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1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/serial.h>
4#include <linux/serial_8250.h>
5#include <linux/serial_core.h>
6#include <linux/console.h>
7#include <linux/pci.h>
8#include <linux/of_address.h>
9#include <linux/of_device.h>
10#include <linux/of_irq.h>
11#include <linux/serial_reg.h>
12#include <asm/io.h>
13#include <asm/mmu.h>
14#include <asm/serial.h>
15#include <asm/udbg.h>
16#include <asm/pci-bridge.h>
17#include <asm/ppc-pci.h>
18#include <asm/early_ioremap.h>
19
20#undef DEBUG
21
22#ifdef DEBUG
23#define DBG(fmt...) do { printk(fmt); } while(0)
24#else
25#define DBG(fmt...) do { } while(0)
26#endif
27
28#define MAX_LEGACY_SERIAL_PORTS 8
29
30static struct plat_serial8250_port
31legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1];
32static struct legacy_serial_info {
33 struct device_node *np;
34 unsigned int speed;
35 unsigned int clock;
36 int irq_check_parent;
37 phys_addr_t taddr;
38 void __iomem *early_addr;
39} legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS];
40
41static const struct of_device_id legacy_serial_parents[] __initconst = {
42 {.type = "soc",},
43 {.type = "tsi-bridge",},
44 {.type = "opb", },
45 {.compatible = "ibm,opb",},
46 {.compatible = "simple-bus",},
47 {.compatible = "wrs,epld-localbus",},
48 {},
49};
50
51static unsigned int legacy_serial_count;
52static int legacy_serial_console = -1;
53
54static const upf_t legacy_port_flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
55 UPF_SHARE_IRQ | UPF_FIXED_PORT;
56
57static unsigned int tsi_serial_in(struct uart_port *p, int offset)
58{
59 unsigned int tmp;
60 offset = offset << p->regshift;
61 if (offset == UART_IIR) {
62 tmp = readl(p->membase + (UART_IIR & ~3));
63 return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
64 } else
65 return readb(p->membase + offset);
66}
67
68static void tsi_serial_out(struct uart_port *p, int offset, int value)
69{
70 offset = offset << p->regshift;
71 if (!((offset == UART_IER) && (value & UART_IER_UUE)))
72 writeb(value, p->membase + offset);
73}
74
75static int __init add_legacy_port(struct device_node *np, int want_index,
76 int iotype, phys_addr_t base,
77 phys_addr_t taddr, unsigned long irq,
78 upf_t flags, int irq_check_parent)
79{
80 const __be32 *clk, *spd, *rs;
81 u32 clock = BASE_BAUD * 16;
82 u32 shift = 0;
83 int index;
84
85 /* get clock freq. if present */
86 clk = of_get_property(np, "clock-frequency", NULL);
87 if (clk && *clk)
88 clock = be32_to_cpup(clk);
89
90 /* get default speed if present */
91 spd = of_get_property(np, "current-speed", NULL);
92
93 /* get register shift if present */
94 rs = of_get_property(np, "reg-shift", NULL);
95 if (rs && *rs)
96 shift = be32_to_cpup(rs);
97
98 /* If we have a location index, then try to use it */
99 if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS)
100 index = want_index;
101 else
102 index = legacy_serial_count;
103
104 /* if our index is still out of range, that mean that
105 * array is full, we could scan for a free slot but that
106 * make little sense to bother, just skip the port
107 */
108 if (index >= MAX_LEGACY_SERIAL_PORTS)
109 return -1;
110 if (index >= legacy_serial_count)
111 legacy_serial_count = index + 1;
112
113 /* Check if there is a port who already claimed our slot */
114 if (legacy_serial_infos[index].np != NULL) {
115 /* if we still have some room, move it, else override */
116 if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) {
117 printk(KERN_DEBUG "Moved legacy port %d -> %d\n",
118 index, legacy_serial_count);
119 legacy_serial_ports[legacy_serial_count] =
120 legacy_serial_ports[index];
121 legacy_serial_infos[legacy_serial_count] =
122 legacy_serial_infos[index];
123 legacy_serial_count++;
124 } else {
125 printk(KERN_DEBUG "Replacing legacy port %d\n", index);
126 }
127 }
128
129 /* Now fill the entry */
130 memset(&legacy_serial_ports[index], 0,
131 sizeof(struct plat_serial8250_port));
132 if (iotype == UPIO_PORT)
133 legacy_serial_ports[index].iobase = base;
134 else
135 legacy_serial_ports[index].mapbase = base;
136
137 legacy_serial_ports[index].iotype = iotype;
138 legacy_serial_ports[index].uartclk = clock;
139 legacy_serial_ports[index].irq = irq;
140 legacy_serial_ports[index].flags = flags;
141 legacy_serial_ports[index].regshift = shift;
142 legacy_serial_infos[index].taddr = taddr;
143 legacy_serial_infos[index].np = of_node_get(np);
144 legacy_serial_infos[index].clock = clock;
145 legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0;
146 legacy_serial_infos[index].irq_check_parent = irq_check_parent;
147
148 if (iotype == UPIO_TSI) {
149 legacy_serial_ports[index].serial_in = tsi_serial_in;
150 legacy_serial_ports[index].serial_out = tsi_serial_out;
151 }
152
153 printk(KERN_DEBUG "Found legacy serial port %d for %pOF\n",
154 index, np);
155 printk(KERN_DEBUG " %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n",
156 (iotype == UPIO_PORT) ? "port" : "mem",
157 (unsigned long long)base, (unsigned long long)taddr, irq,
158 legacy_serial_ports[index].uartclk,
159 legacy_serial_infos[index].speed);
160
161 return index;
162}
163
164static int __init add_legacy_soc_port(struct device_node *np,
165 struct device_node *soc_dev)
166{
167 u64 addr;
168 const __be32 *addrp;
169 struct device_node *tsi = of_get_parent(np);
170
171 /* We only support ports that have a clock frequency properly
172 * encoded in the device-tree.
