blob: ad40c75bb58f84d5aceba4ca5340f673b16e0a75 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for CPM (SCC/SMC) serial ports; core driver
*
* Based on arch/ppc/cpm2_io/uart.c by Dan Malek
* Based on ppc8xx.c by Thomas Gleixner
* Based on drivers/serial/amba.c by Russell King
*
* Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
* Pantelis Antoniou (panto@intracom.gr) (CPM1)
*
* Copyright (C) 2004, 2007 Freescale Semiconductor, Inc.
* (C) 2004 Intracom, S.A.
* (C) 2005-2006 MontaVista Software, Inc.
* Vitaly Bordug <vbordug@ru.mvista.com>
*/
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/device.h>
#include <linux/bootmem.h>
#include <linux/dma-mapping.h>
#include <linux/fs_uart_pd.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/delay.h>
#include <asm/fs_pd.h>
#include <asm/udbg.h>
#if defined(CONFIG_SERIAL_CPM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/serial_core.h>
#include <linux/kernel.h>
#include "cpm_uart.h"
/**************************************************************/
static int cpm_uart_tx_pump(struct uart_port *port);
static void cpm_uart_init_smc(struct uart_cpm_port *pinfo);
static void cpm_uart_init_scc(struct uart_cpm_port *pinfo);
static void cpm_uart_initbd(struct uart_cpm_port *pinfo);
/**************************************************************/
#define HW_BUF_SPD_THRESHOLD 2400
/*
* Check, if transmit buffers are processed
*/
static unsigned int cpm_uart_tx_empty(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
cbd_t __iomem *bdp = pinfo->tx_bd_base;
int ret = 0;
while (1) {
if (in_be16(&bdp->cbd_sc) & BD_SC_READY)
break;
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) {
ret = TIOCSER_TEMT;
break;
}
bdp++;
}
pr_debug("CPM uart[%d]:tx_empty: %d\n", port->line, ret);
return ret;
}
static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
if (pinfo->gpios[GPIO_RTS] >= 0)
gpio_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS));
if (pinfo->gpios[GPIO_DTR] >= 0)
gpio_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR));
}
static unsigned int cpm_uart_get_mctrl(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
if (pinfo->gpios[GPIO_CTS] >= 0) {
if (gpio_get_value(pinfo->gpios[GPIO_CTS]))
mctrl &= ~TIOCM_CTS;
}
if (pinfo->gpios[GPIO_DSR] >= 0) {
if (gpio_get_value(pinfo->gpios[GPIO_DSR]))
mctrl &= ~TIOCM_DSR;
}
if (pinfo->gpios[GPIO_DCD] >= 0) {
if (gpio_get_value(pinfo->gpios[GPIO_DCD]))
mctrl &= ~TIOCM_CAR;
}
if (pinfo->gpios[GPIO_RI] >= 0) {
if (!gpio_get_value(pinfo->gpios[GPIO_RI]))
mctrl |= TIOCM_RNG;
}
return mctrl;
}
/*
* Stop transmitter
*/
static void cpm_uart_stop_tx(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
smc_t __iomem *smcp = pinfo->smcp;
scc_t __iomem *sccp = pinfo->sccp;
pr_debug("CPM uart[%d]:stop tx\n", port->line);
if (IS_SMC(pinfo))
clrbits8(&smcp->smc_smcm, SMCM_TX);
else
clrbits16(&sccp->scc_sccm, UART_SCCM_TX);
}
/*
* Start transmitter
*/
static void cpm_uart_start_tx(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
smc_t __iomem *smcp = pinfo->smcp;
scc_t __iomem *sccp = pinfo->sccp;
pr_debug("CPM uart[%d]:start tx\n", port->line);
if (IS_SMC(pinfo)) {
if (in_8(&smcp->smc_smcm) & SMCM_TX)
return;
} else {
if (in_be16(&sccp->scc_sccm) & UART_SCCM_TX)
return;
}
if (cpm_uart_tx_pump(port) != 0) {
if (IS_SMC(pinfo)) {
setbits8(&smcp->smc_smcm, SMCM_TX);
} else {
setbits16(&sccp->scc_sccm, UART_SCCM_TX);
}
}
}
/*
* Stop receiver
*/
static void cpm_uart_stop_rx(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
smc_t __iomem *smcp = pinfo->smcp;
scc_t __iomem *sccp = pinfo->sccp;
pr_debug("CPM uart[%d]:stop rx\n", port->line);
if (IS_SMC(pinfo))
clrbits8(&smcp->smc_smcm, SMCM_RX);
else
clrbits16(&sccp->scc_sccm, UART_SCCM_RX);
}
/*
* Generate a break.
