2 * Freescale QUICC Engine UART device driver
4 * Author: Timur Tabi <timur@freescale.com>
6 * Copyright 2007 Freescale Semiconductor, Inc. This file is licensed under
7 * the terms of the GNU General Public License version 2. This program
8 * is licensed "as is" without any warranty of any kind, whether express
11 * This driver adds support for UART devices via Freescale's QUICC Engine
12 * found on some Freescale SOCs.
14 * If Soft-UART support is needed but not already present, then this driver
15 * will request and upload the "Soft-UART" microcode upon probe. The
16 * filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X"
17 * is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC,
18 * (e.g. "11" for 1.1).
21 #include <linux/module.h>
22 #include <linux/serial.h>
23 #include <linux/serial_core.h>
24 #include <linux/slab.h>
25 #include <linux/tty.h>
26 #include <linux/tty_flip.h>
28 #include <linux/of_address.h>
29 #include <linux/of_irq.h>
30 #include <linux/of_platform.h>
31 #include <linux/dma-mapping.h>
33 #include <linux/fs_uart_pd.h>
34 #include <soc/fsl/qe/ucc_slow.h>
36 #include <linux/firmware.h>
40 * The GUMR flag for Soft UART. This would normally be defined in qe.h,
41 * but Soft-UART is a hack and we want to keep everything related to it in
44 #define UCC_SLOW_GUMR_H_SUART 0x00004000 /* Soft-UART */
47 * soft_uart is 1 if we need to use Soft-UART mode
51 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
53 static int firmware_loaded;
55 /* Enable this macro to configure all serial ports in internal loopback
57 /* #define LOOPBACK */
59 /* The major and minor device numbers are defined in
60 * http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE
61 * UART, we have major number 204 and minor numbers 46 - 49, which are the
62 * same as for the CPM2. This decision was made because no Freescale part
63 * has both a CPM and a QE.
65 #define SERIAL_QE_MAJOR 204
66 #define SERIAL_QE_MINOR 46
68 /* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
69 #define UCC_MAX_UART 4
71 /* The number of buffer descriptors for receiving characters. */
74 /* The number of buffer descriptors for transmitting characters. */
77 /* The maximum size of the character buffer for a single RX BD. */
78 #define RX_BUF_SIZE 32
80 /* The maximum size of the character buffer for a single TX BD. */
81 #define TX_BUF_SIZE 32
84 * The number of jiffies to wait after receiving a close command before the
85 * device is actually closed. This allows the last few characters to be
88 #define UCC_WAIT_CLOSING 100
90 struct ucc_uart_pram {
91 struct ucc_slow_pram common;
92 u8 res1[8]; /* reserved */
93 __be16 maxidl; /* Maximum idle chars */
94 __be16 idlc; /* temp idle counter */
95 __be16 brkcr; /* Break count register */
96 __be16 parec; /* receive parity error counter */
97 __be16 frmec; /* receive framing error counter */
98 __be16 nosec; /* receive noise counter */
99 __be16 brkec; /* receive break condition counter */
100 __be16 brkln; /* last received break length */
101 __be16 uaddr[2]; /* UART address character 1 & 2 */
102 __be16 rtemp; /* Temp storage */
103 __be16 toseq; /* Transmit out of sequence char */
104 __be16 cchars[8]; /* control characters 1-8 */
105 __be16 rccm; /* receive control character mask */
106 __be16 rccr; /* receive control character register */
107 __be16 rlbc; /* receive last break character */
108 __be16 res2; /* reserved */
109 __be32 res3; /* reserved, should be cleared */
110 u8 res4; /* reserved, should be cleared */
111 u8 res5[3]; /* reserved, should be cleared */
112 __be32 res6; /* reserved, should be cleared */
113 __be32 res7; /* reserved, should be cleared */
114 __be32 res8; /* reserved, should be cleared */
115 __be32 res9; /* reserved, should be cleared */
116 __be32 res10; /* reserved, should be cleared */
117 __be32 res11; /* reserved, should be cleared */
118 __be32 res12; /* reserved, should be cleared */
119 __be32 res13; /* reserved, should be cleared */
120 /* The rest is for Soft-UART only */
121 __be16 supsmr; /* 0x90, Shadow UPSMR */
122 __be16 res92; /* 0x92, reserved, initialize to 0 */
123 __be32 rx_state; /* 0x94, RX state, initialize to 0 */
