Cleanups and improvenments for pl330

Cleanups and improvenments for pl330

[Alexander Kochetkov]

The patch series of 4 patches contain some pl330 driver cleanups and
implement free running mode for cyclic transfers. It affect recent
patches for pl330. Please review it and check on real boards (if possible).

Rebased on top of branch 'topic/pl330' of
https://git.kernel.org/cgit/linux/kernel/git/vkoul/slave-dma.git/

Tested on rk3188 Radxa rock board.

[PATCH 1/4] dmaengine: pl330: cleanup quirk pass code

[Alexander Kochetkov]

The patch add 'quirk' member to 'struct _xfer_spec' and
remove 'struct pl330_dmac *pl330' parameter from
many intermediate functions.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
---
 drivers/dma/pl330.c |   59 ++++++++++++++++++++++++---------------------------
 1 file changed, 28 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 1b0453b..7a17c0f 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -534,6 +534,7 @@ struct dma_pl330_desc {
 struct _xfer_spec {
 	u32 ccr;
 	struct dma_pl330_desc *desc;
+	int quirks;
 };
 
 static inline bool _queue_empty(struct pl330_thread *thrd)
@@ -1151,14 +1152,13 @@ static inline int _ldst_memtomem(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
-				 u8 buf[], const struct _xfer_spec *pxs,
-				 int cyc)
+static inline int _ldst_devtomem(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = (pxs->desc->rqcfg.brst_len == 1) ? SINGLE : BURST;
@@ -1168,7 +1168,7 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 		off += _emit_LDP(dry_run, &buf[off], cond, pxs->desc->peri);
 		off += _emit_ST(dry_run, &buf[off], ALWAYS);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1176,14 +1176,13 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 	return off;
 }
 
-static inline int _ldst_memtodev(struct pl330_dmac *pl330,
-				 unsigned dry_run, u8 buf[],
-				 const struct _xfer_spec *pxs, int cyc)
+static inline int _ldst_memtodev(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = (pxs->desc->rqcfg.brst_len == 1) ? SINGLE : BURST;
@@ -1194,7 +1193,7 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 		off += _emit_LD(dry_run, &buf[off], ALWAYS);
 		off += _emit_STP(dry_run, &buf[off], cond, pxs->desc->peri);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1202,17 +1201,17 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 	return off;
 }
 
-static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static int _bursts(unsigned dry_run, u8 buf[],
 		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 
 	switch (pxs->desc->rqtype) {
 	case DMA_MEM_TO_DEV:
-		off += _ldst_memtodev(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_memtodev(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_DEV_TO_MEM:
-		off += _ldst_devtomem(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_devtomem(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_MEM_TO_MEM:
 		off += _ldst_memtomem(dry_run, &buf[off], pxs, cyc);
@@ -1226,7 +1225,7 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 }
 
 /* Returns bytes consumed and updates bursts */
-static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static inline int _loop(unsigned dry_run, u8 buf[],
 		unsigned long *bursts, const struct _xfer_spec *pxs)
 {
 	int cyc, cycmax, szlp, szlpend, szbrst, off;
@@ -1234,7 +1233,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	struct _arg_LPEND lpend;
 
 	if (*bursts == 1)
-		return _bursts(pl330, dry_run, buf, pxs, 1);
+		return _bursts(dry_run, buf, pxs, 1);
 
 	/* Max iterations possible in DMALP is 256 */
 	if (*bursts >= 256*256) {
@@ -1252,7 +1251,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	}
 
 	szlp = _emit_LP(1, buf, 0, 0);
-	szbrst = _bursts(pl330, 1, buf, pxs, 1);
+	szbrst = _bursts(1, buf, pxs, 1);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1284,7 +1283,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	off += _emit_LP(dry_run, &buf[off], 1, lcnt1);
 	ljmp1 = off;
 
-	off += _bursts(pl330, dry_run, &buf[off], pxs, cyc);
+	off += _bursts(dry_run, &buf[off], pxs, cyc);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1307,9 +1306,8 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_loops(struct pl330_dmac *pl330,
-			       unsigned dry_run, u8 buf[],
-			       const struct _xfer_spec *pxs)
+static inline int _setup_loops(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	u32 ccr = pxs->ccr;
@@ -1318,16 +1316,15 @@ static inline int _setup_loops(struct pl330_dmac *pl330,
 
 	while (bursts) {
 		c = bursts;
-		off += _loop(pl330, dry_run, &buf[off], &c, pxs);
+		off += _loop(dry_run, &buf[off], &c, pxs);
 		bursts -= c;
 	}
 
 	return off;
 }
 
-static inline int _setup_xfer(struct pl330_dmac *pl330,
-			      unsigned dry_run, u8 buf[],
-			      const struct _xfer_spec *pxs)
+static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	int off = 0;
@@ -1338,7 +1335,7 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
 	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
 
 	/* Setup Loop(s) */
-	off += _setup_loops(pl330, dry_run, &buf[off], pxs);
+	off += _setup_loops(dry_run, &buf[off], pxs);
 
 	return off;
 }
@@ -1347,9 +1344,8 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
  * A req is a sequence of one or more xfer units.
  * Returns the number of bytes taken to setup the MC for the req.
  */
-static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
-		      struct pl330_thread *thrd, unsigned index,
-		      struct _xfer_spec *pxs)
+static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
+		unsigned index, struct _xfer_spec *pxs)
 {
 	struct _pl330_req *req = &thrd->req[index];
 	struct pl330_xfer *x;
@@ -1366,7 +1362,7 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(pl330, dry_run, &buf[off], pxs);
+	off += _setup_xfer(dry_run, &buf[off], pxs);
 
 	/* DMASEV peripheral/event */
 	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
@@ -1458,9 +1454,10 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 
 	xs.ccr = ccr;
 	xs.desc = desc;
+	xs.quirks = pl330->quirks;
 
 	/* First dry run to check if req is acceptable */
-	ret = _setup_req(pl330, 1, thrd, idx, &xs);
+	ret = _setup_req(1, thrd, idx, &xs);
 	if (ret < 0)
 		goto xfer_exit;
 
@@ -1474,7 +1471,7 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 	/* Hook the request */
 	thrd->lstenq = idx;
 	thrd->req[idx].desc = desc;
-	_setup_req(pl330, 0, thrd, idx, &xs);
+	_setup_req(0, thrd, idx, &xs);
 
 	ret = 0;
 
-- 
1.7.9.5

[PATCH 2/4] dmaengine: pl330: cleanup brst_len usage

[Alexander Kochetkov]

brst_len can be extracted from ccr register
in ldst_devtomem() and ldst_memtodev().

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
---
 drivers/dma/pl330.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 7a17c0f..9ce6c10 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1161,7 +1161,7 @@ static inline int _ldst_devtomem(unsigned dry_run, u8 buf[],
 	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
-		cond = (pxs->desc->rqcfg.brst_len == 1) ? SINGLE : BURST;
+		cond = (BRST_LEN(pxs->ccr) == 1) ? SINGLE : BURST;
 
 	while (cyc--) {
 		off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri);
@@ -1185,8 +1185,7 @@ static inline int _ldst_memtodev(unsigned dry_run, u8 buf[],
 	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
-		cond = (pxs->desc->rqcfg.brst_len == 1) ? SINGLE : BURST;
-
+		cond = (BRST_LEN(pxs->ccr) == 1) ? SINGLE : BURST;
 
 	while (cyc--) {
 		off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri);
-- 
1.7.9.5

[PATCH 3/4] dmaengine: pl330: don't emit code for one iteration loop

[Alexander Kochetkov]

The patch remove one iteration outer loop in the _loop().

    DMALP_0 0
    ...
    DMALPENDA_0 bjmpto_9

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
---
 drivers/dma/pl330.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 9ce6c10..711ea58 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1258,7 +1258,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = 0;
 	szlpend = _emit_LPEND(1, buf, &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		szlp *= 2;
 		szlpend *= 2;
 	}
@@ -1274,7 +1274,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 
 	off = 0;
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		off += _emit_LP(dry_run, &buf[off], 0, lcnt0);
 		ljmp0 = off;
 	}
@@ -1290,7 +1290,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = off - ljmp1;
 	off += _emit_LPEND(dry_run, &buf[off], &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		lpend.cond = ALWAYS;
 		lpend.forever = false;
 		lpend.loop = 0;
@@ -1299,7 +1299,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	}
 
 	*bursts = lcnt1 * cyc;
-	if (lcnt0)
+	if (lcnt0 > 1)
 		*bursts *= lcnt0;
 
 	return off;
-- 
1.7.9.5

[PATCH 4/4] dmaengine: pl330: make cyclic transfer free runnable

[Alexander Kochetkov]

Current implemantation depends on soft irq. If pl330 unable
to submit next transfer in time some samples could be lost.
In order to check this, I've installed I2S interrupt handler
to signal overflow/underflow conditions. Sometimes samples
get lost.

The patch setup setup cyclic transfer such a way, that transfer
can run infinitely without CPU intervention. As a result, lost
samples gone.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
---
 drivers/dma/pl330.c |  190 +++++++++++++++++++++++++--------------------------
 1 file changed, 93 insertions(+), 97 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 711ea58..1ce48ab 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -445,9 +445,6 @@ struct dma_pl330_chan {
 	int burst_sz; /* the peripheral fifo width */
 	int burst_len; /* the number of burst */
 	dma_addr_t fifo_addr;
-
-	/* for cyclic capability */
-	bool cyclic;
 };
 
 struct pl330_dmac {
@@ -529,6 +526,10 @@ struct dma_pl330_desc {
 	unsigned peri:5;
 	/* Hook to attach to DMAC's list of reqs with due callback */
 	struct list_head rqd;
+
+	/* For cyclic capability */
+	bool cyclic;
+	size_t num_periods;
 };
 
 struct _xfer_spec {
@@ -1322,16 +1323,19 @@ static inline int _setup_loops(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+static inline int _setup_xfer(unsigned dry_run, u8 buf[], u32 period,
 		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
+	struct pl330_reqcfg *rqcfg = &pxs->desc->rqcfg;
 	int off = 0;
 
 	/* DMAMOV SAR, x->src_addr */
-	off += _emit_MOV(dry_run, &buf[off], SAR, x->src_addr);
+	off += _emit_MOV(dry_run, &buf[off], SAR,
+		x->src_addr + rqcfg->src_inc * period * x->bytes);
 	/* DMAMOV DAR, x->dst_addr */
-	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
+	off += _emit_MOV(dry_run, &buf[off], DAR,
+		x->dst_addr + rqcfg->dst_inc * period * x->bytes);
 
 	/* Setup Loop(s) */
 	off += _setup_loops(dry_run, &buf[off], pxs);
@@ -1350,23 +1354,41 @@ static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
 	struct pl330_xfer *x;
 	u8 *buf = req->mc_cpu;
 	int off = 0;
+	int period;
+	int again_off;
 
 	PL330_DBGMC_START(req->mc_bus);
 
