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>
7 #include <linux/of_address.h>
8 #include <linux/of_device.h>
9 #include <linux/serial_reg.h>
13 #include <asm/serial.h>
15 #include <asm/pci-bridge.h>
16 #include <asm/ppc-pci.h>
21 #define DBG(fmt...) do { printk(fmt); } while(0)
23 #define DBG(fmt...) do { } while(0)
26 #define MAX_LEGACY_SERIAL_PORTS 8
28 static struct plat_serial8250_port
29 legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1];
30 static struct legacy_serial_info {
31 struct device_node *np;
36 } legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS];
38 static const struct of_device_id legacy_serial_parents[] __initconst = {
40 {.type = "tsi-bridge",},
42 {.compatible = "ibm,opb",},
43 {.compatible = "simple-bus",},
44 {.compatible = "wrs,epld-localbus",},
48 static unsigned int legacy_serial_count;
49 static int legacy_serial_console = -1;
51 static const upf_t legacy_port_flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
52 UPF_SHARE_IRQ | UPF_FIXED_PORT;
54 static unsigned int tsi_serial_in(struct uart_port *p, int offset)
57 offset = offset << p->regshift;
58 if (offset == UART_IIR) {
59 tmp = readl(p->membase + (UART_IIR & ~3));
60 return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
62 return readb(p->membase + offset);
65 static void tsi_serial_out(struct uart_port *p, int offset, int value)
67 offset = offset << p->regshift;
68 if (!((offset == UART_IER) && (value & UART_IER_UUE)))
69 writeb(value, p->membase + offset);
72 static int __init add_legacy_port(struct device_node *np, int want_index,
73 int iotype, phys_addr_t base,
74 phys_addr_t taddr, unsigned long irq,
75 upf_t flags, int irq_check_parent)
77 const __be32 *clk, *spd, *rs;
78 u32 clock = BASE_BAUD * 16;
82 /* get clock freq. if present */
83 clk = of_get_property(np, "clock-frequency", NULL);
85 clock = be32_to_cpup(clk);
87 /* get default speed if present */
88 spd = of_get_property(np, "current-speed", NULL);
90 /* get register shift if present */
91 rs = of_get_property(np, "reg-shift", NULL);
93 shift = be32_to_cpup(rs);
95 /* If we have a location index, then try to use it */
96 if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS)
99 index = legacy_serial_count;
101 /* if our index is still out of range, that mean that
102 * array is full, we could scan for a free slot but that
103 * make little sense to bother, just skip the port
105 if (index >= MAX_LEGACY_SERIAL_PORTS)
107 if (index >= legacy_serial_count)
108 legacy_serial_count = index + 1;
110 /* Check if there is a port who already claimed our slot */
111 if (legacy_serial_infos[index].np != NULL) {
112 /* if we still have some room, move it, else override */
113 if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) {
114 printk(KERN_DEBUG "Moved legacy port %d -> %d\n",
115 index, legacy_serial_count);
116 legacy_serial_ports[legacy_serial_count] =
117 legacy_serial_ports[index];
118 legacy_serial_infos[legacy_serial_count] =
119 legacy_serial_infos[index];
120 legacy_serial_count++;
122 printk(KERN_DEBUG "Replacing legacy port %d\n", index);
126 /* Now fill the entry */
127 memset(&legacy_serial_ports[index], 0,
128 sizeof(struct plat_serial8250_port));
129 if (iotype == UPIO_PORT)
130 legacy_serial_ports[index].iobase = base;
132 legacy_serial_ports[index].mapbase = base;
134 legacy_serial_ports[index].iotype = iotype;
135 legacy_serial_ports[index].uartclk = clock;
136 legacy_serial_ports[index].irq = irq;
137 legacy_serial_ports[index].flags = flags;
138 legacy_serial_ports[index].regshift = shift;
139 legacy_serial_infos[index].taddr = taddr;
140 legacy_serial_infos[index].np = of_node_get(np);
141 legacy_serial_infos[index].clock = clock;
142 legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0;
143 legacy_serial_infos[index].irq_check_parent = irq_check_parent;
145 if (iotype == UPIO_TSI) {
146 legacy_serial_ports[index].serial_in = tsi_serial_in;
147 legacy_serial_ports[index].serial_out = tsi_serial_out;
150 printk(KERN_DEBUG "Found legacy serial port %d for %s\n",
151 index, np->full_name);
152 printk(KERN_DEBUG " %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n",
153 (iotype == UPIO_PORT) ? "port" : "mem",
154 (unsigned long long)base, (unsigned long long)taddr, irq,
155 legacy_serial_ports[index].uartclk,
156 legacy_serial_infos[index].speed);
161 static int __init add_legacy_soc_port(struct device_node *np,
162 struct device_node *soc_dev)
166 struct device_node *tsi = of_get_parent(np);
168 /* We only support ports that have a clock frequency properly
169 * encoded in the device-tree.
