diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | arch/x86/Kconfig.debug | 13 | ||||
| -rw-r--r-- | arch/x86/kernel/early_printk.c | 762 |
3 files changed, 774 insertions, 4 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index e7bea3e85304..92ddd4afe174 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -657,11 +657,12 @@ and is between 256 and 4096 characters. It is defined in the file earlyprintk= [X86-32,X86-64,SH,BLACKFIN] earlyprintk=vga earlyprintk=serial[,ttySn[,baudrate]] + earlyprintk=dbgp Append ",keep" to not disable it when the real console takes over. - Only vga or serial at a time, not both. + Only vga or serial or usb debug port at a time. Currently only ttyS0 and ttyS1 are supported. diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 092f019e033a..93422d2ecf61 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -43,6 +43,19 @@ config EARLY_PRINTK with klogd/syslogd or the X server. You should normally N here, unless you want to debug such a crash. +config EARLY_PRINTK_DBGP + bool "Early printk via EHCI debug port" + default n + depends on EARLY_PRINTK + help + Write kernel log output directly into the EHCI debug port. + + This is useful for kernel debugging when your machine crashes very + early before the console code is initialized. For normal operation + it is not recommended because it looks ugly and doesn't cooperate + with klogd/syslogd or the X server. You should normally N here, + unless you want to debug such a crash. You need usb debug device. + config DEBUG_STACKOVERFLOW bool "Check for stack overflows" depends on DEBUG_KERNEL diff --git a/arch/x86/kernel/early_printk.c b/arch/x86/kernel/early_printk.c index ff9e7350da54..28155acf706e 100644 --- a/arch/x86/kernel/early_printk.c +++ b/arch/x86/kernel/early_printk.c @@ -3,11 +3,19 @@ #include <linux/init.h> #include <linux/string.h> #include <linux/screen_info.h> +#include <linux/usb/ch9.h> +#include <linux/pci_regs.h> +#include <linux/pci_ids.h> +#include <linux/errno.h> #include <asm/io.h> #include <asm/processor.h> #include <asm/fcntl.h> #include <asm/setup.h> #include <xen/hvc-console.h> +#include <asm/pci-direct.h> +#include <asm/pgtable.h> +#include <asm/fixmap.h> +#include <linux/usb/ehci_def.h> /* Simple VGA output */ #define VGABASE (__ISA_IO_base + 0xb8000) @@ -78,6 +86,7 @@ static int early_serial_base = 0x3f8; /* ttyS0 */ static int early_serial_putc(unsigned char ch) { unsigned timeout = 0xffff; + while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) cpu_relax(); outb(ch, early_serial_base + TXR); @@ -151,6 +160,721 @@ static struct console early_serial_console = { .index = -1, }; +#ifdef CONFIG_EARLY_PRINTK_DBGP + +static struct ehci_caps __iomem *ehci_caps; +static struct ehci_regs __iomem *ehci_regs; +static struct ehci_dbg_port __iomem *ehci_debug; +static unsigned int dbgp_endpoint_out; + +struct ehci_dev { + u32 bus; + u32 slot; + u32 func; +}; + +static struct ehci_dev ehci_dev; + +#define USB_DEBUG_DEVNUM 127 + +#define DBGP_DATA_TOGGLE 0x8800 + +static inline u32 dbgp_pid_update(u32 x, u32 tok) +{ + return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff); +} + +static inline u32 dbgp_len_update(u32 x, u32 len) +{ + return (x & ~0x0f) | (len & 0x0f); +} + +/* + * USB Packet IDs (PIDs) + */ + +/* token */ +#define USB_PID_OUT 0xe1 +#define USB_PID_IN 0x69 +#define USB_PID_SOF 0xa5 +#define USB_PID_SETUP 0x2d +/* handshake */ +#define USB_PID_ACK 0xd2 +#define USB_PID_NAK 0x5a +#define USB_PID_STALL 0x1e +#define USB_PID_NYET 0x96 +/* data */ +#define