*/
static void cpm_uart_break_ctl(struct uart_port *port, int break_state)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
pr_debug("CPM uart[%d]:break ctrl, break_state: %d\n", port->line,
break_state);
if (break_state)
cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
else
cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
}
/*
* Transmit characters, refill buffer descriptor, if possible
*/
static void cpm_uart_int_tx(struct uart_port *port)
{
pr_debug("CPM uart[%d]:TX INT\n", port->line);
cpm_uart_tx_pump(port);
}
#ifdef CONFIG_CONSOLE_POLL
static int serial_polled;
#endif
/*
* Receive characters
*/
static void cpm_uart_int_rx(struct uart_port *port)
{
int i;
unsigned char ch;
u8 *cp;
struct tty_port *tport = &port->state->port;
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
cbd_t __iomem *bdp;
u16 status;
unsigned int flg;
pr_debug("CPM uart[%d]:RX INT\n", port->line);
/* Just loop through the closed BDs and copy the characters into
* the buffer.
*/
bdp = pinfo->rx_cur;
for (;;) {
#ifdef CONFIG_CONSOLE_POLL
if (unlikely(serial_polled)) {
serial_polled = 0;
return;
}
#endif
/* get status */
status = in_be16(&bdp->cbd_sc);
/* If this one is empty, return happy */
if (status & BD_SC_EMPTY)
break;
/* get number of characters, and check spce in flip-buffer */
i = in_be16(&bdp->cbd_datlen);
/* If we have not enough room in tty flip buffer, then we try
* later, which will be the next rx-interrupt or a timeout
*/
if (tty_buffer_request_room(tport, i) < i) {
printk(KERN_WARNING "No room in flip buffer\n");
return;
}
/* get pointer */
cp = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
/* loop through the buffer */
while (i-- > 0) {
ch = *cp++;
port->icount.rx++;
flg = TTY_NORMAL;
if (status &
(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
goto handle_error;
if (uart_handle_sysrq_char(port, ch))
continue;
#ifdef CONFIG_CONSOLE_POLL
if (unlikely(serial_polled)) {
serial_polled = 0;
return;
}
#endif
error_return:
tty_insert_flip_char(tport, ch, flg);
} /* End while (i--) */
/* This BD is ready to be used again. Clear status. get next */
clrbits16(&bdp->cbd_sc, BD_SC_BR | BD_SC_FR | BD_SC_PR |
BD_SC_OV | BD_SC_ID);
setbits16(&bdp->cbd_sc, BD_SC_EMPTY);
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
bdp = pinfo->rx_bd_base;
else
bdp++;
} /* End for (;;) */
/* Write back buffer pointer */
pinfo->rx_cur = bdp;
/* activate BH processing */
tty_flip_buffer_push(tport);
return;
/* Error processing */
handle_error:
/* Statistics */
if (status & BD_SC_BR)
port->icount.brk++;
if (status & BD_SC_PR)
port->icount.parity++;
if (status & BD_SC_FR)
port->icount.frame++;
if (status & BD_SC_OV)
port->icount.overrun++;
/* Mask out ignored conditions */
status &= port->read_status_mask;
/* Handle the remaining ones */
if (status & BD_SC_BR)
flg = TTY_BREAK;
else if (status & BD_SC_PR)
flg = TTY_PARITY;
else if (status & BD_SC_FR)
flg = TTY_FRAME;
/* overrun does not affect the current character ! */
if (status & BD_SC_OV) {
ch = 0;
flg = TTY_OVERRUN;
/* We skip this buffer */
/* CHECK: Is really nothing senseful there */
/* ASSUMPTION: it contains nothing valid */
i = 0;
}
#ifdef SUPPORT_SYSRQ
port->sysrq = 0;
#endif
goto error_return;
}
/*
* Asynchron mode interrupt handler
*/
static irqreturn_t cpm_uart_int(int irq, void *data)
{
u8 events;
struct uart_port *port = data;
struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port;
smc_t __iomem *smcp = pinfo->smcp;
scc_t __iomem *sccp = pinfo->sccp;
pr_debug("CPM uart[%d]:IRQ\n", port->line);
if (IS_SMC(pinfo)) {
events = in_8(&smcp->smc_smce);
out_8(&smcp->smc_smce, events);
if (events & SMCM_BRKE)
uart_handle_break(port);
if (events & SMCM_RX)
cpm_uart_int_rx(port);
if (events & SMCM_TX)
cpm_uart_int_tx(port);
} else {
events = in_be16(&sccp->scc_scce);
out_be16(&sccp->scc_scce, events);
if (events & UART_SCCM_BRKE)
uart_handle_break(port);
if (events & UART_SCCM_RX)
cpm_uart_int_rx(port);
if (events & UART_SCCM_TX)
cpm_uart_int_tx(port);
}
return (events) ? IRQ_HANDLED : IRQ_NONE;
}
static int cpm_uart_startup(struct uart_port *port)
{
int retval;
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
pr_debug("CPM uart[%d]:startup\n", port->line);
/* If the port is not the console, make sure rx is disabled. */
if (!(pinfo->flags & FLAG_CONSOLE)) {
/* Disable UART rx */
if (IS_SMC(pinfo)) {
clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN);
clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
} else {
clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR);
clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
}
cpm_uart_initbd(pinfo);
