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author | Frank Mori Hess <fmh6jj@gmail.com> | 2018-04-18 20:31:06 -0400 |
---|---|---|
committer | Vinod Koul <vkoul@kernel.org> | 2018-05-03 14:31:56 +0530 |
commit | 1d48745b192a7a45bbdd3557b4c039609569ca41 (patch) | |
tree | d90426df26b3f9e000e84783c3a0b539ef42dd19 /drivers | |
parent | 60cc43fc888428bb2f18f08997432d426a243338 (diff) | |
download | linux-stable-1d48745b192a7a45bbdd3557b4c039609569ca41.tar.gz linux-stable-1d48745b192a7a45bbdd3557b4c039609569ca41.tar.bz2 linux-stable-1d48745b192a7a45bbdd3557b4c039609569ca41.zip |
dmaengine: pl330: flush before wait, and add dev burst support.
Do DMAFLUSHP _before_ the first DMAWFP to ensure controller
and peripheral are in agreement about dma request state before first
transfer. Add support for burst transfers to/from peripherals. In the new
scheme, the controller does as many burst transfers as it can then
transfers the remaining dregs with either single transfers for
peripherals, or with a reduced size burst for memory-to-memory transfers.
Signed-off-by: Frank Mori Hess <fmh6jj@gmail.com>
Tested-by: Frank Mori Hess <fmh6jj@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/dma/pl330.c | 209 |
1 files changed, 159 insertions, 50 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index de1fd59fe136..6237069001c4 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -27,6 +27,7 @@ #include <linux/of_dma.h> #include <linux/err.h> #include <linux/pm_runtime.h> +#include <linux/bug.h> #include "dmaengine.h" #define PL330_MAX_CHAN 8 @@ -1094,51 +1095,96 @@ 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 u32 _emit_load(unsigned int dry_run, u8 buf[], + enum pl330_cond cond, enum dma_transfer_direction direction, + u8 peri) { int off = 0; - enum pl330_cond cond; - if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) - cond = BURST; - else - cond = SINGLE; + switch (direction) { + case DMA_MEM_TO_MEM: + /* fall through */ + case DMA_MEM_TO_DEV: + off += _emit_LD(dry_run, &buf[off], cond); + break; - while (cyc--) { - off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri); - off += _emit_LDP(dry_run, &buf[off], cond, pxs->desc->peri); - off += _emit_ST(dry_run, &buf[off], ALWAYS); + case DMA_DEV_TO_MEM: + if (cond == ALWAYS) { + off += _emit_LDP(dry_run, &buf[off], SINGLE, + peri); + off += _emit_LDP(dry_run, &buf[off], BURST, + peri); + } else { + off += _emit_LDP(dry_run, &buf[off], cond, + peri); + } + break; - if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)) - off += _emit_FLUSHP(dry_run, &buf[off], - pxs->desc->peri); + default: + /* this code should be unreachable */ + WARN_ON(1); + break; } return off; } -static inline int _ldst_memtodev(struct pl330_dmac *pl330, +static inline u32 _emit_store(unsigned int dry_run, u8 buf[], + enum pl330_cond cond, enum dma_transfer_direction direction, + u8 peri) +{ + int off = 0; + + switch (direction) { + case DMA_MEM_TO_MEM: + /* fall through */ + case DMA_DEV_TO_MEM: + off += _emit_ST(dry_run, &buf[off], cond); + break; + + case DMA_MEM_TO_DEV: + if (cond == ALWAYS) { + off += _emit_STP(dry_run, &buf[off], SINGLE, + peri); + off += _emit_STP(dry_run, &buf[off], BURST, + peri); + } else { + off += _emit_STP(dry_run, &buf[off], cond, + peri); + } + break; + + default: + /* this code should be unreachable */ + WARN_ON(1); + break; + } + + return off; +} + +static inline int _ldst_peripheral(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[], - const struct _xfer_spec *pxs, int cyc) + const struct _xfer_spec *pxs, int cyc, + enum pl330_cond cond) { int off = 0; - enum pl330_cond cond; if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) cond = BURST; - else - cond = SINGLE; + /* + * do FLUSHP at beginning to clear any stale dma requests before the + * first WFP. + */ + if (!(pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP)) + off += _emit_FLUSHP(dry_run, &buf[off], pxs->desc->peri); while (cyc--) { off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri); - 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)) - off += _emit_FLUSHP(dry_run, &buf[off], - pxs->desc->peri); + off += _emit_load(dry_run, &buf[off], cond, pxs->desc->rqtype, + pxs->desc->peri); + off += _emit_store(dry_run, &buf[off], cond, pxs->desc->rqtype, + pxs->desc->peri); } return off; @@ -1148,19 +1194,65 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[], const struct _xfer_spec *pxs, int cyc) { int off = 0; + enum pl330_cond cond = BRST_LEN(pxs->ccr) > 1 ? BURST : SINGLE; switch (pxs->desc->rqtype) { case DMA_MEM_TO_DEV: - off += _ldst_memtodev(pl330, dry_run, &buf[off], pxs, cyc); - break; + /* fall through */ case DMA_DEV_TO_MEM: - off += _ldst_devtomem(pl330, dry_run, &buf[off], pxs, cyc); + off += _ldst_peripheral(pl330, dry_run, &buf[off], pxs, cyc, + cond); break; + case