drivers/usb/host/xhci-dbg.c - kernel/windcharger - Git at Google

 /*
  * 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 %p:\n",
 			xhci->cap_regs);
 	temp = xhci_readl(xhci, &xhci->cap_regs->hc_capbase);
 	xhci_dbg(xhci, "// @%p = 0x%x (CAPLENGTH AND HCIVERSION)\n",
 			&xhci->cap_regs->hc_capbase, 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 %p:\n", xhci->op_regs);

 	temp = xhci_readl(xhci, &xhci->cap_regs->run_regs_off);
 	xhci_dbg(xhci, "// @%p = 0x%x RTSOFF\n",
 			&xhci->cap_regs->run_regs_off,
 			(unsigned int) temp & RTSOFF_MASK);
 	xhci_dbg(xhci, "// xHCI runtime registers at %p:\n", xhci->run_regs);

 	temp = xhci_readl(xhci, &xhci->cap_regs->db_off);
 	xhci_dbg(xhci, "// @%p = 0x%x DBOFF\n", &xhci->cap_regs->db_off, temp);
 	xhci_dbg(xhci, "// Doorbell array at %p:\n", xhci->dba);
 }

 static void xhci_print_cap_regs(struct xhci_hcd *xhci)
 {
 	u32 temp;

 	xhci_dbg(xhci, "xHCI capability registers at %p:\n", 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);
 }

 static 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 " : "");
 }

 static 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");
 }

 static void xhci_print_op_regs(struct xhci_hcd *xhci)
 {
 	xhci_dbg(xhci, "xHCI operational registers at %p:\n", xhci->op_regs);
 	xhci_print_command_reg(xhci);
 	xhci_print_status(xhci);
 }

 static void xhci_print_ports(struct xhci_hcd *xhci)
 {
 	u32 __iomem *addr;
 	int i, j;
 	int ports;
 	char *names[NUM_PORT_REGS] = {
 		"status",
 		"power",
 		"link",
 		"reserved",
 	};

 	ports = HCS_MAX_PORTS(xhci->hcs_params1);
 	addr = &xhci->op_regs->port_status_base;
 	for (i = 0; i < ports; i++) {
 		for (j = 0; j < NUM_PORT_REGS; ++j) {
 			xhci_dbg(xhci, "%p port %s reg = 0x%x\n",
 					addr, names[j],
 					(unsigned int) xhci_readl(xhci, addr));
 			addr++;
 		}
 	}
 }

 void xhci_print_ir_set(struct xhci_hcd *xhci, struct xhci_intr_reg *ir_set, int set_num)
 {
 	void *addr;
 	u32 temp;
 	u64 temp_64;

 	addr = &ir_set->irq_pending;
 	temp = xhci_readl(xhci, addr);
 	if (temp == XHCI_INIT_VALUE)
 		return;

 	xhci_dbg(xhci, "  %p: ir_set[%i]\n", ir_set, set_num);

 	xhci_dbg(xhci, "  %p: ir_set.pending = 0x%x\n", addr,
 			(unsigned int)temp);

 	addr = &ir_set->irq_control;
 	temp = xhci_readl(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.control = 0x%x\n", addr,
 			(unsigned int)temp);

 	addr = &ir_set->erst_size;
 	temp = xhci_readl(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.erst_size = 0x%x\n", addr,
 			(unsigned int)temp);

 	addr = &ir_set->rsvd;
 	temp = xhci_readl(xhci, addr);
 	if (temp != XHCI_INIT_VALUE)
 		xhci_dbg(xhci, "  WARN: %p: ir_set.rsvd = 0x%x\n",
 				addr, (unsigned int)temp);

 	addr = &ir_set->erst_base;
 	temp_64 = xhci_read_64(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.erst_base = @%08llx\n",
 			addr, temp_64);

 	addr = &ir_set->erst_dequeue;
 	temp_64 = xhci_read_64(xhci, addr);
 	xhci_dbg(xhci, "  %p: ir_set.erst_dequeue = @%08llx\n",
 			addr, temp_64);
 }

