3 files changed, 826 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci-dbg.c b/drivers/usb/host/xhci-dbg.c
new file mode 100644
index 00000000000..a7798b46049
--- /dev/null
+++ b/drivers/usb/host/xhci-dbg.c
@@ -0,0 +1,229 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "xhci.h"
+
+#define XHCI_INIT_VALUE 0x0
+
+/* Add verbose debugging later, just print everything for now */
+
+void xhci_dbg_regs(struct xhci_hcd *xhci)
+{
+        u32 temp;
+
+        xhci_dbg(xhci, "// xHCI capability registers at 0x%x:\n",
+                        (unsigned int) xhci->cap_regs);
+        temp = xhci_readl(xhci, &xhci->cap_regs->hc_capbase);
+        xhci_dbg(xhci, "// @%x = 0x%x (CAPLENGTH AND HCIVERSION)\n",
+                        (unsigned int) &xhci->cap_regs->hc_capbase,
+                        (unsigned int) temp);
+        xhci_dbg(xhci, "//   CAPLENGTH: 0x%x\n",
+                        (unsigned int) HC_LENGTH(temp));
+#if 0
+        xhci_dbg(xhci, "//   HCIVERSION: 0x%x\n",
+                        (unsigned int) HC_VERSION(temp));
+#endif
+
+        xhci_dbg(xhci, "// xHCI operational registers at 0x%x:\n",
+                        (unsigned int) xhci->op_regs);
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->run_regs_off);
+        xhci_dbg(xhci, "// @%x = 0x%x RTSOFF\n",
+                        (unsigned int) &xhci->cap_regs->run_regs_off,
+                        (unsigned int) temp & RTSOFF_MASK);
+        xhci_dbg(xhci, "// xHCI runtime registers at 0x%x:\n",
+                        (unsigned int) xhci->run_regs);
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->db_off);
+        xhci_dbg(xhci, "// @%x = 0x%x DBOFF\n",
+                        (unsigned int) &xhci->cap_regs->db_off, temp);
+}
+
+void xhci_print_cap_regs(struct xhci_hcd *xhci)
+{
+        u32 temp;
+
+        xhci_dbg(xhci, "xHCI capability registers at 0x%x:\n",
+                        (unsigned int) xhci->cap_regs);
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->hc_capbase);
+        xhci_dbg(xhci, "CAPLENGTH AND HCIVERSION 0x%x:\n",
+                        (unsigned int) temp);
+        xhci_dbg(xhci, "CAPLENGTH: 0x%x\n",
+                        (unsigned int) HC_LENGTH(temp));
+        xhci_dbg(xhci, "HCIVERSION: 0x%x\n",
+                        (unsigned int) HC_VERSION(temp));
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->hcs_params1);
+        xhci_dbg(xhci, "HCSPARAMS 1: 0x%x\n",
+                        (unsigned int) temp);
+        xhci_dbg(xhci, "  Max device slots: %u\n",
+                        (unsigned int) HCS_MAX_SLOTS(temp));
+        xhci_dbg(xhci, "  Max interrupters: %u\n",
+                        (unsigned int) HCS_MAX_INTRS(temp));
+        xhci_dbg(xhci, "  Max ports: %u\n",
+                        (unsigned int) HCS_MAX_PORTS(temp));
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->hcs_params2);
+        xhci_dbg(xhci, "HCSPARAMS 2: 0x%x\n",
+                        (unsigned int) temp);
+        xhci_dbg(xhci, "  Isoc scheduling threshold: %u\n",
+                        (unsigned int) HCS_IST(temp));
+        xhci_dbg(xhci, "  Maximum allowed segments in event ring: %u\n",
+                        (unsigned int) HCS_ERST_MAX(temp));
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->hcs_params3);
+        xhci_dbg(xhci, "HCSPARAMS 3 0x%x:\n",
+                        (unsigned int) temp);
+        xhci_dbg(xhci, "  Worst case U1 device exit latency: %u\n",
+                        (unsigned int) HCS_U1_LATENCY(temp));
+        xhci_dbg(xhci, "  Worst case U2 device exit latency: %u\n",
+                        (unsigned int) HCS_U2_LATENCY(temp));
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
+        xhci_dbg(xhci, "HCC PARAMS 0x%x:\n", (unsigned int) temp);
+        xhci_dbg(xhci, "  HC generates %s bit addresses\n",
+                        HCC_64BIT_ADDR(temp) ? "64" : "32");