173 */
174 if (of_get_property(np, "clock-frequency", NULL) == NULL)
175 return -1;
176
177 /* if reg-offset don't try to use it */
178 if ((of_get_property(np, "reg-offset", NULL) != NULL))
179 return -1;
180
181 /* if rtas uses this device, don't try to use it as well */
182 if (of_get_property(np, "used-by-rtas", NULL) != NULL)
183 return -1;
184
185 /* Get the address */
186 addrp = of_get_address(soc_dev, 0, NULL, NULL);
187 if (addrp == NULL)
188 return -1;
189
190 addr = of_translate_address(soc_dev, addrp);
191 if (addr == OF_BAD_ADDR)
192 return -1;
193
194 /* Add port, irq will be dealt with later. We passed a translated
195 * IO port value. It will be fixed up later along with the irq
196 */
197 if (of_node_is_type(tsi, "tsi-bridge"))
198 return add_legacy_port(np, -1, UPIO_TSI, addr, addr,
199 0, legacy_port_flags, 0);
200 else
201 return add_legacy_port(np, -1, UPIO_MEM, addr, addr,
202 0, legacy_port_flags, 0);
203}
204
205static int __init add_legacy_isa_port(struct device_node *np,
206 struct device_node *isa_brg)
207{
208 const __be32 *reg;
209 const char *typep;
210 int index = -1;
211 u64 taddr;
212
213 DBG(" -> add_legacy_isa_port(%pOF)\n", np);
214
215 /* Get the ISA port number */
216 reg = of_get_property(np, "reg", NULL);
217 if (reg == NULL)
218 return -1;
219
220 /* Verify it's an IO port, we don't support anything else */
221 if (!(be32_to_cpu(reg[0]) & 0x00000001))
222 return -1;
223
224 /* Now look for an "ibm,aix-loc" property that gives us ordering
225 * if any...
226 */
227 typep = of_get_property(np, "ibm,aix-loc", NULL);
228
229 /* If we have a location index, then use it */
230 if (typep && *typep == 'S')
231 index = simple_strtol(typep+1, NULL, 0) - 1;
232
233 /* Translate ISA address. If it fails, we still register the port
234 * with no translated address so that it can be picked up as an IO
235 * port later by the serial driver
236 *
237 * Note: Don't even try on P8 lpc, we know it's not directly mapped
238 */
239 if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc") ||
240 of_get_property(isa_brg, "ranges", NULL)) {
241 taddr = of_translate_address(np, reg);
242 if (taddr == OF_BAD_ADDR)
243 taddr = 0;
244 } else
245 taddr = 0;
246
247 /* Add port, irq will be dealt with later */
248 return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]),
249 taddr, 0, legacy_port_flags, 0);
250
251}
252
253#ifdef CONFIG_PCI
254static int __init add_legacy_pci_port(struct device_node *np,
255 struct device_node *pci_dev)
256{
257 u64 addr, base;
258 const __be32 *addrp;
259 unsigned int flags;
260 int iotype, index = -1, lindex = 0;
261
262 DBG(" -> add_legacy_pci_port(%pOF)\n", np);
263
264 /* We only support ports that have a clock frequency properly
265 * encoded in the device-tree (that is have an fcode). Anything
266 * else can't be used that early and will be normally probed by
267 * the generic 8250_pci driver later on. The reason is that 8250
268 * compatible UARTs on PCI need all sort of quirks (port offsets
269 * etc...) that this code doesn't know about
270 */
271 if (of_get_property(np, "clock-frequency", NULL) == NULL)
272 return -1;
273
274 /* Get the PCI address. Assume BAR 0 */
275 addrp = of_get_pci_address(pci_dev, 0, NULL, &flags);
276 if (addrp == NULL)
277 return -1;
278
279 /* We only support BAR 0 for now */
280 iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT;
281 addr = of_translate_address(pci_dev, addrp);
282 if (addr == OF_BAD_ADDR)
283 return -1;
284
285 /* Set the IO base to the same as the translated address for MMIO,
286 * or to the domain local IO base for PIO (it will be fixed up later)
287 */
288 if (iotype == UPIO_MEM)
289 base = addr;
290 else
291 base = of_read_number(&addrp[2], 1);
292
293 /* Try to guess an index... If we have subdevices of the pci dev,
294 * we get to their "reg" property
295 */
296 if (np != pci_dev) {
297 const __be32 *reg = of_get_property(np, "reg", NULL);
298 if (reg && (be32_to_cpup(reg) < 4))
299 index = lindex = be32_to_cpup(reg);
300 }
301
302 /* Local index means it's the Nth port in the PCI chip. Unfortunately
303 * the offset to add here is device specific. We know about those
304 * EXAR ports and we default to the most common case. If your UART
305 * doesn't work for these settings, you'll have to add your own special
306 * cases here
307 */
308 if (of_device_is_compatible(pci_dev, "pci13a8,152") ||
309 of_device_is_compatible(pci_dev, "pci13a8,154") ||
310 of_device_is_compatible(pci_dev, "pci13a8,158")) {
311 addr += 0x200 * lindex;
312 base += 0x200 * lindex;
313 } else {
314 addr += 8 * lindex;
315 base += 8 * lindex;
316 }
317
318 /* Add port, irq will be dealt with later. We passed a translated
319 * IO port value. It will be fixed up later along with the irq
320 */
321 return add_legacy_port(np, index, iotype, base, addr, 0,
322 legacy_port_flags, np != pci_dev);
323}
324#endif
325
326static void __init setup_legacy_serial_console(int console)
327{
328 struct legacy_serial_info *info = &legacy_serial_infos[console];
329 struct plat_serial8250_port *port = &legacy_serial_ports[console];
330 unsigned int stride;
331
332 stride = 1 << port->regshift;
333
