/*
* 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/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);
}
