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serial: omap: Support debug UART
[people/ms/u-boot.git] / drivers / serial / ns16550.c
1 /*
2 * COM1 NS16550 support
3 * originally from linux source (arch/powerpc/boot/ns16550.c)
4 * modified to use CONFIG_SYS_ISA_MEM and new defines
5 */
6
7 #include <common.h>
8 #include <clk.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <fdtdec.h>
12 #include <ns16550.h>
13 #include <serial.h>
14 #include <watchdog.h>
15 #include <linux/types.h>
16 #include <asm/io.h>
17
18 DECLARE_GLOBAL_DATA_PTR;
19
20 #define UART_LCRVAL UART_LCR_8N1 /* 8 data, 1 stop, no parity */
21 #define UART_MCRVAL (UART_MCR_DTR | \
22 UART_MCR_RTS) /* RTS/DTR */
23
24 #ifndef CONFIG_DM_SERIAL
25 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
26 #define serial_out(x, y) outb(x, (ulong)y)
27 #define serial_in(y) inb((ulong)y)
28 #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE > 0)
29 #define serial_out(x, y) out_be32(y, x)
30 #define serial_in(y) in_be32(y)
31 #elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE < 0)
32 #define serial_out(x, y) out_le32(y, x)
33 #define serial_in(y) in_le32(y)
34 #else
35 #define serial_out(x, y) writeb(x, y)
36 #define serial_in(y) readb(y)
37 #endif
38 #endif /* !CONFIG_DM_SERIAL */
39
40 #if defined(CONFIG_SOC_KEYSTONE)
41 #define UART_REG_VAL_PWREMU_MGMT_UART_DISABLE 0
42 #define UART_REG_VAL_PWREMU_MGMT_UART_ENABLE ((1 << 14) | (1 << 13) | (1 << 0))
43 #undef UART_MCRVAL
44 #ifdef CONFIG_SERIAL_HW_FLOW_CONTROL
45 #define UART_MCRVAL (UART_MCR_RTS | UART_MCR_AFE)
46 #else
47 #define UART_MCRVAL (UART_MCR_RTS)
48 #endif
49 #endif
50
51 #ifndef CONFIG_SYS_NS16550_IER
52 #define CONFIG_SYS_NS16550_IER 0x00
53 #endif /* CONFIG_SYS_NS16550_IER */
54
55 static inline void serial_out_shift(void *addr, int shift, int value)
56 {
57 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
58 outb(value, (ulong)addr);
59 #elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
60 out_le32(addr, value);
61 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
62 out_be32(addr, value);
63 #elif defined(CONFIG_SYS_NS16550_MEM32)
64 writel(value, addr);
65 #elif defined(CONFIG_SYS_BIG_ENDIAN)
66 writeb(value, addr + (1 << shift) - 1);
67 #else
68 writeb(value, addr);
69 #endif
70 }
71
72 static inline int serial_in_shift(void *addr, int shift)
73 {
74 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
75 return inb((ulong)addr);
76 #elif defined(CONFIG_SYS_NS16550_MEM32) && !defined(CONFIG_SYS_BIG_ENDIAN)
77 return in_le32(addr);
78 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
79 return in_be32(addr);
80 #elif defined(CONFIG_SYS_NS16550_MEM32)
81 return readl(addr);
82 #elif defined(CONFIG_SYS_BIG_ENDIAN)
83 return readb(addr + (1 << shift) - 1);
84 #else
85 return readb(addr);
86 #endif
87 }
88
89 #ifdef CONFIG_DM_SERIAL
90
91 #ifndef CONFIG_SYS_NS16550_CLK
92 #define CONFIG_SYS_NS16550_CLK 0
93 #endif
94
95 static void ns16550_writeb(NS16550_t port, int offset, int value)
96 {
97 struct ns16550_platdata *plat = port->plat;
98 unsigned char *addr;
99
100 offset *= 1 << plat->reg_shift;
101 addr = (unsigned char *)plat->base + offset;
102
103 /*
104 * As far as we know it doesn't make sense to support selection of
105 * these options at run-time, so use the existing CONFIG options.