334 /* Check if a translated MMIO address has been found */
335 if (info->taddr) {
336 info->early_addr = early_ioremap(info->taddr, 0x1000);
337 if (info->early_addr == NULL)
338 return;
339 udbg_uart_init_mmio(info->early_addr, stride);
340 } else {
341 /* Check if it's PIO and we support untranslated PIO */
342 if (port->iotype == UPIO_PORT && isa_io_special)
343 udbg_uart_init_pio(port->iobase, stride);
344 else
345 return;
346 }
347
348 /* Try to query the current speed */
349 if (info->speed == 0)
350 info->speed = udbg_probe_uart_speed(info->clock);
351
352 /* Set it up */
353 DBG("default console speed = %d\n", info->speed);
354 udbg_uart_setup(info->speed, info->clock);
355}
356
357static int __init ioremap_legacy_serial_console(void)
358{
359 struct plat_serial8250_port *port;
360 struct legacy_serial_info *info;
361 void __iomem *vaddr;
362
363 if (legacy_serial_console < 0)
364 return 0;
365
366 info = &legacy_serial_infos[legacy_serial_console];
367 port = &legacy_serial_ports[legacy_serial_console];
368
369 if (!info->early_addr)
370 return 0;
371
372 vaddr = ioremap(info->taddr, 0x1000);
373 if (WARN_ON(!vaddr))
374 return -ENOMEM;
375
376 udbg_uart_init_mmio(vaddr, 1 << port->regshift);
377 early_iounmap(info->early_addr, 0x1000);
378 info->early_addr = NULL;
379
380 return 0;
381}
382early_initcall(ioremap_legacy_serial_console);
383
384/*
385 * This is called very early, as part of setup_system() or eventually
386 * setup_arch(), basically before anything else in this file. This function
387 * will try to build a list of all the available 8250-compatible serial ports
388 * in the machine using the Open Firmware device-tree. It currently only deals
389 * with ISA and PCI busses but could be extended. It allows a very early boot
390 * console to be initialized, that list is also used later to provide 8250 with
391 * the machine non-PCI ports and to properly pick the default console port
392 */
393void __init find_legacy_serial_ports(void)
394{
395 struct device_node *np, *stdout = NULL;
396 const char *path;
397 int index;
398
399 DBG(" -> find_legacy_serial_port()\n");
400
401 /* Now find out if one of these is out firmware console */
402 path = of_get_property(of_chosen, "linux,stdout-path", NULL);
403 if (path == NULL)
404 path = of_get_property(of_chosen, "stdout-path", NULL);
405 if (path != NULL) {
406 stdout = of_find_node_by_path(path);
407 if (stdout)
408 DBG("stdout is %pOF\n", stdout);
409 } else {
410 DBG(" no linux,stdout-path !\n");
411 }
412
413 /* Iterate over all the 16550 ports, looking for known parents */
414 for_each_compatible_node(np, "serial", "ns16550") {
415 struct device_node *parent = of_get_parent(np);
416 if (!parent)
417 continue;
418 if (of_match_node(legacy_serial_parents, parent) != NULL) {
419 if (of_device_is_available(np)) {
420 index = add_legacy_soc_port(np, np);
421 if (index >= 0 && np == stdout)
422 legacy_serial_console = index;
423 }
424 }
425 of_node_put(parent);
426 }
427
428 /* Next, fill our array with ISA ports */
429 for_each_node_by_type(np, "serial") {
430 struct device_node *isa = of_get_parent(np);
431 if (of_node_name_eq(isa, "isa") || of_node_name_eq(isa, "lpc")) {
432 if (of_device_is_available(np)) {
433 index = add_legacy_isa_port(np, isa);
434 if (index >= 0 && np == stdout)
435 legacy_serial_console = index;
436 }
437 }
438 of_node_put(isa);
439 }
440
441#ifdef CONFIG_PCI
442 /* Next, try to locate PCI ports */
443 for (np = NULL; (np = of_find_all_nodes(np));) {
444 struct device_node *pci, *parent = of_get_parent(np);
445 if (of_node_name_eq(parent, "isa")) {
446 of_node_put(parent);
447 continue;
448 }
449 if (!of_node_name_eq(np, "serial") &&
450 !of_node_is_type(np, "serial")) {
451 of_node_put(parent);
452 continue;
453 }
454 /* Check for known pciclass, and also check whether we have
455 * a device with child nodes for ports or not
456 */
457 if (of_device_is_compatible(np, "pciclass,0700") ||
458 of_device_is_compatible(np, "pciclass,070002"))
459 pci = np;
460 else if (of_device_is_compatible(parent, "pciclass,0700") ||
461 of_device_is_compatible(parent, "pciclass,070002"))
462 pci = parent;
463 else {
464 of_node_put(parent);
465 continue;
466 }
467 index = add_legacy_pci_port(np, pci);
468 if (index >= 0 && np == stdout)
469 legacy_serial_console = index;
470 of_node_put(parent);
471 }
472#endif
473
474 of_node_put(stdout);
475
476 DBG("legacy_serial_console = %d\n", legacy_serial_console);
477 if (legacy_serial_console >= 0)
478 setup_legacy_serial_console(legacy_serial_console);
479 DBG(" <- find_legacy_serial_port()\n");
480}
481
482static struct platform_device serial_device = {
483 .name = "serial8250",
484 .id = PLAT8250_DEV_PLATFORM,
485 .dev = {
486 .platform_data = legacy_serial_ports,
487 },
488};
489
490static void __init fixup_port_irq(int index,
491 struct device_node *np,
492 struct plat_serial8250_port *port)
493{
494 unsigned int virq;
495
496 DBG("fixup_port_irq(%d)\n", index);
497
498 virq = irq_of_parse_and_map(np, 0);
499 if (!virq && legacy_serial_infos[index].irq_check_parent) {
500 np = of_get_parent(np);
501 if (np == NULL)
502 return;
503 virq = irq_of_parse_and_map(np, 0);
504 of_node_put(np);