 void xhci_print_run_regs(struct xhci_hcd *xhci)
 {
 	u32 temp;
 	int i;

 	xhci_dbg(xhci, "xHCI runtime registers at %p:\n", xhci->run_regs);
 	temp = xhci_readl(xhci, &xhci->run_regs->microframe_index);
 	xhci_dbg(xhci, "  %p: Microframe index = 0x%x\n",
 			&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: %p: Rsvd[%i] = 0x%x\n",
 					&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);
 	xhci_print_ports(xhci);
 }

 void xhci_print_trb_offsets(struct xhci_hcd *xhci, union xhci_trb *trb)
 {
 	int i;
 	for (i = 0; i < 4; ++i)
 		xhci_dbg(xhci, "Offset 0x%x = 0x%x\n",
 				i*4, trb->generic.field[i]);
 }

 /**
  * Debug a transfer request block (TRB).
  */
 void xhci_debug_trb(struct xhci_hcd *xhci, union xhci_trb *trb)
 {
 	u64	address;
 	u32	type = xhci_readl(xhci, &trb->link.control) & TRB_TYPE_BITMASK;

 	switch (type) {
 	case TRB_TYPE(TRB_LINK):
 		xhci_dbg(xhci, "Link TRB:\n");
 		xhci_print_trb_offsets(xhci, trb);

 		address = trb->link.segment_ptr;
 		xhci_dbg(xhci, "Next ring segment DMA address = 0x%llx\n", address);

 		xhci_dbg(xhci, "Interrupter target = 0x%x\n",
 				GET_INTR_TARGET(trb->link.intr_target));
 		xhci_dbg(xhci, "Cycle bit = %u\n",
 				(unsigned int) (trb->link.control & TRB_CYCLE));
 		xhci_dbg(xhci, "Toggle cycle bit = %u\n",
 				(unsigned int) (trb->link.control & LINK_TOGGLE));
 		xhci_dbg(xhci, "No Snoop bit = %u\n",
 				(unsigned int) (trb->link.control & TRB_NO_SNOOP));
 		break;
 	case TRB_TYPE(TRB_TRANSFER):
 		address = trb->trans_event.buffer;
 		/*
 		 * FIXME: look at flags to figure out if it's an address or if
 		 * the data is directly in the buffer field.
 		 */
 		xhci_dbg(xhci, "DMA address or buffer contents= %llu\n", address);
 		break;
 	case TRB_TYPE(TRB_COMPLETION):
 		address = trb->event_cmd.cmd_trb;
 		xhci_dbg(xhci, "Command TRB pointer = %llu\n", address);
 		xhci_dbg(xhci, "Completion status = %u\n",
 				(unsigned int) GET_COMP_CODE(trb->event_cmd.status));
 		xhci_dbg(xhci, "Flags = 0x%x\n", (unsigned int) trb->event_cmd.flags);
 		break;
 	default:
 		xhci_dbg(xhci, "Unknown TRB with TRB type ID %u\n",
 				(unsigned int) type>>10);
 		xhci_print_trb_offsets(xhci, trb);
 		break;
 	}
 }

 /**
  * Debug a segment with an xHCI ring.
  *
  * @return The Link TRB of the segment, or NULL if there is no Link TRB
  * (which is a bug, since all segments must have a Link TRB).
  *
  * Prints out all TRBs in the segment, even those after the Link TRB.
  *
  * XXX: should we print out TRBs that the HC owns?  As long as we don't
  * write, that should be fine...  We shouldn't expect that the memory pointed to
  * by the TRB is valid at all.  Do we care about ones the HC owns?  Probably,
  * for HC debugging.
  */
 void xhci_debug_segment(struct xhci_hcd *xhci, struct xhci_segment *seg)
 {
 	int i;
 	u32 addr = (u32) seg->dma;
 	union xhci_trb *trb = seg->trbs;

 	for (i = 0; i < TRBS_PER_SEGMENT; ++i) {
 		trb = &seg->trbs[i];
 		xhci_dbg(xhci, "@%08x %08x %08x %08x %08x\n", addr,
 				lower_32_bits(trb->link.segment_ptr),
 				upper_32_bits(trb->link.segment_ptr),
 				(unsigned int) trb->link.intr_target,
 				(unsigned int) trb->link.control);
 		addr += sizeof(*trb);
 	}
 }