106 */
107 serial_out_shift(addr + plat->reg_offset, plat->reg_shift, value);
108 }
109
110 static int ns16550_readb(NS16550_t port, int offset)
111 {
112 struct ns16550_platdata *plat = port->plat;
113 unsigned char *addr;
114
115 offset *= 1 << plat->reg_shift;
116 addr = (unsigned char *)plat->base + offset;
117
118 return serial_in_shift(addr + plat->reg_offset, plat->reg_shift);
119 }
120
121 static u32 ns16550_getfcr(NS16550_t port)
122 {
123 struct ns16550_platdata *plat = port->plat;
124
125 return plat->fcr;
126 }
127
128 /* We can clean these up once everything is moved to driver model */
129 #define serial_out(value, addr) \
130 ns16550_writeb(com_port, \
131 (unsigned char *)addr - (unsigned char *)com_port, value)
132 #define serial_in(addr) \
133 ns16550_readb(com_port, \
134 (unsigned char *)addr - (unsigned char *)com_port)
135 #else
136 static u32 ns16550_getfcr(NS16550_t port)
137 {
138 return UART_FCR_DEFVAL;
139 }
140 #endif
141
142 int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate)
143 {
144 const unsigned int mode_x_div = 16;
145
146 return DIV_ROUND_CLOSEST(clock, mode_x_div * baudrate);
147 }
148
149 static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
150 {
151 serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
152 serial_out(baud_divisor & 0xff, &com_port->dll);
153 serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
154 serial_out(UART_LCRVAL, &com_port->lcr);
155 }
156
157 void NS16550_init(NS16550_t com_port, int baud_divisor)
158 {
159 #if (defined(CONFIG_SPL_BUILD) && \
160 (defined(CONFIG_OMAP34XX) || defined(CONFIG_OMAP44XX)))
161 /*
162 * On some OMAP3/OMAP4 devices when UART3 is configured for boot mode
163 * before SPL starts only THRE bit is set. We have to empty the
164 * transmitter before initialization starts.
165 */
166 if ((serial_in(&com_port->lsr) & (UART_LSR_TEMT | UART_LSR_THRE))
167 == UART_LSR_THRE) {
168 if (baud_divisor != -1)
169 NS16550_setbrg(com_port, baud_divisor);
170 serial_out(0, &com_port->mdr1);
171 }
172 #endif
173
174 while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT))
175 ;
176
177 serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
178 #if defined(CONFIG_OMAP) || defined(CONFIG_AM33XX) || \
179 defined(CONFIG_TI81XX) || defined(CONFIG_AM43XX)
180 serial_out(0x7, &com_port->mdr1); /* mode select reset TL16C750*/
181 #endif
182 serial_out(UART_MCRVAL, &com_port->mcr);
183 serial_out(ns16550_getfcr(com_port), &com_port->fcr);
184 if (baud_divisor != -1)
185 NS16550_setbrg(com_port, baud_divisor);
186 #if defined(CONFIG_OMAP) || \
187 defined(CONFIG_AM33XX) || defined(CONFIG_SOC_DA8XX) || \
188 defined(CONFIG_TI81XX) || defined(CONFIG_AM43XX)
189
190 /* /16 is proper to hit 115200 with 48MHz */
191 serial_out(0, &com_port->mdr1);
192 #endif /* CONFIG_OMAP */
193 #if defined(CONFIG_SOC_KEYSTONE)
194 serial_out(UART_REG_VAL_PWREMU_MGMT_UART_ENABLE, &com_port->regC);
195 #endif
196 }
197
198 #ifndef CONFIG_NS16550_MIN_FUNCTIONS
199 void NS16550_reinit(NS16550_t com_port, int baud_divisor)
200 {
201 serial_out(CONFIG_SYS_NS16550_IER, &com_port->ier);
202 NS16550_setbrg(com_port, 0);
203 serial_out(UART_MCRVAL, &com_port->mcr);
204 serial_out(ns16550_getfcr(com_port), &com_port->fcr);
205 NS16550_setbrg(com_port, baud_divisor);
206 }
207 #endif /* CONFIG_NS16550_MIN_FUNCTIONS */
208
209 void NS16550_putc(NS16550_t com_port, char c)
210 {
211 while ((serial_in(&com_port->lsr) & UART_LSR_THRE) == 0)
212 ;
213 serial_out(c, &com_port->thr);
214
215 /*
216 * Call watchdog_reset() upon newline. This is done here in putc
217 * since the environment code uses a single puts() to print the complete
218 * environment upon "printenv". So we can't put this watchdog call
219 * in puts().
220 */
221 if (c == '\n')
222 WATCHDOG_RESET();
223 }
224
225 #ifndef CONFIG_NS16550_MIN_FUNCTIONS
226 char NS16550_getc(NS16550_t com_port)
227 {
228 while ((serial_in(&com_port->lsr) & UART_LSR_DR) == 0) {
229 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_TTY)
230 extern void usbtty_poll(void);
231 usbtty_poll();
232 #endif
233 WATCHDOG_RESET();
234 }
235 return serial_in(&com_port->rbr);
236 }
237
238 int NS16550_tstc(NS16550_t com_port)
239 {
240 return (serial_in(&com_port->lsr) & UART_LSR_DR) != 0;
241 }
242
243 #endif /* CONFIG_NS16550_MIN_FUNCTIONS */
244
245 #ifdef CONFIG_DEBUG_UART_NS16550
246
247 #include <debug_uart.h>
248
249 static inline void _debug_uart_init(void)
250 {
251 struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
252 int baud_divisor;
253
254 /*
255 * We copy the code from above because it is already horribly messy.
