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path: root/drivers/usb/cdns3/gadget.c
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Diffstat (limited to 'drivers/usb/cdns3/gadget.c')
-rw-r--r--drivers/usb/cdns3/gadget.c2645
1 files changed, 2645 insertions, 0 deletions
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
new file mode 100644
index 000000000000..63cde269db98
--- /dev/null
+++ b/drivers/usb/cdns3/gadget.c
@@ -0,0 +1,2645 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - gadget side.
+ *
+ * Copyright (C) 2018-2019 Cadence Design Systems.
+ * Copyright (C) 2017-2018 NXP
+ *
+ * Authors: Pawel Jez <pjez@cadence.com>,
+ * Pawel Laszczak <pawell@cadence.com>
+ * Peter Chen <peter.chen@nxp.com>
+ */
+
+/*
+ * Work around 1:
+ * At some situations, the controller may get stale data address in TRB
+ * at below sequences:
+ * 1. Controller read TRB includes data address
+ * 2. Software updates TRBs includes data address and Cycle bit
+ * 3. Controller read TRB which includes Cycle bit
+ * 4. DMA run with stale data address
+ *
+ * To fix this problem, driver needs to make the first TRB in TD as invalid.
+ * After preparing all TRBs driver needs to check the position of DMA and
+ * if the DMA point to the first just added TRB and doorbell is 1,
+ * then driver must defer making this TRB as valid. This TRB will be make
+ * as valid during adding next TRB only if DMA is stopped or at TRBERR
+ * interrupt.
+ *
+ * Issue has been fixed in DEV_VER_V3 version of controller.
+ *
+ * Work around 2:
+ * Controller for OUT endpoints has shared on-chip buffers for all incoming
+ * packets, including ep0out. It's FIFO buffer, so packets must be handle by DMA
+ * in correct order. If the first packet in the buffer will not be handled,
+ * then the following packets directed for other endpoints and functions
+ * will be blocked.
+ * Additionally the packets directed to one endpoint can block entire on-chip
+ * buffers. In this case transfer to other endpoints also will blocked.
+ *
+ * To resolve this issue after raising the descriptor missing interrupt
+ * driver prepares internal usb_request object and use it to arm DMA transfer.
+ *
+ * The problematic situation was observed in case when endpoint has been enabled
+ * but no usb_request were queued. Driver try detects such endpoints and will
+ * use this workaround only for these endpoint.
+ *
+ * Driver use limited number of buffer. This number can be set by macro
+ * CDNS3_WA2_NUM_BUFFERS.
+ *
+ * Such blocking situation was observed on ACM gadget. For this function
+ * host send OUT data packet but ACM function is not prepared for this packet.
+ * It's cause that buffer placed in on chip memory block transfer to other
+ * endpoints.
+ *
+ * Issue has been fixed in DEV_VER_V2 version of controller.
+ *
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/usb/gadget.h>
+#include <linux/module.h>
+
+#include "core.h"
+#include "gadget-export.h"
+#include "gadget.h"
+#include "trace.h"
+#include "drd.h"
+
+static int __cdns3_gadget_ep_queue(struct usb_ep *ep,
+ struct usb_request *request,
+ gfp_t gfp_flags);
+
+/**
+ * cdns3_set_register_bit - set bit in given register.
+ * @ptr: address of device controller register to be read and changed
+ * @mask: bits requested to set
+ */
+void cdns3_set_register_bit(void __iomem *ptr, u32 mask)
+{
+ mask = readl(ptr) | mask;
+ writel(mask, ptr);
+}
+
+/**
+ * cdns3_ep_addr_to_index - Macro converts endpoint address to
+ * index of endpoint object in cdns3_device.eps[] container
+ * @ep_addr: endpoint address for which endpoint object is required
+ *
+ */
+u8 cdns3_ep_addr_to_index(u8 ep_addr)
+{
+ return (((ep_addr & 0x7F)) + ((ep_addr & USB_DIR_IN) ? 16 : 0));
+}
+
+static int cdns3_get_dma_pos(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep)
+{
+ int dma_index;
+
+ dma_index = readl(&priv_dev->regs->ep_traddr) - priv_ep->trb_pool_dma;
+
+ return dma_index / TRB_SIZE;
+}
+
+/**
+ * cdns3_next_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct usb_request *cdns3_next_request(struct list_head *list)
