From: Oleksandr Tyshchenko <oleksandr.tyshche...@globallogic.com> Signed-off-by: Oleksandr Tyshchenko <oleksandr.tyshche...@globallogic.com> Signed-off-by: Iurii Konovalenko <iurii.konovale...@globallogic.com> --- config/arm32.mk | 1 + xen/drivers/char/Makefile | 1 + xen/drivers/char/rcar2-uart.c | 376 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 378 insertions(+) create mode 100644 xen/drivers/char/rcar2-uart.c
diff --git a/config/arm32.mk b/config/arm32.mk index 4f83a63..6ee5173 100644 --- a/config/arm32.mk +++ b/config/arm32.mk @@ -12,6 +12,7 @@ CFLAGS += -marm HAS_PL011 := y HAS_EXYNOS4210 := y HAS_OMAP := y +HAS_RCAR2 := y HAS_NS16550 := y # Use only if calling $(LD) directly. diff --git a/xen/drivers/char/Makefile b/xen/drivers/char/Makefile index 911b788..64428b7 100644 --- a/xen/drivers/char/Makefile +++ b/xen/drivers/char/Makefile @@ -3,6 +3,7 @@ obj-$(HAS_NS16550) += ns16550.o obj-$(HAS_PL011) += pl011.o obj-$(HAS_EXYNOS4210) += exynos4210-uart.o obj-$(HAS_OMAP) += omap-uart.o +obj-$(HAS_RCAR2) += rcar2-uart.o obj-$(HAS_EHCI) += ehci-dbgp.o obj-$(CONFIG_ARM) += dt-uart.o obj-y += serial.o diff --git a/xen/drivers/char/rcar2-uart.c b/xen/drivers/char/rcar2-uart.c new file mode 100644 index 0000000..85d1b17 --- /dev/null +++ b/xen/drivers/char/rcar2-uart.c @@ -0,0 +1,376 @@ +/* + * xen/drivers/char/rcar2-uart.c + * + * Driver for R-Car Gen2 UART. + * + * Oleksandr Tyshchenko <oleksandr.tyshche...@globallogic.com> + * Copyright (C) 2014, Globallogic. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <xen/config.h> +#include <xen/console.h> +#include <xen/errno.h> +#include <xen/serial.h> +#include <xen/init.h> +#include <xen/irq.h> +#include <xen/mm.h> +#include <xen/delay.h> +#include <asm/device.h> +#include <asm/rcar2-uart.h> +#include <asm/io.h> + +#define PARITY_NONE 0 +#define PARITY_EVEN 1 +#define PARITY_ODD 2 + +#define rcar2_readb(uart, off) readb((uart)->regs + (off)) +#define rcar2_writeb(uart, off, val) writeb((val), (uart)->regs + (off)) + +#define rcar2_readw(uart, off) readw((uart)->regs + (off)) +#define rcar2_writew(uart, off, val) writew((val), (uart)->regs + (off)) + +static struct rcar2_uart { + unsigned int baud, clock_hz, data_bits, parity, stop_bits; + unsigned int irq; + char __iomem *regs; + struct irqaction irqaction; + struct vuart_info vuart; + bool_t irq_en; +} rcar2_com = {0}; + +static void rcar2_uart_interrupt(int irq, void *data, struct cpu_user_regs *regs) +{ + struct serial_port *port = data; + struct rcar2_uart *uart = port->uart; + uint16_t status, ctrl; + + ctrl = rcar2_readw(uart, SCIF_SCSCR); + status = rcar2_readw(uart, SCIF_SCFSR) & ~SCFSR_TEND; + /* Ignore next flag if TX Interrupt is disabled */ + if ( !(ctrl & SCSCR_TIE) ) + status &= ~SCFSR_TDFE; + + while ( status != 0 ) + { + /* TX Interrupt */ + if ( status & SCFSR_TDFE ) + { + serial_tx_interrupt(port, regs); + + if ( port->txbufc == port->txbufp ) + { + /* + * There is no data bytes to send. We have to disable + * TX Interrupt to prevent us from getting stuck in the + * interrupt handler + */ + ctrl = rcar2_readw(uart, SCIF_SCSCR); + ctrl &= ~SCSCR_TIE; + rcar2_writew(uart, SCIF_SCSCR, ctrl); + } + } + + /* RX Interrupt */ + if ( status & (SCFSR_RDF | SCFSR_DR) ) + serial_rx_interrupt(port, regs); + + /* Error Interrupt */ + if ( status & SCIF_ERRORS ) + rcar2_writew(uart, SCIF_SCFSR, ~SCIF_ERRORS); + if ( rcar2_readw(uart, SCIF_SCLSR) & SCLSR_ORER ) + rcar2_writew(uart, SCIF_SCLSR, 0); + + status = rcar2_readw(uart, SCIF_SCFSR) & ~SCFSR_TEND; + if ( !