diff options
Diffstat (limited to 'drivers/usb/host/xhci-dbgcap.c')
| -rw-r--r-- | drivers/usb/host/xhci-dbgcap.c | 1435 |
1 files changed, 1435 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c new file mode 100644 index 000000000000..9da4f3b452cb --- /dev/null +++ b/drivers/usb/host/xhci-dbgcap.c @@ -0,0 +1,1435 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * xhci-dbgcap.c - xHCI debug capability support + * + * Copyright (C) 2017 Intel Corporation + * + * Author: Lu Baolu <baolu.lu@linux.intel.com> + */ +#include <linux/bug.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/kstrtox.h> +#include <linux/list.h> +#include <linux/nls.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/string.h> +#include <linux/sysfs.h> +#include <linux/types.h> +#include <linux/workqueue.h> + +#include <linux/io-64-nonatomic-lo-hi.h> + +#include <asm/byteorder.h> + +#include "xhci.h" +#include "xhci-trace.h" +#include "xhci-dbgcap.h" + +static void dbc_free_ctx(struct device *dev, struct xhci_container_ctx *ctx) +{ + if (!ctx) + return; + dma_free_coherent(dev, ctx->size, ctx->bytes, ctx->dma); + kfree(ctx); +} + +/* we use only one segment for DbC rings */ +static void dbc_ring_free(struct device *dev, struct xhci_ring *ring) +{ + if (!ring) + return; + + if (ring->first_seg) { + dma_free_coherent(dev, TRB_SEGMENT_SIZE, + ring->first_seg->trbs, + ring->first_seg->dma); + kfree(ring->first_seg); + } + kfree(ring); +} + +static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings) +{ + struct usb_string_descriptor *s_desc; + u32 string_length; + + /* Serial string: */ + s_desc = (struct usb_string_descriptor *)strings->serial; + utf8s_to_utf16s(DBC_STRING_SERIAL, strlen(DBC_STRING_SERIAL), + UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, + DBC_MAX_STRING_LENGTH); + + s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2; + s_desc->bDescriptorType = USB_DT_STRING; + string_length = s_desc->bLength; + string_length <<= 8; + + /* Product string: */ + s_desc = (struct usb_string_descriptor *)strings->product; + utf8s_to_utf16s(DBC_STRING_PRODUCT, strlen(DBC_STRING_PRODUCT), + UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, + DBC_MAX_STRING_LENGTH); + + s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2; + s_desc->bDescriptorType = USB_DT_STRING; + string_length += s_desc->bLength; + string_length <<= 8; + + /* Manufacture string: */ + s_desc = (struct usb_string_descriptor *)strings->manufacturer; + utf8s_to_utf16s(DBC_STRING_MANUFACTURER, + strlen(DBC_STRING_MANUFACTURER), + UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, + DBC_MAX_STRING_LENGTH); + + s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2; + s_desc->bDescriptorType = USB_DT_STRING; + string_length += s_desc->bLength; + string_length <<= 8; + + /* String0: */ + strings->string0[0] = 4; + strings->string0[1] = USB_DT_STRING; + strings->string0[2] = 0x09; + strings->string0[3] = 0x04; + string_length += 4; + + return string_length; +} + +static void xhci_dbc_init_ep_contexts(struct xhci_dbc *dbc) +{ + struct xhci_ep_ctx *ep_ctx; + unsigned int max_burst; + dma_addr_t deq; + + max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control)); + + /* Populate bulk out endpoint context: */ + ep_ctx = dbc_bulkout_ctx(dbc); + deq = dbc_bulkout_enq(dbc); + ep_ctx->ep_info = 0; + ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst); + ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state); + + /* Populate bulk in endpoint context: */ + ep_ctx = dbc_bulkin_ctx(dbc); + deq = dbc_bulkin_enq(dbc); + ep_ctx->ep_info = 0; + ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst); + ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state); +} + +static void xhci_dbc_init_contexts(struct xhci_dbc *dbc, u32 string_length) +{ + struct dbc_info_context *info; + u32 dev_info; + dma_addr_t dma; + + if (!dbc) + return; + + /* Populate info Context: */ + info = (struct dbc_info_context *)dbc->ctx->bytes; + dma = dbc->string_dma; + info->string0 = cpu_to_le64(dma); + info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH); + info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2); + info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3); + info->length = cpu_to_le32(string_length); + + /* Populate bulk in and out endpoint contexts: */ + xhci_dbc_init_ep_contexts(dbc); + + /* Set DbC context and info registers: */ + lo_hi_writeq(dbc->ctx->dma, &dbc->regs->dccp); + + dev_info = (dbc->idVendor << 16) | dbc->bInterfaceProtocol; + writel(dev_info, &dbc->regs->devinfo1); + + dev_info = (dbc->bcdDevice << 16) | dbc->idProduct; + writel(dev_info, &dbc->regs->devinfo2); +} + +static void xhci_dbc_giveback(struct dbc_request *req, int status) + __releases(&dbc->lock) + __acquires(&dbc->lock) +{ + struct xhci_dbc *dbc = req->dbc; + struct device *dev = dbc->dev; + + list_del_init(&req->list_pending); + req->trb_dma = 0; + req->trb = NULL; + + if (req->status == -EINPROGRESS) + req->status = status; + + trace_xhci_dbc_giveback_request(req); + + dma_unmap_single(dev, + req->dma, + req->length, + dbc_ep_dma_direction(req)); + + /* Give back the transfer request: */ + spin_unlock(&dbc->lock); + req->complete(dbc, req); + spin_lock(&dbc->lock); +} + +static void trb_to_noop(union xhci_trb *trb) +{ + trb->generic.field[0] = 0; + trb->generic.field[1] = 0; + trb->generic.field[2] = 0; + trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE); + trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP)); +} + +static void xhci_dbc_flush_single_request(struct dbc_request *req) +{ + trb_to_noop(req->trb); + xhci_dbc_giveback(req, -ESHUTDOWN); +} + +static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep) +{ + struct dbc_request *req, *tmp; + + list_for_each_entry_safe(req, tmp, &dep->list_pending, list_pending) + xhci_dbc_flush_single_request(req); +} + +static void xhci_dbc_flush_requests(struct xhci_dbc *dbc) +{ + xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_OUT]); + xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_IN]); +} + +struct dbc_request * +dbc_alloc_request(struct xhci_dbc *dbc, unsigned int direction, gfp_t flags) +{ + struct dbc_request *req; + + if (direction != BULK_IN && + direction != BULK_OUT) + return NULL; + + if (!dbc) + return NULL; + + req = kzalloc(sizeof(*req), flags); + if (!req) + return NULL; + + req->dbc = dbc; + INIT_LIST_HEAD(&req->list_pending); + INIT_LIST_HEAD(&req->list_pool); + req->direction = direction; + + trace_xhci_dbc_alloc_request(req); + + return req; +} + +void +dbc_free_request(struct dbc_request *req) +{ + trace_xhci_dbc_free_request(req); + + kfree(req); +} + +static void +xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1, + u32 field2, u32 field3, u32 field4) +{ + union xhci_trb *trb, *next; + + trb = ring->enqueue; + trb->generic.field[0] = cpu_to_le32(field1); + trb->generic.field[1] = cpu_to_le32(field2); + trb->generic.field[2] = cpu_to_le32(field3); + trb->generic.field[3] = cpu_to_le32(field4); + + trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic, + xhci_trb_virt_to_dma(ring->enq_seg, + ring->enqueue)); + ring->num_trbs_free--; + next = ++(ring->enqueue); + if (TRB_TYPE_LINK_LE32(next->link.control)) { + next->link.control ^= cpu_to_le32(TRB_CYCLE); + ring->enqueue = ring->enq_seg->trbs; + ring->cycle_state ^= 1; + } +} + +static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep, + struct dbc_request *req) +{ + u64 addr; + union xhci_trb *trb; + unsigned int num_trbs; + struct xhci_dbc *dbc = req->dbc; + struct xhci_ring *ring = dep->ring; + u32 length, control, cycle; + + num_trbs = count_trbs(req->dma, req->length); + WARN_ON(num_trbs != 1); + if (ring->num_trbs_free < num_trbs) + return -EBUSY; + + addr = req->dma; + trb = ring->enqueue; + cycle = ring->cycle_state; + length = TRB_LEN(req->length); + control = TRB_TYPE(TRB_NORMAL) | TRB_IOC; + + if (cycle) + control &= cpu_to_le32(~TRB_CYCLE); + else + control |= cpu_to_le32(TRB_CYCLE); + + req->trb = ring->enqueue; + req->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue); + xhci_dbc_queue_trb(ring, + lower_32_bits(addr), + upper_32_bits(addr), + length, control); + + /* + * Add a barrier between writes of trb fields and flipping + * the