124 __be32 rx_cnt; /* 0x98, RX count, initialize to 0 */
125 u8 rx_length; /* 0x9C, Char length, set to 1+CL+PEN+1+SL */
126 u8 rx_bitmark; /* 0x9D, reserved, initialize to 0 */
127 u8 rx_temp_dlst_qe; /* 0x9E, reserved, initialize to 0 */
128 u8 res14[0xBC - 0x9F]; /* reserved */
129 __be32 dump_ptr; /* 0xBC, Dump pointer */
130 __be32 rx_frame_rem; /* 0xC0, reserved, initialize to 0 */
131 u8 rx_frame_rem_size; /* 0xC4, reserved, initialize to 0 */
132 u8 tx_mode; /* 0xC5, mode, 0=AHDLC, 1=UART */
133 __be16 tx_state; /* 0xC6, TX state */
134 u8 res15[0xD0 - 0xC8]; /* reserved */
135 __be32 resD0; /* 0xD0, reserved, initialize to 0 */
136 u8 resD4; /* 0xD4, reserved, initialize to 0 */
137 __be16 resD5; /* 0xD5, reserved, initialize to 0 */
138 } __attribute__ ((packed));
140 /* SUPSMR definitions, for Soft-UART only */
141 #define UCC_UART_SUPSMR_SL 0x8000
142 #define UCC_UART_SUPSMR_RPM_MASK 0x6000
143 #define UCC_UART_SUPSMR_RPM_ODD 0x0000
144 #define UCC_UART_SUPSMR_RPM_LOW 0x2000
145 #define UCC_UART_SUPSMR_RPM_EVEN 0x4000
146 #define UCC_UART_SUPSMR_RPM_HIGH 0x6000
147 #define UCC_UART_SUPSMR_PEN 0x1000
148 #define UCC_UART_SUPSMR_TPM_MASK 0x0C00
149 #define UCC_UART_SUPSMR_TPM_ODD 0x0000
150 #define UCC_UART_SUPSMR_TPM_LOW 0x0400
151 #define UCC_UART_SUPSMR_TPM_EVEN 0x0800
152 #define UCC_UART_SUPSMR_TPM_HIGH 0x0C00
153 #define UCC_UART_SUPSMR_FRZ 0x0100
154 #define UCC_UART_SUPSMR_UM_MASK 0x00c0
155 #define UCC_UART_SUPSMR_UM_NORMAL 0x0000
156 #define UCC_UART_SUPSMR_UM_MAN_MULTI 0x0040
157 #define UCC_UART_SUPSMR_UM_AUTO_MULTI 0x00c0
158 #define UCC_UART_SUPSMR_CL_MASK 0x0030
159 #define UCC_UART_SUPSMR_CL_8 0x0030
160 #define UCC_UART_SUPSMR_CL_7 0x0020
161 #define UCC_UART_SUPSMR_CL_6 0x0010
162 #define UCC_UART_SUPSMR_CL_5 0x0000
164 #define UCC_UART_TX_STATE_AHDLC 0x00
165 #define UCC_UART_TX_STATE_UART 0x01
166 #define UCC_UART_TX_STATE_X1 0x00
167 #define UCC_UART_TX_STATE_X16 0x80
169 #define UCC_UART_PRAM_ALIGNMENT 0x100
171 #define UCC_UART_SIZE_OF_BD UCC_SLOW_SIZE_OF_BD
172 #define NUM_CONTROL_CHARS 8
174 /* Private per-port data structure */
175 struct uart_qe_port {
176 struct uart_port port;
177 struct ucc_slow __iomem *uccp;
178 struct ucc_uart_pram __iomem *uccup;
179 struct ucc_slow_info us_info;
180 struct ucc_slow_private *us_private;
181 struct device_node *np;
182 unsigned int ucc_num; /* First ucc is 0, not 1 */
190 struct qe_bd *rx_bd_base;
191 struct qe_bd *rx_cur;
192 struct qe_bd *tx_bd_base;
193 struct qe_bd *tx_cur;
194 unsigned char *tx_buf;
195 unsigned char *rx_buf;
196 void *bd_virt; /* virtual address of the BD buffers */
197 dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
198 unsigned int bd_size; /* size of BD buffer space */
201 static struct uart_driver ucc_uart_driver = {
202 .owner = THIS_MODULE,
203 .driver_name = "ucc_uart",
205 .major = SERIAL_QE_MAJOR,
206 .minor = SERIAL_QE_MINOR,
211 * Virtual to physical address translation.
213 * Given the virtual address for a character buffer, this function returns
214 * the physical (DMA) equivalent.
216 static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
218 if (likely((addr >= qe_port->bd_virt)) &&
219 (addr < (qe_port->bd_virt + qe_port->bd_size)))
220 return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
222 /* something nasty happened */
223 printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
229 * Physical to virtual address translation.
231 * Given the physical (DMA) address for a character buffer, this function
232 * returns the virtual equivalent.
234 static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
237 if (likely((addr >= qe_port->bd_dma_addr) &&
238 (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
239 return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
241 /* something nasty happened */
242 printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
248 * Return 1 if the QE is done transmitting all buffers for this port
250 * This function scans each BD in sequence. If we find a BD that is not
251 * ready (READY=1), then we return 0 indicating that the QE is still sending
252 * data. If we reach the last BD (WRAP=1), then we know we've scanned
253 * the entire list, and all BDs are done.