(ctrl & SCSCR_TIE) ) + status &= ~SCFSR_TDFE; + } +} + +static void __init rcar2_uart_init_preirq(struct serial_port *port) +{ + struct rcar2_uart *uart = port->uart; + unsigned int divisor; + uint16_t val; + + /* + * Wait until last bit has been transmitted. This is needed for a smooth + * transition when we come from early printk + */ + while ( !(rcar2_readw(uart, SCIF_SCFSR) & SCFSR_TEND) ); + + /* Disable TX/RX parts and all interrupts */ + rcar2_writew(uart, SCIF_SCSCR, 0); + + /* Reset TX/RX FIFOs */ + rcar2_writew(uart, SCIF_SCFCR, SCFCR_RFRST | SCFCR_TFRST); + + /* Clear all errors and flags */ + rcar2_readw(uart, SCIF_SCFSR); + rcar2_writew(uart, SCIF_SCFSR, 0); + rcar2_readw(uart, SCIF_SCLSR); + rcar2_writew(uart, SCIF_SCLSR, 0); + + /* Select Baud rate generator output as a clock source */ + rcar2_writew(uart, SCIF_SCSCR, SCSCR_CKE10); + + /* Setup protocol format and Baud rate, select Asynchronous mode */ + val = 0; + ASSERT( uart->data_bits >= 7 && uart->data_bits <= 8 ); + if ( uart->data_bits == 7 ) + val |= SCSMR_CHR; + else + val &= ~SCSMR_CHR; + + ASSERT( uart->stop_bits >= 1 && uart->stop_bits <= 2 ); + if ( uart->stop_bits == 2 ) + val |= SCSMR_STOP; + else + val &= ~SCSMR_STOP; + + ASSERT( uart->parity >= PARITY_NONE && uart->parity <= PARITY_ODD ); + switch ( uart->parity ) + { + case PARITY_NONE: + val &= ~SCSMR_PE; + break; + + case PARITY_EVEN: + val |= SCSMR_PE; + break; + + case PARITY_ODD: + val |= SCSMR_PE | SCSMR_ODD; + break; + } + rcar2_writew(uart, SCIF_SCSMR, val); + + ASSERT( uart->clock_hz > 0 ); + if ( uart->baud != BAUD_AUTO ) + { + /* Setup desired Baud rate */ + divisor = uart->clock_hz / (uart->baud << 4); + ASSERT( divisor >= 1 && divisor <= (uint16_t)UINT_MAX ); + rcar2_writew(uart, SCIF_DL, (uint16_t)divisor); + /* Selects the frequency divided clock (SC_CLK external input) */ + rcar2_writew(uart, SCIF_CKS, 0); + /* + * TODO: should be uncommented + * udelay(1000000 / uart->baud + 1); + */ + } + else + { + /* Read current Baud rate */ + divisor = rcar2_readw(uart, SCIF_DL); + ASSERT( divisor >= 1 && divisor <= (uint16_t)UINT_MAX ); + uart->baud = uart->clock_hz / (divisor << 4); + } + + /* Setup trigger level for TX/RX FIFOs */ + rcar2_writew(uart, SCIF_SCFCR, SCFCR_RTRG11 | SCFCR_TTRG11); + + /* Enable TX/RX parts */ + rcar2_writew(uart, SCIF_SCSCR, rcar2_readw(uart, SCIF_SCSCR) | + SCSCR_TE | SCSCR_RE); +} + +static void __init rcar2_uart_init_postirq(struct serial_port *port) +{ + struct rcar2_uart *uart = port->uart; + int rc; + + uart->irqaction.handler = rcar2_uart_interrupt; + uart->irqaction.name = "rcar2_uart"; + uart->irqaction.dev_id = port; + + if ( (rc = setup_irq(uart->irq, 0, &uart->irqaction)) != 0 ) + dprintk(XENLOG_ERR, "Failed to allocated rcar2_uart IRQ %d\n", + uart->irq); + + /* Clear all errors */ + if ( rcar2_readw(uart, SCIF_SCFSR) & SCIF_ERRORS ) + rcar2_writew(uart, SCIF_SCFSR, ~SCIF_ERRORS); + if ( rcar2_readw(uart, SCIF_SCLSR) & SCLSR_ORER ) + rcar2_writew(uart, SCIF_SCLSR, 0); + + /* Enable TX/RX and Error Interrupts */ + rcar2_writew(uart, SCIF_SCSCR, rcar2_readw(uart, SCIF_SCSCR) | + SCSCR_TIE | SCSCR_RIE | SCSCR_REIE); + + uart->irq_en = 1; +} + +static void rcar2_uart_suspend(struct serial_port *port) +{ + BUG(); +} + +static void rcar2_uart_resume(struct serial_port *port) +{ + BUG(); +} + +static int rcar2_uart_tx_ready(struct serial_port *port) +{ + struct rcar2_uart *uart = port->uart; + uint16_t cnt; + + /* Check for empty space in TX FIFO */ + if ( !