cycle bit: + */ + wmb(); + + if (cycle) + trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE); + else + trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE); + + writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell); + + return 0; +} + +static int +dbc_ep_do_queue(struct dbc_request *req) +{ + int ret; + struct xhci_dbc *dbc = req->dbc; + struct device *dev = dbc->dev; + struct dbc_ep *dep = &dbc->eps[req->direction]; + + if (!req->length || !req->buf) + return -EINVAL; + + req->actual = 0; + req->status = -EINPROGRESS; + + req->dma = dma_map_single(dev, + req->buf, + req->length, + dbc_ep_dma_direction(dep)); + if (dma_mapping_error(dev, req->dma)) { + dev_err(dbc->dev, "failed to map buffer\n"); + return -EFAULT; + } + + ret = xhci_dbc_queue_bulk_tx(dep, req); + if (ret) { + dev_err(dbc->dev, "failed to queue trbs\n"); + dma_unmap_single(dev, + req->dma, + req->length, + dbc_ep_dma_direction(dep)); + return -EFAULT; + } + + list_add_tail(&req->list_pending, &dep->list_pending); + + return 0; +} + +int dbc_ep_queue(struct dbc_request *req) +{ + unsigned long flags; + struct xhci_dbc *dbc = req->dbc; + int ret = -ESHUTDOWN; + + if (!dbc) + return -ENODEV; + + if (req->direction != BULK_IN && + req->direction != BULK_OUT) + return -EINVAL; + + spin_lock_irqsave(&dbc->lock, flags); + if (dbc->state == DS_CONFIGURED) + ret = dbc_ep_do_queue(req); + spin_unlock_irqrestore(&dbc->lock, flags); + + mod_delayed_work(system_percpu_wq, &dbc->event_work, 0); + + trace_xhci_dbc_queue_request(req); + + return ret; +} + +static inline void xhci_dbc_do_eps_init(struct xhci_dbc *dbc, bool direction) +{ + struct dbc_ep *dep; + + dep = &dbc->eps[direction]; + dep->dbc = dbc; + dep->direction = direction; + dep->ring = direction ? dbc->ring_in : dbc->ring_out; + + INIT_LIST_HEAD(&dep->list_pending); +} + +static void xhci_dbc_eps_init(struct xhci_dbc *dbc) +{ + xhci_dbc_do_eps_init(dbc, BULK_OUT); + xhci_dbc_do_eps_init(dbc, BULK_IN); +} + +static void xhci_dbc_eps_exit(struct xhci_dbc *dbc) +{ + memset(dbc->eps, 0, sizeof_field(struct xhci_dbc, eps)); +} + +static int dbc_erst_alloc(struct device *dev, struct xhci_ring *evt_ring, + struct xhci_erst *erst, gfp_t flags) +{ + erst->entries = dma_alloc_coherent(dev, sizeof(*erst->entries), + &erst->erst_dma_addr, flags); + if (!erst->entries) + return -ENOMEM; + + erst->num_entries = 1; + erst->entries[0].seg_addr = cpu_to_le64(evt_ring->first_seg->dma); + erst->entries[0].seg_size = cpu_to_le32(TRBS_PER_SEGMENT); + erst->entries[0].rsvd = 0; + return 0; +} + +static void dbc_erst_free(struct device *dev, struct xhci_erst *erst) +{ + dma_free_coherent(dev, sizeof(*erst->entries), erst->entries, + erst->erst_dma_addr); + erst->entries = NULL; +} + +static struct xhci_container_ctx * +dbc_alloc_ctx(struct device *dev, gfp_t flags) +{ + struct xhci_container_ctx *ctx; + + ctx = kzalloc(sizeof(*ctx), flags); + if (!ctx) + return NULL; + + /* xhci 7.6.9, all three contexts; info, ep-out and ep-in. Each 64 bytes*/ + ctx->size = 3 * DBC_CONTEXT_SIZE; + ctx->bytes = dma_alloc_coherent(dev, ctx->size, &ctx->dma, flags); + if (!ctx->bytes) { + kfree(ctx); + return NULL; + } + return ctx; +} + +static void xhci_dbc_ring_init(struct xhci_ring *ring) +{ + struct xhci_segment *seg = ring->first_seg; + + /* clear all trbs on ring in case of old ring */ + memset(seg->trbs, 0, TRB_SEGMENT_SIZE); + + /* Only event ring does not use link TRB */ + if (ring->type != TYPE_EVENT) { + union xhci_trb *trb = &seg->trbs[TRBS_PER_SEGMENT - 1]; + + trb->link.segment_ptr = cpu_to_le64(ring->first_seg->dma); + trb->link.control = cpu_to_le32(LINK_TOGGLE | TRB_TYPE(TRB_LINK)); + } + xhci_initialize_ring_info(ring); +} + +static int xhci_dbc_reinit_ep_rings(struct xhci_dbc *dbc) +{ + struct xhci_ring *in_ring = dbc->eps[BULK_IN].ring; + struct xhci_ring *out_ring = dbc->eps[BULK_OUT].ring; + + if (!in_ring || !out_ring || !dbc->ctx) { + dev_warn(dbc->dev, "Can't re-init unallocated endpoints\n"); + return -ENODEV; + } + + xhci_dbc_ring_init(in_ring); + xhci_dbc_ring_init(out_ring); + + /* set ep context enqueue, dequeue, and