if (IS_SMC(pinfo)) {
out_be32(&pinfo->smcup->smc_rstate, 0);
out_be32(&pinfo->smcup->smc_tstate, 0);
out_be16(&pinfo->smcup->smc_rbptr,
in_be16(&pinfo->smcup->smc_rbase));
out_be16(&pinfo->smcup->smc_tbptr,
in_be16(&pinfo->smcup->smc_tbase));
} else {
cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
}
}
/* Install interrupt handler. */
retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
if (retval)
return retval;
/* Startup rx-int */
if (IS_SMC(pinfo)) {
setbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
setbits16(&pinfo->smcp->smc_smcmr, (SMCMR_REN | SMCMR_TEN));
} else {
setbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT));
}
return 0;
}
inline void cpm_uart_wait_until_send(struct uart_cpm_port *pinfo)
{
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(pinfo->wait_closing);
}
/*
* Shutdown the uart
*/
static void cpm_uart_shutdown(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
pr_debug("CPM uart[%d]:shutdown\n", port->line);
/* free interrupt handler */
free_irq(port->irq, port);
/* If the port is not the console, disable Rx and Tx. */
if (!(pinfo->flags & FLAG_CONSOLE)) {
/* Wait for all the BDs marked sent */
while(!cpm_uart_tx_empty(port)) {
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(2);
}
if (pinfo->wait_closing)
cpm_uart_wait_until_send(pinfo);
/* Stop uarts */
if (IS_SMC(pinfo)) {
smc_t __iomem *smcp = pinfo->smcp;
clrbits16(&smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
clrbits8(&smcp->smc_smcm, SMCM_RX | SMCM_TX);
} else {
scc_t __iomem *sccp = pinfo->sccp;
clrbits32(&sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
clrbits16(&sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
}
/* Shut them really down and reinit buffer descriptors */
if (IS_SMC(pinfo)) {
out_be16(&pinfo->smcup->smc_brkcr, 0);
cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
} else {
out_be16(&pinfo->sccup->scc_brkcr, 0);
cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
}
cpm_uart_initbd(pinfo);
}
}
static void cpm_uart_set_termios(struct uart_port *port,
struct ktermios *termios,
struct ktermios *old)
{
int baud;
unsigned long flags;
u16 cval, scval, prev_mode;
int bits, sbits;
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
smc_t __iomem *smcp = pinfo->smcp;
scc_t __iomem *sccp = pinfo->sccp;
int maxidl;
pr_debug("CPM uart[%d]:set_termios\n", port->line);
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
if (baud < HW_BUF_SPD_THRESHOLD ||
(pinfo->port.state && pinfo->port.state->port.low_latency))
pinfo->rx_fifosize = 1;
else
pinfo->rx_fifosize = RX_BUF_SIZE;
/* MAXIDL is the timeout after which a receive buffer is closed
* when not full if no more characters are received.
* We calculate it from the baudrate so that the duration is
* always the same at standard rates: about 4ms.
*/
maxidl = baud / 2400;
if (maxidl < 1)
maxidl = 1;
if (maxidl > 0x10)
maxidl = 0x10;
/* Character length programmed into the mode register is the
* sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
* 1 or 2 stop bits, minus 1.
* The value 'bits' counts this for us.
*/
cval = 0;
scval = 0;
/* byte size */
switch (termios->c_cflag & CSIZE) {
case CS5:
bits = 5;
break;
case CS6:
bits = 6;
break;
case CS7:
bits = 7;
break;
case CS8:
bits = 8;
break;
/* Never happens, but GCC is too dumb to figure it out */
default:
bits = 8;
break;
}
sbits = bits - 5;
if (termios->c_cflag & CSTOPB) {
cval |= SMCMR_SL; /* Two stops */
scval |= SCU_PSMR_SL;
bits++;
}
if (termios->c_cflag & PARENB) {
cval |= SMCMR_PEN;
scval |= SCU_PSMR_PEN;
bits++;
if (!(termios->c_cflag & PARODD)) {
cval |= SMCMR_PM_EVEN;
scval |= (SCU_PSMR_REVP | SCU_PSMR_TEVP);
}
}
/*
* Update the timeout
*/
uart_update_timeout(port, termios->c_cflag, baud);
/*
* Set up parity check flag
*/
#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
port->read_status_mask = (BD_SC_EMPTY | BD_SC_OV);
if (termios->c_iflag & INPCK)
port->read_status_mask |= BD_SC_FR | BD_SC_PR;
if ((termios->c_iflag & BRKINT) || (termios->c_iflag & PARMRK))
port->read_status_mask |= BD_SC_BR;
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= BD_SC_BR;
/*
* If we're ignore parity and break indicators, ignore
* overruns too. (For real raw support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= BD_SC_OV;
}
/*
* !!! ignore all characters if CREAD is not set
*/
if ((termios->c_cflag & CREAD) == 0)
port->read_status_mask &= ~BD_SC_EMPTY;
spin_lock_irqsave(&port->lock, flags);
/* Start bit has not been added (so don't, because we would just
* subtract it later), and we need to add one for the number of
* stops bits (there is always at least one).
