]); wakeup |= pci1xxxx_port_suspend(priv->line[i]); } } p = pci_ioremap_bar(pcidev, 0); if (!p) { dev_err(dev, "remapping of bar 0 memory failed"); return -ENOMEM; } data = readl(p + UART_RESET_REG); writel(data | UART_RESET_D3_RESET_DISABLE, p + UART_RESET_REG); if (wakeup) writeb(UART_PCI_CTRL_D3_CLK_ENABLE, p + UART_PCI_CTRL_REG); iounmap(p); device_set_wakeup_enable(dev, true); pci_wake_from_d3(pcidev, true); return 0; } static int pci1xxxx_resume(struct device *dev) { struct pci1xxxx_8250 *priv = dev_get_drvdata(dev); struct pci_dev *pcidev = to_pci_dev(dev); unsigned int data; void __iomem *p; int i; p = pci_ioremap_bar(pcidev, 0); if (!p) { dev_err(dev, "remapping of bar 0 memory failed"); return -ENOMEM; } data = readl(p + UART_RESET_REG); writel(data & ~UART_RESET_D3_RESET_DISABLE, p + UART_RESET_REG); iounmap(p); for (i = 0; i < priv->nr; i++) { if (priv->line[i] >= 0) { pci1xxxx_port_resume(priv->line[i]); serial8250_resume_port(priv->line[i]); } } return 0; } static int pci1xxxx_setup(struct pci_dev *pdev, struct uart_8250_port *port, int port_idx, int rev) { 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; port->port.rs485_config = pci1xxxx_rs485_config; port->port.rs485_supported = pci1xxxx_rs485_supported; /* From C0 rev Burst operation is supported */ if (rev >= 0xC0) port->port.handle_irq = pci1xxxx_handle_irq; 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_get_device_revision(struct pci1xxxx_8250 *priv) { u32 regval; int ret; /* * DEV REV is a system register, HW Syslock bit * should be acquired before accessing the register */ ret = pci1xxxx_acquire_sys_lock(priv); if (ret) return ret; regval = readl(priv->membase + UART_DEV_REV_REG); priv->dev_rev = regval & UART_DEV_REV_MASK; pci1xxxx_release_sys_lock(priv); return 0; } 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 ret; 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; ret = pci1xxxx_get_device_revision(priv); if (ret) return ret; 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, priv->dev_rev); 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 DEFINE_SIMPLE_DEV_PM_OPS(pci1xxxx_pm_ops, pci1xxxx_suspend, pci1xxxx_resume); 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, .driver = { .pm = pm_sleep_ptr(&pci1xxxx_pm_ops), }, .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 "); MODULE_AUTHOR("Tharun Kumar P "); MODULE_LICENSE("GPL");