Message ID | 1548326680-16454-3-git-send-email-shun-chih.yu@mediatek.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [1/2] dt-bindings: dmaengine: Add MediaTek Command-Queue DMA controller bindings | expand |
On Thu, Jan 24, 2019 at 2:46 AM <shun-chih.yu@mediatek.com> wrote: > > From: Shun-Chih Yu <shun-chih.yu@mediatek.com> > > This patch introduces active_vdec to indicate the virtual descriptor > under processing by the CQDMA dmaengine, and simplify the control logic > by removing redundant queue structure, tasklets, and completion > management. > > Also, wrong residue assignment in mtk_cqdma_tx_status and typos are > fixed. overall changes are good and let code become clear, but it's better to do one thing at a patch instead of mixing all stuff together. > > Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com> > --- > drivers/dma/mediatek/mtk-cqdma.c | 399 ++++++++++---------------------------- > 1 file changed, 98 insertions(+), 301 deletions(-) > > diff --git a/drivers/dma/mediatek/mtk-cqdma.c b/drivers/dma/mediatek/mtk-cqdma.c > index 131f397..387781b 100644 > --- a/drivers/dma/mediatek/mtk-cqdma.c > +++ b/drivers/dma/mediatek/mtk-cqdma.c > @@ -22,6 +22,7 @@ > #include <linux/of_dma.h> > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > +#include <linux/preempt.h> > #include <linux/refcount.h> > #include <linux/slab.h> > > @@ -47,7 +48,6 @@ > #define MTK_CQDMA_SRC 0x1c > #define MTK_CQDMA_DST 0x20 > #define MTK_CQDMA_LEN1 0x24 > -#define MTK_CQDMA_LEN2 0x28 > #define MTK_CQDMA_SRC2 0x60 > #define MTK_CQDMA_DST2 0x64 > > @@ -69,45 +69,32 @@ > * descriptor (CVD) > * @vd: An instance for struct virt_dma_desc > * @len: The total data size device wants to move > - * @residue: The remaining data size device will move > * @dest: The destination address device wants to move to > * @src: The source address device wants to move from > * @ch: The pointer to the corresponding dma channel > - * @node: The lise_head struct to build link-list for VDs > - * @parent: The pointer to the parent CVD > */ > struct mtk_cqdma_vdesc { > struct virt_dma_desc vd; > size_t len; > - size_t residue; > dma_addr_t dest; > dma_addr_t src; > struct dma_chan *ch; > - > - struct list_head node; > - struct mtk_cqdma_vdesc *parent; > }; > > /** > * struct mtk_cqdma_pchan - The struct holding info describing physical > * channel (PC) > - * @queue: Queue for the PDs issued to this PC > + * @active_vdesc: The pointer to the CVD which is under processing > * @base: The mapped register I/O base of this PC > * @irq: The IRQ that this PC are using > * @refcnt: Track how many VCs are using this PC > - * @tasklet: Tasklet for this PC > * @lock: Lock protect agaisting multiple VCs access PC > */ > struct mtk_cqdma_pchan { > - struct list_head queue; > + struct mtk_cqdma_vdesc *active_vdesc; > void __iomem *base; > u32 irq; > - > refcount_t refcnt; > - > - struct tasklet_struct tasklet; > - > - /* lock to protect PC */ > spinlock_t lock; > }; > > @@ -116,14 +103,10 @@ struct mtk_cqdma_pchan { > * channel (VC) > * @vc: An instance for struct virt_dma_chan > * @pc: The pointer to the underlying PC > - * @issue_completion: The wait for all issued descriptors completited > - * @issue_synchronize: Bool indicating channel synchronization starts > */ > struct mtk_cqdma_vchan { > struct virt_dma_chan vc; > struct mtk_cqdma_pchan *pc; > - struct completion issue_completion; > - bool issue_synchronize; > }; > > /** > @@ -168,7 +151,7 @@ static struct device *cqdma2dev(struct mtk_cqdma_device *cqdma) > > static u32 mtk_dma_read(struct mtk_cqdma_pchan *pc, u32 reg) > { > - return readl(pc->base + reg); > + return readl_relaxed(pc->base + reg); that can be moved to separate patch and explains why > } > > static void mtk_dma_write(struct mtk_cqdma_pchan *pc, u32 reg, u32 val) > @@ -202,22 +185,22 @@ static void mtk_cqdma_vdesc_free(struct virt_dma_desc *vd) > kfree(to_cqdma_vdesc(vd)); > } > > -static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc, bool atomic) > +static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc) > { > u32 status = 0; > > - if (!atomic) > + if (!in_task()) if (in_task()) > return readl_poll_timeout(pc->base + MTK_CQDMA_EN, > status, > !(status & MTK_CQDMA_EN_BIT), > MTK_CQDMA_USEC_POLL, > MTK_CQDMA_TIMEOUT_POLL); > - > - return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, > - status, > - !(status & MTK_CQDMA_EN_BIT), > - MTK_CQDMA_USEC_POLL, > - MTK_CQDMA_TIMEOUT_POLL); > + else > + return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, > + status, > + !(status & MTK_CQDMA_EN_BIT), > + MTK_CQDMA_USEC_POLL, > + MTK_CQDMA_TIMEOUT_POLL); > } > > static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) > @@ -225,20 +208,17 @@ static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) > mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); > mtk_dma_clr(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); > > - return mtk_cqdma_poll_engine_done(pc, false); > + return mtk_cqdma_poll_engine_done(pc); > } > > static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > struct mtk_cqdma_vdesc *cvd) > { > - /* wait for the previous transaction done */ > - if (mtk_cqdma_poll_engine_done(pc, true) < 0) > - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma wait transaction timeout\n"); > - > /* warm reset the dma engine for the new transaction */ > mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_WARM_RST_BIT); > - if (mtk_cqdma_poll_engine_done(pc, true) < 0) > - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma warm reset timeout\n"); > + if (mtk_cqdma_poll_engine_done(pc) < 0) > + dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), > + "cqdma warm reset timeout\n"); > > /* setup the source */ > mtk_dma_set(pc, MTK_CQDMA_SRC, cvd->src & MTK_CQDMA_ADDR_LIMIT); > @@ -253,11 +233,12 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT > mtk_dma_set(pc, MTK_CQDMA_DST2, cvd->dest >> MTK_CQDMA_ADDR2_SHFIT); > #else > - mtk_dma_set(pc, MTK_CQDMA_SRC2, 0); > + mtk_dma_set(pc, MTK_CQDMA_DST2, 0); if it is mistakenly coded, it should be moved to separate fixup patch with a tag Fixes: b1f01e48df5a ("dmaengine: mediatek: Add MediaTek Command-Queue DMA controller for MT6765 SoC") > #endif > > /* setup the length */ > - mtk_dma_set(pc, MTK_CQDMA_LEN1, cvd->len); > + mtk_dma_set(pc, MTK_CQDMA_LEN1, (cvd->len < MTK_CQDMA_MAX_LEN) ? > + cvd->len : MTK_CQDMA_MAX_LEN); > > /* start dma engine */ > mtk_dma_set(pc, MTK_CQDMA_EN, MTK_CQDMA_EN_BIT); > @@ -265,30 +246,17 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > > static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) > { > - struct virt_dma_desc *vd, *vd2; > + struct virt_dma_desc *vd; > struct mtk_cqdma_pchan *pc = cvc->pc; > - struct mtk_cqdma_vdesc *cvd; > - bool trigger_engine = false; > > lockdep_assert_held(&cvc->vc.lock); > lockdep_assert_held(&pc->lock); > > - list_for_each_entry_safe(vd, vd2, &cvc->vc.desc_issued, node) { > - /* need to trigger dma engine if PC's queue is empty */ > - if (list_empty(&pc->queue)) > - trigger_engine = true; > - > - cvd = to_cqdma_vdesc(vd); > + vd = vchan_next_desc(&cvc->vc); > > - /* add VD into PC's queue */ > - list_add_tail(&cvd->node, &pc->queue); > - > - /* start the dma engine */ > - if (trigger_engine) > - mtk_cqdma_start(pc, cvd); > - > - /* remove VD from list desc_issued */ > - list_del(&vd->node); > + if (vd && !pc->active_vdesc) { > + pc->active_vdesc = to_cqdma_vdesc(vd); > + mtk_cqdma_start(pc, pc->active_vdesc); > } > } > > @@ -298,100 +266,55 @@ static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) > */ > static bool mtk_cqdma_is_vchan_active(struct mtk_cqdma_vchan *cvc) > { > - struct mtk_cqdma_vdesc *cvd; > - > - list_for_each_entry(cvd, &cvc->pc->queue, node) > - if (cvc == to_cqdma_vchan(cvd->ch)) > - return true; > - > - return false; > + return (!cvc->pc->active_vdesc) ? false : > + (cvc == to_cqdma_vchan(cvc->pc->active_vdesc->ch)); > } > > -/* > - * return the pointer of the CVD that is just consumed by the PC > - */ > -static struct mtk_cqdma_vdesc > -*mtk_cqdma_consume_work_queue(struct mtk_cqdma_pchan *pc) > +static void mtk_cqdma_complete_vdesc(struct mtk_cqdma_pchan *pc) > { > struct mtk_cqdma_vchan *cvc; > - struct mtk_cqdma_vdesc *cvd, *ret = NULL; > - > - /* consume a CVD from PC's queue */ > - cvd = list_first_entry_or_null(&pc->queue, > - struct mtk_cqdma_vdesc, node); > - if (unlikely(!cvd || !cvd->parent)) > - return NULL; > + struct mtk_cqdma_vdesc *cvd; > + struct virt_dma_desc *vd; > + size_t tlen; > > + cvd = pc->active_vdesc; > cvc = to_cqdma_vchan(cvd->ch); > - ret = cvd; > - > - /* update residue of the parent CVD */ > - cvd->parent->residue -= cvd->len; > > - /* delete CVD from PC's queue */ > - list_del(&cvd->node); > + tlen = (cvd->len < MTK_CQDMA_MAX_LEN) ? cvd->len : MTK_CQDMA_MAX_LEN; > + cvd->len -= tlen; > + cvd->src += tlen; > + cvd->dest += tlen; > > spin_lock(&cvc->vc.lock); > > - /* check whether all the child CVDs completed */ > - if (!cvd->parent->residue) { > - /* add the parent VD into list desc_completed */ > - vchan_cookie_complete(&cvd->parent->vd); > - > - /* setup completion if this VC is under synchronization */ > - if (cvc->issue_synchronize && !mtk_cqdma_is_vchan_active(cvc)) { > - complete(&cvc->issue_completion); > - cvc->issue_synchronize = false; > - } > - } > - > - spin_unlock(&cvc->vc.lock); > - > - /* start transaction for next CVD in the queue */ > - cvd = list_first_entry_or_null(&pc->queue, > - struct mtk_cqdma_vdesc, node); > - if (cvd) > - mtk_cqdma_start(pc, cvd); > + /* check whether the VD completed */ > + if (!cvd->len) { > + /* delete VD from desc_issued */ > + list_del(&cvd->vd.node); > > - return ret; > -} > - > -static void mtk_cqdma_tasklet_cb(unsigned long data) > -{ > - struct mtk_cqdma_pchan *pc = (struct mtk_cqdma_pchan *)data; > - struct mtk_cqdma_vdesc *cvd = NULL; > - unsigned long flags; > + /* add the VD into list desc_completed */ > + vchan_cookie_complete(&cvd->vd); > > - spin_lock_irqsave(&pc->lock, flags); > - /* consume the queue */ > - cvd = mtk_cqdma_consume_work_queue(pc); > - spin_unlock_irqrestore(&pc->lock, flags); > - > - /* submit the next CVD */ > - if (cvd) { > - dma_run_dependencies(&cvd->vd.tx); > - > - /* > - * free child CVD after completion. > - * the parent CVD would be freeed with desc_free by user. > - */ > - if (cvd->parent != cvd) > - kfree(cvd); > + /* get the next active VD */ > + vd = vchan_next_desc(&cvc->vc); > + pc->active_vdesc = (!vd) ? NULL : to_cqdma_vdesc(vd); > } > > - /* re-enable interrupt before leaving tasklet */ > - enable_irq(pc->irq); > + /* start the next transaction */ > + if (pc->active_vdesc) > + mtk_cqdma_start(pc, pc->active_vdesc); > + > + spin_unlock(&cvc->vc.lock); > } > > static irqreturn_t mtk_cqdma_irq(int irq, void *devid) > { > struct mtk_cqdma_device *cqdma = devid; > irqreturn_t ret = IRQ_NONE; > - bool schedule_tasklet = false; > u32 i; > > /* clear interrupt flags for each PC */ > - for (i = 0; i < cqdma->dma_channels; ++i, schedule_tasklet = false) { > + for (i = 0; i < cqdma->dma_channels; ++i) { > spin_lock(&cqdma->pc[i]->lock); > if (mtk_dma_read(cqdma->pc[i], > MTK_CQDMA_INT_FLAG) & MTK_CQDMA_INT_FLAG_BIT) { > @@ -399,72 +322,21 @@ static irqreturn_t mtk_cqdma_irq(int irq, void *devid) > mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_FLAG, > MTK_CQDMA_INT_FLAG_BIT); > > - schedule_tasklet = true; > + mtk_cqdma_complete_vdesc(cqdma->pc[i]); > + > ret = IRQ_HANDLED; > } > spin_unlock(&cqdma->pc[i]->lock); > - > - if (schedule_tasklet) { > - /* disable interrupt */ > - disable_irq_nosync(cqdma->pc[i]->irq); > - > - /* schedule the tasklet to handle the transactions */ > - tasklet_schedule(&cqdma->pc[i]->tasklet); > - } > } > > return ret; > } > > -static struct virt_dma_desc *mtk_cqdma_find_active_desc(struct dma_chan *c, > - dma_cookie_t cookie) > -{ > - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > - struct virt_dma_desc *vd; > - unsigned long flags; > - > - spin_lock_irqsave(&cvc->pc->lock, flags); > - list_for_each_entry(vd, &cvc->pc->queue, node) > - if (vd->tx.cookie == cookie) { > - spin_unlock_irqrestore(&cvc->pc->lock, flags); > - return vd; > - } > - spin_unlock_irqrestore(&cvc->pc->lock, flags); > - > - list_for_each_entry(vd, &cvc->vc.desc_issued, node) > - if (vd->tx.cookie == cookie) > - return vd; > - > - return NULL; > -} > - > static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c, > dma_cookie_t cookie, > struct dma_tx_state *txstate) > { > - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > - struct mtk_cqdma_vdesc *cvd; > - struct virt_dma_desc *vd; > - enum dma_status ret; > - unsigned long flags; > - size_t bytes = 0; > - > - ret = dma_cookie_status(c, cookie, txstate); > - if (ret == DMA_COMPLETE || !txstate) > - return ret; > - > - spin_lock_irqsave(&cvc->vc.lock, flags); > - vd = mtk_cqdma_find_active_desc(c, cookie); > - spin_unlock_irqrestore(&cvc->vc.lock, flags); > - > - if (vd) { > - cvd = to_cqdma_vdesc(vd); > - bytes = cvd->residue; > - } > - > - dma_set_residue(txstate, bytes); > - > - return ret; > + return dma_cookie_status(c, cookie, txstate); > } > > static void mtk_cqdma_issue_pending(struct dma_chan *c) > @@ -473,7 +345,7 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) > unsigned long pc_flags; > unsigned long vc_flags; > > - /* acquire PC's lock before VS's lock for lock dependency in tasklet */ > + /* acquire PC's lock before VC's lock for lock dependency in ISR */ > spin_lock_irqsave(&cvc->pc->lock, pc_flags); > spin_lock_irqsave(&cvc->vc.lock, vc_flags); > > @@ -488,124 +360,56 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) > mtk_cqdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, > dma_addr_t src, size_t len, unsigned long flags) > { > - struct mtk_cqdma_vdesc **cvd; > - struct dma_async_tx_descriptor *tx = NULL, *prev_tx = NULL; > - size_t i, tlen, nr_vd; > - > - /* > - * In the case that trsanction length is larger than the > - * DMA engine supports, a single memcpy transaction needs > - * to be separated into several DMA transactions. > - * Each DMA transaction would be described by a CVD, > - * and the first one is referred as the parent CVD, > - * while the others are child CVDs. > - * The parent CVD's tx descriptor is the only tx descriptor > - * returned to the DMA user, and it should not be completed > - * until all the child CVDs completed. > - */ > - nr_vd = DIV_ROUND_UP(len, MTK_CQDMA_MAX_LEN); > - cvd = kcalloc(nr_vd, sizeof(*cvd), GFP_NOWAIT); > + struct mtk_cqdma_vdesc *cvd; > + > + cvd = kzalloc(sizeof(*cvd), GFP_NOWAIT); > if (!cvd) > return NULL; > > - for (i = 0; i < nr_vd; ++i) { > - cvd[i] = kzalloc(sizeof(*cvd[i]), GFP_NOWAIT); > - if (!cvd[i]) { > - for (; i > 0; --i) > - kfree(cvd[i - 1]); > - return NULL; > - } > + /* setup dma channel */ > + cvd->ch = c; > > - /* setup dma channel */ > - cvd[i]->ch = c; > + /* setup sourece, destination, and length */ > + cvd->len = len; > + cvd->src = src; > + cvd->dest = dest; > > - /* setup sourece, destination, and length */ > - tlen = (len > MTK_CQDMA_MAX_LEN) ? MTK_CQDMA_MAX_LEN : len; > - cvd[i]->len = tlen; > - cvd[i]->src = src; > - cvd[i]->dest = dest; > - > - /* setup tx descriptor */ > - tx = vchan_tx_prep(to_virt_chan(c), &cvd[i]->vd, flags); > - tx->next = NULL; > - > - if (!i) { > - cvd[0]->residue = len; > - } else { > - prev_tx->next = tx; > - cvd[i]->residue = tlen; > - } > - > - cvd[i]->parent = cvd[0]; > - > - /* update the src, dest, len, prev_tx for the next CVD */ > - src += tlen; > - dest += tlen; > - len -= tlen; > - prev_tx = tx; > - } > - > - return &cvd[0]->vd.tx; > + return vchan_tx_prep(to_virt_chan(c), &cvd->vd, flags); > } > > -static void mtk_cqdma_free_inactive_desc(struct dma_chan *c) > -{ > - struct virt_dma_chan *vc = to_virt_chan(c); > - unsigned long