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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-28 21:35:15 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-28 21:35:15 +0200 |
commit | 4cb865deec59ef31d966622d1ec87411ae32dfab (patch) | |
tree | e060d515f62e4f334aded38c9079485d50166693 /drivers/dma/at_hdmac.c | |
parent | Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/same... (diff) | |
parent | x86: poll waiting for I/OAT DMA channel status (diff) | |
download | linux-4cb865deec59ef31d966622d1ec87411ae32dfab.tar.xz linux-4cb865deec59ef31d966622d1ec87411ae32dfab.zip |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (33 commits)
x86: poll waiting for I/OAT DMA channel status
maintainers: add dma engine tree details
dmaengine: add TODO items for future work on dma drivers
dmaengine: Add API documentation for slave dma usage
dmaengine/dw_dmac: Update maintainer-ship
dmaengine: move link order
dmaengine/dw_dmac: implement pause and resume in dwc_control
dmaengine/dw_dmac: Replace spin_lock* with irqsave variants and enable submission from callback
dmaengine/dw_dmac: Divide one sg to many desc, if sg len is greater than DWC_MAX_COUNT
dmaengine/dw_dmac: set residue as total len in dwc_tx_status if status is !DMA_SUCCESS
dmaengine/dw_dmac: don't call callback routine in case dmaengine_terminate_all() is called
dmaengine: at_hdmac: pause: no need to wait for FIFO empty
pch_dma: modify pci device table definition
pch_dma: Support new device ML7223 IOH
pch_dma: Support I2S for ML7213 IOH
pch_dma: Fix DMA setting issue
pch_dma: modify for checkpatch
pch_dma: fix dma direction issue for ML7213 IOH video-in
dmaengine: at_hdmac: use descriptor chaining help function
dmaengine: at_hdmac: implement pause and resume in atc_control
...
Fix up trivial conflict in drivers/dma/dw_dmac.c
Diffstat (limited to 'drivers/dma/at_hdmac.c')
-rw-r--r-- | drivers/dma/at_hdmac.c | 376 |
1 files changed, 291 insertions, 85 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 235f53bf494e..36144f88d718 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -37,8 +37,8 @@ #define ATC_DEFAULT_CFG (ATC_FIFOCFG_HALFFIFO) #define ATC_DEFAULT_CTRLA (0) -#define ATC_DEFAULT_CTRLB (ATC_SIF(0) \ - |ATC_DIF(1)) +#define ATC_DEFAULT_CTRLB (ATC_SIF(AT_DMA_MEM_IF) \ + |ATC_DIF(AT_DMA_MEM_IF)) /* * Initial number of descriptors to allocate for each channel. This could @@ -165,6 +165,29 @@ static void atc_desc_put(struct at_dma_chan *atchan, struct at_desc *desc) } /** + * atc_desc_chain - build chain adding a descripor + * @first: address of first descripor of the chain + * @prev: address of previous descripor of the chain + * @desc: descriptor to queue + * + * Called from prep_* functions + */ +static void atc_desc_chain(struct at_desc **first, struct at_desc **prev, + struct at_desc *desc) +{ + if (!(*first)) { + *first = desc; + } else { + /* inform the HW lli about chaining */ + (*prev)->lli.dscr = desc->txd.phys; + /* insert the link descriptor to the LD ring */ + list_add_tail(&desc->desc_node, + &(*first)->tx_list); + } + *prev = desc; +} + +/** * atc_assign_cookie - compute and assign new cookie * @atchan: channel we work on * @desc: descriptor to assign cookie for @@ -237,16 +260,12 @@ static void atc_dostart(struct at_dma_chan *atchan, struct at_desc *first) static void atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) { - dma_async_tx_callback callback; - void *param; struct dma_async_tx_descriptor *txd = &desc->txd; dev_vdbg(chan2dev(&atchan->chan_common), "descriptor %u complete\n", txd->cookie); atchan->completed_cookie = txd->cookie; - callback = txd->callback; - param = txd->callback_param; /* move children to free_list */ list_splice_init(&desc->tx_list, &atchan->free_list); @@ -278,12 +297,19 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) } } - /* - * The API requires that no submissions are done from a - * callback, so we don't need to drop the lock here - */ - if (callback) - callback(param); + /* for cyclic transfers, + * no need to replay callback function while stopping */ + if (!test_bit(ATC_IS_CYCLIC, &atchan->status)) { + dma_async_tx_callback callback = txd->callback; + void *param = txd->callback_param; + + /* + * The API requires that no submissions are done from a + * callback, so we don't need to drop the lock here + */ + if (callback) + callback(param); + } dma_run_dependencies(txd); } @@ -419,6 +445,26 @@ static void atc_handle_error(struct at_dma_chan *atchan) atc_chain_complete(atchan, bad_desc); } +/** + * atc_handle_cyclic - at the end of a period, run callback function + * @atchan: channel used for cyclic operations + * + * Called with atchan->lock held and bh disabled + */ +static void atc_handle_cyclic(struct at_dma_chan *atchan) +{ + struct at_desc *first = atc_first_active(atchan); + struct dma_async_tx_descriptor *txd = &first->txd; + dma_async_tx_callback callback = txd->callback; + void *param = txd->callback_param; + + dev_vdbg(chan2dev(&atchan->chan_common), + "new cyclic period llp 0x%08x\n", + channel_readl(atchan, DSCR)); + + if (callback) + callback(param); +} /*-- IRQ & Tasklet ---------------------------------------------------*/ @@ -426,16 +472,11 @@ static void atc_tasklet(unsigned long data) { struct at_dma_chan *atchan = (struct at_dma_chan *)data; - /* Channel cannot be enabled here */ - if (atc_chan_is_enabled(atchan)) { - dev_err(chan2dev(&atchan->chan_common), - "BUG: channel enabled in tasklet\n"); - return; - } - spin_lock(&atchan->lock); - if (test_and_clear_bit(0, &atchan->error_status)) + if (test_and_clear_bit(ATC_IS_ERROR, &atchan->status)) atc_handle_error(atchan); + else if (test_bit(ATC_IS_CYCLIC, &atchan->status)) + atc_handle_cyclic(atchan); else atc_advance_work(atchan); @@ -464,12 +505,13 @@ static irqreturn_t at_dma_interrupt(int irq, void *dev_id) for (i = 0; i < atdma->dma_common.chancnt; i++) { atchan = &atdma->chan[i]; - if (pending & (AT_DMA_CBTC(i) | AT_DMA_ERR(i))) { + if (pending & (AT_DMA_BTC(i) | AT_DMA_ERR(i))) { if (pending & AT_DMA_ERR(i)) { /* Disable channel on AHB error */ - dma_writel(atdma, CHDR, atchan->mask); + dma_writel(atdma, CHDR, + AT_DMA_RES(i) | atchan->mask); /* Give information to tasklet */ - set_bit(0, &atchan->error_status); + set_bit(ATC_IS_ERROR, &atchan->status); } tasklet_schedule(&atchan->tasklet); ret = IRQ_HANDLED; @@ -549,7 +591,7 @@ atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, } ctrla = ATC_DEFAULT_CTRLA; - ctrlb = ATC_DEFAULT_CTRLB + ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | ATC_SRC_ADDR_MODE_INCR | ATC_DST_ADDR_MODE_INCR | ATC_FC_MEM2MEM; @@ -584,16 +626,7 @@ atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, desc->txd.cookie = 0; - if (!first) { - first = desc; - } else { - /* inform the HW lli about chaining */ - prev->lli.dscr = desc->txd.phys; - /* insert the link descriptor to the LD ring */ - list_add_tail(&desc->desc_node, - &first->tx_list); - } - prev = desc; + atc_desc_chain(&first, &prev, desc); } /* First