255 static unsigned int qe_uart_tx_empty(struct uart_port *port)
257 struct uart_qe_port *qe_port =
258 container_of(port, struct uart_qe_port, port);
259 struct qe_bd *bdp = qe_port->tx_bd_base;
262 if (in_be16(&bdp->status) & BD_SC_READY)
263 /* This BD is not done, so return "not done" */
266 if (in_be16(&bdp->status) & BD_SC_WRAP)
268 * This BD is done and it's the last one, so return
278 * Set the modem control lines
280 * Although the QE can control the modem control lines (e.g. CTS), we
281 * don't need that support. This function must exist, however, otherwise
282 * the kernel will panic.
284 void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
289 * Get the current modem control line status
291 * Although the QE can control the modem control lines (e.g. CTS), this
292 * driver currently doesn't support that, so we always return Carrier
293 * Detect, Data Set Ready, and Clear To Send.
295 static unsigned int qe_uart_get_mctrl(struct uart_port *port)
297 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
301 * Disable the transmit interrupt.
303 * Although this function is called "stop_tx", it does not actually stop
304 * transmission of data. Instead, it tells the QE to not generate an
305 * interrupt when the UCC is finished sending characters.
307 static void qe_uart_stop_tx(struct uart_port *port)
309 struct uart_qe_port *qe_port =
310 container_of(port, struct uart_qe_port, port);
312 clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
316 * Transmit as many characters to the HW as possible.
318 * This function will attempt to stuff of all the characters from the
319 * kernel's transmit buffer into TX BDs.
321 * A return value of non-zero indicates that it successfully stuffed all
322 * characters from the kernel buffer.
324 * A return value of zero indicates that there are still characters in the
325 * kernel's buffer that have not been transmitted, but there are no more BDs
326 * available. This function should be called again after a BD has been made
329 static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
334 struct uart_port *port = &qe_port->port;
335 struct circ_buf *xmit = &port->state->xmit;
337 bdp = qe_port->rx_cur;
339 /* Handle xon/xoff */
341 /* Pick next descriptor and fill from buffer */
342 bdp = qe_port->tx_cur;
344 p = qe2cpu_addr(bdp->buf, qe_port);
347 out_be16(&bdp->length, 1);
348 setbits16(&bdp->status, BD_SC_READY);
350 if (in_be16(&bdp->status) & BD_SC_WRAP)
351 bdp = qe_port->tx_bd_base;
354 qe_port->tx_cur = bdp;
361 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
362 qe_uart_stop_tx(port);
366 /* Pick next descriptor and fill from buffer */
367 bdp = qe_port->tx_cur;
369 while (!(in_be16(&bdp->status) & BD_SC_READY) &&
370 (xmit->tail != xmit->head)) {
372 p = qe2cpu_addr(bdp->buf, qe_port);
373 while (count < qe_port->tx_fifosize) {
374 *p++ = xmit->buf[xmit->tail];
375 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
378 if (xmit->head == xmit->tail)
382 out_be16(&bdp->length, count);
383 setbits16(&bdp->status, BD_SC_READY);
386 if (in_be16(&bdp->status) & BD_SC_WRAP)
387 bdp = qe_port->tx_bd_base;
391 qe_port->tx_cur = bdp;
393 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
394 uart_write_wakeup(port);
396 if (uart_circ_empty(xmit)) {
397 /* The kernel buffer is empty, so turn off TX interrupts. We
398 don't need to be told when the QE is finished transmitting
400 qe_uart_stop_tx(port);
408 * Start transmitting data
410 * This function will start transmitting any available data, if the port
411 * isn't already transmitting data.
413 static void qe_uart_start_tx(struct uart_port *port)
415 struct uart_qe_port *qe_port =
416 container_of(port, struct uart_qe_port, port);
418 /* If we currently are transmitting, then just return */
419 if (in_be16(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
422 /* Otherwise, pump the port and start transmission */
423 if (qe_uart_tx_pump(qe_port))
424 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
428 * Stop transmitting data
430 static void qe_uart_stop_rx(struct uart_port *port)
432 struct uart_qe_port *qe_port =
433 container_of(port, struct uart_qe_port, port);
435 clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
438 /* Start or stop sending break signal
440 * This function controls the sending of a break signal. If break_state=1,
441 * then we start sending a break signal. If break_state=0, then we stop
442 * sending the break signal.
444 static void qe_uart_break_ctl(struct uart_port *port, int break_state)
446 struct uart_qe_port *qe_port =
447 container_of(port, struct uart_qe_port, port);
450 ucc_slow_stop_tx(qe_port->us_private);
452 ucc_slow_restart_tx(qe_port->us_private);
455 /* ISR helper function for receiving character.
457 * This function is called by the ISR to handling receiving characters
459 static void qe_uart_int_rx(struct uart_qe_port *qe_port)
462 unsigned char ch, *cp;
463 struct uart_port *port = &qe_port->port;
464 struct tty_port *tport = &port->state->port;
469 /* Just loop through the closed BDs and copy the characters into
472 bdp = qe_port->rx_cur;
474 status = in_be16(&bdp->status);
476 /* If this one is empty, then we assume we've read them all */
477 if (status & BD_SC_EMPTY)
480 /* get number of characters, and check space in RX buffer */
481 i = in_be16(&bdp->length);
483 /* If we don't have enough room in RX buffer for the entire BD,
484 * then we try later, which will be the next RX interrupt.