 void xhci_dbg_ring_ptrs(struct xhci_hcd *xhci, struct xhci_ring *ring)
 {
 	xhci_dbg(xhci, "Ring deq = %p (virt), 0x%llx (dma)\n",
 			ring->dequeue,
 			(unsigned long long)xhci_trb_virt_to_dma(ring->deq_seg,
 							    ring->dequeue));
 	xhci_dbg(xhci, "Ring deq updated %u times\n",
 			ring->deq_updates);
 	xhci_dbg(xhci, "Ring enq = %p (virt), 0x%llx (dma)\n",
 			ring->enqueue,
 			(unsigned long long)xhci_trb_virt_to_dma(ring->enq_seg,
 							    ring->enqueue));
 	xhci_dbg(xhci, "Ring enq updated %u times\n",
 			ring->enq_updates);
 }

 /**
  * Debugging for an xHCI ring, which is a queue broken into multiple segments.
  *
  * Print out each segment in the ring.  Check that the DMA address in
  * each link segment actually matches the segment's stored DMA address.
  * Check that the link end bit is only set at the end of the ring.
  * Check that the dequeue and enqueue pointers point to real data in this ring
  * (not some other ring).
  */
 void xhci_debug_ring(struct xhci_hcd *xhci, struct xhci_ring *ring)
 {
 	/* FIXME: Throw an error if any segment doesn't have a Link TRB */
 	struct xhci_segment *seg;
 	struct xhci_segment *first_seg = ring->first_seg;
 	xhci_debug_segment(xhci, first_seg);

 	if (!ring->enq_updates && !ring->deq_updates) {
 		xhci_dbg(xhci, "  Ring has not been updated\n");
 		return;
 	}
 	for (seg = first_seg->next; seg != first_seg; seg = seg->next)
 		xhci_debug_segment(xhci, seg);
 }

 void xhci_dbg_erst(struct xhci_hcd *xhci, struct xhci_erst *erst)
 {
 	u32 addr = (u32) erst->erst_dma_addr;
 	int i;
 	struct xhci_erst_entry *entry;

 	for (i = 0; i < erst->num_entries; ++i) {
 		entry = &erst->entries[i];
 		xhci_dbg(xhci, "@%08x %08x %08x %08x %08x\n",
 				(unsigned int) addr,
 				lower_32_bits(entry->seg_addr),
 				upper_32_bits(entry->seg_addr),
 				(unsigned int) entry->seg_size,
 				(unsigned int) entry->rsvd);
 		addr += sizeof(*entry);
 	}
 }

 void xhci_dbg_cmd_ptrs(struct xhci_hcd *xhci)
 {
 	u64 val;

 	val = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
 	xhci_dbg(xhci, "// xHC command ring deq ptr low bits + flags = @%08x\n",
 			lower_32_bits(val));
 	xhci_dbg(xhci, "// xHC command ring deq ptr high bits = @%08x\n",
 			upper_32_bits(val));
 }

 /* Print the last 32 bytes for 64-byte contexts */
 static void dbg_rsvd64(struct xhci_hcd *xhci, u64 *ctx, dma_addr_t dma)
 {
 	int i;
 	for (i = 0; i < 4; ++i) {
 		xhci_dbg(xhci, "@%p (virt) @%08llx "
 			 "(dma) %#08llx - rsvd64[%d]\n",
 			 &ctx[4 + i], (unsigned long long)dma,
 			 ctx[4 + i], i);
 		dma += 8;
 	}
 }

 void xhci_dbg_slot_ctx(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx)
 {
 	/* Fields are 32 bits wide, DMA addresses are in bytes */
 	int field_size = 32 / 8;
 	int i;

 	struct xhci_slot_ctx *slot_ctx = xhci_get_slot_ctx(xhci, ctx);
 	dma_addr_t dma = ctx->dma + ((unsigned long)slot_ctx - (unsigned long)ctx);
 	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

