From patchwork Tue Oct 25 09:03:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tudor Ambarus X-Patchwork-Id: 13018825 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AFA8C38A2D for ; Tue, 25 Oct 2022 09:09:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230274AbiJYJJ4 (ORCPT ); Tue, 25 Oct 2022 05:09:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57548 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231263AbiJYJIm (ORCPT ); Tue, 25 Oct 2022 05:08:42 -0400 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E621C1633B2; Tue, 25 Oct 2022 02:04:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1666688690; x=1698224690; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=XkCIcuyoRQdx86jyITgaYhcRVOpc1kw4bzicnB/+A5g=; b=CfKlyeJbYJJo2FNuycphTwokTYxtaqiqhAJo1vtnQeOzFjdyJGkHzQcB xQng5UUHTnTkzPkVjEGkMY48Imv4Fxa1hST81L7VN2w+bPEiEVOm75oQ6 5xmDg+W5XFko1mag34DpOxWRK/c2xNzkHRylPrH6Y1C+3y0i/OOyYGBAb YQf81Y4VyQoaovIQUASrtGHAuOe0LKbjz7U3ZZkdy6HGyqJ/JN6ptKEed JBFSon41vjWTnBMpltLKj2RlVh/0+XDiTpSlT6RYeEpyNOqlrl6GiyS35 j+x7XWLAdYJM0n+WDnxyCuj5qQQiBxscO2gtWwiUcHaTN+sr2ee8l0SPk Q==; X-IronPort-AV: E=Sophos;i="5.95,211,1661842800"; d="scan'208";a="183777439" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa2.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 25 Oct 2022 02:04:49 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.12; Tue, 25 Oct 2022 02:04:46 -0700 Received: from ROB-ULT-M18064N.mchp-main.com (10.10.115.15) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.2507.12 via Frontend Transport; Tue, 25 Oct 2022 02:04:44 -0700 From: Tudor Ambarus To: , , CC: , , , , , , , "Tudor Ambarus" Subject: [PATCH v2 32/32] dmaengine: at_hdmac: Convert driver to use virt-dma Date: Tue, 25 Oct 2022 12:03:06 +0300 Message-ID: <20221025090306.297886-33-tudor.ambarus@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221025090306.297886-1-tudor.ambarus@microchip.com> References: <20221025090306.297886-1-tudor.ambarus@microchip.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Convert the driver to use the core virt-dma. The driver will be easier to maintain as it uses the list handling and the tasklet from virt-dma. With the conversion replace the election of a new transfer in the tasklet with the election of the new transfer in the interrupt handler. With this we have a shorter idle window as we remove the scheduling latency of the tasklet. I chose to do this while doing the conversion to virt-dma, because if I made a prerequisite patch with the new transfer election in the irq handler, I would have to duplicate some virt-dma code in the at_hdmac driver that would end up being removed at the virt-dma conversion anyway. So do this in a single step. Signed-off-by: Tudor Ambarus Acked-by: Nicolas Ferre --- drivers/dma/Kconfig | 1 + drivers/dma/at_hdmac.c | 1108 +++++++++++++++------------------------- 2 files changed, 403 insertions(+), 706 deletions(-) diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index b73fc89ba877..80848c6b5cd5 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -97,6 +97,7 @@ config AT_HDMAC tristate "Atmel AHB DMA support" depends on ARCH_AT91 select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS help Support the Atmel AHB DMA controller. diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 143d75c18d1e..8858470246e1 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -3,6 +3,7 @@ * Driver for the Atmel AHB DMA Controller (aka HDMA or DMAC on AT91 systems) * * Copyright (C) 2008 Atmel Corporation + * Copyright (C) 2022 Microchip Technology, Inc. and its subsidiaries * * This supports the Atmel AHB DMA Controller found in several Atmel SoCs. * The only Atmel DMA Controller that is not covered by this driver is the one @@ -25,6 +26,7 @@ #include #include "dmaengine.h" +#include "virt-dma.h" /* * Glossary @@ -200,25 +202,31 @@ struct at_lli { u32 dscr; /* chain to next lli */ }; +/** + * struct atdma_sg - atdma scatter gather entry + * @len: length of the current Linked List Item. + * @lli: linked list item that is passed to the DMA controller + * @lli_phys: physical address of the LLI. + */ +struct atdma_sg { + unsigned int len; + struct at_lli *lli; + dma_addr_t lli_phys; +}; + /** * struct at_desc - software descriptor - * @at_lli: hardware lli structure - * @txd: support for the async_tx api - * @desc_node: node on the channed descriptors list - * @len: descriptor byte count + * @vd: pointer to the virtual dma descriptor. + * @atchan: pointer to the atmel dma channel. * @total_len: total transaction byte count + * @sg_len: number of sg entries. + * @sg: array of sgs. */ struct at_desc { - /* FIRST values the hardware uses */ - struct at_lli lli; - - /* THEN values for driver housekeeping */ - struct list_head tx_list; - struct dma_async_tx_descriptor txd; - struct list_head desc_node; - size_t len; + struct virt_dma_desc vd; + struct at_dma_chan *atchan; size_t total_len; - + unsigned int sglen; /* Interleaved data */ size_t boundary; size_t dst_hole; @@ -228,15 +236,9 @@ struct at_desc { bool memset_buffer; dma_addr_t memset_paddr; int *memset_vaddr; + struct atdma_sg sg[]; }; -static inline struct at_desc * -txd_to_at_desc(struct dma_async_tx_descriptor *txd) -{ - return container_of(txd, struct at_desc, txd); -} - - /*-- Channels --------------------------------------------------------*/ /** @@ -245,49 +247,40 @@ txd_to_at_desc(struct dma_async_tx_descriptor *txd) * Manipulated with atomic operations. */ enum atc_status { - ATC_IS_ERROR = 0, ATC_IS_PAUSED = 1, ATC_IS_CYCLIC = 24, }; /** * struct at_dma_chan - internal representation of an Atmel HDMAC channel - * @dma_chan: common dmaengine channel object members + * @vc: virtual dma channel entry. + * @atdma: pointer to the driver data. * @ch_regs: memory mapped register base * @mask: channel index in a mask * @per_if: peripheral interface * @mem_if: memory interface * @status: transmit status information from irq/prep* functions * to tasklet (use atomic operations) - * @tasklet: bottom half to finish transaction work * @save_cfg: configuration register that is saved on suspend/resume cycle * @save_dscr: for cyclic operations, preserve next descriptor address in * the cyclic list on suspend/resume cycle * @dma_sconfig: configuration for slave transfers, passed via * .device_config - * @lock: serializes enqueue/dequeue operations to descriptors lists - * @active_list: list of descriptors dmaengine is being running on - * @queue: list of descriptors ready to be submitted to engine - * @free_list: list of descriptors usable by the channel + * @desc: pointer to the atmel dma descriptor. */ struct at_dma_chan { - struct dma_chan dma_chan; + struct virt_dma_chan vc; + struct at_dma *atdma; void __iomem *ch_regs; u8 mask; u8 per_if; u8 mem_if; unsigned long status; - struct tasklet_struct tasklet; u32 save_cfg; u32 save_dscr; - struct dma_slave_config dma_sconfig; - - spinlock_t lock; - - /* these other elements are all protected by lock */ - struct list_head active_list; - struct list_head queue; - struct list_head free_list; + struct dma_slave_config dma_sconfig; + bool cyclic; + struct at_desc *desc; }; #define channel_readl(atchan, name) \ @@ -296,11 +289,6 @@ struct at_dma_chan { #define channel_writel(atchan, name, val) \ __raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET) -static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan) -{ - return container_of(dchan, struct at_dma_chan, dma_chan); -} - /* * Fix sconfig's burst size according to at_hdmac. We need to convert them as: * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7. @@ -342,7 +330,7 @@ static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width) * @clk: dma controller clock * @save_imr: interrupt mask register that is saved on suspend/resume cycle * @all_chan_mask: all channels availlable in a mask - * @dma_desc_pool: base of DMA descriptor region (DMA address) + * @lli_pool: hw lli table * @chan: channels table to store at_dma_chan structures */ struct at_dma { @@ -353,7 +341,7 @@ struct at_dma { u8 all_chan_mask; - struct dma_pool *dma_desc_pool; + struct dma_pool *lli_pool; struct dma_pool *memset_pool; /* AT THE END channels table */ struct at_dma_chan chan[]; @@ -364,6 +352,16 @@ struct at_dma { #define dma_writel(atdma, name, val) \ __raw_writel((val), (atdma)->regs + AT_DMA_##name) +static inline struct at_desc *to_atdma_desc(struct dma_async_tx_descriptor *t) +{ + return container_of(t, struct at_desc, vd.tx); +} + +static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *chan) +{ + return container_of(chan, struct at_dma_chan, vc.chan); +} + static inline struct at_dma *to_at_dma(struct dma_device *ddev) { return container_of(ddev, struct at_dma, dma_device); @@ -380,15 +378,15 @@ static struct device *chan2dev(struct dma_chan *chan) #if defined(VERBOSE_DEBUG) static void vdbg_dump_regs(struct at_dma_chan *atchan) { - struct at_dma *atdma = to_at_dma(atchan->dma_chan.device); + struct at_dma *atdma = to_at_dma(atchan->vc.chan.device); - dev_err(chan2dev(&atchan->dma_chan), + dev_err(chan2dev(&atchan->vc.chan), " channel %d : imr = 0x%x, chsr = 0x%x\n", - atchan->dma_chan.chan_id, + atchan->vc.chan.chan_id, dma_readl(atdma, EBCIMR), dma_readl(atdma, CHSR)); - dev_err(chan2dev(&atchan->dma_chan), + dev_err(chan2dev(&atchan->vc.chan), " channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n", channel_readl(atchan, SADDR), channel_readl(atchan, DADDR), @@ -403,7 +401,7 @@ static void vdbg_dump_regs(struct at_dma_chan *atchan) {} static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli) { - dev_crit(chan2dev(&atchan->dma_chan), + dev_crit(chan2dev(&atchan->vc.chan), "desc: s%pad d%pad ctrl0x%x:0x%x l%pad\n", &lli->saddr, &lli->daddr, lli->ctrla, lli->ctrlb, &lli->dscr); @@ -440,7 +438,7 @@ static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id) */ static inline int atc_chan_is_enabled(struct at_dma_chan *atchan) { - struct at_dma *atdma = to_at_dma(atchan->dma_chan.device); + struct at_dma *atdma = to_at_dma(atchan->vc.chan.device); return !!(dma_readl(atdma, CHSR) & atchan->mask); } @@ -464,18 +462,19 @@ static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan) } /** - * set_desc_eol - set end-of-link to descriptor so it will end transfer + * set_lli_eol - set end-of-link to descriptor so it will end transfer * @desc: descriptor, signle or at the end of a chain, to end chain on + * @i: index of the atmel scatter gather entry that is at the end of the chain. */ -static void set_desc_eol(struct at_desc *desc) +static void set_lli_eol(struct at_desc *desc, unsigned int i) { - u32 ctrlb = desc->lli.ctrlb; + u32 ctrlb = desc->sg[i].lli->ctrlb; ctrlb &= ~ATC_IEN; ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS; - desc->lli.ctrlb = ctrlb; - desc->lli.dscr = 0; + desc->sg[i].lli->ctrlb = ctrlb; + desc->sg[i].lli->dscr = 0; } #define ATC_DEFAULT_CFG FIELD_PREP(ATC_FIFOCFG, ATC_FIFOCFG_HALFFIFO) @@ -518,13 +517,6 @@ struct at_dma_slave { u32 cfg; }; -/* prototypes */ -static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx); -static void atc_issue_pending(struct dma_chan *chan); - - -/*----------------------------------------------------------------------*/ - static inline unsigned int atc_get_xfer_width(dma_addr_t src, dma_addr_t dst, size_t len) { @@ -540,196 +532,72 @@ static inline unsigned int atc_get_xfer_width(dma_addr_t src, dma_addr_t dst, return width; } -static struct at_desc *atc_first_active(struct at_dma_chan *atchan) +static void atdma_lli_chain(struct at_desc *desc, unsigned int i) { - return list_first_entry(&atchan->active_list, - struct at_desc, desc_node); -} + struct atdma_sg *atdma_sg = &desc->sg[i]; -static struct at_desc *atc_first_queued(struct at_dma_chan *atchan) -{ - return list_first_entry(&atchan->queue, - struct at_desc, desc_node); -} - -/** - * atc_alloc_descriptor - allocate and return an initialized descriptor - * @chan: the channel to allocate descriptors for - * @gfp_flags: GFP allocation flags - * - * Note: The ack-bit is positioned in the descriptor flag at creation time - * to make initial allocation more convenient. This bit will be cleared - * and control will be given to client at usage time (during - * preparation functions). - */ -static struct at_desc *atc_alloc_descriptor(struct dma_chan *chan, - gfp_t gfp_flags) -{ - struct at_desc *desc = NULL; - struct at_dma *atdma = to_at_dma(chan->device); - dma_addr_t phys; - - desc = dma_pool_zalloc(atdma->dma_desc_pool, gfp_flags, &phys); - if (desc) { - INIT_LIST_HEAD(&desc->tx_list); - dma_async_tx_descriptor_init(&desc->txd, chan); - /* txd.flags will be overwritten in prep functions */ - desc->txd.flags = DMA_CTRL_ACK; - desc->txd.tx_submit = atc_tx_submit; - desc->txd.phys = phys; - } - - return desc; -} - -/** - * atc_desc_get - get an unused descriptor from free_list - * @atchan: channel we want a new descriptor for - */ -static struct at_desc *atc_desc_get(struct at_dma_chan *atchan) -{ - struct at_desc *desc, *_desc; - struct at_desc *ret = NULL; - unsigned long flags; - unsigned int i = 0; - - spin_lock_irqsave(&atchan->lock, flags); - list_for_each_entry_safe(desc, _desc, &atchan->free_list, desc_node) { - i++; - if (async_tx_test_ack(&desc->txd)) { - list_del(&desc->desc_node); - ret = desc; - break; - } - dev_dbg(chan2dev(&atchan->dma_chan), - "desc %p not ACKed\n", desc); - } - spin_unlock_irqrestore(&atchan->lock, flags); - dev_vdbg(chan2dev(&atchan->dma_chan), - "scanned %u descriptors on freelist\n", i); - - /* no more descriptor available in initial pool: create one more */ - if (!ret) - ret = atc_alloc_descriptor(&atchan->dma_chan, GFP_NOWAIT); - - return ret; -} - -/** - * atc_desc_put - move a descriptor, including any children, to the free list - * @atchan: channel we work on - * @desc: descriptor, at the head of a chain, to move to free list - */ -static void atc_desc_put(struct at_dma_chan *atchan, struct at_desc *desc) -{ - if (desc) { - struct at_desc *child; - unsigned long flags; - - spin_lock_irqsave(&atchan->lock, flags); - list_for_each_entry(child, &desc->tx_list, desc_node) - dev_vdbg(chan2dev(&atchan->dma_chan), - "moving child desc %p to freelist\n", - child); - list_splice_init(&desc->tx_list, &atchan->free_list); - dev_vdbg(chan2dev(&atchan->dma_chan), - "moving desc %p to