*/
bits++;
if (IS_SMC(pinfo)) {
/*
* MRBLR can be changed while an SMC/SCC is operating only
* if it is done in a single bus cycle with one 16-bit move
* (not two 8-bit bus cycles back-to-back). This occurs when
* the cp shifts control to the next RxBD, so the change does
* not take effect immediately. To guarantee the exact RxBD
* on which the change occurs, change MRBLR only while the
* SMC/SCC receiver is disabled.
*/
out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize);
out_be16(&pinfo->smcup->smc_maxidl, maxidl);
/* Set the mode register. We want to keep a copy of the
* enables, because we want to put them back if they were
* present.
*/
prev_mode = in_be16(&smcp->smc_smcmr) & (SMCMR_REN | SMCMR_TEN);
/* Output in *one* operation, so we don't interrupt RX/TX if they
* were already enabled. */
out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits) | cval |
SMCMR_SM_UART | prev_mode);
} else {
out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
out_be16(&pinfo->sccup->scc_maxidl, maxidl);
out_be16(&sccp->scc_psmr, (sbits << 12) | scval);
}
if (pinfo->clk)
clk_set_rate(pinfo->clk, baud);
else
cpm_set_brg(pinfo->brg - 1, baud);
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *cpm_uart_type(struct uart_port *port)
{
pr_debug("CPM uart[%d]:uart_type\n", port->line);
return port->type == PORT_CPM ? "CPM UART" : NULL;
}
/*
* verify the new serial_struct (for TIOCSSERIAL).
*/
static int cpm_uart_verify_port(struct uart_port *port,
struct serial_struct *ser)
{
int ret = 0;
pr_debug("CPM uart[%d]:verify_port\n", port->line);
if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
ret = -EINVAL;
if (ser->irq < 0 || ser->irq >= nr_irqs)
ret = -EINVAL;
if (ser->baud_base < 9600)
ret = -EINVAL;
return ret;
}
/*
* Transmit characters, refill buffer descriptor, if possible
*/
static int cpm_uart_tx_pump(struct uart_port *port)
{
cbd_t __iomem *bdp;
u8 *p;
int count;
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
struct circ_buf *xmit = &port->state->xmit;
/* Handle xon/xoff */
if (port->x_char) {
/* Pick next descriptor and fill from buffer */
bdp = pinfo->tx_cur;
p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
*p++ = port->x_char;
out_be16(&bdp->cbd_datlen, 1);
setbits16(&bdp->cbd_sc, BD_SC_READY);
/* Get next BD. */
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
bdp = pinfo->tx_bd_base;
else
bdp++;
pinfo->tx_cur = bdp;
port->icount.tx++;
port->x_char = 0;
return 1;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
cpm_uart_stop_tx(port);
return 0;
}
/* Pick next descriptor and fill from buffer */
bdp = pinfo->tx_cur;
while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) &&
xmit->tail != xmit->head) {
count = 0;
p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
while (count < pinfo->tx_fifosize) {
*p++ = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
count++;
if (xmit->head == xmit->tail)
break;
}
out_be16(&bdp->cbd_datlen, count);
setbits16(&bdp->cbd_sc, BD_SC_READY);
/* Get next BD. */
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
bdp = pinfo->tx_bd_base;
else
bdp++;
}
pinfo->tx_cur = bdp;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit)) {
cpm_uart_stop_tx(port);
return 0;
}
return 1;
}
/*
* init buffer descriptors
*/
static void cpm_uart_initbd(struct uart_cpm_port *pinfo)
{
int i;
u8 *mem_addr;
cbd_t __iomem *bdp;
pr_debug("CPM uart[%d]:initbd\n", pinfo->port.line);
/* Set the physical address of the host memory
* buffers in the buffer descriptors, and the
* virtual address for us to work with.
