diff options
Diffstat (limited to 'drivers/usb/early/ehci-dbgp.c')
| -rw-r--r-- | drivers/usb/early/ehci-dbgp.c | 223 |
1 files changed, 162 insertions, 61 deletions
diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c index 2958a1271b2..8cfc3191be5 100644 --- a/drivers/usb/early/ehci-dbgp.c +++ b/drivers/usb/early/ehci-dbgp.c @@ -19,6 +19,10 @@ #include <linux/usb/ch9.h> #include <linux/usb/ehci_def.h> #include <linux/delay.h> +#include <linux/serial_core.h> +#include <linux/kconfig.h> +#include <linux/kgdb.h> +#include <linux/kthread.h> #include <asm/io.h> #include <asm/pci-direct.h> #include <asm/fixmap.h> @@ -55,6 +59,7 @@ 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; +static unsigned int dbgp_endpoint_in; struct ehci_dev { u32 bus; @@ -66,8 +71,6 @@ static struct ehci_dev ehci_dev; #define USB_DEBUG_DEVNUM 127 -#define DBGP_DATA_TOGGLE 0x8800 - #ifdef DBGP_DEBUG #define dbgp_printk printk static void dbgp_ehci_status(char *str) @@ -88,16 +91,21 @@ 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); -} - static inline u32 dbgp_len_update(u32 x, u32 len) { return (x & ~0x0f) | (len & 0x0f); } +#ifdef CONFIG_KGDB +static struct kgdb_io kgdbdbgp_io_ops; +#define dbgp_kgdb_mode (dbg_io_ops == &kgdbdbgp_io_ops) +#else +#define dbgp_kgdb_mode (0) +#endif + +/* Local version of HC_LENGTH macro as ehci struct is not available here */ +#define EARLY_HC_LENGTH(p) (0x00ff & (p)) /* bits 7 : 0 */ + /* * USB Packet IDs (PIDs) */ @@ -136,6 +144,19 @@ static inline u32 dbgp_len_update(u32 x, u32 len) #define DBGP_MAX_PACKET 8 #define DBGP_TIMEOUT (250 * 1000) +#define DBGP_LOOPS 1000 + +static inline u32 dbgp_pid_write_update(u32 x, u32 tok) +{ + static int data0 = USB_PID_DATA1; + data0 ^= USB_PID_DATA_TOGGLE; + return (x & 0xffff0000) | (data0 << 8) | (tok & 0xff); +} + +static inline u32 dbgp_pid_read_update(u32 x, u32 tok) +{ + return (x & 0xffff0000) | (USB_PID_DATA0 << 8) | (tok & 0xff); +} static int dbgp_wait_until_complete(void) { @@ -176,11 +197,10 @@ static void dbgp_breath(void) /* Sleep to give the debug port a chance to breathe */ } -static int dbgp_wait_until_done(unsigned ctrl) +static int dbgp_wait_until_done(unsigned ctrl, int loop) { u32 pids, lpid; int ret; - int loop = 3; retry: writel(ctrl | DBGP_GO, &ehci_debug->control); @@ -197,6 +217,8 @@ retry: */ if (ret == -DBGP_TIMEOUT && !dbgp_not_safe) dbgp_not_safe = 1; + if (ret == -DBGP_ERR_BAD && --loop > 0) + goto retry; return ret; } @@ -245,12 +267,20 @@ static inline void dbgp_get_data(void *buf, int size) bytes[i] = (hi >> (8*(i - 4))) & 0xff; } -static int dbgp_out(u32 addr, const char *bytes, int size) +static int dbgp_bulk_write(unsigned devnum, unsigned endpoint, + const char *bytes, int size) { + int ret; + u32 addr; u32 pids, ctrl; + 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); + pids = dbgp_pid_write_update(pids, USB_PID_OUT); ctrl = readl(&ehci_debug->control); ctrl = dbgp_len_update(ctrl, size); @@ -260,40 +290,13 @@ static int dbgp_out(u32 addr, const char *bytes, int size) dbgp_set_data(bytes, size); writel(addr, &ehci_debug->address); writel(pids, &ehci_debug->pids); - return dbgp_wait_until_done(ctrl); -} - -static int dbgp_bulk_write(unsigned devnum, unsigned endpoint, - const char *bytes, int size) -{ - int ret; - int loops = 5; - u32 addr; - if (size > DBGP_MAX_PACKET) - return -1; - - addr = DBGP_EPADDR(devnum, endpoint); -try_again: - if (loops--) { - ret = dbgp_out(addr, bytes, size); - if (ret == -DBGP_ERR_BAD) { - int try_loops = 3; - do { - /* Emit a dummy packet to re-sync communication - * with the debug device */ - if (dbgp_out(addr, "12345678", 8) >= 0) { - udelay(2); - goto try_again; - } - } while (try_loops--); - } - } + ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS); return ret; } static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, - int size) + int size, int loops) { u32 pids, addr, ctrl; int ret; @@ -304,7 +307,7 @@ static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, addr = DBGP_EPADDR(devnum, endpoint); pids = readl(&ehci_debug->pids); - pids = dbgp_pid_update(pids, USB_PID_IN); + pids = dbgp_pid_read_update(pids, USB_PID_IN); ctrl = readl(&ehci_debug->control); ctrl = dbgp_len_update(ctrl, size); @@ -313,7 +316,7 @@ static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, writel(addr, &ehci_debug->address); writel(pids, &ehci_debug->pids); - ret = dbgp_wait_until_done(ctrl); + ret = dbgp_wait_until_done(ctrl, loops); if (ret < 0) return ret; @@ -332,7 +335,7 @@ static int dbgp_control_msg(unsigned devnum, int requesttype, int ret; read = (requesttype & USB_DIR_IN) != 0; - if (size > (read ? DBGP_MAX_PACKET:0)) + if (size > (read ? DBGP_MAX_PACKET : 0)) return -1; /* Compute the control message */ @@ -354,15 +357,14 @@ static int dbgp_control_msg(unsigned devnum, int requesttype, dbgp_set_data(&req, sizeof(req)); writel(addr, &ehci_debug->address); writel(pids, &ehci_debug->pids); - ret = dbgp_wait_until_done(ctrl); + ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS); if (ret < 0) return ret; /* Read the result */ - return dbgp_bulk_read(devnum, 0, data, size); + return dbgp_bulk_read(devnum, 0, data, size, DBGP_LOOPS); } - /* Find a PCI capability */ static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap) { @@ -449,7 +451,7 @@ static int dbgp_ehci_startup(void) writel(FLAG_CF, &ehci_regs->configured_flag); /* Wait until the controller is no longer halted */ - loop = 10; + loop = 1000; do { status = readl(&ehci_regs->status); if (!(status & STS_HALT)) @@ -490,7 +492,7 @@ static int ehci_wait_for_port(int port); * Return -ENODEV for any general failure * Return -EIO if wait for port fails */ -int dbgp_external_startup(void) +static int _dbgp_external_startup(void) { int devnum; struct usb_debug_descriptor dbgp_desc; @@ -566,11 +568,8 @@ try_again: 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; + dbgp_endpoint_in = dbgp_desc.bDebugInEndpoint; /* Move the device to 127 if it isn't already there */ if (devnum != USB_DEBUG_DEVNUM) { @@ -602,7 +601,7 @@ try_again: dbgp_printk("dbgp_bulk_write failed: %d\n", ret); goto err; } - dbgp_printk("small write doned\n"); + dbgp_printk("small write done\n"); dbgp_not_safe = 0; return 0; @@ -611,7 +610,6 @@ err: goto try_again; return -ENODEV; } -EXPORT_SYMBOL_GPL(dbgp_external_startup); static int ehci_reset_port(int port) { @@ -649,7 +647,7 @@ static int ehci_reset_port(int port) if (!