 	/* DMAMOV CCR, ccr */
 	off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr);
+	again_off = off;
 
 	x = &pxs->desc->px;
 	/* Error if xfer length is not aligned at burst size */
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(dry_run, &buf[off], pxs);
+	for (period = 0; period < pxs->desc->num_periods; period++) {
+		off += _setup_xfer(dry_run, &buf[off], period, pxs);
 
-	/* DMASEV peripheral/event */
-	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
-	/* DMAEND */
-	off += _emit_END(dry_run, &buf[off]);
+		/* DMASEV peripheral/event */
+		off += _emit_SEV(dry_run, &buf[off], thrd->ev);
+	}
+
+	if (!pxs->desc->cyclic) {
+		/* DMAEND */
+		off += _emit_END(dry_run, &buf[off]);
+	} else {
+		struct _arg_LPEND lpend;
+		/* LP */
+		off += _emit_LP(dry_run, &buf[off], 0, 255);
+		/* LPEND */
+		lpend.cond = ALWAYS;
+		lpend.forever = false;
+		lpend.loop = 0;
+		lpend.bjump = off - again_off;
+		off += _emit_LPEND(dry_run, &buf[off], &lpend);
+	}
 
 	return off;
 }
@@ -1629,12 +1651,13 @@ static int pl330_update(struct pl330_dmac *pl330)
 
 			/* Detach the req */
 			descdone = thrd->req[active].desc;
-			thrd->req[active].desc = NULL;
-
-			thrd->req_running = -1;
 
-			/* Get going again ASAP */
-			_start(thrd);
+			if (!descdone->cyclic) {
+				thrd->req[active].desc = NULL;
+				thrd->req_running = -1;
+				/* Get going again ASAP */
+				_start(thrd);
+			}
 
 			/* For now, just make a list of callbacks to be done */
 			list_add_tail(&descdone->rqd, &pl330->req_done);
@@ -2013,12 +2036,27 @@ static void pl330_tasklet(unsigned long data)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Pick up ripe tomatoes */
-	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
+	list_for_each_entry_safe(desc, _dt, &pch->work_list, node) {
 		if (desc->status == DONE) {
-			if (!pch->cyclic)
+			if (!desc->cyclic) {
 				dma_cookie_complete(&desc->txd);
-			list_move_tail(&desc->node, &pch->completed_list);
+				list_move_tail(&desc->node, &pch->completed_list);
+			} else {
+				dma_async_tx_callback callback;
+				void *callback_param;
+
+				desc->status = BUSY;
+				callback = desc->txd.callback;
+				callback_param = desc->txd.callback_param;
+
+				if (callback) {
+					spin_unlock_irqrestore(&pch->lock, flags);
+					callback(callback_param);
+					spin_lock_irqsave(&pch->lock, flags);
+				}
+			}
 		}
+	}
 
 	/* Try to submit a req imm. next to the last completed cookie */
 	fill_queue(pch);
@@ -2045,19 +2083,8 @@ static void pl330_tasklet(unsigned long data)
 		callback = desc->txd.callback;
 		callback_param = desc->txd.callback_param;
 
-		if (pch->cyclic) {
-			desc->status = PREP;
-			list_move_tail(&desc->node, &pch->work_list);
-			if (power_down) {
-				spin_lock(&pch->thread->dmac->lock);
-				_start(pch->thread);
-				spin_unlock(&pch->thread->dmac->lock);
-				power_down = false;
-			}
-		} else {
-			desc->status = FREE;
-			list_move_tail(&desc->node, &pch->dmac->desc_pool);
-		}
+		desc->status = FREE;
+		list_move_tail(&desc->node, &pch->dmac->desc_pool);
 
 		dma_descriptor_unmap(&desc->txd);
 
@@ -2117,7 +2144,6 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	dma_cookie_init(chan);
-	pch->cyclic = false;
 
 	pch->thread = pl330_request_channel(pl330);
 	if (!pch->thread) {
@@ -2235,8 +2261,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
 	pl330_release_channel(pch->thread);
 	pch->thread = NULL;
 
-	if (pch->cyclic)
-		list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
+	list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
 
 	spin_unlock_irqrestore(&pch->lock, flags);
 	pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
@@ -2290,7 +2315,7 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 
 	/* Check in pending list */
 	list_for_each_entry(desc, &pch->work_list, node) {
-		if (desc->status == DONE)
+		if (desc->status == DONE && !desc->cyclic)
 			transferred = desc->bytes_requested;
 		else if (running && desc == running)
 			transferred =
@@ -2361,12 +2386,8 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	/* Assign cookies to all nodes */
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
-		if (pch->cyclic) {
-			desc->txd.callback = last->txd.callback;
-			desc->txd.callback_param = last->txd.callback_param;
-		}
-		desc->last = false;
 
+		desc->last = false;
 		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->submitted_list);
@@ -2466,6 +2487,9 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->peri = peri_id ? pch->chan.chan_id : 0;
 	desc->rqcfg.pcfg = &pch->dmac->pcfg;
 
+	desc->cyclic = false;
+	desc->num_periods = 1;
+
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
 	return desc;
@@ -2535,10 +2559,8 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		size_t period_len, enum dma_transfer_direction direction,
 		unsigned long flags)
 {
-	struct dma_pl330_desc *desc = NULL, *first = NULL;
+	struct dma_pl330_desc *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct pl330_dmac *pl330 = pch->dmac;
-	unsigned int i;
 	dma_addr_t dst;
 	dma_addr_t src;
 
@@ -2551,65 +2573,39 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		return NULL;
 	}
 
-	for (i = 0; i < len / period_len; i++) {
-		desc = pl330_get_desc(pch);
-		if (!desc) {
-			dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
-				__func__, __LINE__);
-
-			if (!first)
-				return NULL;
-
-			spin_lock_irqsave(&pl330->pool_lock, flags);
-
-			while (!list_empty(&first->node)) {
-				desc = list_entry(first->node.next,
-						struct dma_pl330_desc, node);
-				list_move_tail(&desc->node, &pl330->desc_pool);
-			}
-
-			list_move_tail(&first->node, &pl330->desc_pool);
-
-			spin_unlock_irqrestore(&pl330->pool_lock, flags);
+	desc = pl330_get_desc(pch);
+	if (!desc) {
+		dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
+			__func__, __LINE__);
 
 			return NULL;
-		}
-
-		switch (direction) {
-		case DMA_MEM_TO_DEV:
-			desc->rqcfg.src_inc = 1;
-			desc->rqcfg.dst_inc = 0;
-			src = dma_addr;
-			dst = pch->fifo_addr;
-			break;
-		case DMA_DEV_TO_MEM:
-			desc->rqcfg.src_inc = 0;
-			desc->rqcfg.dst_inc = 1;
-			src = pch->fifo_addr;
-			dst = dma_addr;
-			break;
-		default:
-			break;
-		}
-
-		desc->rqtype = direction;
-		desc->rqcfg.brst_size = pch->burst_sz;
-		desc->rqcfg.brst_len = pch->burst_len;
-		desc->bytes_requested = period_len;
-		fill_px(&desc->px, dst, src, period_len);
-
-		if (!first)
-			first = desc;
-		else
-			list_add_tail(&desc->node, &first->node);
+	}
 
-		dma_addr += period_len;
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		desc->rqcfg.src_inc = 1;
+		desc->rqcfg.dst_inc = 0;
+		src = dma_addr;
+		dst = pch->fifo_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		desc->rqcfg.src_inc = 0;
+		desc->rqcfg.dst_inc = 1;
+		src = pch->fifo_addr;
+		dst = dma_addr;
+		break;
+	default:
+		break;
 	}
 
-	if (!desc)
-		return NULL;
+	desc->rqtype = direction;
+	desc->rqcfg.brst_size = pch->burst_sz;
+	desc->rqcfg.brst_len = pch->burst_len;
+	desc->bytes_requested = len;
+	fill_px(&desc->px, dst, src, period_len);
 
-	pch->cyclic = true;
+	desc->cyclic = true;
+	desc->num_periods = len / period_len;
 	desc->txd.flags = flags;
 
 	return &desc->txd;
-- 
1.7.9.5

Re: Cleanups and improvenments for pl330

[Vinod Koul]

On Thu, Feb 18, 2016 at 03:31:10PM +0300, Alexander Kochetkov wrote:
> The patch series of 4 patches contain some pl330 driver cleanups and
> implement free running mode for cyclic transfers. It affect recent
> patches for pl330. Please review it and check on real boards (if possible).
> 
> Rebased on top of branch 'topic/pl330' of
> https://git.kernel.org/cgit/linux/kernel/git/vkoul/slave-dma.git/
> 
> Tested on rk3188 Radxa rock board.

Overall this series looks okay, but can someone test this. I would not like
pl330 to be roken again
> 
> --
> To unsubscribe from this list: send the line "unsubscribe dmaengine" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
~Vinod

[PATCH 1/3 v2] dmaengine: pl330: cleanup quirk pass code

[Alexander Kochetkov]

The patch partially revert changes introduced by 271e1b86e691
"dmaengine: pl330: add quirk for broken no flushp"

The patch add 'quirk' member to 'struct _xfer_spec' and
remove 'struct pl330_dmac *pl330' parameter from
many intermediate functions. The patch is intended to
hide 'struct pl330_dmac' implementation from Microcode
generation functions.

The patch is here to allow easy backporting following
patches to longterm linux 4.1.x.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |   59 ++++++++++++++++++++++++---------------------------
 1 file changed, 28 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 372b435..4abbc71 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -534,6 +534,7 @@ struct dma_pl330_desc {
 struct _xfer_spec {
 	u32 ccr;
 	struct dma_pl330_desc *desc;
+	int quirks;
 };
 
 static inline bool _queue_empty(struct pl330_thread *thrd)
@@ -1151,14 +1152,13 @@ static inline int _ldst_memtomem(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
-				 u8 buf[], const struct _xfer_spec *pxs,
-				 int cyc)
+static inline int _ldst_devtomem(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1168,7 +1168,7 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 		off += _emit_LDP(dry_run, &buf[off], cond, pxs->desc->peri);
 		off += _emit_ST(dry_run, &buf[off], ALWAYS);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1176,14 +1176,13 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 	return off;
 }
 
-static inline int _ldst_memtodev(struct pl330_dmac *pl330,
-				 unsigned dry_run, u8 buf[],
-				 const struct _xfer_spec *pxs, int cyc)
+static inline int _ldst_memtodev(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1193,7 +1192,7 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 		off += _emit_LD(dry_run, &buf[off], ALWAYS);
 		off += _emit_STP(dry_run, &buf[off], cond, pxs->desc->peri);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1201,17 +1200,17 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 	return off;
 }
 
-static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static int _bursts(unsigned dry_run, u8 buf[],
 		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 
 	switch (pxs->desc->rqtype) {
 	case DMA_MEM_TO_DEV:
-		off += _ldst_memtodev(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_memtodev(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_DEV_TO_MEM:
-		off += _ldst_devtomem(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_devtomem(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_MEM_TO_MEM:
 		off += _ldst_memtomem(dry_run, &buf[off], pxs, cyc);
@@ -1225,7 +1224,7 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 }
 
