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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.c442
1 files changed, 294 insertions, 148 deletions
diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index 6198ebded3a..06e05ea1787 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" <ebiederm@xmission.com> and
+ * Yinghai Lu <yhlu.kernel@gmail.com>
+ *
+ * Changes for early/late printk and HW errata:
+ * Jason Wessel <jason.wessel@windriver.com>
+ * Copyright (C) 2009 Wind River Systems, Inc.
+ *
+ */
+
#include <linux/console.h>
#include <linux/errno.h>
+#include <linux/module.h>
#include <linux/pci_regs.h>
#include <linux/pci_ids.h>
#include <linux/usb/ch9.h>
@@ -9,15 +23,37 @@
#include <asm/pci-direct.h>
#include <asm/fixmap.h>
-#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;
- }
- 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;
+ /* 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 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;
- }
- 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;
+ /* 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_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,
};
-
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-27 18:14:27 +0000