diff options
Diffstat (limited to 'kernel/drivers/usb/host/whci/pzl.c')
| -rw-r--r-- | kernel/drivers/usb/host/whci/pzl.c | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/kernel/drivers/usb/host/whci/pzl.c b/kernel/drivers/usb/host/whci/pzl.c new file mode 100644 index 000000000..33c5580b4 --- /dev/null +++ b/kernel/drivers/usb/host/whci/pzl.c @@ -0,0 +1,417 @@ +/* + * Wireless Host Controller (WHC) periodic schedule management. + * + * Copyright (C) 2007 Cambridge Silicon Radio Ltd. + * + * 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, see <http://www.gnu.org/licenses/>. + */ +#include <linux/kernel.h> +#include <linux/gfp.h> +#include <linux/dma-mapping.h> +#include <linux/uwb/umc.h> +#include <linux/usb.h> + +#include "../../wusbcore/wusbhc.h" + +#include "whcd.h" + +static void update_pzl_pointers(struct whc *whc, int period, u64 addr) +{ + switch (period) { + case 0: + whc_qset_set_link_ptr(&whc->pz_list[0], addr); + whc_qset_set_link_ptr(&whc->pz_list[2], addr); + whc_qset_set_link_ptr(&whc->pz_list[4], addr); + whc_qset_set_link_ptr(&whc->pz_list[6], addr); + whc_qset_set_link_ptr(&whc->pz_list[8], addr); + whc_qset_set_link_ptr(&whc->pz_list[10], addr); + whc_qset_set_link_ptr(&whc->pz_list[12], addr); + whc_qset_set_link_ptr(&whc->pz_list[14], addr); + break; + case 1: + whc_qset_set_link_ptr(&whc->pz_list[1], addr); + whc_qset_set_link_ptr(&whc->pz_list[5], addr); + whc_qset_set_link_ptr(&whc->pz_list[9], addr); + whc_qset_set_link_ptr(&whc->pz_list[13], addr); + break; + case 2: + whc_qset_set_link_ptr(&whc->pz_list[3], addr); + whc_qset_set_link_ptr(&whc->pz_list[11], addr); + break; + case 3: + whc_qset_set_link_ptr(&whc->pz_list[7], addr); + break; + case 4: + whc_qset_set_link_ptr(&whc->pz_list[15], addr); + break; + } +} + +/* + * Return the 'period' to use for this qset. The minimum interval for + * the endpoint is used so whatever urbs are submitted the device is + * polled often enough. + */ +static int qset_get_period(struct whc *whc, struct whc_qset *qset) +{ + uint8_t bInterval = qset->ep->desc.bInterval; + + if (bInterval < 6) + bInterval = 6; + if (bInterval > 10) + bInterval = 10; + return bInterval - 6; +} + +static void qset_insert_in_sw_list(struct whc *whc, struct whc_qset *qset) +{ + int period; + + period = qset_get_period(whc, qset); + + qset_clear(whc, qset); + list_move(&qset->list_node, &whc->periodic_list[period]); + qset->in_sw_list = true; +} + +static void pzl_qset_remove(struct whc *whc, struct whc_qset *qset) +{ + list_move(&qset->list_node, &whc->periodic_removed_list); + qset->in_hw_list = false; + qset->in_sw_list = false; +} + +/** + * pzl_process_qset - process any recently inactivated or halted qTDs + * in a qset. + * + * After inactive qTDs are removed, new qTDs can be added if the + * urb queue still contains URBs. + * + * Returns the schedule updates required. + */ +static enum whc_update pzl_process_qset(struct whc *whc, struct whc_qset *qset) +{ + enum whc_update update = 0; + uint32_t status = 0; + + while (qset->ntds) { + struct whc_qtd *td; + int t; + + t = qset->td_start; + td = &qset->qtd[qset->td_start]; + status = le32_to_cpu(td->status); + + /* + * Nothing to do with a still active qTD. + */ + if (status & QTD_STS_ACTIVE) + break; + + if (status & QTD_STS_HALTED) { + /* Ug, an error. */ + process_halted_qtd(whc, qset, td); + /* A halted qTD always triggers an update + because the qset was either removed or + reactivated. */ + update |= WHC_UPDATE_UPDATED; + goto done; + } + + /* Mmm, a completed qTD. */ + process_inactive_qtd(whc, qset, td); + } + + if (!qset->remove) + update |= qset_add_qtds(whc, qset); + +done: + /* + * If there are no qTDs in this qset, remove it from the PZL. + */ + if (qset->remove && qset->ntds == 0) { + pzl_qset_remove(whc, qset); + update |= WHC_UPDATE_REMOVED; + } + + return update; +} + +/** + * pzl_start - start the periodic schedule + * @whc: the WHCI host controller + * + * The PZL must be valid (e.g., all entries in the list should have + * the T bit set). + */ +void pzl_start(struct whc *whc) +{ + le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE); + + whc_write_wusbcmd(whc, WUSBCMD_PERIODIC_EN, WUSBCMD_PERIODIC_EN); + whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS, + WUSBSTS_PERIODIC_SCHED, WUSBSTS_PERIODIC_SCHED, + 1000, "start PZL"); +} + +/** + * pzl_stop - stop the periodic schedule + * @whc: the WHCI host controller + */ +void pzl_stop(struct whc *whc) +{ + whc_write_wusbcmd(whc, WUSBCMD_PERIODIC_EN, 0); + whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS, + WUSBSTS_PERIODIC_SCHED, 0, + 1000, "stop PZL"); +} + +/** + * pzl_update - request a PZL update and wait for the hardware to be synced + * @whc: the WHCI HC + * @wusbcmd: WUSBCMD value to start the update. + * + * If the WUSB HC is inactive (i.e., the PZL is stopped) then the + * update must be skipped as the hardware may not respond to update + * requests. + */ +void pzl_update(struct whc *whc, uint32_t wusbcmd) +{ + struct wusbhc *wusbhc = &whc->wusbhc; + long t; + + mutex_lock(&wusbhc->mutex); + if (wusbhc->active) { + whc_write_wusbcmd(whc, wusbcmd, wusbcmd); + t = wait_event_timeout( + whc->periodic_list_wq, + (le_readl(whc->base + WUSBCMD) & WUSBCMD_PERIODIC_UPDATED) == 0, + msecs_to_jiffies(1000)); + if (t == 0) + whc_hw_error(whc, "PZL update timeout"); + } + mutex_unlock(&wusbhc->mutex); +} + +static void update_pzl_hw_view(struct whc *whc) +{ + struct whc_qset *qset, *t; + int period; + u64 tmp_qh = 0; + + for (period = 0; period < 5; period++) { + list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) { + whc_qset_set_link_ptr(&qset->qh.link, tmp_qh); + tmp_qh = qset->qset_dma; + qset->in_hw_list = true; + } + update_pzl_pointers(whc, period, tmp_qh); + } +} + +/** + * scan_periodic_work - scan the PZL for qsets to process. + * + * Process each qset in the PZL in turn and then signal the WHC that + * the PZL has been updated. + * + * Then start, stop or update the periodic schedule as required. + */ +void scan_periodic_work(struct work_struct *work) +{ + struct whc *whc = container_of(work, struct whc, periodic_work); + struct whc_qset *qset, *t; + enum whc_update update = 0; + int period; + + spin_lock_irq(&whc->lock); + + for (period = 4; period >= 0; period--) { + list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) { + if (!qset->in_hw_list) + update |= WHC_UPDATE_ADDED; + update |= pzl_process_qset(whc, qset); + } + } + + if (update & (WHC_UPDATE_ADDED | WHC_UPDATE_REMOVED)) + update_pzl_hw_view(whc); + + spin_unlock_irq(&whc->lock); + + if (update) { + uint32_t wusbcmd = WUSBCMD_PERIODIC_UPDATED | WUSBCMD_PERIODIC_SYNCED_DB; + if (update & WHC_UPDATE_REMOVED) + wusbcmd |= WUSBCMD_PERIODIC_QSET_RM; + pzl_update(whc, wusbcmd); + } + + /* + * Now that the PZL is updated, complete the removal of any + * removed qsets. + * + * If the qset was to be reset, do so and reinsert it into the + * PZL if it has pending transfers. + */ + spin_lock_irq(&whc->lock); + + list_for_each_entry_safe(qset, t, &whc->periodic_removed_list, list_node) { + qset_remove_complete(whc, qset); + if (qset->reset) { + qset_reset(whc, qset); + if (!list_empty(&qset->stds)) { + qset_insert_in_sw_list(whc, qset); + queue_work(whc->workqueue, &whc->periodic_work); + } + } + } + + spin_unlock_irq(&whc->lock); +} + +/** + * pzl_urb_enqueue - queue an URB onto the periodic list (PZL) + * @whc: the WHCI host controller + * @urb: the URB to enqueue + * @mem_flags: flags for any memory allocations + * + * The qset for the endpoint is obtained and the urb queued on to it. + * + * Work is scheduled to update the hardware's view of the PZL. + */ +int pzl_urb_enqueue(struct whc *whc, struct urb *urb, gfp_t mem_flags) +{ + struct whc_qset *qset; + int err; + unsigned long flags; + + spin_lock_irqsave(&whc->lock, flags); + + err = usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb); + if (err < 0) { + spin_unlock_irqrestore(&whc->lock, flags); + return err; + } + + qset = get_qset(whc, urb, GFP_ATOMIC); + if (qset == NULL) + err = -ENOMEM; + else + err = qset_add_urb(whc, qset, urb, GFP_ATOMIC); + if (!err) { + if (!qset->in_sw_list && !qset->remove) + qset_insert_in_sw_list(whc, qset); + } else + usb_hcd_unlink_urb_from_ep(&whc->wusbhc.usb_hcd, urb); + + spin_unlock_irqrestore(&whc->lock, flags); + + if (!err) + queue_work(whc->workqueue, &whc->periodic_work); + + return err; +} + +/** + * pzl_urb_dequeue - remove an URB (qset) from the periodic list + * @whc: the WHCI host controller + * @urb: the URB to dequeue + * @status: the current status of the URB + * + * URBs that do yet have qTDs can simply be removed from the software + * queue, otherwise the qset must be removed so the qTDs can be safely + * removed. + */ +int pzl_urb_dequeue(struct whc *whc, struct urb *urb, int status) +{ + struct whc_urb *wurb = urb->hcpriv; + struct whc_qset *qset = wurb->qset; + struct whc_std *std, *t; + bool has_qtd = false; + int ret; + unsigned long flags; + + spin_lock_irqsave(&whc->lock, flags); + + ret = usb_hcd_check_unlink_urb(&whc->wusbhc.usb_hcd, urb, status); + if (ret < 0) + goto out; + + list_for_each_entry_safe(std, t, &qset->stds, list_node) { + if (std->urb == urb) { + if (std->qtd) + has_qtd = true; + qset_free_std(whc, std); + } else + std->qtd = NULL; /* so this std is re-added when the qset is */ + } + + if (has_qtd) { + pzl_qset_remove(whc, qset); + update_pzl_hw_view(whc); + wurb->status = status; + wurb->is_async = false; + queue_work(whc->workqueue, &wurb->dequeue_work); + } else + qset_remove_urb(whc, qset, urb, status); +out: + spin_unlock_irqrestore(&whc->lock, flags); + + return ret; +} + +/** + * pzl_qset_delete - delete a qset from the PZL + */ +void pzl_qset_delete(struct whc *whc, struct whc_qset *qset) +{ + qset->remove = 1; + queue_work(whc->workqueue, &whc->periodic_work); + qset_delete(whc, qset); +} + +/** + * pzl_init - initialize the periodic zone list + * @whc: the WHCI host controller + */ +int pzl_init(struct whc *whc) +{ + int i; + + whc->pz_list = dma_alloc_coherent(&whc->umc->dev, sizeof(u64) * 16, + &whc->pz_list_dma, GFP_KERNEL); + if (whc->pz_list == NULL) + return -ENOMEM; + + /* Set T bit on all elements in PZL. */ + for (i = 0; i < 16; i++) + whc->pz_list[i] = cpu_to_le64(QH_LINK_NTDS(8) | QH_LINK_T); + + le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE); + + return 0; +} + +/** + * pzl_clean_up - free PZL resources + * @whc: the WHCI host controller + * + * The PZL is stopped and empty. + */ +void pzl_clean_up(struct whc *whc) +{ + if (whc->pz_list) + dma_free_coherent(&whc->umc->dev, sizeof(u64) * 16, whc->pz_list, + whc->pz_list_dma); +} |