 /* Returns bytes consumed and updates bursts */
-static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static inline int _loop(unsigned dry_run, u8 buf[],
 		unsigned long *bursts, const struct _xfer_spec *pxs)
 {
 	int cyc, cycmax, szlp, szlpend, szbrst, off;
@@ -1233,7 +1232,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	struct _arg_LPEND lpend;
 
 	if (*bursts == 1)
-		return _bursts(pl330, dry_run, buf, pxs, 1);
+		return _bursts(dry_run, buf, pxs, 1);
 
 	/* Max iterations possible in DMALP is 256 */
 	if (*bursts >= 256*256) {
@@ -1251,7 +1250,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	}
 
 	szlp = _emit_LP(1, buf, 0, 0);
-	szbrst = _bursts(pl330, 1, buf, pxs, 1);
+	szbrst = _bursts(1, buf, pxs, 1);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1283,7 +1282,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	off += _emit_LP(dry_run, &buf[off], 1, lcnt1);
 	ljmp1 = off;
 
-	off += _bursts(pl330, dry_run, &buf[off], pxs, cyc);
+	off += _bursts(dry_run, &buf[off], pxs, cyc);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1306,9 +1305,8 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_loops(struct pl330_dmac *pl330,
-			       unsigned dry_run, u8 buf[],
-			       const struct _xfer_spec *pxs)
+static inline int _setup_loops(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	u32 ccr = pxs->ccr;
@@ -1317,16 +1315,15 @@ static inline int _setup_loops(struct pl330_dmac *pl330,
 
 	while (bursts) {
 		c = bursts;
-		off += _loop(pl330, dry_run, &buf[off], &c, pxs);
+		off += _loop(dry_run, &buf[off], &c, pxs);
 		bursts -= c;
 	}
 
 	return off;
 }
 
-static inline int _setup_xfer(struct pl330_dmac *pl330,
-			      unsigned dry_run, u8 buf[],
-			      const struct _xfer_spec *pxs)
+static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	int off = 0;
@@ -1337,7 +1334,7 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
 	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
 
 	/* Setup Loop(s) */
-	off += _setup_loops(pl330, dry_run, &buf[off], pxs);
+	off += _setup_loops(dry_run, &buf[off], pxs);
 
 	return off;
 }
@@ -1346,9 +1343,8 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
  * A req is a sequence of one or more xfer units.
  * Returns the number of bytes taken to setup the MC for the req.
  */
-static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
-		      struct pl330_thread *thrd, unsigned index,
-		      struct _xfer_spec *pxs)
+static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
+		unsigned index, struct _xfer_spec *pxs)
 {
 	struct _pl330_req *req = &thrd->req[index];
 	struct pl330_xfer *x;
@@ -1365,7 +1361,7 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(pl330, dry_run, &buf[off], pxs);
+	off += _setup_xfer(dry_run, &buf[off], pxs);
 
 	/* DMASEV peripheral/event */
 	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
@@ -1457,9 +1453,10 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 
 	xs.ccr = ccr;
 	xs.desc = desc;
+	xs.quirks = pl330->quirks;
 
 	/* First dry run to check if req is acceptable */
-	ret = _setup_req(pl330, 1, thrd, idx, &xs);
+	ret = _setup_req(1, thrd, idx, &xs);
 	if (ret < 0)
 		goto xfer_exit;
 
@@ -1473,7 +1470,7 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 	/* Hook the request */
 	thrd->lstenq = idx;
 	thrd->req[idx].desc = desc;
-	_setup_req(pl330, 0, thrd, idx, &xs);
+	_setup_req(0, thrd, idx, &xs);
 
 	ret = 0;
 
-- 
1.7.9.5

[PATCH 2/3 v2] dmaengine: pl330: don't emit code for one iteration loop

[Alexander Kochetkov]

The patch remove one iteration outer loop in the _loop().
Removing loop saves 4 bytes of MicroCode buffer.

    DMALP_0 0
    ...
    DMALPENDA_0 bjmpto_9

Signed-off-by: Alexander Kochetkov <al.kochet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Caesar Wang <wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/dma/pl330.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 4abbc71..b080d70 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1258,7 +1258,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = 0;
 	szlpend = _emit_LPEND(1, buf, &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		szlp *= 2;
 		szlpend *= 2;
 	}
@@ -1274,7 +1274,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 
 	off = 0;
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		off += _emit_LP(dry_run, &buf[off], 0, lcnt0);
 		ljmp0 = off;
 	}
@@ -1290,7 +1290,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = off - ljmp1;
 	off += _emit_LPEND(dry_run, &buf[off], &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		lpend.cond = ALWAYS;
 		lpend.forever = false;
 		lpend.loop = 0;
@@ -1299,7 +1299,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	}
 
 	*bursts = lcnt1 * cyc;
-	if (lcnt0)
+	if (lcnt0 > 1)
 		*bursts *= lcnt0;
 
 	return off;
-- 
1.7.9.5

[PATCH 2/3 v2] dmaengine: pl330: don't emit code for one iteration loop

[Alexander Kochetkov]

The patch remove one iteration outer loop in the _loop().
Removing loop saves 4 bytes of MicroCode buffer.

    DMALP_0 0
    ...
    DMALPENDA_0 bjmpto_9

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 4abbc71..b080d70 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1258,7 +1258,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = 0;
 	szlpend = _emit_LPEND(1, buf, &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		szlp *= 2;
 		szlpend *= 2;
 	}
@@ -1274,7 +1274,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 
 	off = 0;
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		off += _emit_LP(dry_run, &buf[off], 0, lcnt0);
 		ljmp0 = off;
 	}
@@ -1290,7 +1290,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = off - ljmp1;
 	off += _emit_LPEND(dry_run, &buf[off], &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		lpend.cond = ALWAYS;
 		lpend.forever = false;
 		lpend.loop = 0;
@@ -1299,7 +1299,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	}
 
 	*bursts = lcnt1 * cyc;
-	if (lcnt0)
+	if (lcnt0 > 1)
 		*bursts *= lcnt0;
 
 	return off;
-- 
1.7.9.5

[PATCH 3/3 v2] dmaengine: pl330: make cyclic transfer free runnable

[Alexander Kochetkov]

The patch solve the I2S click problem on rk3188. Actually
all the devices using pl330 should have I2S click problem
due to pl330 cyclic transfer implementation.

Current implemantation depends on soft irq. If pl330 unable
to submit next transfer in time some samples could be lost.
The lost samples heared as sound click. In order to check
lost samples, I've installed I2S interrupt handler to signal
overflow/underflow conditions. Sometimes I saw overflow
or underflow events and heard clicks.

The patch setup cyclic transfer such a way, that transfer can
run infinitely without CPU intervention. As a result,
lost samples and clicks gone.

Signed-off-by: Alexander Kochetkov <al.kochet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Caesar Wang <wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/dma/pl330.c |  190 +++++++++++++++++++++++++--------------------------
 1 file changed, 93 insertions(+), 97 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index b080d70..a07f0c9 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -445,9 +445,6 @@ struct dma_pl330_chan {
 	int burst_sz; /* the peripheral fifo width */
 	int burst_len; /* the number of burst */
 	dma_addr_t fifo_addr;
-
-	/* for cyclic capability */
-	bool cyclic;
 };
 
 struct pl330_dmac {
@@ -529,6 +526,10 @@ struct dma_pl330_desc {
 	unsigned peri:5;
 	/* Hook to attach to DMAC's list of reqs with due callback */
 	struct list_head rqd;
+
+	/* For cyclic capability */
+	bool cyclic;
+	size_t num_periods;
 };
 
 struct _xfer_spec {
@@ -1322,16 +1323,19 @@ static inline int _setup_loops(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+static inline int _setup_xfer(unsigned dry_run, u8 buf[], u32 period,
 		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
+	struct pl330_reqcfg *rqcfg = &pxs->desc->rqcfg;
 	int off = 0;
 
 	/* DMAMOV SAR, x->src_addr */
-	off += _emit_MOV(dry_run, &buf[off], SAR, x->src_addr);
+	off += _emit_MOV(dry_run, &buf[off], SAR,
+		x->src_addr + rqcfg->src_inc * period * x->bytes);
 	/* DMAMOV DAR, x->dst_addr */
-	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
+	off += _emit_MOV(dry_run, &buf[off], DAR,
+		x->dst_addr + rqcfg->dst_inc * period * x->bytes);
 
 	/* Setup Loop(s) */
 	off += _setup_loops(dry_run, &buf[off], pxs);
@@ -1350,23 +1354,41 @@ static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
 	struct pl330_xfer *x;
 	u8 *buf = req->mc_cpu;
 	int off = 0;
+	int period;
+	int again_off;
 
 	PL330_DBGMC_START(req->mc_bus);
 
 	/* DMAMOV CCR, ccr */
 	off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr);
+	again_off = off;
 
 	x = &pxs->desc->px;
 	/* Error if xfer length is not aligned at burst size */
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(dry_run, &buf[off], pxs);
+	for (period = 0; period < pxs->desc->num_periods; period++) {
+		off += _setup_xfer(dry_run, &buf[off], period, pxs);
 
-	/* DMASEV peripheral/event */
-	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
-	/* DMAEND */
-	off += _emit_END(dry_run, &buf[off]);
+		/* DMASEV peripheral/event */
+		off += _emit_SEV(dry_run, &buf[off], thrd->ev);
+	}
+
+	if (!pxs->desc->cyclic) {
+		/* DMAEND */
+		off += _emit_END(dry_run, &buf[off]);
+	} else {
+		struct _arg_LPEND lpend;
+		/* LP */
+		off += _emit_LP(dry_run, &buf[off], 0, 255);
+		/* LPEND */
+		lpend.cond = ALWAYS;
+		lpend.forever = false;
+		lpend.loop = 0;
+		lpend.bjump = off - again_off;
+		off += _emit_LPEND(dry_run, &buf[off], &lpend);
+	}
 
 	return off;
 }
@@ -1629,12 +1651,13 @@ static int pl330_update(struct pl330_dmac *pl330)
 
 			/* Detach the req */
 			descdone = thrd->req[active].desc;
-			thrd->req[active].desc = NULL;
-
-			thrd->req_running = -1;
 
-			/* Get going again ASAP */
-			_start(thrd);
+			if (!descdone->cyclic) {
+				thrd->req[active].desc = NULL;
+				thrd->req_running = -1;
+				/* Get going again ASAP */
+				_start(thrd);
+			}
 
 			/* For now, just make a list of callbacks to be done */
 			list_add_tail(&descdone->rqd, &pl330->req_done);
@@ -2013,12 +2036,27 @@ static void pl330_tasklet(unsigned long data)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Pick up ripe tomatoes */
-	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
+	list_for_each_entry_safe(desc, _dt, &pch->work_list, node) {
 		if (desc->status == DONE) {
-			if (!pch->cyclic)
+			if (!desc->cyclic) {
 				dma_cookie_complete(&desc->txd);
-			list_move_tail(&desc->node, &pch->completed_list);
+				list_move_tail(&desc->node, &pch->completed_list);
+			} else {
+				dma_async_tx_callback callback;
+				void *callback_param;
+
+				desc->status = BUSY;
+				callback = desc->txd.callback;
+				callback_param = desc->txd.callback_param;
+
+				if (callback) {
+					spin_unlock_irqrestore(&pch->lock, flags);
+					callback(callback_param);
+					spin_lock_irqsave(&pch->lock, flags);
+				}
+			}
 		}
+	}
 
