From b2d8984f3e7c84303e4d1cbd40d9e8cefd3c9737 Mon Sep 17 00:00:00 2001 From: Vinod Koul Date: Tue, 5 Apr 2016 15:31:33 -0700 Subject: [PATCH 1/5] dmaengine: add DMA_CYCLIC to dma_get_slave_caps dma_get_slave_caps() API only checked for slave capability where we use slave capabilities for cyclic dma operations as well, so we should add the cyclic case here too. Signed-off-by: Vinod Koul --- drivers/dma/dmaengine.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 0cb259c59916..3e55755e0ff1 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -482,7 +482,8 @@ int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps) device = chan->device; /* check if the channel supports slave transactions */ - if (!test_bit(DMA_SLAVE, device->cap_mask.bits)) + if ((!test_bit(DMA_SLAVE, device->cap_mask.bits)) || + (!test_bit(DMA_CYCLIC, device->cap_mask.bits))) return -ENXIO; /* From 757d12e5849be549076901b0d33c60d5f360269c Mon Sep 17 00:00:00 2001 From: Vinod Koul Date: Tue, 12 Apr 2016 21:07:06 +0530 Subject: [PATCH 2/5] dmaengine: ensure dmaengine helpers check valid callback dmaengine has various device callbacks and exposes helper functions to invoke these. These helpers should check if channel, device and callback is valid or not before invoking them. Reported-by: Jon Hunter Signed-off-by: Vinod Koul --- include/linux/dmaengine.h | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 017433712833..30de0197263a 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -804,6 +804,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single( sg_dma_address(&sg) = buf; sg_dma_len(&sg) = len; + if (!chan || !chan->device || !chan->device->device_prep_slave_sg) + return NULL; + return chan->device->device_prep_slave_sg(chan, &sg, 1, dir, flags, NULL); } @@ -812,6 +815,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg( struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction dir, unsigned long flags) { + if (!chan || !chan->device || !chan->device->device_prep_slave_sg) + return NULL; + return chan->device->device_prep_slave_sg(chan, sgl, sg_len, dir, flags, NULL); } @@ -823,6 +829,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg( enum dma_transfer_direction dir, unsigned long flags, struct rio_dma_ext *rio_ext) { + if (!chan || !chan->device || !chan->device->device_prep_slave_sg) + return NULL; + return chan->device->device_prep_slave_sg(chan, sgl, sg_len, dir, flags, rio_ext); } @@ -833,6 +842,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic( size_t period_len, enum dma_transfer_direction dir, unsigned long flags) { + if (!chan || !chan->device || !chan->device->device_prep_dma_cyclic) + return NULL; + return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len, period_len, dir, flags); } @@ -841,6 +853,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma( struct dma_chan *chan, struct dma_interleaved_template *xt, unsigned long flags) { + if (!chan || !chan->device || !chan->device->device_prep_interleaved_dma) + return NULL; + return chan->device->device_prep_interleaved_dma(chan, xt, flags); } @@ -848,7 +863,7 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset( struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags) { - if (!chan || !chan->device) + if (!chan || !chan->device || !chan->device->device_prep_dma_memset) return NULL; return chan->device->device_prep_dma_memset(chan, dest, value, @@ -861,6 +876,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg( struct scatterlist *src_sg, unsigned int src_nents, unsigned long flags) { + if (!chan || !chan->device || !chan->device->device_prep_dma_sg) + return NULL; + return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents, src_sg, src_nents, flags); } From dd4e91d538b3d16d5241575a3fb654a9aa50392c Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Tue, 10 May 2016 20:43:34 +0300 Subject: [PATCH 3/5] dmaengine: slave means at least one of DMA_SLAVE, DMA_CYCLIC When check for capabilities recognize slave support by either DMA_SLAVE or DMA_CYCLIC bit set. If we don't do that the user can't get a normally worked DMA support for engines that doesn't have one of the mentioned bits set. Signed-off-by: Andy Shevchenko Signed-off-by: Vinod Koul --- drivers/dma/dmaengine.