USB_PID_DATA0 0xc3 +#define USB_PID_DATA1 0x4b +#define USB_PID_DATA2 0x87 +#define USB_PID_MDATA 0x0f +/* Special */ +#define USB_PID_PREAMBLE 0x3c +#define USB_PID_ERR 0x3c +#define USB_PID_SPLIT 0x78 +#define USB_PID_PING 0xb4 +#define USB_PID_UNDEF_0 0xf0 + +#define USB_PID_DATA_TOGGLE 0x88 +#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE) + +#define PCI_CAP_ID_EHCI_DEBUG 0xa + +#define HUB_ROOT_RESET_TIME 50 /* times are in msec */ +#define HUB_SHORT_RESET_TIME 10 +#define HUB_LONG_RESET_TIME 200 +#define HUB_RESET_TIMEOUT 500 + +#define DBGP_MAX_PACKET 8 + +static int dbgp_wait_until_complete(void) +{ + u32 ctrl; + int loop = 0x100000; + + do { + ctrl = readl(&ehci_debug->control); + /* Stop when the transaction is finished */ + if (ctrl & DBGP_DONE) + break; + } while (--loop > 0); + + if (!loop) + return -1; + + /* + * Now that we have observed the completed transaction, + * clear the done bit. + */ + writel(ctrl | DBGP_DONE, &ehci_debug->control); + return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl); +} + +static void dbgp_mdelay(int ms) +{ + int i; + + while (ms--) { + for (i = 0; i < 1000; i++) + outb(0x1, 0x80); + } +} + +static void dbgp_breath(void) +{ + /* Sleep to give the debug port a chance to breathe */ +} + +static int dbgp_wait_until_done(unsigned ctrl) +{ + u32 pids, lpid; + int ret; + int loop = 3; + +retry: + writel(ctrl | DBGP_GO, &ehci_debug->control); + ret = dbgp_wait_until_complete(); + pids = readl(&ehci_debug->pids); + lpid = DBGP_PID_GET(pids); + + if (ret < 0) + return ret; + + /* + * If the port is getting full or it has dropped data + * start pacing ourselves, not necessary but it's friendly. + */ + if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET)) + dbgp_breath(); + + /* If I get a NACK reissue the transmission */ + if (lpid == USB_PID_NAK) { + if (--loop > 0) + goto retry; + } + + return ret; +} + +static void dbgp_set_data(const void *buf, int size) +{ + const unsigned char *bytes = buf; + u32 lo, hi; + int i; + + lo = hi = 0; + for (i = 0; i < 4 && i < size; i++) + lo |= bytes[i] << (8*i); + for (; i < 8 && i < size; i++) + hi |= bytes[i] << (8*(i - 4)); + writel(lo, &ehci_debug->data03); + writel(hi, &ehci_debug->data47); +} + +static void dbgp_get_data(void *buf, int size) +{ + unsigned char *bytes = buf; + u32 lo, hi; + int i; + + lo = readl(&ehci_debug->data03); + hi = readl(&ehci_debug->data47); + for (i = 0; i < 4 && i < size; i++) + bytes[i] = (lo >> (8*i)) & 0xff; + for (; i < 8 && i < size; i++) + bytes[i] = (hi >> (8*(i - 4))) & 0xff; +} + +static int dbgp_bulk_write(unsigned devnum, unsigned endpoint, + const char *bytes, int size) +{ + u32 pids, addr, ctrl; + int ret; + + if (size > DBGP_MAX_PACKET) + return -1; + + addr = DBGP_EPADDR(devnum, endpoint); + + pids = readl(&ehci_debug->pids); + pids = dbgp_pid_update(pids, USB_PID_OUT); + + ctrl = readl(&ehci_debug->control); + ctrl = dbgp_len_update(ctrl, size); + ctrl |= DBGP_OUT; + ctrl |= DBGP_GO; + + dbgp_set_data(bytes, size); + writel(addr, &ehci_debug->address); + writel(pids, &ehci_debug->pids); + + ret = dbgp_wait_until_done(ctrl); + if (ret < 0) + return ret; + + return ret; +} + +static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, + int size) +{ + u32 pids, addr, ctrl; + int ret; + + if (size > DBGP_MAX_PACKET) + return -1; + + addr = DBGP_EPADDR(devnum, endpoint); + + pids = readl(&ehci_debug->pids); + pids = dbgp_pid_update(pids, USB_PID_IN); + + ctrl = readl(&ehci_debug->control); + ctrl = dbgp_len_update(ctrl, size); + ctrl &= ~DBGP_OUT; + ctrl |= DBGP_GO; + + writel(addr, &ehci_debug->address); + writel(pids, &ehci_debug->pids); + ret = dbgp_wait_until_done(ctrl); + if (ret < 0) + return ret; + + if (size > ret) + size = ret; + dbgp_get_data(data, size); + return ret; +} + +static int dbgp_control_msg(unsigned devnum, int requesttype, int request, + int value, int index, void *data, int size) +{ + u32 pids, addr, ctrl; + struct usb_ctrlrequest req; + int read; + int ret; + + read = (requesttype & USB_DIR_IN) != 0; + if (size > (read ? DBGP_MAX_PACKET:0)) + return -1; + + /* Compute the control message */ + req.bRequestType = requesttype; + req.bRequest = request; + req.wValue = value; + req.wIndex = index; + req.wLength = size; + + pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP); + addr = DBGP_EPADDR(devnum, 0); + + ctrl = readl(&ehci_debug->control); + ctrl = dbgp_len_update(ctrl, sizeof(req)); + ctrl |= DBGP_OUT; + ctrl |= DBGP_GO; + + /* Send the setup message */ + dbgp_set_data(&req, sizeof(req)); + writel(addr, &ehci_debug->address); + writel(pids, &ehci_debug->pids); + ret = dbgp_wait_until_done(ctrl); + if (ret < 0) + return ret; + + /* Read the result */ + return dbgp_bulk_read(devnum, 0, data, size); +} + + +/* Find a PCI capability */ +static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap) +{ + u8 pos; + int bytes; + + if (!(read_pci_config_16(num, slot, func, PCI_STATUS) & + PCI_STATUS_CAP_LIST)) + return 0; + + pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST); + for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) { + u8 id; + + pos &= ~3; + id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID); + if (id == 0xff) + break; + if (id == cap) + return pos; + + pos = read_pci_config_byte(num, slot, func, + pos+PCI_CAP_LIST_NEXT); + } + return 0; +} + +static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func) +{ + u32 class; + + class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION); + if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI) + return 0; + + return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG); +} + +static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc) +{ + u32 bus, slot, func; + + for (bus = 0; bus < 256; bus++) { + for (slot = 0; slot < 32; slot++) { + for (func = 0; func < 8; func++) { + unsigned cap; + + cap = __find_dbgp(bus, slot, func); + + if (!cap) + continue; + if (ehci_num-- != 0) + continue; + *rbus = bus; + *rslot = slot; + *rfunc = func; + return cap; + } + } + } + return 0; +} + +static int ehci_reset_port(int port) +{ + u32 portsc; + u32 delay_time, delay; + int loop; + + /* Reset the usb debug port */ + portsc = readl(&ehci_regs->port_status[port - 1]); + portsc &= ~PORT_PE; + portsc |= PORT_RESET; + writel(portsc, &ehci_regs->port_status[port - 1]); + + delay = HUB_ROOT_RESET_TIME; + for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT; + delay_time += delay) { + dbgp_mdelay(delay); + + portsc = readl(&ehci_regs->port_status[port - 1]); + if (portsc & PORT_RESET) { + /* force reset to complete */ + loop = 2; + writel(portsc & ~(PORT_RWC_BITS | PORT_RESET), + &ehci_regs->port_status[port - 1]); + do { + portsc = readl(&ehci_regs->port_status[port-1]); + } while ((portsc & PORT_RESET) && (--loop > 0)); + } + + /* Device went away? */ + if (!(portsc & PORT_CONNECT)) + return -ENOTCONN; + + /* bomb out completely if something weird happend */ + if ((portsc & PORT_CSC)) + return -EINVAL; + + /* If we've finished resetting, then break out of the loop */ + if (!(portsc & PORT_RESET) && (portsc & PORT_PE)) + return 0; + } + return -EBUSY; +} + +static int ehci_wait_for_port(int port) +{ + u32 status; + int ret, reps; + + for (reps = 0; reps < 3; reps++) { + dbgp_mdelay(100); + status = readl(&ehci_regs->status); + if (status & STS_PCD) { + ret = ehci_reset_port(port); + if (ret == 0) + return 0; + } + } + return -ENOTCONN; +} + +#ifdef DBGP_DEBUG +# define dbgp_printk early_printk +#else +static inline void dbgp_printk(const char *fmt, ...) { } +#endif + +typedef void (*set_debug_port_t)(int port); + +static void default_set_debug_port(int port) +{ +} + +static set_debug_port_t set_debug_port = default_set_debug_port; + +static void nvidia_set_debug_port(int port) +{ + u32 dword; + dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, + 0x74); + dword &= ~(0x0f<<12); + dword |= ((port & 0x0f)<<12); + write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74, + dword); + dbgp_printk("set debug port to %d\n", port); +} + +static void __init detect_set_debug_port(void) +{ + u32 vendorid; + + vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, + 0x00); + + if ((vendorid & 0xffff) == 0x10de) { + dbgp_printk("using nvidia set_debug_port\n"); + set_debug_port = nvidia_set_debug_port; + } +} + +static int __init ehci_setup(void) +{ + struct usb_debug_descriptor dbgp_desc; + u32 cmd, ctrl, status, portsc, hcs_params; + u32 debug_port, new_debug_port = 0, n_ports; + u32 devnum; + int ret, i; + int loop; + int port_map_tried; + int playtimes = 3; + +try_next_time: + port_map_tried = 0; + +try_next_port: + + hcs_params = readl(&ehci_caps->hcs_params); + debug_port = HCS_DEBUG_PORT(hcs_params); + n_ports = HCS_N_PORTS(hcs_params); + + dbgp_printk("debug_port: %d\n", debug_port); + dbgp_printk("n_ports: %d\n", n_ports); + + for (i = 1; i <= n_ports; i++) { + portsc = readl(&ehci_regs->port_status[i-1]); + dbgp_printk("portstatus%d: %08x\n", i, portsc); + } + + if (port_map_tried && (new_debug_port != debug_port)) { + if (--playtimes) { + set_debug_port(new_debug_port); + goto try_next_time; + } + return -1; + } + + loop = 10; + /* Reset the EHCI controller */ + cmd = readl(&ehci_regs->command); + cmd |= CMD_RESET; + writel(cmd, &ehci_regs->command); + do { + cmd = readl(&ehci_regs->command); + } while ((cmd & CMD_RESET) && (--loop > 0)); + + if (!loop) { + dbgp_printk("can not reset ehci\n"); + return -1; + } + dbgp_printk("ehci reset done\n"); + + /* Claim ownership, but do not enable yet */ + ctrl = readl(&ehci_debug->control); + ctrl |= DBGP_OWNER; + ctrl &= ~(DBGP_ENABLED | DBGP_INUSE); + writel(ctrl, &ehci_debug->control); + + /* Start the ehci running */ + cmd = readl(&ehci_regs->command); + cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET); + cmd |= CMD_RUN; + writel(cmd, &ehci_regs->command); + + /* Ensure everything is routed to the EHCI */ + writel(FLAG_CF, &ehci_regs->configured_flag); + + /* Wait until the controller is no longer halted */ + loop = 10; + do { + status = readl(&ehci_regs->status); + } while ((status & STS_HALT) && (--loop > 0)); + + if (!loop) { + dbgp_printk("ehci can be started\n"); + return -1; + } + dbgp_printk("ehci started\n"); + + /* Wait for a device to show up in the debug port */ + ret = ehci_wait_for_port(debug_port); + if (ret < 0) { + dbgp_printk("No device found in debug port\n"); + goto next_debug_port; + } + dbgp_printk("ehci wait for port done\n"); + + /* Enable the debug port */ + ctrl = readl(&ehci_debug->control); + ctrl |= DBGP_CLAIM; + writel(ctrl, &ehci_debug->control); + ctrl = readl(&ehci_debug->control); + if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) { + dbgp_printk("No