 	/* Try to submit a req imm. next to the last completed cookie */
 	fill_queue(pch);
@@ -2045,19 +2083,8 @@ static void pl330_tasklet(unsigned long data)
 		callback = desc->txd.callback;
 		callback_param = desc->txd.callback_param;
 
-		if (pch->cyclic) {
-			desc->status = PREP;
-			list_move_tail(&desc->node, &pch->work_list);
-			if (power_down) {
-				spin_lock(&pch->thread->dmac->lock);
-				_start(pch->thread);
-				spin_unlock(&pch->thread->dmac->lock);
-				power_down = false;
-			}
-		} else {
-			desc->status = FREE;
-			list_move_tail(&desc->node, &pch->dmac->desc_pool);
-		}
+		desc->status = FREE;
+		list_move_tail(&desc->node, &pch->dmac->desc_pool);
 
 		dma_descriptor_unmap(&desc->txd);
 
@@ -2117,7 +2144,6 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	dma_cookie_init(chan);
-	pch->cyclic = false;
 
 	pch->thread = pl330_request_channel(pl330);
 	if (!pch->thread) {
@@ -2235,8 +2261,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
 	pl330_release_channel(pch->thread);
 	pch->thread = NULL;
 
-	if (pch->cyclic)
-		list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
+	list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
 
 	spin_unlock_irqrestore(&pch->lock, flags);
 	pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
@@ -2290,7 +2315,7 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 
 	/* Check in pending list */
 	list_for_each_entry(desc, &pch->work_list, node) {
-		if (desc->status == DONE)
+		if (desc->status == DONE && !desc->cyclic)
 			transferred = desc->bytes_requested;
 		else if (running && desc == running)
 			transferred =
@@ -2361,12 +2386,8 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	/* Assign cookies to all nodes */
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
-		if (pch->cyclic) {
-			desc->txd.callback = last->txd.callback;
-			desc->txd.callback_param = last->txd.callback_param;
-		}
-		desc->last = false;
 
+		desc->last = false;
 		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->submitted_list);
@@ -2466,6 +2487,9 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->peri = peri_id ? pch->chan.chan_id : 0;
 	desc->rqcfg.pcfg = &pch->dmac->pcfg;
 
+	desc->cyclic = false;
+	desc->num_periods = 1;
+
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
 	return desc;
@@ -2535,10 +2559,8 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		size_t period_len, enum dma_transfer_direction direction,
 		unsigned long flags)
 {
-	struct dma_pl330_desc *desc = NULL, *first = NULL;
+	struct dma_pl330_desc *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct pl330_dmac *pl330 = pch->dmac;
-	unsigned int i;
 	dma_addr_t dst;
 	dma_addr_t src;
 
@@ -2551,65 +2573,39 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		return NULL;
 	}
 
-	for (i = 0; i < len / period_len; i++) {
-		desc = pl330_get_desc(pch);
-		if (!desc) {
-			dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
-				__func__, __LINE__);
-
-			if (!first)
-				return NULL;
-
-			spin_lock_irqsave(&pl330->pool_lock, flags);
-
-			while (!list_empty(&first->node)) {
-				desc = list_entry(first->node.next,
-						struct dma_pl330_desc, node);
-				list_move_tail(&desc->node, &pl330->desc_pool);
-			}
-
-			list_move_tail(&first->node, &pl330->desc_pool);
-
-			spin_unlock_irqrestore(&pl330->pool_lock, flags);
+	desc = pl330_get_desc(pch);
+	if (!desc) {
+		dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
+			__func__, __LINE__);
 
 			return NULL;
-		}
-
-		switch (direction) {
-		case DMA_MEM_TO_DEV:
-			desc->rqcfg.src_inc = 1;
-			desc->rqcfg.dst_inc = 0;
-			src = dma_addr;
-			dst = pch->fifo_addr;
-			break;
-		case DMA_DEV_TO_MEM:
-			desc->rqcfg.src_inc = 0;
-			desc->rqcfg.dst_inc = 1;
-			src = pch->fifo_addr;
-			dst = dma_addr;
-			break;
-		default:
-			break;
-		}
-
-		desc->rqtype = direction;
-		desc->rqcfg.brst_size = pch->burst_sz;
-		desc->rqcfg.brst_len = 1;
-		desc->bytes_requested = period_len;
-		fill_px(&desc->px, dst, src, period_len);
-
-		if (!first)
-			first = desc;
-		else
-			list_add_tail(&desc->node, &first->node);
+	}
 
-		dma_addr += period_len;
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		desc->rqcfg.src_inc = 1;
+		desc->rqcfg.dst_inc = 0;
+		src = dma_addr;
+		dst = pch->fifo_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		desc->rqcfg.src_inc = 0;
+		desc->rqcfg.dst_inc = 1;
+		src = pch->fifo_addr;
+		dst = dma_addr;
+		break;
+	default:
+		break;
 	}
 
-	if (!desc)
-		return NULL;
+	desc->rqtype = direction;
+	desc->rqcfg.brst_size = pch->burst_sz;
+	desc->rqcfg.brst_len = 1;
+	desc->bytes_requested = len;
+	fill_px(&desc->px, dst, src, period_len);
 
-	pch->cyclic = true;
+	desc->cyclic = true;
+	desc->num_periods = len / period_len;
 	desc->txd.flags = flags;
 
 	return &desc->txd;
-- 
1.7.9.5

[PATCH 3/3 v2] dmaengine: pl330: make cyclic transfer free runnable

[Alexander Kochetkov]

The patch solve the I2S click problem on rk3188. Actually
all the devices using pl330 should have I2S click problem
due to pl330 cyclic transfer implementation.

Current implemantation depends on soft irq. If pl330 unable
to submit next transfer in time some samples could be lost.
The lost samples heared as sound click. In order to check
lost samples, I've installed I2S interrupt handler to signal
overflow/underflow conditions. Sometimes I saw overflow
or underflow events and heard clicks.

The patch setup cyclic transfer such a way, that transfer can
run infinitely without CPU intervention. As a result,
lost samples and clicks gone.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |  190 +++++++++++++++++++++++++--------------------------
 1 file changed, 93 insertions(+), 97 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index b080d70..a07f0c9 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -445,9 +445,6 @@ struct dma_pl330_chan {
 	int burst_sz; /* the peripheral fifo width */
 	int burst_len; /* the number of burst */
 	dma_addr_t fifo_addr;
-
-	/* for cyclic capability */
-	bool cyclic;
 };
 
 struct pl330_dmac {
@@ -529,6 +526,10 @@ struct dma_pl330_desc {
 	unsigned peri:5;
 	/* Hook to attach to DMAC's list of reqs with due callback */
 	struct list_head rqd;
+
+	/* For cyclic capability */
+	bool cyclic;
+	size_t num_periods;
 };
 
 struct _xfer_spec {
@@ -1322,16 +1323,19 @@ static inline int _setup_loops(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+static inline int _setup_xfer(unsigned dry_run, u8 buf[], u32 period,
 		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
+	struct pl330_reqcfg *rqcfg = &pxs->desc->rqcfg;
 	int off = 0;
 
 	/* DMAMOV SAR, x->src_addr */
-	off += _emit_MOV(dry_run, &buf[off], SAR, x->src_addr);
+	off += _emit_MOV(dry_run, &buf[off], SAR,
+		x->src_addr + rqcfg->src_inc * period * x->bytes);
 	/* DMAMOV DAR, x->dst_addr */
-	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
+	off += _emit_MOV(dry_run, &buf[off], DAR,
+		x->dst_addr + rqcfg->dst_inc * period * x->bytes);
 
 	/* Setup Loop(s) */
 	off += _setup_loops(dry_run, &buf[off], pxs);
@@ -1350,23 +1354,41 @@ static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
 	struct pl330_xfer *x;
 	u8 *buf = req->mc_cpu;
 	int off = 0;
+	int period;
+	int again_off;
 
 	PL330_DBGMC_START(req->mc_bus);
 
 	/* DMAMOV CCR, ccr */
 	off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr);
+	again_off = off;
 
 	x = &pxs->desc->px;
 	/* Error if xfer length is not aligned at burst size */
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(dry_run, &buf[off], pxs);
+	for (period = 0; period < pxs->desc->num_periods; period++) {
+		off += _setup_xfer(dry_run, &buf[off], period, pxs);
 
-	/* DMASEV peripheral/event */
-	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
-	/* DMAEND */
-	off += _emit_END(dry_run, &buf[off]);
+		/* DMASEV peripheral/event */
+		off += _emit_SEV(dry_run, &buf[off], thrd->ev);
+	}
+
+	if (!pxs->desc->cyclic) {
+		/* DMAEND */
+		off += _emit_END(dry_run, &buf[off]);
+	} else {
+		struct _arg_LPEND lpend;
+		/* LP */
+		off += _emit_LP(dry_run, &buf[off], 0, 255);
+		/* LPEND */
+		lpend.cond = ALWAYS;
+		lpend.forever = false;
+		lpend.loop = 0;
+		lpend.bjump = off - again_off;
+		off += _emit_LPEND(dry_run, &buf[off], &lpend);
+	}
 
 	return off;
 }
@@ -1629,12 +1651,13 @@ static int pl330_update(struct pl330_dmac *pl330)
 
 			/* Detach the req */
 			descdone = thrd->req[active].desc;
-			thrd->req[active].desc = NULL;
-
-			thrd->req_running = -1;
 
-			/* Get going again ASAP */
-			_start(thrd);
+			if (!descdone->cyclic) {
+				thrd->req[active].desc = NULL;
+				thrd->req_running = -1;
+				/* Get going again ASAP */
+				_start(thrd);
+			}
 
 			/* For now, just make a list of callbacks to be done */
 			list_add_tail(&descdone->rqd, &pl330->req_done);
@@ -2013,12 +2036,27 @@ static void pl330_tasklet(unsigned long data)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Pick up ripe tomatoes */
-	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
+	list_for_each_entry_safe(desc, _dt, &pch->work_list, node) {
 		if (desc->status == DONE) {
-			if (!pch->cyclic)
+			if (!desc->cyclic) {
 				dma_cookie_complete(&desc->txd);
-			list_move_tail(&desc->node, &pch->completed_list);
+				list_move_tail(&desc->node, &pch->completed_list);
+			} else {
+				dma_async_tx_callback callback;
+				void *callback_param;
+
+				desc->status = BUSY;
+				callback = desc->txd.callback;
+				callback_param = desc->txd.callback_param;
+
+				if (callback) {
+					spin_unlock_irqrestore(&pch->lock, flags);
+					callback(callback_param);
+					spin_lock_irqsave(&pch->lock, flags);
+				}
+			}
 		}
+	}
 
 	/* Try to submit a req imm. next to the last completed cookie */
 	fill_queue(pch);
@@ -2045,19 +2083,8 @@ static void pl330_tasklet(unsigned long data)
 		callback = desc->txd.callback;
 		callback_param = desc->txd.callback_param;
 
