diff options
Diffstat (limited to 'arch/powerpc/kernel/legacy_serial.c')
| -rw-r--r-- | arch/powerpc/kernel/legacy_serial.c | 557 |
1 files changed, 557 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c new file mode 100644 index 00000000000000..f970ace208d348 --- /dev/null +++ b/arch/powerpc/kernel/legacy_serial.c @@ -0,0 +1,557 @@ +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/serial.h> +#include <linux/serial_8250.h> +#include <linux/serial_core.h> +#include <linux/console.h> +#include <linux/pci.h> +#include <asm/io.h> +#include <asm/mmu.h> +#include <asm/prom.h> +#include <asm/serial.h> +#include <asm/udbg.h> +#include <asm/pci-bridge.h> +#include <asm/ppc-pci.h> + +#undef DEBUG + +#ifdef DEBUG +#define DBG(fmt...) do { printk(fmt); } while(0) +#else +#define DBG(fmt...) do { } while(0) +#endif + +#define MAX_LEGACY_SERIAL_PORTS 8 + +static struct plat_serial8250_port +legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1]; +static struct legacy_serial_info { + struct device_node *np; + unsigned int speed; + unsigned int clock; + phys_addr_t taddr; +} legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS]; +static unsigned int legacy_serial_count; +static int legacy_serial_console = -1; + +static int __init add_legacy_port(struct device_node *np, int want_index, + int iotype, phys_addr_t base, + phys_addr_t taddr, unsigned long irq, + unsigned int flags) +{ + u32 *clk, *spd, clock = BASE_BAUD * 16; + int index; + + /* get clock freq. if present */ + clk = (u32 *)get_property(np, "clock-frequency", NULL); + if (clk && *clk) + clock = *clk; + + /* get default speed if present */ + spd = (u32 *)get_property(np, "current-speed", NULL); + + /* If we have a location index, then try to use it */ + if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS) + index = want_index; + else + index = legacy_serial_count; + + /* if our index is still out of range, that mean that + * array is full, we could scan for a free slot but that + * make little sense to bother, just skip the port + */ + if (index >= MAX_LEGACY_SERIAL_PORTS) + return -1; + if (index >= legacy_serial_count) + legacy_serial_count = index + 1; + + /* Check if there is a port who already claimed our slot */ + if (legacy_serial_infos[index].np != 0) { + /* if we still have some room, move it, else override */ + if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) { + printk(KERN_INFO "Moved legacy port %d -> %d\n", + index, legacy_serial_count); + legacy_serial_ports[legacy_serial_count] = + legacy_serial_ports[index]; + legacy_serial_infos[legacy_serial_count] = + legacy_serial_infos[index]; + legacy_serial_count++; + } else { + printk(KERN_INFO "Replacing legacy port %d\n", index); + } + } + + /* Now fill the entry */ + memset(&legacy_serial_ports[index], 0, + sizeof(struct plat_serial8250_port)); + if (iotype == UPIO_PORT) + legacy_serial_ports[index].iobase = base; + else + legacy_serial_ports[index].mapbase = base; + legacy_serial_ports[index].iotype = iotype; + legacy_serial_ports[index].uartclk = clock; + legacy_serial_ports[index].irq = irq; + legacy_serial_ports[index].flags = flags; + legacy_serial_infos[index].taddr = taddr; + legacy_serial_infos[index].np = of_node_get(np); + legacy_serial_infos[index].clock = clock; + legacy_serial_infos[index].speed = spd ? *spd : 0; + + printk(KERN_INFO "Found legacy serial port %d for %s\n", + index, np->full_name); + printk(KERN_INFO " %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n", + (iotype == UPIO_PORT) ? "port" : "mem", + (unsigned long long)base, (unsigned long long)taddr, irq, + legacy_serial_ports[index].uartclk, + legacy_serial_infos[index].speed); + + return index; +} + +static int __init add_legacy_soc_port(struct device_node *np, + struct device_node *soc_dev) +{ + phys_addr_t addr; + u32 *addrp; + unsigned int flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST | UPF_SHARE_IRQ; + + /* We only support ports that have a clock frequency properly + * encoded in the device-tree. + */ + if (get_property(np, "clock-frequency", NULL) == NULL) + return -1; + + /* Get the address */ + addrp = of_get_address(soc_dev, 0, NULL, NULL); + if (addrp == NULL) + return -1; + + addr = of_translate_address(soc_dev, addrp); + + /* Add port, irq will be dealt with later. We passed a translated + * IO port value. It will be fixed up later along with the irq + */ + return add_legacy_port(np, -1, UPIO_MEM, addr, addr, NO_IRQ, flags); +} + +#ifdef CONFIG_ISA +static int __init add_legacy_isa_port(struct device_node *np, + struct device_node *isa_brg) +{ + u32 *reg; + char *typep; + int index = -1; + phys_addr_t taddr; + + /* Get the ISA port number */ + reg = (u32 *)get_property(np, "reg", NULL); + if (reg == NULL) + return -1; + + /* Verify it's an IO port, we don't support anything else */ + if (!(reg[0] & 0x00000001)) + return -1; + + /* Now look for an "ibm,aix-loc" property that gives us ordering + * if any... + */ + typep = (char *)get_property(np, "ibm,aix-loc", NULL); + + /* If we have a location index, then use it */ + if (typep && *typep == 'S') + index = simple_strtol(typep+1, NULL, 0) - 1; + + /* Translate ISA address */ + taddr = of_translate_address(np, reg); + + /* Add port, irq will be dealt with later */ + return add_legacy_port(np, index, UPIO_PORT, reg[1], taddr, NO_IRQ, UPF_BOOT_AUTOCONF); + +} +#endif + +#ifdef CONFIG_PCI +static int __init add_legacy_pci_port(struct device_node *np, + struct device_node *pci_dev) +{ + phys_addr_t addr, base; + u32 *addrp; + unsigned int flags; + int iotype, index = -1, lindex = 0; + + /* We only support ports that have a clock frequency properly + * encoded in the device-tree (that is have an fcode). Anything + * else can't be used that early and will be normally probed by + * the generic 8250_pci driver later on. The reason is that 8250 + * compatible UARTs on PCI need all sort of quirks (port offsets + * etc...) that this code doesn't know about + */ + if (get_property(np, "clock-frequency", NULL) == NULL) + return -1; + + /* Get the PCI address. Assume BAR 0 */ + addrp = of_get_pci_address(pci_dev, 0, NULL, &flags); + if (addrp == NULL) + return -1; + + /* We only support BAR 0 for now */ + iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT; + addr = of_translate_address(pci_dev, addrp); + + /* Set the IO base to the same as the translated address for MMIO, + * or to the domain local IO base for PIO (it will be fixed up later) + */ + if (iotype == UPIO_MEM) + base = addr; + else + base = addrp[2]; + + /* Try to guess an index... If we have subdevices of the pci dev, + * we get to their "reg" property + */ + if (np != pci_dev) { + u32 *reg = (u32 *)get_property(np, "reg", NULL); + if (reg && (*reg < 4)) + index = lindex = *reg; + } + + /* Local index means it's the Nth port in the PCI chip. Unfortunately + * the offset to add here is device specific. We know about those + * EXAR ports and we default to the most common case. If your UART + * doesn't work for these settings, you'll have to add your own special + * cases here + */ + if (device_is_compatible(pci_dev, "pci13a8,152") || + device_is_compatible(pci_dev, "pci13a8,154") || + device_is_compatible(pci_dev, "pci13a8,158")) { + addr += 0x200 * lindex; + base += 0x200 * lindex; + } else { + addr += 8 * lindex; + base += 8 * lindex; + } + + /* Add port, irq will be dealt with later. We passed a translated + * IO port value. It will be fixed up later along with the irq + */ + return add_legacy_port(np, index, iotype, base, addr, NO_IRQ, UPF_BOOT_AUTOCONF); +} +#endif + +/* + * This is called very early, as part of setup_system() or eventually + * setup_arch(), basically before anything else in this file. This function + * will try to build a list of all the available 8250-compatible serial ports + * in the machine using the Open Firmware device-tree. It currently only deals + * with ISA and PCI busses but could be extended. It allows a very early boot + * console to be initialized, that list is also used later to provide 8250 with + * the machine non-PCI ports and to properly pick the default console port + */ +void __init find_legacy_serial_ports(void) +{ + struct device_node *np, *stdout = NULL; + char *path; + int index; + + DBG(" -> find_legacy_serial_port()\n"); + + /* Now find out if one of these is out firmware console */ + path = (char *)get_property(of_chosen, "linux,stdout-path", NULL); + if (path != NULL) { + stdout = of_find_node_by_path(path); + if (stdout) + DBG("stdout is %s\n", stdout->full_name); + } else { + DBG(" no linux,stdout-path !