171 if (of_get_property(np, "clock-frequency", NULL) == NULL)
174 /* if reg-offset don't try to use it */
175 if ((of_get_property(np, "reg-offset", NULL) != NULL))
178 /* if rtas uses this device, don't try to use it as well */
179 if (of_get_property(np, "used-by-rtas", NULL) != NULL)
182 /* Get the address */
183 addrp = of_get_address(soc_dev, 0, NULL, NULL);
187 addr = of_translate_address(soc_dev, addrp);
188 if (addr == OF_BAD_ADDR)
191 /* Add port, irq will be dealt with later. We passed a translated
192 * IO port value. It will be fixed up later along with the irq
194 if (tsi && !strcmp(tsi->type, "tsi-bridge"))
195 return add_legacy_port(np, -1, UPIO_TSI, addr, addr,
196 0, legacy_port_flags, 0);
198 return add_legacy_port(np, -1, UPIO_MEM, addr, addr,
199 0, legacy_port_flags, 0);
202 static int __init add_legacy_isa_port(struct device_node *np,
203 struct device_node *isa_brg)
210 DBG(" -> add_legacy_isa_port(%s)\n", np->full_name);
212 /* Get the ISA port number */
213 reg = of_get_property(np, "reg", NULL);
217 /* Verify it's an IO port, we don't support anything else */
218 if (!(be32_to_cpu(reg[0]) & 0x00000001))
221 /* Now look for an "ibm,aix-loc" property that gives us ordering
224 typep = of_get_property(np, "ibm,aix-loc", NULL);
226 /* If we have a location index, then use it */
227 if (typep && *typep == 'S')
228 index = simple_strtol(typep+1, NULL, 0) - 1;
230 /* Translate ISA address. If it fails, we still register the port
231 * with no translated address so that it can be picked up as an IO
232 * port later by the serial driver
234 * Note: Don't even try on P8 lpc, we know it's not directly mapped
236 if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc")) {
237 taddr = of_translate_address(np, reg);
238 if (taddr == OF_BAD_ADDR)
243 /* Add port, irq will be dealt with later */
244 return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]),
245 taddr, 0, legacy_port_flags, 0);
250 static int __init add_legacy_pci_port(struct device_node *np,
251 struct device_node *pci_dev)
256 int iotype, index = -1, lindex = 0;
258 DBG(" -> add_legacy_pci_port(%s)\n", np->full_name);
260 /* We only support ports that have a clock frequency properly
261 * encoded in the device-tree (that is have an fcode). Anything
262 * else can't be used that early and will be normally probed by
263 * the generic 8250_pci driver later on. The reason is that 8250
264 * compatible UARTs on PCI need all sort of quirks (port offsets
265 * etc...) that this code doesn't know about
267 if (of_get_property(np, "clock-frequency", NULL) == NULL)
270 /* Get the PCI address. Assume BAR 0 */
271 addrp = of_get_pci_address(pci_dev, 0, NULL, &flags);
275 /* We only support BAR 0 for now */
276 iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT;
277 addr = of_translate_address(pci_dev, addrp);
278 if (addr == OF_BAD_ADDR)
281 /* Set the IO base to the same as the translated address for MMIO,
282 * or to the domain local IO base for PIO (it will be fixed up later)
284 if (iotype == UPIO_MEM)
287 base = of_read_number(&addrp[2], 1);
289 /* Try to guess an index... If we have subdevices of the pci dev,
290 * we get to their "reg" property
293 const __be32 *reg = of_get_property(np, "reg", NULL);
294 if (reg && (be32_to_cpup(reg) < 4))
295 index = lindex = be32_to_cpup(reg);
298 /* Local index means it's the Nth port in the PCI chip. Unfortunately
299 * the offset to add here is device specific. We know about those
300 * EXAR ports and we default to the most common case. If your UART
301 * doesn't work for these settings, you'll have to add your own special
304 if (of_device_is_compatible(pci_dev, "pci13a8,152") ||
305 of_device_is_compatible(pci_dev, "pci13a8,154") ||
306 of_device_is_compatible(pci_dev, "pci13a8,158")) {
307 addr += 0x200 * lindex;
308 base += 0x200 * lindex;
314 /* Add port, irq will be dealt with later. We passed a translated
315 * IO port value. It will be fixed up later along with the irq
317 return add_legacy_port(np, index, iotype, base, addr, 0,
318 legacy_port_flags, np != pci_dev);
322 static void __init setup_legacy_serial_console(int console)
324 struct legacy_serial_info *info = &legacy_serial_infos[console];
325 struct plat_serial8250_port *port = &legacy_serial_ports[console];
329 stride = 1 << port->regshift;
331 /* Check if a translated MMIO address has been found */
333 addr = ioremap(info->taddr, 0x1000);
336 udbg_uart_init_mmio(addr, stride);
