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author | Greg Kroah-Hartman <gregkh@suse.de> | 2011-01-13 12:10:18 -0800 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-01-13 12:10:18 -0800 |
commit | ab4382d27412e7e3e7c936e8d50d8888dfac3df8 (patch) | |
tree | 51d96dea2431140358784b6b426715f37f74fd53 /drivers/tty/serial/ioc3_serial.c | |
parent | 728674a7e466628df2aeec6d11a2ae1ef968fb67 (diff) | |
download | kernel_samsung_smdk4412-ab4382d27412e7e3e7c936e8d50d8888dfac3df8.zip kernel_samsung_smdk4412-ab4382d27412e7e3e7c936e8d50d8888dfac3df8.tar.gz kernel_samsung_smdk4412-ab4382d27412e7e3e7c936e8d50d8888dfac3df8.tar.bz2 |
tty: move drivers/serial/ to drivers/tty/serial/
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.
This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/serial/ioc3_serial.c')
-rw-r--r-- | drivers/tty/serial/ioc3_serial.c | 2199 |
1 files changed, 2199 insertions, 0 deletions
diff --git a/drivers/tty/serial/ioc3_serial.c b/drivers/tty/serial/ioc3_serial.c new file mode 100644 index 0000000..ee43efc --- /dev/null +++ b/drivers/tty/serial/ioc3_serial.c @@ -0,0 +1,2199 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2005 Silicon Graphics, Inc. All Rights Reserved. + */ + +/* + * This file contains a module version of the ioc3 serial driver. This + * includes all the support functions needed (support functions, etc.) + * and the serial driver itself. + */ +#include <linux/errno.h> +#include <linux/tty.h> +#include <linux/serial.h> +#include <linux/circ_buf.h> +#include <linux/serial_reg.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/serial_core.h> +#include <linux/ioc3.h> +#include <linux/slab.h> + +/* + * Interesting things about the ioc3 + */ + +#define LOGICAL_PORTS 2 /* rs232(0) and rs422(1) */ +#define PORTS_PER_CARD 2 +#define LOGICAL_PORTS_PER_CARD (PORTS_PER_CARD * LOGICAL_PORTS) +#define MAX_CARDS 8 +#define MAX_LOGICAL_PORTS (LOGICAL_PORTS_PER_CARD * MAX_CARDS) + +/* determine given the sio_ir what port it applies to */ +#define GET_PORT_FROM_SIO_IR(_x) (_x & SIO_IR_SA) ? 0 : 1 + + +/* + * we have 2 logical ports (rs232, rs422) for each physical port + * evens are rs232, odds are rs422 + */ +#define GET_PHYSICAL_PORT(_x) ((_x) >> 1) +#define GET_LOGICAL_PORT(_x) ((_x) & 1) +#define IS_PHYSICAL_PORT(_x) !((_x) & 1) +#define IS_RS232(_x) !((_x) & 1) + +static unsigned int Num_of_ioc3_cards; +static unsigned int Submodule_slot; + +/* defining this will get you LOTS of great debug info */ +//#define DEBUG_INTERRUPTS +#define DPRINT_CONFIG(_x...) ; +//#define DPRINT_CONFIG(_x...) printk _x +#define NOT_PROGRESS() ; +//#define NOT_PROGRESS() printk("%s : fails %d\n", __func__, __LINE__) + +/* number of characters we want to transmit to the lower level at a time */ +#define MAX_CHARS 256 +#define FIFO_SIZE (MAX_CHARS-1) /* it's a uchar */ + +/* Device name we're using */ +#define DEVICE_NAME "ttySIOC" +#define DEVICE_MAJOR 204 +#define DEVICE_MINOR 116 + +/* flags for next_char_state */ +#define NCS_BREAK 0x1 +#define NCS_PARITY 0x2 +#define NCS_FRAMING 0x4 +#define NCS_OVERRUN 0x8 + +/* cause we need SOME parameters ... */ +#define MIN_BAUD_SUPPORTED 1200 +#define MAX_BAUD_SUPPORTED 115200 + +/* protocol types supported */ +#define PROTO_RS232 0 +#define PROTO_RS422 1 + +/* Notification types */ +#define N_DATA_READY 0x01 +#define N_OUTPUT_LOWAT 0x02 +#define N_BREAK 0x04 +#define N_PARITY_ERROR 0x08 +#define N_FRAMING_ERROR 0x10 +#define N_OVERRUN_ERROR 0x20 +#define N_DDCD 0x40 +#define N_DCTS 0x80 + +#define N_ALL_INPUT (N_DATA_READY | N_BREAK \ + | N_PARITY_ERROR | N_FRAMING_ERROR \ + | N_OVERRUN_ERROR | N_DDCD | N_DCTS) + +#define N_ALL_OUTPUT N_OUTPUT_LOWAT + +#define N_ALL_ERRORS (N_PARITY_ERROR | N_FRAMING_ERROR \ + | N_OVERRUN_ERROR) + +#define N_ALL (N_DATA_READY | N_OUTPUT_LOWAT | N_BREAK \ + | N_PARITY_ERROR | N_FRAMING_ERROR \ + | N_OVERRUN_ERROR | N_DDCD | N_DCTS) + +#define SER_CLK_SPEED(prediv) ((22000000 << 1) / prediv) +#define SER_DIVISOR(x, clk) (((clk) + (x) * 8) / ((x) * 16)) +#define DIVISOR_TO_BAUD(div, clk) ((clk) / 16 / (div)) + +/* Some masks */ +#define LCR_MASK_BITS_CHAR (UART_LCR_WLEN5 | UART_LCR_WLEN6 \ + | UART_LCR_WLEN7 | UART_LCR_WLEN8) +#define LCR_MASK_STOP_BITS (UART_LCR_STOP) + +#define PENDING(_a, _p) (readl(&(_p)->vma->sio_ir) & (_a)->ic_enable) + +#define RING_BUF_SIZE 4096 +#define BUF_SIZE_BIT SBBR_L_SIZE +#define PROD_CONS_MASK PROD_CONS_PTR_4K + +#define TOTAL_RING_BUF_SIZE (RING_BUF_SIZE * 4) + +/* driver specific - one per card */ +struct ioc3_card { + struct { + /* uart ports are allocated here */ + struct uart_port icp_uart_port[LOGICAL_PORTS]; + /* the ioc3_port used for this port */ + struct ioc3_port *icp_port; + } ic_port[PORTS_PER_CARD]; + /* currently enabled interrupts */ + uint32_t ic_enable; +}; + +/* Local port info for each IOC3 serial port */ +struct ioc3_port { + /* handy reference material */ + struct uart_port *ip_port; + struct ioc3_card *ip_card; + struct ioc3_driver_data *ip_idd; + struct ioc3_submodule *ip_is; + + /* pci mem addresses for this port */ + struct ioc3_serialregs __iomem *ip_serial_regs; + struct ioc3_uartregs __iomem *ip_uart_regs; + + /* Ring buffer page for this port */ + dma_addr_t ip_dma_ringbuf; + /* vaddr of ring buffer */ + struct ring_buffer *ip_cpu_ringbuf; + + /* Rings for this port */ + struct ring *ip_inring; + struct ring *ip_outring; + + /* Hook to port specific values */ + struct port_hooks *ip_hooks; + + spinlock_t ip_lock; + + /* Various rx/tx parameters */ + int ip_baud; + int ip_tx_lowat; + int ip_rx_timeout; + + /* Copy of notification bits */ + int ip_notify; + + /* Shadow copies of various registers so we don't need to PIO + * read them constantly + */ + uint32_t ip_sscr; + uint32_t ip_tx_prod; + uint32_t ip_rx_cons; + unsigned char ip_flags; +}; + +/* tx low water mark. We need to notify the driver whenever tx is getting + * close to empty so it can refill the tx buffer and keep things going. + * Let's assume that if we interrupt 1 ms before the tx goes idle, we'll + * have no trouble getting in more chars in time (I certainly hope so). + */ +#define TX_LOWAT_LATENCY 1000 +#define TX_LOWAT_HZ (1000000 / TX_LOWAT_LATENCY) +#define TX_LOWAT_CHARS(baud) (baud / 10 / TX_LOWAT_HZ) + +/* Flags per port */ +#define INPUT_HIGH 0x01 + /* used to signify that we have turned off the rx_high + * temporarily - we need to drain the fifo and don't + * want to get blasted with interrupts. + */ +#define DCD_ON 0x02 + /* DCD state is on */ +#define LOWAT_WRITTEN 0x04 +#define READ_ABORTED 0x08 + /* the read was aborted - used to avaoid infinate looping + * in the interrupt handler + */ +#define INPUT_ENABLE 0x10 + +/* Since each port has different register offsets and bitmasks + * for everything, we'll store those that we need in tables so we + * don't have to be constantly checking the port we are dealing with. + */ +struct port_hooks { + uint32_t intr_delta_dcd; + uint32_t intr_delta_cts; + uint32_t intr_tx_mt; + uint32_t intr_rx_timer; + uint32_t intr_rx_high; + uint32_t intr_tx_explicit; + uint32_t intr_clear; + uint32_t intr_all; + char rs422_select_pin; +}; + +static struct port_hooks hooks_array[PORTS_PER_CARD] = { + /* values for port A */ + { + .intr_delta_dcd = SIO_IR_SA_DELTA_DCD, + .intr_delta_cts = SIO_IR_SA_DELTA_CTS, + .intr_tx_mt = SIO_IR_SA_TX_MT, + .intr_rx_timer = SIO_IR_SA_RX_TIMER, + .intr_rx_high = SIO_IR_SA_RX_HIGH, + .intr_tx_explicit = SIO_IR_SA_TX_EXPLICIT, + .intr_clear = (SIO_IR_SA_TX_MT | SIO_IR_SA_RX_FULL + | SIO_IR_SA_RX_HIGH + | SIO_IR_SA_RX_TIMER + | SIO_IR_SA_DELTA_DCD + | SIO_IR_SA_DELTA_CTS + | SIO_IR_SA_INT + | SIO_IR_SA_TX_EXPLICIT + | SIO_IR_SA_MEMERR), + .intr_all = SIO_IR_SA, + .rs422_select_pin = GPPR_UARTA_MODESEL_PIN, + }, + + /* values for port B */ + { + .intr_delta_dcd = SIO_IR_SB_DELTA_DCD, + .intr_delta_cts = SIO_IR_SB_DELTA_CTS, + .intr_tx_mt = SIO_IR_SB_TX_MT, + .intr_rx_timer = SIO_IR_SB_RX_TIMER, + .intr_rx_high = SIO_IR_SB_RX_HIGH, + .intr_tx_explicit = SIO_IR_SB_TX_EXPLICIT, + .intr_clear = (SIO_IR_SB_TX_MT | SIO_IR_SB_RX_FULL + | SIO_IR_SB_RX_HIGH + | SIO_IR_SB_RX_TIMER + | SIO_IR_SB_DELTA_DCD + | SIO_IR_SB_DELTA_CTS + | SIO_IR_SB_INT + | SIO_IR_SB_TX_EXPLICIT + | SIO_IR_SB_MEMERR), + .intr_all = SIO_IR_SB, + .rs422_select_pin = GPPR_UARTB_MODESEL_PIN, + } +}; + +struct ring_entry { + union { + struct { + uint32_t alldata; + uint32_t allsc; + } all; + struct { + char data[4]; /* data bytes */ + char sc[4]; /* status/control */ + } s; + } u; +}; + +/* Test the valid bits in any of the 4 sc chars using "allsc" member */ +#define RING_ANY_VALID \ + ((uint32_t)(RXSB_MODEM_VALID | RXSB_DATA_VALID) * 0x01010101) + +#define ring_sc u.s.sc +#define ring_data u.s.data +#define ring_allsc u.all.allsc + +/* Number of entries per ring buffer. */ +#define ENTRIES_PER_RING (RING_BUF_SIZE / (int) sizeof(struct ring_entry)) + +/* An individual ring */ +struct ring { + struct ring_entry entries[ENTRIES_PER_RING]; +}; + +/* The whole enchilada */ +struct ring_buffer { + struct ring TX_A; + struct ring RX_A; + struct ring TX_B; + struct ring RX_B; +}; + +/* Get a ring from a port struct */ +#define RING(_p, _wh) &(((struct ring_buffer *)((_p)->ip_cpu_ringbuf))->_wh) + +/* for Infinite loop detection */ +#define MAXITER 10000000 + + +/** + * set_baud - Baud rate setting code + * @port: port to set + * @baud: baud rate to use + */ +static int set_baud(struct ioc3_port *port, int baud) +{ + int divisor; + int actual_baud; + int diff; + int lcr, prediv; + struct ioc3_uartregs __iomem *uart; + + for (prediv = 6; prediv < 64; prediv++) { + divisor = SER_DIVISOR(baud, SER_CLK_SPEED(prediv)); + if (!divisor) + continue; /* invalid divisor */ + actual_baud = DIVISOR_TO_BAUD(divisor, SER_CLK_SPEED(prediv)); + + diff = actual_baud - baud; + if (diff < 0) + diff = -diff; + + /* if we're within 1% we've found a match */ + if (diff * 100 <= actual_baud) + break; + } + + /* if the above loop completed, we didn't match + * the baud rate. give up. + */ + if (prediv == 64) { + NOT_PROGRESS(); + return 1; + } + + uart = port->ip_uart_regs; + lcr = readb(&uart->iu_lcr); + + writeb(lcr | UART_LCR_DLAB, &uart->iu_lcr); + writeb((unsigned char)divisor, &uart->iu_dll); + writeb((unsigned char)(divisor >> 8), &uart->iu_dlm); + writeb((unsigned char)prediv, &uart->iu_scr); + writeb((unsigned char)lcr, &uart->iu_lcr); + + return 0; +} + +/** + * get_ioc3_port - given a uart port, return the control structure + * @the_port: uart port to find + */ +static struct ioc3_port *get_ioc3_port(struct uart_port *the_port) +{ + struct ioc3_driver_data *idd = dev_get_drvdata(the_port->dev); + struct ioc3_card *card_ptr = idd->data[Submodule_slot]; + int ii, jj; + + if (!card_ptr) { + NOT_PROGRESS(); + return NULL; + } + for (ii = 0; ii < PORTS_PER_CARD; ii++) { + for (jj = 0; jj < LOGICAL_PORTS; jj++) { + if (the_port == &card_ptr->ic_port[ii].icp_uart_port[jj]) + return card_ptr->ic_port[ii].icp_port; + } + } + NOT_PROGRESS(); + return NULL; +} + +/** + * port_init - Initialize the sio and ioc3 hardware for a given port + * called per port from attach... + * @port: port to initialize + */ +static int inline port_init(struct ioc3_port *port) +{ + uint32_t sio_cr; + struct port_hooks *hooks = port->ip_hooks; + struct ioc3_uartregs __iomem *uart; + int reset_loop_counter = 0xfffff; + struct ioc3_driver_data *idd = port->ip_idd; + + /* Idle the IOC3 serial interface */ + writel(SSCR_RESET, &port->ip_serial_regs->sscr); + + /* Wait until any pending bus activity for this port has ceased */ + do { + sio_cr = readl(&idd->vma->sio_cr); + if (reset_loop_counter-- <= 0) { + printk(KERN_WARNING + "IOC3 unable to come out of reset" + " scr 0x%x\n", sio_cr); + return -1; + } + } while (!(sio_cr & SIO_CR_ARB_DIAG_IDLE) && + (((sio_cr &= SIO_CR_ARB_DIAG) == SIO_CR_ARB_DIAG_TXA) + || sio_cr == SIO_CR_ARB_DIAG_TXB + || sio_cr == SIO_CR_ARB_DIAG_RXA + || sio_cr == SIO_CR_ARB_DIAG_RXB)); + + /* Finish reset sequence */ + writel(0, &port->ip_serial_regs->sscr); + + /* Once RESET is done, reload cached tx_prod and rx_cons values + * and set rings to empty by making prod == cons + */ + port->ip_tx_prod = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK; + writel(port->ip_tx_prod, &port->ip_serial_regs->stpir); + port->ip_rx_cons = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK; + writel(port->ip_rx_cons | SRCIR_ARM, &port->ip_serial_regs->srcir); + + /* Disable interrupts for this 16550 */ + uart = port->ip_uart_regs; + writeb(0, &uart->iu_lcr); + writeb(0, &uart->iu_ier); + + /* Set the default baud */ + set_baud(port, port->ip_baud); + + /* Set line control to 8 bits no parity */ + writeb(UART_LCR_WLEN8 | 0, &uart->iu_lcr); + /* UART_LCR_STOP == 1 stop */ + + /* Enable the FIFOs */ + writeb(UART_FCR_ENABLE_FIFO, &uart->iu_fcr); + /* then reset 16550 FIFOs */ + writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, + &uart->iu_fcr); + + /* Clear modem control register */ + writeb(0, &uart->iu_mcr); + + /* Clear deltas in modem status register */ + writel(0, &port->ip_serial_regs->shadow); + + /* Only do this once per port pair */ + if (port->ip_hooks == &hooks_array[0]) { + unsigned long ring_pci_addr; + uint32_t __iomem *sbbr_l, *sbbr_h; + + sbbr_l = &idd->vma->sbbr_l; + sbbr_h = &idd->vma->sbbr_h; + ring_pci_addr = (unsigned long __iomem)port->ip_dma_ringbuf; + DPRINT_CONFIG(("%s: ring_pci_addr 0x%p\n", + __func__, (void *)ring_pci_addr)); + + writel((unsigned int)((uint64_t) ring_pci_addr >> 32), sbbr_h); + writel((unsigned int)ring_pci_addr | BUF_SIZE_BIT, sbbr_l); + } + + /* Set the receive timeout value to 10 msec */ + writel(SRTR_HZ / 100, &port->ip_serial_regs->srtr); + + /* Set rx threshold, enable DMA */ + /* Set high water mark at 3/4 of full ring */ + port->ip_sscr = (ENTRIES_PER_RING * 3 / 4); + + /* uart experiences pauses at high baud rate reducing actual + * throughput by 10% or so unless we enable high speed polling + * XXX when this hardware bug is resolved we should revert to + * normal polling speed + */ + port->ip_sscr |= SSCR_HIGH_SPD; + + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + + /* Disable and clear all serial related interrupt bits */ + port->ip_card->ic_enable &= ~hooks->intr_clear; + ioc3_disable(port->ip_is, idd, hooks->intr_clear); + ioc3_ack(port->ip_is, idd, hooks->intr_clear); + return 0; +} + +/** + * enable_intrs - enable interrupts + * @port: port to enable + * @mask: mask to use + */ +static void enable_intrs(struct ioc3_port *port, uint32_t mask) +{ + if ((port->ip_card->ic_enable & mask) != mask) { + port->ip_card->ic_enable |= mask; + ioc3_enable(port->ip_is, port->ip_idd, mask); + } +} + +/** + * local_open - local open a port + * @port: port to open + */ +static inline int local_open(struct ioc3_port *port) +{ + int spiniter = 0; + + port->ip_flags = INPUT_ENABLE; + + /* Pause the DMA interface if necessary */ + if (port->ip_sscr & SSCR_DMA_EN) { + writel(port->ip_sscr | SSCR_DMA_PAUSE, + &port->ip_serial_regs->sscr); + while ((readl(&port->ip_serial_regs->sscr) + & SSCR_PAUSE_STATE) == 0) { + spiniter++; + if (spiniter > MAXITER) { + NOT_PROGRESS(); + return -1; + } + } + } + + /* Reset the input fifo. If the uart received chars while the port + * was closed and DMA is not enabled, the uart may have a bunch of + * chars hanging around in its rx fifo which will not be discarded + * by rclr in the upper layer. We must get rid of them here. + */ + writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR, + &port->ip_uart_regs->iu_fcr); + + writeb(UART_LCR_WLEN8, &port->ip_uart_regs->iu_lcr); + /* UART_LCR_STOP == 1 stop */ + + /* Re-enable DMA, set default threshold to intr whenever there is + * data available. + */ + port->ip_sscr &= ~SSCR_RX_THRESHOLD; + port->ip_sscr |= 1; /* default threshold */ + + /* Plug in the new sscr. This implicitly clears the DMA_PAUSE + * flag if it was set above + */ + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + port->ip_tx_lowat = 1; + return 0; +} + +/** + * set_rx_timeout - Set rx timeout and threshold values. + * @port: port to use + * @timeout: timeout value in ticks + */ +static inline int set_rx_timeout(struct ioc3_port *port, int timeout) +{ + int threshold; + + port->ip_rx_timeout = timeout; + + /* Timeout is in ticks. Let's figure out how many chars we + * can receive at the current baud rate in that interval + * and set the rx threshold to that amount. There are 4 chars + * per ring entry, so we'll divide the number of chars that will + * arrive in timeout by 4. + * So .... timeout * baud / 10 / HZ / 4, with HZ = 100. + */ + threshold = timeout * port->ip_baud / 4000; + if (threshold == 0) + threshold = 1; /* otherwise we'll intr all the time! */ + + if ((unsigned)threshold > (unsigned)SSCR_RX_THRESHOLD) + return 1; + + port->ip_sscr &= ~SSCR_RX_THRESHOLD; + port->ip_sscr |= threshold; + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + + /* Now set the rx timeout to the given value + * again timeout * SRTR_HZ / HZ + */ + timeout = timeout * SRTR_HZ / 100; + if (timeout > SRTR_CNT) + timeout = SRTR_CNT; + writel(timeout, &port->ip_serial_regs->srtr); + return 0; +} + +/** + * config_port - config the hardware + * @port: port to config + * @baud: baud rate for the port + * @byte_size: data size + * @stop_bits: number of stop bits + * @parenb: parity enable ? + * @parodd: odd parity ? + */ +static inline int +config_port(struct ioc3_port *port, + int baud, int byte_size, int stop_bits, int parenb, int parodd) +{ + char lcr, sizebits; + int spiniter = 0; + + DPRINT_CONFIG(("%s: line %d baud %d byte_size %d stop %d parenb %d " + "parodd %d\n", + __func__, ((struct uart_port *)port->ip_port)->line, + baud, byte_size, stop_bits, parenb, parodd)); + + if (set_baud(port, baud)) + return 1; + + switch (byte_size) { + case 5: + sizebits = UART_LCR_WLEN5; + break; + case 6: + sizebits = UART_LCR_WLEN6; + break; + case 7: + sizebits = UART_LCR_WLEN7; + break; + case 8: + sizebits = UART_LCR_WLEN8; + break; + default: + return 1; + } + + /* Pause the DMA interface if necessary */ + if (port->ip_sscr & SSCR_DMA_EN) { + writel(port->ip_sscr | SSCR_DMA_PAUSE, + &port->ip_serial_regs->sscr); + while ((readl(&port->ip_serial_regs->sscr) + & SSCR_PAUSE_STATE) == 0) { + spiniter++; + if (spiniter > MAXITER) + return -1; + } + } + + /* Clear relevant fields in lcr */ + lcr = readb(&port->ip_uart_regs->iu_lcr); + lcr &= ~(LCR_MASK_BITS_CHAR | UART_LCR_EPAR | + UART_LCR_PARITY | LCR_MASK_STOP_BITS); + + /* Set byte size in lcr */ + lcr |= sizebits; + + /* Set parity */ + if (parenb) { + lcr |= UART_LCR_PARITY; + if (!parodd) + lcr |= UART_LCR_EPAR; + } + + /* Set stop bits */ + if (stop_bits) + lcr |= UART_LCR_STOP /* 2 stop bits */ ; + + writeb(lcr, &port->ip_uart_regs->iu_lcr); + + /* Re-enable the DMA interface if necessary */ + if (port->ip_sscr & SSCR_DMA_EN) { + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + } + port->ip_baud = baud; + + /* When we get within this number of ring entries of filling the + * entire ring on tx, place an EXPLICIT intr to generate a lowat + * notification when output has drained. + */ + port->ip_tx_lowat = (TX_LOWAT_CHARS(baud) + 3) / 4; + if (port->ip_tx_lowat == 0) + port->ip_tx_lowat = 1; + + set_rx_timeout(port, 2); + return 0; +} + +/** + * do_write - Write bytes to the port. Returns the number of bytes + * actually written. Called from transmit_chars + * @port: port to use + * @buf: the stuff to write + * @len: how many bytes in 'buf' + */ +static inline int do_write(struct ioc3_port *port, char *buf, int len) +{ + int prod_ptr, cons_ptr, total = 0; + struct ring *outring; + struct ring_entry *entry; + struct port_hooks *hooks = port->ip_hooks; + + BUG_ON(!(len >= 0)); + + prod_ptr = port->ip_tx_prod; + cons_ptr = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK; + outring = port->ip_outring; + + /* Maintain a 1-entry red-zone. The ring buffer is full when + * (cons - prod) % ring_size is 1. Rather than do this subtraction + * in the body of the loop, I'll do it now. + */ + cons_ptr = (cons_ptr - (int)sizeof(struct ring_entry)) & PROD_CONS_MASK; + + /* Stuff the bytes into the output */ + while ((prod_ptr != cons_ptr) && (len > 0)) { + int xx; + + /* Get 4 bytes (one ring entry) at a time */ + entry = (struct ring_entry *)((caddr_t) outring + prod_ptr); + + /* Invalidate all entries */ + entry->ring_allsc = 0; + + /* Copy in some bytes */ + for (xx = 0; (xx < 4) && (len > 0); xx++) { + entry->ring_data[xx] = *buf++; + entry->ring_sc[xx] = TXCB_VALID; + len--; + total++; + } + + /* If we are within some small threshold of filling up the + * entire ring buffer, we must place an EXPLICIT intr here + * to generate a lowat interrupt in case we subsequently + * really do fill up the ring and the caller goes to sleep. + * No need to place more than one though. + */ + if (!(port->ip_flags & LOWAT_WRITTEN) && + ((cons_ptr - prod_ptr) & PROD_CONS_MASK) + <= port->ip_tx_lowat * (int)sizeof(struct ring_entry)) { + port->ip_flags |= LOWAT_WRITTEN; + entry->ring_sc[0] |= TXCB_INT_WHEN_DONE; + } + + /* Go on to next entry */ + prod_ptr += sizeof(struct ring_entry); + prod_ptr &= PROD_CONS_MASK; + } + + /* If we sent something, start DMA if necessary */ + if (total > 0 && !(port->ip_sscr & SSCR_DMA_EN)) { + port->ip_sscr |= SSCR_DMA_EN; + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + } + + /* Store the new producer pointer. If tx is disabled, we stuff the + * data into the ring buffer, but we don't actually start tx. + */ + if (!uart_tx_stopped(port->ip_port)) { + writel(prod_ptr, &port->ip_serial_regs->stpir); + + /* If we are now transmitting, enable tx_mt interrupt so we + * can disable DMA if necessary when the tx finishes. + */ + if (total > 0) + enable_intrs(port, hooks->intr_tx_mt); + } + port->ip_tx_prod = prod_ptr; + + return total; +} + +/** + * disable_intrs - disable interrupts + * @port: port to enable + * @mask: mask to use + */ +static inline void disable_intrs(struct ioc3_port *port, uint32_t mask) +{ + if (port->ip_card->ic_enable & mask) { + ioc3_disable(port->ip_is, port->ip_idd, mask); + port->ip_card->ic_enable &= ~mask; + } +} + +/** + * set_notification - Modify event notification + * @port: port to use + * @mask: events mask + * @set_on: set ? + */ +static int set_notification(struct ioc3_port *port, int mask, int set_on) +{ + struct port_hooks *hooks = port->ip_hooks; + uint32_t intrbits, sscrbits; + + BUG_ON(!mask); + + intrbits = sscrbits = 0; + + if (mask & N_DATA_READY) + intrbits |= (hooks->intr_rx_timer | hooks->intr_rx_high); + if (mask & N_OUTPUT_LOWAT) + intrbits |= hooks->intr_tx_explicit; + if (mask & N_DDCD) { + intrbits |= hooks->intr_delta_dcd; + sscrbits |= SSCR_RX_RING_DCD; + } + if (mask & N_DCTS) + intrbits |= hooks->intr_delta_cts; + + if (set_on) { + enable_intrs(port, intrbits); + port->ip_notify |= mask; + port->ip_sscr |= sscrbits; + } else { + disable_intrs(port, intrbits); + port->ip_notify &= ~mask; + port->ip_sscr &= ~sscrbits; + } + + /* We require DMA if either DATA_READY or DDCD notification is + * currently requested. If neither of these is requested and + * there is currently no tx in progress, DMA may be disabled. + */ + if (port->ip_notify & (N_DATA_READY | N_DDCD)) + port->ip_sscr |= SSCR_DMA_EN; + else if (!