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author | Álvaro Fernández Rojas <noltari@gmail.com> | 2016-09-10 14:54:26 +0200 |
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committer | Álvaro Fernández Rojas <noltari@gmail.com> | 2016-09-10 14:54:26 +0200 |
commit | 2b1c6b21b5e6c82ebb55d7fb7df90e60e88cbb14 (patch) | |
tree | ba6d48b4fec219d07110f5d55afc19bc309d2bdb /target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch | |
parent | ac08cb06f6734ebf73ed855cbc836c566f80eaca (diff) | |
download | master-31e0f0ae-2b1c6b21b5e6c82ebb55d7fb7df90e60e88cbb14.tar.gz master-31e0f0ae-2b1c6b21b5e6c82ebb55d7fb7df90e60e88cbb14.tar.bz2 master-31e0f0ae-2b1c6b21b5e6c82ebb55d7fb7df90e60e88cbb14.zip |
brcm2708: update linux 4.4 patches to latest version
As usual these patches were extracted and rebased from the raspberry pi repo:
https://github.com/raspberrypi/linux/tree/rpi-4.4.y
Also adds support for Raspberry Pi Compute Module 3 (untested).
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch')
-rw-r--r-- | target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch | 378 |
1 files changed, 0 insertions, 378 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch b/target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch deleted file mode 100644 index f998a880f2..0000000000 --- a/target/linux/brcm2708/patches-4.4/0397-dmaengine-bcm2835-move-controlblock-chain-generation.patch +++ /dev/null @@ -1,378 +0,0 @@ -From b181092e7661f90e4777e0b858e601a33c1e5af9 Mon Sep 17 00:00:00 2001 -From: Martin Sperl <kernel@martin.sperl.org> -Date: Wed, 16 Mar 2016 12:24:59 -0700 -Subject: [PATCH 397/423] dmaengine: bcm2835: move controlblock chain - generation into separate method - -In preparation of adding slave_sg functionality this patch moves the -generation/allocation of bcm2835_desc and the building of -the corresponding DMA-control-block chain from bcm2835_dma_prep_dma_cyclic -into the newly created method bcm2835_dma_create_cb_chain. - -Signed-off-by: Martin Sperl <kernel@martin.sperl.org> -Reviewed-by: Eric Anholt <eric@anholt.net> -Signed-off-by: Eric Anholt <eric@anholt.net> -Signed-off-by: Vinod Koul <vinod.koul@intel.com> ---- - drivers/dma/bcm2835-dma.c | 294 +++++++++++++++++++++++++++++++--------------- - 1 file changed, 198 insertions(+), 96 deletions(-) - ---- a/drivers/dma/bcm2835-dma.c -+++ b/drivers/dma/bcm2835-dma.c -@@ -88,12 +88,12 @@ struct bcm2835_desc { - struct virt_dma_desc vd; - enum dma_transfer_direction dir; - -- struct bcm2835_cb_entry *cb_list; -- - unsigned int frames; - size_t size; - - bool cyclic; -+ -+ struct bcm2835_cb_entry cb_list[]; - }; - - #define BCM2835_DMA_CS 0x00 -@@ -169,6 +169,13 @@ struct bcm2835_desc { - #define BCM2835_DMA_CHAN(n) ((n) << 8) /* Base address */ - #define BCM2835_DMA_CHANIO(base, n) ((base) + BCM2835_DMA_CHAN(n)) - -+/* how many frames of max_len size do we need to transfer len bytes */ -+static inline size_t bcm2835_dma_frames_for_length(size_t len, -+ size_t max_len) -+{ -+ return DIV_ROUND_UP(len, max_len); -+} -+ - static inline struct bcm2835_dmadev *to_bcm2835_dma_dev(struct dma_device *d) - { - return container_of(d, struct bcm2835_dmadev, ddev); -@@ -185,19 +192,161 @@ static inline struct bcm2835_desc *to_bc - return container_of(t, struct bcm2835_desc, vd.tx); - } - --static void bcm2835_dma_desc_free(struct virt_dma_desc *vd) -+static void bcm2835_dma_free_cb_chain(struct bcm2835_desc *desc) - { -- struct bcm2835_desc *desc = container_of(vd, struct bcm2835_desc, vd); -- int i; -+ size_t i; - - for (i = 0; i < desc->frames; i++) - dma_pool_free(desc->c->cb_pool, desc->cb_list[i].cb, - desc->cb_list[i].paddr); - -- kfree(desc->cb_list); - kfree(desc); - } - -+static void bcm2835_dma_desc_free(struct virt_dma_desc *vd) -+{ -+ bcm2835_dma_free_cb_chain( -+ container_of(vd, struct bcm2835_desc, vd)); -+} -+ -+static void bcm2835_dma_create_cb_set_length( -+ struct bcm2835_chan *chan, -+ struct bcm2835_dma_cb *control_block, -+ size_t len, -+ size_t period_len, -+ size_t *total_len, -+ u32 finalextrainfo) -+{ -+ /* set the length */ -+ control_block->length = len; -+ -+ /* finished if we have no period_length */ -+ if (!period_len) -+ return; -+ -+ /* -+ * period_len means: that we need to generate -+ * transfers that are terminating at every -+ * multiple of period_len - this is typically -+ * used to set the interrupt flag in info -+ * which is required during cyclic transfers -+ */ -+ -+ /* have we filled in period_length yet? */ -+ if (*total_len + control_block->length < period_len) -+ return; -+ -+ /* calculate the length that remains to reach period_length */ -+ control_block->length = period_len - *total_len; -+ -+ /* reset total_length for next period */ -+ *total_len = 0; -+ -+ /* add extrainfo bits in info */ -+ control_block->info |= finalextrainfo; -+} -+ -+/** -+ * bcm2835_dma_create_cb_chain - create a control block and fills data in -+ * -+ * @chan: the @dma_chan for which we run this -+ * @direction: the direction in which we transfer -+ * @cyclic: it is a cyclic transfer -+ * @info: the default info bits to apply per controlblock -+ * @frames: number of controlblocks to allocate -+ * @src: the src address to assign (if the S_INC bit is set -+ * in @info, then it gets incremented) -+ * @dst: the dst address to assign (if the D_INC bit is set -+ * in @info, then it gets incremented) -+ * @buf_len: the full buffer length (may also be 0) -+ * @period_len: the period length when to apply @finalextrainfo -+ * in addition to the last transfer -+ * this will also break some control-blocks early -+ * @finalextrainfo: additional bits in last controlblock -+ * (or when period_len is reached in case of cyclic) -+ * @gfp: the GFP flag to use for allocation -+ */ -+static struct bcm2835_desc *bcm2835_dma_create_cb_chain( -+ struct dma_chan *chan, enum dma_transfer_direction direction, -+ bool cyclic, u32 info, u32 finalextrainfo, size_t frames, -+ dma_addr_t src, dma_addr_t dst, size_t buf_len, -+ size_t period_len, gfp_t gfp) -+{ -+ struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); -+ size_t len = buf_len, total_len; -+ size_t frame; -+ struct bcm2835_desc *d; -+ struct bcm2835_cb_entry *cb_entry; -+ struct bcm2835_dma_cb *control_block; -+ -+ /* allocate and setup the descriptor. */ -+ d = kzalloc(sizeof(*d) + frames * sizeof(struct bcm2835_cb_entry), -+ gfp); -+ if (!d) -+ return NULL; -+ -+ d->c = c; -+ d->dir = direction; -+ d->cyclic = cyclic; -+ -+ /* -+ * Iterate over all frames, create a control block -+ * for each frame and link them together. -+ */ -+ for (frame = 0, total_len = 0; frame < frames; d->frames++, frame++) { -+ cb_entry = &d->cb_list[frame]; -+ cb_entry->cb = dma_pool_alloc(c->cb_pool, gfp, -+ &cb_entry->paddr); -+ if (!cb_entry->cb) -+ goto error_cb; -+ -+ /* fill in the control block */ -+ control_block = cb_entry->cb; -+ control_block->info = info; -+ control_block->src = src; -+ control_block->dst = dst; -+ control_block->stride = 0; -+ control_block->next = 0; -+ /* set up length in control_block if requested */ -+ if (buf_len) { -+ /* calculate length honoring period_length */ -+ bcm2835_dma_create_cb_set_length( -+ c, control_block, -+ len, period_len, &total_len, -+ cyclic ? finalextrainfo : 0); -+ -+ /* calculate new remaining length */ -+ len -= control_block->length; -+ } -+ -+ /* link this the last controlblock */ -+ if (frame) -+ d->cb_list[frame - 1].cb->next = cb_entry->paddr; -+ -+ /* update src and dst and length */ -+ if (src && (info & BCM2835_DMA_S_INC)) -+ src += control_block->length; -+ if (dst && (info & BCM2835_DMA_D_INC)) -+ dst += control_block->length; -+ -+ /* Length of total transfer */ -+ d->size += control_block->length; -+ } -+ -+ /* the last frame requires extra flags */ -+ d->cb_list[d->frames - 1].cb->info |= finalextrainfo; -+ -+ /* detect a size missmatch */ -+ if (buf_len && (d->size != buf_len)) -+ goto error_cb; -+ -+ return d; -+error_cb: -+ bcm2835_dma_free_cb_chain(d); -+ -+ return NULL; -+} -+ - static int bcm2835_dma_abort(void __iomem *chan_base) - { - unsigned long cs; -@@ -391,12 +540,11 @@ static struct dma_async_tx_descriptor *b - unsigned long flags) - { - struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); -- enum dma_slave_buswidth dev_width; - struct bcm2835_desc *d; -- dma_addr_t dev_addr; -- unsigned int es, sync_type; -- unsigned int frame; -- int i; -+ dma_addr_t src, dst; -+ u32 info = BCM2835_DMA_WAIT_RESP; -+ u32 extra = BCM2835_DMA_INT_EN; -+ size_t frames; - - /* Grab configuration */ - if (!is_slave_direction(direction)) { -@@ -404,104 +552,58 @@ static struct dma_async_tx_descriptor *b - return NULL; - } - -- if (direction == DMA_DEV_TO_MEM) { -- dev_addr = c->cfg.src_addr; -- dev_width = c->cfg.src_addr_width; -- sync_type = BCM2835_DMA_S_DREQ; -- } else { -- dev_addr = c->cfg.dst_addr; -- dev_width = c->cfg.dst_addr_width; -- sync_type = BCM2835_DMA_D_DREQ; -- } -- -- /* Bus width translates to the element size (ES) */ -- switch (dev_width) { -- case DMA_SLAVE_BUSWIDTH_4_BYTES: -- es = BCM2835_DMA_DATA_TYPE_S32; -- break; -- default: -+ if (!buf_len) { -+ dev_err(chan->device->dev, -+ "%s: bad buffer length (= 0)\n", __func__); - return NULL; - } - -- /* Now allocate and setup the descriptor. */ -- d = kzalloc(sizeof(*d), GFP_NOWAIT); -- if (!d) -- return NULL; -- -- d->c = c; -- d->dir = direction; -- d->frames = buf_len / period_len; -- d->cyclic = true; -+ /* -+ * warn if buf_len is not a multiple of period_len - this may leed -+ * to unexpected latencies for interrupts and thus audiable clicks -+ */ -+ if (buf_len % period_len) -+ dev_warn_once(chan->device->dev, -+ "%s: buffer_length (%zd) is not a multiple of period_len (%zd)\n", -+ __func__, buf_len, period_len); -+ -+ /* Setup DREQ channel */ -+ if (c->dreq != 0) -+ info |= BCM2835_DMA_PER_MAP(c->dreq); - -- d->cb_list = kcalloc(d->frames, sizeof(*d->cb_list), GFP_KERNEL); -- if (!d->cb_list) { -- kfree(d); -- return NULL; -+ if (direction == DMA_DEV_TO_MEM) { -+ if (c->cfg.src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) -+ return NULL; -+ src = c->cfg.src_addr; -+ dst = buf_addr; -+ info |= BCM2835_DMA_S_DREQ | BCM2835_DMA_D_INC; -+ } else { -+ if (c->cfg.dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) -+ return NULL; -+ dst = c->cfg.dst_addr; -+ src = buf_addr; -+ info |= BCM2835_DMA_D_DREQ | BCM2835_DMA_S_INC; - } -- /* Allocate memory for control blocks */ -- for (i = 0; i < d->frames; i++) { -- struct bcm2835_cb_entry *cb_entry = &d->cb_list[i]; - -- cb_entry->cb = dma_pool_zalloc(c->cb_pool, GFP_ATOMIC, -- &cb_entry->paddr); -- if (!cb_entry->cb) -- goto error_cb; -- } -+ /* calculate number of frames */ -+ frames = DIV_ROUND_UP(buf_len, period_len); - - /* -- * Iterate over all frames, create a control block -- * for each frame and link them together. -+ * allocate the CB chain -+ * note that we need to use GFP_NOWAIT, as the ALSA i2s dmaengine -+ * implementation calls prep_dma_cyclic with interrupts disabled. - */ -- for (frame = 0; frame < d->frames; frame++) { -- struct bcm2835_dma_cb *control_block = d->cb_list[frame].cb; -- -- /* Setup adresses */ -- if (d->dir == DMA_DEV_TO_MEM) { -- control_block->info = BCM2835_DMA_D_INC; -- control_block->src = dev_addr; -- control_block->dst = buf_addr + frame * period_len; -- } else { -- control_block->info = BCM2835_DMA_S_INC; -- control_block->src = buf_addr + frame * period_len; -- control_block->dst = dev_addr; -- } -- -- /* Enable interrupt */ -- control_block->info |= BCM2835_DMA_INT_EN; -- -- /* Setup synchronization */ -- if (sync_type != 0) -- control_block->info |= sync_type; -- -- /* Setup DREQ channel */ -- if (c->dreq != 0) -- control_block->info |= -- BCM2835_DMA_PER_MAP(c->dreq); -- -- /* Length of a frame */ -- control_block->length = period_len; -- d->size += control_block->length; -+ d = bcm2835_dma_create_cb_chain(chan, direction, true, -+ info, extra, -+ frames, src, dst, buf_len, -+ period_len, GFP_NOWAIT); -+ if (!d) -+ return NULL; - -- /* -- * Next block is the next frame. -- * This DMA engine driver currently only supports cyclic DMA. -- * Therefore, wrap around at number of frames. -- */ -- control_block->next = d->cb_list[((frame + 1) % d->frames)].paddr; -- } -+ /* wrap around into a loop */ -+ d->cb_list[d->frames - 1].cb->next = d->cb_list[0].paddr; - - return vchan_tx_prep(&c->vc, &d->vd, flags); --error_cb: -- i--; -- for (; i >= 0; i--) { -- struct bcm2835_cb_entry *cb_entry = &d->cb_list[i]; -- -- dma_pool_free(c->cb_pool, cb_entry->cb, cb_entry->paddr); -- } -- -- kfree(d->cb_list); -- kfree(d); -- return NULL; - } - - static int bcm2835_dma_slave_config(struct dma_chan *chan, |