+{
+ return list_first_entry_or_null(list, struct usb_request, list);
+}
+
+/**
+ * cdns3_next_align_buf - returns next buffer from list
+ * @list: list containing buffers
+ *
+ * Returns buffer or NULL if no buffers in list
+ */
+struct cdns3_aligned_buf *cdns3_next_align_buf(struct list_head *list)
+{
+ return list_first_entry_or_null(list, struct cdns3_aligned_buf, list);
+}
+
+/**
+ * cdns3_next_priv_request - returns next request from list
+ * @list: list containing requests
+ *
+ * Returns request or NULL if no requests in list
+ */
+struct cdns3_request *cdns3_next_priv_request(struct list_head *list)
+{
+ return list_first_entry_or_null(list, struct cdns3_request, list);
+}
+
+/**
+ * select_ep - selects endpoint
+ * @priv_dev: extended gadget object
+ * @ep: endpoint address
+ */
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep)
+{
+ if (priv_dev->selected_ep == ep)
+ return;
+
+ priv_dev->selected_ep = ep;
+ writel(ep, &priv_dev->regs->ep_sel);
+}
+
+dma_addr_t cdns3_trb_virt_to_dma(struct cdns3_endpoint *priv_ep,
+ struct cdns3_trb *trb)
+{
+ u32 offset = (char *)trb - (char *)priv_ep->trb_pool;
+
+ return priv_ep->trb_pool_dma + offset;
+}
+
+int cdns3_ring_size(struct cdns3_endpoint *priv_ep)
+{
+ switch (priv_ep->type) {
+ case USB_ENDPOINT_XFER_ISOC:
+ return TRB_ISO_RING_SIZE;
+ case USB_ENDPOINT_XFER_CONTROL:
+ return TRB_CTRL_RING_SIZE;
+ default:
+ return TRB_RING_SIZE;
+ }
+}
+
+/**
+ * cdns3_allocate_trb_pool - Allocates TRB's pool for selected endpoint
+ * @priv_ep: endpoint object
+ *
+ * Function will return 0 on success or -ENOMEM on allocation error
+ */
+int cdns3_allocate_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ int ring_size = cdns3_ring_size(priv_ep);
+ struct cdns3_trb *link_trb;
+
+ if (!priv_ep->trb_pool) {
+ priv_ep->trb_pool = dma_alloc_coherent(priv_dev->sysdev,
+ ring_size,
+ &priv_ep->trb_pool_dma,
+ GFP_DMA32 | GFP_ATOMIC);
+ if (!priv_ep->trb_pool)
+ return -ENOMEM;
+ } else {
+ memset(priv_ep->trb_pool, 0, ring_size);
+ }
+
+ if (!priv_ep->num)
+ return 0;
+
+ priv_ep->num_trbs = ring_size / TRB_SIZE;
+ /* Initialize the last TRB as Link TRB */
+ link_trb = (priv_ep->trb_pool + (priv_ep->num_trbs - 1));
+ link_trb->buffer = TRB_BUFFER(priv_ep->trb_pool_dma);
+ link_trb->control = TRB_CYCLE | TRB_TYPE(TRB_LINK) | TRB_TOGGLE;
+
+ return 0;
+}
+
+static void cdns3_free_trb_pool(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+ if (priv_ep->trb_pool) {
+ dma_free_coherent(priv_dev->sysdev,
+ cdns3_ring_size(priv_ep),
+ priv_ep->trb_pool, priv_ep->trb_pool_dma);
+ priv_ep->trb_pool = NULL;
+ }
+}
+
+/**
+ * cdns3_ep_stall_flush - Stalls and flushes selected endpoint
+ * @priv_ep: endpoint object
+ *
+ * Endpoint must be selected before call to this function
+ */
+static void cdns3_ep_stall_flush(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+ cdns3_dbg(priv_ep->cdns3_dev, "Stall & flush endpoint %s\n",
+ priv_ep->name);
+
+ writel(EP_CMD_DFLUSH | EP_CMD_ERDY | EP_CMD_SSTALL,
+ &priv_dev->regs->ep_cmd);
+
+ /* wait for DFLUSH cleared */
+ cdns3_handshake(&priv_dev->regs->ep_cmd, EP_CMD_DFLUSH, 0, 1000);
+ priv_ep->flags |= EP_STALL;
+}
+
+/**
+ * cdns3_hw_reset_eps_config - reset endpoints configuration kept by controller.
+ * @priv_dev: extended gadget object
+ */
+void cdns3_hw_reset_eps_config(struct cdns3_device *priv_dev)
+{
+ writel(USB_CONF_CFGRST, &priv_dev->regs->usb_conf);
+
+ cdns3_allow_enable_l1(priv_dev, 0);
+ priv_dev->hw_configured_flag = 0;
+ priv_dev->onchip_used_size = 0;
+ priv_dev->out_mem_is_allocated = 0;
+ priv_dev->wait_for_setup = 0;
+}
+
+/**
+ * cdns3_ep_inc_trb - increment a trb index.
+ * @index: Pointer to the TRB index to increment.
+ * @cs: Cycle state
+ * @trb_in_seg: number of TRBs in segment
+ *
+ * The index should never point to the link TRB. After incrementing,
+ * if it is point to the link TRB, wrap around to the beginning and revert
+ * cycle state bit The
+ * link TRB is always at the last TRB entry.