\n"); + } + + /* First fill our array with SOC ports */ + for (np = NULL; (np = of_find_compatible_node(np, "serial", "ns16550")) != NULL;) { + struct device_node *soc = of_get_parent(np); + if (soc && !strcmp(soc->type, "soc")) { + index = add_legacy_soc_port(np, np); + if (index >= 0 && np == stdout) + legacy_serial_console = index; + } + of_node_put(soc); + } + +#ifdef CONFIG_ISA + /* First fill our array with ISA ports */ + for (np = NULL; (np = of_find_node_by_type(np, "serial"));) { + struct device_node *isa = of_get_parent(np); + if (isa && !strcmp(isa->name, "isa")) { + index = add_legacy_isa_port(np, isa); + if (index >= 0 && np == stdout) + legacy_serial_console = index; + } + of_node_put(isa); + } +#endif + +#ifdef CONFIG_PCI + /* Next, try to locate PCI ports */ + for (np = NULL; (np = of_find_all_nodes(np));) { + struct device_node *pci, *parent = of_get_parent(np); + if (parent && !strcmp(parent->name, "isa")) { + of_node_put(parent); + continue; + } + if (strcmp(np->name, "serial") && strcmp(np->type, "serial")) { + of_node_put(parent); + continue; + } + /* Check for known pciclass, and also check wether we have + * a device with child nodes for ports or not + */ + if (device_is_compatible(np, "pciclass,0700") || + device_is_compatible(np, "pciclass,070002")) + pci = np; + else if (device_is_compatible(parent, "pciclass,0700") || + device_is_compatible(parent, "pciclass,070002")) + pci = parent; + else { + of_node_put(parent); + continue; + } + index = add_legacy_pci_port(np, pci); + if (index >= 0 && np == stdout) + legacy_serial_console = index; + of_node_put(parent); + } +#endif + + DBG("legacy_serial_console = %d\n", legacy_serial_console); + + /* udbg is 64 bits only for now, that will change soon though ... */ + while (legacy_serial_console >= 0) { + struct legacy_serial_info *info = + &legacy_serial_infos[legacy_serial_console]; + void __iomem *addr; + + if (info->taddr == 0) + break; + addr = ioremap(info->taddr, 0x1000); + if (addr == NULL) + break; + if (info->speed == 0) + info->speed = udbg_probe_uart_speed(addr, info->clock); + DBG("default console speed = %d\n", info->speed); + udbg_init_uart(addr, info->speed, info->clock); + break; + } + + DBG(" <- find_legacy_serial_port()\n"); +} + +static struct platform_device serial_device = { + .name = "serial8250", + .id = PLAT8250_DEV_PLATFORM, + .dev = { + .platform_data = legacy_serial_ports, + }, +}; + +static void __init fixup_port_irq(int index, + struct device_node *np, + struct plat_serial8250_port *port) +{ + DBG("fixup_port_irq(%d)\n", index); + + /* Check for interrupts in that node */ + if (np->n_intrs > 0) { + port->irq = np->intrs[0].line; + DBG(" port %d (%s), irq=%d\n", + index, np->full_name, port->irq); + return; + } + + /* Check for interrupts in the parent */ + np = of_get_parent(np); + if (np == NULL) + return; + + if (np->n_intrs > 0) { + port->irq = np->intrs[0].line; + DBG(" port %d (%s), irq=%d\n", + index, np->full_name, port->irq); + } + of_node_put(np); +} + +static void __init fixup_port_pio(int index, + struct device_node *np, + struct plat_serial8250_port *port) +{ +#ifdef CONFIG_PCI + struct pci_controller *hose; + + DBG("fixup_port_pio(%d)\n", index); + + hose = pci_find_hose_for_OF_device(np); + if (hose) { + unsigned long offset = (unsigned long)hose->io_base_virt - +#ifdef CONFIG_PPC64 + pci_io_base; +#else + isa_io_base; +#endif + DBG("port %d, IO %lx -> %lx\n", + index, port->iobase, port->iobase + offset); + port->iobase += offset; + } +#endif +} + +static void __init fixup_port_mmio(int index, + struct device_node *np, + struct plat_serial8250_port *port) +{ + DBG("fixup_port_mmio(%d)\n", index); + + port->membase = ioremap(port->mapbase, 0x100); +} + +/* + * This is called as an arch initcall, hopefully before the PCI bus