 	xhci_dbg(xhci, "Slot Context:\n");
 	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_info\n",
 			&slot_ctx->dev_info,
 			(unsigned long long)dma, slot_ctx->dev_info);
 	dma += field_size;
 	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_info2\n",
 			&slot_ctx->dev_info2,
 			(unsigned long long)dma, slot_ctx->dev_info2);
 	dma += field_size;
 	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - tt_info\n",
 			&slot_ctx->tt_info,
 			(unsigned long long)dma, slot_ctx->tt_info);
 	dma += field_size;
 	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_state\n",
 			&slot_ctx->dev_state,
 			(unsigned long long)dma, slot_ctx->dev_state);
 	dma += field_size;
 	for (i = 0; i < 4; ++i) {
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd[%d]\n",
 				&slot_ctx->reserved[i], (unsigned long long)dma,
 				slot_ctx->reserved[i], i);
 		dma += field_size;
 	}

 	if (csz)
 		dbg_rsvd64(xhci, (u64 *)slot_ctx, dma);
 }

 void xhci_dbg_ep_ctx(struct xhci_hcd *xhci,
 		     struct xhci_container_ctx *ctx,
 		     unsigned int last_ep)
 {
 	int i, j;
 	int last_ep_ctx = 31;
 	/* Fields are 32 bits wide, DMA addresses are in bytes */
 	int field_size = 32 / 8;
 	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

 	if (last_ep < 31)
 		last_ep_ctx = last_ep + 1;
 	for (i = 0; i < last_ep_ctx; ++i) {
 		struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, ctx, i);
 		dma_addr_t dma = ctx->dma +
 			((unsigned long)ep_ctx - (unsigned long)ctx);

 		xhci_dbg(xhci, "Endpoint %02d Context:\n", i);
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - ep_info\n",
 				&ep_ctx->ep_info,
 				(unsigned long long)dma, ep_ctx->ep_info);
 		dma += field_size;
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - ep_info2\n",
 				&ep_ctx->ep_info2,
 				(unsigned long long)dma, ep_ctx->ep_info2);
 		dma += field_size;
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08llx - deq\n",
 				&ep_ctx->deq,
 				(unsigned long long)dma, ep_ctx->deq);
 		dma += 2*field_size;
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - tx_info\n",
 				&ep_ctx->tx_info,
 				(unsigned long long)dma, ep_ctx->tx_info);
 		dma += field_size;
 		for (j = 0; j < 3; ++j) {
 			xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd[%d]\n",
 					&ep_ctx->reserved[j],
 					(unsigned long long)dma,
 					ep_ctx->reserved[j], j);
 			dma += field_size;
 		}

 		if (csz)
 			dbg_rsvd64(xhci, (u64 *)ep_ctx, dma);
 	}
 }

 void xhci_dbg_ctx(struct xhci_hcd *xhci,
 		  struct xhci_container_ctx *ctx,
 		  unsigned int last_ep)
 {
 	int i;
 	/* Fields are 32 bits wide, DMA addresses are in bytes */
 	int field_size = 32 / 8;
 	struct xhci_slot_ctx *slot_ctx;
 	dma_addr_t dma = ctx->dma;
 	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

 	if (ctx->type == XHCI_CTX_TYPE_INPUT) {
 		struct xhci_input_control_ctx *ctrl_ctx =
 			xhci_get_input_control_ctx(xhci, ctx);
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - drop flags\n",
 			 &ctrl_ctx->drop_flags, (unsigned long long)dma,
 			 ctrl_ctx->drop_flags);
 		dma += field_size;
 		xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - add flags\n",
 			 &ctrl_ctx->add_flags, (unsigned long long)dma,
 			 ctrl_ctx->add_flags);
 		dma += field_size;
 		for (i = 0; i < 6; ++i) {
 			xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd2[%d]\n",
 				 &ctrl_ctx->rsvd2[i], (unsigned long long)dma,
 				 ctrl_ctx->rsvd2[i], i);
 			dma += field_size;
 		}