+ */
+static void cdns3_ep_inc_trb(int *index, u8 *cs, int trb_in_seg)
+{
+ (*index)++;
+ if (*index == (trb_in_seg - 1)) {
+ *index = 0;
+ *cs ^= 1;
+ }
+}
+
+/**
+ * cdns3_ep_inc_enq - increment endpoint's enqueue pointer
+ * @priv_ep: The endpoint whose enqueue pointer we're incrementing
+ */
+static void cdns3_ep_inc_enq(struct cdns3_endpoint *priv_ep)
+{
+ priv_ep->free_trbs--;
+ cdns3_ep_inc_trb(&priv_ep->enqueue, &priv_ep->pcs, priv_ep->num_trbs);
+}
+
+/**
+ * cdns3_ep_inc_deq - increment endpoint's dequeue pointer
+ * @priv_ep: The endpoint whose dequeue pointer we're incrementing
+ */
+static void cdns3_ep_inc_deq(struct cdns3_endpoint *priv_ep)
+{
+ priv_ep->free_trbs++;
+ cdns3_ep_inc_trb(&priv_ep->dequeue, &priv_ep->ccs, priv_ep->num_trbs);
+}
+
+void cdns3_move_deq_to_next_trb(struct cdns3_request *priv_req)
+{
+ struct cdns3_endpoint *priv_ep = priv_req->priv_ep;
+ int current_trb = priv_req->start_trb;
+
+ while (current_trb != priv_req->end_trb) {
+ cdns3_ep_inc_deq(priv_ep);
+ current_trb = priv_ep->dequeue;
+ }
+
+ cdns3_ep_inc_deq(priv_ep);
+}
+
+/**
+ * cdns3_allow_enable_l1 - enable/disable permits to transition to L1.
+ * @priv_dev: Extended gadget object
+ * @enable: Enable/disable permit to transition to L1.
+ *
+ * If bit USB_CONF_L1EN is set and device receive Extended Token packet,
+ * then controller answer with ACK handshake.
+ * If bit USB_CONF_L1DS is set and device receive Extended Token packet,
+ * then controller answer with NYET handshake.
+ */
+void cdns3_allow_enable_l1(struct cdns3_device *priv_dev, int enable)
+{
+ if (enable)
+ writel(USB_CONF_L1EN, &priv_dev->regs->usb_conf);
+ else
+ writel(USB_CONF_L1DS, &priv_dev->regs->usb_conf);
+}
+
+enum usb_device_speed cdns3_get_speed(struct cdns3_device *priv_dev)
+{
+ u32 reg;
+
+ reg = readl(&priv_dev->regs->usb_sts);
+
+ if (DEV_SUPERSPEED(reg))
+ return USB_SPEED_SUPER;
+ else if (DEV_HIGHSPEED(reg))
+ return USB_SPEED_HIGH;
+ else if (DEV_FULLSPEED(reg))
+ return USB_SPEED_FULL;
+ else if (DEV_LOWSPEED(reg))
+ return USB_SPEED_LOW;
+ return USB_SPEED_UNKNOWN;
+}
+
+/**
+ * cdns3_start_all_request - add to ring all request not started
+ * @priv_dev: Extended gadget object
+ * @priv_ep: The endpoint for whom request will be started.
+ *
+ * Returns return ENOMEM if transfer ring i not enough TRBs to start
+ * all requests.
+ */
+static int cdns3_start_all_request(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+ struct usb_request *request;
+ int ret = 0;
+
+ while (!list_empty(&priv_ep->deferred_req_list)) {
+ request = cdns3_next_request(&priv_ep->deferred_req_list);
+ priv_req = to_cdns3_request(request);
+
+ ret = cdns3_ep_run_transfer(priv_ep, request);
+ if (ret)
+ return ret;
+
+ list_del(&request->list);
+ list_add_tail(&request->list,
+ &priv_ep->pending_req_list);
+ }
+
+ priv_ep->flags &= ~EP_RING_FULL;
+ return ret;
+}
+
+/*
+ * WA2: Set flag for all not ISOC OUT endpoints. If this flag is set
+ * driver try to detect whether endpoint need additional internal
+ * buffer for unblocking on-chip FIFO buffer. This flag will be cleared
+ * if before first DESCMISS interrupt the DMA will be armed.
+ */
+#define cdns3_wa2_enable_detection(priv_dev, ep_priv, reg) do { \
+ if (!priv_ep->dir && priv_ep->type != USB_ENDPOINT_XFER_ISOC) { \
+ priv_ep->flags |= EP_QUIRK_EXTRA_BUF_DET; \
+ (reg) |= EP_STS_EN_DESCMISEN; \
+ } } while (0)
+
+/**
+ * cdns3_wa2_descmiss_copy_data copy data from internal requests to
+ * request queued by class driver.