*/
mem_addr = pinfo->mem_addr;
bdp = pinfo->rx_cur = pinfo->rx_bd_base;
for (i = 0; i < (pinfo->rx_nrfifos - 1); i++, bdp++) {
out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
out_be16(&bdp->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
mem_addr += pinfo->rx_fifosize;
}
out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
/* Set the physical address of the host memory
* buffers in the buffer descriptors, and the
* virtual address for us to work with.
*/
mem_addr = pinfo->mem_addr + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize);
bdp = pinfo->tx_cur = pinfo->tx_bd_base;
for (i = 0; i < (pinfo->tx_nrfifos - 1); i++, bdp++) {
out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
out_be16(&bdp->cbd_sc, BD_SC_INTRPT);
mem_addr += pinfo->tx_fifosize;
}
out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_INTRPT);
}
static void cpm_uart_init_scc(struct uart_cpm_port *pinfo)
{
scc_t __iomem *scp;
scc_uart_t __iomem *sup;
pr_debug("CPM uart[%d]:init_scc\n", pinfo->port.line);
scp = pinfo->sccp;
sup = pinfo->sccup;
/* Store address */
out_be16(&pinfo->sccup->scc_genscc.scc_rbase,
(u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
out_be16(&pinfo->sccup->scc_genscc.scc_tbase,
(u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
/* Set up the uart parameters in the
* parameter ram.
*/
cpm_set_scc_fcr(sup);
out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
out_be16(&sup->scc_maxidl, 0x10);
out_be16(&sup->scc_brkcr, 1);
out_be16(&sup->scc_parec, 0);
out_be16(&sup->scc_frmec, 0);
out_be16(&sup->scc_nosec, 0);
out_be16(&sup->scc_brkec, 0);
out_be16(&sup->scc_uaddr1, 0);
out_be16(&sup->scc_uaddr2, 0);
out_be16(&sup->scc_toseq, 0);
out_be16(&sup->scc_char1, 0x8000);
out_be16(&sup->scc_char2, 0x8000);
out_be16(&sup->scc_char3, 0x8000);
out_be16(&sup->scc_char4, 0x8000);
out_be16(&sup->scc_char5, 0x8000);
out_be16(&sup->scc_char6, 0x8000);
out_be16(&sup->scc_char7, 0x8000);
out_be16(&sup->scc_char8, 0x8000);
out_be16(&sup->scc_rccm, 0xc0ff);
/* Send the CPM an initialize command.
*/
cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
/* Set UART mode, 8 bit, no parity, one stop.
* Enable receive and transmit.
*/
out_be32(&scp->scc_gsmrh, 0);
out_be32(&scp->scc_gsmrl,
SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);
/* Enable rx interrupts and clear all pending events. */
out_be16(&scp->scc_sccm, 0);
out_be16(&scp->scc_scce, 0xffff);
out_be16(&scp->scc_dsr, 0x7e7e);
out_be16(&scp->scc_psmr, 0x3000);
setbits32(&scp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
}
static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
{
smc_t __iomem *sp;
smc_uart_t __iomem *up;
pr_debug("CPM uart[%d]:init_smc\n", pinfo->port.line);
sp = pinfo->smcp;
up = pinfo->smcup;
/* Store address */
out_be16(&pinfo->smcup->smc_rbase,
(u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
out_be16(&pinfo->smcup->smc_tbase,
(u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
/*
* In case SMC is being relocated...
*/
out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase));
out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase));
out_be32(&up->smc_rstate, 0);
out_be32(&up->smc_tstate, 0);
out_be16(&up->smc_brkcr, 1); /* number of break chars */
out_be16(&up->smc_brkec, 0);
/* Set up the uart parameters in the
* parameter ram.
*/
cpm_set_smc_fcr(up);
/* Using idle character time requires some additional tuning. */
out_be16(&up->smc_mrblr, pinfo->rx_fifosize);
out_be16(&up->smc_maxidl, 0x10);
out_be16(&up->smc_brklen, 0);
out_be16(&up->smc_brkec, 0);
out_be16(&up->smc_brkcr, 1);
/* Set UART mode, 8 bit, no parity, one stop.
* Enable receive and transmit.
*/
out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART);
/* Enable only rx interrupts clear all pending events. */
out_8(&sp->smc_smcm, 0);
out_8(&sp->smc_smce, 0xff);
setbits16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
}
/*
* Initialize port. This is called from early_console stuff
* so we have to be careful here !
*/
static int cpm_uart_request_port(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
int ret;
pr_debug("CPM uart[%d]:request port\n", port->line);
if (pinfo->flags & FLAG_CONSOLE)
return 0;
if (IS_SMC(pinfo)) {
clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
} else {
clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
}
ret = cpm_uart_allocbuf(pinfo, 0);
if (ret)
return ret;
cpm_uart_initbd(pinfo);
if (IS_SMC(pinfo))
cpm_uart_init_smc(pinfo);
else
cpm_uart_init_scc(pinfo);
return 0;
}
static void cpm_uart_release_port(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
if (!(pinfo->flags & FLAG_CONSOLE))
cpm_uart_freebuf(pinfo);
}
/*
* Configure/autoconfigure the port.