+        /* FIXME */
+        xhci_dbg(xhci, "  FIXME: more HCCPARAMS debugging\n");
+
+        temp = xhci_readl(xhci, &xhci->cap_regs->run_regs_off);
+        xhci_dbg(xhci, "RTSOFF 0x%x:\n", temp & RTSOFF_MASK);
+}
+
+void xhci_print_command_reg(struct xhci_hcd *xhci)
+{
+        u32 temp;
+
+        temp = xhci_readl(xhci, &xhci->op_regs->command);
+        xhci_dbg(xhci, "USBCMD 0x%x:\n", temp);
+        xhci_dbg(xhci, "  HC is %s\n",
+                        (temp & CMD_RUN) ? "running" : "being stopped");
+        xhci_dbg(xhci, "  HC has %sfinished hard reset\n",
+                        (temp & CMD_RESET) ? "not " : "");
+        xhci_dbg(xhci, "  Event Interrupts %s\n",
+                        (temp & CMD_EIE) ? "enabled " : "disabled");
+        xhci_dbg(xhci, "  Host System Error Interrupts %s\n",
+                        (temp & CMD_EIE) ? "enabled " : "disabled");
+        xhci_dbg(xhci, "  HC has %sfinished light reset\n",
+                        (temp & CMD_LRESET) ? "not " : "");
+}
+
+void xhci_print_status(struct xhci_hcd *xhci)
+{
+        u32 temp;
+
+        temp = xhci_readl(xhci, &xhci->op_regs->status);
+        xhci_dbg(xhci, "USBSTS 0x%x:\n", temp);
+        xhci_dbg(xhci, "  Event ring is %sempty\n",
+                        (temp & STS_EINT) ? "not " : "");
+        xhci_dbg(xhci, "  %sHost System Error\n",
+                        (temp & STS_FATAL) ? "WARNING: " : "No ");
+        xhci_dbg(xhci, "  HC is %s\n",
+                        (temp & STS_HALT) ? "halted" : "running");
+}
+
+void xhci_print_op_regs(struct xhci_hcd *xhci)
+{
+        xhci_dbg(xhci, "xHCI operational registers at 0x%x:\n",
+                        (unsigned int) xhci->op_regs);
+        xhci_print_command_reg(xhci);
+        xhci_print_status(xhci);
+}
+
+void xhci_print_ir_set(struct xhci_hcd *xhci, struct intr_reg *ir_set, int set_num)
+{
+        void *addr;
+        u32 temp;
+
+        addr = &ir_set->irq_pending;
+        temp = xhci_readl(xhci, addr);
+        if (temp == XHCI_INIT_VALUE)
+                return;
+
+        xhci_dbg(xhci, "  0x%x: ir_set[%i]\n", (unsigned int) ir_set, set_num);
+
+        xhci_dbg(xhci, "  0x%x: ir_set.pending = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->irq_control;
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.control = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->erst_size;
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.erst_size = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->rsvd;
+        temp = xhci_readl(xhci, addr);
+        if (temp != XHCI_INIT_VALUE)
+                xhci_dbg(xhci, "  WARN: 0x%x: ir_set.rsvd = 0x%x\n",
+                                (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->erst_base[0];
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.erst_base[0] = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->erst_base[1];
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.erst_base[1] = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->erst_dequeue[0];
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.erst_dequeue[0] = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+
+        addr = &ir_set->erst_dequeue[1];
+        temp = xhci_readl(xhci, addr);
+        xhci_dbg(xhci, "  0x%x: ir_set.erst_dequeue[1] = 0x%x\n",
+                        (unsigned int) addr, (unsigned int) temp);
+}
+
+void xhci_print_run_regs(struct xhci_hcd *xhci)
+{
+        u32 temp;
+        int i;
+
+        xhci_dbg(xhci, "xHCI runtime registers at 0x%x:\n",
+                        (unsigned int) xhci->run_regs);
+        temp = xhci_readl(xhci, &xhci->run_regs->microframe_index);
+        xhci_dbg(xhci, "  0x%x: Microframe index = 0x%x\n",
+                        (unsigned int) &xhci->run_regs->microframe_index,
+                        (unsigned int) temp);