(port->ip_card->ic_enable & hooks->intr_tx_mt)) + port->ip_sscr &= ~SSCR_DMA_EN; + + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + return 0; +} + +/** + * set_mcr - set the master control reg + * @the_port: port to use + * @mask1: mcr mask + * @mask2: shadow mask + */ +static inline int set_mcr(struct uart_port *the_port, + int mask1, int mask2) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + uint32_t shadow; + int spiniter = 0; + char mcr; + + if (!port) + return -1; + + /* Pause the DMA interface if necessary */ + if (port->ip_sscr & SSCR_DMA_EN) { + writel(port->ip_sscr | SSCR_DMA_PAUSE, + &port->ip_serial_regs->sscr); + while ((readl(&port->ip_serial_regs->sscr) + & SSCR_PAUSE_STATE) == 0) { + spiniter++; + if (spiniter > MAXITER) + return -1; + } + } + shadow = readl(&port->ip_serial_regs->shadow); + mcr = (shadow & 0xff000000) >> 24; + + /* Set new value */ + mcr |= mask1; + shadow |= mask2; + writeb(mcr, &port->ip_uart_regs->iu_mcr); + writel(shadow, &port->ip_serial_regs->shadow); + + /* Re-enable the DMA interface if necessary */ + if (port->ip_sscr & SSCR_DMA_EN) { + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + } + return 0; +} + +/** + * ioc3_set_proto - set the protocol for the port + * @port: port to use + * @proto: protocol to use + */ +static int ioc3_set_proto(struct ioc3_port *port, int proto) +{ + struct port_hooks *hooks = port->ip_hooks; + + switch (proto) { + default: + case PROTO_RS232: + /* Clear the appropriate GIO pin */ + DPRINT_CONFIG(("%s: rs232\n", __func__)); + writel(0, (&port->ip_idd->vma->gppr[0] + + hooks->rs422_select_pin)); + break; + + case PROTO_RS422: + /* Set the appropriate GIO pin */ + DPRINT_CONFIG(("%s: rs422\n", __func__)); + writel(1, (&port->ip_idd->vma->gppr[0] + + hooks->rs422_select_pin)); + break; + } + return 0; +} + +/** + * transmit_chars - upper level write, called with the_port->lock + * @the_port: port to write + */ +static void transmit_chars(struct uart_port *the_port) +{ + int xmit_count, tail, head; + int result; + char *start; + struct tty_struct *tty; + struct ioc3_port *port = get_ioc3_port(the_port); + struct uart_state *state; + + if (!the_port) + return; + if (!port) + return; + + state = the_port->state; + tty = state->port.tty; + + if (uart_circ_empty(&state->xmit) || uart_tx_stopped(the_port)) { + /* Nothing to do or hw stopped */ + set_notification(port, N_ALL_OUTPUT, 0); + return; + } + + head = state->xmit.head; + tail = state->xmit.tail; + start = (char *)&state->xmit.buf[tail]; + + /* write out all the data or until the end of the buffer */ + xmit_count = (head < tail) ? (UART_XMIT_SIZE - tail) : (head - tail); + if (xmit_count > 0) { + result = do_write(port, start, xmit_count); + if (result > 0) { + /* booking */ + xmit_count -= result; + the_port->icount.tx += result; + /* advance the pointers */ + tail += result; + tail &= UART_XMIT_SIZE - 1; + state->xmit.tail = tail; + start = (char *)&state->xmit.buf[tail]; + } + } + if (uart_circ_chars_pending(&state->xmit) < WAKEUP_CHARS) + uart_write_wakeup(the_port); + + if (uart_circ_empty(&state->xmit)) { + set_notification(port, N_OUTPUT_LOWAT, 0); + } else { + set_notification(port, N_OUTPUT_LOWAT, 1); + } +} + +/** + * ioc3_change_speed - change the speed of the port + * @the_port: port to change + * @new_termios: new termios settings + * @old_termios: old termios settings + */ +static void +ioc3_change_speed(struct uart_port *the_port, + struct ktermios *new_termios, struct ktermios *old_termios) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + unsigned int cflag, iflag; + int baud; + int new_parity = 0, new_parity_enable = 0, new_stop = 0, new_data = 8; + struct uart_state *state = the_port->state; + + cflag = new_termios->c_cflag; + iflag = new_termios->c_iflag; + + switch (cflag & CSIZE) { + case CS5: + new_data = 5; + break; + case CS6: + new_data = 6; + break; + case CS7: + new_data = 7; + break; + case CS8: + new_data = 8; + break; + default: + /* cuz we always need a default ... */ + new_data = 5; + break; + } + if (cflag & CSTOPB) { + new_stop = 1; + } + if (cflag & PARENB) { + new_parity_enable = 1; + if (cflag & PARODD) + new_parity = 1; + } + baud = uart_get_baud_rate(the_port, new_termios, old_termios, + MIN_BAUD_SUPPORTED, MAX_BAUD_SUPPORTED); + DPRINT_CONFIG(("%s: returned baud %d for line %d\n", __func__, baud, + the_port->line)); + + if (!the_port->fifosize) + the_port->fifosize = FIFO_SIZE; + uart_update_timeout(the_port, cflag, baud); + + the_port->ignore_status_mask = N_ALL_INPUT; + + state->port.tty->low_latency = 1; + + if (iflag & IGNPAR) + the_port->ignore_status_mask &= ~(N_PARITY_ERROR + | N_FRAMING_ERROR); + if (iflag & IGNBRK) { + the_port->ignore_status_mask &= ~N_BREAK; + if (iflag & IGNPAR) + the_port->ignore_status_mask &= ~N_OVERRUN_ERROR; + } + if (!(cflag & CREAD)) { + /* ignore everything */ + the_port->ignore_status_mask &= ~N_DATA_READY; + } + + if (cflag & CRTSCTS) { + /* enable hardware flow control */ + port->ip_sscr |= SSCR_HFC_EN; + } + else { + /* disable hardware flow control */ + port->ip_sscr &= ~SSCR_HFC_EN; + } + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + + /* Set the configuration and proper notification call */ + DPRINT_CONFIG(("%s : port 0x%p line %d cflag 0%o " + "config_port(baud %d data %d stop %d penable %d " + " parity %d), notification 0x%x\n", + __func__, (void *)port, the_port->line, cflag, baud, + new_data, new_stop, new_parity_enable, new_parity, + the_port->ignore_status_mask)); + + if ((config_port(port, baud, /* baud */ + new_data, /* byte size */ + new_stop, /* stop bits */ + new_parity_enable, /* set parity */ + new_parity)) >= 0) { /* parity 1==odd */ + set_notification(port, the_port->ignore_status_mask, 1); + } +} + +/** + * ic3_startup_local - Start up the serial port - returns >= 0 if no errors + * @the_port: Port to operate on + */ +static inline int ic3_startup_local(struct uart_port *the_port) +{ + struct ioc3_port *port; + + if (!the_port) { + NOT_PROGRESS(); + return -1; + } + + port = get_ioc3_port(the_port); + if (!port) { + NOT_PROGRESS(); + return -1; + } + + local_open(port); + + /* set the protocol */ + ioc3_set_proto(port, IS_RS232(the_port->line) ? PROTO_RS232 : + PROTO_RS422); + return 0; +} + +/* + * ioc3_cb_output_lowat - called when the output low water mark is hit + * @port: port to output + */ +static void ioc3_cb_output_lowat(struct ioc3_port *port) +{ + unsigned long pflags; + + /* the_port->lock is set on the call here */ + if (port->ip_port) { + spin_lock_irqsave(&port->ip_port->lock, pflags); + transmit_chars(port->ip_port); + spin_unlock_irqrestore(&port->ip_port->lock, pflags); + } +} + +/* + * ioc3_cb_post_ncs - called for some basic errors + * @port: port to use + * @ncs: event + */ +static void ioc3_cb_post_ncs(struct uart_port *the_port, int ncs) +{ + struct uart_icount *icount; + + icount = &the_port->icount; + + if (ncs & NCS_BREAK) + icount->brk++; + if (ncs & NCS_FRAMING) + icount->frame++; + if (ncs & NCS_OVERRUN) + icount->overrun++; + if (ncs & NCS_PARITY) + icount->parity++; +} + +/** + * do_read - Read in bytes from the port. Return the number of bytes + * actually read. + * @the_port: port to use + * @buf: place to put the stuff we read + * @len: how big 'buf' is + */ + +static inline int do_read(struct uart_port *the_port, char *buf, int len) +{ + int prod_ptr, cons_ptr, total; + struct ioc3_port *port = get_ioc3_port(the_port); + struct ring *inring; + struct ring_entry *entry; + struct port_hooks *hooks = port->ip_hooks; + int byte_num; + char *sc; + int loop_counter; + + BUG_ON(!