freelist\n", desc); - list_add(&desc->desc_node, &atchan->free_list); - spin_unlock_irqrestore(&atchan->lock, flags); - } -} - -/** - * atc_desc_chain - build chain adding a descriptor - * @first: address of first descriptor of the chain - * @prev: address of previous descriptor 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; + if (i) + desc->sg[i - 1].lli->dscr = atdma_sg->lli_phys; } /** * atc_dostart - starts the DMA engine for real * @atchan: the channel we want to start - * @first: first descriptor in the list we want to begin with - * - * Called with atchan->lock held and bh disabled */ -static void atc_dostart(struct at_dma_chan *atchan, struct at_desc *first) +static void atc_dostart(struct at_dma_chan *atchan) { - struct at_dma *atdma = to_at_dma(atchan->dma_chan.device); + struct virt_dma_desc *vd = vchan_next_desc(&atchan->vc); + struct at_desc *desc; - /* ASSERT: channel is idle */ - if (atc_chan_is_enabled(atchan)) { - dev_err(chan2dev(&atchan->dma_chan), - "BUG: Attempted to start non-idle channel\n"); - dev_err(chan2dev(&atchan->dma_chan), - " channel: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n", - channel_readl(atchan, SADDR), - channel_readl(atchan, DADDR), - channel_readl(atchan, CTRLA), - channel_readl(atchan, CTRLB), - channel_readl(atchan, DSCR)); - - /* The tasklet will hopefully advance the queue... */ + if (!vd) { + atchan->desc = NULL; return; } vdbg_dump_regs(atchan); + list_del(&vd->node); + atchan->desc = desc = to_atdma_desc(&vd->tx); + channel_writel(atchan, SADDR, 0); channel_writel(atchan, DADDR, 0); channel_writel(atchan, CTRLA, 0); channel_writel(atchan, CTRLB, 0); - channel_writel(atchan, DSCR, first->txd.phys); - channel_writel(atchan, SPIP, FIELD_PREP(ATC_SPIP_HOLE, - first->src_hole) | - FIELD_PREP(ATC_SPIP_BOUNDARY, first->boundary)); - channel_writel(atchan, DPIP, FIELD_PREP(ATC_DPIP_HOLE, - first->dst_hole) | - FIELD_PREP(ATC_DPIP_BOUNDARY, first->boundary)); + channel_writel(atchan, DSCR, desc->sg[0].lli_phys); + channel_writel(atchan, SPIP, + FIELD_PREP(ATC_SPIP_HOLE, desc->src_hole) | + FIELD_PREP(ATC_SPIP_BOUNDARY, desc->boundary)); + channel_writel(atchan, DPIP, + FIELD_PREP(ATC_DPIP_HOLE, desc->dst_hole) | + FIELD_PREP(ATC_DPIP_BOUNDARY, desc->boundary)); + /* Don't allow CPU to reorder channel enable. */ wmb(); - dma_writel(atdma, CHER, atchan->mask); + dma_writel(atchan->atdma, CHER, atchan->mask); vdbg_dump_regs(atchan); } -/* - * atc_get_desc_by_cookie - get the descriptor of a cookie - * @atchan: the DMA channel - * @cookie: the cookie to get the descriptor for - */ -static struct at_desc *atc_get_desc_by_cookie(struct at_dma_chan *atchan, - dma_cookie_t cookie) +static void atdma_desc_free(struct virt_dma_desc *vd) { - struct at_desc *desc, *_desc; + struct at_dma *atdma = to_at_dma(vd->tx.chan->device); + struct at_desc *desc = to_atdma_desc(&vd->tx); + unsigned int i; - list_for_each_entry_safe(desc, _desc, &atchan->queue, desc_node) { - if (desc->txd.cookie == cookie) - return desc; + for (i = 0; i < desc->sglen; i++) { + if (desc->sg[i].lli) + dma_pool_free(atdma->lli_pool, desc->sg[i].lli, + desc->sg[i].lli_phys); } - list_for_each_entry_safe(desc, _desc, &atchan->active_list, desc_node) { - if (desc->txd.cookie == cookie) - return desc; + /* If the transfer was a memset, free our temporary buffer */ + if (desc->memset_buffer) { + dma_pool_free(atdma->memset_pool, desc->memset_vaddr, + desc->memset_paddr); + desc->memset_buffer = false; } - return NULL; + kfree(desc); } /** @@ -756,20 +624,19 @@ static inline u32 atc_calc_bytes_left(u32 current_len, u32 ctrla) /** * atc_get_llis_residue - Get residue for a hardware linked list transfer * - * Calculate the residue by removing the length of the child descriptors already - * transferred from the total length. To get the current child descriptor we can - * use the value of the channel's DSCR register and compare it against the value - * of the hardware linked list structure of each child descriptor. + * Calculate the residue by removing the length of the Linked List Item (LLI) + * already transferred from the total length. To get the current LLI we can use + * the value of the channel's DSCR register and compare it against the DSCR + * value of each LLI. * * The CTRLA register provides us with the amount of data already read from the - * source for the current child descriptor. So we can compute a more accurate - * residue by also removing the number of bytes corresponding to this amount of - * data. + * source for the LLI. So we can compute a more accurate residue by also + * removing the number of bytes corresponding to this amount of data. * * However, the DSCR and CTRLA registers cannot be read both atomically. Hence a - * race condition may occur: the first read register may refer to one child - * descriptor whereas the second read may refer to a later child descriptor in - * the list because of the DMA transfer progression inbetween the two reads. + * race condition may occur: the first read register may refer to one LLI + * whereas the second read may refer to a later LLI in the list because of the + * DMA transfer progression inbetween the two reads. * * One solution could have been to pause the DMA transfer, read the DSCR and * CTRLA then resume the DMA transfer. Nonetheless, this approach presents some @@ -786,12 +653,11 @@ static inline u32 atc_calc_bytes_left(u32 current_len, u32 ctrla) * Then we'd rather use another solution: the DSCR is read a first time, the * CTRLA is read in turn, next the DSCR is read a second time. If the two * consecutive read values of the DSCR are the same then we assume both refers - * to the very same child descriptor as well as the CTRLA value read inbetween - * does. For cyclic tranfers, the assumption is that a full loop is "not so - * fast". If the two DSCR values are different, we read again the CTRLA then the - * DSCR till two consecutive read values from DSCR are equal or till the - * maximum trials is reach. This algorithm is very unlikely not to find a stable - * value for DSCR. + * to the very same LLI as well as the CTRLA value read inbetween does. For + * cyclic tranfers, the assumption is that a full loop is "not so fast". If the + * two DSCR values are different, we read again the CTRLA then the DSCR till two + * consecutive read values from DSCR are equal or till the maximum trials is + * reach. This algorithm is very unlikely not to find a stable value for DSCR. * @atchan: pointer to an atmel hdmac channel. * @desc: pointer to the descriptor for which the residue is calculated. * @residue: residue to be set to dma_tx_state. @@ -800,7 +666,6 @@ static inline u32 atc_calc_bytes_left(u32 current_len, u32 ctrla) static int atc_get_llis_residue(struct at_dma_chan *atchan, struct at_desc *desc, u32 *residue) { - struct at_desc *child; u32 len, ctrla, dscr; unsigned int i; @@ -836,24 +701,25 @@ static int atc_get_llis_residue(struct at_dma_chan *atchan, return -ETIMEDOUT; /* For the first descriptor we can be more accurate. */ - if (desc->lli.dscr == dscr) { + if (desc->sg[0].lli->dscr == dscr) { *residue = atc_calc_bytes_left(len, ctrla); return 0; } + len -= desc->sg[0].len; - len -= desc->len; - list_for_each_entry(child, &desc->tx_list, desc_node) { - if (child->lli.dscr == dscr) + for (i = 1; i < desc->sglen; i++) { + if (desc->sg[i].lli && desc->sg[i].lli->dscr == dscr) break; - len -= child->len; + len -= desc->sg[i].len; } /* - * For the current descriptor in the chain we can calculate the - * remaining bytes using the channel's register. + * For the current LLI in the chain we can calculate the remaining bytes + * using the channel's CTRLA register. */ *residue = atc_calc_bytes_left(len, ctrla); return 0; + } /** @@ -867,139 +733,42 @@ static int atc_get_llis_residue(struct at_dma_chan *atchan, static int atc_get_residue(struct dma_chan *chan, dma_cookie_t cookie, u32 *residue) { - struct at_dma_chan *atchan = to_at_dma_chan(chan); - struct at_desc *desc_first = atc_first_active(atchan); - struct at_desc *desc; + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct virt_dma_desc *vd; + struct at_desc *desc = NULL; u32 len, ctrla; - /* - * If the cookie doesn't match to the currently running transfer then - * we can return the total length of the associated DMA transfer, - * because it is still queued. - */ - desc = atc_get_desc_by_cookie(atchan, cookie); - if (desc == NULL) + vd = vchan_find_desc(&atchan->vc, cookie); + if (vd) + desc = to_atdma_desc(&vd->tx); + else if (atchan->desc && atchan->desc->vd.tx.cookie == cookie) + desc = atchan->desc; + + if (!desc) return -EINVAL; - else if (desc != desc_first) - return desc->total_len; - if (desc_first->lli.dscr) + if (desc->sg[0].lli->dscr) /* hardware linked list transfer */ - return atc_get_llis_residue(atchan, desc_first, residue); + return atc_get_llis_residue(atchan, desc, residue); /* single transfer */ - len = desc_first->total_len; + len = desc->total_len; ctrla = channel_readl(atchan, CTRLA); *residue = atc_calc_bytes_left(len, ctrla); return 0; } -/** - * atc_chain_complete - finish work for one transaction chain - * @atchan: channel we work on - * @desc: descriptor at the head of the chain we want do complete - */ -static void -atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) -{ - struct dma_async_tx_descriptor *txd = &desc->txd; - struct at_dma *atdma = to_at_dma(atchan->dma_chan.device); - unsigned long flags; - - dev_vdbg(chan2dev(&atchan->dma_chan), - "descriptor %u complete\n", txd->cookie); - - spin_lock_irqsave(&atchan->lock, flags); - - /* mark the descriptor as complete for non cyclic cases only */ - if (!atc_chan_is_cyclic(atchan)) - dma_cookie_complete(txd); - - spin_unlock_irqrestore(&atchan->lock, flags); - - dma_descriptor_unmap(txd); - /* for cyclic transfers, - * no need to replay callback function while stopping */ - if (!atc_chan_is_cyclic(atchan)) - dmaengine_desc_get_callback_invoke(txd, NULL); - - dma_run_dependencies(txd); - - spin_lock_irqsave(&atchan->lock, flags); - /* move children to free_list */ - list_splice_init(&desc->tx_list, &atchan->free_list); - /* add myself to free_list */ - list_add(&desc->desc_node, &atchan->free_list); - spin_unlock_irqrestore(&atchan->lock, flags); - - /* If the transfer was a memset, free our temporary buffer */ - if (desc->memset_buffer) { - dma_pool_free(atdma->memset_pool, desc->memset_vaddr, - desc->memset_paddr); - desc->memset_buffer = false; - } -} - -/** - * atc_advance_work - at the end of a transaction, move forward - * @atchan: channel where the transaction ended - */ -static void atc_advance_work(struct at_dma_chan *atchan) -{ - struct at_desc *desc; - unsigned long flags; - - dev_vdbg(chan2dev(&atchan->dma_chan), "advance_work\n"); - - spin_lock_irqsave(&atchan->lock, flags); - if (atc_chan_is_enabled(atchan) || list_empty(&atchan->active_list)) - return spin_unlock_irqrestore(&atchan->lock, flags); - - desc = atc_first_active(atchan); - /* Remove the transfer node from the active list. */ - list_del_init(&desc->desc_node); - spin_unlock_irqrestore(&atchan->lock, flags); - atc_chain_complete(atchan, desc); - - /* advance work */ - spin_lock_irqsave(&atchan->lock, flags); - if (!list_empty(&atchan->active_list)) { - desc = atc_first_queued(atchan); - list_move_tail(&desc->desc_node, &atchan->active_list); - atc_dostart(atchan, desc); - } - spin_unlock_irqrestore(&atchan->lock, flags); -} - - /** * atc_handle_error - handle errors reported by DMA controller - * @atchan: channel where error occurs + * @atchan: channel where error occurs. + * @i: channel index */ -static void atc_handle_error(struct at_dma_chan *atchan) +static void atc_handle_error(struct at_dma_chan *atchan, unsigned int i) { - struct at_desc *bad_desc; - struct at_desc *desc; - struct at_desc *child; - unsigned long flags; - - spin_lock_irqsave(&atchan->lock, flags); - /* - * The descriptor currently at the head of the active list is - * broked. Since we don't have any way to report errors, we'll - * just have to scream loudly and try to carry on. - */ - bad_desc = atc_first_active(atchan); - list_del_init(&bad_desc->desc_node); - - /* Try to restart the controller */ - if (!list_empty(&atchan->active_list)) { - desc = atc_first_queued(atchan); - list_move_tail(&desc->desc_node, &atchan->active_list); - atc_dostart(atchan, desc); - } + struct at_desc *desc = atchan->desc; - spin_unlock_irqrestore(&atchan->lock, flags); + /* Disable channel on AHB error */ + dma_writel(atchan->atdma, CHDR, AT_DMA_RES(i) | atchan->mask); /* * KERN_CRITICAL may seem harsh, but since this only happens @@ -1008,47 +777,37 @@ static void atc_handle_error(struct at_dma_chan *atchan) * controller flagged an error instead of scribbling over * random memory locations. */ - dev_crit(chan2dev(&atchan->dma_chan), - "Bad descriptor submitted for DMA!\n"); - dev_crit(chan2dev(&atchan->dma_chan), - " cookie: %d\n", bad_desc->txd.cookie); - atc_dump_lli(atchan, &bad_desc->lli); - list_for_each_entry(child, &bad_desc->tx_list, desc_node) - atc_dump_lli(atchan, &child->lli); - - /* Pretend the descriptor completed successfully */ - atc_chain_complete(atchan, bad_desc); -} - -/** - * atc_handle_cyclic - at the end of a period, run callback function - * @atchan: channel used for cyclic operations - */ -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; - - dev_vdbg(chan2dev(&atchan->dma_chan), - "new cyclic period llp 0x%08x\n", - channel_readl(atchan, DSCR)); - - dmaengine_desc_get_callback_invoke(txd, NULL); + dev_crit(chan2dev(&atchan->vc.chan), "Bad descriptor submitted for DMA!\n"); + dev_crit(chan2dev(&atchan->vc.chan), "cookie: %d\n", + desc->vd.tx.cookie); + for (i = 0; i < desc->sglen; i++) + atc_dump_lli(atchan, desc->sg[i].lli); } -/*-- IRQ & Tasklet ---------------------------------------------------*/ - -static void atc_tasklet(struct tasklet_struct *t) +static void atdma_handle_chan_done(struct at_dma_chan *atchan, u32 pending, + unsigned int i) { - struct at_dma_chan *atchan = from_tasklet(atchan, t, tasklet); + struct at_desc *desc; - if (test_and_clear_bit(ATC_IS_ERROR, &atchan->status)) - return atc_handle_error(atchan); + spin_lock(&atchan->vc.lock); + desc = atchan->desc; - if (atc_chan_is_cyclic(atchan)) - return atc_handle_cyclic(atchan); + if (desc) { + if (pending & AT_DMA_ERR(i)) { + atc_handle_error(atchan, i); + /* Pretend the descriptor completed successfully */ + } - atc_advance_work(atchan); + if (atc_chan_is_cyclic(atchan)) { + vchan_cyclic_callback(&desc->vd); + } else { + vchan_cookie_complete(&desc->vd); + atchan->desc = NULL; + if (!