From ec6644d6325b5a38525f1d5b20fd4bf7db05cf2a Mon Sep 17 00:00:00 2001 From: Kim Phillips Date: Thu, 17 Jul 2008 20:16:40 +0800 Subject: crypto: talitos - Preempt overflow interrupts add requests pending/submit count to prevent request queue full condition by preempting h/w overflow interrupts in software. We do this due to the delay in the delivery and handling of the channel overflow error interrupt. Signed-off-by: Kim Phillips Acked-by: Lee Nipper Signed-off-by: Herbert Xu --- drivers/crypto/talitos.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) (limited to 'drivers/crypto/talitos.c') diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c index f644fba35c8c..fdb0680f6ffe 100644 --- a/drivers/crypto/talitos.c +++ b/drivers/crypto/talitos.c @@ -99,6 +99,9 @@ struct talitos_private { /* next channel to be assigned next incoming descriptor */ atomic_t last_chan; + /* per-channel number of requests pending in channel h/w fifo */ + atomic_t *submit_count; + /* per-channel request fifo */ struct talitos_request **fifo; @@ -263,15 +266,15 @@ static int talitos_submit(struct device *dev, struct talitos_desc *desc, spin_lock_irqsave(&priv->head_lock[ch], flags); - head = priv->head[ch]; - request = &priv->fifo[ch][head]; - - if (request->desc) { - /* request queue is full */ + if (!atomic_inc_not_zero(&priv->submit_count[ch])) { + /* h/w fifo is full */ spin_unlock_irqrestore(&priv->head_lock[ch], flags); return -EAGAIN; } + head = priv->head[ch]; + request = &priv->fifo[ch][head]; + /* map descriptor and save caller data */ request->dma_desc = dma_map_single(dev, desc, sizeof(*desc), DMA_BIDIRECTIONAL); @@ -335,6 +338,9 @@ static void flush_channel(struct device *dev, int ch, int error, int reset_ch) priv->tail[ch] = (tail + 1) & (priv->fifo_len - 1); spin_unlock_irqrestore(&priv->tail_lock[ch], flags); + + atomic_dec(&priv->submit_count[ch]); + saved_req.callback(dev, saved_req.desc, saved_req.context, status); /* channel may resume processing in single desc error case */ @@ -1337,6 +1343,7 @@ static int __devexit talitos_remove(struct of_device *ofdev) if (hw_supports(dev, DESC_HDR_SEL0_RNG)) talitos_unregister_rng(dev); + kfree(priv->submit_count); kfree(priv->tail); kfree(priv->head); @@ -1501,6 +1508,16 @@ static int talitos_probe(struct of_device *ofdev, } } + priv->submit_count = kmalloc(sizeof(int) * priv->num_channels, + GFP_KERNEL); + if (!priv->submit_count) { + dev_err(dev, "failed to allocate fifo submit count space\n"); + err = -ENOMEM; + goto err_out; + } + for (i = 0; i < priv->num_channels; i++) + atomic_set(&priv->submit_count[i], -priv->chfifo_len); + priv->head = kzalloc(sizeof(int) * priv->num_channels, GFP_KERNEL); priv->tail = kzalloc(sizeof(int) * priv->num_channels, GFP_KERNEL); if (!priv->head || !priv->tail) { -- cgit v1.2.3