+ * @priv_ep: extended endpoint object
+ * @request: request object
+ */
+static void cdns3_wa2_descmiss_copy_data(struct cdns3_endpoint *priv_ep,
+ struct usb_request *request)
+{
+ struct usb_request *descmiss_req;
+ struct cdns3_request *descmiss_priv_req;
+
+ while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+ int chunk_end;
+ int length;
+
+ descmiss_priv_req =
+ cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+ descmiss_req = &descmiss_priv_req->request;
+
+ /* driver can't touch pending request */
+ if (descmiss_priv_req->flags & REQUEST_PENDING)
+ break;
+
+ chunk_end = descmiss_priv_req->flags & REQUEST_INTERNAL_CH;
+ length = request->actual + descmiss_req->actual;
+
+ request->status = descmiss_req->status;
+
+ if (length <= request->length) {
+ memcpy(&((u8 *)request->buf)[request->actual],
+ descmiss_req->buf,
+ descmiss_req->actual);
+ request->actual = length;
+ } else {
+ /* It should never occures */
+ request->status = -ENOMEM;
+ }
+
+ list_del_init(&descmiss_priv_req->list);
+
+ kfree(descmiss_req->buf);
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint, descmiss_req);
+ --priv_ep->wa2_counter;
+
+ if (!chunk_end)
+ break;
+ }
+}
+
+struct usb_request *cdns3_wa2_gadget_giveback(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req)
+{
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN &&
+ priv_req->flags & REQUEST_INTERNAL) {
+ struct usb_request *req;
+
+ req = cdns3_next_request(&priv_ep->deferred_req_list);
+
+ priv_ep->descmis_req = NULL;
+
+ if (!req)
+ return NULL;
+
+ cdns3_wa2_descmiss_copy_data(priv_ep, req);
+ if (!(priv_ep->flags & EP_QUIRK_END_TRANSFER) &&
+ req->length != req->actual) {
+ /* wait for next part of transfer */
+ return NULL;
+ }
+
+ if (req->status == -EINPROGRESS)
+ req->status = 0;
+
+ list_del_init(&req->list);
+ cdns3_start_all_request(priv_dev, priv_ep);
+ return req;
+ }
+
+ return &priv_req->request;
+}
+
+int cdns3_wa2_gadget_ep_queue(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req)
+{
+ int deferred = 0;
+
+ /*
+ * If transfer was queued before DESCMISS appear than we
+ * can disable handling of DESCMISS interrupt. Driver assumes that it
+ * can disable special treatment for this endpoint.
+ */
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+ u32 reg;
+
+ cdns3_select_ep(priv_dev, priv_ep->num | priv_ep->dir);
+ priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+ reg = readl(&priv_dev->regs->ep_sts_en);
+ reg &= ~EP_STS_EN_DESCMISEN;
+ writel(reg, &priv_dev->regs->ep_sts_en);
+ }
+
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_EN) {
+ u8 pending_empty = list_empty(&priv_ep->pending_req_list);
+ u8 descmiss_empty = list_empty(&priv_ep->wa2_descmiss_req_list);
+
+ /*
+ * DESCMISS transfer has been finished, so data will be
+ * directly copied from internal allocated usb_request
+ * objects.
+ */
+ if (pending_empty && !descmiss_empty &&
+ !(priv_req->flags & REQUEST_INTERNAL)) {
+ cdns3_wa2_descmiss_copy_data(priv_ep,
+ &priv_req->request);
+ list_add_tail(&priv_req->request.list,
+ &priv_ep->pending_req_list);
+ cdns3_gadget_giveback(priv_ep, priv_req,
+ priv_req->request.status);
+
+ /*
+ * Intentionally driver returns positive value as
+ * correct value. It informs that transfer has
+ * been finished.
+ */
+ return EINPROGRESS;
+ }
+
+ /*
+ * Driver will wait for completion DESCMISS transfer,
+ * before starts new, not DESCMISS transfer.
+ */
+ if (!pending_empty && !descmiss_empty)
+ deferred = 1;
+
+ if (priv_req->flags & REQUEST_INTERNAL)
+ list_add_tail(&priv_req->list,
+ &priv_ep->wa2_descmiss_req_list);
+ }
+
+ return deferred;
+}
+
+static void cdsn3_wa2_remove_old_request(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+
+ while (!list_empty(&priv_ep->wa2_descmiss_req_list)) {
+ u8 chain;
+
+ priv_req = cdns3_next_priv_request(&priv_ep->wa2_descmiss_req_list);
+ chain = !!(priv_req->flags & REQUEST_INTERNAL_CH);
+
+ kfree(priv_req->request.buf);
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint,
+ &priv_req->request);
+ list_del_init(&priv_req->list);
+ --priv_ep->wa2_counter;
+
+ if (!chain)
+ break;
+ }
+}
+
+/**
+ * cdns3_wa2_descmissing_packet - handles descriptor missing event.
+ * @priv_dev: extended gadget object
+ *
+ * This function is used only for WA2. For more information see Work around 2
+ * description.
