diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c index 6198ebded3a4..06e05ea17871 100644 --- a/drivers/usb/early/ehci-dbgp.c +++ b/drivers/usb/early/ehci-dbgp.c @@ -1,5 +1,19 @@ +/* + * Standalone EHCI usb debug driver + * + * Originally written by: + * Eric W. Biederman" and + * Yinghai Lu + * + * Changes for early/late printk and HW errata: + * Jason Wessel + * Copyright (C) 2009 Wind River Systems, Inc. + * + */ + #include #include +#include #include #include #include @@ -9,15 +23,37 @@ #include #include -#ifdef DBGP_DEBUG -# define dbgp_printk printk -#else -static inline void dbgp_printk(const char *fmt, ...) { } -#endif +/* The code here is intended to talk directly to the EHCI debug port + * and does not require that you have any kind of USB host controller + * drivers or USB device drivers compiled into the kernel. + * + * If you make a change to anything in here, the following test cases + * need to pass where a USB debug device works in the following + * configurations. + * + * 1. boot args: earlyprintk=dbgp + * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set + * o kernel compiled with CONFIG_USB_EHCI_HCD=y + * 2. boot args: earlyprintk=dbgp,keep + * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set + * o kernel compiled with CONFIG_USB_EHCI_HCD=y + * 3. boot args: earlyprintk=dbgp console=ttyUSB0 + * o kernel has CONFIG_USB_EHCI_HCD=y and + * CONFIG_USB_SERIAL_DEBUG=y + * 4. boot args: earlyprintk=vga,dbgp + * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set + * o kernel compiled with CONFIG_USB_EHCI_HCD=y + * + * For the 4th configuration you can turn on or off the DBGP_DEBUG + * such that you can debug the dbgp device's driver code. + */ + +static int dbgp_phys_port = 1; static struct ehci_caps __iomem *ehci_caps; static struct ehci_regs __iomem *ehci_regs; static struct ehci_dbg_port __iomem *ehci_debug; +static int dbgp_not_safe; /* Cannot use debug device during ehci reset */ static unsigned int dbgp_endpoint_out; struct ehci_dev { @@ -32,6 +68,26 @@ static struct ehci_dev ehci_dev; #define DBGP_DATA_TOGGLE 0x8800 +#ifdef DBGP_DEBUG +#define dbgp_printk printk +static void dbgp_ehci_status(char *str) +{ + if (!ehci_debug) + return; + dbgp_printk("dbgp: %s\n", str); + dbgp_printk(" Debug control: %08x", readl(&ehci_debug->control)); + dbgp_printk(" ehci cmd : %08x", readl(&ehci_regs->command)); + dbgp_printk(" ehci conf flg: %08x\n", + readl(&ehci_regs->configured_flag)); + dbgp_printk(" ehci status : %08x", readl(&ehci_regs->status)); + dbgp_printk(" ehci portsc : %08x\n", + readl(&ehci_regs->port_status[dbgp_phys_port - 1])); +} +#else +static inline void dbgp_ehci_status(char *str) { } +static inline void dbgp_printk(const char *fmt, ...) { } +#endif + static inline u32 dbgp_pid_update(u32 x, u32 tok) { return ((x ^ DBGP_DATA_TOGGLE) & 0xffff00) | (tok & 0xff); @@ -79,21 +135,23 @@ static inline u32 dbgp_len_update(u32 x, u32 len) #define HUB_RESET_TIMEOUT 500 #define DBGP_MAX_PACKET 8 +#define DBGP_TIMEOUT (250 * 1000) static int dbgp_wait_until_complete(void) { u32 ctrl; - int loop = 0x100000; + int loop = DBGP_TIMEOUT; do { ctrl = readl(&ehci_debug->control); /* Stop when the transaction is finished */ if (ctrl & DBGP_DONE) break; + udelay(1); } while (--loop > 0); if (!loop) - return -1; + return -DBGP_TIMEOUT; /* * Now that we have observed the completed transaction, @@ -103,7 +161,7 @@ static int dbgp_wait_until_complete(void) return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl); } -static void __init dbgp_mdelay(int ms) +static inline void dbgp_mdelay(int ms) { int i; @@ -130,8 +188,17 @@ retry: pids = readl(&ehci_debug->pids); lpid = DBGP_PID_GET(pids); - if (ret < 0) + if (ret < 