505 }
506 if (!virq)
507 return;
508
509 port->irq = virq;
510
511#ifdef CONFIG_SERIAL_8250_FSL
512 if (of_device_is_compatible(np, "fsl,ns16550")) {
513 port->handle_irq = fsl8250_handle_irq;
514 port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE);
515 }
516#endif
517}
518
519static void __init fixup_port_pio(int index,
520 struct device_node *np,
521 struct plat_serial8250_port *port)
522{
523#ifdef CONFIG_PCI
524 struct pci_controller *hose;
525
526 DBG("fixup_port_pio(%d)\n", index);
527
528 hose = pci_find_hose_for_OF_device(np);
529 if (hose) {
530 unsigned long offset = (unsigned long)hose->io_base_virt -
531#ifdef CONFIG_PPC64
532 pci_io_base;
533#else
534 isa_io_base;
535#endif
536 DBG("port %d, IO %lx -> %lx\n",
537 index, port->iobase, port->iobase + offset);
538 port->iobase += offset;
539 }
540#endif
541}
542
543static void __init fixup_port_mmio(int index,
544 struct device_node *np,
545 struct plat_serial8250_port *port)
546{
547 DBG("fixup_port_mmio(%d)\n", index);
548
549 port->membase = ioremap(port->mapbase, 0x100);
550}
551
552/*
553 * This is called as an arch initcall, hopefully before the PCI bus is
554 * probed and/or the 8250 driver loaded since we need to register our
555 * platform devices before 8250 PCI ones are detected as some of them
556 * must properly "override" the platform ones.
557 *
558 * This function fixes up the interrupt value for platform ports as it
559 * couldn't be done earlier before interrupt maps have been parsed. It
560 * also "corrects" the IO address for PIO ports for the same reason,
561 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then
562 * registers all those platform ports for use by the 8250 driver when it
563 * finally loads.
564 */
565static int __init serial_dev_init(void)
566{
567 int i;
568
569 if (legacy_serial_count == 0)
570 return -ENODEV;
571
572 /*
573 * Before we register the platform serial devices, we need
574 * to fixup their interrupts and their IO ports.
575 */
576 DBG("Fixing serial ports interrupts and IO ports ...\n");
577
578 for (i = 0; i < legacy_serial_count; i++) {
579 struct plat_serial8250_port *port = &legacy_serial_ports[i];
580 struct device_node *np = legacy_serial_infos[i].np;
581
582 if (!port->irq)
583 fixup_port_irq(i, np, port);
584 if (port->iotype == UPIO_PORT)
585 fixup_port_pio(i, np, port);
586 if ((port->iotype == UPIO_MEM) || (port->iotype == UPIO_TSI))
587 fixup_port_mmio(i, np, port);
588 }
589
590 DBG("Registering platform serial ports\n");
591
592 return platform_device_register(&serial_device);
593}
594device_initcall(serial_dev_init);
595
596
597#ifdef CONFIG_SERIAL_8250_CONSOLE
598/*
599 * This is called very early, as part of console_init() (typically just after
600 * time_init()). This function is respondible for trying to find a good
601 * default console on serial ports. It tries to match the open firmware
602 * default output with one of the available serial console drivers that have
603 * been probed earlier by find_legacy_serial_ports()
604 */
605static int __init check_legacy_serial_console(void)
606{
607 struct device_node *prom_stdout = NULL;
608 int i, speed = 0, offset = 0;
609 const char *name;
610 const __be32 *spd;
611
612 DBG(" -> check_legacy_serial_console()\n");
613
614 /* The user has requested a console so this is already set up. */
615 if (strstr(boot_command_line, "console=")) {
616 DBG(" console was specified !\n");
617 return -EBUSY;
618 }
619
620 if (!of_chosen) {
621 DBG(" of_chosen is NULL !\n");
622 return -ENODEV;
623 }
624
625 if (legacy_serial_console < 0) {
626 DBG(" legacy_serial_console not found !\n");
627 return -ENODEV;
628 }
629 /* We are getting a weird phandle from OF ... */
630 /* ... So use the full path instead */
631 name = of_get_property(of_chosen, "linux,stdout-path", NULL);
632 if (name == NULL)
633 name = of_get_property(of_chosen, "stdout-path", NULL);
634 if (name == NULL) {
635 DBG(" no stdout-path !\n");
636 return -ENODEV;
637 }
638 prom_stdout = of_find_node_by_path(name);
639 if (!prom_stdout) {
640 DBG(" can't find stdout package %s !\n", name);
641 return -ENODEV;
642 }
643 DBG("stdout is %pOF\n", prom_stdout);
644
645 name = of_get_property(prom_stdout, "name", NULL);
646 if (!name) {
647 DBG(" stdout package has no name !\n");
648 goto not_found;
649 }
650 spd = of_get_property(prom_stdout, "current-speed", NULL);
651 if (spd)
652 speed = be32_to_cpup(spd);
653
654 if (strcmp(name, "serial") != 0)
655 goto not_found;
656
657 /* Look for it in probed array */
658 for (i = 0; i < legacy_serial_count; i++) {
659 if (prom_stdout != legacy_serial_infos[i].np)
660 continue;
661 offset = i;
662 speed = legacy_serial_infos[i].speed;
663 break;
664 }
665 if (i >= legacy_serial_count)
666 goto not_found;
667
668 of_node_put(prom_stdout);
669
670 DBG("Found serial console at ttyS%d\n", offset);
671
672 if (speed) {
673 static char __initdata opt[16];
674 sprintf(opt, "%d", speed);
675 return add_preferred_console("ttyS", offset, opt);
676 } else
677 return add_preferred_console("ttyS", offset, NULL);
678
679 not_found:
680 DBG("No preferred console found !\n");
681 of_node_put(prom_stdout);
682 return -ENODEV;
