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 <asm/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);
439 * Enable status change interrupts
441 * We don't support status change interrupts, but we need to define this
442 * function otherwise the kernel will panic.
444 static void qe_uart_enable_ms(struct uart_port *port)
448 /* Start or stop sending break signal
450 * This function controls the sending of a break signal. If break_state=1,
451 * then we start sending a break signal. If break_state=0, then we stop
452 * sending the break signal.
454 static void qe_uart_break_ctl(struct uart_port *port, int break_state)
456 struct uart_qe_port *qe_port =
457 container_of(port, struct uart_qe_port, port);
460 ucc_slow_stop_tx(qe_port->us_private);
462 ucc_slow_restart_tx(qe_port->us_private);
465 /* ISR helper function for receiving character.
467 * This function is called by the ISR to handling receiving characters
469 static void qe_uart_int_rx(struct uart_qe_port *qe_port)
472 unsigned char ch, *cp;
473 struct uart_port *port = &qe_port->port;
474 struct tty_port *tport = &port->state->port;
479 /* Just loop through the closed BDs and copy the characters into
482 bdp = qe_port->rx_cur;
484 status = in_be16(&bdp->status);
486 /* If this one is empty, then we assume we've read them all */
487 if (status & BD_SC_EMPTY)
490 /* get number of characters, and check space in RX buffer */
491 i = in_be16(&bdp->length);
493 /* If we don't have enough room in RX buffer for the entire BD,
494 * then we try later, which will be the next RX interrupt.
496 if (tty_buffer_request_room(tport, i) < i) {
497 dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
502 cp = qe2cpu_addr(bdp->buf, qe_port);
504 /* loop through the buffer */
511 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
513 if (uart_handle_sysrq_char(port, ch))
517 tty_insert_flip_char(tport, ch, flg);
521 /* This BD is ready to be used again. Clear status. get next */
522 clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
523 BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
524 if (in_be16(&bdp->status) & BD_SC_WRAP)
525 bdp = qe_port->rx_bd_base;
531 /* Write back buffer pointer */
532 qe_port->rx_cur = bdp;
534 /* Activate BH processing */
535 tty_flip_buffer_push(tport);
539 /* Error processing */
543 if (status & BD_SC_BR)
545 if (status & BD_SC_PR)
546 port->icount.parity++;
547 if (status & BD_SC_FR)
548 port->icount.frame++;
549 if (status & BD_SC_OV)
550 port->icount.overrun++;
552 /* Mask out ignored conditions */
553 status &= port->read_status_mask;
555 /* Handle the remaining ones */
556 if (status & BD_SC_BR)
558 else if (status & BD_SC_PR)
560 else if (status & BD_SC_FR)
563 /* Overrun does not affect the current character ! */
564 if (status & BD_SC_OV)
565 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
574 * This interrupt handler is called after a BD is processed.
576 static irqreturn_t qe_uart_int(int irq, void *data)
578 struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
579 struct ucc_slow __iomem *uccp = qe_port->uccp;
582 /* Clear the interrupts */
583 events = in_be16(&uccp->ucce);
584 out_be16(&uccp->ucce, events);
586 if (events & UCC_UART_UCCE_BRKE)
587 uart_handle_break(&qe_port->port);
589 if (events & UCC_UART_UCCE_RX)
590 qe_uart_int_rx(qe_port);
592 if (events & UCC_UART_UCCE_TX)
593 qe_uart_tx_pump(qe_port);
595 return events ? IRQ_HANDLED : IRQ_NONE;
598 /* Initialize buffer descriptors
600 * This function initializes all of the RX and TX buffer descriptors.
602 static void qe_uart_initbd(struct uart_qe_port *qe_port)
608 /* Set the physical address of the host memory buffers in the buffer
609 * descriptors, and the virtual address for us to work with.
611 bd_virt = qe_port->bd_virt;
612 bdp = qe_port->rx_bd_base;
613 qe_port->rx_cur = qe_port->rx_bd_base;
614 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
615 out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
616 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
617 out_be16(&bdp->length, 0);
618 bd_virt += qe_port->rx_fifosize;
623 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
624 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
625 out_be16(&bdp->length, 0);
627 /* Set the physical address of the host memory
628 * buffers in the buffer descriptors, and the
629 * virtual address for us to work with.