-		if (pch->cyclic) {
-			desc->status = PREP;
-			list_move_tail(&desc->node, &pch->work_list);
-			if (power_down) {
-				spin_lock(&pch->thread->dmac->lock);
-				_start(pch->thread);
-				spin_unlock(&pch->thread->dmac->lock);
-				power_down = false;
-			}
-		} else {
-			desc->status = FREE;
-			list_move_tail(&desc->node, &pch->dmac->desc_pool);
-		}
+		desc->status = FREE;
+		list_move_tail(&desc->node, &pch->dmac->desc_pool);
 
 		dma_descriptor_unmap(&desc->txd);
 
@@ -2117,7 +2144,6 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	dma_cookie_init(chan);
-	pch->cyclic = false;
 
 	pch->thread = pl330_request_channel(pl330);
 	if (!pch->thread) {
@@ -2235,8 +2261,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
 	pl330_release_channel(pch->thread);
 	pch->thread = NULL;
 
-	if (pch->cyclic)
-		list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
+	list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
 
 	spin_unlock_irqrestore(&pch->lock, flags);
 	pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
@@ -2290,7 +2315,7 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 
 	/* Check in pending list */
 	list_for_each_entry(desc, &pch->work_list, node) {
-		if (desc->status == DONE)
+		if (desc->status == DONE && !desc->cyclic)
 			transferred = desc->bytes_requested;
 		else if (running && desc == running)
 			transferred =
@@ -2361,12 +2386,8 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	/* Assign cookies to all nodes */
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
-		if (pch->cyclic) {
-			desc->txd.callback = last->txd.callback;
-			desc->txd.callback_param = last->txd.callback_param;
-		}
-		desc->last = false;
 
+		desc->last = false;
 		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->submitted_list);
@@ -2466,6 +2487,9 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->peri = peri_id ? pch->chan.chan_id : 0;
 	desc->rqcfg.pcfg = &pch->dmac->pcfg;
 
+	desc->cyclic = false;
+	desc->num_periods = 1;
+
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
 	return desc;
@@ -2535,10 +2559,8 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		size_t period_len, enum dma_transfer_direction direction,
 		unsigned long flags)
 {
-	struct dma_pl330_desc *desc = NULL, *first = NULL;
+	struct dma_pl330_desc *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct pl330_dmac *pl330 = pch->dmac;
-	unsigned int i;
 	dma_addr_t dst;
 	dma_addr_t src;
 
@@ -2551,65 +2573,39 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		return NULL;
 	}
 
-	for (i = 0; i < len / period_len; i++) {
-		desc = pl330_get_desc(pch);
-		if (!desc) {
-			dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
-				__func__, __LINE__);
-
-			if (!first)
-				return NULL;
-
-			spin_lock_irqsave(&pl330->pool_lock, flags);
-
-			while (!list_empty(&first->node)) {
-				desc = list_entry(first->node.next,
-						struct dma_pl330_desc, node);
-				list_move_tail(&desc->node, &pl330->desc_pool);
-			}
-
-			list_move_tail(&first->node, &pl330->desc_pool);
-
-			spin_unlock_irqrestore(&pl330->pool_lock, flags);
+	desc = pl330_get_desc(pch);
+	if (!desc) {
+		dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
+			__func__, __LINE__);
 
 			return NULL;
-		}
-
-		switch (direction) {
-		case DMA_MEM_TO_DEV:
-			desc->rqcfg.src_inc = 1;
-			desc->rqcfg.dst_inc = 0;
-			src = dma_addr;
-			dst = pch->fifo_addr;
-			break;
-		case DMA_DEV_TO_MEM:
-			desc->rqcfg.src_inc = 0;
-			desc->rqcfg.dst_inc = 1;
-			src = pch->fifo_addr;
-			dst = dma_addr;
-			break;
-		default:
-			break;
-		}
-
-		desc->rqtype = direction;
-		desc->rqcfg.brst_size = pch->burst_sz;
-		desc->rqcfg.brst_len = 1;
-		desc->bytes_requested = period_len;
-		fill_px(&desc->px, dst, src, period_len);
-
-		if (!first)
-			first = desc;
-		else
-			list_add_tail(&desc->node, &first->node);
+	}
 
-		dma_addr += period_len;
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		desc->rqcfg.src_inc = 1;
+		desc->rqcfg.dst_inc = 0;
+		src = dma_addr;
+		dst = pch->fifo_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		desc->rqcfg.src_inc = 0;
+		desc->rqcfg.dst_inc = 1;
+		src = pch->fifo_addr;
+		dst = dma_addr;
+		break;
+	default:
+		break;
 	}
 
-	if (!desc)
-		return NULL;
+	desc->rqtype = direction;
+	desc->rqcfg.brst_size = pch->burst_sz;
+	desc->rqcfg.brst_len = 1;
+	desc->bytes_requested = len;
+	fill_px(&desc->px, dst, src, period_len);
 
-	pch->cyclic = true;
+	desc->cyclic = true;
+	desc->num_periods = len / period_len;
 	desc->txd.flags = flags;
 
 	return &desc->txd;
-- 
1.7.9.5

Cleanups and improvenments for pl330 v3

[Alexander Kochetkov]

Hello,
Here is v2 series of pl330 fixes. It is rebased again linux next-20160310.
The patches were tested on rk3188 radxarock.

>8 march 2016 г., * 6:03, Vinod Koul <vinod.koul@intel.com> *:
>Overall this series looks okay, but can someone test this. I would not like
>pl330 to be roken again

Bartlomiej, could you please test the patches on Samsung Exynos4412?
Dinh, could you please test the patches on SoCFPGA?
So I will add your name as Tested-by.

> 10 march 2016 г., * 8:55, Caesar Wang <wxt@rock-chips.com> *:
> The above series patches will solve the I2S clic problem, right?

The patch "dmaengine: pl330: make cyclic transfer free runnable" fixes
sound click problem. So if you noticed sound clicks on your board,
please test the patches.

The patch "dmaengine: pl330: don't emit code for one iteration loop"
is simple improvement allows to save some bytes of pl330 MicroCode
buffer.

The patch "dmaengine: pl330: cleanup quirk pass code" is improvement
intended to hide struct pl330_dmac from low-level functions.
It partially revert changes introduced by 271e1b86e691 "dmaengine:
pl330: add quirk for broken no flushp".

[PATCH 1/3 v3] dmaengine: pl330: cleanup quirk pass code
[PATCH 2/3 v3] dmaengine: pl330: don't emit code for one iteration loop
[PATCH 3/3 v3] dmaengine: pl330: make cyclic transfer free runnable

[PATCH 1/3 v3] dmaengine: pl330: cleanup quirk pass code

[Alexander Kochetkov]

The patch partially revert changes introduced by 271e1b86e691
"dmaengine: pl330: add quirk for broken no flushp"

The patch add 'quirk' member to 'struct _xfer_spec' and
remove 'struct pl330_dmac *pl330' parameter from
many intermediate functions. The patch is intended to
hide 'struct pl330_dmac' implementation from Microcode
generation functions.

The patch is here to allow easy backporting following
patches to longterm linux 4.1.x.

Signed-off-by: Alexander Kochetkov <al.kochet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Caesar Wang <wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/dma/pl330.c |   59 ++++++++++++++++++++++++---------------------------
 1 file changed, 28 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 372b435..4abbc71 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -534,6 +534,7 @@ struct dma_pl330_desc {
 struct _xfer_spec {
 	u32 ccr;
 	struct dma_pl330_desc *desc;
+	int quirks;
 };
 
 static inline bool _queue_empty(struct pl330_thread *thrd)
@@ -1151,14 +1152,13 @@ static inline int _ldst_memtomem(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
-				 u8 buf[], const struct _xfer_spec *pxs,
-				 int cyc)
+static inline int _ldst_devtomem(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1168,7 +1168,7 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 		off += _emit_LDP(dry_run, &buf[off], cond, pxs->desc->peri);
 		off += _emit_ST(dry_run, &buf[off], ALWAYS);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1176,14 +1176,13 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 	return off;
 }
 
-static inline int _ldst_memtodev(struct pl330_dmac *pl330,
-				 unsigned dry_run, u8 buf[],
-				 const struct _xfer_spec *pxs, int cyc)
+static inline int _ldst_memtodev(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1193,7 +1192,7 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 		off += _emit_LD(dry_run, &buf[off], ALWAYS);
 		off += _emit_STP(dry_run, &buf[off], cond, pxs->desc->peri);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1201,17 +1200,17 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 	return off;
 }
 
-static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static int _bursts(unsigned dry_run, u8 buf[],
 		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 
 	switch (pxs->desc->rqtype) {
 	case DMA_MEM_TO_DEV:
-		off += _ldst_memtodev(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_memtodev(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_DEV_TO_MEM:
-		off += _ldst_devtomem(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_devtomem(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_MEM_TO_MEM:
 		off += _ldst_memtomem(dry_run, &buf[off], pxs, cyc);
@@ -1225,7 +1224,7 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 }
 
 /* Returns bytes consumed and updates bursts */
-static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static inline int _loop(unsigned dry_run, u8 buf[],
 		unsigned long *bursts, const struct _xfer_spec *pxs)
 {
 	int cyc, cycmax, szlp, szlpend, szbrst, off;
@@ -1233,7 +1232,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	struct _arg_LPEND lpend;
 
 	if (*bursts == 1)
-		return _bursts(pl330, dry_run, buf, pxs, 1);
+		return _bursts(dry_run, buf, pxs, 1);
 
 	/* Max iterations possible in DMALP is 256 */
 	if (*bursts >= 256*256) {
@@ -1251,7 +1250,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	}
 
 	szlp = _emit_LP(1, buf, 0, 0);
-	szbrst = _bursts(pl330, 1, buf, pxs, 1);
+	szbrst = _bursts(1, buf, pxs, 1);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1283,7 +1282,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	off += _emit_LP(dry_run, &buf[off], 1, lcnt1);
 	ljmp1 = off;
 
-	off += _bursts(pl330, dry_run, &buf[off], pxs, cyc);
+	off += _bursts(dry_run, &buf[off], pxs, cyc);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1306,9 +1305,8 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_loops(struct pl330_dmac *pl330,
-			       unsigned dry_run, u8 buf[],
-			       const struct _xfer_spec *pxs)
+static inline int _setup_loops(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	u32 ccr = pxs->ccr;
@@ -1317,16 +1315,15 @@ static inline int _setup_loops(struct pl330_dmac *pl330,
 
 	while (bursts) {
 		c = bursts;
-		off += _loop(pl330, dry_run, &buf[off], &c, pxs);
+		off += _loop(dry_run, &buf[off], &c, pxs);
 		bursts -= c;
 	}
 
 	return off;
 }
 
-static inline int _setup_xfer(struct pl330_dmac *pl330,
-			      unsigned dry_run, u8 buf[],
-			      const struct _xfer_spec *pxs)
+static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	int off = 0;
@@ -1337,7 +1334,7 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
 	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
 
