Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Andy Shevchenko | 1691 | 99.18% | 8 | 66.67% |
Eugeniy Paltsev | 7 | 0.41% | 1 | 8.33% |
Jan Kiszka | 5 | 0.29% | 1 | 8.33% |
Greg Kroah-Hartman | 2 | 0.12% | 2 | 16.67% |
Total | 1705 | 12 |
// SPDX-License-Identifier: GPL-2.0 /* * 8250_lpss.c - Driver for UART on Intel Braswell and various other Intel SoCs * * Copyright (C) 2016 Intel Corporation * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com> */ #include <linux/bitops.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/rational.h> #include <linux/dmaengine.h> #include <linux/dma/dw.h> #include "8250.h" #define PCI_DEVICE_ID_INTEL_QRK_UARTx 0x0936 #define PCI_DEVICE_ID_INTEL_BYT_UART1 0x0f0a #define PCI_DEVICE_ID_INTEL_BYT_UART2 0x0f0c #define PCI_DEVICE_ID_INTEL_BSW_UART1 0x228a #define PCI_DEVICE_ID_INTEL_BSW_UART2 0x228c #define PCI_DEVICE_ID_INTEL_BDW_UART1 0x9ce3 #define PCI_DEVICE_ID_INTEL_BDW_UART2 0x9ce4 /* Intel LPSS specific registers */ #define BYT_PRV_CLK 0x800 #define BYT_PRV_CLK_EN BIT(0) #define BYT_PRV_CLK_M_VAL_SHIFT 1 #define BYT_PRV_CLK_N_VAL_SHIFT 16 #define BYT_PRV_CLK_UPDATE BIT(31) #define BYT_TX_OVF_INT 0x820 #define BYT_TX_OVF_INT_MASK BIT(1) struct lpss8250; struct lpss8250_board { unsigned long freq; unsigned int base_baud; int (*setup)(struct lpss8250 *, struct uart_port *p); void (*exit)(struct lpss8250 *); }; struct lpss8250 { int line; struct lpss8250_board *board; /* DMA parameters */ struct uart_8250_dma dma; struct dw_dma_chip dma_chip; struct dw_dma_slave dma_param; u8 dma_maxburst; }; static void byt_set_termios(struct uart_port *p, struct ktermios *termios, struct ktermios *old) { unsigned int baud = tty_termios_baud_rate(termios); struct lpss8250 *lpss = p->private_data; unsigned long fref = lpss->board->freq, fuart = baud * 16; unsigned long w = BIT(15) - 1; unsigned long m, n; u32 reg; /* Gracefully handle the B0 case: fall back to B9600 */ fuart = fuart ? fuart : 9600 * 16; /* Get Fuart closer to Fref */ fuart *= rounddown_pow_of_two(fref / fuart); /* * For baud rates 0.5M, 1M, 1.5M, 2M, 2.5M, 3M, 3.5M and 4M the * dividers must be adjusted. * * uartclk = (m / n) * 100 MHz, where m <= n */ rational_best_approximation(fuart, fref, w, w, &m, &n); p->uartclk = fuart; /* Reset the clock */ reg = (m << BYT_PRV_CLK_M_VAL_SHIFT) | (n << BYT_PRV_CLK_N_VAL_SHIFT); writel(reg, p->membase + BYT_PRV_CLK); reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE; writel(reg, p->membase + BYT_PRV_CLK); p->status &= ~UPSTAT_AUTOCTS; if (termios->c_cflag & CRTSCTS) p->status |= UPSTAT_AUTOCTS; serial8250_do_set_termios(p, termios, old); } static unsigned int byt_get_mctrl(struct uart_port *port) { unsigned int ret = serial8250_do_get_mctrl(port); /* Force DCD and DSR signals to permanently be reported as active */ ret |= TIOCM_CAR | TIOCM_DSR; return ret; } static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { struct dw_dma_slave *param = &lpss->dma_param; struct uart_8250_port *up = up_to_u8250p(port); struct pci_dev *pdev = to_pci_dev(port->dev); unsigned int dma_devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0); struct pci_dev *dma_dev = pci_get_slot(pdev->bus, dma_devfn); switch (pdev->device) { case PCI_DEVICE_ID_INTEL_BYT_UART1: case PCI_DEVICE_ID_INTEL_BSW_UART1: case PCI_DEVICE_ID_INTEL_BDW_UART1: param->src_id = 3; param->dst_id = 2; break; case PCI_DEVICE_ID_INTEL_BYT_UART2: case PCI_DEVICE_ID_INTEL_BSW_UART2: case PCI_DEVICE_ID_INTEL_BDW_UART2: param->src_id = 5; param->dst_id = 4; break; default: return -EINVAL; } param->dma_dev = &dma_dev->dev; param->m_master = 0; param->p_master = 1; /* TODO: Detect FIFO size automaticaly for DesignWare 8250 */ port->fifosize = 64; up->tx_loadsz = 64; lpss->dma_maxburst = 16; port->set_termios = byt_set_termios; port->get_mctrl = byt_get_mctrl; /* Disable TX counter interrupts */ writel(BYT_TX_OVF_INT_MASK, port->membase + BYT_TX_OVF_INT); return 0; } #ifdef CONFIG_SERIAL_8250_DMA static const struct dw_dma_platform_data qrk_serial_dma_pdata = { .nr_channels = 2, .chan_allocation_order = CHAN_ALLOCATION_ASCENDING, .chan_priority = CHAN_PRIORITY_ASCENDING, .block_size = 4095, .nr_masters = 1, .data_width = {4}, .multi_block = {0}, }; static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port) { struct uart_8250_dma *dma = &lpss->dma; struct dw_dma_chip *chip = &lpss->dma_chip; struct dw_dma_slave *param = &lpss->dma_param; struct pci_dev *pdev = to_pci_dev(port->dev); int ret; chip->dev = &pdev->dev; chip->irq = pci_irq_vector(pdev, 0); chip->regs = pci_ioremap_bar(pdev, 1); chip->pdata = &qrk_serial_dma_pdata; /* Falling back to PIO mode if DMA probing fails */ ret = dw_dma_probe(chip); if (ret) return; pci_try_set_mwi(pdev); /* Special DMA address for UART */ dma->rx_dma_addr = 0xfffff000; dma->tx_dma_addr = 0xfffff000; param->dma_dev = &pdev->dev; param->src_id = 0; param->dst_id = 1; param->hs_polarity = true; lpss->dma_maxburst = 8; } static void qrk_serial_exit_dma(struct lpss8250 *lpss) { struct dw_dma_slave *param = &lpss->dma_param; if (!param->dma_dev) return; dw_dma_remove(&lpss->dma_chip); } #else /* CONFIG_SERIAL_8250_DMA */ static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port) {} static void qrk_serial_exit_dma(struct lpss8250 *lpss) {} #endif /* !CONFIG_SERIAL_8250_DMA */ static int qrk_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { struct pci_dev *pdev = to_pci_dev(port->dev); int ret; pci_set_master(pdev); ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES); if (ret < 0) return ret; port->irq = pci_irq_vector(pdev, 0); qrk_serial_setup_dma(lpss, port); return 0; } static void qrk_serial_exit(struct lpss8250 *lpss) { qrk_serial_exit_dma(lpss); } static bool lpss8250_dma_filter(struct dma_chan *chan, void *param) { struct dw_dma_slave *dws = param; if (dws->dma_dev != chan->device->dev) return false; chan->private = dws; return true; } static int lpss8250_dma_setup(struct lpss8250 *lpss, struct uart_8250_port *port) { struct uart_8250_dma *dma = &lpss->dma; struct dw_dma_slave *rx_param, *tx_param; struct device *dev = port->port.dev; if (!lpss->dma_param.dma_dev) return 0; rx_param = devm_kzalloc(dev, sizeof(*rx_param), GFP_KERNEL); if (!rx_param) return -ENOMEM; tx_param = devm_kzalloc(dev, sizeof(*tx_param), GFP_KERNEL); if (!tx_param) return -ENOMEM; *rx_param = lpss->dma_param; dma->rxconf.src_maxburst = lpss->dma_maxburst; *tx_param = lpss->dma_param; dma->txconf.dst_maxburst = lpss->dma_maxburst; dma->fn = lpss8250_dma_filter; dma->rx_param = rx_param; dma->tx_param = tx_param; port->dma = dma; return 0; } static int lpss8250_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct uart_8250_port uart; struct lpss8250 *lpss; int ret; ret = pcim_enable_device(pdev); if (ret) return ret; lpss = devm_kzalloc(&pdev->dev, sizeof(*lpss), GFP_KERNEL); if (!lpss) return -ENOMEM; lpss->board = (struct lpss8250_board *)id->driver_data; memset(&uart, 0, sizeof(struct uart_8250_port)); uart.port.dev = &pdev->dev; uart.port.irq = pdev->irq; uart.port.private_data = lpss; uart.port.type = PORT_16550A; uart.port.iotype = UPIO_MEM; uart.port.regshift = 2; uart.port.uartclk = lpss->board->base_baud * 16; uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE; uart.capabilities = UART_CAP_FIFO | UART_CAP_AFE; uart.port.mapbase = pci_resource_start(pdev, 0); uart.port.membase = pcim_iomap(pdev, 0, 0); if (!uart.port.membase) return -ENOMEM; ret = lpss->board->setup(lpss, &uart.port); if (ret) return ret; ret = lpss8250_dma_setup(lpss, &uart); if (ret) goto err_exit; ret = serial8250_register_8250_port(&uart); if (ret < 0) goto err_exit; lpss->line = ret; pci_set_drvdata(pdev, lpss); return 0; err_exit: if (lpss->board->exit) lpss->board->exit(lpss); return ret; } static void lpss8250_remove(struct pci_dev *pdev) { struct lpss8250 *lpss = pci_get_drvdata(pdev); serial8250_unregister_port(lpss->line); if (lpss->board->exit) lpss->board->exit(lpss); } static const struct lpss8250_board byt_board = { .freq = 100000000, .base_baud = 2764800, .setup = byt_serial_setup, }; static const struct lpss8250_board qrk_board = { .freq = 44236800, .base_baud = 2764800, .setup = qrk_serial_setup, .exit = qrk_serial_exit, }; #define LPSS_DEVICE(id, board) { PCI_VDEVICE(INTEL, id), (kernel_ulong_t)&board } static const struct pci_device_id pci_ids[] = { LPSS_DEVICE(PCI_DEVICE_ID_INTEL_QRK_UARTx, qrk_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BYT_UART1, byt_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BYT_UART2, byt_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BSW_UART1, byt_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BSW_UART2, byt_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BDW_UART1, byt_board), LPSS_DEVICE(PCI_DEVICE_ID_INTEL_BDW_UART2, byt_board), { }, }; MODULE_DEVICE_TABLE(pci, pci_ids); static struct pci_driver lpss8250_pci_driver = { .name = "8250_lpss", .id_table = pci_ids, .probe = lpss8250_probe, .remove = lpss8250_remove, }; module_pci_driver(lpss8250_pci_driver); MODULE_AUTHOR("Intel Corporation"); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Intel LPSS UART driver");
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