+ */
+static void cdns3_wa2_descmissing_packet(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+ struct usb_request *request;
+
+ if (priv_ep->flags & EP_QUIRK_EXTRA_BUF_DET) {
+ priv_ep->flags &= ~EP_QUIRK_EXTRA_BUF_DET;
+ priv_ep->flags |= EP_QUIRK_EXTRA_BUF_EN;
+ }
+
+ cdns3_dbg(priv_ep->cdns3_dev, "WA2: Description Missing detected\n");
+
+ if (priv_ep->wa2_counter >= CDNS3_WA2_NUM_BUFFERS)
+ cdsn3_wa2_remove_old_request(priv_ep);
+
+ request = cdns3_gadget_ep_alloc_request(&priv_ep->endpoint,
+ GFP_ATOMIC);
+ if (!request)
+ goto err;
+
+ priv_req = to_cdns3_request(request);
+ priv_req->flags |= REQUEST_INTERNAL;
+
+ /* if this field is still assigned it indicate that transfer related
+ * with this request has not been finished yet. Driver in this
+ * case simply allocate next request and assign flag REQUEST_INTERNAL_CH
+ * flag to previous one. It will indicate that current request is
+ * part of the previous one.
+ */
+ if (priv_ep->descmis_req)
+ priv_ep->descmis_req->flags |= REQUEST_INTERNAL_CH;
+
+ priv_req->request.buf = kzalloc(CDNS3_DESCMIS_BUF_SIZE,
+ GFP_ATOMIC);
+ priv_ep->wa2_counter++;
+
+ if (!priv_req->request.buf) {
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+ goto err;
+ }
+
+ priv_req->request.length = CDNS3_DESCMIS_BUF_SIZE;
+ priv_ep->descmis_req = priv_req;
+
+ __cdns3_gadget_ep_queue(&priv_ep->endpoint,
+ &priv_ep->descmis_req->request,
+ GFP_ATOMIC);
+
+ return;
+
+err:
+ dev_err(priv_ep->cdns3_dev->dev,
+ "Failed: No sufficient memory for DESCMIS\n");
+}
+
+/**
+ * cdns3_gadget_giveback - call struct usb_request's ->complete callback
+ * @priv_ep: The endpoint to whom the request belongs to
+ * @priv_req: The request we're giving back
+ * @status: completion code for the request
+ *
+ * Must be called with controller's lock held and interrupts disabled. This
+ * function will unmap @req and call its ->complete() callback to notify upper
+ * layers that it has completed.
+ */
+void cdns3_gadget_giveback(struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req,
+ int status)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ struct usb_request *request = &priv_req->request;
+
+ list_del_init(&request->list);
+
+ if (request->status == -EINPROGRESS)
+ request->status = status;
+
+ usb_gadget_unmap_request_by_dev(priv_dev->sysdev, request,
+ priv_ep->dir);
+
+ if ((priv_req->flags & REQUEST_UNALIGNED) &&
+ priv_ep->dir == USB_DIR_OUT && !request->status)
+ memcpy(request->buf, priv_req->aligned_buf->buf,
+ request->length);
+
+ priv_req->flags &= ~(REQUEST_PENDING | REQUEST_UNALIGNED);
+ trace_cdns3_gadget_giveback(priv_req);
+
+ if (priv_dev->dev_ver < DEV_VER_V2) {
+ request = cdns3_wa2_gadget_giveback(priv_dev, priv_ep,
+ priv_req);
+ if (!request)
+ return;
+ }
+
+ if (request->complete) {
+ spin_unlock(&priv_dev->lock);
+ usb_gadget_giveback_request(&priv_ep->endpoint,
+ request);
+ spin_lock(&priv_dev->lock);
+ }
+
+ if (request->buf == priv_dev->zlp_buf)
+ cdns3_gadget_ep_free_request(&priv_ep->endpoint, request);
+}
+
+void cdns3_wa1_restore_cycle_bit(struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+ /* Work around for stale data address in TRB*/
+ if (priv_ep->wa1_set) {
+ cdns3_dbg(priv_dev, "WA1: update cycle bit\n");
+ priv_ep->wa1_set = 0;
+ priv_ep->wa1_trb_index = 0xFFFF;
+ if (priv_ep->wa1_cycle_bit) {
+ priv_ep->wa1_trb->control =
+ priv_ep->wa1_trb->control | 0x1;
+ } else {
+ priv_ep->wa1_trb->control =
+ priv_ep->wa1_trb->control & ~0x1;
+ }
+ }
+}
+
+static int cdns3_prepare_aligned_request_buf(struct cdns3_request *priv_req)
+{
+ struct cdns3_endpoint *priv_ep = priv_req->priv_ep;
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ struct cdns3_aligned_buf *buf;
+
+ /* check if buffer is aligned to 8. */
+ if (!((uintptr_t)priv_req->request.buf & 0x7))
