diff options
| -rw-r--r-- | drivers/dma/pxa_dma.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c index 7da79d030f8e..ddcbbf5cd9e9 100644 --- a/drivers/dma/pxa_dma.c +++ b/drivers/dma/pxa_dma.c @@ -410,6 +410,15 @@ static inline void pxad_init_debugfs(struct pxad_device *pdev) {} static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {} #endif +/* + * In the transition phase where legacy pxa handling is done at the same time as + * mmp_dma, the DMA physical channel split between the 2 DMA providers is done + * through legacy_reserved. Legacy code reserves DMA channels by settings + * corresponding bits in legacy_reserved. + */ +static u32 legacy_reserved; +static u32 legacy_unavailable; + static struct pxad_phy *lookup_phy(struct pxad_chan *pchan) { int prio, i; @@ -430,10 +439,14 @@ static struct pxad_phy *lookup_phy(struct pxad_chan *pchan) for (i = 0; i < pdev->nr_chans; i++) { if (prio != (i & 0xf) >> 2) continue; + if ((i < 32) && (legacy_reserved & BIT(i))) + continue; phy = &pdev->phys[i]; if (!phy->vchan) { phy->vchan = pchan; found = phy; + if (i < 32) + legacy_unavailable |= BIT(i); goto out_unlock; } } @@ -453,6 +466,7 @@ static void pxad_free_phy(struct pxad_chan *chan) struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device); unsigned long flags; u32 reg; + int i; dev_dbg(&chan->vc.chan.dev->device, "%s(): freeing\n", __func__); @@ -464,6 +478,9 @@ static void pxad_free_phy(struct pxad_chan *chan) writel_relaxed(0, chan->phy->base + reg); spin_lock_irqsave(&pdev->phy_lock, flags); + for (i = 0; i < 32; i++) + if (chan->phy == &pdev->phys[i]) + legacy_unavailable &= ~BIT(i); chan->phy->vchan = NULL; chan->phy = NULL; spin_unlock_irqrestore(&pdev->phy_lock, flags); @@ -694,6 +711,8 @@ static irqreturn_t pxad_int_handler(int irq, void *dev_id) i = __ffs(dint); dint &= (dint - 1); phy = &pdev->phys[i]; + if ((i < 32) && (legacy_reserved & BIT(i))) + continue; if (pxad_chan_handler(irq, phy) == IRQ_HANDLED) ret = IRQ_HANDLED; } @@ -1432,6 +1451,15 @@ bool pxad_filter_fn(struct dma_chan *chan, void *param) } EXPORT_SYMBOL_GPL(pxad_filter_fn); +int pxad_toggle_reserved_channel(int legacy_channel) +{ + if (legacy_unavailable & (BIT(legacy_channel))) + return -EBUSY; + legacy_reserved ^= BIT(legacy_channel); + return 0; +} +EXPORT_SYMBOL_GPL(pxad_toggle_reserved_channel); + module_platform_driver(pxad_driver); MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver"); |