*/
static void cpm_uart_config_port(struct uart_port *port, int flags)
{
pr_debug("CPM uart[%d]:config_port\n", port->line);
if (flags & UART_CONFIG_TYPE) {
port->type = PORT_CPM;
cpm_uart_request_port(port);
}
}
#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_CPM_CONSOLE)
/*
* Write a string to the serial port
* Note that this is called with interrupts already disabled
*/
static void cpm_uart_early_write(struct uart_cpm_port *pinfo,
const char *string, u_int count, bool handle_linefeed)
{
unsigned int i;
cbd_t __iomem *bdp, *bdbase;
unsigned char *cpm_outp_addr;
/* Get the address of the host memory buffer.
*/
bdp = pinfo->tx_cur;
bdbase = pinfo->tx_bd_base;
/*
* Now, do each character. This is not as bad as it looks
* since this is a holding FIFO and not a transmitting FIFO.
* We could add the complexity of filling the entire transmit
* buffer, but we would just wait longer between accesses......
*/
for (i = 0; i < count; i++, string++) {
/* Wait for transmitter fifo to empty.
* Ready indicates output is ready, and xmt is doing
* that, not that it is ready for us to send.
*/
while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
;
/* Send the character out.
* If the buffer address is in the CPM DPRAM, don't
* convert it.
*/
cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
pinfo);
*cpm_outp_addr = *string;
out_be16(&bdp->cbd_datlen, 1);
setbits16(&bdp->cbd_sc, BD_SC_READY);
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
bdp = bdbase;
else
bdp++;
/* if a LF, also do CR... */
if (handle_linefeed && *string == 10) {
while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
;
cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
pinfo);
*cpm_outp_addr = 13;
out_be16(&bdp->cbd_datlen, 1);
setbits16(&bdp->cbd_sc, BD_SC_READY);
if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
bdp = bdbase;
else
bdp++;
}
}
/*
* Finally, Wait for transmitter & holding register to empty
* and restore the IER
*/
while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
;
pinfo->tx_cur = bdp;
}
#endif
#ifdef CONFIG_CONSOLE_POLL
/* Serial polling routines for writing and reading from the uart while
* in an interrupt or debug context.
*/
#define GDB_BUF_SIZE 512 /* power of 2, please */
static char poll_buf[GDB_BUF_SIZE];
static char *pollp;
static int poll_chars;
static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo)
{
u_char c, *cp;
volatile cbd_t *bdp;
int i;
/* Get the address of the host memory buffer.
*/
bdp = pinfo->rx_cur;
if (bdp->cbd_sc & BD_SC_EMPTY)
return NO_POLL_CHAR;
/* If the buffer address is in the CPM DPRAM, don't
* convert it.
*/
cp = cpm2cpu_addr(bdp->cbd_bufaddr, pinfo);
if (obuf) {
i = c = bdp->cbd_datlen;
while (i-- > 0)
*obuf++ = *cp++;
} else
c = *cp;
bdp->cbd_sc &= ~(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID);
bdp->cbd_sc |= BD_SC_EMPTY;
if (bdp->cbd_sc & BD_SC_WRAP)
bdp = pinfo->rx_bd_base;
else
bdp++;
pinfo->rx_cur = (cbd_t *)bdp;
return (int)c;
}
static int cpm_get_poll_char(struct uart_port *port)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
if (!serial_polled) {
serial_polled = 1;
poll_chars = 0;
}
if (poll_chars <= 0) {
int ret = poll_wait_key(poll_buf, pinfo);
if (ret == NO_POLL_CHAR)
return ret;
poll_chars = ret;
pollp = poll_buf;
}
poll_chars--;
return *pollp++;
}
static void cpm_put_poll_char(struct uart_port *port,
unsigned char c)
{
struct uart_cpm_port *pinfo =
container_of(port, struct uart_cpm_port, port);
static char ch[2];
ch[0] = (char)c;
cpm_uart_early_write(pinfo, ch, 1, false);
}
#endif /* CONFIG_CONSOLE_POLL */
static const struct uart_ops cpm_uart_pops = {
.tx_empty = cpm_uart_tx_empty,
.set_mctrl = cpm_uart_set_mctrl,
.get_mctrl = cpm_uart_get_mctrl,
