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ucc_uart.c
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ucc_uart.c
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/*
* Freescale QUICC Engine UART device driver
*
* Author: Timur Tabi <timur@freescale.com>
*
* Copyright 2007 Freescale Semiconductor, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*
* This driver adds support for UART devices via Freescale's QUICC Engine
* found on some Freescale SOCs.
*
* If Soft-UART support is needed but not already present, then this driver
* will request and upload the "Soft-UART" microcode upon probe. The
* filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X"
* is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC,
* (e.g. "11" for 1.1).
*/
#include <linux/module.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/io.h>
#include <linux/of_platform.h>
#include <linux/dma-mapping.h>
#include <linux/fs_uart_pd.h>
#include <asm/ucc_slow.h>
#include <linux/firmware.h>
#include <asm/reg.h>
/*
* The GUMR flag for Soft UART. This would normally be defined in qe.h,
* but Soft-UART is a hack and we want to keep everything related to it in
* this file.
*/
#define UCC_SLOW_GUMR_H_SUART 0x00004000 /* Soft-UART */
/*
* soft_uart is 1 if we need to use Soft-UART mode
*/
static int soft_uart;
/*
* firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
*/
static int firmware_loaded;
/* Enable this macro to configure all serial ports in internal loopback
mode */
/* #define LOOPBACK */
/* The major and minor device numbers are defined in
* http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE
* UART, we have major number 204 and minor numbers 46 - 49, which are the
* same as for the CPM2. This decision was made because no Freescale part
* has both a CPM and a QE.
*/
#define SERIAL_QE_MAJOR 204
#define SERIAL_QE_MINOR 46
/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
#define UCC_MAX_UART 4
/* The number of buffer descriptors for receiving characters. */
#define RX_NUM_FIFO 4
/* The number of buffer descriptors for transmitting characters. */
#define TX_NUM_FIFO 4
/* The maximum size of the character buffer for a single RX BD. */
#define RX_BUF_SIZE 32
/* The maximum size of the character buffer for a single TX BD. */
#define TX_BUF_SIZE 32
/*
* The number of jiffies to wait after receiving a close command before the
* device is actually closed. This allows the last few characters to be
* sent over the wire.
*/
#define UCC_WAIT_CLOSING 100
struct ucc_uart_pram {
struct ucc_slow_pram common;
u8 res1[8]; /* reserved */
__be16 maxidl; /* Maximum idle chars */
__be16 idlc; /* temp idle counter */
__be16 brkcr; /* Break count register */
__be16 parec; /* receive parity error counter */
__be16 frmec; /* receive framing error counter */
__be16 nosec; /* receive noise counter */
__be16 brkec; /* receive break condition counter */
__be16 brkln; /* last received break length */
__be16 uaddr[2]; /* UART address character 1 & 2 */
__be16 rtemp; /* Temp storage */
__be16 toseq; /* Transmit out of sequence char */
__be16 cchars[8]; /* control characters 1-8 */
__be16 rccm; /* receive control character mask */
__be16 rccr; /* receive control character register */
__be16 rlbc; /* receive last break character */
__be16 res2; /* reserved */
__be32 res3; /* reserved, should be cleared */
u8 res4; /* reserved, should be cleared */
u8 res5[3]; /* reserved, should be cleared */
__be32 res6; /* reserved, should be cleared */
__be32 res7; /* reserved, should be cleared */
__be32 res8; /* reserved, should be cleared */
__be32 res9; /* reserved, should be cleared */
__be32 res10; /* reserved, should be cleared */
__be32 res11; /* reserved, should be cleared */
__be32 res12; /* reserved, should be cleared */
__be32 res13; /* reserved, should be cleared */
/* The rest is for Soft-UART only */