cycle to initial values */ + xhci_dbc_init_ep_contexts(dbc); + + return 0; +} + +static struct xhci_ring * +xhci_dbc_ring_alloc(struct device *dev, enum xhci_ring_type type, gfp_t flags) +{ + struct xhci_ring *ring; + struct xhci_segment *seg; + dma_addr_t dma; + + ring = kzalloc(sizeof(*ring), flags); + if (!ring) + return NULL; + + ring->num_segs = 1; + ring->type = type; + + seg = kzalloc(sizeof(*seg), flags); + if (!seg) + goto seg_fail; + + ring->first_seg = seg; + ring->last_seg = seg; + seg->next = seg; + + seg->trbs = dma_alloc_coherent(dev, TRB_SEGMENT_SIZE, &dma, flags); + if (!seg->trbs) + goto dma_fail; + + seg->dma = dma; + + INIT_LIST_HEAD(&ring->td_list); + + xhci_dbc_ring_init(ring); + + return ring; +dma_fail: + kfree(seg); +seg_fail: + kfree(ring); + return NULL; +} + +static int xhci_dbc_mem_init(struct xhci_dbc *dbc, gfp_t flags) +{ + int ret; + dma_addr_t deq; + u32 string_length; + struct device *dev = dbc->dev; + + /* Allocate various rings for events and transfers: */ + dbc->ring_evt = xhci_dbc_ring_alloc(dev, TYPE_EVENT, flags); + if (!dbc->ring_evt) + goto evt_fail; + + dbc->ring_in = xhci_dbc_ring_alloc(dev, TYPE_BULK, flags); + if (!dbc->ring_in) + goto in_fail; + + dbc->ring_out = xhci_dbc_ring_alloc(dev, TYPE_BULK, flags); + if (!dbc->ring_out) + goto out_fail; + + /* Allocate and populate ERST: */ + ret = dbc_erst_alloc(dev, dbc->ring_evt, &dbc->erst, flags); + if (ret) + goto erst_fail; + + /* Allocate context data structure: */ + dbc->ctx = dbc_alloc_ctx(dev, flags); /* was sysdev, and is still */ + if (!dbc->ctx) + goto ctx_fail; + + /* Allocate the string table: */ + dbc->string_size = sizeof(*dbc->string); + dbc->string = dma_alloc_coherent(dev, dbc->string_size, + &dbc->string_dma, flags); + if (!dbc->string) + goto string_fail; + + /* Setup ERST register: */ + writel(dbc->erst.num_entries, &dbc->regs->ersts); + + lo_hi_writeq(dbc->erst.erst_dma_addr, &dbc->regs->erstba); + deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg, + dbc->ring_evt->dequeue); + lo_hi_writeq(deq, &dbc->regs->erdp); + + /* Setup strings and contexts: */ + string_length = xhci_dbc_populate_strings(dbc->string); + xhci_dbc_init_contexts(dbc, string_length); + + xhci_dbc_eps_init(dbc); + dbc->state = DS_INITIALIZED; + + return 0; + +string_fail: + dbc_free_ctx(dev, dbc->ctx); + dbc->ctx = NULL; +ctx_fail: + dbc_erst_free(dev, &dbc->erst); +erst_fail: + dbc_ring_free(dev, dbc->ring_out); + dbc->ring_out = NULL; +out_fail: + dbc_ring_free(dev, dbc->ring_in); + dbc->ring_in = NULL; +in_fail: + dbc_ring_free(dev, dbc->ring_evt); + dbc->ring_evt = NULL; +evt_fail: + return -ENOMEM; +} + +static void xhci_dbc_mem_cleanup(struct xhci_dbc *dbc) +{ + if (!dbc) + return; + + xhci_dbc_eps_exit(dbc); + + dma_free_coherent(dbc->dev, dbc->string_size, dbc->string, dbc->string_dma); + dbc->string = NULL; + + dbc_free_ctx(dbc->dev, dbc->ctx); + dbc->ctx = NULL; + + dbc_erst_free(dbc->dev, &dbc->erst); + dbc_ring_free(dbc->dev, dbc->ring_out); + dbc_ring_free(dbc->dev, dbc->ring_in); + dbc_ring_free(dbc->dev, dbc->ring_evt); + dbc->ring_in = NULL; + dbc->ring_out = NULL; + dbc->ring_evt = NULL; +} + +static int xhci_do_dbc_start(struct xhci_dbc *dbc) +{ + int ret; + u32 ctrl; + + if (dbc->state != DS_DISABLED) + return -EINVAL; + + writel(0, &dbc->regs->control); + ret = xhci_handshake(&dbc->regs->control, + DBC_CTRL_DBC_ENABLE, + 0, 1000); + if (ret) + return ret; + + ret = xhci_dbc_mem_init(dbc, GFP_ATOMIC); + if (ret) + return ret; + + ctrl = readl(&dbc->regs->control); + writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE, + &dbc->regs->control); + ret = xhci_handshake(&dbc->regs->control, + DBC_CTRL_DBC_ENABLE, + DBC_CTRL_DBC_ENABLE, 1000); + if (ret) + return ret; + + dbc->state = DS_ENABLED; + + return 0; +} + +static int xhci_do_dbc_stop(struct xhci_dbc *dbc) +{ + if (dbc->state == DS_DISABLED) + return -EINVAL; + + writel(0, &dbc->regs->control); + dbc->state = DS_DISABLED; + + return 0; +} + +static int xhci_dbc_start(struct xhci_dbc *dbc) +{ + int ret; + unsigned long flags; + + WARN_ON(!dbc); + + pm_runtime_get_sync(dbc->dev); /* note