256 * Trying to refactor to nicely remove the duplication doesn't seem
257 * feasible. The better fix is to move all users of this driver to
258 * driver model.
259 */
260 baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
261 CONFIG_BAUDRATE);
262 serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
263 serial_dout(&com_port->mcr, UART_MCRVAL);
264 serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
265
266 serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
267 serial_dout(&com_port->dll, baud_divisor & 0xff);
268 serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
269 serial_dout(&com_port->lcr, UART_LCRVAL);
270 }
271
272 static inline void _debug_uart_putc(int ch)
273 {
274 struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
275
276 while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
277 ;
278 serial_dout(&com_port->thr, ch);
279 }
280
281 DEBUG_UART_FUNCS
282
283 #endif
284
285 #ifdef CONFIG_DEBUG_UART_OMAP
286
287 #include <debug_uart.h>
288
289 static inline void _debug_uart_init(void)
290 {
291 struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
292 int baud_divisor;
293
294 baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
295 CONFIG_BAUDRATE);
296 serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
297 serial_dout(&com_port->mdr1, 0x7);
298 serial_dout(&com_port->mcr, UART_MCRVAL);
299 serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
300
301 serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
302 serial_dout(&com_port->dll, baud_divisor & 0xff);
303 serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
304 serial_dout(&com_port->lcr, UART_LCRVAL);
305 serial_dout(&com_port->mdr1, 0x0);
306 }
307
308 static inline void _debug_uart_putc(int ch)
309 {
310 struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
311
312 while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
313 ;
314 serial_dout(&com_port->thr, ch);
315 }
316
317 DEBUG_UART_FUNCS
318
319 #endif
320
321 #ifdef CONFIG_DM_SERIAL
322 static int ns16550_serial_putc(struct udevice *dev, const char ch)
323 {
324 struct NS16550 *const com_port = dev_get_priv(dev);
325
326 if (!(serial_in(&com_port->lsr) & UART_LSR_THRE))
327 return -EAGAIN;
328 serial_out(ch, &com_port->thr);
329
330 /*
331 * Call watchdog_reset() upon newline. This is done here in putc
332 * since the environment code uses a single puts() to print the complete
333 * environment upon "printenv". So we can't put this watchdog call
334 * in puts().
335 */
336 if (ch == '\n')
337 WATCHDOG_RESET();
338
339 return 0;
340 }
341
342 static int ns16550_serial_pending(struct udevice *dev, bool input)
343 {
344 struct NS16550 *const com_port = dev_get_priv(dev);
345
346 if (input)
347 return serial_in(&com_port->lsr) & UART_LSR_DR ? 1 : 0;
348 else
349 return serial_in(&com_port->lsr) & UART_LSR_THRE ? 0 : 1;
350 }
351
352 static int ns16550_serial_getc(struct udevice *dev)
353 {
354 struct NS16550 *const com_port = dev_get_priv(dev);
355
356 if (!(serial_in(&com_port->lsr) & UART_LSR_DR))
357 return -EAGAIN;
358
359 return serial_in(&com_port->rbr);
360 }
361
362 static int ns16550_serial_setbrg(struct udevice *dev, int baudrate)
363 {
364 struct NS16550 *const com_port = dev_get_priv(dev);
365 struct ns16550_platdata *plat = com_port->plat;
366 int clock_divisor;
367
368 clock_divisor = ns16550_calc_divisor(com_port, plat->clock, baudrate);
369
370 NS16550_setbrg(com_port, clock_divisor);
371
372 return 0;
373 }
374
375 int ns16550_serial_probe(struct udevice *dev)
376 {
377 struct NS16550 *const com_port = dev_get_priv(dev);
378
379 com_port->plat = dev_get_platdata(dev);
380 NS16550_init(com_port, -1);
381
382 return 0;
383 }
384
385 #if CONFIG_IS_ENABLED(OF_CONTROL)
386 enum {
387 PORT_NS16550 = 0,
388 PORT_JZ4780,
389 };
390 #endif
391
392 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
393 int ns16550_serial_ofdata_to_platdata(struct udevice *dev)
394 {
395 struct ns16550_platdata *plat = dev->platdata;