+        for (i = 0; i < 7; ++i) {
+                temp = xhci_readl(xhci, &xhci->run_regs->rsvd[i]);
+                if (temp != XHCI_INIT_VALUE)
+                        xhci_dbg(xhci, "  WARN: 0x%x: Rsvd[%i] = 0x%x\n",
+                                        (unsigned int) &xhci->run_regs->rsvd[i],
+                                        i, (unsigned int) temp);
+        }
+}
+
+void xhci_print_registers(struct xhci_hcd *xhci)
+{
+        xhci_print_cap_regs(xhci);
+        xhci_print_op_regs(xhci);
+}
diff --git a/drivers/usb/host/xhci-ext-caps.h b/drivers/usb/host/xhci-ext-caps.h
new file mode 100644
index 00000000000..ecc131c3fe3
--- /dev/null
+++ b/drivers/usb/host/xhci-ext-caps.h
@@ -0,0 +1,145 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+/* Up to 16 microframes to halt an HC - one microframe is 125 microsectonds */
+#define XHCI_MAX_HALT_USEC      (16*125)
+/* HC not running - set to 1 when run/stop bit is cleared. */
+#define XHCI_STS_HALT           (1<<0)
+
+/* HCCPARAMS offset from PCI base address */
+#define XHCI_HCC_PARAMS_OFFSET  0x10
+/* HCCPARAMS contains the first extended capability pointer */
+#define XHCI_HCC_EXT_CAPS(p)    (((p)>>16)&0xffff)
+
+/* Command and Status registers offset from the Operational Registers address */
+#define XHCI_CMD_OFFSET         0x00
+#define XHCI_STS_OFFSET         0x04
+
+#define XHCI_MAX_EXT_CAPS               50
+
+/* Capability Register */
+/* bits 7:0 - how long is the Capabilities register */
+#define XHCI_HC_LENGTH(p)       (((p)>>00)&0x00ff)
+
+/* Extended capability register fields */
+#define XHCI_EXT_CAPS_ID(p)     (((p)>>0)&0xff)
+#define XHCI_EXT_CAPS_NEXT(p)   (((p)>>8)&0xff)
+#define XHCI_EXT_CAPS_VAL(p)    ((p)>>16)
+/* Extended capability IDs - ID 0 reserved */
+#define XHCI_EXT_CAPS_LEGACY    1
+#define XHCI_EXT_CAPS_PROTOCOL  2
+#define XHCI_EXT_CAPS_PM        3
+#define XHCI_EXT_CAPS_VIRT      4
+#define XHCI_EXT_CAPS_ROUTE     5
+/* IDs 6-9 reserved */
+#define XHCI_EXT_CAPS_DEBUG     10
+/* USB Legacy Support Capability - section 7.1.1 */
+#define XHCI_HC_BIOS_OWNED      (1 << 16)
+#define XHCI_HC_OS_OWNED        (1 << 24)
+
+/* USB Legacy Support Capability - section 7.1.1 */
+/* Add this offset, plus the value of xECP in HCCPARAMS to the base address */
+#define XHCI_LEGACY_SUPPORT_OFFSET      (0x00)
+
+/* USB Legacy Support Control and Status Register  - section 7.1.2 */
+/* Add this offset, plus the value of xECP in HCCPARAMS to the base address */
+#define XHCI_LEGACY_CONTROL_OFFSET      (0x04)
+/* bits 1:2, 5:12, and 17:19 need to be preserved; bits 21:28 should be zero */
+#define XHCI_LEGACY_DISABLE_SMI         ((0x3 << 1) + (0xff << 5) + (0x7 << 17))
+
+/* command register values to disable interrupts and halt the HC */
+/* start/stop HC execution - do not write unless HC is halted*/
+#define XHCI_CMD_RUN            (1 << 0)
+/* Event Interrupt Enable - get irq when EINT bit is set in USBSTS register */
+#define XHCI_CMD_EIE            (1 << 2)
+/* Host System Error Interrupt Enable - get irq when HSEIE bit set in USBSTS */
+#define XHCI_CMD_HSEIE          (1 << 3)
+/* Enable Wrap Event - '1' means xHC generates an event when MFINDEX wraps. */
+#define XHCI_CMD_EWE            (1 << 10)
+
+#define XHCI_IRQS               (XHCI_CMD_EIE | XHCI_CMD_HSEIE | XHCI_CMD_EWE)
+
+/* true: Controller Not Ready to accept doorbell or op reg writes after reset */
+#define XHCI_STS_CNR            (1 << 11)
+
+#include <linux/io.h>
+
+/**
+ * Return the next extended capability pointer register.
+ *
+ * @base        PCI register base address.
+ *
+ * @ext_offset  Offset of the 32-bit register that contains the extended
+ * capabilites pointer.  If searching for the first extended capability, pass
+ * in XHCI_HCC_PARAMS_OFFSET.  If searching for the next extended capability,
+ * pass in the offset of the current extended capability register.