this was self.controller */ + + spin_lock_irqsave(&dbc->lock, flags); + ret = xhci_do_dbc_start(dbc); + spin_unlock_irqrestore(&dbc->lock, flags); + + if (ret) { + pm_runtime_put(dbc->dev); /* note this was self.controller */ + return ret; + } + + return mod_delayed_work(system_percpu_wq, &dbc->event_work, + msecs_to_jiffies(dbc->poll_interval)); +} + +static void xhci_dbc_stop(struct xhci_dbc *dbc) +{ + int ret; + unsigned long flags; + + WARN_ON(!dbc); + + switch (dbc->state) { + case DS_DISABLED: + return; + case DS_CONFIGURED: + spin_lock(&dbc->lock); + xhci_dbc_flush_requests(dbc); + spin_unlock(&dbc->lock); + + if (dbc->driver->disconnect) + dbc->driver->disconnect(dbc); + break; + default: + break; + } + + cancel_delayed_work_sync(&dbc->event_work); + + spin_lock_irqsave(&dbc->lock, flags); + ret = xhci_do_dbc_stop(dbc); + spin_unlock_irqrestore(&dbc->lock, flags); + if (ret) + return; + + xhci_dbc_mem_cleanup(dbc); + pm_runtime_put_sync(dbc->dev); /* note, was self.controller */ +} + +static void +handle_ep_halt_changes(struct xhci_dbc *dbc, struct dbc_ep *dep, bool halted) +{ + if (halted) { + dev_info(dbc->dev, "DbC Endpoint halted\n"); + dep->halted = 1; + + } else if (dep->halted) { + dev_info(dbc->dev, "DbC Endpoint halt cleared\n"); + dep->halted = 0; + + if (!list_empty(&dep->list_pending)) + writel(DBC_DOOR_BELL_TARGET(dep->direction), + &dbc->regs->doorbell); + } +} + +static void +dbc_handle_port_status(struct xhci_dbc *dbc, union xhci_trb *event) +{ + u32 portsc; + + portsc = readl(&dbc->regs->portsc); + if (portsc & DBC_PORTSC_CONN_CHANGE) + dev_info(dbc->dev, "DbC port connect change\n"); + + if (portsc & DBC_PORTSC_RESET_CHANGE) + dev_info(dbc->dev, "DbC port reset change\n"); + + if (portsc & DBC_PORTSC_LINK_CHANGE) + dev_info(dbc->dev, "DbC port link status change\n"); + + if (portsc & DBC_PORTSC_CONFIG_CHANGE) + dev_info(dbc->dev, "DbC config error change\n"); + + /* Port reset change bit will be cleared in other place: */ + writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc); +} + +static void dbc_handle_xfer_event(struct xhci_dbc *dbc, union xhci_trb *event) +{ + struct dbc_ep *dep; + struct xhci_ring *ring; + int ep_id; + int status; + struct xhci_ep_ctx *ep_ctx; + u32 comp_code; + size_t remain_length; + struct dbc_request *req = NULL, *r; + + comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2])); + remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2])); + ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3])); + dep = (ep_id == EPID_OUT) ? + get_out_ep(dbc) : get_in_ep(dbc); + ep_ctx = (ep_id == EPID_OUT) ? + dbc_bulkout_ctx(dbc) : dbc_bulkin_ctx(dbc); + ring = dep->ring; + + /* Match the pending request: */ + list_for_each_entry(r, &dep->list_pending, list_pending) { + if (r->trb_dma == event->trans_event.buffer) { + req = r; + break; + } + if (r->status == -COMP_STALL_ERROR) { + dev_warn(dbc->dev, "Give back stale stalled req\n"); + ring->num_trbs_free++; + xhci_dbc_giveback(r, 0); + } + } + + if (!req) { + dev_warn(dbc->dev, "no matched request\n"); + return; + } + + trace_xhci_dbc_handle_transfer(ring, &req->trb->generic, req->trb_dma); + + switch (comp_code) { + case COMP_SUCCESS: + remain_length = 0; + fallthrough; + case COMP_SHORT_PACKET: + status = 0; + break; + case COMP_TRB_ERROR: + case COMP_BABBLE_DETECTED_ERROR: + case COMP_USB_TRANSACTION_ERROR: + dev_warn(dbc->dev, "tx error %d detected\n", comp_code); + status = -comp_code; + break; + case COMP_STALL_ERROR: + dev_warn(dbc->dev, "Stall error at bulk TRB %llx, remaining %zu, ep deq %llx\n", + event->trans_event.buffer, remain_length, ep_ctx->deq); + status = 0; + dep->halted = 1; + + /* + * xHC DbC may trigger a STALL bulk xfer event when host sends a + * ClearFeature(ENDPOINT_HALT) request even if there wasn't an + * active bulk transfer. + * + * Don't give back this transfer request as hardware will later + * start processing TRBs starting from this 'STALLED' TRB, + * causing TRBs and requests to be out of sync. + * + * If STALL event shows some bytes were transferred then assume + * it's an actual transfer