683}
684console_initcall(check_legacy_serial_console);
685
686#endif /* CONFIG_SERIAL_8250_CONSOLE */
1#include <linux/kernel.h>
2#include <linux/serial.h>
3#include <linux/serial_8250.h>
4#include <linux/serial_core.h>
5#include <linux/console.h>
6#include <linux/pci.h>
7#include <linux/of_address.h>
8#include <linux/of_device.h>
9#include <linux/serial_reg.h>
10#include <asm/io.h>
11#include <asm/mmu.h>
12#include <asm/prom.h>
13#include <asm/serial.h>
14#include <asm/udbg.h>
15#include <asm/pci-bridge.h>
16#include <asm/ppc-pci.h>
17
18#undef DEBUG
19
20#ifdef DEBUG
21#define DBG(fmt...) do { printk(fmt); } while(0)
22#else
23#define DBG(fmt...) do { } while(0)
24#endif
25
26#define MAX_LEGACY_SERIAL_PORTS 8
27
28static struct plat_serial8250_port
29legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1];
30static struct legacy_serial_info {
31 struct device_node *np;
32 unsigned int speed;
33 unsigned int clock;
34 int irq_check_parent;
35 phys_addr_t taddr;
36} legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS];
37
38static struct of_device_id legacy_serial_parents[] __initdata = {
39 {.type = "soc",},
40 {.type = "tsi-bridge",},
41 {.type = "opb", },
42 {.compatible = "ibm,opb",},
43 {.compatible = "simple-bus",},
44 {.compatible = "wrs,epld-localbus",},
45 {},
46};
47
48static unsigned int legacy_serial_count;
49static int legacy_serial_console = -1;
50
51static unsigned int tsi_serial_in(struct uart_port *p, int offset)
52{
53 unsigned int tmp;
54 offset = offset << p->regshift;
55 if (offset == UART_IIR) {
56 tmp = readl(p->membase + (UART_IIR & ~3));
57 return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
58 } else
59 return readb(p->membase + offset);
60}
61
62static void tsi_serial_out(struct uart_port *p, int offset, int value)
63{
64 offset = offset << p->regshift;
65 if (!((offset == UART_IER) && (value & UART_IER_UUE)))
66 writeb(value, p->membase + offset);
67}
68
69static int __init add_legacy_port(struct device_node *np, int want_index,
70 int iotype, phys_addr_t base,
71 phys_addr_t taddr, unsigned long irq,
72 upf_t flags, int irq_check_parent)
73{
74 const __be32 *clk, *spd;
75 u32 clock = BASE_BAUD * 16;
76 int index;
77
78 /* get clock freq. if present */
79 clk = of_get_property(np, "clock-frequency", NULL);
80 if (clk && *clk)
81 clock = be32_to_cpup(clk);
82
83 /* get default speed if present */
84 spd = of_get_property(np, "current-speed", NULL);
85
86 /* If we have a location index, then try to use it */
87 if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS)
88 index = want_index;
89 else
90 index = legacy_serial_count;
91
92 /* if our index is still out of range, that mean that
93 * array is full, we could scan for a free slot but that
94 * make little sense to bother, just skip the port
95 */
96 if (index >= MAX_LEGACY_SERIAL_PORTS)
97 return -1;
98 if (index >= legacy_serial_count)
99 legacy_serial_count = index + 1;
100
101 /* Check if there is a port who already claimed our slot */
102 if (legacy_serial_infos[index].np != NULL) {
103 /* if we still have some room, move it, else override */
104 if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) {
105 printk(KERN_DEBUG "Moved legacy port %d -> %d\n",
106 index, legacy_serial_count);
107 legacy_serial_ports[legacy_serial_count] =
108 legacy_serial_ports[index];
109 legacy_serial_infos[legacy_serial_count] =
110 legacy_serial_infos[index];
111 legacy_serial_count++;
112 } else {
113 printk(KERN_DEBUG "Replacing legacy port %d\n", index);
114 }
115 }
116
117 /* Now fill the entry */
118 memset(&legacy_serial_ports[index], 0,
119 sizeof(struct plat_serial8250_port));
120 if (iotype == UPIO_PORT)
121 legacy_serial_ports[index].iobase = base;
122 else
123 legacy_serial_ports[index].mapbase = base;
124
125 legacy_serial_ports[index].iotype = iotype;
126 legacy_serial_ports[index].uartclk = clock;
127 legacy_serial_ports[index].irq = irq;
128 legacy_serial_ports[index].flags = flags;
129 legacy_serial_infos[index].taddr = taddr;
130 legacy_serial_infos[index].np = of_node_get(np);
131 legacy_serial_infos[index].clock = clock;
132 legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0;
133 legacy_serial_infos[index].irq_check_parent = irq_check_parent;
134
135 if (iotype == UPIO_TSI) {
136 legacy_serial_ports[index].serial_in = tsi_serial_in;
137 legacy_serial_ports[index].serial_out = tsi_serial_out;
138 }
139
140 printk(KERN_DEBUG "Found legacy serial port %d for %s\n",
141 index, np->full_name);
142 printk(KERN_DEBUG " %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n",
143 (iotype == UPIO_PORT) ? "port" : "mem",
144 (unsigned long long)base, (unsigned long long)taddr, irq,
145 legacy_serial_ports[index].uartclk,
146 legacy_serial_infos[index].speed);
147
148 return index;
149}
150
151static int __init add_legacy_soc_port(struct device_node *np,
152 struct device_node *soc_dev)
153{
154 u64 addr;
155 const __be32 *addrp;
156 upf_t flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST | UPF_SHARE_IRQ
157 | UPF_FIXED_PORT;
158 struct device_node *tsi = of_get_parent(np);
159
160 /* We only support ports that have a clock frequency properly
161 * encoded in the device-tree.