flags; > - LIST_HEAD(head); > - > - /* > - * set desc_allocated, desc_submitted, > - * and desc_issued as the candicates to be freed > - */ > - spin_lock_irqsave(&vc->lock, flags); > - list_splice_tail_init(&vc->desc_allocated, &head); > - list_splice_tail_init(&vc->desc_submitted, &head); > - list_splice_tail_init(&vc->desc_issued, &head); > - spin_unlock_irqrestore(&vc->lock, flags); > - > - /* free descriptor lists */ > - vchan_dma_desc_free_list(vc, &head); > -} > - > -static void mtk_cqdma_free_active_desc(struct dma_chan *c) > +static int mtk_cqdma_terminate_all(struct dma_chan *c) > { > struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > - bool sync_needed = false; > + struct virt_dma_chan *vc = to_virt_chan(c); > unsigned long pc_flags; > unsigned long vc_flags; > + LIST_HEAD(head); > > - /* acquire PC's lock first due to lock dependency in dma ISR */ > - spin_lock_irqsave(&cvc->pc->lock, pc_flags); > - spin_lock_irqsave(&cvc->vc.lock, vc_flags); > - > - /* synchronization is required if this VC is active */ > - if (mtk_cqdma_is_vchan_active(cvc)) { > - cvc->issue_synchronize = true; > - sync_needed = true; > - } > + do { > + /* acquire PC's lock first due to lock dependency in dma ISR */ > + spin_lock_irqsave(&cvc->pc->lock, pc_flags); > + spin_lock_irqsave(&cvc->vc.lock, vc_flags); > > - spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > - spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > + /* wait for the VC to be inactive */ > + if (mtk_cqdma_is_vchan_active(cvc)) { > + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > + continue; > + } > > - /* waiting for the completion of this VC */ > - if (sync_needed) > - wait_for_completion(&cvc->issue_completion); > + /* get VDs from lists */ > + vchan_get_all_descriptors(vc, &head); > > - /* free all descriptors in list desc_completed */ > - vchan_synchronize(&cvc->vc); > + /* free all the VDs */ > + vchan_dma_desc_free_list(vc, &head); > > - WARN_ONCE(!list_empty(&cvc->vc.desc_completed), > - "Desc pending still in list desc_completed\n"); > -} > + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > > -static int mtk_cqdma_terminate_all(struct dma_chan *c) > -{ > - /* free descriptors not processed yet by hardware */ > - mtk_cqdma_free_inactive_desc(c); > + break; > + } while (1); use wait_for_completion_timeout or something like that instead of polling here to reduce cpu computing waste and to avoid dead-loop risk > > - /* free descriptors being processed by hardware */ > - mtk_cqdma_free_active_desc(c); > + vchan_synchronize(&cvc->vc); > > return 0; > } > @@ -618,7 +422,7 @@ static int mtk_cqdma_alloc_chan_resources(struct dma_chan *c) > u32 i, min_refcnt = U32_MAX, refcnt; > unsigned long flags; > > - /* allocate PC with the minimun refcount */ > + /* allocate PC with the minimum refcount */ > for (i = 0; i < cqdma->dma_channels; ++i) { > refcnt = refcount_read(&cqdma->pc[i]->refcnt); > if (refcnt < min_refcnt) { > @@ -671,8 +475,9 @@ static void mtk_cqdma_free_chan_resources(struct dma_chan *c) > mtk_dma_set(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); > > /* wait for the completion of flush operation */ > - if (mtk_cqdma_poll_engine_done(cvc->pc, false) < 0) > - dev_err(cqdma2dev(to_cqdma_dev(c)), "cqdma flush timeout\n"); > + if (mtk_cqdma_poll_engine_done(cvc->pc) < 0) > + dev_err(cqdma2dev(to_cqdma_dev(c)), > + "cqdma flush timeout\n"); > > /* clear the flush bit and interrupt flag */ > mtk_dma_clr(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); > @@ -787,9 +592,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, > "dma-requests", > &cqdma->dma_requests)) { > - dev_info(&pdev->dev, > - "Using %u as missing dma-requests property\n", > - MTK_CQDMA_NR_VCHANS); > + dev_dbg(&pdev->dev, > + "Using %u as missing dma-requests property\n", > + MTK_CQDMA_NR_VCHANS); > > cqdma->dma_requests = MTK_CQDMA_NR_VCHANS; > } > @@ -797,9 +602,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, > "dma-channels", > &cqdma->dma_channels)) { > - dev_info(&pdev->dev, > - "Using %u as missing dma-channels property\n", > - MTK_CQDMA_NR_PCHANS); > + dev_dbg(&pdev->dev, > + "Using %u as missing dma-channels property\n", > + MTK_CQDMA_NR_PCHANS); > > cqdma->dma_channels = MTK_CQDMA_NR_PCHANS; > } > @@ -816,7 +621,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > if (!cqdma->pc[i]) > return -ENOMEM; > > - INIT_LIST_HEAD(&cqdma->pc[i]->queue); > + cqdma->pc[i]->active_vdesc = NULL; > spin_lock_init(&cqdma->pc[i]->lock); > refcount_set(&cqdma->pc[i]->refcnt, 0); > > @@ -860,7 +665,6 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > vc = &cqdma->vc[i]; > vc->vc.desc_free = mtk_cqdma_vdesc_free; > vchan_init(&vc->vc, dd); > - init_completion(&vc->issue_completion); > } > > err = dma_async_device_register(dd); > @@ -884,12 +688,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, cqdma); > > - /* initialize tasklet for each PC */ > - for (i = 0; i < cqdma->dma_channels; ++i) > - tasklet_init(&cqdma->pc[i]->tasklet, mtk_cqdma_tasklet_cb, > - (unsigned long)cqdma->pc[i]); > - > - dev_info(&pdev->dev, "MediaTek CQDMA driver registered\n"); > + dev_dbg(&pdev->dev, "MediaTek CQDMA driver registered\n"); > > return 0; > > @@ -923,8 +722,6 @@ static int mtk_cqdma_remove(struct platform_device *pdev) > > /* Waits for any pending IRQ handlers to complete */ > synchronize_irq(cqdma->pc[i]->irq); > - > - tasklet_kill(&cqdma->pc[i]->tasklet); > } > > /* disable hardware */ > -- > 1.7.9.5 > > > _______________________________________________ > Linux-mediatek mailing list > Linux-mediatek@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-mediatek
On Thu, 2019-01-24 at 20:19 -0800, Sean Wang wrote: > On Thu, Jan 24, 2019 at 2:46 AM <shun-chih.yu@mediatek.com> wrote: > > > > From: Shun-Chih Yu <shun-chih.yu@mediatek.com> > > > > This patch introduces active_vdec to indicate the virtual descriptor > > under processing by the CQDMA dmaengine, and simplify the control logic > > by removing redundant queue structure, tasklets, and completion > > management. > > > > Also, wrong residue assignment in mtk_cqdma_tx_status and typos are > > fixed. > > overall changes are good and let code become clear, but it's better to > do one thing at a patch instead of mixing all stuff together. > Got it, I would separate this patch. > > > > Signed-off-by: Shun-Chih Yu <shun-chih.yu@mediatek.com> > > --- > > drivers/dma/mediatek/mtk-cqdma.c | 399 ++++++++++---------------------------- > > 1 file changed, 98 insertions(+), 301 deletions(-) > > > > diff --git a/drivers/dma/mediatek/mtk-cqdma.c b/drivers/dma/mediatek/mtk-cqdma.c > > index 131f397..387781b 100644 > > --- a/drivers/dma/mediatek/mtk-cqdma.c > > +++ b/drivers/dma/mediatek/mtk-cqdma.c > > @@ -22,6 +22,7 @@ > > #include <linux/of_dma.h> > > #include <linux/platform_device.h> > > #include <linux/pm_runtime.h> > > +#include <linux/preempt.h> > > #include <linux/refcount.h> > > #include <linux/slab.h> > > > > @@ -47,7 +48,6 @@ > > #define MTK_CQDMA_SRC 0x1c > > #define MTK_CQDMA_DST 0x20 > > #define MTK_CQDMA_LEN1 0x24 > > -#define MTK_CQDMA_LEN2 0x28 > > #define MTK_CQDMA_SRC2 0x60 > > #define MTK_CQDMA_DST2 0x64 > > > > @@ -69,45 +69,32 @@ > > * descriptor (CVD) > > * @vd: An instance for struct virt_dma_desc > > * @len: The total data size device wants to move > > - * @residue: The remaining data size device will move > > * @dest: The destination address device wants to move to > > * @src: The source address device wants to move from > > * @ch: The pointer to the corresponding dma channel > > - * @node: The lise_head struct to build link-list for VDs > > - * @parent: The pointer to the parent CVD > > */ > > struct mtk_cqdma_vdesc { > > struct virt_dma_desc vd; > > size_t len; > > - size_t residue; > > dma_addr_t dest; > > dma_addr_t src; > > struct dma_chan *ch; > > - > > - struct list_head node; > > - struct mtk_cqdma_vdesc *parent; > > }; > > > > /** > > * struct