+ *
+ * Returns 0 if there is no next extended capability register or returns the register offset
+ * from the PCI registers base address.
+ */
+static inline int xhci_find_next_cap_offset(void __iomem *base, int ext_offset)
+{
+        u32 next;
+
+        next = readl(base + ext_offset);
+
+        if (ext_offset == XHCI_HCC_PARAMS_OFFSET)
+                /* Find the first extended capability */
+                next = XHCI_HCC_EXT_CAPS(next);
+        else
+                /* Find the next extended capability */
+                next = XHCI_EXT_CAPS_NEXT(next);
+        if (!next)
+                return 0;
+        /*
+         * Address calculation from offset of extended capabilities
+         * (or HCCPARAMS) register - see section 5.3.6 and section 7.
+         */
+        return ext_offset + (next << 2);
+}
+
+/**
+ * Find the offset of the extended capabilities with capability ID id.
+ *
+ * @base PCI MMIO registers base address.
+ * @ext_offset Offset from base of the first extended capability to look at,
+ *              or the address of HCCPARAMS.
+ * @id Extended capability ID to search for.
+ *
+ * This uses an arbitrary limit of XHCI_MAX_EXT_CAPS extended capabilities
+ * to make sure that the list doesn't contain a loop.
+ */
+static inline int xhci_find_ext_cap_by_id(void __iomem *base, int ext_offset, int id)
+{
+        u32 val;
+        int limit = XHCI_MAX_EXT_CAPS;
+
+        while (ext_offset && limit > 0) {
+                val = readl(base + ext_offset);
+                if (XHCI_EXT_CAPS_ID(val) == id)
+                        break;
+                ext_offset = xhci_find_next_cap_offset(base, ext_offset);
+                limit--;
+        }
+        if (limit > 0)
+                return ext_offset;
+        return 0;
+}
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
new file mode 100644
index 00000000000..a4d44aad069
--- /dev/null
+++ b/drivers/usb/host/xhci.h
@@ -0,0 +1,452 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __LINUX_XHCI_HCD_H
+#define __LINUX_XHCI_HCD_H
+
+#include <linux/usb.h>
+
+#include "../core/hcd.h"
+/* Code sharing between pci-quirks and xhci hcd */
+#include        "xhci-ext-caps.h"
+
+/* xHCI PCI Configuration Registers */
+#define XHCI_SBRN_OFFSET        (0x60)
+
+/*
+ * xHCI register interface.
+ * This corresponds to the eXtensible Host Controller Interface (xHCI)
+ * Revision 0.95 specification
+ *
+ * Registers should always be accessed with double word or quad word accesses.
+ *
+ * Some xHCI implementations may support 64-bit address pointers.  Registers
+ * with 64-bit address pointers should be written to with dword accesses by
+ * writing the low dword first (ptr[0]), then the high dword (ptr[1]) second.
+ * xHCI implementations that do not support 64-bit address pointers will ignore
+ * the high dword, and write order is irrelevant.
+ */
+
+/**
+ * struct xhci_cap_regs - xHCI Host Controller Capability Registers.
+ * @hc_capbase:         length of the capabilities register and HC version number
+ * @hcs_params1:        HCSPARAMS1 - Structural Parameters 1
+ * @hcs_params2:        HCSPARAMS2 - Structural Parameters 2
+ * @hcs_params3:        HCSPARAMS3 - Structural Parameters 3
+ * @hcc_params:         HCCPARAMS - Capability Parameters
+ * @db_off:             DBOFF - Doorbell array offset
+ * @run_regs_off:       RTSOFF - Runtime register space offset
+ */
+struct xhci_cap_regs {
+        u32     hc_capbase;
+        u32     hcs_params1;
+        u32     hcs_params2;
+        u32     hcs_params3;
+        u32     hcc_params;
+        u32     db_off;
+        u32     run_regs_off;
+        /* Reserved up to (CAPLENGTH - 0x1C) */
+} __attribute__ ((packed));
+
+/* hc_capbase bitmasks */
+/* bits 7:0 - how long is the Capabilities register */
+#define HC_LENGTH(p)            XHCI_HC_LENGTH(p)
+/* bits 31:16   */