162 */
163 if (of_get_property(np, "clock-frequency", NULL) == NULL)
164 return -1;
165
166 /* if reg-shift or offset, don't try to use it */
167 if ((of_get_property(np, "reg-shift", NULL) != NULL) ||
168 (of_get_property(np, "reg-offset", NULL) != NULL))
169 return -1;
170
171 /* if rtas uses this device, don't try to use it as well */
172 if (of_get_property(np, "used-by-rtas", NULL) != NULL)
173 return -1;
174
175 /* Get the address */
176 addrp = of_get_address(soc_dev, 0, NULL, NULL);
177 if (addrp == NULL)
178 return -1;
179
180 addr = of_translate_address(soc_dev, addrp);
181 if (addr == OF_BAD_ADDR)
182 return -1;
183
184 /* Add port, irq will be dealt with later. We passed a translated
185 * IO port value. It will be fixed up later along with the irq
186 */
187 if (tsi && !strcmp(tsi->type, "tsi-bridge"))
188 return add_legacy_port(np, -1, UPIO_TSI, addr, addr, NO_IRQ, flags, 0);
189 else
190 return add_legacy_port(np, -1, UPIO_MEM, addr, addr, NO_IRQ, flags, 0);
191}
192
193static int __init add_legacy_isa_port(struct device_node *np,
194 struct device_node *isa_brg)
195{
196 const __be32 *reg;
197 const char *typep;
198 int index = -1;
199 u64 taddr;
200
201 DBG(" -> add_legacy_isa_port(%s)\n", np->full_name);
202
203 /* Get the ISA port number */
204 reg = of_get_property(np, "reg", NULL);
205 if (reg == NULL)
206 return -1;
207
208 /* Verify it's an IO port, we don't support anything else */
209 if (!(be32_to_cpu(reg[0]) & 0x00000001))
210 return -1;
211
212 /* Now look for an "ibm,aix-loc" property that gives us ordering
213 * if any...
214 */
215 typep = of_get_property(np, "ibm,aix-loc", NULL);
216
217 /* If we have a location index, then use it */
218 if (typep && *typep == 'S')
219 index = simple_strtol(typep+1, NULL, 0) - 1;
220
221 /* Translate ISA address. If it fails, we still register the port
222 * with no translated address so that it can be picked up as an IO
223 * port later by the serial driver
224 *
225 * Note: Don't even try on P8 lpc, we know it's not directly mapped
226 */
227 if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc")) {
228 taddr = of_translate_address(np, reg);
229 if (taddr == OF_BAD_ADDR)
230 taddr = 0;
231 } else
232 taddr = 0;
233
234 /* Add port, irq will be dealt with later */
235 return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]),
236 taddr, NO_IRQ, UPF_BOOT_AUTOCONF, 0);
237
238}
239
240#ifdef CONFIG_PCI
241static int __init add_legacy_pci_port(struct device_node *np,
242 struct device_node *pci_dev)
243{
244 u64 addr, base;
245 const __be32 *addrp;
246 unsigned int flags;
247 int iotype, index = -1, lindex = 0;
248
249 DBG(" -> add_legacy_pci_port(%s)\n", np->full_name);
250
251 /* We only support ports that have a clock frequency properly
252 * encoded in the device-tree (that is have an fcode). Anything
253 * else can't be used that early and will be normally probed by
254 * the generic 8250_pci driver later on. The reason is that 8250
255 * compatible UARTs on PCI need all sort of quirks (port offsets
256 * etc...) that this code doesn't know about
257 */
258 if (of_get_property(np, "clock-frequency", NULL) == NULL)
259 return -1;
260
261 /* Get the PCI address. Assume BAR 0 */
262 addrp = of_get_pci_address(pci_dev, 0, NULL, &flags);
263 if (addrp == NULL)
264 return -1;
265
266 /* We only support BAR 0 for now */
267 iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT;
268 addr = of_translate_address(pci_dev, addrp);
269 if (addr == OF_BAD_ADDR)
270 return -1;
271
272 /* Set the IO base to the same as the translated address for MMIO,
273 * or to the domain local IO base for PIO (it will be fixed up later)
274 */
275 if (iotype == UPIO_MEM)
276 base = addr;
277 else
278 base = of_read_number(&addrp[2], 1);
279
280 /* Try to guess an index... If we have subdevices of the pci dev,
281 * we get to their "reg" property
282 */
283 if (np != pci_dev) {
284 const __be32 *reg = of_get_property(np, "reg", NULL);
285 if (reg && (be32_to_cpup(reg) < 4))
286 index = lindex = be32_to_cpup(reg);
287 }
288
289 /* Local index means it's the Nth port in the PCI chip. Unfortunately
290 * the offset to add here is device specific. We know about those
291 * EXAR ports and we default to the most common case. If your UART
292 * doesn't work for these settings, you'll have to add your own special
293 * cases here
294 */
295 if (of_device_is_compatible(pci_dev, "pci13a8,152") ||
296 of_device_is_compatible(pci_dev, "pci13a8,154") ||
297 of_device_is_compatible(pci_dev, "pci13a8,158")) {
298 addr += 0x200 * lindex;
299 base += 0x200 * lindex;
300 } else {
301 addr += 8 * lindex;
302 base += 8 * lindex;
303 }
304
305 /* Add port, irq will be dealt with later. We passed a translated
306 * IO port value. It will be fixed up later along with the irq
307 */
308 return add_legacy_port(np, index, iotype, base, addr, NO_IRQ,
309 UPF_BOOT_AUTOCONF, np != pci_dev);
310}
311#endif
312
313static void __init setup_legacy_serial_console(int console)
314{
315 struct legacy_serial_info *info = &legacy_serial_infos[console];
316 struct plat_serial8250_port *port = &legacy_serial_ports[console];
317 void __iomem *addr;
318
319 /* Check if a translated MMIO address has been found */
320 if (info->taddr) {
321 addr = ioremap(info->taddr, 0x1000);
322 if (addr == NULL)
323 return;
324 udbg_uart_init_mmio(addr, 1);
325 } else {
326 /* Check if it's PIO and we support untranslated PIO */