.stop_tx = cpm_uart_stop_tx,
.start_tx = cpm_uart_start_tx,
.stop_rx = cpm_uart_stop_rx,
.break_ctl = cpm_uart_break_ctl,
.startup = cpm_uart_startup,
.shutdown = cpm_uart_shutdown,
.set_termios = cpm_uart_set_termios,
.type = cpm_uart_type,
.release_port = cpm_uart_release_port,
.request_port = cpm_uart_request_port,
.config_port = cpm_uart_config_port,
.verify_port = cpm_uart_verify_port,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = cpm_get_poll_char,
.poll_put_char = cpm_put_poll_char,
#endif
};
struct uart_cpm_port cpm_uart_ports[UART_NR];
static int cpm_uart_init_port(struct device_node *np,
struct uart_cpm_port *pinfo)
{
const u32 *data;
void __iomem *mem, *pram;
int len;
int ret;
int i;
data = of_get_property(np, "clock", NULL);
if (data) {
struct clk *clk = clk_get(NULL, (const char*)data);
if (!IS_ERR(clk))
pinfo->clk = clk;
}
if (!pinfo->clk) {
data = of_get_property(np, "fsl,cpm-brg", &len);
if (!data || len != 4) {
printk(KERN_ERR "CPM UART %s has no/invalid "
"fsl,cpm-brg property.\n", np->name);
return -EINVAL;
}
pinfo->brg = *data;
}
data = of_get_property(np, "fsl,cpm-command", &len);
if (!data || len != 4) {
printk(KERN_ERR "CPM UART %s has no/invalid "
"fsl,cpm-command property.\n", np->name);
return -EINVAL;
}
pinfo->command = *data;
mem = of_iomap(np, 0);
if (!mem)
return -ENOMEM;
if (of_device_is_compatible(np, "fsl,cpm1-scc-uart") ||
of_device_is_compatible(np, "fsl,cpm2-scc-uart")) {
pinfo->sccp = mem;
pinfo->sccup = pram = cpm_uart_map_pram(pinfo, np);
} else if (of_device_is_compatible(np, "fsl,cpm1-smc-uart") ||
of_device_is_compatible(np, "fsl,cpm2-smc-uart")) {
pinfo->flags |= FLAG_SMC;
pinfo->smcp = mem;
pinfo->smcup = pram = cpm_uart_map_pram(pinfo, np);
} else {
ret = -ENODEV;
goto out_mem;
}
if (!pram) {
ret = -ENOMEM;
goto out_mem;
}
pinfo->tx_nrfifos = TX_NUM_FIFO;
pinfo->tx_fifosize = TX_BUF_SIZE;
pinfo->rx_nrfifos = RX_NUM_FIFO;
pinfo->rx_fifosize = RX_BUF_SIZE;
pinfo->port.uartclk = ppc_proc_freq;
pinfo->port.mapbase = (unsigned long)mem;
pinfo->port.type = PORT_CPM;
pinfo->port.ops = &cpm_uart_pops,
pinfo->port.iotype = UPIO_MEM;
pinfo->port.fifosize = pinfo->tx_nrfifos * pinfo->tx_fifosize;
spin_lock_init(&pinfo->port.lock);
pinfo->port.irq = irq_of_parse_and_map(np, 0);
if (pinfo->port.irq == NO_IRQ) {
ret = -EINVAL;
goto out_pram;
}
for (i = 0; i < NUM_GPIOS; i++) {
int gpio;
pinfo->gpios[i] = -1;
gpio = of_get_gpio(np, i);
if (gpio_is_valid(gpio)) {
ret = gpio_request(gpio, "cpm_uart");
if (ret) {
pr_err("can't request gpio #%d: %d\n", i, ret);
continue;
}
if (i == GPIO_RTS || i == GPIO_DTR)
ret = gpio_direction_output(gpio, 0);
else
ret = gpio_direction_input(gpio);
if (ret) {
pr_err("can't set direction for gpio #%d: %d\n",
i, ret);
gpio_free(gpio);
continue;
}
pinfo->gpios[i] = gpio;
}
}
#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
udbg_putc = NULL;
#endif
return cpm_uart_request_port(&pinfo->port);
out_pram:
cpm_uart_unmap_pram(pinfo, pram);
out_mem:
iounmap(mem);
return ret;
}
#ifdef CONFIG_SERIAL_CPM_CONSOLE
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*
* Note that this is called with interrupts already disabled
*/
static void cpm_uart_console_write(struct console *co, const char *s,
u_int count)
{
struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index];
unsigned long flags;
int nolock = oops_in_progress;
if (unlikely(nolock)) {
local_irq_save(flags);
} else {
spin_lock_irqsave(&pinfo->port.lock, flags);
}
cpm_uart_early_write(pinfo, s, count, true);
if (unlikely(nolock)) {
local_irq_restore(flags);
} else {
spin_unlock_irqrestore(&pinfo->port.lock, flags);
}
}
static int __init cpm_uart_console_setup(struct console *co, char *options)
{
int baud = 38400;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