 	/* Setup Loop(s) */
-	off += _setup_loops(pl330, dry_run, &buf[off], pxs);
+	off += _setup_loops(dry_run, &buf[off], pxs);
 
 	return off;
 }
@@ -1346,9 +1343,8 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
  * A req is a sequence of one or more xfer units.
  * Returns the number of bytes taken to setup the MC for the req.
  */
-static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
-		      struct pl330_thread *thrd, unsigned index,
-		      struct _xfer_spec *pxs)
+static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
+		unsigned index, struct _xfer_spec *pxs)
 {
 	struct _pl330_req *req = &thrd->req[index];
 	struct pl330_xfer *x;
@@ -1365,7 +1361,7 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(pl330, dry_run, &buf[off], pxs);
+	off += _setup_xfer(dry_run, &buf[off], pxs);
 
 	/* DMASEV peripheral/event */
 	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
@@ -1457,9 +1453,10 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 
 	xs.ccr = ccr;
 	xs.desc = desc;
+	xs.quirks = pl330->quirks;
 
 	/* First dry run to check if req is acceptable */
-	ret = _setup_req(pl330, 1, thrd, idx, &xs);
+	ret = _setup_req(1, thrd, idx, &xs);
 	if (ret < 0)
 		goto xfer_exit;
 
@@ -1473,7 +1470,7 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 	/* Hook the request */
 	thrd->lstenq = idx;
 	thrd->req[idx].desc = desc;
-	_setup_req(pl330, 0, thrd, idx, &xs);
+	_setup_req(0, thrd, idx, &xs);
 
 	ret = 0;
 
-- 
1.7.9.5

[PATCH 1/3 v3] dmaengine: pl330: cleanup quirk pass code

[Alexander Kochetkov]

The patch partially revert changes introduced by 271e1b86e691
"dmaengine: pl330: add quirk for broken no flushp"

The patch add 'quirk' member to 'struct _xfer_spec' and
remove 'struct pl330_dmac *pl330' parameter from
many intermediate functions. The patch is intended to
hide 'struct pl330_dmac' implementation from Microcode
generation functions.

The patch is here to allow easy backporting following
patches to longterm linux 4.1.x.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |   59 ++++++++++++++++++++++++---------------------------
 1 file changed, 28 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 372b435..4abbc71 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -534,6 +534,7 @@ struct dma_pl330_desc {
 struct _xfer_spec {
 	u32 ccr;
 	struct dma_pl330_desc *desc;
+	int quirks;
 };
 
 static inline bool _queue_empty(struct pl330_thread *thrd)
@@ -1151,14 +1152,13 @@ static inline int _ldst_memtomem(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
-				 u8 buf[], const struct _xfer_spec *pxs,
-				 int cyc)
+static inline int _ldst_devtomem(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1168,7 +1168,7 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 		off += _emit_LDP(dry_run, &buf[off], cond, pxs->desc->peri);
 		off += _emit_ST(dry_run, &buf[off], ALWAYS);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1176,14 +1176,13 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run,
 	return off;
 }
 
-static inline int _ldst_memtodev(struct pl330_dmac *pl330,
-				 unsigned dry_run, u8 buf[],
-				 const struct _xfer_spec *pxs, int cyc)
+static inline int _ldst_memtodev(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 	enum pl330_cond cond;
 
-	if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
+	if (pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)
 		cond = BURST;
 	else
 		cond = SINGLE;
@@ -1193,7 +1192,7 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 		off += _emit_LD(dry_run, &buf[off], ALWAYS);
 		off += _emit_STP(dry_run, &buf[off], cond, pxs->desc->peri);
 
-		if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
+		if (!(pxs->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP))
 			off += _emit_FLUSHP(dry_run, &buf[off],
 					    pxs->desc->peri);
 	}
@@ -1201,17 +1200,17 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330,
 	return off;
 }
 
-static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static int _bursts(unsigned dry_run, u8 buf[],
 		const struct _xfer_spec *pxs, int cyc)
 {
 	int off = 0;
 
 	switch (pxs->desc->rqtype) {
 	case DMA_MEM_TO_DEV:
-		off += _ldst_memtodev(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_memtodev(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_DEV_TO_MEM:
-		off += _ldst_devtomem(pl330, dry_run, &buf[off], pxs, cyc);
+		off += _ldst_devtomem(dry_run, &buf[off], pxs, cyc);
 		break;
 	case DMA_MEM_TO_MEM:
 		off += _ldst_memtomem(dry_run, &buf[off], pxs, cyc);
@@ -1225,7 +1224,7 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 }
 
 /* Returns bytes consumed and updates bursts */
-static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
+static inline int _loop(unsigned dry_run, u8 buf[],
 		unsigned long *bursts, const struct _xfer_spec *pxs)
 {
 	int cyc, cycmax, szlp, szlpend, szbrst, off;
@@ -1233,7 +1232,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	struct _arg_LPEND lpend;
 
 	if (*bursts == 1)
-		return _bursts(pl330, dry_run, buf, pxs, 1);
+		return _bursts(dry_run, buf, pxs, 1);
 
 	/* Max iterations possible in DMALP is 256 */
 	if (*bursts >= 256*256) {
@@ -1251,7 +1250,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	}
 
 	szlp = _emit_LP(1, buf, 0, 0);
-	szbrst = _bursts(pl330, 1, buf, pxs, 1);
+	szbrst = _bursts(1, buf, pxs, 1);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1283,7 +1282,7 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	off += _emit_LP(dry_run, &buf[off], 1, lcnt1);
 	ljmp1 = off;
 
-	off += _bursts(pl330, dry_run, &buf[off], pxs, cyc);
+	off += _bursts(dry_run, &buf[off], pxs, cyc);
 
 	lpend.cond = ALWAYS;
 	lpend.forever = false;
@@ -1306,9 +1305,8 @@ static inline int _loop(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_loops(struct pl330_dmac *pl330,
-			       unsigned dry_run, u8 buf[],
-			       const struct _xfer_spec *pxs)
+static inline int _setup_loops(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	u32 ccr = pxs->ccr;
@@ -1317,16 +1315,15 @@ static inline int _setup_loops(struct pl330_dmac *pl330,
 
 	while (bursts) {
 		c = bursts;
-		off += _loop(pl330, dry_run, &buf[off], &c, pxs);
+		off += _loop(dry_run, &buf[off], &c, pxs);
 		bursts -= c;
 	}
 
 	return off;
 }
 
-static inline int _setup_xfer(struct pl330_dmac *pl330,
-			      unsigned dry_run, u8 buf[],
-			      const struct _xfer_spec *pxs)
+static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
 	int off = 0;
@@ -1337,7 +1334,7 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
 	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
 
 	/* Setup Loop(s) */
-	off += _setup_loops(pl330, dry_run, &buf[off], pxs);
+	off += _setup_loops(dry_run, &buf[off], pxs);
 
 	return off;
 }
@@ -1346,9 +1343,8 @@ static inline int _setup_xfer(struct pl330_dmac *pl330,
  * A req is a sequence of one or more xfer units.
  * Returns the number of bytes taken to setup the MC for the req.
  */
-static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
-		      struct pl330_thread *thrd, unsigned index,
-		      struct _xfer_spec *pxs)
+static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
+		unsigned index, struct _xfer_spec *pxs)
 {
 	struct _pl330_req *req = &thrd->req[index];
 	struct pl330_xfer *x;
@@ -1365,7 +1361,7 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run,
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(pl330, dry_run, &buf[off], pxs);
+	off += _setup_xfer(dry_run, &buf[off], pxs);
 
 	/* DMASEV peripheral/event */
 	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
@@ -1457,9 +1453,10 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 
 	xs.ccr = ccr;
 	xs.desc = desc;
+	xs.quirks = pl330->quirks;
 
 	/* First dry run to check if req is acceptable */
-	ret = _setup_req(pl330, 1, thrd, idx, &xs);
+	ret = _setup_req(1, thrd, idx, &xs);
 	if (ret < 0)
 		goto xfer_exit;
 
@@ -1473,7 +1470,7 @@ static int pl330_submit_req(struct pl330_thread *thrd,
 	/* Hook the request */
 	thrd->lstenq = idx;
 	thrd->req[idx].desc = desc;
-	_setup_req(pl330, 0, thrd, idx, &xs);
+	_setup_req(0, thrd, idx, &xs);
 
 	ret = 0;
 
-- 
1.7.9.5

[PATCH 2/3 v3] dmaengine: pl330: don't emit code for one iteration loop

[Alexander Kochetkov]

The patch remove one iteration outer loop in the _loop().
Removing loop saves 4 bytes of MicroCode buffer.

    DMALP_0 0
    ...
    DMALPENDA_0 bjmpto_9

Signed-off-by: Alexander Kochetkov <al.kochet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Caesar Wang <wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/dma/pl330.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 4abbc71..b080d70 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1258,7 +1258,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = 0;
 	szlpend = _emit_LPEND(1, buf, &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		szlp *= 2;
 		szlpend *= 2;
 	}
@@ -1274,7 +1274,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 
 	off = 0;
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		off += _emit_LP(dry_run, &buf[off], 0, lcnt0);
 		ljmp0 = off;
 	}
@@ -1290,7 +1290,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = off - ljmp1;
 	off += _emit_LPEND(dry_run, &buf[off], &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		lpend.cond = ALWAYS;
 		lpend.forever = false;
 		lpend.loop = 0;
@@ -1299,7 +1299,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	}
 
 	*bursts = lcnt1 * cyc;
-	if (lcnt0)
+	if (lcnt0 > 1)
 		*bursts *= lcnt0;
 
 	return off;
-- 
1.7.9.5

[PATCH 2/3 v3] dmaengine: pl330: don't emit code for one iteration loop

[Alexander Kochetkov]

The patch remove one iteration outer loop in the _loop().
Removing loop saves 4 bytes of MicroCode buffer.

    DMALP_0 0
    ...
    DMALPENDA_0 bjmpto_9

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 4abbc71..b080d70 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1258,7 +1258,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = 0;
 	szlpend = _emit_LPEND(1, buf, &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		szlp *= 2;
 		szlpend *= 2;
 	}
@@ -1274,7 +1274,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 
 	off = 0;
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		off += _emit_LP(dry_run, &buf[off], 0, lcnt0);
 		ljmp0 = off;
 	}
@@ -1290,7 +1290,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	lpend.bjump = off - ljmp1;
 	off += _emit_LPEND(dry_run, &buf[off], &lpend);
 
-	if (lcnt0) {
+	if (lcnt0 > 1) {
 		lpend.cond = ALWAYS;
 		lpend.forever = false;
 		lpend.loop = 0;
@@ -1299,7 +1299,7 @@ static inline int _loop(unsigned dry_run, u8 buf[],
 	}
 
 	*bursts = lcnt1 * cyc;
-	if (lcnt0)
+	if (lcnt0 > 1)
 		*bursts *= lcnt0;
 
 	return off;
-- 
1.7.9.5

[PATCH 3/3 v3] dmaengine: pl330: make cyclic transfer free runnable

[Alexander Kochetkov]

The patch solve the I2S click problem on rk3188. Actually
all the devices using pl330 should have I2S click problem
due to pl330 cyclic transfer implementation.