631 bd_virt = qe_port->bd_virt +
632 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
633 qe_port->tx_cur = qe_port->tx_bd_base;
634 bdp = qe_port->tx_bd_base;
635 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
636 out_be16(&bdp->status, BD_SC_INTRPT);
637 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
638 out_be16(&bdp->length, 0);
639 bd_virt += qe_port->tx_fifosize;
643 /* Loopback requires the preamble bit to be set on the first TX BD */
645 setbits16(&qe_port->tx_cur->status, BD_SC_P);
648 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
649 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
650 out_be16(&bdp->length, 0);
654 * Initialize a UCC for UART.
656 * This function configures a given UCC to be used as a UART device. Basic
657 * UCC initialization is handled in qe_uart_request_port(). This function
658 * does all the UART-specific stuff.
660 static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
663 struct ucc_slow __iomem *uccp = qe_port->uccp;
664 struct ucc_uart_pram *uccup = qe_port->uccup;
668 /* First, disable TX and RX in the UCC */
669 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
671 /* Program the UCC UART parameter RAM */
672 out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
673 out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
674 out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
675 out_be16(&uccup->maxidl, 0x10);
676 out_be16(&uccup->brkcr, 1);
677 out_be16(&uccup->parec, 0);
678 out_be16(&uccup->frmec, 0);
679 out_be16(&uccup->nosec, 0);
680 out_be16(&uccup->brkec, 0);
681 out_be16(&uccup->uaddr[0], 0);
682 out_be16(&uccup->uaddr[1], 0);
683 out_be16(&uccup->toseq, 0);
684 for (i = 0; i < 8; i++)
685 out_be16(&uccup->cchars[i], 0xC000);
686 out_be16(&uccup->rccm, 0xc0ff);
688 /* Configure the GUMR registers for UART */
690 /* Soft-UART requires a 1X multiplier for TX */
691 clrsetbits_be32(&uccp->gumr_l,
692 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
693 UCC_SLOW_GUMR_L_RDCR_MASK,
694 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
695 UCC_SLOW_GUMR_L_RDCR_16);
697 clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
698 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
700 clrsetbits_be32(&uccp->gumr_l,
701 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
702 UCC_SLOW_GUMR_L_RDCR_MASK,
703 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
704 UCC_SLOW_GUMR_L_RDCR_16);
706 clrsetbits_be32(&uccp->gumr_h,
707 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
708 UCC_SLOW_GUMR_H_RFW);
712 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
713 UCC_SLOW_GUMR_L_DIAG_LOOP);
714 clrsetbits_be32(&uccp->gumr_h,
715 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
716 UCC_SLOW_GUMR_H_CDS);
719 /* Disable rx interrupts and clear all pending events. */
720 out_be16(&uccp->uccm, 0);
721 out_be16(&uccp->ucce, 0xffff);
722 out_be16(&uccp->udsr, 0x7e7e);
724 /* Initialize UPSMR */
725 out_be16(&uccp->upsmr, 0);
728 out_be16(&uccup->supsmr, 0x30);
729 out_be16(&uccup->res92, 0);
730 out_be32(&uccup->rx_state, 0);
731 out_be32(&uccup->rx_cnt, 0);
732 out_8(&uccup->rx_bitmark, 0);
733 out_8(&uccup->rx_length, 10);
734 out_be32(&uccup->dump_ptr, 0x4000);
735 out_8(&uccup->rx_temp_dlst_qe, 0);
736 out_be32(&uccup->rx_frame_rem, 0);
737 out_8(&uccup->rx_frame_rem_size, 0);
738 /* Soft-UART requires TX to be 1X */
739 out_8(&uccup->tx_mode,
740 UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
741 out_be16(&uccup->tx_state, 0);
742 out_8(&uccup->resD4, 0);
743 out_be16(&uccup->resD5, 0);
746 * Enable receive and transmit.
749 /* From the microcode errata:
750 * 1.GUMR_L register, set mode=0010 (QMC).
751 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
752 * 3.Set GUMR_H[19:20] (Transparent mode)
753 * 4.Clear GUMR_H[26] (RFW)
755 * 6.Receiver must use 16x over sampling
757 clrsetbits_be32(&uccp->gumr_l,
758 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
759 UCC_SLOW_GUMR_L_RDCR_MASK,
760 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
761 UCC_SLOW_GUMR_L_RDCR_16);
763 clrsetbits_be32(&uccp->gumr_h,
764 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
765 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
766 UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
769 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
770 UCC_SLOW_GUMR_L_DIAG_LOOP);
771 clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
772 UCC_SLOW_GUMR_H_CDS);
775 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
776 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
777 QE_CR_PROTOCOL_UNSPECIFIED, 0);
779 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
780 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
781 QE_CR_PROTOCOL_UART, 0);
786 * Initialize the port.