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 3e55755e0ff1..42ef3457f39e 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -482,8 +482,8 @@ int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps) device = chan->device; /* check if the channel supports slave transactions */ - if ((!test_bit(DMA_SLAVE, device->cap_mask.bits)) || - (!test_bit(DMA_CYCLIC, device->cap_mask.bits))) + if (!(test_bit(DMA_SLAVE, device->cap_mask.bits) || + test_bit(DMA_CYCLIC, device->cap_mask.bits))) return -ENXIO; /* From d57d3a48ca784615e839475d8bdf8f3cecf77c8d Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Wed, 11 May 2016 13:39:27 -0400 Subject: [PATCH 4/5] dmaengine: core: Use IS_ENABLED() instead of checking for built-in or module The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either built-in or as a module, use that macro instead of open coding the same. Signed-off-by: Javier Martinez Canillas Signed-off-by: Vinod Koul --- drivers/dma/dmaengine.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 42ef3457f39e..2432c2a55570 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -863,12 +863,12 @@ static bool device_has_all_tx_types(struct dma_device *device) return false; #endif - #if defined(CONFIG_ASYNC_MEMCPY) || defined(CONFIG_ASYNC_MEMCPY_MODULE) + #if IS_ENABLED(CONFIG_ASYNC_MEMCPY) if (!dma_has_cap(DMA_MEMCPY, device->cap_mask)) return false; #endif - #if defined(CONFIG_ASYNC_XOR) || defined(CONFIG_ASYNC_XOR_MODULE) + #if IS_ENABLED(CONFIG_ASYNC_XOR) if (!dma_has_cap(DMA_XOR, device->cap_mask)) return false; @@ -878,7 +878,7 @@ static bool device_has_all_tx_types(struct dma_device *device) #endif #endif - #if defined(CONFIG_ASYNC_PQ) || defined(CONFIG_ASYNC_PQ_MODULE) + #if IS_ENABLED(CONFIG_ASYNC_PQ) if (!dma_has_cap(DMA_PQ, device->cap_mask)) return false; From 20ea6be6bffd4da8cfe3aeea9e6a090f346a54da Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Niklas=20S=C3=B6derlund?= Date: Wed, 11 May 2016 15:15:11 +0200 Subject: [PATCH 5/5] dmaengine: of_dma: approximate an average distribution MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently the following DT description would result in dmac0 always being tried first and dmac1 second if dmac0 was unavailable. This results in heavier use of dmac0 then of dmac1. This patch adds an approximate average distribution over the two nodes lessening the load of anyone of them. i2c6: i2c@e60b0000 { ... dmas = <&dmac0 0x77>, <&dmac0 0x78>, <&dmac1 0x77>, <&dmac1 0x78>; dma-names = "tx", "rx", "tx", "rx"; ... }; Signed-off-by: Arnd Bergmann Signed-off-by: Niklas Söderlund Suggested-by: Arnd Bergmann Signed-off-by: Vinod Koul --- drivers/dma/of-dma.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c index 1e1f2986eba8..faae0bfe1109 100644 --- a/drivers/dma/of-dma.c +++ b/drivers/dma/of-dma.c @@ -240,8 +240,9 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np, struct of_phandle_args dma_spec; struct of_dma *ofdma; struct dma_chan *chan; - int count, i; + int count, i, start; int ret_no_channel = -ENODEV; + static atomic_t last_index; if (!np || !name) { pr_err("%s: not enough information provided\n", __func__); @@ -259,8 +260,15 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np, return ERR_PTR(-ENODEV); } + /* + * approximate an average distribution across multiple + * entries with the same name + */ + start = atomic_inc_return(&last_index); for (i = 0; i < count; i++) { - if (of_dma_match_channel(np, name, i, &dma_spec)) + if (of_dma_match_channel(np, name, + (i + start) % count, + &dma_spec)) continue; mutex_lock(&of_dma_lock);