issue and give back the request. + * In this case mark the TRB as No-Op to avoid hw from using the + * TRB again. + */ + + if ((ep_ctx->deq & ~TRB_CYCLE) == event->trans_event.buffer) { + dev_dbg(dbc->dev, "Ep stopped on Stalled TRB\n"); + if (remain_length == req->length) { + dev_dbg(dbc->dev, "Spurious stall event, keep req\n"); + req->status = -COMP_STALL_ERROR; + req->actual = 0; + return; + } + dev_dbg(dbc->dev, "Give back stalled req, but turn TRB to No-op\n"); + trb_to_noop(req->trb); + } + break; + + default: + dev_err(dbc->dev, "unknown tx error %d\n", comp_code); + status = -comp_code; + break; + } + + ring->num_trbs_free++; + req->actual = req->length - remain_length; + xhci_dbc_giveback(req, status); +} + +static void inc_evt_deq(struct xhci_ring *ring) +{ + /* If on the last TRB of the segment go back to the beginning */ + if (ring->dequeue == &ring->deq_seg->trbs[TRBS_PER_SEGMENT - 1]) { + ring->cycle_state ^= 1; + ring->dequeue = ring->deq_seg->trbs; + return; + } + ring->dequeue++; +} + +static enum evtreturn xhci_dbc_do_handle_events(struct xhci_dbc *dbc) +{ + dma_addr_t deq; + union xhci_trb *evt; + enum evtreturn ret = EVT_DONE; + u32 ctrl, portsc; + bool update_erdp = false; + + /* DbC state machine: */ + switch (dbc->state) { + case DS_DISABLED: + case DS_INITIALIZED: + + return EVT_ERR; + case DS_ENABLED: + portsc = readl(&dbc->regs->portsc); + if (portsc & DBC_PORTSC_CONN_STATUS) { + dbc->state = DS_CONNECTED; + dev_info(dbc->dev, "DbC connected\n"); + } + + return EVT_DONE; + case DS_CONNECTED: + ctrl = readl(&dbc->regs->control); + if (ctrl & DBC_CTRL_DBC_RUN) { + dbc->state = DS_CONFIGURED; + dev_info(dbc->dev, "DbC configured\n"); + portsc = readl(&dbc->regs->portsc); + writel(portsc, &dbc->regs->portsc); + ret = EVT_GSER; + break; + } + + return EVT_DONE; + case DS_CONFIGURED: + /* Handle cable unplug event: */ + portsc = readl(&dbc->regs->portsc); + if (!(portsc & DBC_PORTSC_PORT_ENABLED) && + !(portsc & DBC_PORTSC_CONN_STATUS)) { + dev_info(dbc->dev, "DbC cable unplugged\n"); + dbc->state = DS_ENABLED; + xhci_dbc_flush_requests(dbc); + xhci_dbc_reinit_ep_rings(dbc); + return EVT_DISC; + } + + /* Handle debug port reset event: */ + if (portsc & DBC_PORTSC_RESET_CHANGE) { + dev_info(dbc->dev, "DbC port reset\n"); + writel(portsc, &dbc->regs->portsc); + dbc->state = DS_ENABLED; + xhci_dbc_flush_requests(dbc); + xhci_dbc_reinit_ep_rings(dbc); + return EVT_DISC; + } + + /* Check and handle changes in endpoint halt status */ + ctrl = readl(&dbc->regs->control); + handle_ep_halt_changes(dbc, get_in_ep(dbc), ctrl & DBC_CTRL_HALT_IN_TR); + handle_ep_halt_changes(dbc, get_out_ep(dbc), ctrl & DBC_CTRL_HALT_OUT_TR); + + /* Clear DbC run change bit: */ + if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) { + writel(ctrl, &dbc->regs->control); + ctrl = readl(&dbc->regs->control); + } + break; + default: + dev_err(dbc->dev, "Unknown DbC state %d\n", dbc->state); + break; + } + + /* Handle the events in the event ring: */ + evt = dbc->ring_evt->dequeue; + while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) == + dbc->ring_evt->cycle_state) { + /* + * Add a barrier between reading the cycle flag and any + * reads of the event's flags/data below: + */ + rmb(); + + trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic, + xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg, + dbc->ring_evt->dequeue)); + + switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) { + case TRB_TYPE(TRB_PORT_STATUS): + dbc_handle_port_status(dbc, evt); + break; + case TRB_TYPE(TRB_TRANSFER): + dbc_handle_xfer_event(dbc, evt); + if (ret != EVT_GSER) + ret = EVT_XFER_DONE; + break; + default: + break; + } + + inc_evt_deq(dbc->ring_evt); + + evt = dbc->ring_evt->dequeue; + update_erdp = true; + } + + /* Update event ring dequeue pointer: */ + if (update_erdp) { + deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg, + dbc->ring_evt->dequeue); + lo_hi_writeq(deq, &dbc->regs->erdp); + } + + return ret; +} + +static void xhci_dbc_handle_events(struct work_struct *work) +{ + enum evtreturn evtr; + struct xhci_dbc *dbc; + unsigned