mtk_cqdma_pchan - The struct holding info describing physical > > * channel (PC) > > - * @queue: Queue for the PDs issued to this PC > > + * @active_vdesc: The pointer to the CVD which is under processing > > * @base: The mapped register I/O base of this PC > > * @irq: The IRQ that this PC are using > > * @refcnt: Track how many VCs are using this PC > > - * @tasklet: Tasklet for this PC > > * @lock: Lock protect agaisting multiple VCs access PC > > */ > > struct mtk_cqdma_pchan { > > - struct list_head queue; > > + struct mtk_cqdma_vdesc *active_vdesc; > > void __iomem *base; > > u32 irq; > > - > > refcount_t refcnt; > > - > > - struct tasklet_struct tasklet; > > - > > - /* lock to protect PC */ > > spinlock_t lock; > > }; > > > > @@ -116,14 +103,10 @@ struct mtk_cqdma_pchan { > > * channel (VC) > > * @vc: An instance for struct virt_dma_chan > > * @pc: The pointer to the underlying PC > > - * @issue_completion: The wait for all issued descriptors completited > > - * @issue_synchronize: Bool indicating channel synchronization starts > > */ > > struct mtk_cqdma_vchan { > > struct virt_dma_chan vc; > > struct mtk_cqdma_pchan *pc; > > - struct completion issue_completion; > > - bool issue_synchronize; > > }; > > > > /** > > @@ -168,7 +151,7 @@ static struct device *cqdma2dev(struct mtk_cqdma_device *cqdma) > > > > static u32 mtk_dma_read(struct mtk_cqdma_pchan *pc, u32 reg) > > { > > - return readl(pc->base + reg); > > + return readl_relaxed(pc->base + reg); > > that can be moved to separate patch and explains why > Sure, I would separate this. > > } > > > > static void mtk_dma_write(struct mtk_cqdma_pchan *pc, u32 reg, u32 val) > > @@ -202,22 +185,22 @@ static void mtk_cqdma_vdesc_free(struct virt_dma_desc *vd) > > kfree(to_cqdma_vdesc(vd)); > > } > > > > -static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc, bool atomic) > > +static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc) > > { > > u32 status = 0; > > > > - if (!atomic) > > + if (!in_task()) > > if (in_task()) > This would be fixed in the next revision. > > return readl_poll_timeout(pc->base + MTK_CQDMA_EN, > > status, > > !(status & MTK_CQDMA_EN_BIT), > > MTK_CQDMA_USEC_POLL, > > MTK_CQDMA_TIMEOUT_POLL); > > - > > - return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, > > - status, > > - !(status & MTK_CQDMA_EN_BIT), > > - MTK_CQDMA_USEC_POLL, > > - MTK_CQDMA_TIMEOUT_POLL); > > + else > > + return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, > > + status, > > + !(status & MTK_CQDMA_EN_BIT), > > + MTK_CQDMA_USEC_POLL, > > + MTK_CQDMA_TIMEOUT_POLL); > > } > > > > static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) > > @@ -225,20 +208,17 @@ static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) > > mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); > > mtk_dma_clr(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); > > > > - return mtk_cqdma_poll_engine_done(pc, false); > > + return mtk_cqdma_poll_engine_done(pc); > > } > > > > static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > > struct mtk_cqdma_vdesc *cvd) > > { > > - /* wait for the previous transaction done */ > > - if (mtk_cqdma_poll_engine_done(pc, true) < 0) > > - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma wait transaction timeout\n"); > > - > > /* warm reset the dma engine for the new transaction */ > > mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_WARM_RST_BIT); > > - if (mtk_cqdma_poll_engine_done(pc, true) < 0) > > - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma warm reset timeout\n"); > > + if (mtk_cqdma_poll_engine_done(pc) < 0) > > + dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), > > + "cqdma warm reset timeout\n"); > > > > /* setup the source */ > > mtk_dma_set(pc, MTK_CQDMA_SRC, cvd->src & MTK_CQDMA_ADDR_LIMIT); > > @@ -253,11 +233,12 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > > #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT > > mtk_dma_set(pc, MTK_CQDMA_DST2, cvd->dest >> MTK_CQDMA_ADDR2_SHFIT); > > #else > > - mtk_dma_set(pc, MTK_CQDMA_SRC2, 0); > > + mtk_dma_set(pc, MTK_CQDMA_DST2, 0); > > if it is mistakenly coded, it should be moved to separate fixup patch > with a tag Fixes: b1f01e48df5a ("dmaengine: mediatek: Add MediaTek > Command-Queue DMA controller for MT6765 SoC") Sure,I would separate this fixup. > > #endif > > > > /* setup the length */ > > - mtk_dma_set(pc, MTK_CQDMA_LEN1, cvd->len); > > + mtk_dma_set(pc, MTK_CQDMA_LEN1, (cvd->len < MTK_CQDMA_MAX_LEN) ? > > + cvd->len : MTK_CQDMA_MAX_LEN); > > > > /* start dma engine */ > > mtk_dma_set(pc, MTK_CQDMA_EN, MTK_CQDMA_EN_BIT); > > @@ -265,30 +246,17 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, > > > > static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) > > { > > - struct virt_dma_desc *vd, *vd2; > > + struct virt_dma_desc *vd; > > struct mtk_cqdma_pchan *pc = cvc->pc; > > - struct mtk_cqdma_vdesc *cvd; > > - bool trigger_engine = false; > > > > lockdep_assert_held(&cvc->vc.lock); > > lockdep_assert_held(&pc->lock); > > > > - list_for_each_entry_safe(vd, vd2, &cvc->vc.desc_issued, node) { > > - /* need to trigger dma engine if PC's queue is empty */ > > - if (list_empty(&pc->queue)) > > - trigger_engine = true; > > - > > - cvd = to_cqdma_vdesc(vd); > > + vd = vchan_next_desc(&cvc->vc); > > > > - /* add VD into PC's queue */ > > - list_add_tail(&cvd->node, &pc->queue); > > - > > - /* start the dma engine */ > > - if (trigger_engine) > > - mtk_cqdma_start(pc, cvd); > > - > > - /* remove VD from list desc_issued */ > > - list_del(&vd->node); > > + if (vd && !pc->active_vdesc) { > > + pc->active_vdesc = to_cqdma_vdesc(vd); > > + mtk_cqdma_start(pc, pc->active_vdesc); > > } > > } > > > > @@ -298,100 +266,55 @@ static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) > > */ > > static bool mtk_cqdma_is_vchan_active(struct mtk_cqdma_vchan *cvc) > > { > > - struct mtk_cqdma_vdesc *cvd; > > - > > - list_for_each_entry(cvd, &cvc->pc->queue, node) > > - if (cvc == to_cqdma_vchan(cvd->ch)) > > - return true; > > - > > - return false; > > + return (!cvc->pc->active_vdesc) ? false : > > + (cvc == to_cqdma_vchan(cvc->pc->active_vdesc->ch)); > > } > > > > -/* > > - * return the pointer of the CVD that is just consumed by the PC > > - */ > > -static struct mtk_cqdma_vdesc > > -*mtk_cqdma_consume_work_queue(struct mtk_cqdma_pchan *pc) > > +static void mtk_cqdma_complete_vdesc(struct mtk_cqdma_pchan *pc) > > { > > struct mtk_cqdma_vchan *cvc; > > - struct mtk_cqdma_vdesc *cvd, *ret = NULL; > > - > > - /* consume a CVD from PC's queue */ > > - cvd = list_first_entry_or_null(&pc->queue, > > - struct mtk_cqdma_vdesc, node); > > - if (unlikely(!cvd || !cvd->parent)) > > - return NULL; > > + struct mtk_cqdma_vdesc *cvd; > > + struct virt_dma_desc *vd; > > + size_t tlen; > > > > + cvd = pc->active_vdesc; > > cvc = to_cqdma_vchan(cvd->ch); > > - ret = cvd; > > - > > - /* update residue of the parent CVD */ > > - cvd->parent->residue -= cvd->len; > > > > - /* delete CVD from PC's queue */ > > - list_del(&cvd->node); > > + tlen = (cvd->len < MTK_CQDMA_MAX_LEN) ? cvd->len : MTK_CQDMA_MAX_LEN; > > + cvd->len -= tlen; > > + cvd->src += tlen; > > + cvd->dest += tlen; > > > > spin_lock(&cvc->vc.lock); > > > > - /* check whether all the child CVDs completed */ > > - if (!cvd->parent->residue) { > > - /* add the parent VD into list desc_completed */ > > - vchan_cookie_complete(&cvd->parent->vd); > > - > > - /* setup completion if this VC is under synchronization */ > > - if (cvc->issue_synchronize && !mtk_cqdma_is_vchan_active(cvc)) { > > - complete(&cvc->issue_completion); > > - cvc->issue_synchronize = false; > > - } > > - } > > - > > - spin_unlock(&cvc->vc.lock); > > - > > - /* start transaction for next CVD in the queue */ > > - cvd = list_first_entry_or_null(&pc->queue, > > - struct mtk_cqdma_vdesc, node); > > - if (cvd) > > - mtk_cqdma_start(pc, cvd); > > + /* check