summaryrefslogtreecommitdiff
path: root/drivers/tty/serial/cpm_uart.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/tty/serial/cpm_uart.c')
-rw-r--r--drivers/tty/serial/cpm_uart.c1612
1 files changed, 1612 insertions, 0 deletions
diff --git a/drivers/tty/serial/cpm_uart.c b/drivers/tty/serial/cpm_uart.c
new file mode 100644
index 000000000000..626423022d62
--- /dev/null
+++ b/drivers/tty/serial/cpm_uart.c
@@ -0,0 +1,1612 @@
+// 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/memblock.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/gpio/consumer.h>
+#include <linux/clk.h>
+
+#include <sysdev/fsl_soc.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/delay.h>
+#include <asm/udbg.h>
+
+#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_initbd(struct uart_cpm_port *pinfo);
+
+/**************************************************************/
+
+#define HW_BUF_SPD_THRESHOLD 2400
+
+static void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
+{
+ cpm_command(port->command, cmd);
+}
+
+/*
+ * 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])
+ gpiod_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS));
+
+ if (pinfo->gpios[GPIO_DTR])
+ gpiod_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]) {
+ if (gpiod_get_value(pinfo->gpios[GPIO_CTS]))
+ mctrl &= ~TIOCM_CTS;
+ }
+
+ if (pinfo->gpios[GPIO_DSR]) {
+ if (gpiod_get_value(pinfo->gpios[GPIO_DSR]))
+ mctrl &= ~TIOCM_DSR;
+ }
+
+ if (pinfo->gpios[GPIO_DCD]) {
+ if (gpiod_get_value(pinfo->gpios[GPIO_DCD]))
+ mctrl &= ~TIOCM_CAR;
+ }
+
+ if (pinfo->gpios[GPIO_RI]) {
+ if (!gpiod_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;
+ }
+ port->sysrq = 0;
+ 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,
+ const struct ktermios *old)
+{
+ int baud;
+ unsigned long flags;
+ u16 cval, scval, prev_mode;
+ 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 || port->flags & UPF_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;
+
+ cval = 0;
+ scval = 0;
+
+ if (termios->c_cflag & CSTOPB) {
+ cval |= SMCMR_SL; /* Two stops */
+ scval |= SCU_PSMR_SL;
+ }
+
+ if (termios->c_cflag & PARENB) {
+ cval |= SMCMR_PEN;
+ scval |= SCU_PSMR_PEN;
+ 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
+ */
+ 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);
+
+ if (IS_SMC(pinfo)) {
+ unsigned int bits = tty_get_frame_size(termios->c_cflag);
+
+ /*
+ * 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.
+ * Character length programmed into the register is frame bits minus 1.
+ */
+ out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits - 1) | cval |
+ SMCMR_SM_UART | prev_mode);
+ } else {
+ unsigned int bits = tty_get_char_size(termios->c_cflag);
+
+ out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
+ out_be16(&pinfo->sccup->scc_maxidl, maxidl);
+ out_be16(&sccp->scc_psmr, (UART_LCR_WLEN(bits) << 12) | scval);
+ }
+
+ if (pinfo->clk)
+ clk_set_rate(pinfo->clk, baud);
+ else
+ cpm_setbrg(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) && !uart_circ_empty(xmit)) {
+ count = 0;
+ p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
+ while (count < pinfo->tx_fifosize) {
+ *p++ = xmit->buf[xmit->tail];
+ uart_xmit_advance(port, 1);
+ count++;
+ if (uart_circ_empty(xmit))
+ 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.
+ */
+
+ out_8(&sup->scc_genscc.scc_rfcr, CPMFCR_GBL | CPMFCR_EB);
+ out_8(&sup->scc_genscc.scc_tfcr, CPMFCR_GBL | CPMFCR_EB);
+
+ 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.
+ */
+ out_8(&up->smc_rfcr, CPMFCR_GBL | CPMFCR_EB);
+ out_8(&up->smc_tfcr, CPMFCR_GBL | CPMFCR_EB);
+
+ /* 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);
+}
+
+/*
+ * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
+ * receive buffer descriptors from dual port ram, and a character
+ * buffer area from host mem. If we are allocating for the console we need
+ * to do it from bootmem
+ */
+static int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
+{
+ int dpmemsz, memsz;
+ u8 __iomem *dp_mem;
+ unsigned long dp_offset;
+ u8 *mem_addr;
+ dma_addr_t dma_addr = 0;
+
+ pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
+
+ dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
+ dp_offset = cpm_muram_alloc(dpmemsz, 8);
+ if (IS_ERR_VALUE(dp_offset)) {
+ pr_err("%s: could not allocate buffer descriptors\n", __func__);
+ return -ENOMEM;
+ }
+
+ dp_mem = cpm_muram_addr(dp_offset);
+
+ memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
+ L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
+ if (IS_ENABLED(CONFIG_CPM1) && is_con) {
+ /* was hostalloc but changed cause it blows away the */
+ /* large tlb mapping when pinning the kernel area */
+ mem_addr = (u8 __force *)cpm_muram_addr(cpm_muram_alloc(memsz, 8));
+ dma_addr = cpm_muram_dma((void __iomem *)mem_addr);
+ } else if (is_con) {
+ mem_addr = kzalloc(memsz, GFP_NOWAIT);
+ dma_addr = virt_to_bus(mem_addr);
+ } else {
+ mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
+ GFP_KERNEL);
+ }
+
+ if (!mem_addr) {
+ cpm_muram_free(dp_offset);
+ pr_err("%s: could not allocate coherent memory\n", __func__);
+ return -ENOMEM;
+ }
+
+ pinfo->dp_addr = dp_offset;
+ pinfo->mem_addr = mem_addr;
+ pinfo->dma_addr = dma_addr;
+ pinfo->mem_size = memsz;
+
+ pinfo->rx_buf = mem_addr;
+ pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
+ * pinfo->rx_fifosize);
+
+ pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
+ pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
+
+ return 0;
+}
+
+static void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
+{
+ dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
+ pinfo->rx_fifosize) +
+ L1_CACHE_ALIGN(pinfo->tx_nrfifos *
+ pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
+ pinfo->dma_addr);
+
+ cpm_muram_free(pinfo->dp_addr);
+}
+
+/*
+ * 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);
+}
+
+#ifdef CONFIG_SERIAL_CPM_CONSOLE
+static struct uart_port *udbg_port;
+
+static void udbg_cpm_putc(char c)
+{
+ if (c == '\n')
+ cpm_put_poll_char(udbg_port, '\r');
+ cpm_put_poll_char(udbg_port, c);
+}
+
+static int udbg_cpm_getc_poll(void)
+{
+ int c = cpm_get_poll_char(udbg_port);
+
+ return c == NO_POLL_CHAR ? -1 : c;
+}
+
+static int udbg_cpm_getc(void)
+{
+ int c;
+