__be16 supsmr; /* 0x90, Shadow UPSMR */
__be16 res92; /* 0x92, reserved, initialize to 0 */
__be32 rx_state; /* 0x94, RX state, initialize to 0 */
__be32 rx_cnt; /* 0x98, RX count, initialize to 0 */
u8 rx_length; /* 0x9C, Char length, set to 1+CL+PEN+1+SL */
u8 rx_bitmark; /* 0x9D, reserved, initialize to 0 */
u8 rx_temp_dlst_qe; /* 0x9E, reserved, initialize to 0 */
u8 res14[0xBC - 0x9F]; /* reserved */
__be32 dump_ptr; /* 0xBC, Dump pointer */
__be32 rx_frame_rem; /* 0xC0, reserved, initialize to 0 */
u8 rx_frame_rem_size; /* 0xC4, reserved, initialize to 0 */
u8 tx_mode; /* 0xC5, mode, 0=AHDLC, 1=UART */
__be16 tx_state; /* 0xC6, TX state */
u8 res15[0xD0 - 0xC8]; /* reserved */
__be32 resD0; /* 0xD0, reserved, initialize to 0 */
u8 resD4; /* 0xD4, reserved, initialize to 0 */
__be16 resD5; /* 0xD5, reserved, initialize to 0 */
} __attribute__ ((packed));
/* SUPSMR definitions, for Soft-UART only */
#define UCC_UART_SUPSMR_SL 0x8000
#define UCC_UART_SUPSMR_RPM_MASK 0x6000
#define UCC_UART_SUPSMR_RPM_ODD 0x0000
#define UCC_UART_SUPSMR_RPM_LOW 0x2000
#define UCC_UART_SUPSMR_RPM_EVEN 0x4000
#define UCC_UART_SUPSMR_RPM_HIGH 0x6000
#define UCC_UART_SUPSMR_PEN 0x1000
#define UCC_UART_SUPSMR_TPM_MASK 0x0C00
#define UCC_UART_SUPSMR_TPM_ODD 0x0000
#define UCC_UART_SUPSMR_TPM_LOW 0x0400
#define UCC_UART_SUPSMR_TPM_EVEN 0x0800
#define UCC_UART_SUPSMR_TPM_HIGH 0x0C00
#define UCC_UART_SUPSMR_FRZ 0x0100
#define UCC_UART_SUPSMR_UM_MASK 0x00c0
#define UCC_UART_SUPSMR_UM_NORMAL 0x0000
#define UCC_UART_SUPSMR_UM_MAN_MULTI 0x0040
#define UCC_UART_SUPSMR_UM_AUTO_MULTI 0x00c0
#define UCC_UART_SUPSMR_CL_MASK 0x0030
#define UCC_UART_SUPSMR_CL_8 0x0030
#define UCC_UART_SUPSMR_CL_7 0x0020
#define UCC_UART_SUPSMR_CL_6 0x0010
#define UCC_UART_SUPSMR_CL_5 0x0000
#define UCC_UART_TX_STATE_AHDLC 0x00
#define UCC_UART_TX_STATE_UART 0x01
#define UCC_UART_TX_STATE_X1 0x00
#define UCC_UART_TX_STATE_X16 0x80
#define UCC_UART_PRAM_ALIGNMENT 0x100
#define UCC_UART_SIZE_OF_BD UCC_SLOW_SIZE_OF_BD
#define NUM_CONTROL_CHARS 8
/* Private per-port data structure */
struct uart_qe_port {
struct uart_port port;
struct ucc_slow __iomem *uccp;
struct ucc_uart_pram __iomem *uccup;
struct ucc_slow_info us_info;
struct ucc_slow_private *us_private;
struct device_node *np;
unsigned int ucc_num; /* First ucc is 0, not 1 */
u16 rx_nrfifos;
u16 rx_fifosize;
u16 tx_nrfifos;
u16 tx_fifosize;
int wait_closing;
u32 flags;
struct qe_bd *rx_bd_base;
struct qe_bd *rx_cur;
struct qe_bd *tx_bd_base;
struct qe_bd *tx_cur;
unsigned char *tx_buf;
unsigned char *rx_buf;
void *bd_virt; /* virtual address of the BD buffers */
dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
unsigned int bd_size; /* size of BD buffer space */
};
static struct uart_driver ucc_uart_driver = {
.owner = THIS_MODULE,
.driver_name = "ucc_uart",
.dev_name = "ttyQE",
.major = SERIAL_QE_MAJOR,
.minor = SERIAL_QE_MINOR,
.nr = UCC_MAX_UART,
};
/*
* Virtual to physical address translation.
*
* Given the virtual address for a character buffer, this function returns
* the physical (DMA) equivalent.
*/
static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
{
if (likely((addr >= qe_port->bd_virt)) &&
(addr < (qe_port->bd_virt + qe_port->bd_size)))
return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
/* something nasty happened */
printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
BUG();
return 0;
}
/*
* Physical to virtual address translation.
*
* Given the physical (DMA) address for a character buffer, this function
* returns the virtual equivalent.