486 if (tty_buffer_request_room(tport, i) < i) {
487 dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
492 cp = qe2cpu_addr(bdp->buf, qe_port);
494 /* loop through the buffer */
501 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
503 if (uart_handle_sysrq_char(port, ch))
507 tty_insert_flip_char(tport, ch, flg);
511 /* This BD is ready to be used again. Clear status. get next */
512 clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
513 BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
514 if (in_be16(&bdp->status) & BD_SC_WRAP)
515 bdp = qe_port->rx_bd_base;
521 /* Write back buffer pointer */
522 qe_port->rx_cur = bdp;
524 /* Activate BH processing */
525 tty_flip_buffer_push(tport);
529 /* Error processing */
533 if (status & BD_SC_BR)
535 if (status & BD_SC_PR)
536 port->icount.parity++;
537 if (status & BD_SC_FR)
538 port->icount.frame++;
539 if (status & BD_SC_OV)
540 port->icount.overrun++;
542 /* Mask out ignored conditions */
543 status &= port->read_status_mask;
545 /* Handle the remaining ones */
546 if (status & BD_SC_BR)
548 else if (status & BD_SC_PR)
550 else if (status & BD_SC_FR)
553 /* Overrun does not affect the current character ! */
554 if (status & BD_SC_OV)
555 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
564 * This interrupt handler is called after a BD is processed.
566 static irqreturn_t qe_uart_int(int irq, void *data)
568 struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
569 struct ucc_slow __iomem *uccp = qe_port->uccp;
572 /* Clear the interrupts */
573 events = in_be16(&uccp->ucce);
574 out_be16(&uccp->ucce, events);
576 if (events & UCC_UART_UCCE_BRKE)
577 uart_handle_break(&qe_port->port);
579 if (events & UCC_UART_UCCE_RX)
580 qe_uart_int_rx(qe_port);
582 if (events & UCC_UART_UCCE_TX)
583 qe_uart_tx_pump(qe_port);
585 return events ? IRQ_HANDLED : IRQ_NONE;
588 /* Initialize buffer descriptors
590 * This function initializes all of the RX and TX buffer descriptors.
592 static void qe_uart_initbd(struct uart_qe_port *qe_port)
598 /* Set the physical address of the host memory buffers in the buffer
599 * descriptors, and the virtual address for us to work with.
601 bd_virt = qe_port->bd_virt;
602 bdp = qe_port->rx_bd_base;
603 qe_port->rx_cur = qe_port->rx_bd_base;
604 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
605 out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
606 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
607 out_be16(&bdp->length, 0);
608 bd_virt += qe_port->rx_fifosize;
613 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
614 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
615 out_be16(&bdp->length, 0);
617 /* Set the physical address of the host memory
618 * buffers in the buffer descriptors, and the
619 * virtual address for us to work with.
621 bd_virt = qe_port->bd_virt +
622 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
623 qe_port->tx_cur = qe_port->tx_bd_base;
624 bdp = qe_port->tx_bd_base;
625 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
626 out_be16(&bdp->status, BD_SC_INTRPT);
627 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
628 out_be16(&bdp->length, 0);
629 bd_virt += qe_port->tx_fifosize;
633 /* Loopback requires the preamble bit to be set on the first TX BD */
635 setbits16(&qe_port->tx_cur->status, BD_SC_P);
638 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
639 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
640 out_be16(&bdp->length, 0);
644 * Initialize a UCC for UART.
646 * This function configures a given UCC to be used as a UART device. Basic
647 * UCC initialization is handled in qe_uart_request_port(). This function
648 * does all the UART-specific stuff.
