#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/err.h>
+#include <linux/pm_runtime.h>
#include "dmaengine.h"
#define PL330_MAX_CHAN 8
#define NR_DEFAULT_DESC 16
+/* Delay for runtime PM autosuspend, ms */
+#define PL330_AUTOSUSPEND_DELAY 20
+
/* Populated by the PL330 core driver for DMA API driver's info */
struct pl330_config {
u32 periph_id;
struct pl330_dmac *pl330 = thrd->dmac;
struct _xfer_spec xs;
unsigned long flags;
- void __iomem *regs;
unsigned idx;
u32 ccr;
int ret = 0;
- /* No Req or Unacquired Channel or DMAC */
- if (!desc || !thrd || thrd->free)
- return -EINVAL;
-
- regs = thrd->dmac->base;
-
if (pl330->state == DYING
|| pl330->dmac_tbd.reset_chan & (1 << thrd->id)) {
dev_info(thrd->dmac->ddma.dev, "%s:%d\n",
struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data;
struct dma_pl330_desc *desc, *_dt;
unsigned long flags;
+ bool power_down = false;
spin_lock_irqsave(&pch->lock, flags);
/* Try to submit a req imm. next to the last completed cookie */
fill_queue(pch);
- /* Make sure the PL330 Channel thread is active */
- spin_lock(&pch->thread->dmac->lock);
- _start(pch->thread);
- spin_unlock(&pch->thread->dmac->lock);
+ if (list_empty(&pch->work_list)) {
+ spin_lock(&pch->thread->dmac->lock);
+ _stop(pch->thread);
+ spin_unlock(&pch->thread->dmac->lock);
+ power_down = true;
+ } else {
+ /* Make sure the PL330 Channel thread is active */
+ spin_lock(&pch->thread->dmac->lock);
+ _start(pch->thread);
+ spin_unlock(&pch->thread->dmac->lock);
+ }
while (!list_empty(&pch->completed_list)) {
dma_async_tx_callback callback;
if (pch->cyclic) {
desc->status = PREP;
list_move_tail(&desc->node, &pch->work_list);
+ if (power_down) {
+ spin_lock(&pch->thread->dmac->lock);
+ _start(pch->thread);
+ spin_unlock(&pch->thread->dmac->lock);
+ power_down = false;
+ }
} else {
desc->status = FREE;
list_move_tail(&desc->node, &pch->dmac->desc_pool);
}
}
spin_unlock_irqrestore(&pch->lock, flags);
+
+ /* If work list empty, power down */
+ if (power_down) {
+ pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
+ pm_runtime_put_autosuspend(pch->dmac->ddma.dev);
+ }
}
bool pl330_filter(struct dma_chan *chan, void *param)
switch (cmd) {
case DMA_TERMINATE_ALL:
+ pm_runtime_get_sync(pl330->ddma.dev);
spin_lock_irqsave(&pch->lock, flags);
spin_lock(&pl330->lock);
dma_cookie_complete(&desc->txd);
}
+ if (!list_empty(&pch->work_list))
+ pm_runtime_put(pl330->ddma.dev);
+
list_splice_tail_init(&pch->submitted_list, &pl330->desc_pool);
list_splice_tail_init(&pch->work_list, &pl330->desc_pool);
list_splice_tail_init(&pch->completed_list, &pl330->desc_pool);
spin_unlock_irqrestore(&pch->lock, flags);
+ pm_runtime_mark_last_busy(pl330->ddma.dev);
+ pm_runtime_put_autosuspend(pl330->ddma.dev);
break;
case DMA_SLAVE_CONFIG:
slave_config = (struct dma_slave_config *)arg;
tasklet_kill(&pch->task);
+ pm_runtime_get_sync(pch->dmac->ddma.dev);
spin_lock_irqsave(&pch->lock, flags);
pl330_release_channel(pch->thread);
list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
spin_unlock_irqrestore(&pch->lock, flags);
+ pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
+ pm_runtime_put_autosuspend(pch->dmac->ddma.dev);
}
static enum dma_status
unsigned long flags;
spin_lock_irqsave(&pch->lock, flags);
+ if (list_empty(&pch->work_list)) {
+ /*
+ * Warn on nothing pending. Empty submitted_list may
+ * break our pm_runtime usage counter as it is
+ * updated on work_list emptiness status.