struct uart_cpm_port *pinfo;
struct uart_port *port;
struct device_node *np;
int i = 0;
if (co->index >= UART_NR) {
printk(KERN_ERR "cpm_uart: console index %d too high\n",
co->index);
return -ENODEV;
}
for_each_node_by_type(np, "serial") {
if (!of_device_is_compatible(np, "fsl,cpm1-smc-uart") &&
!of_device_is_compatible(np, "fsl,cpm1-scc-uart") &&
!of_device_is_compatible(np, "fsl,cpm2-smc-uart") &&
!of_device_is_compatible(np, "fsl,cpm2-scc-uart"))
continue;
if (i++ == co->index)
break;
}
if (!np)
return -ENODEV;
pinfo = &cpm_uart_ports[co->index];
pinfo->flags |= FLAG_CONSOLE;
port = &pinfo->port;
ret = cpm_uart_init_port(np, pinfo);
of_node_put(np);
if (ret)
return ret;
if (options) {
uart_parse_options(options, &baud, &parity, &bits, &flow);
} else {
if ((baud = uart_baudrate()) == -1)
baud = 9600;
}
if (IS_SMC(pinfo)) {
out_be16(&pinfo->smcup->smc_brkcr, 0);
cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
} else {
out_be16(&pinfo->sccup->scc_brkcr, 0);
cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
}
ret = cpm_uart_allocbuf(pinfo, 1);
if (ret)
return ret;
cpm_uart_initbd(pinfo);
if (IS_SMC(pinfo))
cpm_uart_init_smc(pinfo);
else
cpm_uart_init_scc(pinfo);
uart_set_options(port, co, baud, parity, bits, flow);
cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
return 0;
}
static struct uart_driver cpm_reg;
static struct console cpm_scc_uart_console = {
.name = "ttyCPM",
.write = cpm_uart_console_write,
.device = uart_console_device,
.setup = cpm_uart_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &cpm_reg,
};
static int __init cpm_uart_console_init(void)
{
register_console(&cpm_scc_uart_console);
return 0;
}
console_initcall(cpm_uart_console_init);
#define CPM_UART_CONSOLE &cpm_scc_uart_console
#else
#define CPM_UART_CONSOLE NULL
#endif
static struct uart_driver cpm_reg = {
.owner = THIS_MODULE,
.driver_name = "ttyCPM",
.dev_name = "ttyCPM",
.major = SERIAL_CPM_MAJOR,
.minor = SERIAL_CPM_MINOR,
.cons = CPM_UART_CONSOLE,
.nr = UART_NR,
};
static int probe_index;
static int cpm_uart_probe(struct platform_device *ofdev)
{
int index = probe_index++;
struct uart_cpm_port *pinfo = &cpm_uart_ports[index];
int ret;
pinfo->port.line = index;
if (index >= UART_NR)
return -ENODEV;
platform_set_drvdata(ofdev, pinfo);
/* initialize the device pointer for the port */
pinfo->port.dev = &ofdev->dev;
ret = cpm_uart_init_port(ofdev->dev.of_node, pinfo);
if (ret)
return ret;
return uart_add_one_port(&cpm_reg, &pinfo->port);
}
static int cpm_uart_remove(struct platform_device *ofdev)
{
struct uart_cpm_port *pinfo = platform_get_drvdata(ofdev);
return uart_remove_one_port(&cpm_reg, &pinfo->port);
}
static const struct of_device_id cpm_uart_match[] = {
{
.compatible = "fsl,cpm1-smc-uart",
},
{
.compatible = "fsl,cpm1-scc-uart",
},
{
.compatible = "fsl,cpm2-smc-uart",
},
{
.compatible = "fsl,cpm2-scc-uart",
},
{}
};
MODULE_DEVICE_TABLE(of, cpm_uart_match);
static struct platform_driver cpm_uart_driver = {
.driver = {
.name = "cpm_uart",
.of_match_table = cpm_uart_match,
},
.probe = cpm_uart_probe,
.remove = cpm_uart_remove,
};
static int __init cpm_uart_init(void)
{
int ret = uart_register_driver(&cpm_reg);
if (ret)
return ret;
ret = platform_driver_register(&cpm_uart_driver);
if (ret)
uart_unregister_driver(&cpm_reg);
return ret;
}
static void __exit cpm_uart_exit(void)
{
platform_driver_unregister(&cpm_uart_driver);
uart_unregister_driver(&cpm_reg);
}
module_init(cpm_uart_init);
module_exit(cpm_uart_exit);
MODULE_AUTHOR("Kumar Gala/Antoniou Pantelis");
MODULE_DESCRIPTION("CPM SCC/SMC port driver $Revision: 0.01 $");
MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV(SERIAL_CPM_MAJOR, SERIAL_CPM_MINOR);