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-rw-r--r--arch/powerpc/kernel/legacy_serial.c557
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 0000000..f970ace
--- /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);
+
generated by cgit v0.10.2 at 2024-11-14 05:57:59 (GMT)