*/
static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
{
/* sanity check */
if (likely((addr >= qe_port->bd_dma_addr) &&
(addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
/* something nasty happened */
printk(KERN_ERR "%s: addr=%x\n", __func__, addr);
BUG();
return NULL;
}
/*
* Return 1 if the QE is done transmitting all buffers for this port
*
* This function scans each BD in sequence. If we find a BD that is not
* ready (READY=1), then we return 0 indicating that the QE is still sending
* data. If we reach the last BD (WRAP=1), then we know we've scanned
* the entire list, and all BDs are done.
*/
static unsigned int qe_uart_tx_empty(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
struct qe_bd *bdp = qe_port->tx_bd_base;
while (1) {
if (in_be16(&bdp->status) & BD_SC_READY)
/* This BD is not done, so return "not done" */
return 0;
if (in_be16(&bdp->status) & BD_SC_WRAP)
/*
* This BD is done and it's the last one, so return
* "done"
*/
return 1;
bdp++;
};
}
/*
* Set the modem control lines
*
* Although the QE can control the modem control lines (e.g. CTS), we
* don't need that support. This function must exist, however, otherwise
* the kernel will panic.
*/
void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
}
/*
* Get the current modem control line status
*
* Although the QE can control the modem control lines (e.g. CTS), this
* driver currently doesn't support that, so we always return Carrier
* Detect, Data Set Ready, and Clear To Send.
*/
static unsigned int qe_uart_get_mctrl(struct uart_port *port)
{
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
}
/*
* Disable the transmit interrupt.
*
* Although this function is called "stop_tx", it does not actually stop
* transmission of data. Instead, it tells the QE to not generate an
* interrupt when the UCC is finished sending characters.
*/
static void qe_uart_stop_tx(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
}
/*
* Transmit as many characters to the HW as possible.
*
* This function will attempt to stuff of all the characters from the
* kernel's transmit buffer into TX BDs.
*
* A return value of non-zero indicates that it sucessfully stuffed all
* characters from the kernel buffer.
*
* A return value of zero indicates that there are still characters in the
* kernel's buffer that have not been transmitted, but there are no more BDs
* available. This function should be called again after a BD has been made
* available.
*/
static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
{
struct qe_bd *bdp;
unsigned char *p;
unsigned int count;
struct uart_port *port = &qe_port->port;
struct circ_buf *xmit = &port->info->xmit;
bdp = qe_port->rx_cur;
/* Handle xon/xoff */
if (port->x_char) {
/* Pick next descriptor and fill from buffer */
bdp = qe_port->tx_cur;
p = qe2cpu_addr(bdp->buf, qe_port);
*p++ = port->x_char;
out_be16(&bdp->length, 1);
setbits16(&bdp->status, BD_SC_READY);
/* Get next BD. */
if (in_be16(&bdp->status) & BD_SC_WRAP)
bdp = qe_port->tx_bd_base;
else
bdp++;
qe_port->tx_cur = bdp;
port->icount.tx++;
port->x_char = 0;
return 1;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
qe_uart_stop_tx(port);
return 0;
}
/* Pick next descriptor and fill from buffer */
bdp = qe_port->tx_cur;
while (!(in_be16(&bdp->status) & BD_SC_READY) &&
(xmit->tail != xmit->head)) {
count = 0;
p = qe2cpu_addr(bdp->buf, qe_port);
while (count < qe_port->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->length, count);
setbits16(&bdp->status, BD_SC_READY);
/* Get next BD. */
if (in_be16(&bdp->status) & BD_SC_WRAP)
bdp = qe_port->tx_bd_base;
else
bdp++;
}
qe_port->tx_cur = bdp;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit)) {
/* The kernel buffer is empty, so turn off TX interrupts. We
don't need to be told when the QE is finished transmitting
the data. */
qe_uart_stop_tx(port);
return 0;
}
return 1;
}
/*
* Start transmitting data
*
* This function will start transmitting any available data, if the port
* isn't already transmitting data.
*/
static void qe_uart_start_tx(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
/* If we currently are transmitting, then just return */
if (in_be16(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
return;
/* Otherwise, pump the port and start transmission */
if (qe_uart_tx_pump(qe_port))
setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
}
/*
* Stop transmitting data
*/
static void qe_uart_stop_rx(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
}
/*
* Enable status change interrupts
*
* We don't support status change interrupts, but we need to define this
* function otherwise the kernel will panic.