650 static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
653 struct ucc_slow __iomem *uccp = qe_port->uccp;
654 struct ucc_uart_pram *uccup = qe_port->uccup;
658 /* First, disable TX and RX in the UCC */
659 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
661 /* Program the UCC UART parameter RAM */
662 out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
663 out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
664 out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
665 out_be16(&uccup->maxidl, 0x10);
666 out_be16(&uccup->brkcr, 1);
667 out_be16(&uccup->parec, 0);
668 out_be16(&uccup->frmec, 0);
669 out_be16(&uccup->nosec, 0);
670 out_be16(&uccup->brkec, 0);
671 out_be16(&uccup->uaddr[0], 0);
672 out_be16(&uccup->uaddr[1], 0);
673 out_be16(&uccup->toseq, 0);
674 for (i = 0; i < 8; i++)
675 out_be16(&uccup->cchars[i], 0xC000);
676 out_be16(&uccup->rccm, 0xc0ff);
678 /* Configure the GUMR registers for UART */
680 /* Soft-UART requires a 1X multiplier for TX */
681 clrsetbits_be32(&uccp->gumr_l,
682 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
683 UCC_SLOW_GUMR_L_RDCR_MASK,
684 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
685 UCC_SLOW_GUMR_L_RDCR_16);
687 clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
688 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
690 clrsetbits_be32(&uccp->gumr_l,
691 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
692 UCC_SLOW_GUMR_L_RDCR_MASK,
693 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
694 UCC_SLOW_GUMR_L_RDCR_16);
696 clrsetbits_be32(&uccp->gumr_h,
697 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
698 UCC_SLOW_GUMR_H_RFW);
702 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
703 UCC_SLOW_GUMR_L_DIAG_LOOP);
704 clrsetbits_be32(&uccp->gumr_h,
705 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
706 UCC_SLOW_GUMR_H_CDS);
709 /* Disable rx interrupts and clear all pending events. */
710 out_be16(&uccp->uccm, 0);
711 out_be16(&uccp->ucce, 0xffff);
712 out_be16(&uccp->udsr, 0x7e7e);
714 /* Initialize UPSMR */
715 out_be16(&uccp->upsmr, 0);
718 out_be16(&uccup->supsmr, 0x30);
719 out_be16(&uccup->res92, 0);
720 out_be32(&uccup->rx_state, 0);
721 out_be32(&uccup->rx_cnt, 0);
722 out_8(&uccup->rx_bitmark, 0);
723 out_8(&uccup->rx_length, 10);
724 out_be32(&uccup->dump_ptr, 0x4000);
725 out_8(&uccup->rx_temp_dlst_qe, 0);
726 out_be32(&uccup->rx_frame_rem, 0);
727 out_8(&uccup->rx_frame_rem_size, 0);
728 /* Soft-UART requires TX to be 1X */
729 out_8(&uccup->tx_mode,
730 UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
731 out_be16(&uccup->tx_state, 0);
732 out_8(&uccup->resD4, 0);
733 out_be16(&uccup->resD5, 0);
736 * Enable receive and transmit.
739 /* From the microcode errata:
740 * 1.GUMR_L register, set mode=0010 (QMC).
741 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
742 * 3.Set GUMR_H[19:20] (Transparent mode)
743 * 4.Clear GUMR_H[26] (RFW)
745 * 6.Receiver must use 16x over sampling
747 clrsetbits_be32(&uccp->gumr_l,
748 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
749 UCC_SLOW_GUMR_L_RDCR_MASK,
750 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
751 UCC_SLOW_GUMR_L_RDCR_16);
753 clrsetbits_be32(&uccp->gumr_h,
754 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
755 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
756 UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
759 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
760 UCC_SLOW_GUMR_L_DIAG_LOOP);
761 clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
762 UCC_SLOW_GUMR_H_CDS);
765 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
766 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
767 QE_CR_PROTOCOL_UNSPECIFIED, 0);
769 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
770 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
771 QE_CR_PROTOCOL_UART, 0);
776 * Initialize the port.
778 static int qe_uart_startup(struct uart_port *port)
780 struct uart_qe_port *qe_port =
781 container_of(port, struct uart_qe_port, port);
785 * If we're using Soft-UART mode, then we need to make sure the
786 * firmware has been uploaded first.
788 if (soft_uart && !firmware_loaded) {
789 dev_err(port->dev, "Soft-UART firmware not uploaded\n");
793 qe_uart_initbd(qe_port);
794 qe_uart_init_ucc(qe_port);
796 /* Install interrupt handler. */
797 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
800 dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
805 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
806 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
814 static void qe_uart_shutdown(struct uart_port *port)
816 struct uart_qe_port *qe_port =
817 container_of(port, struct uart_qe_port, port);
818 struct ucc_slow __iomem *uccp = qe_port->uccp;
819 unsigned int timeout = 20;
821 /* Disable RX and TX */
823 /* Wait for all the BDs marked sent */
824 while (!qe_uart_tx_empty(port)) {
826 dev_warn(port->dev, "shutdown timeout\n");
829 set_current_state(TASK_UNINTERRUPTIBLE);
833 if (qe_port->wait_closing) {
834 /* Wait a bit longer */
835 set_current_state(TASK_UNINTERRUPTIBLE);
836 schedule_timeout(qe_port->wait_closing);
840 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
841 clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
843 /* Shut them really down and reinit buffer descriptors */
844 ucc_slow_graceful_stop_tx(qe_port->us_private);
845 qe_uart_initbd(qe_port);
847 free_irq(port->irq, qe_port);
851 * Set the serial port parameters.
853 static void qe_uart_set_termios(struct uart_port *port,
854 struct ktermios *termios, struct ktermios *old)
856 struct uart_qe_port *qe_port =
857 container_of(port, struct uart_qe_port, port);
858 struct ucc_slow __iomem *uccp = qe_port->uccp;
861 u16 upsmr = in_be16(&uccp->upsmr);
862 struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
863 u16 supsmr = in_be16(&uccup->supsmr);
864 u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
866 /* Character length programmed into the mode register is the
867 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
868 * 1 or 2 stop bits, minus 1.
869 * The value 'bits' counts this for us.