whether the VD completed */ > > + if (!cvd->len) { > > + /* delete VD from desc_issued */ > > + list_del(&cvd->vd.node); > > > > - return ret; > > -} > > - > > -static void mtk_cqdma_tasklet_cb(unsigned long data) > > -{ > > - struct mtk_cqdma_pchan *pc = (struct mtk_cqdma_pchan *)data; > > - struct mtk_cqdma_vdesc *cvd = NULL; > > - unsigned long flags; > > + /* add the VD into list desc_completed */ > > + vchan_cookie_complete(&cvd->vd); > > > > - spin_lock_irqsave(&pc->lock, flags); > > - /* consume the queue */ > > - cvd = mtk_cqdma_consume_work_queue(pc); > > - spin_unlock_irqrestore(&pc->lock, flags); > > - > > - /* submit the next CVD */ > > - if (cvd) { > > - dma_run_dependencies(&cvd->vd.tx); > > - > > - /* > > - * free child CVD after completion. > > - * the parent CVD would be freeed with desc_free by user. > > - */ > > - if (cvd->parent != cvd) > > - kfree(cvd); > > + /* get the next active VD */ > > + vd = vchan_next_desc(&cvc->vc); > > + pc->active_vdesc = (!vd) ? NULL : to_cqdma_vdesc(vd); > > } > > > > - /* re-enable interrupt before leaving tasklet */ > > - enable_irq(pc->irq); > > + /* start the next transaction */ > > + if (pc->active_vdesc) > > + mtk_cqdma_start(pc, pc->active_vdesc); > > + > > + spin_unlock(&cvc->vc.lock); > > } > > > > static irqreturn_t mtk_cqdma_irq(int irq, void *devid) > > { > > struct mtk_cqdma_device *cqdma = devid; > > irqreturn_t ret = IRQ_NONE; > > - bool schedule_tasklet = false; > > u32 i; > > > > /* clear interrupt flags for each PC */ > > - for (i = 0; i < cqdma->dma_channels; ++i, schedule_tasklet = false) { > > + for (i = 0; i < cqdma->dma_channels; ++i) { > > spin_lock(&cqdma->pc[i]->lock); > > if (mtk_dma_read(cqdma->pc[i], > > MTK_CQDMA_INT_FLAG) & MTK_CQDMA_INT_FLAG_BIT) { > > @@ -399,72 +322,21 @@ static irqreturn_t mtk_cqdma_irq(int irq, void *devid) > > mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_FLAG, > > MTK_CQDMA_INT_FLAG_BIT); > > > > - schedule_tasklet = true; > > + mtk_cqdma_complete_vdesc(cqdma->pc[i]); > > + > > ret = IRQ_HANDLED; > > } > > spin_unlock(&cqdma->pc[i]->lock); > > - > > - if (schedule_tasklet) { > > - /* disable interrupt */ > > - disable_irq_nosync(cqdma->pc[i]->irq); > > - > > - /* schedule the tasklet to handle the transactions */ > > - tasklet_schedule(&cqdma->pc[i]->tasklet); > > - } > > } > > > > return ret; > > } > > > > -static struct virt_dma_desc *mtk_cqdma_find_active_desc(struct dma_chan *c, > > - dma_cookie_t cookie) > > -{ > > - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > > - struct virt_dma_desc *vd; > > - unsigned long flags; > > - > > - spin_lock_irqsave(&cvc->pc->lock, flags); > > - list_for_each_entry(vd, &cvc->pc->queue, node) > > - if (vd->tx.cookie == cookie) { > > - spin_unlock_irqrestore(&cvc->pc->lock, flags); > > - return vd; > > - } > > - spin_unlock_irqrestore(&cvc->pc->lock, flags); > > - > > - list_for_each_entry(vd, &cvc->vc.desc_issued, node) > > - if (vd->tx.cookie == cookie) > > - return vd; > > - > > - return NULL; > > -} > > - > > static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c, > > dma_cookie_t cookie, > > struct dma_tx_state *txstate) > > { > > - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > > - struct mtk_cqdma_vdesc *cvd; > > - struct virt_dma_desc *vd; > > - enum dma_status ret; > > - unsigned long flags; > > - size_t bytes = 0; > > - > > - ret = dma_cookie_status(c, cookie, txstate); > > - if (ret == DMA_COMPLETE || !txstate) > > - return ret; > > - > > - spin_lock_irqsave(&cvc->vc.lock, flags); > > - vd = mtk_cqdma_find_active_desc(c, cookie); > > - spin_unlock_irqrestore(&cvc->vc.lock, flags); > > - > > - if (vd) { > > - cvd = to_cqdma_vdesc(vd); > > - bytes = cvd->residue; > > - } > > - > > - dma_set_residue(txstate, bytes); > > - > > - return ret; > > + return dma_cookie_status(c, cookie, txstate); > > } > > > > static void mtk_cqdma_issue_pending(struct dma_chan *c) > > @@ -473,7 +345,7 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) > > unsigned long pc_flags; > > unsigned long vc_flags; > > > > - /* acquire PC's lock before VS's lock for lock dependency in tasklet */ > > + /* acquire PC's lock before VC's lock for lock dependency in ISR */ > > spin_lock_irqsave(&cvc->pc->lock, pc_flags); > > spin_lock_irqsave(&cvc->vc.lock, vc_flags); > > > > @@ -488,124 +360,56 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) > > mtk_cqdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, > > dma_addr_t src, size_t len, unsigned long flags) > > { > > - struct mtk_cqdma_vdesc **cvd; > > - struct dma_async_tx_descriptor *tx = NULL, *prev_tx = NULL; > > - size_t i, tlen, nr_vd; > > - > > - /* > > - * In the case that trsanction length is larger than the > > - * DMA engine supports, a single memcpy transaction needs > > - * to be separated into several DMA transactions. > > - * Each DMA transaction would be described by a CVD, > > - * and the first one is referred as the parent CVD, > > - * while the others are child CVDs. > > - * The parent CVD's tx descriptor is the only tx descriptor > > - * returned to the DMA user, and it should not be completed > > - * until all the child CVDs completed. > > - */ > > - nr_vd = DIV_ROUND_UP(len, MTK_CQDMA_MAX_LEN); > > - cvd = kcalloc(nr_vd, sizeof(*cvd), GFP_NOWAIT); > > + struct mtk_cqdma_vdesc *cvd; > > + > > + cvd = kzalloc(sizeof(*cvd), GFP_NOWAIT); > > if (!cvd) > > return NULL; > > > > - for (i = 0; i < nr_vd; ++i) { > > - cvd[i] = kzalloc(sizeof(*cvd[i]), GFP_NOWAIT); > > - if (!cvd[i]) { > > - for (; i > 0; --i) > > - kfree(cvd[i - 1]); > > - return NULL; > > - } > > + /* setup dma channel */ > > + cvd->ch = c; > > > > - /* setup dma channel */ > > - cvd[i]->ch = c; > > + /* setup sourece, destination, and length */ > > + cvd->len = len; > > + cvd->src = src; > > + cvd->dest = dest; > > > > - /* setup sourece, destination, and length */ > > - tlen = (len > MTK_CQDMA_MAX_LEN) ? MTK_CQDMA_MAX_LEN : len; > > - cvd[i]->len = tlen; > > - cvd[i]->src = src; > > - cvd[i]->dest = dest; > > - > > - /* setup tx descriptor */ > > - tx = vchan_tx_prep(to_virt_chan(c), &cvd[i]->vd, flags); > > - tx->next = NULL; > > - > > - if (!i) { > > - cvd[0]->residue = len; > > - } else { > > - prev_tx->next = tx; > > - cvd[i]->residue = tlen; > > - } > > - > > - cvd[i]->parent = cvd[0]; > > - > > - /* update the src, dest, len, prev_tx for the next CVD */ > > - src += tlen; > > - dest += tlen; > > - len -= tlen; > > - prev_tx = tx; > > - } > > - > > - return &cvd[0]->vd.tx; > > + return vchan_tx_prep(to_virt_chan(c), &cvd->vd, flags); > > } > > > > -static void mtk_cqdma_free_inactive_desc(struct dma_chan *c) > > -{ > > - struct virt_dma_chan *vc = to_virt_chan(c); > > - unsigned long flags; > > - LIST_HEAD(head); > > - > > - /* > > - * set desc_allocated, desc_submitted, > > - * and desc_issued as the candicates to be freed > > - */ > > - spin_lock_irqsave(&vc->lock, flags); > > - list_splice_tail_init(&vc->desc_allocated, &head); > > - list_splice_tail_init(&vc->desc_submitted, &head); > > - list_splice_tail_init(&vc->desc_issued, &head); > > - spin_unlock_irqrestore(&vc->lock, flags); > > - > > - /* free descriptor lists */ > > - vchan_dma_desc_free_list(vc, &head); > > -} > > - > > -static void mtk_cqdma_free_active_desc(struct dma_chan *c) > > +static int mtk_cqdma_terminate_all(struct dma_chan *c) > > { > > struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); > > - bool sync_needed = false; > > + struct virt_dma_chan *vc = to_virt_chan(c); > > unsigned long pc_flags; > > unsigned long vc_flags; > > + LIST_HEAD(head); > > > > - /* acquire PC's lock first due to lock dependency in dma ISR */ > > - spin_lock_irqsave(&cvc->pc->lock, pc_flags); > > - spin_lock_irqsave(&cvc->vc.lock, vc_flags); > > - > > - /* synchronization is required if this VC is active */ > > - if (mtk_cqdma_is_vchan_active(cvc)) { > > - cvc->issue_synchronize = true; > > - sync_needed = true; > > - } > > + do { > > + /* acquire PC's lock first due to lock dependency in dma ISR */ > > + spin_lock_irqsave(&cvc->pc->lock, pc_flags); > > + spin_lock_irqsave(&cvc->vc.lock, vc_flags); > > > > - spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > > - spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > > + /* wait for the VC to be inactive */ > > + if (mtk_cqdma_is_vchan_active(cvc)) { > > + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > > + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > > + continue; > > + } > > > > - /* waiting for the completion of this VC */ > > - if (sync_needed) > > - wait_for_completion(&cvc->issue_completion); > > + /* get VDs from lists */ > > + vchan_get_all_descriptors(vc, &head); > > > > - /* free all descriptors in list desc_completed */ > > - vchan_synchronize(&cvc->vc); > > + /* free all the VDs */ > > + vchan_dma_desc_free_list(vc, &head); > > > > - WARN_ONCE(!list_empty(&cvc->vc.desc_completed), > > - "Desc pending still in list desc_completed\n"); > > -} > > + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); > > + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); > > > > -static int mtk_cqdma_terminate_all(struct dma_chan *c) > > -{ > > - /* free descriptors not processed yet by hardware */ > > - mtk_cqdma_free_inactive_desc(c); > > + break; > > + } while (1); > > use wait_for_completion_timeout or something like that instead of > polling here to reduce cpu computing waste and to avoid dead-loop risk Sure, I would drop the infinite polling to make this loop more robust. > > > > - /* free descriptors being processed by hardware */ > > - mtk_cqdma_free_active_desc(c); > > + vchan_synchronize(&cvc->vc); > > > > return 0; > > } > > @@ -618,7 +422,7 @@ static int mtk_cqdma_alloc_chan_resources(struct dma_chan *c) > > u32 i, min_refcnt = U32_MAX, refcnt; > > unsigned long flags; > > > > - /* allocate PC with the minimun refcount */ > > + /* allocate PC with the minimum refcount */ > > for (i = 0; i < cqdma->dma_channels; ++i) { > > refcnt = refcount_read(&cqdma->pc[i]->refcnt); > > if (refcnt < min_refcnt) { > > @@ -671,8 +475,9 @@ static void mtk_cqdma_free_chan_resources(struct dma_chan *c) > > mtk_dma_set(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); > > > > /* wait for the completion of flush operation */ > > - if (mtk_cqdma_poll_engine_done(cvc->pc, false) < 0) > > - dev_err(cqdma2dev(to_cqdma_dev(c)), "cqdma flush timeout\n"); > > + if (mtk_cqdma_poll_engine_done(cvc->pc) < 0) > > + dev_err(cqdma2dev(to_cqdma_dev(c)), > > + "cqdma flush timeout\n"); > > > > /* clear the flush bit and interrupt flag */ > > mtk_dma_clr(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); > > @@ -787,9 +592,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, > > "dma-requests", > > &cqdma->dma_requests)) { > > - dev_info(&pdev->dev, > > - "Using %u as missing dma-requests property\n", > > - MTK_CQDMA_NR_VCHANS); > > + dev_dbg(&pdev->dev, > > + "Using %u as missing dma-requests property\n", > > + MTK_CQDMA_NR_VCHANS); > > > > cqdma->dma_requests = MTK_CQDMA_NR_VCHANS; > > } > > @@ -797,9 +602,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, > > "dma-channels", > > &cqdma->dma_channels)) { > > - dev_info(&pdev->dev, > > - "Using %u as missing dma-channels property\n", > > - MTK_CQDMA_NR_PCHANS); > > + dev_dbg(&pdev->dev, > > + "Using %u as missing dma-channels property\n", > > + MTK_CQDMA_NR_PCHANS); > > > > cqdma->dma_channels = MTK_CQDMA_NR_PCHANS; > > } > > @@ -816,7 +621,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > if (!cqdma->pc[i]) > > return -ENOMEM; > > > > - INIT_LIST_HEAD(&cqdma->pc[i]->queue); > > + cqdma->pc[i]->active_vdesc = NULL; > > spin_lock_init(&cqdma->pc[i]->lock); > > refcount_set(&cqdma->pc[i]->refcnt, 0); > > > > @@ -860,7 +665,6 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > vc = &cqdma->vc[i]; > > vc->vc.desc_free = mtk_cqdma_vdesc_free; > > vchan_init(&vc->vc, dd); > > - init_completion(&vc->issue_completion); > > } > > > > err = dma_async_device_register(dd); > > @@ -884,12 +688,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) > > > > platform_set_drvdata(pdev, cqdma); > > > > - /* initialize tasklet for each PC */ > > - for (i = 0; i < cqdma->dma_channels; ++i) > > - tasklet_init(&cqdma->pc[i]->tasklet, mtk_cqdma_tasklet_cb, > > - (unsigned long)cqdma->pc[i]); > > - > > - dev_info(&pdev->dev, "MediaTek CQDMA driver registered\n"); > > + dev_dbg(&pdev->dev, "MediaTek CQDMA driver registered\n"); > > > > return 0; > > > > @@ -923,8 +722,6 @@ static int mtk_cqdma_remove(struct platform_device *pdev) > > > > /* Waits for any pending IRQ handlers to complete */ > > synchronize_irq(cqdma->pc[i]->irq); > > - > > - tasklet_kill(&cqdma->pc[i]->tasklet); > > } > > > > /* disable hardware */ > > -- > > 1.7.9.5 > > > > > > _______________________________________________ > > Linux-mediatek mailing list > > Linux-mediatek@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-mediatek > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/drivers/dma/mediatek/mtk-cqdma.c b/drivers/dma/mediatek/mtk-cqdma.c index 131f397..387781b 100644 --- a/drivers/dma/mediatek/mtk-cqdma.c +++ b/drivers/dma/mediatek/mtk-cqdma.c @@ -22,6 +22,7 @@ #include <linux/of_dma.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/preempt.h> #include <linux/refcount.h> #include <linux/slab.h> @@ -47,7 +48,6 @@ #define MTK_CQDMA_SRC 0x1c #define MTK_CQDMA_DST 0x20 #define MTK_CQDMA_LEN1 0x24 -#define MTK_CQDMA_LEN2 0x28 #define MTK_CQDMA_SRC2 0x60 #define MTK_CQDMA_DST2 0x64 @@ -69,45 +69,32 @@ * descriptor (CVD) * @vd: An instance for struct virt_dma_desc * @len: The total data size device wants to move - * @residue: The remaining data size device will move * @dest: The destination address device wants to move to * @src: The source address device wants to move from * @ch: The pointer to the corresponding dma channel - * @node: The lise_head struct to build link-list for VDs - * @parent: The pointer to the parent CVD */ struct mtk_cqdma_vdesc { struct virt_dma_desc vd; size_t len; - size_t residue; dma_addr_t dest; dma_addr_t src; struct dma_chan *ch; - - struct list_head node; - struct mtk_cqdma_vdesc *parent; }; /** * struct mtk_cqdma_pchan - The struct holding info describing physical * channel (PC) - * @queue: Queue for the PDs issued to this PC + * @active_vdesc: The pointer to the CVD which is under processing * @base: The mapped register I/O base of this PC * @irq: The IRQ that this PC are using * @refcnt: Track how many VCs are using this PC - * @tasklet: Tasklet for this PC * @lock: Lock protect agaisting multiple VCs access PC */ struct mtk_cqdma_pchan { - struct list_head queue; + struct mtk_cqdma_vdesc *active_vdesc; void __iomem *base; u32 irq; - refcount_t refcnt; - - struct tasklet_struct tasklet; - - /* lock to protect PC */ spinlock_t lock; }; @@ -116,14 +103,10 @@ struct mtk_cqdma_pchan { * channel (VC) * @vc: An instance for struct virt_dma_chan * @pc: The pointer to the underlying PC - * @issue_completion: The wait for all issued descriptors completited - * @issue_synchronize: Bool indicating channel synchronization starts */ struct mtk_cqdma_vchan { struct virt_dma_chan vc; struct mtk_cqdma_pchan *pc; - struct completion issue_completion; - bool issue_synchronize; }; /** @@ -168,7 +151,7 @@ static struct device *cqdma2dev(struct mtk_cqdma_device *cqdma) static u32 mtk_dma_read(struct mtk_cqdma_pchan *pc, u32 reg) { - return readl(pc->base + reg); + return readl_relaxed(pc->base + reg); } static void mtk_dma_write(struct mtk_cqdma_pchan *pc, u32 reg, u32 val) @@ -202,22 +185,22 @@ static void mtk_cqdma_vdesc_free(struct virt_dma_desc *vd) kfree(to_cqdma_vdesc(vd)); } -static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc, bool atomic) +static int mtk_cqdma_poll_engine_done(struct mtk_cqdma_pchan *pc) { u32 status = 0; - if (!atomic) + if (!in_task()) return readl_poll_timeout(pc->base + MTK_CQDMA_EN, status, !