396 const u32 port_type = dev_get_driver_data(dev);
397 fdt_addr_t addr;
398 struct clk clk;
399 int err;
400
401 /* try Processor Local Bus device first */
402 addr = dev_get_addr(dev);
403 #if defined(CONFIG_PCI) && defined(CONFIG_DM_PCI)
404 if (addr == FDT_ADDR_T_NONE) {
405 /* then try pci device */
406 struct fdt_pci_addr pci_addr;
407 u32 bar;
408 int ret;
409
410 /* we prefer to use a memory-mapped register */
411 ret = fdtdec_get_pci_addr(gd->fdt_blob, dev_of_offset(dev),
412 FDT_PCI_SPACE_MEM32, "reg",
413 &pci_addr);
414 if (ret) {
415 /* try if there is any i/o-mapped register */
416 ret = fdtdec_get_pci_addr(gd->fdt_blob,
417 dev_of_offset(dev),
418 FDT_PCI_SPACE_IO,
419 "reg", &pci_addr);
420 if (ret)
421 return ret;
422 }
423
424 ret = fdtdec_get_pci_bar32(dev, &pci_addr, &bar);
425 if (ret)
426 return ret;
427
428 addr = bar;
429 }
430 #endif
431
432 if (addr == FDT_ADDR_T_NONE)
433 return -EINVAL;
434
435 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
436 plat->base = addr;
437 #else
438 plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE);
439 #endif
440
441 plat->reg_offset = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
442 "reg-offset", 0);
443 plat->reg_shift = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
444 "reg-shift", 0);
445
446 err = clk_get_by_index(dev, 0, &clk);
447 if (!err) {
448 err = clk_get_rate(&clk);
449 if (!IS_ERR_VALUE(err))
450 plat->clock = err;
451 } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) {
452 debug("ns16550 failed to get clock\n");
453 return err;
454 }
455
456 if (!plat->clock)
457 plat->clock = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
458 "clock-frequency",
459 CONFIG_SYS_NS16550_CLK);
460 if (!plat->clock) {
461 debug("ns16550 clock not defined\n");
462 return -EINVAL;
463 }
464
465 plat->fcr = UART_FCR_DEFVAL;
466 if (port_type == PORT_JZ4780)
467 plat->fcr |= UART_FCR_UME;
468
469 return 0;
470 }
471 #endif
472
473 const struct dm_serial_ops ns16550_serial_ops = {
474 .putc = ns16550_serial_putc,
475 .pending = ns16550_serial_pending,
476 .getc = ns16550_serial_getc,
477 .setbrg = ns16550_serial_setbrg,
478 };
479
480 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
481 /*
482 * Please consider existing compatible strings before adding a new
483 * one to keep this table compact. Or you may add a generic "ns16550"
484 * compatible string to your dts.
485 */
486 static const struct udevice_id ns16550_serial_ids[] = {
487 { .compatible = "ns16550", .data = PORT_NS16550 },
488 { .compatible = "ns16550a", .data = PORT_NS16550 },
489 { .compatible = "ingenic,jz4780-uart", .data = PORT_JZ4780 },
490 { .compatible = "nvidia,tegra20-uart", .data = PORT_NS16550 },
491 { .compatible = "snps,dw-apb-uart", .data = PORT_NS16550 },
492 { .compatible = "ti,omap2-uart", .data = PORT_NS16550 },
493 { .compatible = "ti,omap3-uart", .data = PORT_NS16550 },
494 { .compatible = "ti,omap4-uart", .data = PORT_NS16550 },
495 { .compatible = "ti,am3352-uart", .data = PORT_NS16550 },
496 { .compatible = "ti,am4372-uart", .data = PORT_NS16550 },
497 { .compatible = "ti,dra742-uart", .data = PORT_NS16550 },
498 {}
499 };
500 #endif /* OF_CONTROL && !OF_PLATDATA */
501
502 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
503
504 /* TODO(sjg@chromium.org): Integrate this into a macro like CONFIG_IS_ENABLED */
505 #if !defined(CONFIG_TPL_BUILD) || defined(CONFIG_TPL_DM_SERIAL)
506 U_BOOT_DRIVER(ns16550_serial) = {
507 .name = "ns16550_serial",
508 .id = UCLASS_SERIAL,
509 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
510 .of_match = ns16550_serial_ids,
511 .ofdata_to_platdata = ns16550_serial_ofdata_to_platdata,
512 .platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
513 #endif
514 .priv_auto_alloc_size = sizeof(struct NS16550),
515 .probe = ns16550_serial_probe,
516 .ops = &ns16550_serial_ops,
517 .flags = DM_FLAG_PRE_RELOC,
518 };
519 #endif
520 #endif /* SERIAL_PRESENT */
521
522 #endif /* CONFIG_DM_SERIAL */
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