(rcar2_readw(uart, SCIF_SCFSR) & SCFSR_TDFE) ) + return 0; + + /* + * It seems that the Framework has a data bytes to send. + * Enable TX Interrupt disabled from interrupt handler before + */ + if ( uart->irq_en ) + rcar2_writew(uart, SCIF_SCSCR, rcar2_readw(uart, SCIF_SCSCR) | + SCSCR_TIE); + + /* Check number of data bytes stored in TX FIFO */ + cnt = rcar2_readw(uart, SCIF_SCFDR) >> 8; + ASSERT( cnt >= 0 && cnt <= SCIF_FIFO_MAX_SIZE ); + + return (SCIF_FIFO_MAX_SIZE - cnt); +} + +static void rcar2_uart_putc(struct serial_port *port, char c) +{ + struct rcar2_uart *uart = port->uart; + + rcar2_writeb(uart, SCIF_SCFTDR, c); + /* Clear required TX flags */ + rcar2_writew(uart, SCIF_SCFSR, rcar2_readw(uart, SCIF_SCFSR) & + ~(SCFSR_TEND | SCFSR_TDFE)); +} + +static int rcar2_uart_getc(struct serial_port *port, char *pc) +{ + struct rcar2_uart *uart = port->uart; + + /* Check for available data bytes in RX FIFO */ + if ( !(rcar2_readw(uart, SCIF_SCFSR) & (SCFSR_RDF | SCFSR_DR)) ) + return 0; + + *pc = rcar2_readb(uart, SCIF_SCFRDR); + + /* dummy read */ + rcar2_readw(uart, SCIF_SCFSR); + /* Clear required RX flags */ + rcar2_writew(uart, SCIF_SCFSR, ~(SCFSR_RDF | SCFSR_DR)); + + return 1; +} + +static int __init rcar2_uart_irq(struct serial_port *port) +{ + struct rcar2_uart *uart = port->uart; + + return ((uart->irq > 0) ? uart->irq : -1); +} + +static const struct vuart_info *rcar2_vuart_info(struct serial_port *port) +{ + struct rcar2_uart *uart = port->uart; + + return &uart->vuart; +} + +static struct uart_driver __read_mostly rcar2_uart_driver = { + .init_preirq = rcar2_uart_init_preirq, + .init_postirq = rcar2_uart_init_postirq, + .endboot = NULL, + .suspend = rcar2_uart_suspend, + .resume = rcar2_uart_resume, + .tx_ready = rcar2_uart_tx_ready, + .putc = rcar2_uart_putc, + .getc = rcar2_uart_getc, + .irq = rcar2_uart_irq, + .vuart_info = rcar2_vuart_info, +}; + +static int __init rcar2_uart_init(struct dt_device_node *dev, + const void *data) +{ + const char *config = data; + struct rcar2_uart *uart; + int res; + u64 addr, size; + + if ( strcmp(config, "") ) + printk("WARNING: UART configuration is not supported\n"); + + uart = &rcar2_com; + + uart->clock_hz = SCIF_CLK_FREQ; + uart->baud = BAUD_AUTO; + uart->data_bits = 8; + uart->parity = PARITY_NONE; + uart->stop_bits = 1; + + res = dt_device_get_address(dev, 0, &addr, &size); + if ( res ) + { + printk("rcar2-uart: Unable to retrieve the base" + " address of the UART\n"); + return res; + } + + uart->regs = ioremap_attr(addr, size, PAGE_HYPERVISOR_NOCACHE); + if ( !uart->regs ) + { + printk("rcar2-uart: Unable to map the UART memory\n"); + return -ENOMEM; + } + + res = platform_get_irq(dev, 0); + if ( res < 0 ) + { + printk("rcar2-uart: Unable to retrieve the IRQ\n"); + return res; + } + uart->irq = res; + + uart->vuart.base_addr = addr; + uart->vuart.size = size; + uart->vuart.data_off = SCIF_SCFTDR; + uart->vuart.status_off = SCIF_SCFSR; + uart->vuart.status = SCFSR_TDFE; + + /* Register with generic serial driver */ + serial_register_uart(SERHND_DTUART, &rcar2_uart_driver, uart); + + dt_device_set_used_by(dev, DOMID_XEN); + + return 0; +} + +static const char * const rcar2_uart_dt_compat[] __initconst = +{ + "renesas,scif", + NULL +}; + +DT_DEVICE_START(rcar2_uart, "R-Car Gen2 UART", DEVICE_SERIAL) + .compatible = rcar2_uart_dt_compat, + .init = rcar2_uart_init, +DT_DEVICE_END + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * indent-tabs-mode: nil + * End: + */ -- 1.9.1 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel