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[cris-mirror.git] / drivers / tty / serial / mpc52xx_uart.c
blob3a75ee08d6190b846c5d403d7fb3b5f0b12c4e57
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
5 * FIXME According to the usermanual the status bits in the status register
6 * are only updated when the peripherals access the FIFO and not when the
7 * CPU access them. So since we use this bits to know when we stop writing
8 * and reading, they may not be updated in-time and a race condition may
9 * exists. But I haven't be able to prove this and I don't care. But if
10 * any problem arises, it might worth checking. The TX/RX FIFO Stats
11 * registers should be used in addition.
12 * Update: Actually, they seem updated ... At least the bits we use.
15 * Maintainer : Sylvain Munaut <tnt@246tNt.com>
17 * Some of the code has been inspired/copied from the 2.4 code written
18 * by Dale Farnsworth <dfarnsworth@mvista.com>.
20 * Copyright (C) 2008 Freescale Semiconductor Inc.
21 * John Rigby <jrigby@gmail.com>
22 * Added support for MPC5121
23 * Copyright (C) 2006 Secret Lab Technologies Ltd.
24 * Grant Likely <grant.likely@secretlab.ca>
25 * Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com>
26 * Copyright (C) 2003 MontaVista, Software, Inc.
29 #undef DEBUG
31 #include <linux/device.h>
32 #include <linux/module.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/serial.h>
36 #include <linux/sysrq.h>
37 #include <linux/console.h>
38 #include <linux/delay.h>
39 #include <linux/io.h>
40 #include <linux/of.h>
41 #include <linux/of_platform.h>
42 #include <linux/clk.h>
44 #include <asm/mpc52xx.h>
45 #include <asm/mpc52xx_psc.h>
47 #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
48 #define SUPPORT_SYSRQ
49 #endif
51 #include <linux/serial_core.h>
54 /* We've been assigned a range on the "Low-density serial ports" major */
55 #define SERIAL_PSC_MAJOR 204
56 #define SERIAL_PSC_MINOR 148
59 #define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */
62 static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
63 /* Rem: - We use the read_status_mask as a shadow of
64 * psc->mpc52xx_psc_imr
65 * - It's important that is array is all zero on start as we
66 * use it to know if it's initialized or not ! If it's not sure
67 * it's cleared, then a memset(...,0,...) should be added to
68 * the console_init
71 /* lookup table for matching device nodes to index numbers */
72 static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM];
74 static void mpc52xx_uart_of_enumerate(void);
77 #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
80 /* Forward declaration of the interruption handling routine */
81 static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
82 static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);
84 /* ======================================================================== */
85 /* PSC fifo operations for isolating differences between 52xx and 512x */
86 /* ======================================================================== */
88 struct psc_ops {
89 void (*fifo_init)(struct uart_port *port);
90 int (*raw_rx_rdy)(struct uart_port *port);
91 int (*raw_tx_rdy)(struct uart_port *port);
92 int (*rx_rdy)(struct uart_port *port);
93 int (*tx_rdy)(struct uart_port *port);
94 int (*tx_empty)(struct uart_port *port);
95 void (*stop_rx)(struct uart_port *port);
96 void (*start_tx)(struct uart_port *port);
97 void (*stop_tx)(struct uart_port *port);
98 void (*rx_clr_irq)(struct uart_port *port);
99 void (*tx_clr_irq)(struct uart_port *port);
100 void (*write_char)(struct uart_port *port, unsigned char c);
101 unsigned char (*read_char)(struct uart_port *port);
102 void (*cw_disable_ints)(struct uart_port *port);
103 void (*cw_restore_ints)(struct uart_port *port);
104 unsigned int (*set_baudrate)(struct uart_port *port,
105 struct ktermios *new,
106 struct ktermios *old);
107 int (*clock_alloc)(struct uart_port *port);
108 void (*clock_relse)(struct uart_port *port);
109 int (*clock)(struct uart_port *port, int enable);
110 int (*fifoc_init)(void);
111 void (*fifoc_uninit)(void);
112 void (*get_irq)(struct uart_port *, struct device_node *);
113 irqreturn_t (*handle_irq)(struct uart_port *port);
114 u16 (*get_status)(struct uart_port *port);
115 u8 (*get_ipcr)(struct uart_port *port);
116 void (*command)(struct uart_port *port, u8 cmd);
117 void (*set_mode)(struct uart_port *port, u8 mr1, u8 mr2);
118 void (*set_rts)(struct uart_port *port, int state);
119 void (*enable_ms)(struct uart_port *port);
120 void (*set_sicr)(struct uart_port *port, u32 val);
121 void (*set_imr)(struct uart_port *port, u16 val);
122 u8 (*get_mr1)(struct uart_port *port);
125 /* setting the prescaler and divisor reg is common for all chips */
126 static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc,
127 u16 prescaler, unsigned int divisor)
129 /* select prescaler */
130 out_be16(&psc->mpc52xx_psc_clock_select, prescaler);
131 out_8(&psc->ctur, divisor >> 8);
132 out_8(&psc->ctlr, divisor & 0xff);
135 static u16 mpc52xx_psc_get_status(struct uart_port *port)
137 return in_be16(&PSC(port)->mpc52xx_psc_status);
140 static u8 mpc52xx_psc_get_ipcr(struct uart_port *port)
142 return in_8(&PSC(port)->mpc52xx_psc_ipcr);
145 static void mpc52xx_psc_command(struct uart_port *port, u8 cmd)
147 out_8(&PSC(port)->command, cmd);
150 static void mpc52xx_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
152 out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
153 out_8(&PSC(port)->mode, mr1);
154 out_8(&PSC(port)->mode, mr2);
157 static void mpc52xx_psc_set_rts(struct uart_port *port, int state)
159 if (state)
160 out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS);
161 else
162 out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS);
165 static void mpc52xx_psc_enable_ms(struct uart_port *port)
167 struct mpc52xx_psc __iomem *psc = PSC(port);
169 /* clear D_*-bits by reading them */
170 in_8(&psc->mpc52xx_psc_ipcr);
171 /* enable CTS and DCD as IPC interrupts */
172 out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
174 port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
175 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
178 static void mpc52xx_psc_set_sicr(struct uart_port *port, u32 val)
180 out_be32(&PSC(port)->sicr, val);
183 static void mpc52xx_psc_set_imr(struct uart_port *port, u16 val)
185 out_be16(&PSC(port)->mpc52xx_psc_imr, val);
188 static u8 mpc52xx_psc_get_mr1(struct uart_port *port)
190 out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
191 return in_8(&PSC(port)->mode);
194 #ifdef CONFIG_PPC_MPC52xx
195 #define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
196 static void mpc52xx_psc_fifo_init(struct uart_port *port)
198 struct mpc52xx_psc __iomem *psc = PSC(port);
199 struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
201 out_8(&fifo->rfcntl, 0x00);
202 out_be16(&fifo->rfalarm, 0x1ff);
203 out_8(&fifo->tfcntl, 0x07);
204 out_be16(&fifo->tfalarm, 0x80);
206 port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
207 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
210 static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
212 return in_be16(&PSC(port)->mpc52xx_psc_status)
213 & MPC52xx_PSC_SR_RXRDY;
216 static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
218 return in_be16(&PSC(port)->mpc52xx_psc_status)
219 & MPC52xx_PSC_SR_TXRDY;
223 static int mpc52xx_psc_rx_rdy(struct uart_port *port)
225 return in_be16(&PSC(port)->mpc52xx_psc_isr)
226 & port->read_status_mask
227 & MPC52xx_PSC_IMR_RXRDY;
230 static int mpc52xx_psc_tx_rdy(struct uart_port *port)
232 return in_be16(&PSC(port)->mpc52xx_psc_isr)
233 & port->read_status_mask
234 & MPC52xx_PSC_IMR_TXRDY;
237 static int mpc52xx_psc_tx_empty(struct uart_port *port)
239 u16 sts = in_be16(&PSC(port)->mpc52xx_psc_status);
241 return (sts & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
244 static void mpc52xx_psc_start_tx(struct uart_port *port)
246 port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
247 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
250 static void mpc52xx_psc_stop_tx(struct uart_port *port)
252 port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
253 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
256 static void mpc52xx_psc_stop_rx(struct uart_port *port)
258 port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
259 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
262 static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
266 static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
270 static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
272 out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
275 static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
277 return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
280 static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
282 out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
285 static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
287 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
290 static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
291 struct ktermios *new,
292 struct ktermios *old)
294 unsigned int baud;
295 unsigned int divisor;
297 /* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
298 baud = uart_get_baud_rate(port, new, old,
299 port->uartclk / (32 * 0xffff) + 1,
300 port->uartclk / 32);
301 divisor = (port->uartclk + 16 * baud) / (32 * baud);
303 /* enable the /32 prescaler and set the divisor */
304 mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
305 return baud;
308 static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
309 struct ktermios *new,
310 struct ktermios *old)
312 unsigned int baud;
313 unsigned int divisor;
314 u16 prescaler;
316 /* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
317 * ipb freq */
318 baud = uart_get_baud_rate(port, new, old,
319 port->uartclk / (32 * 0xffff) + 1,
320 port->uartclk / 4);
321 divisor = (port->uartclk + 2 * baud) / (4 * baud);
323 /* select the proper prescaler and set the divisor
324 * prefer high prescaler for more tolerance on low baudrates */
325 if (divisor > 0xffff || baud <= 115200) {
326 divisor = (divisor + 4) / 8;
327 prescaler = 0xdd00; /* /32 */
328 } else
329 prescaler = 0xff00; /* /4 */
330 mpc52xx_set_divisor(PSC(port), prescaler, divisor);
331 return baud;
334 static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
336 port->irqflags = 0;
337 port->irq = irq_of_parse_and_map(np, 0);
340 /* 52xx specific interrupt handler. The caller holds the port lock */
341 static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
343 return mpc5xxx_uart_process_int(port);
346 static const struct psc_ops mpc52xx_psc_ops = {
347 .fifo_init = mpc52xx_psc_fifo_init,
348 .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
349 .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
350 .rx_rdy = mpc52xx_psc_rx_rdy,
351 .tx_rdy = mpc52xx_psc_tx_rdy,
352 .tx_empty = mpc52xx_psc_tx_empty,
353 .stop_rx = mpc52xx_psc_stop_rx,
354 .start_tx = mpc52xx_psc_start_tx,
355 .stop_tx = mpc52xx_psc_stop_tx,
356 .rx_clr_irq = mpc52xx_psc_rx_clr_irq,
357 .tx_clr_irq = mpc52xx_psc_tx_clr_irq,
358 .write_char = mpc52xx_psc_write_char,
359 .read_char = mpc52xx_psc_read_char,
360 .cw_disable_ints = mpc52xx_psc_cw_disable_ints,
361 .cw_restore_ints = mpc52xx_psc_cw_restore_ints,
362 .set_baudrate = mpc5200_psc_set_baudrate,
363 .get_irq = mpc52xx_psc_get_irq,
364 .handle_irq = mpc52xx_psc_handle_irq,
365 .get_status = mpc52xx_psc_get_status,
366 .get_ipcr = mpc52xx_psc_get_ipcr,
367 .command = mpc52xx_psc_command,
368 .set_mode = mpc52xx_psc_set_mode,
369 .set_rts = mpc52xx_psc_set_rts,
370 .enable_ms = mpc52xx_psc_enable_ms,
371 .set_sicr = mpc52xx_psc_set_sicr,
372 .set_imr = mpc52xx_psc_set_imr,
373 .get_mr1 = mpc52xx_psc_get_mr1,
376 static const struct psc_ops mpc5200b_psc_ops = {
377 .fifo_init = mpc52xx_psc_fifo_init,
378 .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
379 .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
380 .rx_rdy = mpc52xx_psc_rx_rdy,
381 .tx_rdy = mpc52xx_psc_tx_rdy,
382 .tx_empty = mpc52xx_psc_tx_empty,
383 .stop_rx = mpc52xx_psc_stop_rx,
384 .start_tx = mpc52xx_psc_start_tx,
385 .stop_tx = mpc52xx_psc_stop_tx,
386 .rx_clr_irq = mpc52xx_psc_rx_clr_irq,
387 .tx_clr_irq = mpc52xx_psc_tx_clr_irq,
388 .write_char = mpc52xx_psc_write_char,
389 .read_char = mpc52xx_psc_read_char,
390 .cw_disable_ints = mpc52xx_psc_cw_disable_ints,
391 .cw_restore_ints = mpc52xx_psc_cw_restore_ints,
392 .set_baudrate = mpc5200b_psc_set_baudrate,
393 .get_irq = mpc52xx_psc_get_irq,
394 .handle_irq = mpc52xx_psc_handle_irq,
395 .get_status = mpc52xx_psc_get_status,
396 .get_ipcr = mpc52xx_psc_get_ipcr,
397 .command = mpc52xx_psc_command,
398 .set_mode = mpc52xx_psc_set_mode,
399 .set_rts = mpc52xx_psc_set_rts,
400 .enable_ms = mpc52xx_psc_enable_ms,
401 .set_sicr = mpc52xx_psc_set_sicr,
402 .set_imr = mpc52xx_psc_set_imr,
403 .get_mr1 = mpc52xx_psc_get_mr1,
406 #endif /* CONFIG_PPC_MPC52xx */
408 #ifdef CONFIG_PPC_MPC512x
409 #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
411 /* PSC FIFO Controller for mpc512x */
412 struct psc_fifoc {
413 u32 fifoc_cmd;
414 u32 fifoc_int;
415 u32 fifoc_dma;
416 u32 fifoc_axe;
417 u32 fifoc_debug;
420 static struct psc_fifoc __iomem *psc_fifoc;
421 static unsigned int psc_fifoc_irq;
422 static struct clk *psc_fifoc_clk;
424 static void mpc512x_psc_fifo_init(struct uart_port *port)
426 /* /32 prescaler */
427 out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
429 out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
430 out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
431 out_be32(&FIFO_512x(port)->txalarm, 1);
432 out_be32(&FIFO_512x(port)->tximr, 0);
434 out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
435 out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
436 out_be32(&FIFO_512x(port)->rxalarm, 1);
437 out_be32(&FIFO_512x(port)->rximr, 0);
439 out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
440 out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
443 static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
445 return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
448 static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
450 return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
453 static int mpc512x_psc_rx_rdy(struct uart_port *port)
455 return in_be32(&FIFO_512x(port)->rxsr)
456 & in_be32(&FIFO_512x(port)->rximr)
457 & MPC512x_PSC_FIFO_ALARM;
460 static int mpc512x_psc_tx_rdy(struct uart_port *port)
462 return in_be32(&FIFO_512x(port)->txsr)
463 & in_be32(&FIFO_512x(port)->tximr)
464 & MPC512x_PSC_FIFO_ALARM;
467 static int mpc512x_psc_tx_empty(struct uart_port *port)
469 return in_be32(&FIFO_512x(port)->txsr)
470 & MPC512x_PSC_FIFO_EMPTY;
473 static void mpc512x_psc_stop_rx(struct uart_port *port)
475 unsigned long rx_fifo_imr;
477 rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
478 rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
479 out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
482 static void mpc512x_psc_start_tx(struct uart_port *port)
484 unsigned long tx_fifo_imr;
486 tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
487 tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
488 out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
491 static void mpc512x_psc_stop_tx(struct uart_port *port)
493 unsigned long tx_fifo_imr;
495 tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
496 tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
497 out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
500 static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
502 out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
505 static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
507 out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
510 static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
512 out_8(&FIFO_512x(port)->txdata_8, c);
515 static unsigned char mpc512x_psc_read_char(struct uart_port *port)
517 return in_8(&FIFO_512x(port)->rxdata_8);
520 static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
522 port->read_status_mask =
523 in_be32(&FIFO_512x(port)->tximr) << 16 |
524 in_be32(&FIFO_512x(port)->rximr);
525 out_be32(&FIFO_512x(port)->tximr, 0);
526 out_be32(&FIFO_512x(port)->rximr, 0);
529 static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
531 out_be32(&FIFO_512x(port)->tximr,
532 (port->read_status_mask >> 16) & 0x7f);
533 out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
536 static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
537 struct ktermios *new,
538 struct ktermios *old)
540 unsigned int baud;
541 unsigned int divisor;
544 * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
545 * pg. 30-10 that the chip supports a /32 and a /10 prescaler.
546 * Furthermore, it states that "After reset, the prescaler by 10
547 * for the UART mode is selected", but the reset register value is
548 * 0x0000 which means a /32 prescaler. This is wrong.
550 * In reality using /32 prescaler doesn't work, as it is not supported!
551 * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
552 * Chapter 4.1 PSC in UART Mode.
553 * Calculate with a /16 prescaler here.
556 /* uartclk contains the ips freq */
557 baud = uart_get_baud_rate(port, new, old,
558 port->uartclk / (16 * 0xffff) + 1,
559 port->uartclk / 16);
560 divisor = (port->uartclk + 8 * baud) / (16 * baud);
562 /* enable the /16 prescaler and set the divisor */
563 mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
564 return baud;
567 /* Init PSC FIFO Controller */
568 static int __init mpc512x_psc_fifoc_init(void)
570 int err;
571 struct device_node *np;
572 struct clk *clk;
574 /* default error code, potentially overwritten by clock calls */
575 err = -ENODEV;
577 np = of_find_compatible_node(NULL, NULL,
578 "fsl,mpc5121-psc-fifo");
579 if (!np) {
580 pr_err("%s: Can't find FIFOC node\n", __func__);
581 goto out_err;
584 clk = of_clk_get(np, 0);
585 if (IS_ERR(clk)) {
586 /* backwards compat with device trees that lack clock specs */
587 clk = clk_get_sys(np->name, "ipg");
589 if (IS_ERR(clk)) {
590 pr_err("%s: Can't lookup FIFO clock\n", __func__);
591 err = PTR_ERR(clk);
592 goto out_ofnode_put;
594 if (clk_prepare_enable(clk)) {
595 pr_err("%s: Can't enable FIFO clock\n", __func__);
596 clk_put(clk);
597 goto out_ofnode_put;
599 psc_fifoc_clk = clk;
601 psc_fifoc = of_iomap(np, 0);
602 if (!psc_fifoc) {
603 pr_err("%s: Can't map FIFOC\n", __func__);
604 goto out_clk_disable;
607 psc_fifoc_irq = irq_of_parse_and_map(np, 0);
608 if (psc_fifoc_irq == 0) {
609 pr_err("%s: Can't get FIFOC irq\n", __func__);
610 goto out_unmap;
613 of_node_put(np);
614 return 0;
616 out_unmap:
617 iounmap(psc_fifoc);
618 out_clk_disable:
619 clk_disable_unprepare(psc_fifoc_clk);
620 clk_put(psc_fifoc_clk);
621 out_ofnode_put:
622 of_node_put(np);
623 out_err:
624 return err;
627 static void __exit mpc512x_psc_fifoc_uninit(void)
629 iounmap(psc_fifoc);
631 /* disable the clock, errors are not fatal */
632 if (psc_fifoc_clk) {
633 clk_disable_unprepare(psc_fifoc_clk);
634 clk_put(psc_fifoc_clk);
635 psc_fifoc_clk = NULL;
639 /* 512x specific interrupt handler. The caller holds the port lock */
640 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
642 unsigned long fifoc_int;
643 int psc_num;
645 /* Read pending PSC FIFOC interrupts */
646 fifoc_int = in_be32(&psc_fifoc->fifoc_int);
648 /* Check if it is an interrupt for this port */
649 psc_num = (port->mapbase & 0xf00) >> 8;
650 if (test_bit(psc_num, &fifoc_int) ||
651 test_bit(psc_num + 16, &fifoc_int))
652 return mpc5xxx_uart_process_int(port);
654 return IRQ_NONE;
657 static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
658 static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
660 /* called from within the .request_port() callback (allocation) */
661 static int mpc512x_psc_alloc_clock(struct uart_port *port)
663 int psc_num;
664 struct clk *clk;
665 int err;
667 psc_num = (port->mapbase & 0xf00) >> 8;
669 clk = devm_clk_get(port->dev, "mclk");
670 if (IS_ERR(clk)) {
671 dev_err(port->dev, "Failed to get MCLK!\n");
672 err = PTR_ERR(clk);
673 goto out_err;
675 err = clk_prepare_enable(clk);
676 if (err) {
677 dev_err(port->dev, "Failed to enable MCLK!\n");
678 goto out_err;
680 psc_mclk_clk[psc_num] = clk;
682 clk = devm_clk_get(port->dev, "ipg");
683 if (IS_ERR(clk)) {
684 dev_err(port->dev, "Failed to get IPG clock!\n");
685 err = PTR_ERR(clk);
686 goto out_err;
688 err = clk_prepare_enable(clk);
689 if (err) {
690 dev_err(port->dev, "Failed to enable IPG clock!\n");
691 goto out_err;
693 psc_ipg_clk[psc_num] = clk;
695 return 0;
697 out_err:
698 if (psc_mclk_clk[psc_num]) {
699 clk_disable_unprepare(psc_mclk_clk[psc_num]);
700 psc_mclk_clk[psc_num] = NULL;
702 if (psc_ipg_clk[psc_num]) {
703 clk_disable_unprepare(psc_ipg_clk[psc_num]);
704 psc_ipg_clk[psc_num] = NULL;
706 return err;
709 /* called from within the .release_port() callback (release) */
710 static void mpc512x_psc_relse_clock(struct uart_port *port)
712 int psc_num;
713 struct clk *clk;
715 psc_num = (port->mapbase & 0xf00) >> 8;
716 clk = psc_mclk_clk[psc_num];
717 if (clk) {
718 clk_disable_unprepare(clk);
719 psc_mclk_clk[psc_num] = NULL;
721 if (psc_ipg_clk[psc_num]) {
722 clk_disable_unprepare(psc_ipg_clk[psc_num]);
723 psc_ipg_clk[psc_num] = NULL;
727 /* implementation of the .clock() callback (enable/disable) */
728 static int mpc512x_psc_endis_clock(struct uart_port *port, int enable)
730 int psc_num;
731 struct clk *psc_clk;
732 int ret;
734 if (uart_console(port))
735 return 0;
737 psc_num = (port->mapbase & 0xf00) >> 8;
738 psc_clk = psc_mclk_clk[psc_num];
739 if (!psc_clk) {
740 dev_err(port->dev, "Failed to get PSC clock entry!\n");
741 return -ENODEV;
744 dev_dbg(port->dev, "mclk %sable\n", enable ? "en" : "dis");
745 if (enable) {
746 ret = clk_enable(psc_clk);
747 if (ret)
748 dev_err(port->dev, "Failed to enable MCLK!\n");
749 return ret;
750 } else {
751 clk_disable(psc_clk);
752 return 0;
756 static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
758 port->irqflags = IRQF_SHARED;
759 port->irq = psc_fifoc_irq;
761 #endif
763 #ifdef CONFIG_PPC_MPC512x
765 #define PSC_5125(port) ((struct mpc5125_psc __iomem *)((port)->membase))
766 #define FIFO_5125(port) ((struct mpc512x_psc_fifo __iomem *)(PSC_5125(port)+1))
768 static void mpc5125_psc_fifo_init(struct uart_port *port)
770 /* /32 prescaler */
771 out_8(&PSC_5125(port)->mpc52xx_psc_clock_select, 0xdd);
773 out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
774 out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
775 out_be32(&FIFO_5125(port)->txalarm, 1);
776 out_be32(&FIFO_5125(port)->tximr, 0);
778 out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
779 out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
780 out_be32(&FIFO_5125(port)->rxalarm, 1);
781 out_be32(&FIFO_5125(port)->rximr, 0);
783 out_be32(&FIFO_5125(port)->tximr, MPC512x_PSC_FIFO_ALARM);
784 out_be32(&FIFO_5125(port)->rximr, MPC512x_PSC_FIFO_ALARM);
787 static int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
789 return !(in_be32(&FIFO_5125(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
792 static int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
794 return !(in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_FULL);
797 static int mpc5125_psc_rx_rdy(struct uart_port *port)
799 return in_be32(&FIFO_5125(port)->rxsr) &
800 in_be32(&FIFO_5125(port)->rximr) & MPC512x_PSC_FIFO_ALARM;
803 static int mpc5125_psc_tx_rdy(struct uart_port *port)
805 return in_be32(&FIFO_5125(port)->txsr) &
806 in_be32(&FIFO_5125(port)->tximr) & MPC512x_PSC_FIFO_ALARM;
809 static int mpc5125_psc_tx_empty(struct uart_port *port)
811 return in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_EMPTY;
814 static void mpc5125_psc_stop_rx(struct uart_port *port)
816 unsigned long rx_fifo_imr;
818 rx_fifo_imr = in_be32(&FIFO_5125(port)->rximr);
819 rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
820 out_be32(&FIFO_5125(port)->rximr, rx_fifo_imr);
823 static void mpc5125_psc_start_tx(struct uart_port *port)
825 unsigned long tx_fifo_imr;
827 tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
828 tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
829 out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
832 static void mpc5125_psc_stop_tx(struct uart_port *port)
834 unsigned long tx_fifo_imr;
836 tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
837 tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
838 out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
841 static void mpc5125_psc_rx_clr_irq(struct uart_port *port)
843 out_be32(&FIFO_5125(port)->rxisr, in_be32(&FIFO_5125(port)->rxisr));
846 static void mpc5125_psc_tx_clr_irq(struct uart_port *port)
848 out_be32(&FIFO_5125(port)->txisr, in_be32(&FIFO_5125(port)->txisr));
851 static void mpc5125_psc_write_char(struct uart_port *port, unsigned char c)
853 out_8(&FIFO_5125(port)->txdata_8, c);
856 static unsigned char mpc5125_psc_read_char(struct uart_port *port)
858 return in_8(&FIFO_5125(port)->rxdata_8);
861 static void mpc5125_psc_cw_disable_ints(struct uart_port *port)
863 port->read_status_mask =
864 in_be32(&FIFO_5125(port)->tximr) << 16 |
865 in_be32(&FIFO_5125(port)->rximr);
866 out_be32(&FIFO_5125(port)->tximr, 0);
867 out_be32(&FIFO_5125(port)->rximr, 0);
870 static void mpc5125_psc_cw_restore_ints(struct uart_port *port)
872 out_be32(&FIFO_5125(port)->tximr,
873 (port->read_status_mask >> 16) & 0x7f);
874 out_be32(&FIFO_5125(port)->rximr, port->read_status_mask & 0x7f);
877 static inline void mpc5125_set_divisor(struct mpc5125_psc __iomem *psc,
878 u8 prescaler, unsigned int divisor)
880 /* select prescaler */
881 out_8(&psc->mpc52xx_psc_clock_select, prescaler);
882 out_8(&psc->ctur, divisor >> 8);
883 out_8(&psc->ctlr, divisor & 0xff);
886 static unsigned int mpc5125_psc_set_baudrate(struct uart_port *port,
887 struct ktermios *new,
888 struct ktermios *old)
890 unsigned int baud;
891 unsigned int divisor;
894 * Calculate with a /16 prescaler here.
897 /* uartclk contains the ips freq */
898 baud = uart_get_baud_rate(port, new, old,
899 port->uartclk / (16 * 0xffff) + 1,
900 port->uartclk / 16);
901 divisor = (port->uartclk + 8 * baud) / (16 * baud);
903 /* enable the /16 prescaler and set the divisor */
904 mpc5125_set_divisor(PSC_5125(port), 0xdd, divisor);
905 return baud;
909 * MPC5125 have compatible PSC FIFO Controller.
910 * Special init not needed.
912 static u16 mpc5125_psc_get_status(struct uart_port *port)
914 return in_be16(&PSC_5125(port)->mpc52xx_psc_status);
917 static u8 mpc5125_psc_get_ipcr(struct uart_port *port)
919 return in_8(&PSC_5125(port)->mpc52xx_psc_ipcr);
922 static void mpc5125_psc_command(struct uart_port *port, u8 cmd)
924 out_8(&PSC_5125(port)->command, cmd);
927 static void mpc5125_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
929 out_8(&PSC_5125(port)->mr1, mr1);
930 out_8(&PSC_5125(port)->mr2, mr2);
933 static void mpc5125_psc_set_rts(struct uart_port *port, int state)
935 if (state & TIOCM_RTS)
936 out_8(&PSC_5125(port)->op1, MPC52xx_PSC_OP_RTS);
937 else
938 out_8(&PSC_5125(port)->op0, MPC52xx_PSC_OP_RTS);
941 static void mpc5125_psc_enable_ms(struct uart_port *port)
943 struct mpc5125_psc __iomem *psc = PSC_5125(port);
945 /* clear D_*-bits by reading them */
946 in_8(&psc->mpc52xx_psc_ipcr);
947 /* enable CTS and DCD as IPC interrupts */
948 out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
950 port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
951 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
954 static void mpc5125_psc_set_sicr(struct uart_port *port, u32 val)
956 out_be32(&PSC_5125(port)->sicr, val);
959 static void mpc5125_psc_set_imr(struct uart_port *port, u16 val)
961 out_be16(&PSC_5125(port)->mpc52xx_psc_imr, val);
964 static u8 mpc5125_psc_get_mr1(struct uart_port *port)
966 return in_8(&PSC_5125(port)->mr1);
969 static const struct psc_ops mpc5125_psc_ops = {
970 .fifo_init = mpc5125_psc_fifo_init,
971 .raw_rx_rdy = mpc5125_psc_raw_rx_rdy,
972 .raw_tx_rdy = mpc5125_psc_raw_tx_rdy,
973 .rx_rdy = mpc5125_psc_rx_rdy,
974 .tx_rdy = mpc5125_psc_tx_rdy,
975 .tx_empty = mpc5125_psc_tx_empty,
976 .stop_rx = mpc5125_psc_stop_rx,
977 .start_tx = mpc5125_psc_start_tx,
978 .stop_tx = mpc5125_psc_stop_tx,
979 .rx_clr_irq = mpc5125_psc_rx_clr_irq,
980 .tx_clr_irq = mpc5125_psc_tx_clr_irq,
981 .write_char = mpc5125_psc_write_char,
982 .read_char = mpc5125_psc_read_char,
983 .cw_disable_ints = mpc5125_psc_cw_disable_ints,
984 .cw_restore_ints = mpc5125_psc_cw_restore_ints,
985 .set_baudrate = mpc5125_psc_set_baudrate,
986 .clock_alloc = mpc512x_psc_alloc_clock,
987 .clock_relse = mpc512x_psc_relse_clock,
988 .clock = mpc512x_psc_endis_clock,
989 .fifoc_init = mpc512x_psc_fifoc_init,
990 .fifoc_uninit = mpc512x_psc_fifoc_uninit,
991 .get_irq = mpc512x_psc_get_irq,
992 .handle_irq = mpc512x_psc_handle_irq,
993 .get_status = mpc5125_psc_get_status,
994 .get_ipcr = mpc5125_psc_get_ipcr,
995 .command = mpc5125_psc_command,
996 .set_mode = mpc5125_psc_set_mode,
997 .set_rts = mpc5125_psc_set_rts,
998 .enable_ms = mpc5125_psc_enable_ms,
999 .set_sicr = mpc5125_psc_set_sicr,
1000 .set_imr = mpc5125_psc_set_imr,
1001 .get_mr1 = mpc5125_psc_get_mr1,
1004 static const struct psc_ops mpc512x_psc_ops = {
1005 .fifo_init = mpc512x_psc_fifo_init,
1006 .raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
1007 .raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
1008 .rx_rdy = mpc512x_psc_rx_rdy,
1009 .tx_rdy = mpc512x_psc_tx_rdy,
1010 .tx_empty = mpc512x_psc_tx_empty,
1011 .stop_rx = mpc512x_psc_stop_rx,
1012 .start_tx = mpc512x_psc_start_tx,
1013 .stop_tx = mpc512x_psc_stop_tx,
1014 .rx_clr_irq = mpc512x_psc_rx_clr_irq,
1015 .tx_clr_irq = mpc512x_psc_tx_clr_irq,
1016 .write_char = mpc512x_psc_write_char,
1017 .read_char = mpc512x_psc_read_char,
1018 .cw_disable_ints = mpc512x_psc_cw_disable_ints,
1019 .cw_restore_ints = mpc512x_psc_cw_restore_ints,
1020 .set_baudrate = mpc512x_psc_set_baudrate,
1021 .clock_alloc = mpc512x_psc_alloc_clock,
1022 .clock_relse = mpc512x_psc_relse_clock,
1023 .clock = mpc512x_psc_endis_clock,
1024 .fifoc_init = mpc512x_psc_fifoc_init,
1025 .fifoc_uninit = mpc512x_psc_fifoc_uninit,
1026 .get_irq = mpc512x_psc_get_irq,
1027 .handle_irq = mpc512x_psc_handle_irq,
1028 .get_status = mpc52xx_psc_get_status,
1029 .get_ipcr = mpc52xx_psc_get_ipcr,
1030 .command = mpc52xx_psc_command,
1031 .set_mode = mpc52xx_psc_set_mode,
1032 .set_rts = mpc52xx_psc_set_rts,
1033 .enable_ms = mpc52xx_psc_enable_ms,
1034 .set_sicr = mpc52xx_psc_set_sicr,
1035 .set_imr = mpc52xx_psc_set_imr,
1036 .get_mr1 = mpc52xx_psc_get_mr1,
1038 #endif /* CONFIG_PPC_MPC512x */
1041 static const struct psc_ops *psc_ops;
1043 /* ======================================================================== */
1044 /* UART operations */
1045 /* ======================================================================== */
1047 static unsigned int
1048 mpc52xx_uart_tx_empty(struct uart_port *port)
1050 return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
1053 static void
1054 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1056 psc_ops->set_rts(port, mctrl & TIOCM_RTS);
1059 static unsigned int
1060 mpc52xx_uart_get_mctrl(struct uart_port *port)
1062 unsigned int ret = TIOCM_DSR;
1063 u8 status = psc_ops->get_ipcr(port);
1065 if (!(status & MPC52xx_PSC_CTS))
1066 ret |= TIOCM_CTS;
1067 if (!(status & MPC52xx_PSC_DCD))
1068 ret |= TIOCM_CAR;
1070 return ret;
1073 static void
1074 mpc52xx_uart_stop_tx(struct uart_port *port)
1076 /* port->lock taken by caller */
1077 psc_ops->stop_tx(port);
1080 static void
1081 mpc52xx_uart_start_tx(struct uart_port *port)
1083 /* port->lock taken by caller */
1084 psc_ops->start_tx(port);
1087 static void
1088 mpc52xx_uart_stop_rx(struct uart_port *port)
1090 /* port->lock taken by caller */
1091 psc_ops->stop_rx(port);
1094 static void
1095 mpc52xx_uart_enable_ms(struct uart_port *port)
1097 psc_ops->enable_ms(port);
1100 static void
1101 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
1103 unsigned long flags;
1104 spin_lock_irqsave(&port->lock, flags);
1106 if (ctl == -1)
1107 psc_ops->command(port, MPC52xx_PSC_START_BRK);
1108 else
1109 psc_ops->command(port, MPC52xx_PSC_STOP_BRK);
1111 spin_unlock_irqrestore(&port->lock, flags);
1114 static int
1115 mpc52xx_uart_startup(struct uart_port *port)
1117 int ret;
1119 if (psc_ops->clock) {
1120 ret = psc_ops->clock(port, 1);
1121 if (ret)
1122 return ret;
1125 /* Request IRQ */
1126 ret = request_irq(port->irq, mpc52xx_uart_int,
1127 port->irqflags, "mpc52xx_psc_uart", port);
1128 if (ret)
1129 return ret;
1131 /* Reset/activate the port, clear and enable interrupts */
1132 psc_ops->command(port, MPC52xx_PSC_RST_RX);
1133 psc_ops->command(port, MPC52xx_PSC_RST_TX);
1136 * According to Freescale's support the RST_TX command can produce a
1137 * spike on the TX pin. So they recommend to delay "for one character".
1138 * One millisecond should be enough for everyone.
1140 msleep(1);
1142 psc_ops->set_sicr(port, 0); /* UART mode DCD ignored */
1144 psc_ops->fifo_init(port);
1146 psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1147 psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1149 return 0;
1152 static void
1153 mpc52xx_uart_shutdown(struct uart_port *port)
1155 /* Shut down the port. Leave TX active if on a console port */
1156 psc_ops->command(port, MPC52xx_PSC_RST_RX);
1157 if (!uart_console(port))
1158 psc_ops->command(port, MPC52xx_PSC_RST_TX);
1160 port->read_status_mask = 0;
1161 psc_ops->set_imr(port, port->read_status_mask);
1163 if (psc_ops->clock)
1164 psc_ops->clock(port, 0);
1166 /* Disable interrupt */
1167 psc_ops->cw_disable_ints(port);
1169 /* Release interrupt */
1170 free_irq(port->irq, port);
1173 static void
1174 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
1175 struct ktermios *old)
1177 unsigned long flags;
1178 unsigned char mr1, mr2;
1179 unsigned int j;
1180 unsigned int baud;
1182 /* Prepare what we're gonna write */
1183 mr1 = 0;
1185 switch (new->c_cflag & CSIZE) {
1186 case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS;
1187 break;
1188 case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS;
1189 break;
1190 case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS;
1191 break;
1192 case CS8:
1193 default: mr1 |= MPC52xx_PSC_MODE_8_BITS;
1196 if (new->c_cflag & PARENB) {
1197 if (new->c_cflag & CMSPAR)
1198 mr1 |= MPC52xx_PSC_MODE_PARFORCE;
1200 /* With CMSPAR, PARODD also means high parity (same as termios) */
1201 mr1 |= (new->c_cflag & PARODD) ?
1202 MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
1203 } else {
1204 mr1 |= MPC52xx_PSC_MODE_PARNONE;
1207 mr2 = 0;
1209 if (new->c_cflag & CSTOPB)
1210 mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
1211 else
1212 mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
1213 MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
1214 MPC52xx_PSC_MODE_ONE_STOP;
1216 if (new->c_cflag & CRTSCTS) {
1217 mr1 |= MPC52xx_PSC_MODE_RXRTS;
1218 mr2 |= MPC52xx_PSC_MODE_TXCTS;
1221 /* Get the lock */
1222 spin_lock_irqsave(&port->lock, flags);
1224 /* Do our best to flush TX & RX, so we don't lose anything */
1225 /* But we don't wait indefinitely ! */
1226 j = 5000000; /* Maximum wait */
1227 /* FIXME Can't receive chars since set_termios might be called at early
1228 * boot for the console, all stuff is not yet ready to receive at that
1229 * time and that just makes the kernel oops */
1230 /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
1231 while (!mpc52xx_uart_tx_empty(port) && --j)
1232 udelay(1);
1234 if (!j)
1235 printk(KERN_ERR "mpc52xx_uart.c: "
1236 "Unable to flush RX & TX fifos in-time in set_termios."
1237 "Some chars may have been lost.\n");
1239 /* Reset the TX & RX */
1240 psc_ops->command(port, MPC52xx_PSC_RST_RX);
1241 psc_ops->command(port, MPC52xx_PSC_RST_TX);
1243 /* Send new mode settings */
1244 psc_ops->set_mode(port, mr1, mr2);
1245 baud = psc_ops->set_baudrate(port, new, old);
1247 /* Update the per-port timeout */
1248 uart_update_timeout(port, new->c_cflag, baud);
1250 if (UART_ENABLE_MS(port, new->c_cflag))
1251 mpc52xx_uart_enable_ms(port);
1253 /* Reenable TX & RX */
1254 psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1255 psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1257 /* We're all set, release the lock */
1258 spin_unlock_irqrestore(&port->lock, flags);
1261 static const char *
1262 mpc52xx_uart_type(struct uart_port *port)
1265 * We keep using PORT_MPC52xx for historic reasons although it applies
1266 * for MPC512x, too, but print "MPC5xxx" to not irritate users
1268 return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
1271 static void
1272 mpc52xx_uart_release_port(struct uart_port *port)
1274 if (psc_ops->clock_relse)
1275 psc_ops->clock_relse(port);
1277 /* remapped by us ? */
1278 if (port->flags & UPF_IOREMAP) {
1279 iounmap(port->membase);
1280 port->membase = NULL;
1283 release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1286 static int
1287 mpc52xx_uart_request_port(struct uart_port *port)
1289 int err;
1291 if (port->flags & UPF_IOREMAP) /* Need to remap ? */
1292 port->membase = ioremap(port->mapbase,
1293 sizeof(struct mpc52xx_psc));
1295 if (!port->membase)
1296 return -EINVAL;
1298 err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
1299 "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
1301 if (err)
1302 goto out_membase;
1304 if (psc_ops->clock_alloc) {
1305 err = psc_ops->clock_alloc(port);
1306 if (err)
1307 goto out_mapregion;
1310 return 0;
1312 out_mapregion:
1313 release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1314 out_membase:
1315 if (port->flags & UPF_IOREMAP) {
1316 iounmap(port->membase);
1317 port->membase = NULL;
1319 return err;
1322 static void
1323 mpc52xx_uart_config_port(struct uart_port *port, int flags)
1325 if ((flags & UART_CONFIG_TYPE)
1326 && (mpc52xx_uart_request_port(port) == 0))
1327 port->type = PORT_MPC52xx;
1330 static int
1331 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
1333 if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
1334 return -EINVAL;
1336 if ((ser->irq != port->irq) ||
1337 (ser->io_type != UPIO_MEM) ||
1338 (ser->baud_base != port->uartclk) ||
1339 (ser->iomem_base != (void *)port->mapbase) ||
1340 (ser->hub6 != 0))
1341 return -EINVAL;
1343 return 0;
1347 static const struct uart_ops mpc52xx_uart_ops = {
1348 .tx_empty = mpc52xx_uart_tx_empty,
1349 .set_mctrl = mpc52xx_uart_set_mctrl,
1350 .get_mctrl = mpc52xx_uart_get_mctrl,
1351 .stop_tx = mpc52xx_uart_stop_tx,
1352 .start_tx = mpc52xx_uart_start_tx,
1353 .stop_rx = mpc52xx_uart_stop_rx,
1354 .enable_ms = mpc52xx_uart_enable_ms,
1355 .break_ctl = mpc52xx_uart_break_ctl,
1356 .startup = mpc52xx_uart_startup,
1357 .shutdown = mpc52xx_uart_shutdown,
1358 .set_termios = mpc52xx_uart_set_termios,
1359 /* .pm = mpc52xx_uart_pm, Not supported yet */
1360 .type = mpc52xx_uart_type,
1361 .release_port = mpc52xx_uart_release_port,
1362 .request_port = mpc52xx_uart_request_port,
1363 .config_port = mpc52xx_uart_config_port,
1364 .verify_port = mpc52xx_uart_verify_port
1368 /* ======================================================================== */
1369 /* Interrupt handling */
1370 /* ======================================================================== */
1372 static inline int
1373 mpc52xx_uart_int_rx_chars(struct uart_port *port)
1375 struct tty_port *tport = &port->state->port;
1376 unsigned char ch, flag;
1377 unsigned short status;
1379 /* While we can read, do so ! */
1380 while (psc_ops->raw_rx_rdy(port)) {
1381 /* Get the char */
1382 ch = psc_ops->read_char(port);
1384 /* Handle sysreq char */
1385 #ifdef SUPPORT_SYSRQ
1386 if (uart_handle_sysrq_char(port, ch)) {
1387 port->sysrq = 0;
1388 continue;
1390 #endif
1392 /* Store it */
1394 flag = TTY_NORMAL;
1395 port->icount.rx++;
1397 status = psc_ops->get_status(port);
1399 if (status & (MPC52xx_PSC_SR_PE |
1400 MPC52xx_PSC_SR_FE |
1401 MPC52xx_PSC_SR_RB)) {
1403 if (status & MPC52xx_PSC_SR_RB) {
1404 flag = TTY_BREAK;
1405 uart_handle_break(port);
1406 port->icount.brk++;
1407 } else if (status & MPC52xx_PSC_SR_PE) {
1408 flag = TTY_PARITY;
1409 port->icount.parity++;
1411 else if (status & MPC52xx_PSC_SR_FE) {
1412 flag = TTY_FRAME;
1413 port->icount.frame++;
1416 /* Clear error condition */
1417 psc_ops->command(port, MPC52xx_PSC_RST_ERR_STAT);
1420 tty_insert_flip_char(tport, ch, flag);
1421 if (status & MPC52xx_PSC_SR_OE) {
1423 * Overrun is special, since it's
1424 * reported immediately, and doesn't
1425 * affect the current character
1427 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1428 port->icount.overrun++;
1432 spin_unlock(&port->lock);
1433 tty_flip_buffer_push(tport);
1434 spin_lock(&port->lock);
1436 return psc_ops->raw_rx_rdy(port);
1439 static inline int
1440 mpc52xx_uart_int_tx_chars(struct uart_port *port)
1442 struct circ_buf *xmit = &port->state->xmit;
1444 /* Process out of band chars */
1445 if (port->x_char) {
1446 psc_ops->write_char(port, port->x_char);
1447 port->icount.tx++;
1448 port->x_char = 0;
1449 return 1;
1452 /* Nothing to do ? */
1453 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
1454 mpc52xx_uart_stop_tx(port);
1455 return 0;
1458 /* Send chars */
1459 while (psc_ops->raw_tx_rdy(port)) {
1460 psc_ops->write_char(port, xmit->buf[xmit->tail]);
1461 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1462 port->icount.tx++;
1463 if (uart_circ_empty(xmit))
1464 break;
1467 /* Wake up */
1468 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1469 uart_write_wakeup(port);
1471 /* Maybe we're done after all */
1472 if (uart_circ_empty(xmit)) {
1473 mpc52xx_uart_stop_tx(port);
1474 return 0;
1477 return 1;
1480 static irqreturn_t
1481 mpc5xxx_uart_process_int(struct uart_port *port)
1483 unsigned long pass = ISR_PASS_LIMIT;
1484 unsigned int keepgoing;
1485 u8 status;
1487 /* While we have stuff to do, we continue */
1488 do {
1489 /* If we don't find anything to do, we stop */
1490 keepgoing = 0;
1492 psc_ops->rx_clr_irq(port);
1493 if (psc_ops->rx_rdy(port))
1494 keepgoing |= mpc52xx_uart_int_rx_chars(port);
1496 psc_ops->tx_clr_irq(port);
1497 if (psc_ops->tx_rdy(port))
1498 keepgoing |= mpc52xx_uart_int_tx_chars(port);
1500 status = psc_ops->get_ipcr(port);
1501 if (status & MPC52xx_PSC_D_DCD)
1502 uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
1504 if (status & MPC52xx_PSC_D_CTS)
1505 uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
1507 /* Limit number of iteration */
1508 if (!(--pass))
1509 keepgoing = 0;
1511 } while (keepgoing);
1513 return IRQ_HANDLED;
1516 static irqreturn_t
1517 mpc52xx_uart_int(int irq, void *dev_id)
1519 struct uart_port *port = dev_id;
1520 irqreturn_t ret;
1522 spin_lock(&port->lock);
1524 ret = psc_ops->handle_irq(port);
1526 spin_unlock(&port->lock);
1528 return ret;
1531 /* ======================================================================== */
1532 /* Console ( if applicable ) */
1533 /* ======================================================================== */
1535 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
1537 static void __init
1538 mpc52xx_console_get_options(struct uart_port *port,
1539 int *baud, int *parity, int *bits, int *flow)
1541 unsigned char mr1;
1543 pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
1545 /* Read the mode registers */
1546 mr1 = psc_ops->get_mr1(port);
1548 /* CT{U,L}R are write-only ! */
1549 *baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1551 /* Parse them */
1552 switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
1553 case MPC52xx_PSC_MODE_5_BITS:
1554 *bits = 5;
1555 break;
1556 case MPC52xx_PSC_MODE_6_BITS:
1557 *bits = 6;
1558 break;
1559 case MPC52xx_PSC_MODE_7_BITS:
1560 *bits = 7;
1561 break;
1562 case MPC52xx_PSC_MODE_8_BITS:
1563 default:
1564 *bits = 8;
1567 if (mr1 & MPC52xx_PSC_MODE_PARNONE)
1568 *parity = 'n';
1569 else
1570 *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
1573 static void
1574 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
1576 struct uart_port *port = &mpc52xx_uart_ports[co->index];
1577 unsigned int i, j;
1579 /* Disable interrupts */
1580 psc_ops->cw_disable_ints(port);
1582 /* Wait the TX buffer to be empty */
1583 j = 5000000; /* Maximum wait */
1584 while (!mpc52xx_uart_tx_empty(port) && --j)
1585 udelay(1);
1587 /* Write all the chars */
1588 for (i = 0; i < count; i++, s++) {
1589 /* Line return handling */
1590 if (*s == '\n')
1591 psc_ops->write_char(port, '\r');
1593 /* Send the char */
1594 psc_ops->write_char(port, *s);
1596 /* Wait the TX buffer to be empty */
1597 j = 20000; /* Maximum wait */
1598 while (!mpc52xx_uart_tx_empty(port) && --j)
1599 udelay(1);
1602 /* Restore interrupt state */
1603 psc_ops->cw_restore_ints(port);
1607 static int __init
1608 mpc52xx_console_setup(struct console *co, char *options)
1610 struct uart_port *port = &mpc52xx_uart_ports[co->index];
1611 struct device_node *np = mpc52xx_uart_nodes[co->index];
1612 unsigned int uartclk;
1613 struct resource res;
1614 int ret;
1616 int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1617 int bits = 8;
1618 int parity = 'n';
1619 int flow = 'n';
1621 pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
1622 co, co->index, options);
1624 if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
1625 pr_debug("PSC%x out of range\n", co->index);
1626 return -EINVAL;
1629 if (!np) {
1630 pr_debug("PSC%x not found in device tree\n", co->index);
1631 return -EINVAL;
1634 pr_debug("Console on ttyPSC%x is %pOF\n",
1635 co->index, mpc52xx_uart_nodes[co->index]);
1637 /* Fetch register locations */
1638 ret = of_address_to_resource(np, 0, &res);
1639 if (ret) {
1640 pr_debug("Could not get resources for PSC%x\n", co->index);
1641 return ret;
1644 uartclk = mpc5xxx_get_bus_frequency(np);
1645 if (uartclk == 0) {
1646 pr_debug("Could not find uart clock frequency!\n");
1647 return -EINVAL;
1650 /* Basic port init. Needed since we use some uart_??? func before
1651 * real init for early access */
1652 spin_lock_init(&port->lock);
1653 port->uartclk = uartclk;
1654 port->ops = &mpc52xx_uart_ops;
1655 port->mapbase = res.start;
1656 port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
1657 port->irq = irq_of_parse_and_map(np, 0);
1659 if (port->membase == NULL)
1660 return -EINVAL;
1662 pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
1663 (void *)port->mapbase, port->membase,
1664 port->irq, port->uartclk);
1666 /* Setup the port parameters accoding to options */
1667 if (options)
1668 uart_parse_options(options, &baud, &parity, &bits, &flow);
1669 else
1670 mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
1672 pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
1673 baud, bits, parity, flow);
1675 return uart_set_options(port, co, baud, parity, bits, flow);
1679 static struct uart_driver mpc52xx_uart_driver;
1681 static struct console mpc52xx_console = {
1682 .name = "ttyPSC",
1683 .write = mpc52xx_console_write,
1684 .device = uart_console_device,
1685 .setup = mpc52xx_console_setup,
1686 .flags = CON_PRINTBUFFER,
1687 .index = -1, /* Specified on the cmdline (e.g. console=ttyPSC0) */
1688 .data = &mpc52xx_uart_driver,
1692 static int __init
1693 mpc52xx_console_init(void)
1695 mpc52xx_uart_of_enumerate();
1696 register_console(&mpc52xx_console);
1697 return 0;
1700 console_initcall(mpc52xx_console_init);
1702 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
1703 #else
1704 #define MPC52xx_PSC_CONSOLE NULL
1705 #endif
1708 /* ======================================================================== */
1709 /* UART Driver */
1710 /* ======================================================================== */
1712 static struct uart_driver mpc52xx_uart_driver = {
1713 .driver_name = "mpc52xx_psc_uart",
1714 .dev_name = "ttyPSC",
1715 .major = SERIAL_PSC_MAJOR,
1716 .minor = SERIAL_PSC_MINOR,
1717 .nr = MPC52xx_PSC_MAXNUM,
1718 .cons = MPC52xx_PSC_CONSOLE,
1721 /* ======================================================================== */
1722 /* OF Platform Driver */
1723 /* ======================================================================== */
1725 static const struct of_device_id mpc52xx_uart_of_match[] = {
1726 #ifdef CONFIG_PPC_MPC52xx
1727 { .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
1728 { .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1729 /* binding used by old lite5200 device trees: */
1730 { .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1731 /* binding used by efika: */
1732 { .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
1733 #endif
1734 #ifdef CONFIG_PPC_MPC512x
1735 { .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
1736 { .compatible = "fsl,mpc5125-psc-uart", .data = &mpc5125_psc_ops, },
1737 #endif
1741 static int mpc52xx_uart_of_probe(struct platform_device *op)
1743 int idx = -1;
1744 unsigned int uartclk;
1745 struct uart_port *port = NULL;
1746 struct resource res;
1747 int ret;
1749 /* Check validity & presence */
1750 for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
1751 if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
1752 break;
1753 if (idx >= MPC52xx_PSC_MAXNUM)
1754 return -EINVAL;
1755 pr_debug("Found %pOF assigned to ttyPSC%x\n",
1756 mpc52xx_uart_nodes[idx], idx);
1758 /* set the uart clock to the input clock of the psc, the different
1759 * prescalers are taken into account in the set_baudrate() methods
1760 * of the respective chip */
1761 uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
1762 if (uartclk == 0) {
1763 dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
1764 return -EINVAL;
1767 /* Init the port structure */
1768 port = &mpc52xx_uart_ports[idx];
1770 spin_lock_init(&port->lock);
1771 port->uartclk = uartclk;
1772 port->fifosize = 512;
1773 port->iotype = UPIO_MEM;
1774 port->flags = UPF_BOOT_AUTOCONF |
1775 (uart_console(port) ? 0 : UPF_IOREMAP);
1776 port->line = idx;
1777 port->ops = &mpc52xx_uart_ops;
1778 port->dev = &op->dev;
1780 /* Search for IRQ and mapbase */
1781 ret = of_address_to_resource(op->dev.of_node, 0, &res);
1782 if (ret)
1783 return ret;
1785 port->mapbase = res.start;
1786 if (!port->mapbase) {
1787 dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
1788 return -EINVAL;
1791 psc_ops->get_irq(port, op->dev.of_node);
1792 if (port->irq == 0) {
1793 dev_dbg(&op->dev, "Could not get irq\n");
1794 return -EINVAL;
1797 dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
1798 (void *)port->mapbase, port->irq, port->uartclk);
1800 /* Add the port to the uart sub-system */
1801 ret = uart_add_one_port(&mpc52xx_uart_driver, port);
1802 if (ret)
1803 return ret;
1805 platform_set_drvdata(op, (void *)port);
1806 return 0;
1809 static int
1810 mpc52xx_uart_of_remove(struct platform_device *op)
1812 struct uart_port *port = platform_get_drvdata(op);
1814 if (port)
1815 uart_remove_one_port(&mpc52xx_uart_driver, port);
1817 return 0;
1820 #ifdef CONFIG_PM
1821 static int
1822 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
1824 struct uart_port *port = platform_get_drvdata(op);
1826 if (port)
1827 uart_suspend_port(&mpc52xx_uart_driver, port);
1829 return 0;
1832 static int
1833 mpc52xx_uart_of_resume(struct platform_device *op)
1835 struct uart_port *port = platform_get_drvdata(op);
1837 if (port)
1838 uart_resume_port(&mpc52xx_uart_driver, port);
1840 return 0;
1842 #endif
1844 static void
1845 mpc52xx_uart_of_assign(struct device_node *np)
1847 int i;
1849 /* Find the first free PSC number */
1850 for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1851 if (mpc52xx_uart_nodes[i] == NULL) {
1852 of_node_get(np);
1853 mpc52xx_uart_nodes[i] = np;
1854 return;
1859 static void
1860 mpc52xx_uart_of_enumerate(void)
1862 static int enum_done;
1863 struct device_node *np;
1864 const struct of_device_id *match;
1865 int i;
1867 if (enum_done)
1868 return;
1870 /* Assign index to each PSC in device tree */
1871 for_each_matching_node(np, mpc52xx_uart_of_match) {
1872 match = of_match_node(mpc52xx_uart_of_match, np);
1873 psc_ops = match->data;
1874 mpc52xx_uart_of_assign(np);
1877 enum_done = 1;
1879 for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1880 if (mpc52xx_uart_nodes[i])
1881 pr_debug("%pOF assigned to ttyPSC%x\n",
1882 mpc52xx_uart_nodes[i], i);
1886 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
1888 static struct platform_driver mpc52xx_uart_of_driver = {
1889 .probe = mpc52xx_uart_of_probe,
1890 .remove = mpc52xx_uart_of_remove,
1891 #ifdef CONFIG_PM
1892 .suspend = mpc52xx_uart_of_suspend,
1893 .resume = mpc52xx_uart_of_resume,
1894 #endif
1895 .driver = {
1896 .name = "mpc52xx-psc-uart",
1897 .of_match_table = mpc52xx_uart_of_match,
1902 /* ======================================================================== */
1903 /* Module */
1904 /* ======================================================================== */
1906 static int __init
1907 mpc52xx_uart_init(void)
1909 int ret;
1911 printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
1913 ret = uart_register_driver(&mpc52xx_uart_driver);
1914 if (ret) {
1915 printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
1916 __FILE__, ret);
1917 return ret;
1920 mpc52xx_uart_of_enumerate();
1923 * Map the PSC FIFO Controller and init if on MPC512x.
1925 if (psc_ops && psc_ops->fifoc_init) {
1926 ret = psc_ops->fifoc_init();
1927 if (ret)
1928 goto err_init;
1931 ret = platform_driver_register(&mpc52xx_uart_of_driver);
1932 if (ret) {
1933 printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
1934 __FILE__, ret);
1935 goto err_reg;
1938 return 0;
1939 err_reg:
1940 if (psc_ops && psc_ops->fifoc_uninit)
1941 psc_ops->fifoc_uninit();
1942 err_init:
1943 uart_unregister_driver(&mpc52xx_uart_driver);
1944 return ret;
1947 static void __exit
1948 mpc52xx_uart_exit(void)
1950 if (psc_ops->fifoc_uninit)
1951 psc_ops->fifoc_uninit();
1953 platform_driver_unregister(&mpc52xx_uart_of_driver);
1954 uart_unregister_driver(&mpc52xx_uart_driver);
1958 module_init(mpc52xx_uart_init);
1959 module_exit(mpc52xx_uart_exit);
1961 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
1962 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
1963 MODULE_LICENSE("GPL");