Nano_Allwinner
/
ubuntu-linux-kernel
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases 1 Wiki Activity
ubuntu-linux-kernel/drivers/tty/serial/ioc3_serial.c

2196 lines
57 KiB
C
Raw Permalink Normal View History

2
2024-04-01 15:06:58 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* 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/tty_flip.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 inline int 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.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;
int byte_num;
char *sc;
int loop_counter;
BUG_ON(!(len >= 0));
BUG_ON(!port);
hooks = port->ip_hooks;
/* 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)
{
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 (!(port->ip_flags & INPUT_ENABLE))
return 0;
spin_lock_irqsave(&the_port->lock, pflags);
read_count = do_read(the_port, ch, MAX_CHARS);
if (read_count > 0) {
flip = 1;
read_room = tty_insert_flip_string(&state->port, ch,
read_count);
the_port->icount.rx += read_count;
}
spin_unlock_irqrestore(&the_port->lock, pflags);
if (flip)
tty_flip_buffer_push(&state->port);
return read_count;
}
/**
* ioc3uart_intr_one - lowest level (per port) interrupt handler.
* @is : submodule
* @idd: driver data
* @pending: interrupts to handle
*/
static inline int
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 const 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,
.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
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 */
ret = ioc3_serial_core_attach(is, idd);
if (ret)
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");