+#define HC_VERSION(p)           (((p) >> 16) & 0xffff)
+
+/* HCSPARAMS1 - hcs_params1 - bitmasks */
+/* bits 0:7, Max Device Slots */
+#define HCS_MAX_SLOTS(p)        (((p) >> 0) & 0xff)
+#define HCS_SLOTS_MASK          0xff
+/* bits 8:18, Max Interrupters */
+#define HCS_MAX_INTRS(p)        (((p) >> 8) & 0x7ff)
+/* bits 24:31, Max Ports - max value is 0x7F = 127 ports */
+#define HCS_MAX_PORTS(p)        (((p) >> 24) & 0x7f)
+
+/* HCSPARAMS2 - hcs_params2 - bitmasks */
+/* bits 0:3, frames or uframes that SW needs to queue transactions
+ * ahead of the HW to meet periodic deadlines */
+#define HCS_IST(p)              (((p) >> 0) & 0xf)
+/* bits 4:7, max number of Event Ring segments */
+#define HCS_ERST_MAX(p)         (((p) >> 4) & 0xf)
+/* bit 26 Scratchpad restore - for save/restore HW state - not used yet */
+/* bits 27:31 number of Scratchpad buffers SW must allocate for the HW */
+
+/* HCSPARAMS3 - hcs_params3 - bitmasks */
+/* bits 0:7, Max U1 to U0 latency for the roothub ports */
+#define HCS_U1_LATENCY(p)       (((p) >> 0) & 0xff)
+/* bits 16:31, Max U2 to U0 latency for the roothub ports */
+#define HCS_U2_LATENCY(p)       (((p) >> 16) & 0xffff)
+
+/* HCCPARAMS - hcc_params - bitmasks */
+/* true: HC can use 64-bit address pointers */
+#define HCC_64BIT_ADDR(p)       ((p) & (1 << 0))
+/* true: HC can do bandwidth negotiation */
+#define HCC_BANDWIDTH_NEG(p)    ((p) & (1 << 1))
+/* true: HC uses 64-byte Device Context structures
+ * FIXME 64-byte context structures aren't supported yet.
+ */
+#define HCC_64BYTE_CONTEXT(p)   ((p) & (1 << 2))
+/* true: HC has port power switches */
+#define HCC_PPC(p)              ((p) & (1 << 3))
+/* true: HC has port indicators */
+#define HCS_INDICATOR(p)        ((p) & (1 << 4))
+/* true: HC has Light HC Reset Capability */
+#define HCC_LIGHT_RESET(p)      ((p) & (1 << 5))
+/* true: HC supports latency tolerance messaging */
+#define HCC_LTC(p)              ((p) & (1 << 6))
+/* true: no secondary Stream ID Support */
+#define HCC_NSS(p)              ((p) & (1 << 7))
+/* Max size for Primary Stream Arrays - 2^(n+1), where n is bits 12:15 */
+#define HCC_MAX_PSA             (1 << ((((p) >> 12) & 0xf) + 1))
+/* Extended Capabilities pointer from PCI base - section 5.3.6 */
+#define HCC_EXT_CAPS(p)         XHCI_HCC_EXT_CAPS(p)
+
+/* db_off bitmask - bits 0:1 reserved */
+#define DBOFF_MASK      (~0x3)
+
+/* run_regs_off bitmask - bits 0:4 reserved */
+#define RTSOFF_MASK     (~0x1f)
+
+
+/* Number of registers per port */
+#define NUM_PORT_REGS   4
+
+/**
+ * struct xhci_op_regs - xHCI Host Controller Operational Registers.
+ * @command:            USBCMD - xHC command register
+ * @status:             USBSTS - xHC status register
+ * @page_size:          This indicates the page size that the host controller
+ *                      supports.  If bit n is set, the HC supports a page size
+ *                      of 2^(n+12), up to a 128MB page size.
+ *                      4K is the minimum page size.
+ * @cmd_ring:           CRP - 64-bit Command Ring Pointer
+ * @dcbaa_ptr:          DCBAAP - 64-bit Device Context Base Address Array Pointer
+ * @config_reg:         CONFIG - Configure Register
+ * @port_status_base:   PORTSCn - base address for Port Status and Control
+ *                      Each port has a Port Status and Control register,
+ *                      followed by a Port Power Management Status and Control
+ *                      register, a Port Link Info register, and a reserved
+ *                      register.
+ * @port_power_base:    PORTPMSCn - base address for
+ *                      Port Power Management Status and Control
+ * @port_link_base:     PORTLIn - base address for Port Link Info (current
+ *                      Link PM state and control) for USB 2.1 and USB 3.0
+ *                      devices.