873 upsmr &= UCC_UART_UPSMR_CL_MASK;
874 supsmr &= UCC_UART_SUPSMR_CL_MASK;
876 switch (termios->c_cflag & CSIZE) {
878 upsmr |= UCC_UART_UPSMR_CL_5;
879 supsmr |= UCC_UART_SUPSMR_CL_5;
883 upsmr |= UCC_UART_UPSMR_CL_6;
884 supsmr |= UCC_UART_SUPSMR_CL_6;
888 upsmr |= UCC_UART_UPSMR_CL_7;
889 supsmr |= UCC_UART_SUPSMR_CL_7;
892 default: /* case CS8 */
893 upsmr |= UCC_UART_UPSMR_CL_8;
894 supsmr |= UCC_UART_SUPSMR_CL_8;
899 /* If CSTOPB is set, we want two stop bits */
900 if (termios->c_cflag & CSTOPB) {
901 upsmr |= UCC_UART_UPSMR_SL;
902 supsmr |= UCC_UART_SUPSMR_SL;
903 char_length++; /* + SL */
906 if (termios->c_cflag & PARENB) {
907 upsmr |= UCC_UART_UPSMR_PEN;
908 supsmr |= UCC_UART_SUPSMR_PEN;
909 char_length++; /* + PEN */
911 if (!(termios->c_cflag & PARODD)) {
912 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
913 UCC_UART_UPSMR_TPM_MASK);
914 upsmr |= UCC_UART_UPSMR_RPM_EVEN |
915 UCC_UART_UPSMR_TPM_EVEN;
916 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
917 UCC_UART_SUPSMR_TPM_MASK);
918 supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
919 UCC_UART_SUPSMR_TPM_EVEN;
924 * Set up parity check flag
926 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
927 if (termios->c_iflag & INPCK)
928 port->read_status_mask |= BD_SC_FR | BD_SC_PR;
929 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
930 port->read_status_mask |= BD_SC_BR;
933 * Characters to ignore
935 port->ignore_status_mask = 0;
936 if (termios->c_iflag & IGNPAR)
937 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
938 if (termios->c_iflag & IGNBRK) {
939 port->ignore_status_mask |= BD_SC_BR;
941 * If we're ignore parity and break indicators, ignore
942 * overruns too. (For real raw support).
944 if (termios->c_iflag & IGNPAR)
945 port->ignore_status_mask |= BD_SC_OV;
948 * !!! ignore all characters if CREAD is not set
950 if ((termios->c_cflag & CREAD) == 0)
951 port->read_status_mask &= ~BD_SC_EMPTY;
953 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
955 /* Do we really need a spinlock here? */
956 spin_lock_irqsave(&port->lock, flags);
958 /* Update the per-port timeout. */
959 uart_update_timeout(port, termios->c_cflag, baud);
961 out_be16(&uccp->upsmr, upsmr);
963 out_be16(&uccup->supsmr, supsmr);
964 out_8(&uccup->rx_length, char_length);
966 /* Soft-UART requires a 1X multiplier for TX */
967 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
968 qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
970 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
971 qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
974 spin_unlock_irqrestore(&port->lock, flags);
978 * Return a pointer to a string that describes what kind of port this is.
980 static const char *qe_uart_type(struct uart_port *port)
986 * Allocate any memory and I/O resources required by the port.
988 static int qe_uart_request_port(struct uart_port *port)
991 struct uart_qe_port *qe_port =
992 container_of(port, struct uart_qe_port, port);
993 struct ucc_slow_info *us_info = &qe_port->us_info;
994 struct ucc_slow_private *uccs;
995 unsigned int rx_size, tx_size;
997 dma_addr_t bd_dma_addr = 0;
999 ret = ucc_slow_init(us_info, &uccs);
1001 dev_err(port->dev, "could not initialize UCC%u\n",
1006 qe_port->us_private = uccs;
1007 qe_port->uccp = uccs->us_regs;
1008 qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1009 qe_port->rx_bd_base = uccs->rx_bd;
1010 qe_port->tx_bd_base = uccs->tx_bd;
1013 * Allocate the transmit and receive data buffers.
1016 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1017 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1019 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1022 dev_err(port->dev, "could not allocate buffer descriptors\n");
1026 qe_port->bd_virt = bd_virt;
1027 qe_port->bd_dma_addr = bd_dma_addr;
1028 qe_port->bd_size = rx_size + tx_size;
1030 qe_port->rx_buf = bd_virt;
1031 qe_port->tx_buf = qe_port->rx_buf + rx_size;
1037 * Configure the port.
1039 * We say we're a CPM-type port because that's mostly true. Once the device
1040 * is configured, this driver operates almost identically to the CPM serial
1043 static void qe_uart_config_port(struct uart_port *port, int flags)
1045 if (flags & UART_CONFIG_TYPE) {
1046 port->type = PORT_CPM;
1047 qe_uart_request_port(port);
1052 * Release any memory and I/O resources that were allocated in
1053 * qe_uart_request_port().
1055 static void qe_uart_release_port(struct uart_port *port)
1057 struct uart_qe_port *qe_port =
1058 container_of(port, struct uart_qe_port, port);
1059 struct ucc_slow_private *uccs = qe_port->us_private;
1061 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1062 qe_port->bd_dma_addr);
1064 ucc_slow_free(uccs);
1068 * Verify that the data in serial_struct is suitable for this device.