*/
static void qe_uart_enable_ms(struct uart_port *port)
{
}
/* Start or stop sending break signal
*
* This function controls the sending of a break signal. If break_state=1,
* then we start sending a break signal. If break_state=0, then we stop
* sending the break signal.
*/
static void qe_uart_break_ctl(struct uart_port *port, int break_state)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
if (break_state)
ucc_slow_stop_tx(qe_port->us_private);
else
ucc_slow_restart_tx(qe_port->us_private);
}
/* ISR helper function for receiving character.
*
* This function is called by the ISR to handling receiving characters
*/
static void qe_uart_int_rx(struct uart_qe_port *qe_port)
{
int i;
unsigned char ch, *cp;
struct uart_port *port = &qe_port->port;
struct tty_struct *tty = port->info->port.tty;
struct qe_bd *bdp;
u16 status;
unsigned int flg;
/* Just loop through the closed BDs and copy the characters into
* the buffer.
*/
bdp = qe_port->rx_cur;
while (1) {
status = in_be16(&bdp->status);
/* If this one is empty, then we assume we've read them all */
if (status & BD_SC_EMPTY)
break;
/* get number of characters, and check space in RX buffer */
i = in_be16(&bdp->length);
/* If we don't have enough room in RX buffer for the entire BD,
* then we try later, which will be the next RX interrupt.
*/
if (tty_buffer_request_room(tty, i) < i) {
dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
return;
}
/* get pointer */
cp = qe2cpu_addr(bdp->buf, qe_port);
/* loop through the buffer */
while (i-- > 0) {
ch = *cp++;
port->icount.rx++;
flg = TTY_NORMAL;
if (!i && status &
(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
goto handle_error;
if (uart_handle_sysrq_char(port, ch))
continue;
error_return:
tty_insert_flip_char(tty, ch, flg);
}
/* This BD is ready to be used again. Clear status. get next */
clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
if (in_be16(&bdp->status) & BD_SC_WRAP)
bdp = qe_port->rx_bd_base;
else
bdp++;
}
/* Write back buffer pointer */
qe_port->rx_cur = bdp;
/* Activate BH processing */
tty_flip_buffer_push(tty);
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)
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
#ifdef SUPPORT_SYSRQ
port->sysrq = 0;
#endif
goto error_return;
}
/* Interrupt handler
*
* This interrupt handler is called after a BD is processed.
*/
static irqreturn_t qe_uart_int(int irq, void *data)
{
struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
struct ucc_slow __iomem *uccp = qe_port->uccp;
u16 events;
/* Clear the interrupts */
events = in_be16(&uccp->ucce);
out_be16(&uccp->ucce, events);
if (events & UCC_UART_UCCE_BRKE)
uart_handle_break(&qe_port->port);
if (events & UCC_UART_UCCE_RX)
qe_uart_int_rx(qe_port);
if (events & UCC_UART_UCCE_TX)
qe_uart_tx_pump(qe_port);
return events ? IRQ_HANDLED : IRQ_NONE;
}
/* Initialize buffer descriptors
*
* This function initializes all of the RX and TX buffer descriptors.
*/
static void qe_uart_initbd(struct uart_qe_port *qe_port)
{
int i;
void *bd_virt;
struct qe_bd *bdp;
/* Set the physical address of the host memory buffers in the buffer
* descriptors, and the virtual address for us to work with.
*/
bd_virt = qe_port->bd_virt;
bdp = qe_port->rx_bd_base;
qe_port->rx_cur = qe_port->rx_bd_base;
for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
out_be16(&bdp->length, 0);
bd_virt += qe_port->rx_fifosize;
bdp++;
}
/* */
out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
out_be16(&bdp->length, 0);
/* Set the physical address of the host memory
* buffers in the buffer descriptors, and the
* virtual address for us to work with.
*/
bd_virt = qe_port->bd_virt +
L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
qe_port->tx_cur = qe_port->tx_bd_base;
bdp = qe_port->tx_bd_base;
for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
out_be16(&bdp->status, BD_SC_INTRPT);
out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
out_be16(&bdp->length, 0);
bd_virt += qe_port->tx_fifosize;
bdp++;
}
/* Loopback requires the preamble bit to be set on the first TX BD */
#ifdef LOOPBACK
setbits16(&qe_port->tx_cur->status, BD_SC_P);
#endif
out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
out_be16(&bdp->length, 0);
}
/*
* Initialize a UCC for UART.