788 static int qe_uart_startup(struct uart_port *port)
790 struct uart_qe_port *qe_port =
791 container_of(port, struct uart_qe_port, port);
795 * If we're using Soft-UART mode, then we need to make sure the
796 * firmware has been uploaded first.
798 if (soft_uart && !firmware_loaded) {
799 dev_err(port->dev, "Soft-UART firmware not uploaded\n");
803 qe_uart_initbd(qe_port);
804 qe_uart_init_ucc(qe_port);
806 /* Install interrupt handler. */
807 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
810 dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
815 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
816 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
824 static void qe_uart_shutdown(struct uart_port *port)
826 struct uart_qe_port *qe_port =
827 container_of(port, struct uart_qe_port, port);
828 struct ucc_slow __iomem *uccp = qe_port->uccp;
829 unsigned int timeout = 20;
831 /* Disable RX and TX */
833 /* Wait for all the BDs marked sent */
834 while (!qe_uart_tx_empty(port)) {
836 dev_warn(port->dev, "shutdown timeout\n");
839 set_current_state(TASK_UNINTERRUPTIBLE);
843 if (qe_port->wait_closing) {
844 /* Wait a bit longer */
845 set_current_state(TASK_UNINTERRUPTIBLE);
846 schedule_timeout(qe_port->wait_closing);
850 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
851 clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
853 /* Shut them really down and reinit buffer descriptors */
854 ucc_slow_graceful_stop_tx(qe_port->us_private);
855 qe_uart_initbd(qe_port);
857 free_irq(port->irq, qe_port);
861 * Set the serial port parameters.
863 static void qe_uart_set_termios(struct uart_port *port,
864 struct ktermios *termios, struct ktermios *old)
866 struct uart_qe_port *qe_port =
867 container_of(port, struct uart_qe_port, port);
868 struct ucc_slow __iomem *uccp = qe_port->uccp;
871 u16 upsmr = in_be16(&uccp->upsmr);
872 struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
873 u16 supsmr = in_be16(&uccup->supsmr);
874 u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
876 /* Character length programmed into the mode register is the
877 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
878 * 1 or 2 stop bits, minus 1.
879 * The value 'bits' counts this for us.
883 upsmr &= UCC_UART_UPSMR_CL_MASK;
884 supsmr &= UCC_UART_SUPSMR_CL_MASK;
886 switch (termios->c_cflag & CSIZE) {
888 upsmr |= UCC_UART_UPSMR_CL_5;
889 supsmr |= UCC_UART_SUPSMR_CL_5;
893 upsmr |= UCC_UART_UPSMR_CL_6;
894 supsmr |= UCC_UART_SUPSMR_CL_6;
898 upsmr |= UCC_UART_UPSMR_CL_7;
899 supsmr |= UCC_UART_SUPSMR_CL_7;
902 default: /* case CS8 */
903 upsmr |= UCC_UART_UPSMR_CL_8;
904 supsmr |= UCC_UART_SUPSMR_CL_8;
909 /* If CSTOPB is set, we want two stop bits */
910 if (termios->c_cflag & CSTOPB) {
911 upsmr |= UCC_UART_UPSMR_SL;
912 supsmr |= UCC_UART_SUPSMR_SL;
913 char_length++; /* + SL */
916 if (termios->c_cflag & PARENB) {
917 upsmr |= UCC_UART_UPSMR_PEN;
918 supsmr |= UCC_UART_SUPSMR_PEN;
919 char_length++; /* + PEN */
921 if (!(termios->c_cflag & PARODD)) {
922 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
923 UCC_UART_UPSMR_TPM_MASK);
924 upsmr |= UCC_UART_UPSMR_RPM_EVEN |
925 UCC_UART_UPSMR_TPM_EVEN;
926 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
927 UCC_UART_SUPSMR_TPM_MASK);
928 supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
929 UCC_UART_SUPSMR_TPM_EVEN;
934 * Set up parity check flag
936 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
937 if (termios->c_iflag & INPCK)
938 port->read_status_mask |= BD_SC_FR | BD_SC_PR;
939 if (termios->c_iflag & (BRKINT | PARMRK))
940 port->read_status_mask |= BD_SC_BR;
943 * Characters to ignore
945 port->ignore_status_mask = 0;
946 if (termios->c_iflag & IGNPAR)
947 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
948 if (termios->c_iflag & IGNBRK) {
949 port->ignore_status_mask |= BD_SC_BR;
951 * If we're ignore parity and break indicators, ignore
952 * overruns too. (For real raw support).
954 if (termios->c_iflag & IGNPAR)
955 port->ignore_status_mask |= BD_SC_OV;
958 * !!! ignore all characters if CREAD is not set
960 if ((termios->c_cflag & CREAD) == 0)
961 port->read_status_mask &= ~BD_SC_EMPTY;
963 baud = uart_get_baud_rate(port, termios, old, 0, 115200);
965 /* Do we really need a spinlock here? */
966 spin_lock_irqsave(&port->lock, flags);
968 /* Update the per-port timeout. */
969 uart_update_timeout(port, termios->c_cflag, baud);
971 out_be16(&uccp->upsmr, upsmr);
973 out_be16(&uccup->supsmr, supsmr);
974 out_8(&uccup->rx_length, char_length);
976 /* Soft-UART requires a 1X multiplier for TX */
977 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
978 qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
980 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
981 qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
984 spin_unlock_irqrestore(&port->lock, flags);
988 * Return a pointer to a string that describes what kind of port this is.
990 static const char *qe_uart_type(struct uart_port *port)
996 * Allocate any memory and I/O resources required by the port.
998 static int qe_uart_request_port(struct uart_port *port)
1001 struct uart_qe_port *qe_port =
1002 container_of(port, struct uart_qe_port, port);
1003 struct ucc_slow_info *us_info = &qe_port->us_info;
1004 struct ucc_slow_private *uccs;
1005 unsigned int rx_size, tx_size;
1007 dma_addr_t bd_dma_addr = 0;
1009 ret = ucc_slow_init(us_info, &uccs);
1011 dev_err(port->dev, "could not initialize UCC%u\n",
1016 qe_port->us_private = uccs;
1017 qe_port->uccp = uccs->us_regs;
1018 qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1019 qe_port->rx_bd_base = uccs->rx_bd;
1020 qe_port->tx_bd_base = uccs->tx_bd;
1023 * Allocate the transmit and receive data buffers.
1026 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1027 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1029 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1032 dev_err(port->dev, "could not allocate buffer descriptors\n");
1036 qe_port->bd_virt = bd_virt;
1037 qe_port->bd_dma_addr = bd_dma_addr;
1038 qe_port->bd_size = rx_size + tx_size;
1040 qe_port->rx_buf = bd_virt;
1041 qe_port->tx_buf = qe_port->rx_buf + rx_size;
1047 * Configure the port.
1049 * We say we're a CPM-type port because that's mostly true. Once the device
1050 * is configured, this driver operates almost identically to the CPM serial
1053 static void qe_uart_config_port(struct uart_port *port, int flags)
1055 if (flags & UART_CONFIG_TYPE) {
1056 port->type = PORT_CPM;
1057 qe_uart_request_port(port);
1062 * Release any memory and I/O resources that were allocated in
1063 * qe_uart_request_port().
1065 static void qe_uart_release_port(struct uart_port *port)
1067 struct uart_qe_port *qe_port =
1068 container_of(port, struct uart_qe_port, port);
1069 struct ucc_slow_private *uccs = qe_port->us_private;
1071 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1072 qe_port->bd_dma_addr);
1074 ucc_slow_free(uccs);
1078 * Verify that the data in serial_struct is suitable for this device.
1080 static int qe_uart_verify_port(struct uart_port *port,
1081 struct serial_struct *ser)
1083 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1086 if (ser->irq < 0 || ser->irq >= nr_irqs)
1089 if (ser->baud_base < 9600)
1096 * Details on these functions can be found in Documentation/serial/driver
1098 static struct uart_ops qe_uart_pops = {
1099 .tx_empty = qe_uart_tx_empty,
1100 .set_mctrl = qe_uart_set_mctrl,
1101 .get_mctrl = qe_uart_get_mctrl,
1102 .stop_tx = qe_uart_stop_tx,
1103 .start_tx = qe_uart_start_tx,
1104 .stop_rx = qe_uart_stop_rx,
1105 .enable_ms = qe_uart_enable_ms,
1106 .break_ctl = qe_uart_break_ctl,
1107 .startup = qe_uart_startup,
1108 .shutdown = qe_uart_shutdown,
1109 .set_termios = qe_uart_set_termios,
1110 .type = qe_uart_type,
1111 .release_port = qe_uart_release_port,
1112 .request_port = qe_uart_request_port,
1113 .config_port = qe_uart_config_port,
1114 .verify_port = qe_uart_verify_port,
1118 * Obtain the SOC model number and revision level
1120 * This function parses the device tree to obtain the SOC model. It then
1121 * reads the SVR register to the revision.