 		if (csz)
 			dbg_rsvd64(xhci, (u64 *)ctrl_ctx, dma);
 	}

 	slot_ctx = xhci_get_slot_ctx(xhci, ctx);
 	xhci_dbg_slot_ctx(xhci, ctx);
 	xhci_dbg_ep_ctx(xhci, ctx, last_ep);
 }
	/*
	* 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 %p:\n",
	xhci->cap_regs);
	temp = xhci_readl(xhci, &xhci->cap_regs->hc_capbase);
	xhci_dbg(xhci, "// @%p = 0x%x (CAPLENGTH AND HCIVERSION)\n",
	&xhci->cap_regs->hc_capbase, 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 %p:\n", xhci->op_regs);

	temp = xhci_readl(xhci, &xhci->cap_regs->run_regs_off);
	xhci_dbg(xhci, "// @%p = 0x%x RTSOFF\n",
	&xhci->cap_regs->run_regs_off,
	(unsigned int) temp & RTSOFF_MASK);
	xhci_dbg(xhci, "// xHCI runtime registers at %p:\n", xhci->run_regs);

	temp = xhci_readl(xhci, &xhci->cap_regs->db_off);
	xhci_dbg(xhci, "// @%p = 0x%x DBOFF\n", &xhci->cap_regs->db_off, temp);
	xhci_dbg(xhci, "// Doorbell array at %p:\n", xhci->dba);
	}

	static void xhci_print_cap_regs(struct xhci_hcd *xhci)
	{
	u32 temp;

	xhci_dbg(xhci, "xHCI capability registers at %p:\n", 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);
	}

	static 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 " : "");
	}

	static 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");
	}

	static void xhci_print_op_regs(struct xhci_hcd *xhci)
	{
	xhci_dbg(xhci, "xHCI operational registers at %p:\n", xhci->op_regs);
	xhci_print_command_reg(xhci);
	xhci_print_status(xhci);
	}

	static void xhci_print_ports(struct xhci_hcd *xhci)
	{
	u32 __iomem *addr;
	int i, j;
	int ports;
	char *names[NUM_PORT_REGS] = {
	"status",
	"power",
	"link",
	"reserved",
	};

	ports = HCS_MAX_PORTS(xhci->hcs_params1);
	addr = &xhci->op_regs->port_status_base;
	for (i = 0; i < ports; i++) {
	for (j = 0; j < NUM_PORT_REGS; ++j) {
	xhci_dbg(xhci, "%p port %s reg = 0x%x\n",
	addr, names[j],
	(unsigned int) xhci_readl(xhci, addr));
	addr++;
	}
	}
	}

	void xhci_print_ir_set(struct xhci_hcd xhci, struct xhci_intr_reg ir_set, int set_num)
	{
	void *addr;
	u32 temp;
	u64 temp_64;

	addr = &ir_set->irq_pending;
	temp = xhci_readl(xhci, addr);
	if (temp == XHCI_INIT_VALUE)
	return;

	xhci_dbg(xhci, " %p: ir_set[%i]\n", ir_set, set_num);

	xhci_dbg(xhci, " %p: ir_set.pending = 0x%x\n", addr,
	(unsigned int)temp);

	addr = &ir_set->irq_control;
	temp = xhci_readl(xhci, addr);
	xhci_dbg(xhci, " %p: ir_set.control = 0x%x\n", addr,
	(unsigned int)temp);

	addr = &ir_set->erst_size;
	temp = xhci_readl(xhci, addr);
	xhci_dbg(xhci, " %p: ir_set.erst_size = 0x%x\n", addr,
	(unsigned int)temp);

	addr = &ir_set->rsvd;
	temp = xhci_readl(xhci, addr);
	if (temp != XHCI_INIT_VALUE)
	xhci_dbg(xhci, " WARN: %p: ir_set.rsvd = 0x%x\n",
	addr, (unsigned int)temp);

	addr = &ir_set->erst_base;
	temp_64 = xhci_read_64(xhci, addr);
	xhci_dbg(xhci, " %p: ir_set.erst_base = @%08llx\n",
	addr, temp_64);