327 if (port->iotype == UPIO_PORT && isa_io_special)
328 udbg_uart_init_pio(port->iobase, 1);
329 else
330 return;
331 }
332
333 /* Try to query the current speed */
334 if (info->speed == 0)
335 info->speed = udbg_probe_uart_speed(info->clock);
336
337 /* Set it up */
338 DBG("default console speed = %d\n", info->speed);
339 udbg_uart_setup(info->speed, info->clock);
340}
341
342/*
343 * This is called very early, as part of setup_system() or eventually
344 * setup_arch(), basically before anything else in this file. This function
345 * will try to build a list of all the available 8250-compatible serial ports
346 * in the machine using the Open Firmware device-tree. It currently only deals
347 * with ISA and PCI busses but could be extended. It allows a very early boot
348 * console to be initialized, that list is also used later to provide 8250 with
349 * the machine non-PCI ports and to properly pick the default console port
350 */
351void __init find_legacy_serial_ports(void)
352{
353 struct device_node *np, *stdout = NULL;
354 const char *path;
355 int index;
356
357 DBG(" -> find_legacy_serial_port()\n");
358
359 /* Now find out if one of these is out firmware console */
360 path = of_get_property(of_chosen, "linux,stdout-path", NULL);
361 if (path != NULL) {
362 stdout = of_find_node_by_path(path);
363 if (stdout)
364 DBG("stdout is %s\n", stdout->full_name);
365 } else {
366 DBG(" no linux,stdout-path !\n");
367 }
368
369 /* Iterate over all the 16550 ports, looking for known parents */
370 for_each_compatible_node(np, "serial", "ns16550") {
371 struct device_node *parent = of_get_parent(np);
372 if (!parent)
373 continue;
374 if (of_match_node(legacy_serial_parents, parent) != NULL) {
375 if (of_device_is_available(np)) {
376 index = add_legacy_soc_port(np, np);
377 if (index >= 0 && np == stdout)
378 legacy_serial_console = index;
379 }
380 }
381 of_node_put(parent);
382 }
383
384 /* Next, fill our array with ISA ports */
385 for_each_node_by_type(np, "serial") {
386 struct device_node *isa = of_get_parent(np);
387 if (isa && (!strcmp(isa->name, "isa") ||
388 !strcmp(isa->name, "lpc"))) {
389 if (of_device_is_available(np)) {
390 index = add_legacy_isa_port(np, isa);
391 if (index >= 0 && np == stdout)
392 legacy_serial_console = index;
393 }
394 }
395 of_node_put(isa);
396 }
397
398#ifdef CONFIG_PCI
399 /* Next, try to locate PCI ports */
400 for (np = NULL; (np = of_find_all_nodes(np));) {
401 struct device_node *pci, *parent = of_get_parent(np);
402 if (parent && !strcmp(parent->name, "isa")) {
403 of_node_put(parent);
404 continue;
405 }
406 if (strcmp(np->name, "serial") && strcmp(np->type, "serial")) {
407 of_node_put(parent);
408 continue;
409 }
410 /* Check for known pciclass, and also check whether we have
411 * a device with child nodes for ports or not
412 */
413 if (of_device_is_compatible(np, "pciclass,0700") ||
414 of_device_is_compatible(np, "pciclass,070002"))
415 pci = np;
416 else if (of_device_is_compatible(parent, "pciclass,0700") ||
417 of_device_is_compatible(parent, "pciclass,070002"))
418 pci = parent;
419 else {
420 of_node_put(parent);
421 continue;
422 }
423 index = add_legacy_pci_port(np, pci);
424 if (index >= 0 && np == stdout)
425 legacy_serial_console = index;
426 of_node_put(parent);
427 }
428#endif
429
430 DBG("legacy_serial_console = %d\n", legacy_serial_console);
431 if (legacy_serial_console >= 0)
432 setup_legacy_serial_console(legacy_serial_console);
433 DBG(" <- find_legacy_serial_port()\n");
434}
435
436static struct platform_device serial_device = {
437 .name = "serial8250",
438 .id = PLAT8250_DEV_PLATFORM,
439 .dev = {
440 .platform_data = legacy_serial_ports,
441 },
442};
443
444static void __init fixup_port_irq(int index,
445 struct device_node *np,
446 struct plat_serial8250_port *port)
447{
448 unsigned int virq;
449
450 DBG("fixup_port_irq(%d)\n", index);
451
452 virq = irq_of_parse_and_map(np, 0);
453 if (virq == NO_IRQ && legacy_serial_infos[index].irq_check_parent) {
454 np = of_get_parent(np);
455 if (np == NULL)
456 return;
457 virq = irq_of_parse_and_map(np, 0);
458 of_node_put(np);
459 }
460 if (virq == NO_IRQ)
461 return;
462
463 port->irq = virq;
464
465#ifdef CONFIG_SERIAL_8250_FSL
466 if (of_device_is_compatible(np, "fsl,ns16550"))
467 port->handle_irq = fsl8250_handle_irq;
468#endif
469}
470
471static void __init fixup_port_pio(int index,
472 struct device_node *np,
473 struct plat_serial8250_port *port)
474{
475#ifdef CONFIG_PCI
476 struct pci_controller *hose;
477
478 DBG("fixup_port_pio(%d)\n", index);
479
480 hose = pci_find_hose_for_OF_device(np);
481 if (hose) {
482 unsigned long offset = (unsigned long)hose->io_base_virt -
483#ifdef CONFIG_PPC64
484 pci_io_base;
485#else
486 isa_io_base;
487#endif
488 DBG("port %d, IO %lx -> %lx\n",
489 index, port->iobase, port->iobase + offset);
490 port->iobase += offset;
491 }
492#endif
493}
494
495static void __init fixup_port_mmio(int index,
496 struct device_node *np,
497 struct plat_serial8250_port *port)
498{
499 DBG("fixup_port_mmio(%d)\n", index);
500
501 port->membase = ioremap(port->mapbase, 0x100);
502}
503
504/*
505 * This is called as an arch initcall, hopefully before the PCI bus is
506 * probed and/or the 8250 driver loaded since we need to register our
507 * platform devices before 8250 PCI ones are detected as some of them
508 * must properly "override" the platform ones.