DMA_MEM_TO_MEM: off += _ldst_memtomem(dry_run, &buf[off], pxs, cyc); break; + + default: + /* this code should be unreachable */ + WARN_ON(1); + break; + } + + return off; +} + +/* + * transfer dregs with single transfers to peripheral, or a reduced size burst + * for mem-to-mem. + */ +static int _dregs(struct pl330_dmac *pl330, unsigned int dry_run, u8 buf[], + const struct _xfer_spec *pxs, int transfer_length) +{ + int off = 0; + int dregs_ccr; + + if (transfer_length == 0) + return off; + + switch (pxs->desc->rqtype) { + case DMA_MEM_TO_DEV: + /* fall through */ + case DMA_DEV_TO_MEM: + off += _ldst_peripheral(pl330, dry_run, &buf[off], pxs, + transfer_length, SINGLE); + break; + + case DMA_MEM_TO_MEM: + dregs_ccr = pxs->ccr; + dregs_ccr &= ~((0xf << CC_SRCBRSTLEN_SHFT) | + (0xf << CC_DSTBRSTLEN_SHFT)); + dregs_ccr |= (((transfer_length - 1) & 0xf) << + CC_SRCBRSTLEN_SHFT); + dregs_ccr |= (((transfer_length - 1) & 0xf) << + CC_DSTBRSTLEN_SHFT); + off += _emit_MOV(dry_run, &buf[off], CCR, dregs_ccr); + off += _ldst_memtomem(dry_run, &buf[off], pxs, 1); + break; + default: - off += 0x40000000; /* Scare off the Client */ + /* this code should be unreachable */ + WARN_ON(1); break; } @@ -1256,6 +1348,8 @@ static inline int _setup_loops(struct pl330_dmac *pl330, struct pl330_xfer *x = &pxs->desc->px; u32 ccr = pxs->ccr; unsigned long c, bursts = BYTE_TO_BURST(x->bytes, ccr); + int num_dregs = (x->bytes - BURST_TO_BYTE(bursts, ccr)) / + BRST_SIZE(ccr); int off = 0; while (bursts) { @@ -1263,6 +1357,7 @@ static inline int _setup_loops(struct pl330_dmac *pl330, off += _loop(pl330, dry_run, &buf[off], &c, pxs); bursts -= c; } + off += _dregs(pl330, dry_run, &buf[off], pxs, num_dregs); return off; } @@ -1294,7 +1389,6 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run, struct _xfer_spec *pxs) { struct _pl330_req *req = &thrd->req[index]; - struct pl330_xfer *x; u8 *buf = req->mc_cpu; int off = 0; @@ -1303,11 +1397,6 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run, /* DMAMOV CCR, ccr */ off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr); - 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(pl330, dry_run, &buf[off], pxs); /* DMASEV peripheral/event */ @@ -1365,6 +1454,20 @@ static int pl330_submit_req(struct pl330_thread *thrd, u32 ccr; int ret = 0; + switch (desc->rqtype) { + case DMA_MEM_TO_DEV: + break; + + case DMA_DEV_TO_MEM: + break; + + case DMA_MEM_TO_MEM: + break; + + default: + return -ENOTSUPP; + } + if (pl330->state == DYING || pl330->dmac_tbd.reset_chan & (1 << thrd->id)) { dev_info(thrd->dmac->ddma.dev, "%s:%d\n", @@ -2106,6 +2209,18 @@ static bool pl330_prep_slave_fifo(struct dma_pl330_chan *pch, return true; } +static int fixup_burst_len(int max_burst_len, int quirks) +{ + if (quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) + return 1; + else if (max_burst_len > PL330_MAX_BURST) + return PL330_MAX_BURST; + else if (max_burst_len < 1) + return 1; + else + return max_burst_len; +} + static int pl330_config(struct dma_chan *chan, struct dma_slave_config *slave_config) { @@ -2117,15 +2232,15 @@ static int pl330_config(struct dma_chan *chan, pch->fifo_addr = slave_config->dst_addr; if (slave_config->dst_addr_width) pch->burst_sz = __ffs(slave_config->dst_addr_width); - if (slave_config->dst_maxburst) - pch->burst_len = slave_config->dst_maxburst; + pch->burst_len = fixup_burst_len(slave_config->dst_maxburst, + pch->dmac->quirks); } else if (slave_config->direction == DMA_DEV_TO_MEM) { if (slave_config->src_addr) pch->fifo_addr = slave_config->src_addr; if (slave_config->src_addr_width) pch->burst_sz = __ffs(slave_config->src_addr_width); - if (slave_config->src_maxburst) - pch->burst_len = slave_config->src_maxburst; + pch->burst_len = fixup_burst_len(slave_config->src_maxburst, + pch->dmac->quirks); } return 0; @@ -2519,14 +2634,8 @@ static inline int get_burst_len(struct dma_pl330_desc *desc, size_t len) burst_len >>= desc->rqcfg.brst_size; /* src/dst_burst_len can't be more than 16 */ - if (burst_len > 16) - burst_len = 16; - - while (burst_len > 1) { - if (!(len % (burst_len << desc->rqcfg.brst_size))) - break; - burst_len--; - } + if (burst_len > PL330_MAX_BURST) + burst_len = PL330_MAX_BURST; return burst_len; } @@ -2598,7 +2707,7 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic( desc->rqtype = direction; desc->rqcfg.brst_size = pch->burst_sz; - desc->rqcfg.brst_len = 1; + desc->rqcfg.brst_len = pch->burst_len; desc->bytes_requested = period_len; fill_px(&desc->px, dst, src, period_len); @@ -2743,7 +2852,7 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, } desc->rqcfg.brst_size = pch->burst_sz; - desc->rqcfg.brst_len = 1; + desc->rqcfg.brst_len = pch->burst_len; desc->rqtype = direction; desc->bytes_requested = sg_dma_len(sg); } |