	addr = &ir_set->erst_dequeue;
	temp_64 = xhci_read_64(xhci, addr);
	xhci_dbg(xhci, " %p: ir_set.erst_dequeue = @%08llx\n",
	addr, temp_64);
	}

	void xhci_print_run_regs(struct xhci_hcd *xhci)
	{
	u32 temp;
	int i;

	xhci_dbg(xhci, "xHCI runtime registers at %p:\n", xhci->run_regs);
	temp = xhci_readl(xhci, &xhci->run_regs->microframe_index);
	xhci_dbg(xhci, " %p: Microframe index = 0x%x\n",
	&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: %p: Rsvd[%i] = 0x%x\n",
	&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);
	xhci_print_ports(xhci);
	}

	void xhci_print_trb_offsets(struct xhci_hcd xhci, union xhci_trb trb)
	{
	int i;
	for (i = 0; i < 4; ++i)
	xhci_dbg(xhci, "Offset 0x%x = 0x%x\n",
	i*4, trb->generic.field[i]);
	}

	/**
	* Debug a transfer request block (TRB).
	*/
	void xhci_debug_trb(struct xhci_hcd xhci, union xhci_trb trb)
	{
	u64 address;
	u32 type = xhci_readl(xhci, &trb->link.control) & TRB_TYPE_BITMASK;

	switch (type) {
	case TRB_TYPE(TRB_LINK):
	xhci_dbg(xhci, "Link TRB:\n");
	xhci_print_trb_offsets(xhci, trb);

	address = trb->link.segment_ptr;
	xhci_dbg(xhci, "Next ring segment DMA address = 0x%llx\n", address);

	xhci_dbg(xhci, "Interrupter target = 0x%x\n",
	GET_INTR_TARGET(trb->link.intr_target));
	xhci_dbg(xhci, "Cycle bit = %u\n",
	(unsigned int) (trb->link.control & TRB_CYCLE));
	xhci_dbg(xhci, "Toggle cycle bit = %u\n",
	(unsigned int) (trb->link.control & LINK_TOGGLE));
	xhci_dbg(xhci, "No Snoop bit = %u\n",
	(unsigned int) (trb->link.control & TRB_NO_SNOOP));
	break;
	case TRB_TYPE(TRB_TRANSFER):
	address = trb->trans_event.buffer;
	/*
	* FIXME: look at flags to figure out if it's an address or if
	* the data is directly in the buffer field.
	*/
	xhci_dbg(xhci, "DMA address or buffer contents= %llu\n", address);
	break;
	case TRB_TYPE(TRB_COMPLETION):
	address = trb->event_cmd.cmd_trb;
	xhci_dbg(xhci, "Command TRB pointer = %llu\n", address);
	xhci_dbg(xhci, "Completion status = %u\n",
	(unsigned int) GET_COMP_CODE(trb->event_cmd.status));
	xhci_dbg(xhci, "Flags = 0x%x\n", (unsigned int) trb->event_cmd.flags);
	break;
	default:
	xhci_dbg(xhci, "Unknown TRB with TRB type ID %u\n",
	(unsigned int) type>>10);
	xhci_print_trb_offsets(xhci, trb);
	break;
	}
	}

	/**
	* Debug a segment with an xHCI ring.
	*
	* @return The Link TRB of the segment, or NULL if there is no Link TRB
	* (which is a bug, since all segments must have a Link TRB).
	*
	* Prints out all TRBs in the segment, even those after the Link TRB.
	*
	* XXX: should we print out TRBs that the HC owns? As long as we don't
	* write, that should be fine... We shouldn't expect that the memory pointed to
	* by the TRB is valid at all. Do we care about ones the HC owns? Probably,
	* for HC debugging.
	*/
	void xhci_debug_segment(struct xhci_hcd xhci, struct xhci_segment seg)
	{
	int i;
	u32 addr = (u32) seg->dma;
	union xhci_trb *trb = seg->trbs;

