diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c index af0a80ddf5948c232950b5e72b5652327cde4b4a..0e79eebfcbb7ac41541b659fc749720d3a0824d2 100644 --- a/drivers/thunderbolt/nhi.c +++ b/drivers/thunderbolt/nhi.c @@ -26,6 +26,8 @@ * use this ring for anything else. */ #define RING_E2E_UNUSED_HOPID 2 +/* HopIDs 0-7 are reserved by the Thunderbolt protocol */ +#define RING_FIRST_USABLE_HOPID 8 /* * Minimal number of vectors when we use MSI-X. Two for control channel @@ -411,6 +413,62 @@ static void ring_release_msix(struct tb_ring *ring) ring->irq = 0; } +static int nhi_alloc_hop(struct tb_nhi *nhi, struct tb_ring *ring) +{ + int ret = 0; + + spin_lock_irq(&nhi->lock); + + if (ring->hop < 0) { + unsigned int i; + + /* + * Automatically allocate HopID from the non-reserved + * range 8 .. hop_count - 1. + */ + for (i = RING_FIRST_USABLE_HOPID; i < nhi->hop_count; i++) { + if (ring->is_tx) { + if (!nhi->tx_rings[i]) { + ring->hop = i; + break; + } + } else { + if (!nhi->rx_rings[i]) { + ring->hop = i; + break; + } + } + } + } + + if (ring->hop < 0 || ring->hop >= nhi->hop_count) { + dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop); + ret = -EINVAL; + goto err_unlock; + } + if (ring->is_tx && nhi->tx_rings[ring->hop]) { + dev_warn(&nhi->pdev->dev, "TX hop %d already allocated\n", + ring->hop); + ret = -EBUSY; + goto err_unlock; + } else if (!ring->is_tx && nhi->rx_rings[ring->hop]) { + dev_warn(&nhi->pdev->dev, "RX hop %d already allocated\n", + ring->hop); + ret = -EBUSY; + goto err_unlock; + } + + if (ring->is_tx) + nhi->tx_rings[ring->hop] = ring; + else + nhi->rx_rings[ring->hop] = ring; + +err_unlock: + spin_unlock_irq(&nhi->lock); + + return ret; +} + static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size, bool transmit, unsigned int flags, u16 sof_mask, u16 eof_mask, @@ -456,28 +514,12 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size, if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND)) goto err_free_descs; - spin_lock_irq(&nhi->lock); - if (hop >= nhi->hop_count) { - dev_WARN(&nhi->pdev->dev, "invalid hop: %d\n", hop); + if (nhi_alloc_hop(nhi, ring)) goto err_release_msix; - } - if (transmit && nhi->tx_rings[hop]) { - dev_WARN(&nhi->pdev->dev, "TX hop %d already allocated\n", hop); - goto err_release_msix; - } else if (!transmit && nhi->rx_rings[hop]) { - dev_WARN(&nhi->pdev->dev, "RX hop %d already allocated\n", hop); - goto err_release_msix; - } - if (transmit) - nhi->tx_rings[hop] = ring; - else - nhi->rx_rings[hop] = ring; - spin_unlock_irq(&nhi->lock); return ring; err_release_msix: - spin_unlock_irq(&nhi->lock); ring_release_msix(ring); err_free_descs: dma_free_coherent(&ring->nhi->pdev->dev, @@ -506,7 +548,7 @@ EXPORT_SYMBOL_GPL(tb_ring_alloc_tx); /** * tb_ring_alloc_rx() - Allocate DMA ring for receive * @nhi: Pointer to the NHI the ring is to be allocated - * @hop: HopID (ring) to allocate + * @hop: HopID (ring) to allocate. Pass %-1 for automatic allocation. * @size: Number of entries in the ring * @flags: Flags for the ring * @sof_mask: Mask of PDF values that start a frame