1123 * The device tree stores the SOC model two different ways.
1128 * compatible = "PowerPC,8323";
1129 * device_type = "cpu";
1135 * device_type = "cpu";
1138 * This code first checks the new way, and then the old way.
1140 static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1142 struct device_node *np;
1143 const char *soc_string;
1147 /* Find the CPU node */
1148 np = of_find_node_by_type(NULL, "cpu");
1151 /* Find the compatible property */
1152 soc_string = of_get_property(np, "compatible", NULL);
1154 /* No compatible property, so try the name. */
1155 soc_string = np->name;
1157 /* Extract the SOC number from the "PowerPC," string */
1158 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1161 /* Get the revision from the SVR */
1162 svr = mfspr(SPRN_SVR);
1163 *rev_h = (svr >> 4) & 0xf;
1170 * requst_firmware_nowait() callback function
1172 * This function is called by the kernel when a firmware is made available,
1173 * or if it times out waiting for the firmware.
1175 static void uart_firmware_cont(const struct firmware *fw, void *context)
1177 struct qe_firmware *firmware;
1178 struct device *dev = context;
1182 dev_err(dev, "firmware not found\n");
1186 firmware = (struct qe_firmware *) fw->data;
1188 if (firmware->header.length != fw->size) {
1189 dev_err(dev, "invalid firmware\n");
1193 ret = qe_upload_firmware(firmware);
1195 dev_err(dev, "could not load firmware\n");
1199 firmware_loaded = 1;
1201 release_firmware(fw);
1204 static int ucc_uart_probe(struct platform_device *ofdev)
1206 struct device_node *np = ofdev->dev.of_node;
1207 const unsigned int *iprop; /* Integer OF properties */
1208 const char *sprop; /* String OF properties */
1209 struct uart_qe_port *qe_port = NULL;
1210 struct resource res;
1214 * Determine if we need Soft-UART mode
1216 if (of_find_property(np, "soft-uart", NULL)) {
1217 dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1222 * If we are using Soft-UART, determine if we need to upload the
1226 struct qe_firmware_info *qe_fw_info;
1228 qe_fw_info = qe_get_firmware_info();
1230 /* Check if the firmware has been uploaded. */
1231 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1232 firmware_loaded = 1;
1239 soc = soc_info(&rev_h, &rev_l);
1241 dev_err(&ofdev->dev, "unknown CPU model\n");
1244 sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1247 dev_info(&ofdev->dev, "waiting for firmware %s\n",
1251 * We call request_firmware_nowait instead of
1252 * request_firmware so that the driver can load and
1253 * initialize the ports without holding up the rest of
1254 * the kernel. If hotplug support is enabled in the
1255 * kernel, then we use it.
1257 ret = request_firmware_nowait(THIS_MODULE,
1258 FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1259 GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1261 dev_err(&ofdev->dev,
1262 "could not load firmware %s\n",
1269 qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1271 dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1275 /* Search for IRQ and mapbase */
1276 ret = of_address_to_resource(np, 0, &res);
1278 dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1282 dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1286 qe_port->port.mapbase = res.start;
1288 /* Get the UCC number (device ID) */
1289 /* UCCs are numbered 1-7 */
1290 iprop = of_get_property(np, "cell-index", NULL);
1292 iprop = of_get_property(np, "device-id", NULL);
1294 dev_err(&ofdev->dev, "UCC is unspecified in "
1301 if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1302 dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1306 qe_port->ucc_num = *iprop - 1;
1309 * In the future, we should not require the BRG to be specified in the
1310 * device tree. If no clock-source is specified, then just pick a BRG
1311 * to use. This requires a new QE library function that manages BRG
1315 sprop = of_get_property(np, "rx-clock-name", NULL);
1317 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1322 qe_port->us_info.rx_clock = qe_clock_source(sprop);
1323 if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1324 (qe_port->us_info.rx_clock > QE_BRG16)) {
1325 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1331 /* In internal loopback mode, TX and RX must use the same clock */
1332 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1334 sprop = of_get_property(np, "tx-clock-name", NULL);
1336 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1340 qe_port->us_info.tx_clock = qe_clock_source(sprop);
1342 if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1343 (qe_port->us_info.tx_clock > QE_BRG16)) {
1344 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1349 /* Get the port number, numbered 0-3 */
1350 iprop = of_get_property(np, "port-number", NULL);
1352 dev_err(&ofdev->dev, "missing port-number in device tree\n");
1356 qe_port->port.line = *iprop;
1357 if (qe_port->port.line >= UCC_MAX_UART) {
1358 dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1364 qe_port->port.irq = irq_of_parse_and_map(np, 0);
1365 if (qe_port->port.irq == 0) {
1366 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1367 qe_port->ucc_num + 1);
1373 * Newer device trees have an "fsl,qe" compatible property for the QE
1374 * node, but we still need to support older device trees.