509 *
510 * This function fixes up the interrupt value for platform ports as it
511 * couldn't be done earlier before interrupt maps have been parsed. It
512 * also "corrects" the IO address for PIO ports for the same reason,
513 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then
514 * registers all those platform ports for use by the 8250 driver when it
515 * finally loads.
516 */
517static int __init serial_dev_init(void)
518{
519 int i;
520
521 if (legacy_serial_count == 0)
522 return -ENODEV;
523
524 /*
525 * Before we register the platform serial devices, we need
526 * to fixup their interrupts and their IO ports.
527 */
528 DBG("Fixing serial ports interrupts and IO ports ...\n");
529
530 for (i = 0; i < legacy_serial_count; i++) {
531 struct plat_serial8250_port *port = &legacy_serial_ports[i];
532 struct device_node *np = legacy_serial_infos[i].np;
533
534 if (port->irq == NO_IRQ)
535 fixup_port_irq(i, np, port);
536 if (port->iotype == UPIO_PORT)
537 fixup_port_pio(i, np, port);
538 if ((port->iotype == UPIO_MEM) || (port->iotype == UPIO_TSI))
539 fixup_port_mmio(i, np, port);
540 }
541
542 DBG("Registering platform serial ports\n");
543
544 return platform_device_register(&serial_device);
545}
546device_initcall(serial_dev_init);
547
548
549#ifdef CONFIG_SERIAL_8250_CONSOLE
550/*
551 * This is called very early, as part of console_init() (typically just after
552 * time_init()). This function is respondible for trying to find a good
553 * default console on serial ports. It tries to match the open firmware
554 * default output with one of the available serial console drivers that have
555 * been probed earlier by find_legacy_serial_ports()
556 */
557static int __init check_legacy_serial_console(void)
558{
559 struct device_node *prom_stdout = NULL;
560 int i, speed = 0, offset = 0;
561 const char *name;
562 const __be32 *spd;
563
564 DBG(" -> check_legacy_serial_console()\n");
565
566 /* The user has requested a console so this is already set up. */
567 if (strstr(boot_command_line, "console=")) {
568 DBG(" console was specified !\n");
569 return -EBUSY;
570 }
571
572 if (!of_chosen) {
573 DBG(" of_chosen is NULL !\n");
574 return -ENODEV;
575 }
576
577 if (legacy_serial_console < 0) {
578 DBG(" legacy_serial_console not found !\n");
579 return -ENODEV;
580 }
581 /* We are getting a weird phandle from OF ... */
582 /* ... So use the full path instead */
583 name = of_get_property(of_chosen, "linux,stdout-path", NULL);
584 if (name == NULL) {
585 DBG(" no linux,stdout-path !\n");
586 return -ENODEV;
587 }
588 prom_stdout = of_find_node_by_path(name);
589 if (!prom_stdout) {
590 DBG(" can't find stdout package %s !\n", name);
591 return -ENODEV;
592 }
593 DBG("stdout is %s\n", prom_stdout->full_name);
594
595 name = of_get_property(prom_stdout, "name", NULL);
596 if (!name) {
597 DBG(" stdout package has no name !\n");
598 goto not_found;
599 }
600 spd = of_get_property(prom_stdout, "current-speed", NULL);
601 if (spd)
602 speed = be32_to_cpup(spd);
603
604 if (strcmp(name, "serial") != 0)
605 goto not_found;
606
607 /* Look for it in probed array */
608 for (i = 0; i < legacy_serial_count; i++) {
609 if (prom_stdout != legacy_serial_infos[i].np)
610 continue;
611 offset = i;
612 speed = legacy_serial_infos[i].speed;
613 break;
614 }
615 if (i >= legacy_serial_count)
616 goto not_found;
617
618 of_node_put(prom_stdout);
619
620 DBG("Found serial console at ttyS%d\n", offset);
621
622 if (speed) {
623 static char __initdata opt[16];
624 sprintf(opt, "%d", speed);
625 return add_preferred_console("ttyS", offset, opt);
626 } else
627 return add_preferred_console("ttyS", offset, NULL);
628
629 not_found:
630 DBG("No preferred console found !\n");
631 of_node_put(prom_stdout);
632 return -ENODEV;
633}
634console_initcall(check_legacy_serial_console);
635
636#endif /* CONFIG_SERIAL_8250_CONSOLE */