*
* This function configures a given UCC to be used as a UART device. Basic
* UCC initialization is handled in qe_uart_request_port(). This function
* does all the UART-specific stuff.
*/
static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
{
u32 cecr_subblock;
struct ucc_slow __iomem *uccp = qe_port->uccp;
struct ucc_uart_pram *uccup = qe_port->uccup;
unsigned int i;
/* First, disable TX and RX in the UCC */
ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
/* Program the UCC UART parameter RAM */
out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
out_be16(&uccup->maxidl, 0x10);
out_be16(&uccup->brkcr, 1);
out_be16(&uccup->parec, 0);
out_be16(&uccup->frmec, 0);
out_be16(&uccup->nosec, 0);
out_be16(&uccup->brkec, 0);
out_be16(&uccup->uaddr[0], 0);
out_be16(&uccup->uaddr[1], 0);
out_be16(&uccup->toseq, 0);
for (i = 0; i < 8; i++)
out_be16(&uccup->cchars[i], 0xC000);
out_be16(&uccup->rccm, 0xc0ff);
/* Configure the GUMR registers for UART */
if (soft_uart)
/* Soft-UART requires a 1X multiplier for TX */
clrsetbits_be32(&uccp->gumr_l,
UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
UCC_SLOW_GUMR_L_RDCR_MASK,
UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
UCC_SLOW_GUMR_L_RDCR_16);
else
clrsetbits_be32(&uccp->gumr_l,
UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
UCC_SLOW_GUMR_L_RDCR_MASK,
UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
UCC_SLOW_GUMR_L_RDCR_16);
clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
#ifdef LOOPBACK
clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
UCC_SLOW_GUMR_L_DIAG_LOOP);
clrsetbits_be32(&uccp->gumr_h,
UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
UCC_SLOW_GUMR_H_CDS);
#endif
/* Enable rx interrupts and clear all pending events. */
out_be16(&uccp->uccm, 0);
out_be16(&uccp->ucce, 0xffff);
out_be16(&uccp->udsr, 0x7e7e);
/* Initialize UPSMR */
out_be16(&uccp->upsmr, 0);
if (soft_uart) {
out_be16(&uccup->supsmr, 0x30);
out_be16(&uccup->res92, 0);
out_be32(&uccup->rx_state, 0);
out_be32(&uccup->rx_cnt, 0);
out_8(&uccup->rx_bitmark, 0);
out_8(&uccup->rx_length, 10);
out_be32(&uccup->dump_ptr, 0x4000);
out_8(&uccup->rx_temp_dlst_qe, 0);
out_be32(&uccup->rx_frame_rem, 0);
out_8(&uccup->rx_frame_rem_size, 0);
/* Soft-UART requires TX to be 1X */
out_8(&uccup->tx_mode,
UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
out_be16(&uccup->tx_state, 0);
out_8(&uccup->resD4, 0);
out_be16(&uccup->resD5, 0);
/* Set UART mode.
* Enable receive and transmit.
*/
/* From the microcode errata:
* 1.GUMR_L register, set mode=0010 (QMC).
* 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
* 3.Set GUMR_H[19:20] (Transparent mode)
* 4.Clear GUMR_H[26] (RFW)
* ...
* 6.Receiver must use 16x over sampling
*/
clrsetbits_be32(&uccp->gumr_l,
UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
UCC_SLOW_GUMR_L_RDCR_MASK,
UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
UCC_SLOW_GUMR_L_RDCR_16);
clrsetbits_be32(&uccp->gumr_h,
UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
#ifdef LOOPBACK
clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
UCC_SLOW_GUMR_L_DIAG_LOOP);
clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
UCC_SLOW_GUMR_H_CDS);
#endif
cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
QE_CR_PROTOCOL_UNSPECIFIED, 0);
}
}
/*
* Initialize the port.
*/
static int qe_uart_startup(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
int ret;
/*
* If we're using Soft-UART mode, then we need to make sure the
* firmware has been uploaded first.
*/
if (soft_uart && !firmware_loaded) {
dev_err(port->dev, "Soft-UART firmware not uploaded\n");
return -ENODEV;
}
qe_uart_initbd(qe_port);
qe_uart_init_ucc(qe_port);
/* Install interrupt handler. */
ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
qe_port);
if (ret) {
dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
return ret;
}
/* Startup rx-int */
setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
return 0;
}
/*
* Shutdown the port.