+ */
+ WARN_ON(list_empty(&pch->submitted_list));
+ pm_runtime_get_sync(pch->dmac->ddma.dev);
+ }
list_splice_tail_init(&pch->submitted_list, &pch->work_list);
spin_unlock_irqrestore(&pch->lock, flags);
return 0;
}
+/*
+ * Runtime PM callbacks are provided by amba/bus.c driver.
+ *
+ * It is assumed here that IRQ safe runtime PM is chosen in probe and amba
+ * bus driver will only disable/enable the clock in runtime PM callbacks.
+ */
+static int __maybe_unused pl330_suspend(struct device *dev)
+{
+ struct amba_device *pcdev = to_amba_device(dev);
+
+ pm_runtime_disable(dev);
+
+ if (!pm_runtime_status_suspended(dev)) {
+ /* amba did not disable the clock */
+ amba_pclk_disable(pcdev);
+ }
+ amba_pclk_unprepare(pcdev);
+
+ return 0;
+}
+
+static int __maybe_unused pl330_resume(struct device *dev)
+{
+ struct amba_device *pcdev = to_amba_device(dev);
+ int ret;
+
+ ret = amba_pclk_prepare(pcdev);
+ if (ret)
+ return ret;
+
+ if (!pm_runtime_status_suspended(dev))
+ ret = amba_pclk_enable(pcdev);
+
+ pm_runtime_enable(dev);
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(pl330_pm, pl330_suspend, pl330_resume);
+
static int
pl330_probe(struct amba_device *adev, const struct amba_id *id)
{
pcfg->data_buf_dep, pcfg->data_bus_width / 8, pcfg->num_chan,
pcfg->num_peri, pcfg->num_events);
+ pm_runtime_irq_safe(&adev->dev);
+ pm_runtime_use_autosuspend(&adev->dev);
+ pm_runtime_set_autosuspend_delay(&adev->dev, PL330_AUTOSUSPEND_DELAY);
+ pm_runtime_mark_last_busy(&adev->dev);
+ pm_runtime_put_autosuspend(&adev->dev);
+
return 0;
probe_err3:
/* Idle the DMAC */
list_del(&pch->chan.device_node);
/* Flush the channel */
- pl330_control(&pch->chan, DMA_TERMINATE_ALL, 0);
- pl330_free_chan_resources(&pch->chan);
+ if (pch->thread) {
+ pl330_control(&pch->chan, DMA_TERMINATE_ALL, 0);
+ pl330_free_chan_resources(&pch->chan);
+ }
}
probe_err2:
pl330_del(pl330);
struct pl330_dmac *pl330 = amba_get_drvdata(adev);
struct dma_pl330_chan *pch, *_p;
+ pm_runtime_get_noresume(pl330->ddma.dev);
+
if (adev->dev.of_node)
of_dma_controller_free(adev->dev.of_node);
list_del(&pch->chan.device_node);
/* Flush the channel */
- pl330_control(&pch->chan, DMA_TERMINATE_ALL, 0);
- pl330_free_chan_resources(&pch->chan);
+ if (pch->thread) {
+ pl330_control(&pch->chan, DMA_TERMINATE_ALL, 0);
+ pl330_free_chan_resources(&pch->chan);
+ }
}
pl330_del(pl330);
.drv = {
.owner = THIS_MODULE,
.name = "dma-pl330",
+ .pm = &pl330_pm,
},
.id_table = pl330_ids,
.probe = pl330_probe,
git.openpandora.org / pandora-kernel.git / blobdiff