1070 static int qe_uart_verify_port(struct uart_port *port,
1071 struct serial_struct *ser)
1073 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1076 if (ser->irq < 0 || ser->irq >= nr_irqs)
1079 if (ser->baud_base < 9600)
1086 * Details on these functions can be found in Documentation/serial/driver
1088 static struct uart_ops qe_uart_pops = {
1089 .tx_empty = qe_uart_tx_empty,
1090 .set_mctrl = qe_uart_set_mctrl,
1091 .get_mctrl = qe_uart_get_mctrl,
1092 .stop_tx = qe_uart_stop_tx,
1093 .start_tx = qe_uart_start_tx,
1094 .stop_rx = qe_uart_stop_rx,
1095 .break_ctl = qe_uart_break_ctl,
1096 .startup = qe_uart_startup,
1097 .shutdown = qe_uart_shutdown,
1098 .set_termios = qe_uart_set_termios,
1099 .type = qe_uart_type,
1100 .release_port = qe_uart_release_port,
1101 .request_port = qe_uart_request_port,
1102 .config_port = qe_uart_config_port,
1103 .verify_port = qe_uart_verify_port,
1107 * Obtain the SOC model number and revision level
1109 * This function parses the device tree to obtain the SOC model. It then
1110 * reads the SVR register to the revision.
1112 * The device tree stores the SOC model two different ways.
1117 * compatible = "PowerPC,8323";
1118 * device_type = "cpu";
1124 * device_type = "cpu";
1127 * This code first checks the new way, and then the old way.
1129 static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1131 struct device_node *np;
1132 const char *soc_string;
1136 /* Find the CPU node */
1137 np = of_find_node_by_type(NULL, "cpu");
1140 /* Find the compatible property */
1141 soc_string = of_get_property(np, "compatible", NULL);
1143 /* No compatible property, so try the name. */
1144 soc_string = np->name;
1148 /* Extract the SOC number from the "PowerPC," string */
1149 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1152 /* Get the revision from the SVR */
1153 svr = mfspr(SPRN_SVR);
1154 *rev_h = (svr >> 4) & 0xf;
1161 * requst_firmware_nowait() callback function
1163 * This function is called by the kernel when a firmware is made available,
1164 * or if it times out waiting for the firmware.
1166 static void uart_firmware_cont(const struct firmware *fw, void *context)
1168 struct qe_firmware *firmware;
1169 struct device *dev = context;
1173 dev_err(dev, "firmware not found\n");
1177 firmware = (struct qe_firmware *) fw->data;
1179 if (firmware->header.length != fw->size) {
1180 dev_err(dev, "invalid firmware\n");
1184 ret = qe_upload_firmware(firmware);
1186 dev_err(dev, "could not load firmware\n");
1190 firmware_loaded = 1;
1192 release_firmware(fw);
1195 static int ucc_uart_probe(struct platform_device *ofdev)
1197 struct device_node *np = ofdev->dev.of_node;
1198 const unsigned int *iprop; /* Integer OF properties */
1199 const char *sprop; /* String OF properties */
1200 struct uart_qe_port *qe_port = NULL;
1201 struct resource res;
1205 * Determine if we need Soft-UART mode
1207 if (of_find_property(np, "soft-uart", NULL)) {
1208 dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1213 * If we are using Soft-UART, determine if we need to upload the
1217 struct qe_firmware_info *qe_fw_info;
1219 qe_fw_info = qe_get_firmware_info();
1221 /* Check if the firmware has been uploaded. */
1222 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1223 firmware_loaded = 1;
1230 soc = soc_info(&rev_h, &rev_l);
1232 dev_err(&ofdev->dev, "unknown CPU model\n");
1235 sprintf(filename, "/*(DEBLOBBED)*/",
1238 dev_info(&ofdev->dev, "waiting for firmware %s\n",
1242 * We call request_firmware_nowait instead of
1243 * request_firmware so that the driver can load and
1244 * initialize the ports without holding up the rest of
1245 * the kernel. If hotplug support is enabled in the
1246 * kernel, then we use it.
