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path: root/drivers/usb/early/ehci-dbgp.c
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Diffstat (limited to 'drivers/usb/early/ehci-dbgp.c')
-rw-r--r--drivers/usb/early/ehci-dbgp.c159
1 files changed, 136 insertions, 23 deletions
diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 6e98a369784..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;
@@ -91,6 +96,16 @@ 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)
*/
@@ -182,11 +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 = DBGP_LOOPS;
retry:
writel(ctrl | DBGP_GO, &ehci_debug->control);
@@ -276,13 +290,13 @@ static int dbgp_bulk_write(unsigned devnum, unsigned endpoint,
dbgp_set_data(bytes, size);
writel(addr, &ehci_debug->address);
writel(pids, &ehci_debug->pids);
- ret = dbgp_wait_until_done(ctrl);
+ 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;
@@ -302,7 +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;
@@ -321,7 +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 */
@@ -343,12 +357,12 @@ 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 */
@@ -437,7 +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))
@@ -478,7 +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;
@@ -554,11 +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) {
@@ -590,7 +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;
@@ -599,7 +610,6 @@ err:
goto try_again;
return -ENODEV;
}
-EXPORT_SYMBOL_GPL(dbgp_external_startup);
static int ehci_reset_port(int port)
{
@@ -637,7 +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;
@@ -790,7 +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;
@@ -881,7 +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;
@@ -920,7 +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);
@@ -960,16 +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
@@ -982,3 +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 */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-05 21:45:27 +0000