(atc_chan_is_enabled(atchan))) + atc_dostart(atchan); + } + } + spin_unlock(&atchan->vc.lock); } static irqreturn_t at_dma_interrupt(int irq, void *dev_id) @@ -1073,17 +832,10 @@ static irqreturn_t at_dma_interrupt(int irq, void *dev_id) for (i = 0; i < atdma->dma_device.chancnt; i++) { atchan = &atdma->chan[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, - AT_DMA_RES(i) | atchan->mask); - /* Give information to tasklet */ - set_bit(ATC_IS_ERROR, &atchan->status); - } - tasklet_schedule(&atchan->tasklet); - ret = IRQ_HANDLED; - } + if (!(pending & (AT_DMA_BTC(i) | AT_DMA_ERR(i)))) + continue; + atdma_handle_chan_done(atchan, pending, i); + ret = IRQ_HANDLED; } } while (pending); @@ -1091,35 +843,7 @@ static irqreturn_t at_dma_interrupt(int irq, void *dev_id) return ret; } - /*-- DMA Engine API --------------------------------------------------*/ - -/** - * atc_tx_submit - set the prepared descriptor(s) to be executed by the engine - * @tx: descriptor at the head of the transaction chain - * - * Queue chain if DMA engine is working already - * - * Cookie increment and adding to active_list or queue must be atomic - */ -static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx) -{ - struct at_desc *desc = txd_to_at_desc(tx); - struct at_dma_chan *atchan = to_at_dma_chan(tx->chan); - dma_cookie_t cookie; - unsigned long flags; - - spin_lock_irqsave(&atchan->lock, flags); - cookie = dma_cookie_assign(tx); - - list_add_tail(&desc->desc_node, &atchan->queue); - spin_unlock_irqrestore(&atchan->lock, flags); - - dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u\n", - desc->txd.cookie); - return cookie; -} - /** * atc_prep_dma_interleaved - prepare memory to memory interleaved operation * @chan: the channel to prepare operation on @@ -1131,9 +855,12 @@ atc_prep_dma_interleaved(struct dma_chan *chan, struct dma_interleaved_template *xt, unsigned long flags) { + struct at_dma *atdma = to_at_dma(chan->device); struct at_dma_chan *atchan = to_at_dma_chan(chan); struct data_chunk *first; - struct at_desc *desc = NULL; + struct atdma_sg *atdma_sg; + struct at_desc *desc; + struct at_lli *lli; size_t xfer_count; unsigned int dwidth; u32 ctrla; @@ -1172,8 +899,7 @@ atc_prep_dma_interleaved(struct dma_chan *chan, len += chunk->size; } - dwidth = atc_get_xfer_width(xt->src_start, - xt->dst_start, len); + dwidth = atc_get_xfer_width(xt->src_start, xt->dst_start, len); xfer_count = len >> dwidth; if (xfer_count > ATC_BTSIZE_MAX) { @@ -1190,32 +916,34 @@ atc_prep_dma_interleaved(struct dma_chan *chan, ATC_SRC_PIP | ATC_DST_PIP | FIELD_PREP(ATC_FC, ATC_FC_MEM2MEM); - /* create the transfer */ - desc = atc_desc_get(atchan); - if (!desc) { - dev_err(chan2dev(chan), - "%s: couldn't allocate our descriptor\n", __func__); + desc = kzalloc(struct_size(desc, sg, 1), GFP_ATOMIC); + if (!desc) + return NULL; + desc->sglen = 1; + + atdma_sg = desc->sg; + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, GFP_NOWAIT, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) { + kfree(desc); return NULL; } + lli = atdma_sg->lli; - desc->lli.saddr = xt->src_start; - desc->lli.daddr = xt->dst_start; - desc->lli.ctrla = ctrla | xfer_count; - desc->lli.ctrlb = ctrlb; + lli->saddr = xt->src_start; + lli->daddr = xt->dst_start; + lli->ctrla = ctrla | xfer_count; + lli->ctrlb = ctrlb; desc->boundary = first->size >> dwidth; desc->dst_hole = (dmaengine_get_dst_icg(xt, first) >> dwidth) + 1; desc->src_hole = (dmaengine_get_src_icg(xt, first) >> dwidth) + 1; - desc->txd.cookie = -EBUSY; - desc->total_len = desc->len = len; - - /* set end-of-link to the last link descriptor of list*/ - set_desc_eol(desc); - - desc->txd.flags = flags; /* client is in control of this ack */ + atdma_sg->len = len; + desc->total_len = len; - return &desc->txd; + set_lli_eol(desc, 0); + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); } /** @@ -1230,25 +958,32 @@ static struct dma_async_tx_descriptor * atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { + struct at_dma *atdma = to_at_dma(chan->device); struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_desc *desc = NULL; - struct at_desc *first = NULL; - struct at_desc *prev = NULL; size_t xfer_count; size_t offset; + size_t sg_len; unsigned int src_width; unsigned int dst_width; + unsigned int i; u32 ctrla; u32 ctrlb; - dev_vdbg(chan2dev(chan), "prep_dma_memcpy: d%pad s%pad l0x%zx f0x%lx\n", - &dest, &src, len, flags); + dev_dbg(chan2dev(chan), "prep_dma_memcpy: d%pad s%pad l0x%zx f0x%lx\n", + &dest, &src, len, flags); if (unlikely(!len)) { - dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n"); + dev_err(chan2dev(chan), "prep_dma_memcpy: length is zero!\n"); return NULL; } + sg_len = DIV_ROUND_UP(len, ATC_BTSIZE_MAX); + desc = kzalloc(struct_size(desc, sg, sg_len), GFP_ATOMIC); + if (!desc) + return NULL; + desc->sglen = sg_len; + ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | FIELD_PREP(ATC_SRC_ADDR_MODE, ATC_SRC_ADDR_MODE_INCR) | FIELD_PREP(ATC_DST_ADDR_MODE, ATC_DST_ADDR_MODE_INCR) | @@ -1263,50 +998,49 @@ atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, ctrla = FIELD_PREP(ATC_SRC_WIDTH, src_width) | FIELD_PREP(ATC_DST_WIDTH, dst_width); - for (offset = 0; offset < len; offset += xfer_count << src_width) { - xfer_count = min_t(size_t, (len - offset) >> src_width, - ATC_BTSIZE_MAX); + for (offset = 0, i = 0; offset < len; + offset += xfer_count << src_width, i++) { + struct atdma_sg *atdma_sg = &desc->sg[i]; + struct at_lli *lli; - desc = atc_desc_get(atchan); - if (!desc) + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, GFP_NOWAIT, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) goto err_desc_get; + lli = atdma_sg->lli; + + xfer_count = min_t(size_t, (len - offset) >> src_width, + ATC_BTSIZE_MAX); - desc->lli.saddr = src + offset; - desc->lli.daddr = dest + offset; - desc->lli.ctrla = ctrla | xfer_count; - desc->lli.ctrlb = ctrlb; + lli->saddr = src + offset; + lli->daddr = dest + offset; + lli->ctrla = ctrla | xfer_count; + lli->ctrlb = ctrlb; - desc->txd.cookie = 0; - desc->len = xfer_count << src_width; + desc->sg[i].len = xfer_count << src_width; - atc_desc_chain(&first, &prev, desc); + atdma_lli_chain(desc, i); } - /* First descriptor of the chain embedds additional information */ - first->txd.cookie = -EBUSY; - first->total_len = len; + desc->total_len = len; /* set end-of-link to the last link descriptor of list*/ - set_desc_eol(desc); - - first->txd.flags = flags; /* client is in control of this ack */ + set_lli_eol(desc, i - 1); - return &first->txd; + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); err_desc_get: - atc_desc_put(atchan, first); + atdma_desc_free(&desc->vd); return NULL; } -static struct at_desc *atc_create_memset_desc(struct dma_chan *chan, - dma_addr_t psrc, - dma_addr_t pdst, - size_t len) +static int atdma_create_memset_lli(struct dma_chan *chan, + struct atdma_sg *atdma_sg, + dma_addr_t psrc, dma_addr_t pdst, size_t len) { - struct at_dma_chan *atchan = to_at_dma_chan(chan); - struct