+ return 0;
+
+ buf = priv_req->aligned_buf;
+
+ if (!buf || priv_req->request.length > buf->size) {
+ buf = kzalloc(sizeof(*buf), GFP_ATOMIC);
+ if (!buf)
+ return -ENOMEM;
+
+ buf->size = priv_req->request.length;
+
+ buf->buf = dma_alloc_coherent(priv_dev->sysdev,
+ buf->size,
+ &buf->dma,
+ GFP_ATOMIC);
+ if (!buf->buf) {
+ kfree(buf);
+ return -ENOMEM;
+ }
+
+ if (priv_req->aligned_buf) {
+ trace_cdns3_free_aligned_request(priv_req);
+ priv_req->aligned_buf->in_use = 0;
+ priv_dev->run_garbage_colector = 1;
+ }
+
+ buf->in_use = 1;
+ priv_req->aligned_buf = buf;
+
+ list_add_tail(&buf->list,
+ &priv_dev->aligned_buf_list);
+ }
+
+ if (priv_ep->dir == USB_DIR_IN) {
+ memcpy(buf->buf, priv_req->request.buf,
+ priv_req->request.length);
+ }
+
+ priv_req->flags |= REQUEST_UNALIGNED;
+ trace_cdns3_prepare_aligned_request(priv_req);
+
+ return 0;
+}
+
+static int cdns3_wa1_update_guard(struct cdns3_endpoint *priv_ep,
+ struct cdns3_trb *trb)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+
+ if (!priv_ep->wa1_set) {
+ u32 doorbell;
+
+ doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+ if (doorbell) {
+ priv_ep->wa1_cycle_bit = priv_ep->pcs ? TRB_CYCLE : 0;
+ priv_ep->wa1_set = 1;
+ priv_ep->wa1_trb = trb;
+ priv_ep->wa1_trb_index = priv_ep->enqueue;
+ cdns3_dbg(priv_dev, "WA1 set guard\n");
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static void cdns3_wa1_tray_restore_cycle_bit(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep)
+{
+ int dma_index;
+ u32 doorbell;
+
+ doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+ dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+ if (!doorbell || dma_index != priv_ep->wa1_trb_index)
+ cdns3_wa1_restore_cycle_bit(priv_ep);
+}
+
+/**
+ * cdns3_ep_run_transfer - start transfer on no-default endpoint hardware
+ * @priv_ep: endpoint object
+ *
+ * Returns zero on success or negative value on failure
+ */
+int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
+ struct usb_request *request)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ struct cdns3_request *priv_req;
+ struct cdns3_trb *trb;
+ dma_addr_t trb_dma;
+ u32 togle_pcs = 1;
+ int sg_iter = 0;
+ int num_trb;
+ int address;
+ u32 control;
+ int pcs;
+
+ if (priv_ep->type == USB_ENDPOINT_XFER_ISOC)
+ num_trb = priv_ep->interval;
+ else
+ num_trb = request->num_sgs ? request->num_sgs : 1;
+
+ if (num_trb > priv_ep->free_trbs) {
+ priv_ep->flags |= EP_RING_FULL;
+ return -ENOBUFS;
+ }
+
+ priv_req = to_cdns3_request(request);
+ address = priv_ep->endpoint.desc->bEndpointAddress;
+
+ priv_ep->flags |= EP_PENDING_REQUEST;
+
+ /* must allocate buffer aligned to 8 */
+ if (priv_req->flags & REQUEST_UNALIGNED)
+ trb_dma = priv_req->aligned_buf->dma;
+ else
+ trb_dma = request->dma;
+
+ trb = priv_ep->trb_pool + priv_ep->enqueue;
+ priv_req->start_trb = priv_ep->enqueue;
+ priv_req->trb = trb;
+
+ cdns3_select_ep(priv_ep->cdns3_dev, address);
+
+ /* prepare ring */
+ if ((priv_ep->enqueue + num_trb) >= (priv_ep->num_trbs - 1)) {
+ struct cdns3_trb *link_trb;
+ int doorbell, dma_index;
+ u32 ch_bit = 0;
+
+ doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+ dma_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+
+ /* Driver can't update LINK TRB if it is current processed. */
+ if (doorbell && dma_index == priv_ep->num_trbs - 1) {
+ priv_ep->flags |= EP_DEFERRED_DRDY;
+ return -ENOBUFS;
+ }
+
+ /*updating C bt in Link TRB before starting DMA*/
+ link_trb = priv_ep->trb_pool + (priv_ep->num_trbs - 1);
+ /*
+ * For TRs size equal 2 enabling TRB_CHAIN for epXin causes
+ * that DMA stuck at the LINK TRB.
+ * On the other hand, removing TRB_CHAIN for longer TRs for
+ * epXout cause that DMA stuck after handling LINK TRB.
+ * To eliminate this strange behavioral driver set TRB_CHAIN
+ * bit only for TR size > 2.