device in debug port\n"); + writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control); + goto err; + } + dbgp_printk("debug ported enabled\n"); + + /* Completely transfer the debug device to the debug controller */ + portsc = readl(&ehci_regs->port_status[debug_port - 1]); + portsc &= ~PORT_PE; + writel(portsc, &ehci_regs->port_status[debug_port - 1]); + + dbgp_mdelay(100); + + /* Find the debug device and make it device number 127 */ + for (devnum = 0; devnum <= 127; devnum++) { + ret = dbgp_control_msg(devnum, + USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE, + USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0, + &dbgp_desc, sizeof(dbgp_desc)); + if (ret > 0) + break; + } + if (devnum > 127) { + dbgp_printk("Could not find attached debug device\n"); + goto err; + } + if (ret < 0) { + dbgp_printk("Attached device is not a debug device\n"); + goto err; + } + dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint; + + /* Move the device to 127 if it isn't already there */ + if (devnum != USB_DEBUG_DEVNUM) { + ret = dbgp_control_msg(devnum, + USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, + USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0); + if (ret < 0) { + dbgp_printk("Could not move attached device to %d\n", + USB_DEBUG_DEVNUM); + goto err; + } + devnum = USB_DEBUG_DEVNUM; + dbgp_printk("debug device renamed to 127\n"); + } + + /* Enable the debug interface */ + ret = dbgp_control_msg(USB_DEBUG_DEVNUM, + USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, + USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0); + if (ret < 0) { + dbgp_printk(" Could not enable the debug device\n"); + goto err; + } + dbgp_printk("debug interface enabled\n"); + + /* Perform a small write to get the even/odd data state in sync + */ + ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1); + if (ret < 0) { + dbgp_printk("dbgp_bulk_write failed: %d\n", ret); + goto err; + } + dbgp_printk("small write doned\n"); + + return 0; +err: + /* Things didn't work so remove my claim */ + ctrl = readl(&ehci_debug->control); + ctrl &= ~(DBGP_CLAIM | DBGP_OUT); + writel(ctrl, &ehci_debug->control); + return -1; + +next_debug_port: + port_map_tried |= (1<<(debug_port - 1)); + new_debug_port = ((debug_port-1+1)%n_ports) + 1; + if (port_map_tried != ((1<<n_ports) - 1)) { + set_debug_port(new_debug_port); + goto try_next_port; + } + if (--playtimes) { + set_debug_port(new_debug_port); + goto try_next_time; + } + + return -1; +} + +static int __init early_dbgp_init(char *s) +{ + u32 debug_port, bar, offset; + u32 bus, slot, func, cap; + void __iomem *ehci_bar; + u32 dbgp_num; + u32 bar_val; + char *e; + int ret; + u8 byte; + + if (!early_pci_allowed()) + return -1; + + dbgp_num = 0; + if (*s) + dbgp_num = simple_strtoul(s, &e, 10); + dbgp_printk("dbgp_num: %d\n", dbgp_num); + + cap = find_dbgp(dbgp_num, &bus, &slot, &func); + if (!cap) + return -1; + + dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot, + func); + + debug_port = read_pci_config(bus, slot, func, cap); + bar = (debug_port >> 29) & 0x7; + bar = (bar * 4) + 0xc; + offset = (debug_port >> 16) & 0xfff; + dbgp_printk("bar: %02x offset: %03x\n", bar, offset); + if (bar != PCI_BASE_ADDRESS_0) { + dbgp_printk("only debug ports on bar 1 handled.\n"); + + return -1; + } + + bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0); + dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset); + if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) { + dbgp_printk("only simple 32bit mmio bars supported\n"); + + return -1; + } + + /* double check if the mem space is enabled */ + byte = read_pci_config_byte(bus, slot, func, 0x04); + if (!