long flags; + unsigned int poll_interval; + unsigned long busypoll_timelimit; + + dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work); + poll_interval = dbc->poll_interval; + + spin_lock_irqsave(&dbc->lock, flags); + evtr = xhci_dbc_do_handle_events(dbc); + spin_unlock_irqrestore(&dbc->lock, flags); + + switch (evtr) { + case EVT_GSER: + if (dbc->driver->configure) + dbc->driver->configure(dbc); + break; + case EVT_DISC: + if (dbc->driver->disconnect) + dbc->driver->disconnect(dbc); + break; + case EVT_DONE: + /* + * Set fast poll rate if there are pending out transfers, or + * a transfer was recently processed + */ + busypoll_timelimit = dbc->xfer_timestamp + + msecs_to_jiffies(DBC_XFER_INACTIVITY_TIMEOUT); + + if (!list_empty(&dbc->eps[BULK_OUT].list_pending) || + time_is_after_jiffies(busypoll_timelimit)) + poll_interval = 0; + break; + case EVT_XFER_DONE: + dbc->xfer_timestamp = jiffies; + poll_interval = 0; + break; + default: + dev_info(dbc->dev, "stop handling dbc events\n"); + return; + } + + mod_delayed_work(system_percpu_wq, &dbc->event_work, + msecs_to_jiffies(poll_interval)); +} + +static const char * const dbc_state_strings[DS_MAX] = { + [DS_DISABLED] = "disabled", + [DS_INITIALIZED] = "initialized", + [DS_ENABLED] = "enabled", + [DS_CONNECTED] = "connected", + [DS_CONFIGURED] = "configured", +}; + +static ssize_t dbc_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + if (dbc->state >= ARRAY_SIZE(dbc_state_strings)) + return sysfs_emit(buf, "unknown\n"); + + return sysfs_emit(buf, "%s\n", dbc_state_strings[dbc->state]); +} + +static ssize_t dbc_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct xhci_hcd *xhci; + struct xhci_dbc *dbc; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + if (sysfs_streq(buf, "enable")) + xhci_dbc_start(dbc); + else if (sysfs_streq(buf, "disable")) + xhci_dbc_stop(dbc); + else + return -EINVAL; + + return count; +} + +static ssize_t dbc_idVendor_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + return sysfs_emit(buf, "%04x\n", dbc->idVendor); +} + +static ssize_t dbc_idVendor_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + void __iomem *ptr; + u16 value; + u32 dev_info; + int ret; + + ret = kstrtou16(buf, 0, &value); + if (ret) + return ret; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + if (dbc->state != DS_DISABLED) + return -EBUSY; + + dbc->idVendor = value; + ptr = &dbc->regs->devinfo1; + dev_info = readl(ptr); + dev_info = (dev_info & ~(0xffffu << 16)) | (value << 16); + writel(dev_info, ptr); + + return size; +} + +static ssize_t dbc_idProduct_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + return sysfs_emit(buf, "%04x\n", dbc->idProduct); +} + +static ssize_t dbc_idProduct_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + void __iomem *ptr; + u32 dev_info; + u16 value; + int ret; + + ret = kstrtou16(buf, 0, &value); + if (ret) + return ret; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + if (dbc->state != DS_DISABLED) + return -EBUSY; + + dbc->idProduct = value; + ptr = &dbc->regs->devinfo2; + dev_info = readl(ptr); + dev_info = (dev_info & ~(0xffffu)) | value; + writel(dev_info, ptr); + return size; +} + +static ssize_t dbc_bcdDevice_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + return sysfs_emit(buf, "%04x\n", dbc->bcdDevice); +} + +static ssize_t dbc_bcdDevice_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + void __iomem *ptr; + u32 dev_info; + u16 value; + int ret; + + ret = kstrtou16(buf, 0, &value); + if (ret) + return ret; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + if (dbc->state != DS_DISABLED) + return -EBUSY; + + dbc->bcdDevice = value; + ptr = &dbc->regs->devinfo2; + dev_info = readl(ptr); + dev_info = (dev_info & ~(0xffffu << 16)) | (value << 16); + writel(dev_info, ptr); + + return size; +} + +static ssize_t dbc_bInterfaceProtocol_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + return sysfs_emit(buf, "%02x\n", dbc->bInterfaceProtocol); +} + +static ssize_t dbc_bInterfaceProtocol_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + void __iomem *ptr; + u32 dev_info; + u8 value; + int