338 /* Check if it's PIO and we support untranslated PIO */
339 if (port->iotype == UPIO_PORT && isa_io_special)
340 udbg_uart_init_pio(port->iobase, stride);
345 /* Try to query the current speed */
346 if (info->speed == 0)
347 info->speed = udbg_probe_uart_speed(info->clock);
350 DBG("default console speed = %d\n", info->speed);
351 udbg_uart_setup(info->speed, info->clock);
355 * This is called very early, as part of setup_system() or eventually
356 * setup_arch(), basically before anything else in this file. This function
357 * will try to build a list of all the available 8250-compatible serial ports
358 * in the machine using the Open Firmware device-tree. It currently only deals
359 * with ISA and PCI busses but could be extended. It allows a very early boot
360 * console to be initialized, that list is also used later to provide 8250 with
361 * the machine non-PCI ports and to properly pick the default console port
363 void __init find_legacy_serial_ports(void)
365 struct device_node *np, *stdout = NULL;
369 DBG(" -> find_legacy_serial_port()\n");
371 /* Now find out if one of these is out firmware console */
372 path = of_get_property(of_chosen, "linux,stdout-path", NULL);
374 stdout = of_find_node_by_path(path);
376 DBG("stdout is %s\n", stdout->full_name);
378 DBG(" no linux,stdout-path !\n");
381 /* Iterate over all the 16550 ports, looking for known parents */
382 for_each_compatible_node(np, "serial", "ns16550") {
383 struct device_node *parent = of_get_parent(np);
386 if (of_match_node(legacy_serial_parents, parent) != NULL) {
387 if (of_device_is_available(np)) {
388 index = add_legacy_soc_port(np, np);
389 if (index >= 0 && np == stdout)
390 legacy_serial_console = index;
396 /* Next, fill our array with ISA ports */
397 for_each_node_by_type(np, "serial") {
398 struct device_node *isa = of_get_parent(np);
399 if (isa && (!strcmp(isa->name, "isa") ||
400 !strcmp(isa->name, "lpc"))) {
401 if (of_device_is_available(np)) {
402 index = add_legacy_isa_port(np, isa);
403 if (index >= 0 && np == stdout)
404 legacy_serial_console = index;
411 /* Next, try to locate PCI ports */
412 for (np = NULL; (np = of_find_all_nodes(np));) {
413 struct device_node *pci, *parent = of_get_parent(np);
414 if (parent && !strcmp(parent->name, "isa")) {
418 if (strcmp(np->name, "serial") && strcmp(np->type, "serial")) {
422 /* Check for known pciclass, and also check whether we have
423 * a device with child nodes for ports or not
425 if (of_device_is_compatible(np, "pciclass,0700") ||
426 of_device_is_compatible(np, "pciclass,070002"))
428 else if (of_device_is_compatible(parent, "pciclass,0700") ||
429 of_device_is_compatible(parent, "pciclass,070002"))
435 index = add_legacy_pci_port(np, pci);
436 if (index >= 0 && np == stdout)
437 legacy_serial_console = index;
442 DBG("legacy_serial_console = %d\n", legacy_serial_console);
443 if (legacy_serial_console >= 0)
444 setup_legacy_serial_console(legacy_serial_console);
445 DBG(" <- find_legacy_serial_port()\n");
448 static struct platform_device serial_device = {
449 .name = "serial8250",
450 .id = PLAT8250_DEV_PLATFORM,
452 .platform_data = legacy_serial_ports,
456 static void __init fixup_port_irq(int index,
457 struct device_node *np,
458 struct plat_serial8250_port *port)
462 DBG("fixup_port_irq(%d)\n", index);
464 virq = irq_of_parse_and_map(np, 0);
465 if (!virq && legacy_serial_infos[index].irq_check_parent) {
466 np = of_get_parent(np);
469 virq = irq_of_parse_and_map(np, 0);
477 #ifdef CONFIG_SERIAL_8250_FSL
478 if (of_device_is_compatible(np, "fsl,ns16550"))
479 port->handle_irq = fsl8250_handle_irq;
483 static void __init fixup_port_pio(int index,
484 struct device_node *np,
485 struct plat_serial8250_port *port)
488 struct pci_controller *hose;
490 DBG("fixup_port_pio(%d)\n", index);
492 hose = pci_find_hose_for_OF_device(np);
494 unsigned long offset = (unsigned long)hose->io_base_virt -
500 DBG("port %d, IO %lx -> %lx\n",
501 index, port->iobase, port->iobase + offset);
502 port->iobase += offset;
507 static void __init fixup_port_mmio(int index,
508 struct device_node *np,
509 struct plat_serial8250_port *port)
511 DBG("fixup_port_mmio(%d)\n", index);
513 port->membase = ioremap(port->mapbase, 0x100);
517 * This is called as an arch initcall, hopefully before the PCI bus is
518 * probed and/or the 8250 driver loaded since we need to register our
519 * platform devices before 8250 PCI ones are detected as some of them
520 * must properly "override" the platform ones.