(status & MTK_CQDMA_EN_BIT), MTK_CQDMA_USEC_POLL, MTK_CQDMA_TIMEOUT_POLL); - - return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, - status, - !(status & MTK_CQDMA_EN_BIT), - MTK_CQDMA_USEC_POLL, - MTK_CQDMA_TIMEOUT_POLL); + else + return readl_poll_timeout_atomic(pc->base + MTK_CQDMA_EN, + status, + !(status & MTK_CQDMA_EN_BIT), + MTK_CQDMA_USEC_POLL, + MTK_CQDMA_TIMEOUT_POLL); } static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) @@ -225,20 +208,17 @@ static int mtk_cqdma_hard_reset(struct mtk_cqdma_pchan *pc) mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); mtk_dma_clr(pc, MTK_CQDMA_RESET, MTK_CQDMA_HARD_RST_BIT); - return mtk_cqdma_poll_engine_done(pc, false); + return mtk_cqdma_poll_engine_done(pc); } static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, struct mtk_cqdma_vdesc *cvd) { - /* wait for the previous transaction done */ - if (mtk_cqdma_poll_engine_done(pc, true) < 0) - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma wait transaction timeout\n"); - /* warm reset the dma engine for the new transaction */ mtk_dma_set(pc, MTK_CQDMA_RESET, MTK_CQDMA_WARM_RST_BIT); - if (mtk_cqdma_poll_engine_done(pc, true) < 0) - dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), "cqdma warm reset timeout\n"); + if (mtk_cqdma_poll_engine_done(pc) < 0) + dev_err(cqdma2dev(to_cqdma_dev(cvd->ch)), + "cqdma warm reset timeout\n"); /* setup the source */ mtk_dma_set(pc, MTK_CQDMA_SRC, cvd->src & MTK_CQDMA_ADDR_LIMIT); @@ -253,11 +233,12 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT mtk_dma_set(pc, MTK_CQDMA_DST2, cvd->dest >> MTK_CQDMA_ADDR2_SHFIT); #else - mtk_dma_set(pc, MTK_CQDMA_SRC2, 0); + mtk_dma_set(pc, MTK_CQDMA_DST2, 0); #endif /* setup the length */ - mtk_dma_set(pc, MTK_CQDMA_LEN1, cvd->len); + mtk_dma_set(pc, MTK_CQDMA_LEN1, (cvd->len < MTK_CQDMA_MAX_LEN) ? + cvd->len : MTK_CQDMA_MAX_LEN); /* start dma engine */ mtk_dma_set(pc, MTK_CQDMA_EN, MTK_CQDMA_EN_BIT); @@ -265,30 +246,17 @@ static void mtk_cqdma_start(struct mtk_cqdma_pchan *pc, static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) { - struct virt_dma_desc *vd, *vd2; + struct virt_dma_desc *vd; struct mtk_cqdma_pchan *pc = cvc->pc; - struct mtk_cqdma_vdesc *cvd; - bool trigger_engine = false; lockdep_assert_held(&cvc->vc.lock); lockdep_assert_held(&pc->lock); - list_for_each_entry_safe(vd, vd2, &cvc->vc.desc_issued, node) { - /* need to trigger dma engine if PC's queue is empty */ - if (list_empty(&pc->queue)) - trigger_engine = true; - - cvd = to_cqdma_vdesc(vd); + vd = vchan_next_desc(&cvc->vc); - /* add VD into PC's queue */ - list_add_tail(&cvd->node, &pc->queue); - - /* start the dma engine */ - if (trigger_engine) - mtk_cqdma_start(pc, cvd); - - /* remove VD from list desc_issued */ - list_del(&vd->node); + if (vd && !pc->active_vdesc) { + pc->active_vdesc = to_cqdma_vdesc(vd); + mtk_cqdma_start(pc, pc->active_vdesc); } } @@ -298,100 +266,55 @@ static void mtk_cqdma_issue_vchan_pending(struct mtk_cqdma_vchan *cvc) */ static bool mtk_cqdma_is_vchan_active(struct mtk_cqdma_vchan *cvc) { - struct mtk_cqdma_vdesc *cvd; - - list_for_each_entry(cvd, &cvc->pc->queue, node) - if (cvc == to_cqdma_vchan(cvd->ch)) - return true; - - return false; + return (!cvc->pc->active_vdesc) ? false : + (cvc == to_cqdma_vchan(cvc->pc->active_vdesc->ch)); } -/* - * return the pointer of the CVD that is just consumed by the PC - */ -static struct mtk_cqdma_vdesc -*mtk_cqdma_consume_work_queue(struct mtk_cqdma_pchan *pc) +static void mtk_cqdma_complete_vdesc(struct mtk_cqdma_pchan *pc) { struct mtk_cqdma_vchan *cvc; - struct mtk_cqdma_vdesc *cvd, *ret = NULL; - - /* consume a CVD from PC's queue */ - cvd = list_first_entry_or_null(&pc->queue, - struct mtk_cqdma_vdesc, node); - if (unlikely(!cvd || !cvd->parent)) - return NULL; + struct mtk_cqdma_vdesc *cvd; + struct virt_dma_desc *vd; + size_t tlen; + cvd = pc->active_vdesc; cvc = to_cqdma_vchan(cvd->ch); - ret = cvd; - - /* update residue of the parent CVD */ - cvd->parent->residue -= cvd->len; - /* delete CVD from PC's queue */ - list_del(&cvd->node); + tlen = (cvd->len < MTK_CQDMA_MAX_LEN) ? cvd->len : MTK_CQDMA_MAX_LEN; + cvd->len -= tlen; + cvd->src += tlen; + cvd->dest += tlen; spin_lock(&cvc->vc.lock); - /* check whether all the child CVDs completed */ - if (!cvd->parent->residue) { - /* add the parent VD into list desc_completed */ - vchan_cookie_complete(&cvd->parent->vd); - - /* setup completion if this VC is under synchronization */ - if (cvc->issue_synchronize && !mtk_cqdma_is_vchan_active(cvc)) { - complete(&cvc->issue_completion); - cvc->issue_synchronize = false; - } - } - - spin_unlock(&cvc->vc.lock); - - /* start transaction for next CVD in the queue */ - cvd = list_first_entry_or_null(&pc->queue, - struct mtk_cqdma_vdesc, node); - if (cvd) - mtk_cqdma_start(pc, cvd); + /* check whether the VD completed */ + if (!cvd->len) { + /* delete VD from desc_issued */ + list_del(&cvd->vd.node); - return ret; -} - -static void mtk_cqdma_tasklet_cb(unsigned long data) -{ - struct mtk_cqdma_pchan *pc = (struct mtk_cqdma_pchan *)data; - struct mtk_cqdma_vdesc *cvd = NULL; - unsigned long flags; + /* add the VD into list desc_completed */ + vchan_cookie_complete(&cvd->vd); - spin_lock_irqsave(&pc->lock, flags); - /* consume the queue */ - cvd = mtk_cqdma_consume_work_queue(pc); - spin_unlock_irqrestore(&pc->lock, flags); - - /* submit the next CVD */ - if (cvd) { - dma_run_dependencies(&cvd->vd.tx); - - /* - * free child CVD after completion. - * the parent CVD would be freeed with desc_free by user. - */ - if (cvd->parent != cvd) - kfree(cvd); + /* get the next active VD */ + vd = vchan_next_desc(&cvc->vc); + pc->active_vdesc = (!vd) ? NULL : to_cqdma_vdesc(vd); } - /* re-enable interrupt before leaving tasklet */ - enable_irq(pc->irq); + /* start the next transaction */ + if (pc->active_vdesc) + mtk_cqdma_start(pc, pc->active_vdesc); + + spin_unlock(&cvc->vc.lock); } static irqreturn_t mtk_cqdma_irq(int irq, void *devid) { struct mtk_cqdma_device *cqdma = devid; irqreturn_t ret = IRQ_NONE; - bool schedule_tasklet = false; u32 i; /* clear interrupt flags for each PC */ - for (i = 0; i < cqdma->dma_channels; ++i, schedule_tasklet = false) { + for (i = 0; i < cqdma->dma_channels; ++i) { spin_lock(&cqdma->pc[i]->lock); if (mtk_dma_read(cqdma->pc[i], MTK_CQDMA_INT_FLAG) & MTK_CQDMA_INT_FLAG_BIT) { @@ -399,72 +322,21 @@ static irqreturn_t mtk_cqdma_irq(int irq, void *devid) mtk_dma_clr(cqdma->pc[i], MTK_CQDMA_INT_FLAG, MTK_CQDMA_INT_FLAG_BIT); - schedule_tasklet = true; + mtk_cqdma_complete_vdesc(cqdma->pc[i]); + ret = IRQ_HANDLED; } spin_unlock(&cqdma->pc[i]->lock); - - if (schedule_tasklet) { - /* disable interrupt */ - disable_irq_nosync(cqdma->pc[i]->irq); - - /* schedule the tasklet to handle the transactions */ - tasklet_schedule(&cqdma->pc[i]->tasklet); - } } return ret; } -static struct virt_dma_desc *mtk_cqdma_find_active_desc(struct dma_chan *c, - dma_cookie_t cookie) -{ - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); - struct virt_dma_desc *vd; - unsigned long flags; - - spin_lock_irqsave(&cvc->pc->lock, flags); - list_for_each_entry(vd, &cvc->pc->queue, node) - if (vd->tx.cookie == cookie) { - spin_unlock_irqrestore(&cvc->pc->lock, flags); - return vd; - } - spin_unlock_irqrestore(&cvc->pc->lock, flags); - - list_for_each_entry(vd, &cvc->vc.desc_issued, node) - if (vd->tx.cookie == cookie) - return vd; - - return NULL; -} - static enum dma_status mtk_cqdma_tx_status(struct dma_chan *c, dma_cookie_t cookie, struct dma_tx_state *txstate) { - struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); - struct mtk_cqdma_vdesc *cvd; - struct virt_dma_desc *vd; - enum dma_status ret; - unsigned long flags; - size_t bytes = 0; - - ret = dma_cookie_status(c, cookie, txstate); - if (ret == DMA_COMPLETE || !txstate) - return