1248 ret = reject_firmware_nowait(THIS_MODULE,
1249 FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1250 GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1252 dev_err(&ofdev->dev,
1253 "could not load firmware %s\n",
1260 qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1262 dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1266 /* Search for IRQ and mapbase */
1267 ret = of_address_to_resource(np, 0, &res);
1269 dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1273 dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1277 qe_port->port.mapbase = res.start;
1279 /* Get the UCC number (device ID) */
1280 /* UCCs are numbered 1-7 */
1281 iprop = of_get_property(np, "cell-index", NULL);
1283 iprop = of_get_property(np, "device-id", NULL);
1285 dev_err(&ofdev->dev, "UCC is unspecified in "
1292 if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1293 dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1297 qe_port->ucc_num = *iprop - 1;
1300 * In the future, we should not require the BRG to be specified in the
1301 * device tree. If no clock-source is specified, then just pick a BRG
1302 * to use. This requires a new QE library function that manages BRG
1306 sprop = of_get_property(np, "rx-clock-name", NULL);
1308 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1313 qe_port->us_info.rx_clock = qe_clock_source(sprop);
1314 if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1315 (qe_port->us_info.rx_clock > QE_BRG16)) {
1316 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1322 /* In internal loopback mode, TX and RX must use the same clock */
1323 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1325 sprop = of_get_property(np, "tx-clock-name", NULL);
1327 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1331 qe_port->us_info.tx_clock = qe_clock_source(sprop);
1333 if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1334 (qe_port->us_info.tx_clock > QE_BRG16)) {
1335 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1340 /* Get the port number, numbered 0-3 */
1341 iprop = of_get_property(np, "port-number", NULL);
1343 dev_err(&ofdev->dev, "missing port-number in device tree\n");
1347 qe_port->port.line = *iprop;
1348 if (qe_port->port.line >= UCC_MAX_UART) {
1349 dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1355 qe_port->port.irq = irq_of_parse_and_map(np, 0);
1356 if (qe_port->port.irq == 0) {
1357 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1358 qe_port->ucc_num + 1);
1364 * Newer device trees have an "fsl,qe" compatible property for the QE
1365 * node, but we still need to support older device trees.
1367 np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1369 np = of_find_node_by_type(NULL, "qe");
1371 dev_err(&ofdev->dev, "could not find 'qe' node\n");
1377 iprop = of_get_property(np, "brg-frequency", NULL);
1379 dev_err(&ofdev->dev,
1380 "missing brg-frequency in device tree\n");
1386 qe_port->port.uartclk = *iprop;
1389 * Older versions of U-Boot do not initialize the brg-frequency
1390 * property, so in this case we assume the BRG frequency is
1391 * half the QE bus frequency.
1393 iprop = of_get_property(np, "bus-frequency", NULL);
1395 dev_err(&ofdev->dev,
1396 "missing QE bus-frequency in device tree\n");
1401 qe_port->port.uartclk = *iprop / 2;
1403 dev_err(&ofdev->dev,
1404 "invalid QE bus-frequency in device tree\n");
1410 spin_lock_init(&qe_port->port.lock);
1412 qe_port->port.dev = &ofdev->dev;
1413 qe_port->port.ops = &qe_uart_pops;
1414 qe_port->port.iotype = UPIO_MEM;
1416 qe_port->tx_nrfifos = TX_NUM_FIFO;
1417 qe_port->tx_fifosize = TX_BUF_SIZE;
1418 qe_port->rx_nrfifos = RX_NUM_FIFO;
1419 qe_port->rx_fifosize = RX_BUF_SIZE;
1421 qe_port->wait_closing = UCC_WAIT_CLOSING;
1422 qe_port->port.fifosize = 512;
1423 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1425 qe_port->us_info.ucc_num = qe_port->ucc_num;
1426 qe_port->us_info.regs = (phys_addr_t) res.start;
1427 qe_port->us_info.irq = qe_port->port.irq;
1429 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1430 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1432 /* Make sure ucc_slow_init() initializes both TX and RX */
1433 qe_port->us_info.init_tx = 1;
1434 qe_port->us_info.init_rx = 1;
1436 /* Add the port to the uart sub-system. This will cause
1437 * qe_uart_config_port() to be called, so the us_info structure must
1440 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1442 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1443 qe_port->port.line);
1447 platform_set_drvdata(ofdev, qe_port);
1449 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1450 qe_port->ucc_num + 1, qe_port->port.line);
1452 /* Display the mknod command for this device */
1453 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1454 qe_port->port.line, SERIAL_QE_MAJOR,
1455 SERIAL_QE_MINOR + qe_port->port.line);
1465 static int ucc_uart_remove(struct platform_device *ofdev)
1467 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1469 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1471 uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1478 static const struct of_device_id ucc_uart_match[] = {
1481 .compatible = "ucc_uart",
1484 .compatible = "fsl,t1040-ucc-uart",
1488 MODULE_DEVICE_TABLE(of, ucc_uart_match);
1490 static struct platform_driver ucc_uart_of_driver = {
1493 .of_match_table = ucc_uart_match,
1495 .probe = ucc_uart_probe,
1496 .remove = ucc_uart_remove,
1499 static int __init ucc_uart_init(void)
1503 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1505 printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1508 ret = uart_register_driver(&ucc_uart_driver);
1510 printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1514 ret = platform_driver_register(&ucc_uart_of_driver);
1517 "ucc-uart: could not register platform driver\n");
1518 uart_unregister_driver(&ucc_uart_driver);
1524 static void __exit ucc_uart_exit(void)
1527 "Freescale QUICC Engine UART device driver unloading\n");
1529 platform_driver_unregister(&ucc_uart_of_driver);
1530 uart_unregister_driver(&ucc_uart_driver);
1533 module_init(ucc_uart_init);
1534 module_exit(ucc_uart_exit);
1536 MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1537 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1538 MODULE_LICENSE("GPL v2");
1539 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);