*/
static void qe_uart_shutdown(struct uart_port *port)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
struct ucc_slow __iomem *uccp = qe_port->uccp;
unsigned int timeout = 20;
/* Disable RX and TX */
/* Wait for all the BDs marked sent */
while (!qe_uart_tx_empty(port)) {
if (!--timeout) {
dev_warn(port->dev, "shutdown timeout\n");
break;
}
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(2);
}
if (qe_port->wait_closing) {
/* Wait a bit longer */
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(qe_port->wait_closing);
}
/* Stop uarts */
ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
/* Shut them really down and reinit buffer descriptors */
ucc_slow_graceful_stop_tx(qe_port->us_private);
qe_uart_initbd(qe_port);
free_irq(port->irq, qe_port);
}
/*
* Set the serial port parameters.
*/
static void qe_uart_set_termios(struct uart_port *port,
struct ktermios *termios, struct ktermios *old)
{
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
struct ucc_slow __iomem *uccp = qe_port->uccp;
unsigned int baud;
unsigned long flags;
u16 upsmr = in_be16(&uccp->upsmr);
struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
u16 supsmr = in_be16(&uccup->supsmr);
u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
/* 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.
*/
/* byte size */
upsmr &= UCC_UART_UPSMR_CL_MASK;
supsmr &= UCC_UART_SUPSMR_CL_MASK;
switch (termios->c_cflag & CSIZE) {
case CS5:
upsmr |= UCC_UART_UPSMR_CL_5;
supsmr |= UCC_UART_SUPSMR_CL_5;
char_length += 5;
break;
case CS6:
upsmr |= UCC_UART_UPSMR_CL_6;
supsmr |= UCC_UART_SUPSMR_CL_6;
char_length += 6;
break;
case CS7:
upsmr |= UCC_UART_UPSMR_CL_7;
supsmr |= UCC_UART_SUPSMR_CL_7;
char_length += 7;
break;
default: /* case CS8 */
upsmr |= UCC_UART_UPSMR_CL_8;
supsmr |= UCC_UART_SUPSMR_CL_8;
char_length += 8;
break;
}
/* If CSTOPB is set, we want two stop bits */
if (termios->c_cflag & CSTOPB) {
upsmr |= UCC_UART_UPSMR_SL;
supsmr |= UCC_UART_SUPSMR_SL;
char_length++; /* + SL */
}
if (termios->c_cflag & PARENB) {
upsmr |= UCC_UART_UPSMR_PEN;
supsmr |= UCC_UART_SUPSMR_PEN;
char_length++; /* + PEN */
if (!(termios->c_cflag & PARODD)) {
upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
UCC_UART_UPSMR_TPM_MASK);
upsmr |= UCC_UART_UPSMR_RPM_EVEN |
UCC_UART_UPSMR_TPM_EVEN;
supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
UCC_UART_SUPSMR_TPM_MASK);
supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
UCC_UART_SUPSMR_TPM_EVEN;
}
}
/*
* 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 | 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;
baud = uart_get_baud_rate(port, termios, old, 0, 115200);
/* Do we really need a spinlock here? */
spin_lock_irqsave(&port->lock, flags);
out_be16(&uccp->upsmr, upsmr);
if (soft_uart) {
out_be16(&uccup->supsmr, supsmr);
out_8(&uccup->rx_length, char_length);
/* Soft-UART requires a 1X multiplier for TX */
qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
} else {
qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
}
spin_unlock_irqrestore(&port->lock, flags);
}
/*
* Return a pointer to a string that describes what kind of port this is.
*/
static const char *qe_uart_type(struct uart_port *port)
{
return "QE";
}
/*
* Allocate any memory and I/O resources required by the port.
*/
static int qe_uart_request_port(struct uart_port *port)
{
int ret;
struct uart_qe_port *qe_port =
container_of(port, struct uart_qe_port, port);
struct ucc_slow_info *us_info = &qe_port->us_info;
struct ucc_slow_private *uccs;
unsigned int rx_size, tx_size;
void *bd_virt;
dma_addr_t bd_dma_addr = 0;
ret = ucc_slow_init(us_info, &uccs);
if (ret) {
dev_err(port->dev, "could not initialize UCC%u\n",
qe_port->ucc_num);
return ret;
}
qe_port->us_private = uccs;
qe_port->uccp = uccs->us_regs;