(byte & 0x2)) { + byte |= 0x02; + write_pci_config_byte(bus, slot, func, 0x04, byte); + dbgp_printk("mmio for ehci enabled\n"); + } + + /* + * FIXME I don't have the bar size so just guess PAGE_SIZE is more + * than enough. 1K is the biggest I have seen. + */ + set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK); + ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE); + ehci_bar += bar_val & ~PAGE_MASK; + dbgp_printk("ehci_bar: %p\n", ehci_bar); + + ehci_caps = ehci_bar; + ehci_regs = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase)); + ehci_debug = ehci_bar + offset; + ehci_dev.bus = bus; + ehci_dev.slot = slot; + ehci_dev.func = func; + + detect_set_debug_port(); + + ret = ehci_setup(); + if (ret < 0) { + dbgp_printk("ehci_setup failed\n"); + ehci_debug = 0; + + return -1; + } + + return 0; +} + +static void early_dbgp_write(struct console *con, const char *str, u32 n) +{ + int chunk, ret; + + if (!ehci_debug) + return; + while (n > 0) { + chunk = n; + if (chunk > DBGP_MAX_PACKET) + chunk = DBGP_MAX_PACKET; + ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, + dbgp_endpoint_out, str, chunk); + str += chunk; + n -= chunk; + } +} + +static struct console early_dbgp_console = { + .name = "earlydbg", + .write = early_dbgp_write, + .flags = CON_PRINTBUFFER, + .index = -1, +}; +#endif + /* Console interface to a host file on AMD's SimNow! */ static int simnow_fd; @@ -165,6 +889,7 @@ enum { static noinline long simnow(long cmd, long a, long b, long c) { long ret; + asm volatile("cpuid" : "=a" (ret) : "b" (a), "c" (b), "d" (c), "0" (MAGIC1), "D" (cmd + MAGIC2)); @@ -174,6 +899,7 @@ static noinline long simnow(long cmd, long a, long b, long c) static void __init simnow_init(char *str) { char *fn = "klog"; + if (*str == '=') fn = ++str; /* error ignored */ @@ -208,10 +934,11 @@ asmlinkage void early_printk(const char *fmt, ...) va_end(ap); } -static int __initdata keep_early; static int __init setup_early_printk(char *buf) { + int keep_early; + if (!buf) return 0; @@ -219,8 +946,7 @@ static int __init setup_early_printk(char *buf) return 0; early_console_initialized = 1; - if (strstr(buf, "keep")) - keep_early = 1; + keep_early = (strstr(buf, "keep") != NULL); if (!strncmp(buf, "serial", 6)) { early_serial_init(buf + 6); @@ -238,6 +964,17 @@ static int __init setup_early_printk(char *buf) simnow_init(buf + 6); early_console = &simnow_console; keep_early = 1; +#ifdef CONFIG_EARLY_PRINTK_DBGP + } else if (!strncmp(buf, "dbgp", 4)) { + if (early_dbgp_init(buf+4) < 0) + return 0; + early_console = &early_dbgp_console; + /* + * usb subsys will reset ehci controller, so don't keep + * that early console + */ + keep_early = 0; +#endif #ifdef CONFIG_HVC_XEN } else if (!strncmp(buf, "xen", 3)) { early_console = &xenboot_console; @@ -251,4 +988,23 @@ static int __init setup_early_printk(char *buf) register_console(early_console); return 0; } + +void __init enable_debug_console(char *buf) +{ +#ifdef DBGP_DEBUG + struct console *old_early_console = NULL; + + if (early_console_initialized && early_console) { + old_early_console = early_console; + unregister_console(early_console); + early_console_initialized = 0; + } + + setup_early_printk(buf); + + if (early_console == old_early_console && old_early_console) + register_console(old_early_console); +#endif +} + early_param("earlyprintk", setup_early_printk); |