Current implemantation depends on soft irq. If pl330 unable
to submit next transfer in time some samples could be lost.
The lost samples heared as sound click. In order to check
lost samples, I've installed I2S interrupt handler to signal
overflow/underflow conditions. Sometimes I saw overflow
or underflow events and heard clicks.

The patch setup cyclic transfer such a way, that transfer can
run infinitely without CPU intervention. As a result,
lost samples and clicks gone.

Signed-off-by: Alexander Kochetkov <al.kochet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Reviewed-by: Caesar Wang <wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
 drivers/dma/pl330.c |  190 +++++++++++++++++++++++++--------------------------
 1 file changed, 93 insertions(+), 97 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index b080d70..a07f0c9 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -445,9 +445,6 @@ struct dma_pl330_chan {
 	int burst_sz; /* the peripheral fifo width */
 	int burst_len; /* the number of burst */
 	dma_addr_t fifo_addr;
-
-	/* for cyclic capability */
-	bool cyclic;
 };
 
 struct pl330_dmac {
@@ -529,6 +526,10 @@ struct dma_pl330_desc {
 	unsigned peri:5;
 	/* Hook to attach to DMAC's list of reqs with due callback */
 	struct list_head rqd;
+
+	/* For cyclic capability */
+	bool cyclic;
+	size_t num_periods;
 };
 
 struct _xfer_spec {
@@ -1322,16 +1323,19 @@ static inline int _setup_loops(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+static inline int _setup_xfer(unsigned dry_run, u8 buf[], u32 period,
 		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
+	struct pl330_reqcfg *rqcfg = &pxs->desc->rqcfg;
 	int off = 0;
 
 	/* DMAMOV SAR, x->src_addr */
-	off += _emit_MOV(dry_run, &buf[off], SAR, x->src_addr);
+	off += _emit_MOV(dry_run, &buf[off], SAR,
+		x->src_addr + rqcfg->src_inc * period * x->bytes);
 	/* DMAMOV DAR, x->dst_addr */
-	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
+	off += _emit_MOV(dry_run, &buf[off], DAR,
+		x->dst_addr + rqcfg->dst_inc * period * x->bytes);
 
 	/* Setup Loop(s) */
 	off += _setup_loops(dry_run, &buf[off], pxs);
@@ -1350,23 +1354,41 @@ static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
 	struct pl330_xfer *x;
 	u8 *buf = req->mc_cpu;
 	int off = 0;
+	int period;
+	int again_off;
 
 	PL330_DBGMC_START(req->mc_bus);
 
 	/* DMAMOV CCR, ccr */
 	off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr);
+	again_off = off;
 
 	x = &pxs->desc->px;
 	/* Error if xfer length is not aligned at burst size */
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(dry_run, &buf[off], pxs);
+	for (period = 0; period < pxs->desc->num_periods; period++) {
+		off += _setup_xfer(dry_run, &buf[off], period, pxs);
 
-	/* DMASEV peripheral/event */
-	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
-	/* DMAEND */
-	off += _emit_END(dry_run, &buf[off]);
+		/* DMASEV peripheral/event */
+		off += _emit_SEV(dry_run, &buf[off], thrd->ev);
+	}
+
+	if (!pxs->desc->cyclic) {
+		/* DMAEND */
+		off += _emit_END(dry_run, &buf[off]);
+	} else {
+		struct _arg_LPEND lpend;
+		/* LP */
+		off += _emit_LP(dry_run, &buf[off], 0, 255);
+		/* LPEND */
+		lpend.cond = ALWAYS;
+		lpend.forever = false;
+		lpend.loop = 0;
+		lpend.bjump = off - again_off;
+		off += _emit_LPEND(dry_run, &buf[off], &lpend);
+	}
 
 	return off;
 }
@@ -1629,12 +1651,13 @@ static int pl330_update(struct pl330_dmac *pl330)
 
 			/* Detach the req */
 			descdone = thrd->req[active].desc;
-			thrd->req[active].desc = NULL;
-
-			thrd->req_running = -1;
 
-			/* Get going again ASAP */
-			_start(thrd);
+			if (!descdone->cyclic) {
+				thrd->req[active].desc = NULL;
+				thrd->req_running = -1;
+				/* Get going again ASAP */
+				_start(thrd);
+			}
 
 			/* For now, just make a list of callbacks to be done */
 			list_add_tail(&descdone->rqd, &pl330->req_done);
@@ -2013,12 +2036,27 @@ static void pl330_tasklet(unsigned long data)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Pick up ripe tomatoes */
-	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
+	list_for_each_entry_safe(desc, _dt, &pch->work_list, node) {
 		if (desc->status == DONE) {
-			if (!pch->cyclic)
+			if (!desc->cyclic) {
 				dma_cookie_complete(&desc->txd);
-			list_move_tail(&desc->node, &pch->completed_list);
+				list_move_tail(&desc->node, &pch->completed_list);
+			} else {
+				dma_async_tx_callback callback;
+				void *callback_param;
+
+				desc->status = BUSY;
+				callback = desc->txd.callback;
+				callback_param = desc->txd.callback_param;
+
+				if (callback) {
+					spin_unlock_irqrestore(&pch->lock, flags);
+					callback(callback_param);
+					spin_lock_irqsave(&pch->lock, flags);
+				}
+			}
 		}
+	}
 
 	/* Try to submit a req imm. next to the last completed cookie */
 	fill_queue(pch);
@@ -2045,19 +2083,8 @@ static void pl330_tasklet(unsigned long data)
 		callback = desc->txd.callback;
 		callback_param = desc->txd.callback_param;
 
-		if (pch->cyclic) {
-			desc->status = PREP;
-			list_move_tail(&desc->node, &pch->work_list);
-			if (power_down) {
-				spin_lock(&pch->thread->dmac->lock);
-				_start(pch->thread);
-				spin_unlock(&pch->thread->dmac->lock);
-				power_down = false;
-			}
-		} else {
-			desc->status = FREE;
-			list_move_tail(&desc->node, &pch->dmac->desc_pool);
-		}
+		desc->status = FREE;
+		list_move_tail(&desc->node, &pch->dmac->desc_pool);
 
 		dma_descriptor_unmap(&desc->txd);
 
@@ -2117,7 +2144,6 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	dma_cookie_init(chan);
-	pch->cyclic = false;
 
 	pch->thread = pl330_request_channel(pl330);
 	if (!pch->thread) {
@@ -2235,8 +2261,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
 	pl330_release_channel(pch->thread);
 	pch->thread = NULL;
 
-	if (pch->cyclic)
-		list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
+	list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
 
 	spin_unlock_irqrestore(&pch->lock, flags);
 	pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
@@ -2290,7 +2315,7 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 
 	/* Check in pending list */
 	list_for_each_entry(desc, &pch->work_list, node) {
-		if (desc->status == DONE)
+		if (desc->status == DONE && !desc->cyclic)
 			transferred = desc->bytes_requested;
 		else if (running && desc == running)
 			transferred =
@@ -2361,12 +2386,8 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	/* Assign cookies to all nodes */
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
-		if (pch->cyclic) {
-			desc->txd.callback = last->txd.callback;
-			desc->txd.callback_param = last->txd.callback_param;
-		}
-		desc->last = false;
 
+		desc->last = false;
 		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->submitted_list);
@@ -2466,6 +2487,9 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->peri = peri_id ? pch->chan.chan_id : 0;
 	desc->rqcfg.pcfg = &pch->dmac->pcfg;
 
+	desc->cyclic = false;
+	desc->num_periods = 1;
+
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
 	return desc;
@@ -2535,10 +2559,8 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		size_t period_len, enum dma_transfer_direction direction,
 		unsigned long flags)
 {
-	struct dma_pl330_desc *desc = NULL, *first = NULL;
+	struct dma_pl330_desc *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct pl330_dmac *pl330 = pch->dmac;
-	unsigned int i;
 	dma_addr_t dst;
 	dma_addr_t src;
 
@@ -2551,65 +2573,39 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		return NULL;
 	}
 
-	for (i = 0; i < len / period_len; i++) {
-		desc = pl330_get_desc(pch);
-		if (!desc) {
-			dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
-				__func__, __LINE__);
-
-			if (!first)
-				return NULL;
-
-			spin_lock_irqsave(&pl330->pool_lock, flags);
-
-			while (!list_empty(&first->node)) {
-				desc = list_entry(first->node.next,
-						struct dma_pl330_desc, node);
-				list_move_tail(&desc->node, &pl330->desc_pool);
-			}
-
-			list_move_tail(&first->node, &pl330->desc_pool);
-
-			spin_unlock_irqrestore(&pl330->pool_lock, flags);
+	desc = pl330_get_desc(pch);
+	if (!desc) {
+		dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
+			__func__, __LINE__);
 
 			return NULL;
-		}
-
-		switch (direction) {
-		case DMA_MEM_TO_DEV:
-			desc->rqcfg.src_inc = 1;
-			desc->rqcfg.dst_inc = 0;
-			src = dma_addr;
-			dst = pch->fifo_addr;
-			break;
-		case DMA_DEV_TO_MEM:
-			desc->rqcfg.src_inc = 0;
-			desc->rqcfg.dst_inc = 1;
-			src = pch->fifo_addr;
-			dst = dma_addr;
-			break;
-		default:
-			break;
-		}
-
-		desc->rqtype = direction;
-		desc->rqcfg.brst_size = pch->burst_sz;
-		desc->rqcfg.brst_len = 1;
-		desc->bytes_requested = period_len;
-		fill_px(&desc->px, dst, src, period_len);
-
-		if (!first)
-			first = desc;
-		else
-			list_add_tail(&desc->node, &first->node);
+	}
 
-		dma_addr += period_len;
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		desc->rqcfg.src_inc = 1;
+		desc->rqcfg.dst_inc = 0;
+		src = dma_addr;
+		dst = pch->fifo_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		desc->rqcfg.src_inc = 0;
+		desc->rqcfg.dst_inc = 1;
+		src = pch->fifo_addr;
+		dst = dma_addr;
+		break;
+	default:
+		break;
 	}
 
-	if (!desc)
-		return NULL;
+	desc->rqtype = direction;
+	desc->rqcfg.brst_size = pch->burst_sz;
+	desc->rqcfg.brst_len = 1;
+	desc->bytes_requested = len;
+	fill_px(&desc->px, dst, src, period_len);
 
-	pch->cyclic = true;
+	desc->cyclic = true;
+	desc->num_periods = len / period_len;
 	desc->txd.flags = flags;
 
 	return &desc->txd;
-- 
1.7.9.5

[PATCH 3/3 v3] dmaengine: pl330: make cyclic transfer free runnable

[Alexander Kochetkov]

The patch solve the I2S click problem on rk3188. Actually
all the devices using pl330 should have I2S click problem
due to pl330 cyclic transfer implementation.

Current implemantation depends on soft irq. If pl330 unable
to submit next transfer in time some samples could be lost.
The lost samples heared as sound click. In order to check
lost samples, I've installed I2S interrupt handler to signal
overflow/underflow conditions. Sometimes I saw overflow
or underflow events and heard clicks.