ret; - - spin_lock_irqsave(&cvc->vc.lock, flags); - vd = mtk_cqdma_find_active_desc(c, cookie); - spin_unlock_irqrestore(&cvc->vc.lock, flags); - - if (vd) { - cvd = to_cqdma_vdesc(vd); - bytes = cvd->residue; - } - - dma_set_residue(txstate, bytes); - - return ret; + return dma_cookie_status(c, cookie, txstate); } static void mtk_cqdma_issue_pending(struct dma_chan *c) @@ -473,7 +345,7 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) unsigned long pc_flags; unsigned long vc_flags; - /* acquire PC's lock before VS's lock for lock dependency in tasklet */ + /* acquire PC's lock before VC's lock for lock dependency in ISR */ spin_lock_irqsave(&cvc->pc->lock, pc_flags); spin_lock_irqsave(&cvc->vc.lock, vc_flags); @@ -488,124 +360,56 @@ static void mtk_cqdma_issue_pending(struct dma_chan *c) mtk_cqdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { - struct mtk_cqdma_vdesc **cvd; - struct dma_async_tx_descriptor *tx = NULL, *prev_tx = NULL; - size_t i, tlen, nr_vd; - - /* - * In the case that trsanction length is larger than the - * DMA engine supports, a single memcpy transaction needs - * to be separated into several DMA transactions. - * Each DMA transaction would be described by a CVD, - * and the first one is referred as the parent CVD, - * while the others are child CVDs. - * The parent CVD's tx descriptor is the only tx descriptor - * returned to the DMA user, and it should not be completed - * until all the child CVDs completed. - */ - nr_vd = DIV_ROUND_UP(len, MTK_CQDMA_MAX_LEN); - cvd = kcalloc(nr_vd, sizeof(*cvd), GFP_NOWAIT); + struct mtk_cqdma_vdesc *cvd; + + cvd = kzalloc(sizeof(*cvd), GFP_NOWAIT); if (!cvd) return NULL; - for (i = 0; i < nr_vd; ++i) { - cvd[i] = kzalloc(sizeof(*cvd[i]), GFP_NOWAIT); - if (!cvd[i]) { - for (; i > 0; --i) - kfree(cvd[i - 1]); - return NULL; - } + /* setup dma channel */ + cvd->ch = c; - /* setup dma channel */ - cvd[i]->ch = c; + /* setup sourece, destination, and length */ + cvd->len = len; + cvd->src = src; + cvd->dest = dest; - /* setup sourece, destination, and length */ - tlen = (len > MTK_CQDMA_MAX_LEN) ? MTK_CQDMA_MAX_LEN : len; - cvd[i]->len = tlen; - cvd[i]->src = src; - cvd[i]->dest = dest; - - /* setup tx descriptor */ - tx = vchan_tx_prep(to_virt_chan(c), &cvd[i]->vd, flags); - tx->next = NULL; - - if (!i) { - cvd[0]->residue = len; - } else { - prev_tx->next = tx; - cvd[i]->residue = tlen; - } - - cvd[i]->parent = cvd[0]; - - /* update the src, dest, len, prev_tx for the next CVD */ - src += tlen; - dest += tlen; - len -= tlen; - prev_tx = tx; - } - - return &cvd[0]->vd.tx; + return vchan_tx_prep(to_virt_chan(c), &cvd->vd, flags); } -static void mtk_cqdma_free_inactive_desc(struct dma_chan *c) -{ - struct virt_dma_chan *vc = to_virt_chan(c); - unsigned long flags; - LIST_HEAD(head); - - /* - * set desc_allocated, desc_submitted, - * and desc_issued as the candicates to be freed - */ - spin_lock_irqsave(&vc->lock, flags); - list_splice_tail_init(&vc->desc_allocated, &head); - list_splice_tail_init(&vc->desc_submitted, &head); - list_splice_tail_init(&vc->desc_issued, &head); - spin_unlock_irqrestore(&vc->lock, flags); - - /* free descriptor lists */ - vchan_dma_desc_free_list(vc, &head); -} - -static void mtk_cqdma_free_active_desc(struct dma_chan *c) +static int mtk_cqdma_terminate_all(struct dma_chan *c) { struct mtk_cqdma_vchan *cvc = to_cqdma_vchan(c); - bool sync_needed = false; + struct virt_dma_chan *vc = to_virt_chan(c); unsigned long pc_flags; unsigned long vc_flags; + LIST_HEAD(head); - /* acquire PC's lock first due to lock dependency in dma ISR */ - spin_lock_irqsave(&cvc->pc->lock, pc_flags); - spin_lock_irqsave(&cvc->vc.lock, vc_flags); - - /* synchronization is required if this VC is active */ - if (mtk_cqdma_is_vchan_active(cvc)) { - cvc->issue_synchronize = true; - sync_needed = true; - } + do { + /* acquire PC's lock first due to lock dependency in dma ISR */ + spin_lock_irqsave(&cvc->pc->lock, pc_flags); + spin_lock_irqsave(&cvc->vc.lock, vc_flags); - spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); - spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); + /* wait for the VC to be inactive */ + if (mtk_cqdma_is_vchan_active(cvc)) { + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); + continue; + } - /* waiting for the completion of this VC */ - if (sync_needed) - wait_for_completion(&cvc->issue_completion); + /* get VDs from lists */ + vchan_get_all_descriptors(vc, &head); - /* free all descriptors in list desc_completed */ - vchan_synchronize(&cvc->vc); + /* free all the VDs */ + vchan_dma_desc_free_list(vc, &head); - WARN_ONCE(!list_empty(&cvc->vc.desc_completed), - "Desc pending still in list desc_completed\n"); -} + spin_unlock_irqrestore(&cvc->vc.lock, vc_flags); + spin_unlock_irqrestore(&cvc->pc->lock, pc_flags); -static int mtk_cqdma_terminate_all(struct dma_chan *c) -{ - /* free descriptors not processed yet by hardware */ - mtk_cqdma_free_inactive_desc(c); + break; + } while (1); - /* free descriptors being processed by hardware */ - mtk_cqdma_free_active_desc(c); + vchan_synchronize(&cvc->vc); return 0; } @@ -618,7 +422,7 @@ static int mtk_cqdma_alloc_chan_resources(struct dma_chan *c) u32 i, min_refcnt = U32_MAX, refcnt; unsigned long flags; - /* allocate PC with the minimun refcount */ + /* allocate PC with the minimum refcount */ for (i = 0; i < cqdma->dma_channels; ++i) { refcnt = refcount_read(&cqdma->pc[i]->refcnt); if (refcnt < min_refcnt) { @@ -671,8 +475,9 @@ static void mtk_cqdma_free_chan_resources(struct dma_chan *c) mtk_dma_set(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); /* wait for the completion of flush operation */ - if (mtk_cqdma_poll_engine_done(cvc->pc, false) < 0) - dev_err(cqdma2dev(to_cqdma_dev(c)), "cqdma flush timeout\n"); + if (mtk_cqdma_poll_engine_done(cvc->pc) < 0) + dev_err(cqdma2dev(to_cqdma_dev(c)), + "cqdma flush timeout\n"); /* clear the flush bit and interrupt flag */ mtk_dma_clr(cvc->pc, MTK_CQDMA_FLUSH, MTK_CQDMA_FLUSH_BIT); @@ -787,9 +592,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, "dma-requests", &cqdma->dma_requests)) { - dev_info(&pdev->dev, - "Using %u as missing dma-requests property\n", - MTK_CQDMA_NR_VCHANS); + dev_dbg(&pdev->dev, + "Using %u as missing dma-requests property\n", + MTK_CQDMA_NR_VCHANS); cqdma->dma_requests = MTK_CQDMA_NR_VCHANS; } @@ -797,9 +602,9 @@ static int mtk_cqdma_probe(struct platform_device *pdev) if (pdev->dev.of_node && of_property_read_u32(pdev->dev.of_node, "dma-channels", &cqdma->dma_channels)) { - dev_info(&pdev->dev, - "Using %u as missing dma-channels property\n", - MTK_CQDMA_NR_PCHANS); + dev_dbg(&pdev->dev, + "Using %u as missing dma-channels property\n", + MTK_CQDMA_NR_PCHANS); cqdma->dma_channels = MTK_CQDMA_NR_PCHANS; } @@ -816,7 +621,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) if (!cqdma->pc[i]) return -ENOMEM; - INIT_LIST_HEAD(&cqdma->pc[i]->queue); + cqdma->pc[i]->active_vdesc = NULL; spin_lock_init(&cqdma->pc[i]->lock); refcount_set(&cqdma->pc[i]->refcnt, 0); @@ -860,7 +665,6 @@ static int mtk_cqdma_probe(struct platform_device *pdev) vc = &cqdma->vc[i]; vc->vc.desc_free = mtk_cqdma_vdesc_free; vchan_init(&vc->vc, dd); - init_completion(&vc->issue_completion); } err = dma_async_device_register(dd); @@ -884,12 +688,7 @@ static int mtk_cqdma_probe(struct platform_device *pdev) platform_set_drvdata(pdev, cqdma); - /* initialize tasklet for each PC */ - for (i = 0; i < cqdma->dma_channels; ++i) - tasklet_init(&cqdma->pc[i]->tasklet, mtk_cqdma_tasklet_cb, - (unsigned long)cqdma->pc[i]); - - dev_info(&pdev->dev, "MediaTek CQDMA driver registered\n"); + dev_dbg(&pdev->dev, "MediaTek CQDMA driver registered\n"); return 0; @@ -923,8 +722,6 @@ static int mtk_cqdma_remove(struct platform_device *pdev) /* Waits for any pending IRQ handlers to complete */ synchronize_irq(cqdma->pc[i]->irq); - - tasklet_kill(&cqdma->pc[i]->tasklet); } /* disable hardware */