ret; + + /* bInterfaceProtocol is 8 bit, but... */ + ret = kstrtou8(buf, 0, &value); + if (ret) + return ret; + + /* ...xhci only supports values 0 and 1 */ + if (value > 1) + return -EINVAL; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + if (dbc->state != DS_DISABLED) + return -EBUSY; + + dbc->bInterfaceProtocol = value; + ptr = &dbc->regs->devinfo1; + dev_info = readl(ptr); + dev_info = (dev_info & ~(0xffu)) | value; + writel(dev_info, ptr); + + return size; +} + +static ssize_t dbc_poll_interval_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + return sysfs_emit(buf, "%u\n", dbc->poll_interval); +} + +static ssize_t dbc_poll_interval_ms_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xhci_dbc *dbc; + struct xhci_hcd *xhci; + u32 value; + int ret; + + ret = kstrtou32(buf, 0, &value); + if (ret || value > DBC_POLL_INTERVAL_MAX) + return -EINVAL; + + xhci = hcd_to_xhci(dev_get_drvdata(dev)); + dbc = xhci->dbc; + + dbc->poll_interval = value; + + mod_delayed_work(system_percpu_wq, &dbc->event_work, 0); + + return size; +} + +static DEVICE_ATTR_RW(dbc); +static DEVICE_ATTR_RW(dbc_idVendor); +static DEVICE_ATTR_RW(dbc_idProduct); +static DEVICE_ATTR_RW(dbc_bcdDevice); +static DEVICE_ATTR_RW(dbc_bInterfaceProtocol); +static DEVICE_ATTR_RW(dbc_poll_interval_ms); + +static struct attribute *dbc_dev_attrs[] = { + &dev_attr_dbc.attr, + &dev_attr_dbc_idVendor.attr, + &dev_attr_dbc_idProduct.attr, + &dev_attr_dbc_bcdDevice.attr, + &dev_attr_dbc_bInterfaceProtocol.attr, + &dev_attr_dbc_poll_interval_ms.attr, + NULL +}; +ATTRIBUTE_GROUPS(dbc_dev); + +struct xhci_dbc * +xhci_alloc_dbc(struct device *dev, void __iomem *base, const struct dbc_driver *driver) +{ + struct xhci_dbc *dbc; + int ret; + + dbc = kzalloc(sizeof(*dbc), GFP_KERNEL); + if (!dbc) + return NULL; + + dbc->regs = base; + dbc->dev = dev; + dbc->driver = driver; + dbc->idProduct = DBC_PRODUCT_ID; + dbc->idVendor = DBC_VENDOR_ID; + dbc->bcdDevice = DBC_DEVICE_REV; + dbc->bInterfaceProtocol = DBC_PROTOCOL; + dbc->poll_interval = DBC_POLL_INTERVAL_DEFAULT; + + if (readl(&dbc->regs->control) & DBC_CTRL_DBC_ENABLE) + goto err; + + INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events); + spin_lock_init(&dbc->lock); + + ret = sysfs_create_groups(&dev->kobj, dbc_dev_groups); + if (ret) + goto err; + + return dbc; +err: + kfree(dbc); + return NULL; +} + +/* undo what xhci_alloc_dbc() did */ +void xhci_dbc_remove(struct xhci_dbc *dbc) +{ + if (!dbc) + return; + /* stop hw, stop wq and call dbc->ops->stop() */ + xhci_dbc_stop(dbc); + + /* remove sysfs files */ + sysfs_remove_groups(&dbc->dev->kobj, dbc_dev_groups); + + kfree(dbc); +} + + +int xhci_create_dbc_dev(struct xhci_hcd *xhci) +{ + struct device *dev; + void __iomem *base; + int ret; + int dbc_cap_offs; + + /* create all parameters needed resembling a dbc device */ + dev = xhci_to_hcd(xhci)->self.controller; + base = &xhci->cap_regs->hc_capbase; + + dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG); + if (!dbc_cap_offs) + return -ENODEV; + + /* already allocated and in use */ + if (xhci->dbc) + return -EBUSY; + + ret = xhci_dbc_tty_probe(dev, base + dbc_cap_offs, xhci); + + return ret; +} + +void xhci_remove_dbc_dev(struct xhci_hcd *xhci) +{ + unsigned long flags; + + if (!xhci->dbc) + return; + + xhci_dbc_tty_remove(xhci->dbc); + spin_lock_irqsave(&xhci->lock, flags); + xhci->dbc = NULL; + spin_unlock_irqrestore(&xhci->lock, flags); +} + +#ifdef CONFIG_PM +int xhci_dbc_suspend(struct xhci_hcd *xhci) +{ + struct xhci_dbc *dbc = xhci->dbc; + + if (!dbc) + return 0; + + switch (dbc->state) { + case DS_ENABLED: + case DS_CONNECTED: + case DS_CONFIGURED: + dbc->resume_required = 1; + break; + default: + break; + } + + xhci_dbc_stop(dbc); + + return 0; +} + +int xhci_dbc_resume(struct xhci_hcd *xhci) +{ + int ret = 0; + struct xhci_dbc *dbc = xhci->dbc; + + if (!dbc) + return 0; + + if (dbc->resume_required) { + dbc->resume_required = 0; + xhci_dbc_start(dbc); + } + + return ret; +} +#endif /* CONFIG_PM */ + +int xhci_dbc_init(void) +{ + return dbc_tty_init(); +} + +void xhci_dbc_exit(void) +{ + dbc_tty_exit(); +} |