at_desc *desc; + struct at_dma *atdma = to_at_dma(chan->device); + struct at_lli *lli; size_t xfer_count; - u32 ctrla = FIELD_PREP(ATC_SRC_WIDTH, 2) | FIELD_PREP(ATC_DST_WIDTH, 2); u32 ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | FIELD_PREP(ATC_SRC_ADDR_MODE, ATC_SRC_ADDR_MODE_FIXED) | @@ -1315,27 +1049,24 @@ static struct at_desc *atc_create_memset_desc(struct dma_chan *chan, xfer_count = len >> 2; if (xfer_count > ATC_BTSIZE_MAX) { - dev_err(chan2dev(chan), "%s: buffer is too big\n", - __func__); - return NULL; + dev_err(chan2dev(chan), "%s: buffer is too big\n", __func__); + return -EINVAL; } - desc = atc_desc_get(atchan); - if (!desc) { - dev_err(chan2dev(chan), "%s: can't get a descriptor\n", - __func__); - return NULL; - } + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, GFP_NOWAIT, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) + return -ENOMEM; + lli = atdma_sg->lli; - desc->lli.saddr = psrc; - desc->lli.daddr = pdst; - desc->lli.ctrla = ctrla | xfer_count; - desc->lli.ctrlb = ctrlb; + lli->saddr = psrc; + lli->daddr = pdst; + lli->ctrla = ctrla | xfer_count; + lli->ctrlb = ctrlb; - desc->txd.cookie = 0; - desc->len = len; + atdma_sg->len = len; - return desc; + return 0; } /** @@ -1350,11 +1081,13 @@ static struct dma_async_tx_descriptor * atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags) { + struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); struct at_desc *desc; void __iomem *vaddr; dma_addr_t paddr; char fill_pattern; + int ret; dev_vdbg(chan2dev(chan), "%s: d%pad v0x%x l0x%zx f0x%lx\n", __func__, &dest, value, len, flags); @@ -1385,27 +1118,28 @@ atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, (fill_pattern << 8) | fill_pattern; - desc = atc_create_memset_desc(chan, paddr, dest, len); - if (!desc) { - dev_err(chan2dev(chan), "%s: couldn't get a descriptor\n", - __func__); + desc = kzalloc(struct_size(desc, sg, 1), GFP_ATOMIC); + if (!desc) goto err_free_buffer; - } + desc->sglen = 1; + + ret = atdma_create_memset_lli(chan, desc->sg, paddr, dest, len); + if (ret) + goto err_free_desc; desc->memset_paddr = paddr; desc->memset_vaddr = vaddr; desc->memset_buffer = true; - desc->txd.cookie = -EBUSY; desc->total_len = len; /* set end-of-link on the descriptor */ - set_desc_eol(desc); - - desc->txd.flags = flags; + set_lli_eol(desc, 0); - return &desc->txd; + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); +err_free_desc: + kfree(desc); err_free_buffer: dma_pool_free(atdma->memset_pool, vaddr, paddr); return NULL; @@ -1419,12 +1153,13 @@ atc_prep_dma_memset_sg(struct dma_chan *chan, { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - struct at_desc *desc = NULL, *first = NULL, *prev = NULL; + struct at_desc *desc; struct scatterlist *sg; void __iomem *vaddr; dma_addr_t paddr; size_t total_len = 0; int i; + int ret; dev_vdbg(chan2dev(chan), "%s: v0x%x l0x%zx f0x%lx\n", __func__, value, sg_len, flags); @@ -1443,6 +1178,11 @@ atc_prep_dma_memset_sg(struct dma_chan *chan, } *(u32*)vaddr = value; + desc = kzalloc(struct_size(desc, sg, sg_len), GFP_ATOMIC); + if (!desc) + goto err_free_dma_buf; + desc->sglen = sg_len; + for_each_sg(sgl, sg, sg_len, i) { dma_addr_t dest = sg_dma_address(sg); size_t len = sg_dma_len(sg); @@ -1453,38 +1193,33 @@ atc_prep_dma_memset_sg(struct dma_chan *chan, if (!is_dma_fill_aligned(chan->device, dest, 0, len)) { dev_err(chan2dev(chan), "%s: buffer is not aligned\n", __func__); - goto err_put_desc; + goto err_free_desc; } - desc = atc_create_memset_desc(chan, paddr, dest, len); - if (!desc) - goto err_put_desc; - - atc_desc_chain(&first, &prev, desc); + ret = atdma_create_memset_lli(chan, &desc->sg[i], paddr, dest, + len); + if (ret) + goto err_free_desc; + atdma_lli_chain(desc, i); total_len += len; } - /* - * Only set the buffer pointers on the last descriptor to - * avoid free'ing while we have our transfer still going - */ desc->memset_paddr = paddr; desc->memset_vaddr = vaddr; desc->memset_buffer = true; - first->txd.cookie = -EBUSY; - first->total_len = total_len; + desc->total_len = total_len; /* set end-of-link on the descriptor */ - set_desc_eol(desc); - - first->txd.flags = flags; + set_lli_eol(desc, i - 1); - return &first->txd; + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); -err_put_desc: - atc_desc_put(atchan, first); +err_free_desc: + atdma_desc_free(&desc->vd); +err_free_dma_buf: + dma_pool_free(atdma->memset_pool, vaddr, paddr); return NULL; } @@ -1502,11 +1237,11 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { + struct at_dma *atdma = to_at_dma(chan->device); struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; struct dma_slave_config *sconfig = &atchan->dma_sconfig; - struct at_desc *first = NULL; - struct at_desc *prev = NULL; + struct at_desc *desc; u32 ctrla; u32 ctrlb; dma_addr_t reg; @@ -1526,6 +1261,11 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, return NULL; } + desc = kzalloc(struct_size(desc, sg, sg_len), GFP_ATOMIC); + if (!desc) + return NULL; + desc->sglen = sg_len; + ctrla = FIELD_PREP(ATC_SCSIZE, sconfig->src_maxburst) | FIELD_PREP(ATC_DCSIZE, sconfig->dst_maxburst); ctrlb = ATC_IEN; @@ -1542,13 +1282,17 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, FIELD_PREP(ATC_DIF, atchan->per_if); reg = sconfig->dst_addr; for_each_sg(sgl, sg, sg_len, i) { - struct at_desc *desc; + struct atdma_sg *atdma_sg = &desc->sg[i]; + struct at_lli *lli; u32 len; u32 mem; - desc = atc_desc_get(atchan); - if (!desc) + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, + GFP_NOWAIT, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) goto err_desc_get; + lli = atdma_sg->lli; mem = sg_dma_address(sg); len = sg_dma_len(sg); @@ -1561,16 +1305,18 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, if (unlikely(mem & 3 || len & 3)) mem_width = 0; - desc->lli.saddr = mem; - desc->lli.daddr = reg; - desc->lli.ctrla = ctrla | - FIELD_PREP(ATC_SRC_WIDTH, mem_width) | - len >> mem_width; - desc->lli.ctrlb = ctrlb; - desc->len = len; + lli->saddr = mem; + lli->daddr = reg; + lli->ctrla = ctrla | + FIELD_PREP(ATC_SRC_WIDTH, mem_width) | + len >> mem_width; + lli->ctrlb = ctrlb; - atc_desc_chain(&first, &prev, desc); + atdma_sg->len = len; total_len += len; + + desc->sg[i].len = len; + atdma_lli_chain(desc, i); } break; case DMA_DEV_TO_MEM: @@ -1585,13 +1331,17 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, reg = sconfig->src_addr; for_each_sg(sgl, sg, sg_len, i) { - struct at_desc *desc; + struct atdma_sg *atdma_sg = &desc->sg[i]; + struct at_lli *lli; u32 len; u32 mem; - desc = atc_desc_get(atchan); - if (!desc) + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, + GFP_NOWAIT, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) goto err_desc_get; + lli = atdma_sg->lli; mem = sg_dma_address(sg); len = sg_dma_len(sg); @@ -1604,16 +1354,17 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, if (unlikely(mem & 3 || len & 3)) mem_width = 0; - desc->lli.saddr = reg; - desc->lli.daddr = mem; - desc->lli.ctrla = ctrla | - FIELD_PREP(ATC_DST_WIDTH, mem_width) | - len >> reg_width; - desc->lli.ctrlb = ctrlb; - desc->len = len; + lli->saddr = reg; + lli->daddr = mem; + lli->ctrla = ctrla | + FIELD_PREP(ATC_DST_WIDTH, mem_width) | + len >> reg_width; + lli->ctrlb = ctrlb; - atc_desc_chain(&first, &prev, desc); + desc->sg[i].len = len; total_len += len; + + atdma_lli_chain(desc, i); } break; default: @@ -1621,21 +1372,16 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, } /* set end-of-link to the last link descriptor of list*/ - set_desc_eol(prev); - - /* First descriptor of the chain embedds additional information */ - first->txd.cookie = -EBUSY; - first->total_len = total_len; + set_lli_eol(desc, i - 1); - /* first link descriptor of list is responsible of flags */ - first->txd.flags = flags; /* client is in control of this ack */ + desc->total_len = total_len; - return &first->txd; + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); err_desc_get: dev_err(chan2dev(chan), "not enough descriptors available\n"); err: - atc_desc_put(atchan, first); + atdma_desc_free(&desc->vd); return NULL; } @@ -1665,54 +1411,59 @@ atc_dma_cyclic_check_values(unsigned int reg_width, dma_addr_t buf_addr, */ static int atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc, - unsigned int period_index, dma_addr_t buf_addr, + unsigned int i, dma_addr_t buf_addr, unsigned int reg_width, size_t period_len, enum dma_transfer_direction direction) { + struct at_dma *atdma = to_at_dma(chan->device); struct at_dma_chan *atchan = to_at_dma_chan(chan); struct dma_slave_config *sconfig = &atchan->dma_sconfig; - u32 ctrla; + struct atdma_sg *atdma_sg = &desc->sg[i]; + struct at_lli *lli; - /* prepare common CRTLA value */ - ctrla = FIELD_PREP(ATC_SCSIZE, sconfig->src_maxburst) | - FIELD_PREP(ATC_DCSIZE, sconfig->dst_maxburst) | - FIELD_PREP(ATC_DST_WIDTH, reg_width) | - FIELD_PREP(ATC_SRC_WIDTH, reg_width) | - period_len >> reg_width; + atdma_sg->lli = dma_pool_alloc(atdma->lli_pool, GFP_ATOMIC, + &atdma_sg->lli_phys); + if (!atdma_sg->lli) + return -ENOMEM; + lli = atdma_sg->lli; switch (direction) { case DMA_MEM_TO_DEV: - desc->lli.saddr = buf_addr + (period_len * period_index); - desc->lli.daddr = sconfig->dst_addr; - desc->lli.ctrla = ctrla; - desc->lli.ctrlb = FIELD_PREP(ATC_DST_ADDR_MODE, - ATC_DST_ADDR_MODE_FIXED) | - FIELD_PREP(ATC_SRC_ADDR_MODE, - ATC_SRC_ADDR_MODE_INCR) | - FIELD_PREP(ATC_FC, ATC_FC_MEM2PER) | - FIELD_PREP(ATC_SIF, atchan->mem_if) | - FIELD_PREP(ATC_DIF, atchan->per_if); - desc->len = period_len; + lli->saddr = buf_addr + (period_len * i); + lli->daddr = sconfig->dst_addr; + lli->ctrlb = FIELD_PREP(ATC_DST_ADDR_MODE, + ATC_DST_ADDR_MODE_FIXED) | + FIELD_PREP(ATC_SRC_ADDR_MODE, + ATC_SRC_ADDR_MODE_INCR) | + FIELD_PREP(ATC_FC, ATC_FC_MEM2PER) | + FIELD_PREP(ATC_SIF, atchan->mem_if) | + FIELD_PREP(ATC_DIF, atchan->per_if); + break; case DMA_DEV_TO_MEM: - desc->lli.saddr = sconfig->src_addr; - desc->lli.daddr = buf_addr + (period_len * period_index); - desc->lli.ctrla = ctrla; - desc->lli.ctrlb = FIELD_PREP(ATC_DST_ADDR_MODE, - ATC_DST_ADDR_MODE_INCR) | - FIELD_PREP(ATC_SRC_ADDR_MODE, - ATC_SRC_ADDR_MODE_FIXED) | - FIELD_PREP(ATC_FC, ATC_FC_PER2MEM) | - FIELD_PREP(ATC_SIF, atchan->per_if) | - FIELD_PREP(ATC_DIF, atchan->mem_if); - desc->len = period_len; + lli->saddr = sconfig->src_addr; + lli->daddr = buf_addr + (period_len * i); + lli->ctrlb = FIELD_PREP(ATC_DST_ADDR_MODE, + ATC_DST_ADDR_MODE_INCR) | + FIELD_PREP(ATC_SRC_ADDR_MODE, + ATC_SRC_ADDR_MODE_FIXED) | + FIELD_PREP(ATC_FC, ATC_FC_PER2MEM) | + FIELD_PREP(ATC_SIF, atchan->per_if) | + FIELD_PREP(ATC_DIF, atchan->mem_if); break; default: return -EINVAL; } + lli->ctrla = FIELD_PREP(ATC_SCSIZE, sconfig->src_maxburst) | + FIELD_PREP(ATC_DCSIZE, sconfig->dst_maxburst) | + FIELD_PREP(ATC_DST_WIDTH, reg_width) | + FIELD_PREP(ATC_SRC_WIDTH, reg_width) | + period_len >> reg_width; + desc->sg[i].len = period_len; + return 0; } @@ -1733,8 +1484,7 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; struct dma_slave_config *sconfig = &atchan->dma_sconfig; - struct at_desc *first = NULL; - struct at_desc *prev = NULL; + struct at_desc *desc; unsigned long was_cyclic; unsigned int reg_width; unsigned int periods = buf_len / period_len; @@ -1768,33 +1518,26 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, if (atc_dma_cyclic_check_values(reg_width, buf_addr, period_len)) goto err_out; + desc = kzalloc(struct_size(desc, sg, periods), GFP_ATOMIC); + if (!desc) + goto err_out; + desc->sglen = periods; + /* 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(chan, desc, i, buf_addr, reg_width, period_len, direction)) - goto err_desc_get; - - atc_desc_chain(&first, &prev, desc); + goto err_fill_desc; + atdma_lli_chain(desc, i); } - + desc->total_len = buf_len; /* lets make a cyclic list */ - prev->lli.dscr = first->txd.phys; - - /* First descriptor of the chain embedds additional information */ - first->txd.cookie = -EBUSY; - first->total_len = buf_len; + desc->sg[i - 1].lli->dscr = desc->sg[0].lli_phys; - return &first->txd; + return vchan_tx_prep(&atchan->vc, &desc->vd, flags); -err_desc_get: - dev_err(chan2dev(chan), "not enough descriptors available\n"); - atc_desc_put(atchan, first); +err_fill_desc: + atdma_desc_free(&desc->vd); err_out: clear_bit(ATC_IS_CYCLIC, &atchan->status); return NULL; @@ -1823,17 +1566,17 @@ static int atc_pause(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - int chan_id = atchan->dma_chan.chan_id; + int chan_id = atchan->vc.chan.chan_id; unsigned long flags; dev_vdbg(chan2dev(chan), "%s\n", __func__); - spin_lock_irqsave(&atchan->lock, flags); + spin_lock_irqsave(&atchan->vc.lock, flags); dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id)); set_bit(ATC_IS_PAUSED, &atchan->status); - spin_unlock_irqrestore(&atchan->lock, flags); + spin_unlock_irqrestore(&atchan->vc.lock, flags); return 0; } @@ -1842,7 +1585,7 @@ static int atc_resume(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - int chan_id = atchan->dma_chan.chan_id; + int chan_id = atchan->vc.chan.chan_id; unsigned long flags; dev_vdbg(chan2dev(chan), "%s\n", __func__); @@ -1850,12 +1593,12 @@ static int atc_resume(struct dma_chan *chan) if (!atc_chan_is_paused(atchan)) return 0; - spin_lock_irqsave(&atchan->lock, flags); + spin_lock_irqsave(&atchan->vc.lock, flags); dma_writel(atdma, CHDR, AT_DMA_RES(chan_id)); clear_bit(ATC_IS_PAUSED, &atchan->status); - spin_unlock_irqrestore(&atchan->lock, flags); + spin_unlock_irqrestore(&atchan->vc.lock, flags); return 0; } @@ -1864,9 +1607,11 @@ static int atc_terminate_all(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - int chan_id = atchan->dma_chan.chan_id; + int chan_id = atchan->vc.chan.chan_id; unsigned long flags; + LIST_HEAD(list); + dev_vdbg(chan2dev(chan), "%s\n", __func__); /* @@ -1875,7 +1620,7 @@ static int atc_terminate_all(struct dma_chan *chan) * channel. We still have to poll the channel enable bit due * to AHB/HSB limitations. */ - spin_lock_irqsave(&atchan->lock, flags); + spin_lock_irqsave(&atchan->vc.lock, flags); /* disabling channel: must also remove suspend state */ dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask); @@ -1884,15 +1629,20 @@ static int atc_terminate_all(struct dma_chan *chan) while (dma_readl(atdma, CHSR) & atchan->mask) cpu_relax(); - /* active_list entries will end up before