is + * probed and/or the 8250 driver loaded since we need to register our + * platform devices before 8250 PCI ones are detected as some of them + * must properly "override" the platform ones. + * + * This function fixes up the interrupt value for platform ports as it + * couldn't be done earlier before interrupt maps have been parsed. It + * also "corrects" the IO address for PIO ports for the same reason, + * since earlier, the PHBs virtual IO space wasn't assigned yet. It then + * registers all those platform ports for use by the 8250 driver when it + * finally loads. + */ +static int __init serial_dev_init(void) +{ + int i; + + if (legacy_serial_count == 0) + return -ENODEV; + + /* + * Before we register the platfrom serial devices, we need + * to fixup their interrutps and their IO ports. + */ + DBG("Fixing serial ports interrupts and IO ports ...\n"); + + for (i = 0; i < legacy_serial_count; i++) { + struct plat_serial8250_port *port = &legacy_serial_ports[i]; + struct device_node *np = legacy_serial_infos[i].np; + + if (port->irq == NO_IRQ) + fixup_port_irq(i, np, port); + if (port->iotype == UPIO_PORT) + fixup_port_pio(i, np, port); + if (port->iotype == UPIO_MEM) + fixup_port_mmio(i, np, port); + } + + DBG("Registering platform serial ports\n"); + + return platform_device_register(&serial_device); +} +arch_initcall(serial_dev_init); + + +/* + * This is called very early, as part of console_init() (typically just after + * time_init()). This function is respondible for trying to find a good + * default console on serial ports. It tries to match the open firmware + * default output with one of the available serial console drivers, either + * one of the platform serial ports that have been probed earlier by + * find_legacy_serial_ports() or some more platform specific ones. + */ +static int __init check_legacy_serial_console(void) +{ + struct device_node *prom_stdout = NULL; + int speed = 0, offset = 0; + char *name; + u32 *spd; + + DBG(" -> check_legacy_serial_console()\n"); + + /* The user has requested a console so this is already set up. */ + if (strstr(saved_command_line, "console=")) { + DBG(" console was specified !\n"); + return -EBUSY; + } + + if (!of_chosen) { + DBG(" of_chosen is NULL !\n"); + return -ENODEV; + } + + if (legacy_serial_console < 0) { + DBG(" legacy_serial_console not found !\n"); + return -ENODEV; + } + /* We are getting a weird phandle from OF ... */ + /* ... So use the full path instead */ + name = (char *)get_property(of_chosen, "linux,stdout-path", NULL); + if (name == NULL) { + DBG(" no linux,stdout-path !\n"); + return -ENODEV; + } + prom_stdout = of_find_node_by_path(name); + if (!prom_stdout) { + DBG(" can't find stdout package %s !\n", name); + return -ENODEV; + } + DBG("stdout is %s\n", prom_stdout->full_name); + + name = (char *)get_property(prom_stdout, "name", NULL); + if (!name) { + DBG(" stdout package has no name !\n"); + goto not_found; + } + spd = (u32 *)get_property(prom_stdout, "current-speed", NULL); + if (spd) + speed = *spd; + + if (0) + ; +#ifdef CONFIG_SERIAL_8250_CONSOLE + else if (strcmp(name, "serial") == 0) { + int i; + /* Look for it in probed array */ + for (i = 0; i < legacy_serial_count; i++) { + if (prom_stdout != legacy_serial_infos[i].np) + continue; + offset = i; + speed = legacy_serial_infos[i].speed; + break; + } + if (i >= legacy_serial_count) + goto not_found; + } +#endif /* CONFIG_SERIAL_8250_CONSOLE */ +#ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE + else if (strcmp(name, "ch-a") == 0) + offset = 0; + else if (strcmp(name, "ch-b") == 0) + offset = 1; +#endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */ + else + goto not_found; + of_node_put(prom_stdout); + + DBG("Found serial console at ttyS%d\n", offset); + + if (speed) { + static char __initdata opt[16]; + sprintf(opt, "%d", speed); + return add_preferred_console("ttyS", offset, opt); + } else + return add_preferred_console("ttyS", offset, NULL); + + not_found: + DBG("No preferred console found !\n"); + of_node_put(prom_stdout); + return -ENODEV; +} +console_initcall(check_legacy_serial_console); + |