1376 np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1378 np = of_find_node_by_type(NULL, "qe");
1380 dev_err(&ofdev->dev, "could not find 'qe' node\n");
1386 iprop = of_get_property(np, "brg-frequency", NULL);
1388 dev_err(&ofdev->dev,
1389 "missing brg-frequency in device tree\n");
1395 qe_port->port.uartclk = *iprop;
1398 * Older versions of U-Boot do not initialize the brg-frequency
1399 * property, so in this case we assume the BRG frequency is
1400 * half the QE bus frequency.
1402 iprop = of_get_property(np, "bus-frequency", NULL);
1404 dev_err(&ofdev->dev,
1405 "missing QE bus-frequency in device tree\n");
1410 qe_port->port.uartclk = *iprop / 2;
1412 dev_err(&ofdev->dev,
1413 "invalid QE bus-frequency in device tree\n");
1419 spin_lock_init(&qe_port->port.lock);
1421 qe_port->port.dev = &ofdev->dev;
1422 qe_port->port.ops = &qe_uart_pops;
1423 qe_port->port.iotype = UPIO_MEM;
1425 qe_port->tx_nrfifos = TX_NUM_FIFO;
1426 qe_port->tx_fifosize = TX_BUF_SIZE;
1427 qe_port->rx_nrfifos = RX_NUM_FIFO;
1428 qe_port->rx_fifosize = RX_BUF_SIZE;
1430 qe_port->wait_closing = UCC_WAIT_CLOSING;
1431 qe_port->port.fifosize = 512;
1432 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1434 qe_port->us_info.ucc_num = qe_port->ucc_num;
1435 qe_port->us_info.regs = (phys_addr_t) res.start;
1436 qe_port->us_info.irq = qe_port->port.irq;
1438 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1439 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1441 /* Make sure ucc_slow_init() initializes both TX and RX */
1442 qe_port->us_info.init_tx = 1;
1443 qe_port->us_info.init_rx = 1;
1445 /* Add the port to the uart sub-system. This will cause
1446 * qe_uart_config_port() to be called, so the us_info structure must
1449 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1451 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1452 qe_port->port.line);
1456 platform_set_drvdata(ofdev, qe_port);
1458 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1459 qe_port->ucc_num + 1, qe_port->port.line);
1461 /* Display the mknod command for this device */
1462 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1463 qe_port->port.line, SERIAL_QE_MAJOR,
1464 SERIAL_QE_MINOR + qe_port->port.line);
1474 static int ucc_uart_remove(struct platform_device *ofdev)
1476 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1478 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1480 uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1487 static struct of_device_id ucc_uart_match[] = {
1490 .compatible = "ucc_uart",
1494 MODULE_DEVICE_TABLE(of, ucc_uart_match);
1496 static struct platform_driver ucc_uart_of_driver = {
1499 .owner = THIS_MODULE,
1500 .of_match_table = ucc_uart_match,
1502 .probe = ucc_uart_probe,
1503 .remove = ucc_uart_remove,
1506 static int __init ucc_uart_init(void)
1510 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1512 printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1515 ret = uart_register_driver(&ucc_uart_driver);
1517 printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1521 ret = platform_driver_register(&ucc_uart_of_driver);
1524 "ucc-uart: could not register platform driver\n");
1525 uart_unregister_driver(&ucc_uart_driver);
1531 static void __exit ucc_uart_exit(void)
1534 "Freescale QUICC Engine UART device driver unloading\n");
1536 platform_driver_unregister(&ucc_uart_of_driver);
1537 uart_unregister_driver(&ucc_uart_driver);
1540 module_init(ucc_uart_init);
1541 module_exit(ucc_uart_exit);
1543 MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1544 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1545 MODULE_LICENSE("GPL v2");
1546 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);