	for (i = 0; i < TRBS_PER_SEGMENT; ++i) {
	trb = &seg->trbs[i];
	xhci_dbg(xhci, "@%08x %08x %08x %08x %08x\n", addr,
	lower_32_bits(trb->link.segment_ptr),
	upper_32_bits(trb->link.segment_ptr),
	(unsigned int) trb->link.intr_target,
	(unsigned int) trb->link.control);
	addr += sizeof(*trb);
	}
	}

	void xhci_dbg_ring_ptrs(struct xhci_hcd xhci, struct xhci_ring ring)
	{
	xhci_dbg(xhci, "Ring deq = %p (virt), 0x%llx (dma)\n",
	ring->dequeue,
	(unsigned long long)xhci_trb_virt_to_dma(ring->deq_seg,
	ring->dequeue));
	xhci_dbg(xhci, "Ring deq updated %u times\n",
	ring->deq_updates);
	xhci_dbg(xhci, "Ring enq = %p (virt), 0x%llx (dma)\n",
	ring->enqueue,
	(unsigned long long)xhci_trb_virt_to_dma(ring->enq_seg,
	ring->enqueue));
	xhci_dbg(xhci, "Ring enq updated %u times\n",
	ring->enq_updates);
	}

	/**
	* Debugging for an xHCI ring, which is a queue broken into multiple segments.
	*
	* Print out each segment in the ring. Check that the DMA address in
	* each link segment actually matches the segment's stored DMA address.
	* Check that the link end bit is only set at the end of the ring.
	* Check that the dequeue and enqueue pointers point to real data in this ring
	* (not some other ring).
	*/
	void xhci_debug_ring(struct xhci_hcd xhci, struct xhci_ring ring)
	{
	/* FIXME: Throw an error if any segment doesn't have a Link TRB */
	struct xhci_segment *seg;
	struct xhci_segment *first_seg = ring->first_seg;
	xhci_debug_segment(xhci, first_seg);

	if (!ring->enq_updates && !ring->deq_updates) {
	xhci_dbg(xhci, " Ring has not been updated\n");
	return;
	}
	for (seg = first_seg->next; seg != first_seg; seg = seg->next)
	xhci_debug_segment(xhci, seg);
	}

	void xhci_dbg_erst(struct xhci_hcd xhci, struct xhci_erst erst)
	{
	u32 addr = (u32) erst->erst_dma_addr;
	int i;
	struct xhci_erst_entry *entry;

	for (i = 0; i < erst->num_entries; ++i) {
	entry = &erst->entries[i];
	xhci_dbg(xhci, "@%08x %08x %08x %08x %08x\n",
	(unsigned int) addr,
	lower_32_bits(entry->seg_addr),
	upper_32_bits(entry->seg_addr),
	(unsigned int) entry->seg_size,
	(unsigned int) entry->rsvd);
	addr += sizeof(*entry);
	}
	}

	void xhci_dbg_cmd_ptrs(struct xhci_hcd *xhci)
	{
	u64 val;

	val = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
	xhci_dbg(xhci, "// xHC command ring deq ptr low bits + flags = @%08x\n",
	lower_32_bits(val));
	xhci_dbg(xhci, "// xHC command ring deq ptr high bits = @%08x\n",
	upper_32_bits(val));
	}

	/* Print the last 32 bytes for 64-byte contexts */
	static void dbg_rsvd64(struct xhci_hcd xhci, u64 ctx, dma_addr_t dma)
	{
	int i;
	for (i = 0; i < 4; ++i) {
	xhci_dbg(xhci, "@%p (virt) @%08llx "
	"(dma) %#08llx - rsvd64[%d]\n",
	&ctx[4 + i], (unsigned long long)dma,
	ctx[4 + i], i);
	dma += 8;
	}
	}

	void xhci_dbg_slot_ctx(struct xhci_hcd xhci, struct xhci_container_ctx ctx)
	{
	/* Fields are 32 bits wide, DMA addresses are in bytes */
	int field_size = 32 / 8;
	int i;

	struct xhci_slot_ctx *slot_ctx = xhci_get_slot_ctx(xhci, ctx);
	dma_addr_t dma = ctx->dma + ((unsigned long)slot_ctx - (unsigned long)ctx);
	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