queued entries */ - list_splice_tail_init(&atchan->queue, &atchan->free_list); - list_splice_tail_init(&atchan->active_list, &atchan->free_list); + if (atchan->desc) { + vchan_terminate_vdesc(&atchan->desc->vd); + atchan->desc = NULL; + } + + vchan_get_all_descriptors(&atchan->vc, &list); clear_bit(ATC_IS_PAUSED, &atchan->status); /* if channel dedicated to cyclic operations, free it */ clear_bit(ATC_IS_CYCLIC, &atchan->status); - spin_unlock_irqrestore(&atchan->lock, flags); + spin_unlock_irqrestore(&atchan->vc.lock, flags); + + vchan_dma_desc_free_list(&atchan->vc, &list); return 0; } @@ -1922,9 +1672,10 @@ atc_tx_status(struct dma_chan *chan, if (dma_status == DMA_COMPLETE || !txstate) return dma_status; - spin_lock_irqsave(&atchan->lock, flags); + spin_lock_irqsave(&atchan->vc.lock, flags); + /* Get number of bytes left in the active transactions */ ret = atc_get_residue(chan, cookie, &residue); - spin_unlock_irqrestore(&atchan->lock, flags); + spin_unlock_irqrestore(&atchan->vc.lock, flags); if (unlikely(ret < 0)) { dev_vdbg(chan2dev(chan), "get residual bytes error\n"); @@ -1939,27 +1690,17 @@ atc_tx_status(struct dma_chan *chan, return dma_status; } -/** - * atc_issue_pending - takes the first transaction descriptor in the pending - * queue and starts the transfer. - * @chan: target DMA channel - */ static void atc_issue_pending(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); - struct at_desc *desc; unsigned long flags; - dev_vdbg(chan2dev(chan), "issue_pending\n"); - - spin_lock_irqsave(&atchan->lock, flags); - if (atc_chan_is_enabled(atchan) || list_empty(&atchan->queue)) - return spin_unlock_irqrestore(&atchan->lock, flags); - - desc = atc_first_queued(atchan); - list_move_tail(&desc->desc_node, &atchan->active_list); - atc_dostart(atchan, desc); - spin_unlock_irqrestore(&atchan->lock, flags); + spin_lock_irqsave(&atchan->vc.lock, flags); + if (vchan_issue_pending(&atchan->vc) && !atchan->desc) { + if (!(atc_chan_is_enabled(atchan))) + atc_dostart(atchan); + } + spin_unlock_irqrestore(&atchan->vc.lock, flags); } /** @@ -1972,9 +1713,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); - struct at_desc *desc; struct at_dma_slave *atslave; - int i; u32 cfg; dev_vdbg(chan2dev(chan), "alloc_chan_resources\n"); @@ -1985,11 +1724,6 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) return -EIO; } - if (!list_empty(&atchan->free_list)) { - dev_dbg(chan2dev(chan), "can't allocate channel resources (channel not freed from a previous use)\n"); - return -EIO; - } - cfg = ATC_DEFAULT_CFG; atslave = chan->private; @@ -2005,26 +1739,10 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) cfg = atslave->cfg; } - /* Allocate initial pool of descriptors */ - for (i = 0; i < init_nr_desc_per_channel; i++) { - desc = atc_alloc_descriptor(chan, GFP_KERNEL); - if (!desc) { - dev_err(atdma->dma_device.dev, - "Only %d initial descriptors\n", i); - break; - } - list_add_tail(&desc->desc_node, &atchan->free_list); - } - - dma_cookie_init(chan); - /* channel parameters */ channel_writel(atchan, CFG, cfg); - dev_dbg(chan2dev(chan), - "alloc_chan_resources: allocated %d descriptors\n", i); - - return i; + return 0; } /** @@ -2034,22 +1752,10 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) static void atc_free_chan_resources(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); - struct at_dma *atdma = to_at_dma(chan->device); - struct at_desc *desc, *_desc; - LIST_HEAD(list); - /* ASSERT: channel is idle */ - BUG_ON(!list_empty(&atchan->active_list)); - BUG_ON(!list_empty(&atchan->queue)); BUG_ON(atc_chan_is_enabled(atchan)); - list_for_each_entry_safe(desc, _desc, &atchan->free_list, desc_node) { - dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc); - list_del(&desc->desc_node); - /* free link descriptor */ - dma_pool_free(atdma->dma_desc_pool, desc, desc->txd.phys); - } - list_splice_init(&atchan->free_list, &list); + vchan_free_chan_resources(to_virt_chan(chan)); atchan->status = 0; /* @@ -2274,11 +1980,11 @@ static int __init at_dma_probe(struct platform_device *pdev) platform_set_drvdata(pdev, atdma); /* create a pool of consistent memory blocks for hardware descriptors */ - atdma->dma_desc_pool = dma_pool_create("at_hdmac_desc_pool", - &pdev->dev, sizeof(struct at_desc), - 4 /* word alignment */, 0); - if (!atdma->dma_desc_pool) { - dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); + atdma->lli_pool = dma_pool_create("at_hdmac_lli_pool", + &pdev->dev, sizeof(struct at_lli), + 4 /* word alignment */, 0); + if (!atdma->lli_pool) { + dev_err(&pdev->dev, "Unable to allocate DMA LLI descriptor pool\n"); err = -ENOMEM; goto err_desc_pool_create; } @@ -2303,20 +2009,13 @@ static int __init at_dma_probe(struct platform_device *pdev) atchan->mem_if = AT_DMA_MEM_IF; atchan->per_if = AT_DMA_PER_IF; - atchan->dma_chan.device = &atdma->dma_device; - dma_cookie_init(&atchan->dma_chan); - list_add_tail(&atchan->dma_chan.device_node, - &atdma->dma_device.channels); atchan->ch_regs = atdma->regs + ch_regs(i); - spin_lock_init(&atchan->lock); atchan->mask = 1 << i; - INIT_LIST_HEAD(&atchan->active_list); - INIT_LIST_HEAD(&atchan->queue); - INIT_LIST_HEAD(&atchan->free_list); - - tasklet_setup(&atchan->tasklet, atc_tasklet); + atchan->atdma = atdma; + atchan->vc.desc_free = atdma_desc_free; + vchan_init(&atchan->vc, &atdma->dma_device); atc_enable_chan_irq(atdma, i); } @@ -2390,7 +2089,7 @@ static int __init at_dma_probe(struct platform_device *pdev) err_dma_async_device_register: dma_pool_destroy(atdma->memset_pool); err_memset_pool_create: - dma_pool_destroy(atdma->dma_desc_pool); + dma_pool_destroy(atdma->lli_pool); err_desc_pool_create: free_irq(platform_get_irq(pdev, 0), atdma); err_irq: @@ -2409,17 +2108,13 @@ static int at_dma_remove(struct platform_device *pdev) dma_async_device_unregister(&atdma->dma_device); dma_pool_destroy(atdma->memset_pool); - dma_pool_destroy(atdma->dma_desc_pool); + dma_pool_destroy(atdma->lli_pool); free_irq(platform_get_irq(pdev, 0), atdma); list_for_each_entry_safe(chan, _chan, &atdma->dma_device.channels, device_node) { - struct at_dma_chan *atchan = to_at_dma_chan(chan); - /* Disable interrupts */ atc_disable_chan_irq(atdma, chan->chan_id); - - tasklet_kill(&atchan->tasklet); list_del(&chan->device_node); } @@ -2453,7 +2148,7 @@ static int at_dma_prepare(struct device *dev) static void atc_suspend_cyclic(struct at_dma_chan *atchan) { - struct dma_chan *chan = &atchan->dma_chan; + struct dma_chan *chan = &atchan->vc.chan; /* Channel should be paused by user * do it anyway even if it is not done already */ @@ -2494,7 +2189,7 @@ static int at_dma_suspend_noirq(struct device *dev) static void atc_resume_cyclic(struct at_dma_chan *atchan) { - struct at_dma *atdma = to_at_dma(atchan->dma_chan.device); + struct at_dma *atdma = to_at_dma(atchan->vc.chan.device); /* restore channel status for cyclic descriptors list: * next descriptor in the cyclic list at the time of suspend */ @@ -2568,5 +2263,6 @@ module_exit(at_dma_exit); MODULE_DESCRIPTION("Atmel AHB DMA Controller driver"); MODULE_AUTHOR("Nicolas Ferre "); +MODULE_AUTHOR("Tudor Ambarus "); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:at_hdmac");