+ */
+struct xhci_op_regs {
+        u32     command;
+        u32     status;
+        u32     page_size;
+        u32     reserved1;
+        u32     reserved2;
+        u32     dev_notification;
+        u32     cmd_ring[2];
+        /* rsvd: offset 0x20-2F */
+        u32     reserved3[4];
+        u32     dcbaa_ptr[2];
+        u32     config_reg;
+        /* rsvd: offset 0x3C-3FF */
+        u32     reserved4[241];
+        /* port 1 registers, which serve as a base address for other ports */
+        u32     port_status_base;
+        u32     port_power_base;
+        u32     port_link_base;
+        u32     reserved5;
+        /* registers for ports 2-255 */
+        u32     reserved6[NUM_PORT_REGS*254];
+} __attribute__ ((packed));
+
+/* USBCMD - USB command - command bitmasks */
+/* start/stop HC execution - do not write unless HC is halted*/
+#define CMD_RUN         XHCI_CMD_RUN
+/* Reset HC - resets internal HC state machine and all registers (except
+ * PCI config regs).  HC does NOT drive a USB reset on the downstream ports.
+ * The xHCI driver must reinitialize the xHC after setting this bit.
+ */
+#define CMD_RESET       (1 << 1)
+/* Event Interrupt Enable - a '1' allows interrupts from the host controller */
+#define CMD_EIE         XHCI_CMD_EIE
+/* Host System Error Interrupt Enable - get out-of-band signal for HC errors */
+#define CMD_HSEIE       XHCI_CMD_HSEIE
+/* bits 4:6 are reserved (and should be preserved on writes). */
+/* light reset (port status stays unchanged) - reset completed when this is 0 */
+#define CMD_LRESET      (1 << 7)
+/* FIXME: ignoring host controller save/restore state for now. */
+#define CMD_CSS         (1 << 8)
+#define CMD_CRS         (1 << 9)
+/* Enable Wrap Event - '1' means xHC generates an event when MFINDEX wraps. */
+#define CMD_EWE         XHCI_CMD_EWE
+/* MFINDEX power management - '1' means xHC can stop MFINDEX counter if all root
+ * hubs are in U3 (selective suspend), disconnect, disabled, or powered-off.
+ * '0' means the xHC can power it off if all ports are in the disconnect,
+ * disabled, or powered-off state.
+ */
+#define CMD_PM_INDEX    (1 << 11)
+/* bits 12:31 are reserved (and should be preserved on writes). */
+
+/* USBSTS - USB status - status bitmasks */
+/* HC not running - set to 1 when run/stop bit is cleared. */
+#define STS_HALT        XHCI_STS_HALT
+/* serious error, e.g. PCI parity error.  The HC will clear the run/stop bit. */
+#define STS_FATAL       (1 << 2)
+/* event interrupt - clear this prior to clearing any IP flags in IR set*/
+#define STS_EINT        (1 << 3)
+/* port change detect */
+#define STS_PORT        (1 << 4)
+/* bits 5:7 reserved and zeroed */
+/* save state status - '1' means xHC is saving state */
+#define STS_SAVE        (1 << 8)
+/* restore state status - '1' means xHC is restoring state */
+#define STS_RESTORE     (1 << 9)
+/* true: save or restore error */
+#define STS_SRE         (1 << 10)
+/* true: Controller Not Ready to accept doorbell or op reg writes after reset */
+#define STS_CNR         XHCI_STS_CNR
+/* true: internal Host Controller Error - SW needs to reset and reinitialize */
+#define STS_HCE         (1 << 12)
+/* bits 13:31 reserved and should be preserved */
+
+/*
+ * DNCTRL - Device Notification Control Register - dev_notification bitmasks
+ * Generate a device notification event when the HC sees a transaction with a
+ * notification type that matches a bit set in this bit field.
+ */
+#define DEV_NOTE_MASK           (0xffff)
+#define ENABLE_DEV_NOTE(x)      (1 << x)
+/* Most of the device notification types should only be used for debug.
+ * SW does need to pay attention to function wake notifications.
+ */
+#define DEV_NOTE_FWAKE          ENABLE_DEV_NOTE(1)
+
+/* CONFIG - Configure Register - config_reg bitmasks */
+/* bits 0:7 - maximum number of device slots enabled (NumSlotsEn) */
+#define MAX_DEVS(p)     ((p) & 0xff)
+/* bits 8:31 - reserved and should be preserved */
+
+/* PORTSC - Port Status and Control Register - port_status_base bitmasks */
+/* true: device connected */
+#define PORT_CONNECT    (1 << 0)
+/* true: port enabled */
+#define PORT_PE         (1 << 1)
+/* bit 2 reserved and zeroed */
+/* true: port has an over-current condition */
+#define PORT_OC         (1 << 3)
+/* true: port reset signaling asserted */
+#define PORT_RESET      (1 << 4)
+/* Port Link State - bits 5:8
+ * A read gives the current link PM state of the port,
+ * a write with Link State Write Strobe set sets the link state.
