--- /dev/null
+/*
+ * 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>
+#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>
+
+/* 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;
+static unsigned int dbgp_endpoint_in;
+
+struct ehci_dev {
+ u32 bus;
+ u32 slot;
+ u32 func;
+};
+
+static struct ehci_dev ehci_dev;
+
+#define USB_DEBUG_DEVNUM 127
+
+#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_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)
+ */
+
+/* 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
+#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)
+{
+ u32 ctrl;
+ 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 -DBGP_TIMEOUT;
+
+ /*
+ * 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 inline 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, int loop)
+{
+ u32 pids, lpid;
+ int ret;
+
+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) {
+ /* 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;
+ if (ret == -DBGP_ERR_BAD && --loop > 0)
+ goto retry;
+ 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 inline 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 inline 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)
+{
+ 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_write_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, DBGP_LOOPS);
+
+ return ret;
+}
+
+static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data,
+ int size, int loops)
+{
+ 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_read_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, loops);
+ 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 = cpu_to_le16(value);
+ req.wIndex = cpu_to_le16(index);
+ req.wLength = cpu_to_le16(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, DBGP_LOOPS);
+ if (ret < 0)
+ return ret;
+
+ /* Read the result */
+ 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)
+{
+ 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 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 = 1000;
+ 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
+ */
+static int _dbgp_external_startup(void)
+{
+ int devnum;
+ struct usb_debug_descriptor dbgp_desc;
+ int ret;
+ u32 ctrl, portsc, cmd;
+ int dbg_port = dbgp_phys_port;
+ int tries = 3;
+ int reset_port_tries = 1;
+ int try_hard_once = 1;
+
+try_port_reset_again:
+ 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]);
+ if (!(portsc & PORT_CONNECT) && try_hard_once) {
+ /* Last ditch effort to try to force enable
+ * the debug device by using the packet test
+ * ehci command to try and wake it up. */
+ try_hard_once = 0;
+ cmd = readl(&ehci_regs->command);
+ cmd &= ~CMD_RUN;
+ writel(cmd, &ehci_regs->command);
+ portsc = readl(&ehci_regs->port_status[dbg_port - 1]);
+ portsc |= PORT_TEST_PKT;
+ writel(portsc, &ehci_regs->port_status[dbg_port - 1]);
+ dbgp_ehci_status("Trying to force debug port online");
+ mdelay(50);
+ dbgp_ehci_controller_reset();
+ goto try_port_reset_again;
+ } else if (reset_port_tries--) {
+ goto try_port_reset_again;
+ }
+ 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;
+ }
+ 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) {
+ 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 done\n");
+ dbgp_not_safe = 0;
+
+ return 0;
+err:
+ if (tries--)
+ goto try_again;
+ return -ENODEV;
+}
+
+static int ehci_reset_port(int port)
+{
+ u32 portsc;
+ u32 delay_time, delay;
+ int loop;
+
+ dbgp_ehci_status("reset port");
+ /* 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))
+ break;
+ }
+ if (portsc & PORT_RESET) {
+ /* force reset to complete */
+ loop = 100 * 1000;
+ writel(portsc & ~(PORT_RWC_BITS | PORT_RESET),
+ &ehci_regs->port_status[port - 1]);
+ do {
+ udelay(1);
+ 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 happened */
+ 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 < 300; reps++) {
+ status = readl(&ehci_regs->status);
+ if (status & STS_PCD)
+ break;
+ dbgp_mdelay(1);
+ }
+ ret = ehci_reset_port(port);
+ if (ret == 0)
+ return 0;
+ return -ENOTCONN;
+}
+
+typedef void (*set_debug_port_t)(int port);
+
+static void __init default_set_debug_port(int port)
+{
+}
+
+static set_debug_port_t __initdata set_debug_port = default_set_debug_port;
+
+static void __init 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;
+ }
+}
+
+/* The code in early_ehci_bios_handoff() is derived from the usb pci
+ * quirk initialization, but altered so as to use the early PCI
+ * routines. */
+#define EHCI_USBLEGSUP_BIOS (1 << 16) /* BIOS semaphore */
+#define EHCI_USBLEGCTLSTS 4 /* legacy control/status */
+static void __init early_ehci_bios_handoff(void)
+{
+ u32 hcc_params = readl(&ehci_caps->hcc_params);
+ int offset = (hcc_params >> 8) & 0xff;
+ u32 cap;
+ int msec;
+
+ if (!offset)
+ return;
+
+ cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+ ehci_dev.func, offset);
+ dbgp_printk("dbgp: ehci BIOS state %08x\n", cap);
+
+ if ((cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS)) {
+ dbgp_printk("dbgp: BIOS handoff\n");
+ write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+ ehci_dev.func, offset + 3, 1);
+ }
+
+ /* if boot firmware now owns EHCI, spin till it hands it over. */
+ msec = 1000;
+ while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
+ mdelay(10);
+ msec -= 10;
+ cap = read_pci_config(ehci_dev.bus, ehci_dev.slot,
+ ehci_dev.func, offset);
+ }
+
+ if (cap & EHCI_USBLEGSUP_BIOS) {
+ /* well, possibly buggy BIOS... try to shut it down,
+ * and hope nothing goes too wrong */
+ dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap);
+ write_pci_config_byte(ehci_dev.bus, ehci_dev.slot,
+ ehci_dev.func, offset + 2, 0);
+ }
+
+ /* just in case, always disable EHCI SMIs */
+ write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, ehci_dev.func,
+ offset + EHCI_USBLEGCTLSTS, 0);
+}
+
+static int __init ehci_setup(void)
+{
+ u32 ctrl, portsc, hcs_params;
+ u32 debug_port, new_debug_port = 0, n_ports;
+ int ret, i;
+ int port_map_tried;
+ int playtimes = 3;
+
+ early_ehci_bios_handoff();
+
+try_next_time:
+ port_map_tried = 0;
+
+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]);
+ 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;
+ }
+
+ /* 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");
+ }
+
+ ret = _dbgp_external_startup();
+ if (ret == -EIO)
+ goto next_debug_port;
+
+ if (ret < 0) {
+ /* 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;
+ }
+ return 0;
+
+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;
+}
+
+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 + EARLY_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 = NULL;
+
+ return -1;
+ }
+ dbgp_ehci_status("early_init_complete");
+
+ return 0;
+}
+
+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 || 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--) {
+ if (!use_cr && *str == '\n') {
+ use_cr = 1;
+ buf[chunk] = '\r';
+ str--;
+ n++;
+ continue;
+ }
+ if (use_cr)
+ use_cr = 0;
+ buf[chunk] = *str;
+ }
+ 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);
+ }
+}
+
+struct console early_dbgp_console = {
+ .name = "earlydbg",
+ .write = early_dbgp_write,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+
+#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)) ||
+ 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
+ * means it is time to shutdown the usb debug port. */
+ ctrl = readl(&ehci_debug->control);
+ if (ctrl & DBGP_ENABLED) {
+ ctrl &= ~(DBGP_CLAIM);
+ writel(ctrl, &ehci_debug->control);
+ }
+ 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 */
Code Review / kvmfornfv.git / blobdiff