0) { + /* A -DBGP_TIMEOUT failure here means the device has + * failed, perhaps because it was unplugged, in which + * case we do not want to hang the system so the dbgp + * will be marked as unsafe to use. EHCI reset is the + * only way to recover if you unplug the dbgp device. + */ + if (ret == -DBGP_TIMEOUT && !dbgp_not_safe) + dbgp_not_safe = 1; return ret; + } /* * If the port is getting full or it has dropped data @@ -149,7 +216,7 @@ retry: return ret; } -static void dbgp_set_data(const void *buf, int size) +static inline void dbgp_set_data(const void *buf, int size) { const unsigned char *bytes = buf; u32 lo, hi; @@ -164,7 +231,7 @@ static void dbgp_set_data(const void *buf, int size) writel(hi, &ehci_debug->data47); } -static void __init dbgp_get_data(void *buf, int size) +static inline void dbgp_get_data(void *buf, int size) { unsigned char *bytes = buf; u32 lo, hi; @@ -208,7 +275,7 @@ static int dbgp_bulk_write(unsigned devnum, unsigned endpoint, return ret; } -static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, +static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, int size) { u32 pids, addr, ctrl; @@ -239,7 +306,7 @@ static int __init dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, return ret; } -static int __init dbgp_control_msg(unsigned devnum, int requesttype, +static int dbgp_control_msg(unsigned devnum, int requesttype, int request, int value, int index, void *data, int size) { u32 pids, addr, ctrl; @@ -342,13 +409,179 @@ static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc) return 0; } +static int dbgp_ehci_startup(void) +{ + u32 ctrl, cmd, status; + int loop; + + /* 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); + udelay(1); + + dbgp_ehci_status("EHCI startup"); + /* 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); + if (!(status & STS_HALT)) + break; + udelay(1); + } while (--loop > 0); + + if (!loop) { + dbgp_printk("ehci can not be started\n"); + return -ENODEV; + } + dbgp_printk("ehci started\n"); + return 0; +} + +static int dbgp_ehci_controller_reset(void) +{ + int loop = 250 * 1000; + u32 cmd; + + /* 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_ehci_status("ehci reset done"); + return 0; +} +static int ehci_wait_for_port(int port); +/* Return 0 on success + * Return -ENODEV for any general failure + * Return -EIO if wait for port fails + */ +int dbgp_external_startup(void) +{ + int devnum; + struct usb_debug_descriptor dbgp_desc; + int ret; + u32 ctrl, portsc; + int dbg_port = dbgp_phys_port; + int tries = 3; + + ret = dbgp_ehci_startup(); + if (ret) + return ret; + + /* Wait for a device to show up in the debug port */ + ret = ehci_wait_for_port(dbg_port); + if (ret < 0) { + portsc = readl(&ehci_regs->port_status[dbg_port - 1]); + dbgp_printk("No device found in debug port\n"); + return -EIO; + } + dbgp_ehci_status("wait for port done"); + + /* 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); + return -ENODEV; + } + dbgp_ehci_status("debug ported enabled"); + + /* Completely transfer the debug device to the debug controller */ + portsc = readl(&ehci_regs->port_status[dbg_port - 1]); + portsc &= ~PORT_PE; + writel(portsc, &ehci_regs->port_status[dbg_port - 1]); + + dbgp_mdelay(100); + +try_again: + /* 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"); + dbgp_not_safe = 0; + + return 0; +err: + if (tries--) + goto try_again; + return -ENODEV; +} +EXPORT_SYMBOL_GPL(dbgp_external_startup); + static int __init ehci_reset_port(int port) { u32 portsc; u32 delay_time, delay; int loop; - dbgp_printk("ehci_reset_port %i\n", port); + dbgp_ehci_status("reset port"); /* Reset the usb debug port */ portsc = readl(&ehci_regs->port_status[port - 1]); portsc &= ~PORT_PE; @@ -388,7 +621,7 @@ static int __init ehci_reset_port(int port) return -EBUSY; } -static int __init ehci_wait_for_port(int port) +static int ehci_wait_for_port(int port) { u32 status; int ret, reps; @@ -487,12 +720,9 @@ static void __init early_ehci_bios_handoff(void) static int __init ehci_setup(void) { - struct usb_debug_descriptor dbgp_desc; - u32 cmd, ctrl, status, portsc, hcs_params; + u32 ctrl, 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; @@ -505,10 +735,12 @@ try_next_port: hcs_params = readl(&ehci_caps->hcs_params); debug_port = HCS_DEBUG_PORT(hcs_params); + dbgp_phys_port = debug_port; n_ports = HCS_N_PORTS(hcs_params); dbgp_printk("debug_port: %d\n", debug_port); dbgp_printk("n_ports: %d\n", n_ports); + dbgp_ehci_status(""); for (i = 1; i <= n_ports; i++) { portsc = readl(&ehci_regs->port_status[i-1]); @@ -523,138 +755,27 @@ try_next_port: return -1; } - loop = 250 * 1000; - /* 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; + /* Only reset the controller if it is not already in the + * configured state */ + if (!(readl(&ehci_regs->configured_flag) & FLAG_CF)) { + if (dbgp_ehci_controller_reset() != 0) + return -1; + } else { + dbgp_ehci_status("ehci skip - already configured"); } - 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); - udelay(1); - - /* 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); - if (!(status & STS_HALT)) - break; - udelay(1); - } while (--loop > 0); - - if (!loop) { - dbgp_printk("ehci can not 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"); + ret = dbgp_external_startup(); + if (ret == -EIO) 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; + /* 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; } - 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)); @@ -749,6 +870,7 @@ int __init early_dbgp_init(char *s) return -1; } + dbgp_ehci_status("early_init_complete"); return 0; } @@ -758,9 +880,27 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n) int chunk, ret; char buf[DBGP_MAX_PACKET]; int use_cr = 0; + u32 cmd, ctrl; + int reset_run = 0; - if (!ehci_debug) + if (!ehci_debug || dbgp_not_safe) return; + + cmd = readl(&ehci_regs->command); + if (unlikely(!(cmd & CMD_RUN))) { + /* If the ehci controller is not in the run state do extended + * checks to see if the acpi or some other initialization also + * reset the ehci debug port */ + ctrl = readl(&ehci_debug->control); + if (!(ctrl & DBGP_ENABLED)) { + dbgp_not_safe = 1; + dbgp_external_startup(); + } else { + cmd |= CMD_RUN; + writel(cmd, &ehci_regs->command); + reset_run = 1; + } + } while (n > 0) { for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0; str++, chunk++, n--) { @@ -775,8 +915,15 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n) use_cr = 0; buf[chunk] = *str; } - ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, - dbgp_endpoint_out, buf, chunk); + if (chunk > 0) { + ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, + dbgp_endpoint_out, buf, chunk); + } + } + if (unlikely(reset_run)) { + cmd = readl(&ehci_regs->command); + cmd &= ~CMD_RUN; + writel(cmd, &ehci_regs->command); } } @@ -786,4 +933,3 @@ struct console early_dbgp_console = { .flags = CON_PRINTBUFFER, .index = -1, }; - diff --git a/include/linux/usb/ehci_def.h b/include/linux/usb/ehci_def.h index 1deac2a7b12e..07851e05d763 100644 --- a/include/linux/usb/ehci_def.h +++ b/include/linux/usb/ehci_def.h @@ -176,4 +176,9 @@ extern int __init early_dbgp_init(char *s); extern struct console early_dbgp_console; #endif /* CONFIG_EARLY_PRINTK_DBGP */ +#ifdef CONFIG_EARLY_PRINTK_DBGP +/* Call backs from ehci host driver to ehci debug driver */ +extern int dbgp_external_startup(void); +#endif + #endif /* __LINUX_USB_EHCI_DEF_H */