+ */
+/* true: port has power (see HCC_PPC) */
+#define PORT_POWER      (1 << 9)
+/* bits 10:13 indicate device speed:
+ * 0 - undefined speed - port hasn't be initialized by a reset yet
+ * 1 - full speed
+ * 2 - low speed
+ * 3 - high speed
+ * 4 - super speed
+ * 5-15 reserved
+ */
+#define DEV_SPEED_MASK          (0xf<<10)
+#define DEV_UNDEFSPEED(p)       (((p) & DEV_SPEED_MASK) == (0x0<<10))
+#define DEV_FULLSPEED(p)        (((p) & DEV_SPEED_MASK) == (0x1<<10))
+#define DEV_LOWSPEED(p)         (((p) & DEV_SPEED_MASK) == (0x2<<10))
+#define DEV_HIGHSPEED(p)        (((p) & DEV_SPEED_MASK) == (0x3<<10))
+#define DEV_SUPERSPEED(p)       (((p) & DEV_SPEED_MASK) == (0x4<<10))
+/* Port Indicator Control */
+#define PORT_LED_OFF    (0 << 14)
+#define PORT_LED_AMBER  (1 << 14)
+#define PORT_LED_GREEN  (2 << 14)
+#define PORT_LED_MASK   (3 << 14)
+/* Port Link State Write Strobe - set this when changing link state */
+#define PORT_LINK_STROBE        (1 << 16)
+/* true: connect status change */
+#define PORT_CSC        (1 << 17)
+/* true: port enable change */
+#define PORT_PEC        (1 << 18)
+/* true: warm reset for a USB 3.0 device is done.  A "hot" reset puts the port
+ * into an enabled state, and the device into the default state.  A "warm" reset
+ * also resets the link, forcing the device through the link training sequence.
+ * SW can also look at the Port Reset register to see when warm reset is done.
+ */
+#define PORT_WRC        (1 << 19)
+/* true: over-current change */
+#define PORT_OCC        (1 << 20)
+/* true: reset change - 1 to 0 transition of PORT_RESET */
+#define PORT_RC         (1 << 21)
+/* port link status change - set on some port link state transitions:
+ *  Transition                          Reason
+ *  ------------------------------------------------------------------------------
+ *  - U3 to Resume                      Wakeup signaling from a device
+ *  - Resume to Recovery to U0          USB 3.0 device resume
+ *  - Resume to U0                      USB 2.0 device resume
+ *  - U3 to Recovery to U0              Software resume of USB 3.0 device complete
+ *  - U3 to U0                          Software resume of USB 2.0 device complete
+ *  - U2 to U0                          L1 resume of USB 2.1 device complete
+ *  - U0 to U0 (???)                    L1 entry rejection by USB 2.1 device
+ *  - U0 to disabled                    L1 entry error with USB 2.1 device
+ *  - Any state to inactive             Error on USB 3.0 port
+ */
+#define PORT_PLC        (1 << 22)
+/* port configure error change - port failed to configure its link partner */
+#define PORT_CEC        (1 << 23)
+/* bit 24 reserved */
+/* wake on connect (enable) */
+#define PORT_WKCONN_E   (1 << 25)
+/* wake on disconnect (enable) */
+#define PORT_WKDISC_E   (1 << 26)
+/* wake on over-current (enable) */
+#define PORT_WKOC_E     (1 << 27)
+/* bits 28:29 reserved */
+/* true: device is removable - for USB 3.0 roothub emulation */
+#define PORT_DEV_REMOVE (1 << 30)
+/* Initiate a warm port reset - complete when PORT_WRC is '1' */
+#define PORT_WR         (1 << 31)
+
+/* Port Power Management Status and Control - port_power_base bitmasks */
+/* Inactivity timer value for transitions into U1, in microseconds.
+ * Timeout can be up to 127us.  0xFF means an infinite timeout.
+ */
+#define PORT_U1_TIMEOUT(p)      ((p) & 0xff)
+/* Inactivity timer value for transitions into U2 */
+#define PORT_U2_TIMEOUT(p)      (((p) & 0xff) << 8)
+/* Bits 24:31 for port testing */
+
+
+/**
+ * struct intr_reg - Interrupt Register Set
+ * @irq_pending:        IMAN - Interrupt Management Register.  Used to enable
+ *                      interrupts and check for pending interrupts.