(portsc & PORT_CONNECT)) return -ENOTCONN; - /* bomb out completely if something weird happend */ + /* bomb out completely if something weird happened */ if ((portsc & PORT_CSC)) return -EINVAL; @@ -802,7 +800,7 @@ try_next_port: dbgp_ehci_status("ehci skip - already configured"); } - ret = dbgp_external_startup(); + ret = _dbgp_external_startup(); if (ret == -EIO) goto next_debug_port; @@ -893,7 +891,7 @@ int __init early_dbgp_init(char *s) dbgp_printk("ehci_bar: %p\n", ehci_bar); ehci_caps = ehci_bar; - ehci_regs = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase)); + ehci_regs = ehci_bar + EARLY_HC_LENGTH(readl(&ehci_caps->hc_capbase)); ehci_debug = ehci_bar + offset; ehci_dev.bus = bus; ehci_dev.slot = slot; @@ -932,7 +930,7 @@ static void early_dbgp_write(struct console *con, const char *str, u32 n) ctrl = readl(&ehci_debug->control); if (!(ctrl & DBGP_ENABLED)) { dbgp_not_safe = 1; - dbgp_external_startup(); + _dbgp_external_startup(); } else { cmd |= CMD_RUN; writel(cmd, &ehci_regs->command); @@ -972,16 +970,22 @@ struct console early_dbgp_console = { .index = -1, }; -int dbgp_reset_prep(void) +#if IS_ENABLED(CONFIG_USB) +int dbgp_reset_prep(struct usb_hcd *hcd) { + int ret = xen_dbgp_reset_prep(hcd); u32 ctrl; + if (ret) + return ret; + dbgp_not_safe = 1; if (!ehci_debug) return 0; - if (early_dbgp_console.index != -1 && - !(early_dbgp_console.flags & CON_BOOT)) + if ((early_dbgp_console.index != -1 && + !(early_dbgp_console.flags & CON_BOOT)) || + dbgp_kgdb_mode) return 1; /* This means the console is not initialized, or should get * shutdown so as to allow for reuse of the usb device, which @@ -994,3 +998,100 @@ int dbgp_reset_prep(void) return 0; } EXPORT_SYMBOL_GPL(dbgp_reset_prep); + +int dbgp_external_startup(struct usb_hcd *hcd) +{ + return xen_dbgp_external_startup(hcd) ?: _dbgp_external_startup(); +} +EXPORT_SYMBOL_GPL(dbgp_external_startup); +#endif /* USB */ + +#ifdef CONFIG_KGDB + +static char kgdbdbgp_buf[DBGP_MAX_PACKET]; +static int kgdbdbgp_buf_sz; +static int kgdbdbgp_buf_idx; +static int kgdbdbgp_loop_cnt = DBGP_LOOPS; + +static int kgdbdbgp_read_char(void) +{ + int ret; + + if (kgdbdbgp_buf_idx < kgdbdbgp_buf_sz) { + char ch = kgdbdbgp_buf[kgdbdbgp_buf_idx++]; + return ch; + } + + ret = dbgp_bulk_read(USB_DEBUG_DEVNUM, dbgp_endpoint_in, + &kgdbdbgp_buf, DBGP_MAX_PACKET, + kgdbdbgp_loop_cnt); + if (ret <= 0) + return NO_POLL_CHAR; + kgdbdbgp_buf_sz = ret; + kgdbdbgp_buf_idx = 1; + return kgdbdbgp_buf[0]; +} + +static void kgdbdbgp_write_char(u8 chr) +{ + early_dbgp_write(NULL, &chr, 1); +} + +static struct kgdb_io kgdbdbgp_io_ops = { + .name = "kgdbdbgp", + .read_char = kgdbdbgp_read_char, + .write_char = kgdbdbgp_write_char, +}; + +static int kgdbdbgp_wait_time; + +static int __init kgdbdbgp_parse_config(char *str) +{ + char *ptr; + + if (!ehci_debug) { + if (early_dbgp_init(str)) + return -1; + } + ptr = strchr(str, ','); + if (ptr) { + ptr++; + kgdbdbgp_wait_time = simple_strtoul(ptr, &ptr, 10); + } + kgdb_register_io_module(&kgdbdbgp_io_ops); + kgdbdbgp_io_ops.is_console = early_dbgp_console.index != -1; + + return 0; +} +early_param("kgdbdbgp", kgdbdbgp_parse_config); + +static int kgdbdbgp_reader_thread(void *ptr) +{ + int ret; + + while (readl(&ehci_debug->control) & DBGP_ENABLED) { + kgdbdbgp_loop_cnt = 1; + ret = kgdbdbgp_read_char(); + kgdbdbgp_loop_cnt = DBGP_LOOPS; + if (ret != NO_POLL_CHAR) { + if (ret == 0x3 || ret == '$') { + if (ret == '$') + kgdbdbgp_buf_idx--; + kgdb_breakpoint(); + } + continue; + } + schedule_timeout_interruptible(kgdbdbgp_wait_time * HZ); + } + return 0; +} + +static int __init kgdbdbgp_start_thread(void) +{ + if (dbgp_kgdb_mode && kgdbdbgp_wait_time) + kthread_run(kgdbdbgp_reader_thread, NULL, "%s", "dbgp"); + + return 0; +} +module_init(kgdbdbgp_start_thread); +#endif /* CONFIG_KGDB */ |