(len >= 0)); + BUG_ON(!port); + + /* There is a nasty timing issue in the IOC3. When the rx_timer + * expires or the rx_high condition arises, we take an interrupt. + * At some point while servicing the interrupt, we read bytes from + * the ring buffer and re-arm the rx_timer. However the rx_timer is + * not started until the first byte is received *after* it is armed, + * and any bytes pending in the rx construction buffers are not drained + * to memory until either there are 4 bytes available or the rx_timer + * expires. This leads to a potential situation where data is left + * in the construction buffers forever - 1 to 3 bytes were received + * after the interrupt was generated but before the rx_timer was + * re-armed. At that point as long as no subsequent bytes are received + * the timer will never be started and the bytes will remain in the + * construction buffer forever. The solution is to execute a DRAIN + * command after rearming the timer. This way any bytes received before + * the DRAIN will be drained to memory, and any bytes received after + * the DRAIN will start the TIMER and be drained when it expires. + * Luckily, this only needs to be done when the DMA buffer is empty + * since there is no requirement that this function return all + * available data as long as it returns some. + */ + /* Re-arm the timer */ + + writel(port->ip_rx_cons | SRCIR_ARM, &port->ip_serial_regs->srcir); + + prod_ptr = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK; + cons_ptr = port->ip_rx_cons; + + if (prod_ptr == cons_ptr) { + int reset_dma = 0; + + /* Input buffer appears empty, do a flush. */ + + /* DMA must be enabled for this to work. */ + if (!(port->ip_sscr & SSCR_DMA_EN)) { + port->ip_sscr |= SSCR_DMA_EN; + reset_dma = 1; + } + + /* Potential race condition: we must reload the srpir after + * issuing the drain command, otherwise we could think the rx + * buffer is empty, then take a very long interrupt, and when + * we come back it's full and we wait forever for the drain to + * complete. + */ + writel(port->ip_sscr | SSCR_RX_DRAIN, + &port->ip_serial_regs->sscr); + prod_ptr = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK; + + /* We must not wait for the DRAIN to complete unless there are + * at least 8 bytes (2 ring entries) available to receive the + * data otherwise the DRAIN will never complete and we'll + * deadlock here. + * In fact, to make things easier, I'll just ignore the flush if + * there is any data at all now available. + */ + if (prod_ptr == cons_ptr) { + loop_counter = 0; + while (readl(&port->ip_serial_regs->sscr) & + SSCR_RX_DRAIN) { + loop_counter++; + if (loop_counter > MAXITER) + return -1; + } + + /* SIGH. We have to reload the prod_ptr *again* since + * the drain may have caused it to change + */ + prod_ptr = readl(&port->ip_serial_regs->srpir) + & PROD_CONS_MASK; + } + if (reset_dma) { + port->ip_sscr &= ~SSCR_DMA_EN; + writel(port->ip_sscr, &port->ip_serial_regs->sscr); + } + } + inring = port->ip_inring; + port->ip_flags &= ~READ_ABORTED; + + total = 0; + loop_counter = 0xfffff; /* to avoid hangs */ + + /* Grab bytes from the hardware */ + while ((prod_ptr != cons_ptr) && (len > 0)) { + entry = (struct ring_entry *)((caddr_t) inring + cons_ptr); + + if (loop_counter-- <= 0) { + printk(KERN_WARNING "IOC3 serial: " + "possible hang condition/" + "port stuck on read (line %d).\n", + the_port->line); + break; + } + + /* According to the producer pointer, this ring entry + * must contain some data. But if the PIO happened faster + * than the DMA, the data may not be available yet, so let's + * wait until it arrives. + */ + if ((entry->ring_allsc & RING_ANY_VALID) == 0) { + /* Indicate the read is aborted so we don't disable + * the interrupt thinking that the consumer is + * congested. + */ + port->ip_flags |= READ_ABORTED; + len = 0; + break; + } + + /* Load the bytes/status out of the ring entry */ + for (byte_num = 0; byte_num < 4 && len > 0; byte_num++) { + sc = &(entry->ring_sc[byte_num]); + + /* Check for change in modem state or overrun */ + if ((*sc & RXSB_MODEM_VALID) + && (port->ip_notify & N_DDCD)) { + /* Notify upper layer if DCD dropped */ + if ((port->ip_flags & DCD_ON) + && !(*sc & RXSB_DCD)) { + /* If we have already copied some data, + * return it. We'll pick up the carrier + * drop on the next pass. That way we + * don't throw away the data that has + * already been copied back to + * the caller's buffer. + */ + if (total > 0) { + len = 0; + break; + } + port->ip_flags &= ~DCD_ON; + + /* Turn off this notification so the + * carrier drop protocol won't see it + * again when it does a read. + */ + *sc &= ~RXSB_MODEM_VALID; + + /* To keep things consistent, we need + * to update the consumer pointer so + * the next reader won't come in and + * try to read the same ring entries + * again. This must be done here before + * the dcd change. + */ + + if ((entry->ring_allsc & RING_ANY_VALID) + == 0) { + cons_ptr += (int)sizeof + (struct ring_entry); + cons_ptr &= PROD_CONS_MASK; + } + writel(cons_ptr, + &port->ip_serial_regs->srcir); + port->ip_rx_cons = cons_ptr; + + /* Notify upper layer of carrier drop */ + if ((port->ip_notify & N_DDCD) + && port->ip_port) { + uart_handle_dcd_change + (port->ip_port, 0); + wake_up_interruptible + (&the_port->state-> + port.delta_msr_wait); + } + + /* If we had any data to return, we + * would have returned it above. + */ + return 0; + } + } + if (*sc & RXSB_MODEM_VALID) { + /* Notify that an input overrun occurred */ + if ((*sc & RXSB_OVERRUN) + && (port->ip_notify & N_OVERRUN_ERROR)) { + ioc3_cb_post_ncs(the_port, NCS_OVERRUN); + } + /* Don't look at this byte again */ + *sc &= ~RXSB_MODEM_VALID; + } + + /* Check for valid data or RX errors */ + if ((*sc & RXSB_DATA_VALID) && + ((*sc & (RXSB_PAR_ERR + | RXSB_FRAME_ERR | RXSB_BREAK)) + && (port->ip_notify & (N_PARITY_ERROR + | N_FRAMING_ERROR + | N_BREAK)))) { + /* There is an error condition on the next byte. + * If we have already transferred some bytes, + * we'll stop here. Otherwise if this is the + * first byte to be read, we'll just transfer + * it alone after notifying the + * upper layer of its status. + */ + if (total > 0) { + len = 0; + break; + } else { + if ((*sc & RXSB_PAR_ERR) && + (port-> + ip_notify & N_PARITY_ERROR)) { + ioc3_cb_post_ncs(the_port, + NCS_PARITY); + } + if ((*sc & RXSB_FRAME_ERR) && + (port-> + ip_notify & N_FRAMING_ERROR)) { + ioc3_cb_post_ncs(the_port, + NCS_FRAMING); + } + if ((*sc & RXSB_BREAK) + && (port->ip_notify & N_BREAK)) { + ioc3_cb_post_ncs + (the_port, NCS_BREAK); + } + len = 1; + } + } + if (*sc & RXSB_DATA_VALID) { + *sc &= ~RXSB_DATA_VALID; + *buf = entry->ring_data[byte_num]; + buf++; + len--; + total++; + } + } + + /* If we used up this entry entirely, go on to the next one, + * otherwise we must have run out of buffer space, so + * leave the consumer pointer here for the next read in case + * there are still unread bytes in this entry. + */ + if ((entry->ring_allsc & RING_ANY_VALID) == 0) { + cons_ptr += (int)sizeof(struct ring_entry); + cons_ptr &= PROD_CONS_MASK; + } + } + + /* Update consumer pointer and re-arm rx timer interrupt */ + writel(cons_ptr, &port->ip_serial_regs->srcir); + port->ip_rx_cons = cons_ptr; + + /* If we have now dipped below the rx high water mark and we have + * rx_high interrupt turned off, we can now turn it back on again. + */ + if ((port->ip_flags & INPUT_HIGH) && (((prod_ptr - cons_ptr) + & PROD_CONS_MASK) < + ((port-> + ip_sscr & + SSCR_RX_THRESHOLD) + << PROD_CONS_PTR_OFF))) { + port->ip_flags &= ~INPUT_HIGH; + enable_intrs(port, hooks->intr_rx_high); + } + return total; +} + +/** + * receive_chars - upper level read. + * @the_port: port to read from + */ +static int receive_chars(struct uart_port *the_port) +{ + struct tty_struct *tty; + unsigned char ch[MAX_CHARS]; + int read_count = 0, read_room, flip = 0; + struct uart_state *state = the_port->state; + struct ioc3_port *port = get_ioc3_port(the_port); + unsigned long pflags; + + /* Make sure all the pointers are "good" ones */ + if (!state) + return 0; + if (!state->port.tty) + return 0; + + if (!(port->ip_flags & INPUT_ENABLE)) + return 0; + + spin_lock_irqsave(&the_port->lock, pflags); + tty = state->port.tty; + + read_count = do_read(the_port, ch, MAX_CHARS); + if (read_count > 0) { + flip = 1; + read_room = tty_insert_flip_string(tty, ch, read_count); + the_port->icount.rx += read_count; + } + spin_unlock_irqrestore(&the_port->lock, pflags); + + if (flip) + tty_flip_buffer_push(tty); + + return read_count; +} + +/** + * ioc3uart_intr_one - lowest level (per port) interrupt handler. + * @is : submodule + * @idd: driver data + * @pending: interrupts to handle + */ + +static int inline +ioc3uart_intr_one(struct ioc3_submodule *is, + struct ioc3_driver_data *idd, + unsigned int pending) +{ + int port_num = GET_PORT_FROM_SIO_IR(pending); + struct port_hooks *hooks; + unsigned int rx_high_rd_aborted = 0; + unsigned long flags; + struct uart_port *the_port; + struct ioc3_port *port; + int loop_counter; + struct ioc3_card *card_ptr; + unsigned int sio_ir; + + card_ptr = idd->data[is->id]; + port = card_ptr->ic_port[port_num].icp_port; + hooks = port->ip_hooks; + + /* Possible race condition here: The tx_mt interrupt bit may be + * cleared without the intervention of the interrupt handler, + * e.g. by a write. If the top level interrupt handler reads a + * tx_mt, then some other processor does a write, starting up + * output, then we come in here, see the tx_mt and stop DMA, the + * output started by the other processor will hang. Thus we can + * only rely on tx_mt being legitimate if it is read while the + * port lock is held. Therefore this bit must be ignored in the + * passed in interrupt mask which was read by the top level + * interrupt handler since the port lock was not held at the time + * it was read. We can only rely on this bit being accurate if it + * is read while the port lock is held. So we'll clear it for now, + * and reload it later once we have the port lock. + */ + + sio_ir = pending & ~(hooks->intr_tx_mt); + spin_lock_irqsave(&port->ip_lock, flags); + + loop_counter = MAXITER; /* to avoid hangs */ + + do { + uint32_t shadow; + + if (loop_counter-- <= 0) { + printk(KERN_WARNING "IOC3 serial: " + "possible hang condition/" + "port stuck on interrupt (line %d).\n", + ((struct uart_port *)port->ip_port)->line); + break; + } + /* Handle a DCD change */ + if (sio_ir & hooks->intr_delta_dcd) { + ioc3_ack(is, idd, hooks->intr_delta_dcd); + shadow = readl(&port->ip_serial_regs->shadow); + + if ((port->ip_notify & N_DDCD) + && (shadow & SHADOW_DCD) + && (port->ip_port)) { + the_port = port->ip_port; + uart_handle_dcd_change(the_port, + shadow & SHADOW_DCD); + wake_up_interruptible + (&the_port->state->port.delta_msr_wait); + } else if ((port->ip_notify & N_DDCD) + && !(shadow & SHADOW_DCD)) { + /* Flag delta DCD/no DCD */ + uart_handle_dcd_change(port->ip_port, + shadow & SHADOW_DCD); + port->ip_flags |= DCD_ON; + } + } + + /* Handle a CTS change */ + if (sio_ir & hooks->intr_delta_cts) { + ioc3_ack(is, idd, hooks->intr_delta_cts); + shadow = readl(&port->ip_serial_regs->shadow); + + if ((port->ip_notify & N_DCTS) && (port->ip_port)) { + the_port = port->ip_port; + uart_handle_cts_change(the_port, shadow + & SHADOW_CTS); + wake_up_interruptible + (&the_port->state->port.delta_msr_wait); + } + } + + /* rx timeout interrupt. Must be some data available. Put this + * before the check for rx_high since servicing this condition + * may cause that condition to clear. + */ + if (sio_ir & hooks->intr_rx_timer) { + ioc3_ack(is, idd, hooks->intr_rx_timer); + if ((port->ip_notify & N_DATA_READY) + && (port->ip_port)) { + receive_chars(port->ip_port); + } + } + + /* rx high interrupt. Must be after rx_timer. */ + else if (sio_ir & hooks->intr_rx_high) { + /* Data available, notify upper layer */ + if ((port->ip_notify & N_DATA_READY) && port->ip_port) { + receive_chars(port->ip_port); + } + + /* We can't ACK this interrupt. If receive_chars didn't + * cause the condition to clear, we'll have to disable + * the interrupt until the data is drained. + * If the read was aborted, don't disable the interrupt + * as this may cause us to hang indefinitely. An + * aborted read generally means that this interrupt + * hasn't been delivered to the cpu yet anyway, even + * though we see it as asserted when we read the sio_ir. + */ + if ((sio_ir = PENDING(card_ptr, idd)) + & hooks->intr_rx_high) { + if (port->ip_flags & READ_ABORTED) { + rx_high_rd_aborted++; + } + else { + card_ptr->ic_enable &= ~hooks->intr_rx_high; + port->ip_flags |= INPUT_HIGH; + } + } + } + + /* We got a low water interrupt: notify upper layer to + * send more data. Must come before tx_mt since servicing + * this condition may cause that condition to clear. + */ + if (sio_ir & hooks->intr_tx_explicit) { + port->ip_flags &= ~LOWAT_WRITTEN; + ioc3_ack(is, idd, hooks->intr_tx_explicit); + if (port->ip_notify & N_OUTPUT_LOWAT) + ioc3_cb_output_lowat(port); + } + + /* Handle tx_mt. Must come after tx_explicit. */ + else if (sio_ir & hooks->intr_tx_mt) { + /* If we are expecting a lowat notification + * and we get to this point it probably means that for + * some reason the tx_explicit didn't work as expected + * (that can legitimately happen if the output buffer is + * filled up in just the right way). + * So send the notification now. + */ + if (port->ip_notify & N_OUTPUT_LOWAT) { + ioc3_cb_output_lowat(port); + + /* We need to reload the sio_ir since the lowat + * call may have caused another write to occur, + * clearing the tx_mt condition. + */ + sio_ir = PENDING(card_ptr, idd); + } + + /* If the tx_mt condition still persists even after the + * lowat call, we've got some work to do. + */ + if (sio_ir & hooks->intr_tx_mt) { + /* If we are not currently expecting DMA input, + * and the transmitter has just gone idle, + * there is no longer any reason for DMA, so + * disable it. + */ + if (!