+ * @irq_control:        IMOD - Interrupt Moderation Register.
+ *                      Used to throttle interrupts.
+ * @erst_size:          Number of segments in the Event Ring Segment Table (ERST).
+ * @erst_base:          ERST base address.
+ * @erst_dequeue:       Event ring dequeue pointer.
+ *
+ * Each interrupter (defined by a MSI-X vector) has an event ring and an Event
+ * Ring Segment Table (ERST) associated with it.  The event ring is comprised of
+ * multiple segments of the same size.  The HC places events on the ring and
+ * "updates the Cycle bit in the TRBs to indicate to software the current
+ * position of the Enqueue Pointer." The HCD (Linux) processes those events and
+ * updates the dequeue pointer.
+ */
+struct intr_reg {
+        u32     irq_pending;
+        u32     irq_control;
+        u32     erst_size;
+        u32     rsvd;
+        u32     erst_base[2];
+        u32     erst_dequeue[2];
+} __attribute__ ((packed));
+
+#define ER_IRQ_PENDING(p)       ((p) & 0x1)
+#define ER_IRQ_ENABLE(p)        ((p) | 0x2)
+/* Preserve bits 16:31 of erst_size */
+#define ERST_SIZE_MASK  (0xffff<<16)
+
+/**
+ * struct xhci_run_regs
+ * @microframe_index:
+ *              MFINDEX - current microframe number
+ *
+ * Section 5.5 Host Controller Runtime Registers:
+ * "Software should read and write these registers using only Dword (32 bit)
+ * or larger accesses"
+ */
+struct xhci_run_regs {
+        u32     microframe_index;
+        u32     rsvd[7];
+        struct intr_reg ir_set[128];
+} __attribute__ ((packed));
+
+
+/* There is one ehci_hci structure per controller */
+struct xhci_hcd {
+        /* glue to PCI and HCD framework */
+        struct xhci_cap_regs __iomem *cap_regs;
+        struct xhci_op_regs __iomem *op_regs;
+        struct xhci_run_regs __iomem *run_regs;
+
+        /* Cached register copies of read-only HC data */
+        __u32           hcs_params1;
+        __u32           hcs_params2;
+        __u32           hcs_params3;
+        __u32           hcc_params;
+
+        spinlock_t      lock;
+
+        /* packed release number */
+        u8              sbrn;
+        u16             hci_version;
+        u8              max_slots;
+        u8              max_interrupters;
+        u8              max_ports;
+        u8              isoc_threshold;
+        int             event_ring_max;
+        int             addr_64;
+        int             page_size;
+};
+
+/* convert between an HCD pointer and the corresponding EHCI_HCD */
+static inline struct xhci_hcd *hcd_to_xhci(struct usb_hcd *hcd)
+{
+        return (struct xhci_hcd *) (hcd->hcd_priv);
+}
+
+static inline struct usb_hcd *xhci_to_hcd(struct xhci_hcd *xhci)
+{
+        return container_of((void *) xhci, struct usb_hcd, hcd_priv);
+}
+
+#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
+#define XHCI_DEBUG      1
+#else
+#define XHCI_DEBUG      0
+#endif
+
+#define xhci_dbg(xhci, fmt, args...) \
+        do { if (XHCI_DEBUG) dev_dbg(xhci_to_hcd(xhci)->self.controller , fmt , ## args); } while (0)
+#define xhci_info(xhci, fmt, args...) \
+        do { if (XHCI_DEBUG) dev_info(xhci_to_hcd(xhci)->self.controller , fmt , ## args); } while (0)
+#define xhci_err(xhci, fmt, args...) \
+        dev_err(xhci_to_hcd(xhci)->self.controller , fmt , ## args)
+#define xhci_warn(xhci, fmt, args...) \
+        dev_warn(xhci_to_hcd(xhci)->self.controller , fmt , ## args)
+
+/* TODO: copied from ehci.h - can be refactored? */
+/* xHCI spec says all registers are little endian */
+static inline unsigned int xhci_readl(const struct xhci_hcd *xhci,
+                __u32 __iomem *regs)
+{
+        return readl(regs);
+}
+static inline void xhci_writel(const struct xhci_hcd *xhci,
+                const unsigned int val, __u32 __iomem *regs)
+{
+        if (!in_interrupt())
+                xhci_dbg(xhci, "`MEM_WRITE_DWORD(3'b000, 32'h%0x, 32'h%0x, 4'hf);\n",
+                                (unsigned int) regs, val);
+        writel(val, regs);
+}
+
+#endif /* __LINUX_XHCI_HCD_H */