descriptor of the chain embedds additional information */ @@ -639,7 +672,8 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, struct scatterlist *sg; size_t total_len = 0; - dev_vdbg(chan2dev(chan), "prep_slave_sg: %s f0x%lx\n", + dev_vdbg(chan2dev(chan), "prep_slave_sg (%d): %s f0x%lx\n", + sg_len, direction == DMA_TO_DEVICE ? "TO DEVICE" : "FROM DEVICE", flags); @@ -651,14 +685,15 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, reg_width = atslave->reg_width; ctrla = ATC_DEFAULT_CTRLA | atslave->ctrla; - ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN; + ctrlb = ATC_IEN; switch (direction) { case DMA_TO_DEVICE: ctrla |= ATC_DST_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR - | ATC_FC_MEM2PER; + | ATC_FC_MEM2PER + | ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF); reg = atslave->tx_reg; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; @@ -682,16 +717,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | len >> mem_width; desc->lli.ctrlb = ctrlb; - if (!first) { - first = desc; - } else { - /* inform the HW lli about chaining */ - prev->lli.dscr = desc->txd.phys; - /* insert the link descriptor to the LD ring */ - list_add_tail(&desc->desc_node, - &first->tx_list); - } - prev = desc; + atc_desc_chain(&first, &prev, desc); total_len += len; } break; @@ -699,7 +725,8 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, ctrla |= ATC_SRC_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED - | ATC_FC_PER2MEM; + | ATC_FC_PER2MEM + | ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF); reg = atslave->rx_reg; for_each_sg(sgl, sg, sg_len, i) { @@ -724,16 +751,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, | len >> reg_width; desc->lli.ctrlb = ctrlb; - if (!first) { - first = desc; - } else { - /* inform the HW lli about chaining */ - prev->lli.dscr = desc->txd.phys; - /* insert the link descriptor to the LD ring */ - list_add_tail(&desc->desc_node, - &first->tx_list); - } - prev = desc; + atc_desc_chain(&first, &prev, desc); total_len += len; } break; @@ -759,41 +777,211 @@ err_desc_get: return NULL; } +/** + * atc_dma_cyclic_check_values + * Check for too big/unaligned periods and unaligned DMA buffer + */ +static int +atc_dma_cyclic_check_values(unsigned int reg_width, dma_addr_t buf_addr, + size_t period_len, enum dma_data_direction direction) +{ + if (period_len > (ATC_BTSIZE_MAX << reg_width)) + goto err_out; + if (unlikely(period_len & ((1 << reg_width) - 1))) + goto err_out; + if (unlikely(buf_addr & ((1 << reg_width) - 1))) + goto err_out; + if (unlikely(!(direction & (DMA_TO_DEVICE | DMA_FROM_DEVICE)))) + goto err_out; + + return 0; + +err_out: + return -EINVAL; +} + +/** + * atc_dma_cyclic_fill_desc - Fill one period decriptor + */ +static int +atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc, + unsigned int period_index, dma_addr_t buf_addr, + size_t period_len, enum dma_data_direction direction) +{ + u32 ctrla; + unsigned int reg_width = atslave->reg_width; + + /* prepare common CRTLA value */ + ctrla = ATC_DEFAULT_CTRLA | atslave->ctrla + | ATC_DST_WIDTH(reg_width) + | ATC_SRC_WIDTH(reg_width) + | period_len >> reg_width; + + switch (direction) { + case DMA_TO_DEVICE: + desc->lli.saddr = buf_addr + (period_len * period_index); + desc->lli.daddr = atslave->tx_reg; + desc->lli.ctrla = ctrla; + desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED + | ATC_SRC_ADDR_MODE_INCR + | ATC_FC_MEM2PER + | ATC_SIF(AT_DMA_MEM_IF) + | ATC_DIF(AT_DMA_PER_IF); + break; + + case