diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/ti/omap-dma.c | 62 |
1 files changed, 58 insertions, 4 deletions
diff --git a/drivers/dma/ti/omap-dma.c b/drivers/dma/ti/omap-dma.c index 7e26f0c3a168..9c5f17a48d46 100644 --- a/drivers/dma/ti/omap-dma.c +++ b/drivers/dma/ti/omap-dma.c @@ -28,6 +28,7 @@ struct omap_dma_config { int lch_end; unsigned int rw_priority:1; unsigned int may_lose_context:1; + unsigned int needs_lch_clear:1; }; struct omap_dma_context { @@ -47,6 +48,8 @@ struct omap_dmadev { struct notifier_block nb; struct omap_dma_context context; int lch_count; + DECLARE_BITMAP(lch_bitmap, OMAP_SDMA_CHANNELS); + struct mutex lch_lock; /* for assigning logical channels */ bool legacy; bool ll123_supported; struct dma_pool *desc_pool; @@ -664,6 +667,37 @@ static irqreturn_t omap_dma_irq(int irq, void *devid) return IRQ_HANDLED; } +static int omap_dma_get_lch(struct omap_dmadev *od, int *lch) +{ + int channel; + + mutex_lock(&od->lch_lock); + channel = find_first_zero_bit(od->lch_bitmap, od->lch_count); + if (channel >= od->lch_count) + goto out_busy; + set_bit(channel, od->lch_bitmap); + mutex_unlock(&od->lch_lock); + + omap_dma_clear_lch(od, channel); + *lch = channel; + + return 0; + +out_busy: + mutex_unlock(&od->lch_lock); + *lch = -EINVAL; + + return -EBUSY; +} + +static void omap_dma_put_lch(struct omap_dmadev *od, int lch) +{ + omap_dma_clear_lch(od, lch); + mutex_lock(&od->lch_lock); + clear_bit(lch, od->lch_bitmap); + mutex_unlock(&od->lch_lock); +} + static int omap_dma_alloc_chan_resources(struct dma_chan *chan) { struct omap_dmadev *od = to_omap_dma_dev(chan->device); @@ -675,15 +709,13 @@ static int omap_dma_alloc_chan_resources(struct dma_chan *chan) ret = omap_request_dma(c->dma_sig, "DMA engine", omap_dma_callback, c, &c->dma_ch); } else { - ret = omap_request_dma(c->dma_sig, "DMA engine", NULL, NULL, - &c->dma_ch); + ret = omap_dma_get_lch(od, &c->dma_ch); } dev_dbg(dev, "allocating channel %u for %u\n", c->dma_ch, c->dma_sig); if (ret >= 0) { omap_dma_assign(od, c, c->dma_ch); - pr_info("XXX %s: assigned lch: %i\n", __func__, c->dma_ch); if (!od->legacy) { unsigned val; @@ -734,7 +766,11 @@ static void omap_dma_free_chan_resources(struct dma_chan *chan) c->channel_base = NULL; od->lch_map[c->dma_ch] = NULL; vchan_free_chan_resources(&c->vc); - omap_free_dma(c->dma_ch); + + if (od->legacy) + omap_free_dma(c->dma_ch); + else + omap_dma_put_lch(od, c->dma_ch); dev_dbg(od->ddev.dev, "freeing channel %u used for %u\n", c->dma_ch, c->dma_sig); @@ -1574,6 +1610,7 @@ static int omap_dma_probe(struct platform_device *pdev) struct omap_dmadev *od; struct resource *res; int rc, i, irq; + u32 val; od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL); if (!od) @@ -1628,6 +1665,7 @@ static int omap_dma_probe(struct platform_device *pdev) od->ddev.max_burst = SZ_16M - 1; /* CCEN: 24bit unsigned */ od->ddev.dev = &pdev->dev; INIT_LIST_HEAD(&od->ddev.channels); + mutex_init(&od->lch_lock); spin_lock_init(&od->lock); spin_lock_init(&od->irq_lock); @@ -1654,6 +1692,17 @@ static int omap_dma_probe(struct platform_device *pdev) od->lch_count = OMAP_SDMA_CHANNELS; } + /* Mask of allowed logical channels */ + if (pdev->dev.of_node && !of_property_read_u32(pdev->dev.of_node, + "dma-channel-mask", + &val)) { + /* Tag channels not in mask as reserved */ + val = ~val; + bitmap_from_arr32(od->lch_bitmap, &val, od->lch_count); + } + if (od->plat->dma_attr->dev_caps & HS_CHANNELS_RESERVED) + bitmap_set(od->lch_bitmap, 0, 2); + od->lch_map = devm_kcalloc(&pdev->dev, od->lch_count, sizeof(*od->lch_map), GFP_KERNEL); @@ -1772,28 +1821,33 @@ static int omap_dma_remove(struct platform_device *pdev) static const struct omap_dma_config omap2420_data = { .lch_end = CCFN, .rw_priority = true, + .needs_lch_clear = true, }; static const struct omap_dma_config omap2430_data = { .lch_end = CCFN, .rw_priority = true, + .needs_lch_clear = true, }; static const struct omap_dma_config omap3430_data = { .lch_end = CCFN, .rw_priority = true, + .needs_lch_clear = true, .may_lose_context = true, }; static const struct omap_dma_config omap3630_data = { .lch_end = CCDN, .rw_priority = true, + .needs_lch_clear = true, .may_lose_context = true, }; static const struct omap_dma_config omap4_data = { .lch_end = CCDN, .rw_priority = true, + .needs_lch_clear = true, }; static const struct of_device_id omap_dma_match[] = { |