The patch setup cyclic transfer such a way, that transfer can
run infinitely without CPU intervention. As a result,
lost samples and clicks gone.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Caesar Wang <wxt@rock-chips.com>
---
 drivers/dma/pl330.c |  190 +++++++++++++++++++++++++--------------------------
 1 file changed, 93 insertions(+), 97 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index b080d70..a07f0c9 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -445,9 +445,6 @@ struct dma_pl330_chan {
 	int burst_sz; /* the peripheral fifo width */
 	int burst_len; /* the number of burst */
 	dma_addr_t fifo_addr;
-
-	/* for cyclic capability */
-	bool cyclic;
 };
 
 struct pl330_dmac {
@@ -529,6 +526,10 @@ struct dma_pl330_desc {
 	unsigned peri:5;
 	/* Hook to attach to DMAC's list of reqs with due callback */
 	struct list_head rqd;
+
+	/* For cyclic capability */
+	bool cyclic;
+	size_t num_periods;
 };
 
 struct _xfer_spec {
@@ -1322,16 +1323,19 @@ static inline int _setup_loops(unsigned dry_run, u8 buf[],
 	return off;
 }
 
-static inline int _setup_xfer(unsigned dry_run, u8 buf[],
+static inline int _setup_xfer(unsigned dry_run, u8 buf[], u32 period,
 		const struct _xfer_spec *pxs)
 {
 	struct pl330_xfer *x = &pxs->desc->px;
+	struct pl330_reqcfg *rqcfg = &pxs->desc->rqcfg;
 	int off = 0;
 
 	/* DMAMOV SAR, x->src_addr */
-	off += _emit_MOV(dry_run, &buf[off], SAR, x->src_addr);
+	off += _emit_MOV(dry_run, &buf[off], SAR,
+		x->src_addr + rqcfg->src_inc * period * x->bytes);
 	/* DMAMOV DAR, x->dst_addr */
-	off += _emit_MOV(dry_run, &buf[off], DAR, x->dst_addr);
+	off += _emit_MOV(dry_run, &buf[off], DAR,
+		x->dst_addr + rqcfg->dst_inc * period * x->bytes);
 
 	/* Setup Loop(s) */
 	off += _setup_loops(dry_run, &buf[off], pxs);
@@ -1350,23 +1354,41 @@ static int _setup_req(unsigned dry_run, struct pl330_thread *thrd,
 	struct pl330_xfer *x;
 	u8 *buf = req->mc_cpu;
 	int off = 0;
+	int period;
+	int again_off;
 
 	PL330_DBGMC_START(req->mc_bus);
 
 	/* DMAMOV CCR, ccr */
 	off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr);
+	again_off = off;
 
 	x = &pxs->desc->px;
 	/* Error if xfer length is not aligned at burst size */
 	if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr)))
 		return -EINVAL;
 
-	off += _setup_xfer(dry_run, &buf[off], pxs);
+	for (period = 0; period < pxs->desc->num_periods; period++) {
+		off += _setup_xfer(dry_run, &buf[off], period, pxs);
 
-	/* DMASEV peripheral/event */
-	off += _emit_SEV(dry_run, &buf[off], thrd->ev);
-	/* DMAEND */
-	off += _emit_END(dry_run, &buf[off]);
+		/* DMASEV peripheral/event */
+		off += _emit_SEV(dry_run, &buf[off], thrd->ev);
+	}
+
+	if (!pxs->desc->cyclic) {
+		/* DMAEND */
+		off += _emit_END(dry_run, &buf[off]);
+	} else {
+		struct _arg_LPEND lpend;
+		/* LP */
+		off += _emit_LP(dry_run, &buf[off], 0, 255);
+		/* LPEND */
+		lpend.cond = ALWAYS;
+		lpend.forever = false;
+		lpend.loop = 0;
+		lpend.bjump = off - again_off;
+		off += _emit_LPEND(dry_run, &buf[off], &lpend);
+	}
 
 	return off;
 }
@@ -1629,12 +1651,13 @@ static int pl330_update(struct pl330_dmac *pl330)
 
 			/* Detach the req */
 			descdone = thrd->req[active].desc;
-			thrd->req[active].desc = NULL;
-
-			thrd->req_running = -1;
 
-			/* Get going again ASAP */
-			_start(thrd);
+			if (!descdone->cyclic) {
+				thrd->req[active].desc = NULL;
+				thrd->req_running = -1;
+				/* Get going again ASAP */
+				_start(thrd);
+			}
 
 			/* For now, just make a list of callbacks to be done */
 			list_add_tail(&descdone->rqd, &pl330->req_done);
@@ -2013,12 +2036,27 @@ static void pl330_tasklet(unsigned long data)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Pick up ripe tomatoes */
-	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
+	list_for_each_entry_safe(desc, _dt, &pch->work_list, node) {
 		if (desc->status == DONE) {
-			if (!pch->cyclic)
+			if (!desc->cyclic) {
 				dma_cookie_complete(&desc->txd);
-			list_move_tail(&desc->node, &pch->completed_list);
+				list_move_tail(&desc->node, &pch->completed_list);
+			} else {
+				dma_async_tx_callback callback;
+				void *callback_param;
+
+				desc->status = BUSY;
+				callback = desc->txd.callback;
+				callback_param = desc->txd.callback_param;
+
+				if (callback) {
+					spin_unlock_irqrestore(&pch->lock, flags);
+					callback(callback_param);
+					spin_lock_irqsave(&pch->lock, flags);
+				}
+			}
 		}
+	}
 
 	/* Try to submit a req imm. next to the last completed cookie */
 	fill_queue(pch);
@@ -2045,19 +2083,8 @@ static void pl330_tasklet(unsigned long data)
 		callback = desc->txd.callback;
 		callback_param = desc->txd.callback_param;
 
-		if (pch->cyclic) {
-			desc->status = PREP;
-			list_move_tail(&desc->node, &pch->work_list);
-			if (power_down) {
-				spin_lock(&pch->thread->dmac->lock);
-				_start(pch->thread);
-				spin_unlock(&pch->thread->dmac->lock);
-				power_down = false;
-			}
-		} else {
-			desc->status = FREE;
-			list_move_tail(&desc->node, &pch->dmac->desc_pool);
-		}
+		desc->status = FREE;
+		list_move_tail(&desc->node, &pch->dmac->desc_pool);
 
 		dma_descriptor_unmap(&desc->txd);
 
@@ -2117,7 +2144,6 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	dma_cookie_init(chan);
-	pch->cyclic = false;
 
 	pch->thread = pl330_request_channel(pl330);
 	if (!pch->thread) {
@@ -2235,8 +2261,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan)
 	pl330_release_channel(pch->thread);
 	pch->thread = NULL;
 
-	if (pch->cyclic)
-		list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
+	list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool);
 
 	spin_unlock_irqrestore(&pch->lock, flags);
 	pm_runtime_mark_last_busy(pch->dmac->ddma.dev);
@@ -2290,7 +2315,7 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 
 	/* Check in pending list */
 	list_for_each_entry(desc, &pch->work_list, node) {
-		if (desc->status == DONE)
+		if (desc->status == DONE && !desc->cyclic)
 			transferred = desc->bytes_requested;
 		else if (running && desc == running)
 			transferred =
@@ -2361,12 +2386,8 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	/* Assign cookies to all nodes */
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
-		if (pch->cyclic) {
-			desc->txd.callback = last->txd.callback;
-			desc->txd.callback_param = last->txd.callback_param;
-		}
-		desc->last = false;
 
+		desc->last = false;
 		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->submitted_list);
@@ -2466,6 +2487,9 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
 	desc->peri = peri_id ? pch->chan.chan_id : 0;
 	desc->rqcfg.pcfg = &pch->dmac->pcfg;
 
+	desc->cyclic = false;
+	desc->num_periods = 1;
+
 	dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
 
 	return desc;
@@ -2535,10 +2559,8 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		size_t period_len, enum dma_transfer_direction direction,
 		unsigned long flags)
 {
-	struct dma_pl330_desc *desc = NULL, *first = NULL;
+	struct dma_pl330_desc *desc = NULL;
 	struct dma_pl330_chan *pch = to_pchan(chan);
-	struct pl330_dmac *pl330 = pch->dmac;
-	unsigned int i;
 	dma_addr_t dst;
 	dma_addr_t src;
 
@@ -2551,65 +2573,39 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
 		return NULL;
 	}
 
-	for (i = 0; i < len / period_len; i++) {
-		desc = pl330_get_desc(pch);
-		if (!desc) {
-			dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
-				__func__, __LINE__);
-
-			if (!first)
-				return NULL;
-
-			spin_lock_irqsave(&pl330->pool_lock, flags);
-
-			while (!list_empty(&first->node)) {
-				desc = list_entry(first->node.next,
-						struct dma_pl330_desc, node);
-				list_move_tail(&desc->node, &pl330->desc_pool);
-			}
-
-			list_move_tail(&first->node, &pl330->desc_pool);
-
-			spin_unlock_irqrestore(&pl330->pool_lock, flags);
+	desc = pl330_get_desc(pch);
+	if (!desc) {
+		dev_err(pch->dmac->ddma.dev, "%s:%d Unable to fetch desc\n",
+			__func__, __LINE__);
 
 			return NULL;
-		}
-
-		switch (direction) {
-		case DMA_MEM_TO_DEV:
-			desc->rqcfg.src_inc = 1;
-			desc->rqcfg.dst_inc = 0;
-			src = dma_addr;
-			dst = pch->fifo_addr;
-			break;
-		case DMA_DEV_TO_MEM:
-			desc->rqcfg.src_inc = 0;
-			desc->rqcfg.dst_inc = 1;
-			src = pch->fifo_addr;
-			dst = dma_addr;
-			break;
-		default:
-			break;
-		}
-
-		desc->rqtype = direction;
-		desc->rqcfg.brst_size = pch->burst_sz;
-		desc->rqcfg.brst_len = 1;
-		desc->bytes_requested = period_len;
-		fill_px(&desc->px, dst, src, period_len);
-
-		if (!first)
-			first = desc;
-		else
-			list_add_tail(&desc->node, &first->node);
+	}
 
-		dma_addr += period_len;
+	switch (direction) {
+	case DMA_MEM_TO_DEV:
+		desc->rqcfg.src_inc = 1;
+		desc->rqcfg.dst_inc = 0;
+		src = dma_addr;
+		dst = pch->fifo_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		desc->rqcfg.src_inc = 0;
+		desc->rqcfg.dst_inc = 1;
+		src = pch->fifo_addr;
+		dst = dma_addr;
+		break;
+	default:
+		break;
 	}
 
-	if (!desc)
-		return NULL;
+	desc->rqtype = direction;
+	desc->rqcfg.brst_size = pch->burst_sz;
+	desc->rqcfg.brst_len = 1;
+	desc->bytes_requested = len;
+	fill_px(&desc->px, dst, src, period_len);
 
-	pch->cyclic = true;
+	desc->cyclic = true;
+	desc->num_periods = len / period_len;
 	desc->txd.flags = flags;
 
 	return &desc->txd;
-- 
1.7.9.5