	xhci_dbg(xhci, "Slot Context:\n");
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_info\n",
	&slot_ctx->dev_info,
	(unsigned long long)dma, slot_ctx->dev_info);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_info2\n",
	&slot_ctx->dev_info2,
	(unsigned long long)dma, slot_ctx->dev_info2);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - tt_info\n",
	&slot_ctx->tt_info,
	(unsigned long long)dma, slot_ctx->tt_info);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - dev_state\n",
	&slot_ctx->dev_state,
	(unsigned long long)dma, slot_ctx->dev_state);
	dma += field_size;
	for (i = 0; i < 4; ++i) {
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd[%d]\n",
	&slot_ctx->reserved[i], (unsigned long long)dma,
	slot_ctx->reserved[i], i);
	dma += field_size;
	}

	if (csz)
	dbg_rsvd64(xhci, (u64 *)slot_ctx, dma);
	}

	void xhci_dbg_ep_ctx(struct xhci_hcd *xhci,
	struct xhci_container_ctx *ctx,
	unsigned int last_ep)
	{
	int i, j;
	int last_ep_ctx = 31;
	/* Fields are 32 bits wide, DMA addresses are in bytes */
	int field_size = 32 / 8;
	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

	if (last_ep < 31)
	last_ep_ctx = last_ep + 1;
	for (i = 0; i < last_ep_ctx; ++i) {
	struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, ctx, i);
	dma_addr_t dma = ctx->dma +
	((unsigned long)ep_ctx - (unsigned long)ctx);

	xhci_dbg(xhci, "Endpoint %02d Context:\n", i);
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - ep_info\n",
	&ep_ctx->ep_info,
	(unsigned long long)dma, ep_ctx->ep_info);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - ep_info2\n",
	&ep_ctx->ep_info2,
	(unsigned long long)dma, ep_ctx->ep_info2);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08llx - deq\n",
	&ep_ctx->deq,
	(unsigned long long)dma, ep_ctx->deq);
	dma += 2*field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - tx_info\n",
	&ep_ctx->tx_info,
	(unsigned long long)dma, ep_ctx->tx_info);
	dma += field_size;
	for (j = 0; j < 3; ++j) {
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd[%d]\n",
	&ep_ctx->reserved[j],
	(unsigned long long)dma,
	ep_ctx->reserved[j], j);
	dma += field_size;
	}

	if (csz)
	dbg_rsvd64(xhci, (u64 *)ep_ctx, dma);
	}
	}

	void xhci_dbg_ctx(struct xhci_hcd *xhci,
	struct xhci_container_ctx *ctx,
	unsigned int last_ep)
	{
	int i;
	/* Fields are 32 bits wide, DMA addresses are in bytes */
	int field_size = 32 / 8;
	struct xhci_slot_ctx *slot_ctx;
	dma_addr_t dma = ctx->dma;
	int csz = HCC_64BYTE_CONTEXT(xhci->hcc_params);

	if (ctx->type == XHCI_CTX_TYPE_INPUT) {
	struct xhci_input_control_ctx *ctrl_ctx =
	xhci_get_input_control_ctx(xhci, ctx);
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - drop flags\n",
	&ctrl_ctx->drop_flags, (unsigned long long)dma,
	ctrl_ctx->drop_flags);
	dma += field_size;
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - add flags\n",
	&ctrl_ctx->add_flags, (unsigned long long)dma,
	ctrl_ctx->add_flags);
	dma += field_size;
	for (i = 0; i < 6; ++i) {
	xhci_dbg(xhci, "@%p (virt) @%08llx (dma) %#08x - rsvd2[%d]\n",
	&ctrl_ctx->rsvd2[i], (unsigned long long)dma,
	ctrl_ctx->rsvd2[i], i);
	dma += field_size;
	}

	if (csz)
	dbg_rsvd64(xhci, (u64 *)ctrl_ctx, dma);
	}

	slot_ctx = xhci_get_slot_ctx(xhci, ctx);
	xhci_dbg_slot_ctx(xhci, ctx);
	xhci_dbg_ep_ctx(xhci, ctx, last_ep);
	}