522 * This function fixes up the interrupt value for platform ports as it
523 * couldn't be done earlier before interrupt maps have been parsed. It
524 * also "corrects" the IO address for PIO ports for the same reason,
525 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then
526 * registers all those platform ports for use by the 8250 driver when it
529 static int __init serial_dev_init(void)
533 if (legacy_serial_count == 0)
537 * Before we register the platform serial devices, we need
538 * to fixup their interrupts and their IO ports.
540 DBG("Fixing serial ports interrupts and IO ports ...\n");
542 for (i = 0; i < legacy_serial_count; i++) {
543 struct plat_serial8250_port *port = &legacy_serial_ports[i];
544 struct device_node *np = legacy_serial_infos[i].np;
547 fixup_port_irq(i, np, port);
548 if (port->iotype == UPIO_PORT)
549 fixup_port_pio(i, np, port);
550 if ((port->iotype == UPIO_MEM) || (port->iotype == UPIO_TSI))
551 fixup_port_mmio(i, np, port);
554 DBG("Registering platform serial ports\n");
556 return platform_device_register(&serial_device);
558 device_initcall(serial_dev_init);
561 #ifdef CONFIG_SERIAL_8250_CONSOLE
563 * This is called very early, as part of console_init() (typically just after
564 * time_init()). This function is respondible for trying to find a good
565 * default console on serial ports. It tries to match the open firmware
566 * default output with one of the available serial console drivers that have
567 * been probed earlier by find_legacy_serial_ports()
569 static int __init check_legacy_serial_console(void)
571 struct device_node *prom_stdout = NULL;
572 int i, speed = 0, offset = 0;
576 DBG(" -> check_legacy_serial_console()\n");
578 /* The user has requested a console so this is already set up. */
579 if (strstr(boot_command_line, "console=")) {
580 DBG(" console was specified !\n");
585 DBG(" of_chosen is NULL !\n");
589 if (legacy_serial_console < 0) {
590 DBG(" legacy_serial_console not found !\n");
593 /* We are getting a weird phandle from OF ... */
594 /* ... So use the full path instead */
595 name = of_get_property(of_chosen, "linux,stdout-path", NULL);
597 DBG(" no linux,stdout-path !\n");
600 prom_stdout = of_find_node_by_path(name);
602 DBG(" can't find stdout package %s !\n", name);
605 DBG("stdout is %s\n", prom_stdout->full_name);
607 name = of_get_property(prom_stdout, "name", NULL);
609 DBG(" stdout package has no name !\n");
612 spd = of_get_property(prom_stdout, "current-speed", NULL);
614 speed = be32_to_cpup(spd);
616 if (strcmp(name, "serial") != 0)
619 /* Look for it in probed array */
620 for (i = 0; i < legacy_serial_count; i++) {
621 if (prom_stdout != legacy_serial_infos[i].np)
624 speed = legacy_serial_infos[i].speed;
627 if (i >= legacy_serial_count)
630 of_node_put(prom_stdout);
632 DBG("Found serial console at ttyS%d\n", offset);
635 static char __initdata opt[16];
636 sprintf(opt, "%d", speed);
637 return add_preferred_console("ttyS", offset, opt);
639 return add_preferred_console("ttyS", offset, NULL);
642 DBG("No preferred console found !\n");
643 of_node_put(prom_stdout);
646 console_initcall(check_legacy_serial_console);
648 #endif /* CONFIG_SERIAL_8250_CONSOLE */