+ */
+ if (priv_ep->type == USB_ENDPOINT_XFER_ISOC ||
+ TRBS_PER_SEGMENT > 2)
+ ch_bit = TRB_CHAIN;
+
+ link_trb->control = ((priv_ep->pcs) ? TRB_CYCLE : 0) |
+ TRB_TYPE(TRB_LINK) | TRB_TOGGLE | ch_bit;
+ }
+
+ if (priv_dev->dev_ver <= DEV_VER_V2)
+ togle_pcs = cdns3_wa1_update_guard(priv_ep, trb);
+
+ /* set incorrect Cycle Bit for first trb*/
+ control = priv_ep->pcs ? 0 : TRB_CYCLE;
+
+ do {
+ u32 length;
+ u16 td_size = 0;
+
+ /* fill TRB */
+ control |= TRB_TYPE(TRB_NORMAL);
+ trb->buffer = TRB_BUFFER(request->num_sgs == 0
+ ? trb_dma : request->sg[sg_iter].dma_address);
+
+ if (likely(!request->num_sgs))
+ length = request->length;
+ else
+ length = request->sg[sg_iter].length;
+
+ if (likely(priv_dev->dev_ver >= DEV_VER_V2))
+ td_size = DIV_ROUND_UP(length,
+ priv_ep->endpoint.maxpacket);
+
+ trb->length = TRB_BURST_LEN(priv_ep->trb_burst_size) |
+ TRB_LEN(length);
+ if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+ trb->length |= TRB_TDL_SS_SIZE(td_size);
+ else
+ control |= TRB_TDL_HS_SIZE(td_size);
+
+ pcs = priv_ep->pcs ? TRB_CYCLE : 0;
+
+ /*
+ * first trb should be prepared as last to avoid processing
+ * transfer to early
+ */
+ if (sg_iter != 0)
+ control |= pcs;
+
+ if (priv_ep->type == USB_ENDPOINT_XFER_ISOC && !priv_ep->dir) {
+ control |= TRB_IOC | TRB_ISP;
+ } else {
+ /* for last element in TD or in SG list */
+ if (sg_iter == (num_trb - 1) && sg_iter != 0)
+ control |= pcs | TRB_IOC | TRB_ISP;
+ }
+
+ if (sg_iter)
+ trb->control = control;
+ else
+ priv_req->trb->control = control;
+
+ control = 0;
+ ++sg_iter;
+ priv_req->end_trb = priv_ep->enqueue;
+ cdns3_ep_inc_enq(priv_ep);
+ trb = priv_ep->trb_pool + priv_ep->enqueue;
+ } while (sg_iter < num_trb);
+
+ trb = priv_req->trb;
+
+ priv_req->flags |= REQUEST_PENDING;
+
+ if (sg_iter == 1)
+ trb->control |= TRB_IOC | TRB_ISP;
+ /*
+ * Memory barrier - cycle bit must be set before other filds in trb.
+ */
+ wmb();
+
+ /* give the TD to the consumer*/
+ if (togle_pcs)
+ trb->control = trb->control ^ 1;
+
+ if (priv_dev->dev_ver <= DEV_VER_V2)
+ cdns3_wa1_tray_restore_cycle_bit(priv_dev, priv_ep);
+
+ trace_cdns3_prepare_trb(priv_ep, priv_req->trb);
+
+ /*
+ * Memory barrier - Cycle Bit must be set before trb->length and
+ * trb->buffer fields.
+ */
+ wmb();
+
+ /*
+ * For DMULT mode we can set address to transfer ring only once after
+ * enabling endpoint.
+ */
+ if (priv_ep->flags & EP_UPDATE_EP_TRBADDR) {
+ /*
+ * Until SW is not ready to handle the OUT transfer the ISO OUT
+ * Endpoint should be disabled (EP_CFG.ENABLE = 0).
+ * EP_CFG_ENABLE must be set before updating ep_traddr.
+ */
+ if (priv_ep->type == USB_ENDPOINT_XFER_ISOC && !priv_ep->dir &&
+ !(priv_ep->flags & EP_QUIRK_ISO_OUT_EN)) {
+ priv_ep->flags |= EP_QUIRK_ISO_OUT_EN;
+ cdns3_set_register_bit(&priv_dev->regs->ep_cfg,
+ EP_CFG_ENABLE);
+ }
+
+ writel(EP_TRADDR_TRADDR(priv_ep->trb_pool_dma +
+ priv_req->start_trb * TRB_SIZE),
+ &priv_dev->regs->ep_traddr);
+
+ cdns3_dbg(priv_ep->cdns3_dev, "Update ep_trbaddr for %s to %08x\n",
+ priv_ep->name, readl(&priv_dev->regs->ep_traddr));
+
+ priv_ep->flags &= ~EP_UPDATE_EP_TRBADDR;
+ }
+
+ if (!priv_ep->wa1_set && !(priv_ep->flags & EP_STALL)) {
+ trace_cdns3_ring(priv_ep);
+ /*clearing TRBERR and EP_STS_DESCMIS before seting DRDY*/
+ writel(EP_STS_TRBERR | EP_STS_DESCMIS, &priv_dev->regs->ep_sts);
+ writel(EP_CMD_DRDY, &priv_dev->regs->ep_cmd);
+ trace_cdns3_doorbell_epx(priv_ep->name,
+ readl(&priv_dev->regs->ep_traddr));
+ }
+
+ /* WORKAROUND for transition to L0 */
+ __cdns3_gadget_wakeup(priv_dev);
+
+ return 0;
+}
+
+void cdns3_set_hw_configuration(struct cdns3_device *priv_dev)
+{
+ struct cdns3_endpoint *priv_ep;
+ struct usb_ep *ep;
+ int result = 0;
+
+ if (priv_dev->hw_configured_flag)
+ return;
+
+ writel(USB_CONF_CFGSET, &priv_dev->regs->usb_conf);
+ writel(EP_CMD_ERDY | EP_CMD_REQ_CMPL, &priv_dev->regs->ep_cmd);
+
+ cdns3_set_register_bit(&priv_dev->regs->usb_conf,
+ USB_CONF_U1EN | USB_CONF_U2EN);
+
+ /* wait until configuration set */
+ result = cdns3_handshake(&priv_dev->regs->usb_sts,
+ USB_STS_CFGSTS_MASK, 1, 100);
+
+ priv_dev->hw_configured_flag = 1;
+
+ list_for_each_entry(ep, &priv_dev->gadget.ep_list, ep_list) {
+ if (ep->enabled) {
+ priv_ep = ep_to_cdns3_ep(ep);
+ cdns3_start_all_request(priv_dev, priv_ep);
+ }
+ }
+}
+
+/**
+ * cdns3_request_handled - check whether request has been handled by DMA
+ *
+ * @priv_ep: extended endpoint object.