DMA_FROM_DEVICE: + desc->lli.saddr = atslave->rx_reg; + desc->lli.daddr = buf_addr + (period_len * period_index); + desc->lli.ctrla = ctrla; + desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR + | ATC_SRC_ADDR_MODE_FIXED + | ATC_FC_PER2MEM + | ATC_SIF(AT_DMA_PER_IF) + | ATC_DIF(AT_DMA_MEM_IF); + break; + + default: + return -EINVAL; + } + + return 0; +} + +/** + * atc_prep_dma_cyclic - prepare the cyclic DMA transfer + * @chan: the DMA channel to prepare + * @buf_addr: physical DMA address where the buffer starts + * @buf_len: total number of bytes for the entire buffer + * @period_len: number of bytes for each period + * @direction: transfer direction, to or from device + */ +static struct dma_async_tx_descriptor * +atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_data_direction direction) +{ + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_dma_slave *atslave = chan->private; + struct at_desc *first = NULL; + struct at_desc *prev = NULL; + unsigned long was_cyclic; + unsigned int periods = buf_len / period_len; + unsigned int i; + + dev_vdbg(chan2dev(chan), "prep_dma_cyclic: %s buf@0x%08x - %d (%d/%d)\n", + direction == DMA_TO_DEVICE ? "TO DEVICE" : "FROM DEVICE", + buf_addr, + periods, buf_len, period_len); + + if (unlikely(!atslave || !buf_len || !period_len)) { + dev_dbg(chan2dev(chan), "prep_dma_cyclic: length is zero!\n"); + return NULL; + } + + was_cyclic = test_and_set_bit(ATC_IS_CYCLIC, &atchan->status); + if (was_cyclic) { + dev_dbg(chan2dev(chan), "prep_dma_cyclic: channel in use!\n"); + return NULL; + } + + /* Check for too big/unaligned periods and unaligned DMA buffer */ + if (atc_dma_cyclic_check_values(atslave->reg_width, buf_addr, + period_len, direction)) + goto err_out; + + /* build cyclic linked list */ + for (i = 0; i < periods; i++) { + struct at_desc *desc; + + desc = atc_desc_get(atchan); + if (!desc) + goto err_desc_get; + + if (atc_dma_cyclic_fill_desc(atslave, desc, i, buf_addr, + period_len, direction)) + goto err_desc_get; + + atc_desc_chain(&first, &prev, desc); + } + + /* lets make a cyclic list */ + prev->lli.dscr = first->txd.phys; + + /* First descriptor of the chain embedds additional information */ + first->txd.cookie = -EBUSY; + first->len = buf_len; + + return &first->txd; + +err_desc_get: + dev_err(chan2dev(chan), "not enough descriptors available\n"); + atc_desc_put(atchan, first); +err_out: + clear_bit(ATC_IS_CYCLIC, &atchan->status); + return NULL; +} + + static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - struct at_desc *desc, *_desc; + int chan_id = atchan->chan_common.chan_id; + LIST_HEAD(list); - /* Only supports DMA_TERMINATE_ALL */ - if (cmd != DMA_TERMINATE_ALL) - return -ENXIO; + dev_vdbg(chan2dev(chan), "atc_control (%d)\n", cmd); - /* - * This is only called when something went wrong elsewhere, so - * we don't really care about the data. Just disable the - * channel. We still have to poll the channel enable bit due - * to AHB/HSB limitations. - */ - spin_lock_bh(&atchan->lock); + if (cmd == DMA_PAUSE) { + spin_lock_bh(&atchan->lock); - dma_writel(atdma, CHDR, atchan->mask); + dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id)); + set_bit(ATC_IS_PAUSED, &atchan->status); - /* confirm that this channel is disabled */ - while (dma_readl(atdma, CHSR) & atchan->mask) - cpu_relax(); + spin_unlock_bh(&atchan->lock); + } else if (cmd == DMA_RESUME) { + if (!test_bit(ATC_IS_PAUSED, &atchan->status)) + return 0; - /* active_list entries will end up