(port->ip_notify + & (N_DATA_READY | N_DDCD))) { + BUG_ON(!(port->ip_sscr + & SSCR_DMA_EN)); + port->ip_sscr &= ~SSCR_DMA_EN; + writel(port->ip_sscr, + &port->ip_serial_regs->sscr); + } + /* Prevent infinite tx_mt interrupt */ + card_ptr->ic_enable &= ~hooks->intr_tx_mt; + } + } + sio_ir = PENDING(card_ptr, idd); + + /* if the read was aborted and only hooks->intr_rx_high, + * clear hooks->intr_rx_high, so we do not loop forever. + */ + + if (rx_high_rd_aborted && (sio_ir == hooks->intr_rx_high)) { + sio_ir &= ~hooks->intr_rx_high; + } + } while (sio_ir & hooks->intr_all); + + spin_unlock_irqrestore(&port->ip_lock, flags); + ioc3_enable(is, idd, card_ptr->ic_enable); + return 0; +} + +/** + * ioc3uart_intr - field all serial interrupts + * @is : submodule + * @idd: driver data + * @pending: interrupts to handle + * + */ + +static int ioc3uart_intr(struct ioc3_submodule *is, + struct ioc3_driver_data *idd, + unsigned int pending) +{ + int ret = 0; + + /* + * The upper level interrupt handler sends interrupts for both ports + * here. So we need to call for each port with its interrupts. + */ + + if (pending & SIO_IR_SA) + ret |= ioc3uart_intr_one(is, idd, pending & SIO_IR_SA); + if (pending & SIO_IR_SB) + ret |= ioc3uart_intr_one(is, idd, pending & SIO_IR_SB); + + return ret; +} + +/** + * ic3_type + * @port: Port to operate with (we ignore since we only have one port) + * + */ +static const char *ic3_type(struct uart_port *the_port) +{ + if (IS_RS232(the_port->line)) + return "SGI IOC3 Serial [rs232]"; + else + return "SGI IOC3 Serial [rs422]"; +} + +/** + * ic3_tx_empty - Is the transmitter empty? + * @port: Port to operate on + * + */ +static unsigned int ic3_tx_empty(struct uart_port *the_port) +{ + unsigned int ret = 0; + struct ioc3_port *port = get_ioc3_port(the_port); + + if (readl(&port->ip_serial_regs->shadow) & SHADOW_TEMT) + ret = TIOCSER_TEMT; + return ret; +} + +/** + * ic3_stop_tx - stop the transmitter + * @port: Port to operate on + * + */ +static void ic3_stop_tx(struct uart_port *the_port) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + + if (port) + set_notification(port, N_OUTPUT_LOWAT, 0); +} + +/** + * ic3_stop_rx - stop the receiver + * @port: Port to operate on + * + */ +static void ic3_stop_rx(struct uart_port *the_port) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + + if (port) + port->ip_flags &= ~INPUT_ENABLE; +} + +/** + * null_void_function + * @port: Port to operate on + * + */ +static void null_void_function(struct uart_port *the_port) +{ +} + +/** + * ic3_shutdown - shut down the port - free irq and disable + * @port: port to shut down + * + */ +static void ic3_shutdown(struct uart_port *the_port) +{ + unsigned long port_flags; + struct ioc3_port *port; + struct uart_state *state; + + port = get_ioc3_port(the_port); + if (!port) + return; + + state = the_port->state; + wake_up_interruptible(&state->port.delta_msr_wait); + + spin_lock_irqsave(&the_port->lock, port_flags); + set_notification(port, N_ALL, 0); + spin_unlock_irqrestore(&the_port->lock, port_flags); +} + +/** + * ic3_set_mctrl - set control lines (dtr, rts, etc) + * @port: Port to operate on + * @mctrl: Lines to set/unset + * + */ +static void ic3_set_mctrl(struct uart_port *the_port, unsigned int mctrl) +{ + unsigned char mcr = 0; + + if (mctrl & TIOCM_RTS) + mcr |= UART_MCR_RTS; + if (mctrl & TIOCM_DTR) + mcr |= UART_MCR_DTR; + if (mctrl & TIOCM_OUT1) + mcr |= UART_MCR_OUT1; + if (mctrl & TIOCM_OUT2) + mcr |= UART_MCR_OUT2; + if (mctrl & TIOCM_LOOP) + mcr |= UART_MCR_LOOP; + + set_mcr(the_port, mcr, SHADOW_DTR); +} + +/** + * ic3_get_mctrl - get control line info + * @port: port to operate on + * + */ +static unsigned int ic3_get_mctrl(struct uart_port *the_port) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + uint32_t shadow; + unsigned int ret = 0; + + if (!port) + return 0; + + shadow = readl(&port->ip_serial_regs->shadow); + if (shadow & SHADOW_DCD) + ret |= TIOCM_CD; + if (shadow & SHADOW_DR) + ret |= TIOCM_DSR; + if (shadow & SHADOW_CTS) + ret |= TIOCM_CTS; + return ret; +} + +/** + * ic3_start_tx - Start transmitter. Called with the_port->lock + * @port: Port to operate on + * + */ +static void ic3_start_tx(struct uart_port *the_port) +{ + struct ioc3_port *port = get_ioc3_port(the_port); + + if (port) { + set_notification(port, N_OUTPUT_LOWAT, 1); + enable_intrs(port, port->ip_hooks->intr_tx_mt); + } +} + +/** + * ic3_break_ctl - handle breaks + * @port: Port to operate on + * @break_state: Break state + * + */ +static void ic3_break_ctl(struct uart_port *the_port, int break_state) +{ +} + +/** + * ic3_startup - Start up the serial port - always return 0 (We're always on) + * @port: Port to operate on + * + */ +static int ic3_startup(struct uart_port *the_port) +{ + int retval; + struct ioc3_port *port; + struct ioc3_card *card_ptr; + unsigned long port_flags; + + if (!the_port) { + NOT_PROGRESS(); + return -ENODEV; + } + port = get_ioc3_port(the_port); + if (!port) { + NOT_PROGRESS(); + return -ENODEV; + } + card_ptr = port->ip_card; + port->ip_port = the_port; + + if (!card_ptr) { + NOT_PROGRESS(); + return -ENODEV; + } + + /* Start up the serial port */ + spin_lock_irqsave(&the_port->lock, port_flags); + retval = ic3_startup_local(the_port); + spin_unlock_irqrestore(&the_port->lock, port_flags); + return retval; +} + +/** + * ic3_set_termios - set termios stuff + * @port: port to operate on + * @termios: New settings + * @termios: Old + * + */ +static void +ic3_set_termios(struct uart_port *the_port, + struct ktermios *termios, struct ktermios *old_termios) +{ + unsigned long port_flags; + + spin_lock_irqsave(&the_port->lock, port_flags); + ioc3_change_speed(the_port, termios, old_termios); + spin_unlock_irqrestore(&the_port->lock, port_flags); +} + +/** + * ic3_request_port - allocate resources for port - no op.... + * @port: port to operate on + * + */ +static int ic3_request_port(struct uart_port *port) +{ + return 0; +} + +/* Associate the uart functions above - given to serial core */ +static struct uart_ops ioc3_ops = { + .tx_empty = ic3_tx_empty, + .set_mctrl = ic3_set_mctrl, + .get_mctrl = ic3_get_mctrl, + .stop_tx = ic3_stop_tx, + .start_tx = ic3_start_tx, + .stop_rx = ic3_stop_rx, + .enable_ms = null_void_function, + .break_ctl = ic3_break_ctl, + .startup = ic3_startup, + .shutdown = ic3_shutdown, + .set_termios = ic3_set_termios, + .type = ic3_type, + .release_port = null_void_function, + .request_port = ic3_request_port, +}; + +/* + * Boot-time initialization code + */ + +static struct uart_driver ioc3_uart = { + .owner = THIS_MODULE, + .driver_name = "ioc3_serial", + .dev_name = DEVICE_NAME, + .major = DEVICE_MAJOR, + .minor = DEVICE_MINOR, + .nr = MAX_LOGICAL_PORTS +}; + +/** + * ioc3_serial_core_attach - register with serial core + * This is done during pci probing + * @is: submodule struct for this + * @idd: handle for this card + */ +static inline int ioc3_serial_core_attach( struct ioc3_submodule *is, + struct ioc3_driver_data *idd) +{ + struct ioc3_port *port; + struct uart_port *the_port; + struct ioc3_card *card_ptr = idd->data[is->id]; + int ii, phys_port; + struct pci_dev *pdev = idd->pdev; + + DPRINT_CONFIG(("%s: attach pdev 0x%p - card_ptr 0x%p\n", + __func__, pdev, (void *)card_ptr)); + + if (!card_ptr) + return -ENODEV; + + /* once around for each logical port on this card */ + for (ii = 0; ii < LOGICAL_PORTS_PER_CARD; ii++) { + phys_port = GET_PHYSICAL_PORT(ii); + the_port = &card_ptr->ic_port[phys_port]. + icp_uart_port[GET_LOGICAL_PORT(ii)]; + port = card_ptr->ic_port[phys_port].icp_port; + port->ip_port = the_port; + + DPRINT_CONFIG(("%s: attach the_port 0x%p / port 0x%p [%d/%d]\n", + __func__, (void *)the_port, (void *)port, + phys_port, ii)); + + /* membase, iobase and mapbase just need to be non-0 */ + the_port->membase = (unsigned char __iomem *)1; + the_port->iobase = (pdev->bus->number << 16) | ii; + the_port->line = (Num_of_ioc3_cards << 2) | ii; + the_port->mapbase = 1; + the_port->type = PORT_16550A; + the_port->fifosize = FIFO_SIZE; + the_port->ops = &ioc3_ops; + the_port->irq = idd->irq_io; + the_port->dev = &pdev->dev; + + if (uart_add_one_port(&ioc3_uart, the_port) < 0) { + printk(KERN_WARNING + "%s: unable to add port %d bus %d\n", + __func__, the_port->line, pdev->bus->number); + } else { + DPRINT_CONFIG(("IOC3 serial port %d irq %d bus %d\n", + the_port->line, the_port->irq, pdev->bus->number)); + } + + /* all ports are rs232 for now */ + if (IS_PHYSICAL_PORT(ii)) + ioc3_set_proto(port, PROTO_RS232); + } + return 0; +} + +/** + * ioc3uart_remove - register detach function + * @is: submodule struct for this submodule + * @idd: ioc3 driver data for this submodule + */ + +static int ioc3uart_remove(struct ioc3_submodule *is, + struct ioc3_driver_data *idd) +{ + struct ioc3_card *card_ptr = idd->data[is->id]; + struct uart_port *the_port; + struct ioc3_port *port; + int ii; + + if (card_ptr) { + for (ii = 0; ii < LOGICAL_PORTS_PER_CARD; ii++) { + the_port = &card_ptr->ic_port[GET_PHYSICAL_PORT(ii)]. + icp_uart_port[GET_LOGICAL_PORT(ii)]; + if (the_port) + uart_remove_one_port(&ioc3_uart, the_port); + port = card_ptr->ic_port[GET_PHYSICAL_PORT(ii)].icp_port; + if (port && IS_PHYSICAL_PORT(ii) + && (GET_PHYSICAL_PORT(ii) == 0)) { + pci_free_consistent(port->ip_idd->pdev, + TOTAL_RING_BUF_SIZE, + (void *)port->ip_cpu_ringbuf, + port->ip_dma_ringbuf); + kfree(port); + card_ptr->ic_port[GET_PHYSICAL_PORT(ii)]. + icp_port = NULL; + } + } + kfree(card_ptr); + idd->data[is->id] = NULL; + } + return 0; +} + +/** + * ioc3uart_probe - card probe function called from shim driver + * @is: submodule struct for this submodule + * @idd: ioc3 driver data for this card + */ + +static int __devinit +ioc3uart_probe(struct ioc3_submodule *is, struct ioc3_driver_data *idd) +{ + struct pci_dev *pdev = idd->pdev; + struct ioc3_card *card_ptr; + int ret = 0; + struct ioc3_port *port; + struct ioc3_port *ports[PORTS_PER_CARD]; + int phys_port; + int cnt; + + DPRINT_CONFIG(("%s (0x%p, 0x%p)\n", __func__, is, idd)); + + card_ptr = kzalloc(sizeof(struct ioc3_card), GFP_KERNEL); + if (!card_ptr) { + printk(KERN_WARNING "ioc3_attach_one" + ": unable to get memory for the IOC3\n"); + return -ENOMEM; + } + idd->data[is->id] = card_ptr; + Submodule_slot = is->id; + + writel(((UARTA_BASE >> 3) << SIO_CR_SER_A_BASE_SHIFT) | + ((UARTB_BASE >> 3) << SIO_CR_SER_B_BASE_SHIFT) | + (0xf << SIO_CR_CMD_PULSE_SHIFT), &idd->vma->sio_cr); + + pci_write_config_dword(pdev, PCI_LAT, 0xff00); + + /* Enable serial port mode select generic PIO pins as outputs */ + ioc3_gpcr_set(idd, GPCR_UARTA_MODESEL | GPCR_UARTB_MODESEL); + + /* Create port structures for each port */ + for (phys_port = 0; phys_port < PORTS_PER_CARD; phys_port++) { + port = kzalloc(sizeof(struct ioc3_port), GFP_KERNEL); + if (!port) { + printk(KERN_WARNING + "IOC3 serial memory not available for port\n"); + ret = -ENOMEM; + goto out4; + } + spin_lock_init(&port->ip_lock); + + /* we need to remember the previous ones, to point back to + * them farther down - setting up the ring buffers. + */ + ports[phys_port] = port; + + /* init to something useful */ + card_ptr->ic_port[phys_port].icp_port = port; + port->ip_is = is; + port->ip_idd = idd; + port->ip_baud = 9600; + port->ip_card = card_ptr; + port->ip_hooks = &hooks_array[phys_port]; + + /* Setup each port */ + if (phys_port == 0) { + port->ip_serial_regs = &idd->vma->port_a; + port->ip_uart_regs = &idd->vma->sregs.uarta; + + DPRINT_CONFIG(("%s : Port A ip_serial_regs 0x%p " + "ip_uart_regs 0x%p\n", + __func__, + (void *)port->ip_serial_regs, + (void *)port->ip_uart_regs)); + + /* setup ring buffers */ + port->ip_cpu_ringbuf = pci_alloc_consistent(pdev, + TOTAL_RING_BUF_SIZE, &port->ip_dma_ringbuf); + + BUG_ON(!((((int64_t) port->ip_dma_ringbuf) & + (TOTAL_RING_BUF_SIZE - 1)) == 0)); + port->ip_inring = RING(port, RX_A); + port->ip_outring = RING(port, TX_A); + DPRINT_CONFIG(("%s : Port A ip_cpu_ringbuf 0x%p " + "ip_dma_ringbuf 0x%p, ip_inring 0x%p " + "ip_outring 0x%p\n", + __func__, + (void *)port->ip_cpu_ringbuf, + (void *)port->ip_dma_ringbuf, + (void *)port->ip_inring, + (void *)port->ip_outring)); + } + else { + port->ip_serial_regs = &idd->vma->port_b; + port->ip_uart_regs = &idd->vma->sregs.uartb; + + DPRINT_CONFIG(("%s : Port B ip_serial_regs 0x%p " + "ip_uart_regs 0x%p\n", + __func__, + (void *)port->ip_serial_regs, + (void *)port->ip_uart_regs)); + + /* share the ring buffers */ + port->ip_dma_ringbuf = + ports[phys_port - 1]->ip_dma_ringbuf; + port->ip_cpu_ringbuf = + ports[phys_port - 1]->ip_cpu_ringbuf; + port->ip_inring = RING(port, RX_B); + port->ip_outring = RING(port, TX_B); + DPRINT_CONFIG(("%s : Port B ip_cpu_ringbuf 0x%p " + "ip_dma_ringbuf 0x%p, ip_inring 0x%p " + "ip_outring 0x%p\n", + __func__, + (void *)port->ip_cpu_ringbuf, + (void *)port->ip_dma_ringbuf, + (void *)port->ip_inring, + (void *)port->ip_outring)); + } + + DPRINT_CONFIG(("%s : port %d [addr 0x%p] card_ptr 0x%p", + __func__, + phys_port, (void *)port, (void *)card_ptr)); + DPRINT_CONFIG((" ip_serial_regs 0x%p ip_uart_regs 0x%p\n", + (void *)port->ip_serial_regs, + (void *)port->ip_uart_regs)); + + /* Initialize the hardware for IOC3 */ + port_init(port); + + DPRINT_CONFIG(("%s: phys_port %d port 0x%p inring 0x%p " + "outring 0x%p\n", + __func__, + phys_port, (void *)port, + (void *)port->ip_inring, + (void *)port->ip_outring)); + + } + + /* register port with the serial core */ + + if ((ret = ioc3_serial_core_attach(is, idd))) + goto out4; + + Num_of_ioc3_cards++; + + return ret; + + /* error exits that give back resources */ +out4: + for (cnt = 0; cnt < phys_port; cnt++) + kfree(ports[cnt]); + + kfree(card_ptr); + return ret; +} + +static struct ioc3_submodule ioc3uart_ops = { + .name = "IOC3uart", + .probe = ioc3uart_probe, + .remove = ioc3uart_remove, + /* call .intr for both ports initially */ + .irq_mask = SIO_IR_SA | SIO_IR_SB, + .intr = ioc3uart_intr, + .owner = THIS_MODULE, +}; + +/** + * ioc3_detect - module init called, + */ +static int __init ioc3uart_init(void) +{ + int ret; + + /* register with serial core */ + if ((ret = uart_register_driver(&ioc3_uart)) < 0) { + printk(KERN_WARNING + "%s: Couldn't register IOC3 uart serial driver\n", + __func__); + return ret; + } + ret = ioc3_register_submodule(&ioc3uart_ops); + if (ret) + uart_unregister_driver(&ioc3_uart); + return ret; +} + +static void __exit ioc3uart_exit(void) +{ + ioc3_unregister_submodule(&ioc3uart_ops); + uart_unregister_driver(&ioc3_uart); +} + +module_init(ioc3uart_init); +module_exit(ioc3uart_exit); + +MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>"); +MODULE_DESCRIPTION("Serial PCI driver module for SGI IOC3 card"); +MODULE_LICENSE("GPL"); |