From eb8df543e444492328f506adffc7dfe94111f1bd Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:44 +0200 Subject: dmaengine: mv_xor_v2: handle mv_xor_v2_prep_sw_desc() error properly The mv_xor_v2_prep_sw_desc() is called from a few different places in the driver, but we never take into account the fact that it might return NULL. This commit fixes that, ensuring that we don't panic if there are no more descriptors available. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index a28a01fcba67..e9280207ac19 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -389,6 +389,8 @@ mv_xor_v2_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, __func__, len, &src, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -443,6 +445,8 @@ mv_xor_v2_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, __func__, src_cnt, len, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -491,6 +495,8 @@ mv_xor_v2_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags) container_of(chan, struct mv_xor_v2_device, dmachan); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; /* set the HW descriptor */ hw_descriptor = &sw_desc->hw_desc; -- cgit v1.2.3 From 2aab4e18152cd30cb5d2f4c27629fc8a04aed979 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:45 +0200 Subject: dmaengine: mv_xor_v2: properly handle wrapping in the array of HW descriptors mv_xor_v2_tasklet() is looping over completed HW descriptors. Before the loop, it initializes 'next_pending_hw_desc' to the first HW descriptor to handle, and then the loop simply increments this point, without taking care of wrapping when we reach the last HW descriptor. The 'pending_ptr' index was being wrapped back to 0 at the end, but it wasn't used in each iteration of the loop to calculate next_pending_hw_desc. This commit fixes that, and makes next_pending_hw_desc a variable local to the loop itself. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index e9280207ac19..bdfb36ecff81 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -560,7 +560,6 @@ static void mv_xor_v2_tasklet(unsigned long data) { struct mv_xor_v2_device *xor_dev = (struct mv_xor_v2_device *) data; int pending_ptr, num_of_pending, i; - struct mv_xor_v2_descriptor *next_pending_hw_desc = NULL; struct mv_xor_v2_sw_desc *next_pending_sw_desc = NULL; dev_dbg(xor_dev->dmadev.dev, "%s %d\n", __func__, __LINE__); @@ -568,17 +567,10 @@ static void mv_xor_v2_tasklet(unsigned long data) /* get the pending descriptors parameters */ num_of_pending = mv_xor_v2_get_pending_params(xor_dev, &pending_ptr); - /* next HW descriptor */ - next_pending_hw_desc = xor_dev->hw_desq_virt + pending_ptr; - /* loop over free descriptors */ for (i = 0; i < num_of_pending; i++) { - - if (pending_ptr > MV_XOR_V2_DESC_NUM) - pending_ptr = 0; - - if (next_pending_sw_desc != NULL) - next_pending_hw_desc++; + struct mv_xor_v2_descriptor *next_pending_hw_desc = + xor_dev->hw_desq_virt + pending_ptr; /* get the SW descriptor related to the HW descriptor */ next_pending_sw_desc = @@ -614,6 +606,8 @@ static void mv_xor_v2_tasklet(unsigned long data) /* increment the next descriptor */ pending_ptr++; + if (pending_ptr >= MV_XOR_V2_DESC_NUM) + pending_ptr = 0; } if (num_of_pending != 0) { -- cgit v1.2.3 From bc473da1ed726c975ad47f8d7d27631de11356d8 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:46 +0200 Subject: dmaengine: mv_xor_v2: do not use descriptors not acked by async_tx Descriptors that have not been acknowledged by the async_tx layer should not be re-used, so this commit adjusts the implementation of mv_xor_v2_prep_sw_desc() to skip descriptors for which async_tx_test_ack() is false. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index bdfb36ecff81..cb60e7c4aa16 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -344,6 +344,7 @@ static struct mv_xor_v2_sw_desc * mv_xor_v2_prep_sw_desc(struct mv_xor_v2_device *xor_dev) { struct mv_xor_v2_sw_desc *sw_desc; + bool found = false; /* Lock the channel */ spin_lock_bh(&xor_dev->lock); @@ -355,19 +356,23 @@ mv_xor_v2_prep_sw_desc(struct mv_xor_v2_device *xor_dev) return NULL; } - /* get a free SW descriptor from the SW DESQ */ - sw_desc = list_first_entry(&xor_dev->free_sw_desc, - struct mv_xor_v2_sw_desc, free_list); + list_for_each_entry(sw_desc, &xor_dev->free_sw_desc, free_list) { + if (async_tx_test_ack(&sw_desc->async_tx)) { + found = true; + break; + } + } + + if (!found) { + spin_unlock_bh(&xor_dev->lock); + return NULL; + } + list_del(&sw_desc->free_list); /* Release the channel */ spin_unlock_bh(&xor_dev->lock); - /* set the async tx descriptor */ - dma_async_tx_descriptor_init(&sw_desc->async_tx, &xor_dev->dmachan); - sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit; - async_tx_ack(&sw_desc->async_tx); - return sw_desc; } @@ -785,8 +790,15 @@ static int mv_xor_v2_probe(struct platform_device *pdev) /* add all SW descriptors to the free list */ for (i = 0; i < MV_XOR_V2_DESC_NUM; i++) { - xor_dev->sw_desq[i].idx = i; - list_add(&xor_dev->sw_desq[i].free_list, + struct mv_xor_v2_sw_desc *sw_desc = + xor_dev->sw_desq + i; + sw_desc->idx = i; + dma_async_tx_descriptor_init(&sw_desc->async_tx, + &xor_dev->dmachan); + sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit; + async_tx_ack(&sw_desc->async_tx); + + list_add(&sw_desc->free_list, &xor_dev->free_sw_desc); } -- cgit v1.2.3 From ab2c5f0a77fe49bdb6e307b397496373cb47d2c2 Mon Sep 17 00:00:00 2001 From: Hanna Hawa Date: Fri, 5 May 2017 11:57:47 +0200 Subject: dmaengine: mv_xor_v2: enable XOR engine after its configuration The engine was enabled prior to its configuration, which isn't correct. This patch relocates the activation of the XOR engine, to be after the configuration of the XOR engine. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Hanna Hawa Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index cb60e7c4aa16..211b8c0e3cfb 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -653,9 +653,6 @@ static int mv_xor_v2_descq_init(struct mv_xor_v2_device *xor_dev) writel((xor_dev->hw_desq & 0xFFFF00000000) >> 32, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_BAHR_OFF); - /* enable the DMA engine */ - writel(0, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF); - /* * This is a temporary solution, until we activate the * SMMU. Set the attributes for reading & writing data buffers @@ -699,6 +696,9 @@ static int mv_xor_v2_descq_init(struct mv_xor_v2_device *xor_dev) reg |= MV_XOR_V2_GLOB_PAUSE_AXI_TIME_DIS_VAL; writel(reg, xor_dev->glob_base + MV_XOR_V2_GLOB_PAUSE); + /* enable the DMA engine */ + writel(0, xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_STOP_OFF); + return 0; } -- cgit v1.2.3 From 44d5887a8bf1e86915c8ff647337cb138149da82 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:48 +0200 Subject: dmaengine: mv_xor_v2: fix tx_submit() implementation The mv_xor_v2_tx_submit() gets the next available HW descriptor by calling mv_xor_v2_get_desq_write_ptr(), which reads a HW register telling the next available HW descriptor. This was working fine when HW descriptors were issued for processing directly in tx_submit(). However, as part of the review process of the driver, a change was requested to move the actual kick-off of HW descriptors processing to ->issue_pending(). Due to this, reading the HW register to know the next available HW descriptor no longer works. So instead of using this HW register, we implemented a software index pointing to the next available HW descriptor. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 22 +++++----------------- 1 file changed, 5 insertions(+), 17 deletions(-) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index 211b8c0e3cfb..4684eceea759 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -161,6 +161,7 @@ struct mv_xor_v2_device { struct mv_xor_v2_sw_desc *sw_desq; int desc_size; unsigned int npendings; + unsigned int hw_queue_idx; }; /** @@ -213,18 +214,6 @@ static void mv_xor_v2_set_data_buffers(struct mv_xor_v2_device *xor_dev, } } -/* - * Return the next available index in the DESQ. - */ -static int mv_xor_v2_get_desq_write_ptr(struct mv_xor_v2_device *xor_dev) -{ - /* read the index for the next available descriptor in the DESQ */ - u32 reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_DESQ_ALLOC_OFF); - - return ((reg >> MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_SHIFT) - & MV_XOR_V2_DMA_DESQ_ALLOC_WRPTR_MASK); -} - /* * notify the engine of new descriptors, and update the available index. */ @@ -306,7 +295,6 @@ static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data) static dma_cookie_t mv_xor_v2_tx_submit(struct dma_async_tx_descriptor *tx) { - int desq_ptr; void *dest_hw_desc; dma_cookie_t cookie; struct mv_xor_v2_sw_desc *sw_desc = @@ -322,15 +310,15 @@ mv_xor_v2_tx_submit(struct dma_async_tx_descriptor *tx) spin_lock_bh(&xor_dev->lock); cookie = dma_cookie_assign(tx); - /* get the next available slot in the DESQ */ - desq_ptr = mv_xor_v2_get_desq_write_ptr(xor_dev); - /* copy the HW descriptor from the SW descriptor to the DESQ */ - dest_hw_desc = xor_dev->hw_desq_virt + desq_ptr; + dest_hw_desc = xor_dev->hw_desq_virt + xor_dev->hw_queue_idx; memcpy(dest_hw_desc, &sw_desc->hw_desc, xor_dev->desc_size); xor_dev->npendings++; + xor_dev->hw_queue_idx++; + if (xor_dev->hw_queue_idx >= MV_XOR_V2_DESC_NUM) + xor_dev->hw_queue_idx = 0; spin_unlock_bh(&xor_dev->lock); -- cgit v1.2.3 From 9dd4f319bac25334a869d9276b19eac9e478fd33 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:49 +0200 Subject: dmaengine: mv_xor_v2: remove interrupt coalescing The current implementation of interrupt coalescing doesn't work, because it doesn't configure the coalescing timer, which is needed to make sure we get an interrupt at some point. As a fix for stable, we simply remove the interrupt coalescing functionality. It will be re-introduced properly in a future commit. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 25 ------------------------- 1 file changed, 25 deletions(-) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index 4684eceea759..b133fe29d788 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -246,22 +246,6 @@ static int mv_xor_v2_set_desc_size(struct mv_xor_v2_device *xor_dev) return MV_XOR_V2_EXT_DESC_SIZE; } -/* - * Set the IMSG threshold - */ -static inline -void mv_xor_v2_set_imsg_thrd(struct mv_xor_v2_device *xor_dev, int thrd_val) -{ - u32 reg; - - reg = readl(xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF); - - reg &= (~MV_XOR_V2_DMA_IMSG_THRD_MASK << MV_XOR_V2_DMA_IMSG_THRD_SHIFT); - reg |= (thrd_val << MV_XOR_V2_DMA_IMSG_THRD_SHIFT); - - writel(reg, xor_dev->dma_base + MV_XOR_V2_DMA_IMSG_THRD_OFF); -} - static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data) { struct mv_xor_v2_device *xor_dev = data; @@ -277,12 +261,6 @@ static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data) if (!ndescs) return IRQ_NONE; - /* - * Update IMSG threshold, to disable new IMSG interrupts until - * end of the tasklet - */ - mv_xor_v2_set_imsg_thrd(xor_dev, MV_XOR_V2_DESC_NUM); - /* schedule a tasklet to handle descriptors callbacks */ tasklet_schedule(&xor_dev->irq_tasklet); @@ -607,9 +585,6 @@ static void mv_xor_v2_tasklet(unsigned long data) /* free the descriptores */ mv_xor_v2_free_desc_from_desq(xor_dev, num_of_pending); } - - /* Update IMSG threshold, to enable new IMSG interrupts */ - mv_xor_v2_set_imsg_thrd(xor_dev, 0); } /* -- cgit v1.2.3 From b2d3c270f9f2fb82518ac500a9849c3aaf503852 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 5 May 2017 11:57:50 +0200 Subject: dmaengine: mv_xor_v2: set DMA mask to 40 bits The XORv2 engine on Armada 7K/8K can only access the first 40 bits of the physical address space, so the DMA mask must be set accordingly. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Cc: Signed-off-by: Thomas Petazzoni Signed-off-by: Vinod Koul --- drivers/dma/mv_xor_v2.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/dma/mv_xor_v2.c') diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index b133fe29d788..f3e211f8f6c5 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -693,6 +693,10 @@ static int mv_xor_v2_probe(struct platform_device *pdev) platform_set_drvdata(pdev, xor_dev); + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40)); + if (ret) + return ret; + xor_dev->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(xor_dev->clk) && PTR_ERR(xor_dev->clk) == -EPROBE_DEFER) return -EPROBE_DEFER; -- cgit v1.2.3