before queued entries */ - list_splice_init(&atchan->queue, &list); - list_splice_init(&atchan->active_list, &list); + spin_lock_bh(&atchan->lock); - /* Flush all pending and queued descriptors */ - list_for_each_entry_safe(desc, _desc, &list, desc_node) - atc_chain_complete(atchan, desc); + dma_writel(atdma, CHDR, AT_DMA_RES(chan_id)); + clear_bit(ATC_IS_PAUSED, &atchan->status); - spin_unlock_bh(&atchan->lock); + spin_unlock_bh(&atchan->lock); + } else if (cmd == DMA_TERMINATE_ALL) { + struct at_desc *desc, *_desc; + /* + * This is only called when something went wrong elsewhere, so + * we don't really care about the data. Just disable the + * channel. We still have to poll the channel enable bit due + * to AHB/HSB limitations. + */ + spin_lock_bh(&atchan->lock); + + /* disabling channel: must also remove suspend state */ + dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask); + + /* confirm that this channel is disabled */ + while (dma_readl(atdma, CHSR) & atchan->mask) + cpu_relax(); + + /* active_list entries will end up before queued entries */ + list_splice_init(&atchan->queue, &list); + list_splice_init(&atchan->active_list, &list); + + /* Flush all pending and queued descriptors */ + list_for_each_entry_safe(desc, _desc, &list, desc_node) + atc_chain_complete(atchan, desc); + + clear_bit(ATC_IS_PAUSED, &atchan->status); + /* if channel dedicated to cyclic operations, free it */ + clear_bit(ATC_IS_CYCLIC, &atchan->status); + + spin_unlock_bh(&atchan->lock); + } else { + return -ENXIO; + } return 0; } @@ -835,9 +1023,17 @@ atc_tx_status(struct dma_chan *chan, spin_unlock_bh(&atchan->lock); - dma_set_tx_state(txstate, last_complete, last_used, 0); - dev_vdbg(chan2dev(chan), "tx_status: %d (d%d, u%d)\n", - cookie, last_complete ? last_complete : 0, + if (ret != DMA_SUCCESS) + dma_set_tx_state(txstate, last_complete, last_used, + atc_first_active(atchan)->len); + else + dma_set_tx_state(txstate, last_complete, last_used, 0); + + if (test_bit(ATC_IS_PAUSED, &atchan->status)) + ret = DMA_PAUSED; + + dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d (d%d, u%d)\n", + ret, cookie, last_complete ? last_complete : 0, last_used ? last_used : 0); return ret; @@ -853,6 +1049,10 @@ static void atc_issue_pending(struct dma_chan *chan) dev_vdbg(chan2dev(chan), "issue_pending\n"); + /* Not needed for cyclic transfers */ + if (test_bit(ATC_IS_CYCLIC, &atchan->status)) + return; + spin_lock_bh(&atchan->lock); if (!atc_chan_is_enabled(atchan)) { atc_advance_work(atchan); @@ -959,6 +1159,7 @@ static void atc_free_chan_resources(struct dma_chan *chan) } list_splice_init(&atchan->free_list, &list); atchan->descs_allocated = 0; + atchan->status = 0; dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); } @@ -1092,10 +1293,15 @@ static int __init at_dma_probe(struct platform_device *pdev) if (dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask)) atdma->dma_common.device_prep_dma_memcpy = atc_prep_dma_memcpy; - if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) { + if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) atdma->dma_common.device_prep_slave_sg = atc_prep_slave_sg; + + if (dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask)) + atdma->dma_common.device_prep_dma_cyclic = atc_prep_dma_cyclic; + + if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) || + dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask)) atdma->dma_common.device_control = atc_control; - } dma_writel(atdma, EN, AT_DMA_ENABLE); |