+ * @priv_req: request object for checking
+ *
+ * Endpoint must be selected before invoking this function.
+ *
+ * Returns false if request has not been handled by DMA, else returns true.
+ *
+ * SR - start ring
+ * ER - end ring
+ * DQ = priv_ep->dequeue - dequeue position
+ * EQ = priv_ep->enqueue - enqueue position
+ * ST = priv_req->start_trb - index of first TRB in transfer ring
+ * ET = priv_req->end_trb - index of last TRB in transfer ring
+ * CI = current_index - index of processed TRB by DMA.
+ *
+ * As first step, function checks if cycle bit for priv_req->start_trb is
+ * correct.
+ *
+ * some rules:
+ * 1. priv_ep->dequeue never exceed current_index.
+ * 2 priv_ep->enqueue never exceed priv_ep->dequeue
+ * 3. exception: priv_ep->enqueue == priv_ep->dequeue
+ * and priv_ep->free_trbs is zero.
+ * This case indicate that TR is full.
+ *
+ * Then We can split recognition into two parts:
+ * Case 1 - priv_ep->dequeue < current_index
+ * SR ... EQ ... DQ ... CI ... ER
+ * SR ... DQ ... CI ... EQ ... ER
+ *
+ * Request has been handled by DMA if ST and ET is between DQ and CI.
+ *
+ * Case 2 - priv_ep->dequeue > current_index
+ * This situation take place when CI go through the LINK TRB at the end of
+ * transfer ring.
+ * SR ... CI ... EQ ... DQ ... ER
+ *
+ * Request has been handled by DMA if ET is less then CI or
+ * ET is greater or equal DQ.
+ */
+static bool cdns3_request_handled(struct cdns3_endpoint *priv_ep,
+ struct cdns3_request *priv_req)
+{
+ struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ struct cdns3_trb *trb = priv_req->trb;
+ int current_index = 0;
+ int handled = 0;
+ int doorbell;
+
+ current_index = cdns3_get_dma_pos(priv_dev, priv_ep);
+ doorbell = !!(readl(&priv_dev->regs->ep_cmd) & EP_CMD_DRDY);
+
+ trb = &priv_ep->trb_pool[priv_req->start_trb];
+
+ if ((trb->control & TRB_CYCLE) != priv_ep->ccs)
+ goto finish;
+
+ if (doorbell == 1 && current_index == priv_ep->dequeue)
+ goto finish;
+
+ /* The corner case for TRBS_PER_SEGMENT equal 2). */
+ if (TRBS_PER_SEGMENT == 2 && priv_ep->type != USB_ENDPOINT_XFER_ISOC) {
+ handled = 1;
+ goto finish;
+ }
+
+ if (priv_ep->enqueue == priv_ep->dequeue &&
+ priv_ep->free_trbs == 0) {
+ handled = 1;
+ } else if (priv_ep->dequeue < current_index) {
+ if ((current_index == (priv_ep->num_trbs - 1)) &&
+ !priv_ep->dequeue)
+ goto finish;
+
+ if (priv_req->end_trb >= priv_ep->dequeue &&
+ priv_req->end_trb < current_index)
+ handled = 1;
+ } else if (priv_ep->dequeue > current_index) {
+ if (priv_req->end_trb < current_index ||
+ priv_req->end_trb >= priv_ep->dequeue)
+ handled = 1;
+ }
+
+finish:
+ trace_cdns3_request_handled(priv_req, current_index, handled);
+
+ return handled;
+}
+
+static void cdns3_transfer_completed(struct cdns3_device *priv_dev,
+ struct cdns3_endpoint *priv_ep)
+{
+ struct cdns3_request *priv_req;
+ struct usb_request *request;
+ struct cdns3_trb *trb;
+
+ while (!list_empty(&priv_ep->pending_req_list)) {
+ request = cdns3_next_request(&priv_e