From mboxrd@z Thu Jan 1 00:00:00 1970 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 1A475C4167B for ; Wed, 28 Dec 2022 16:29:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234022AbiL1Q3r (ORCPT ); Wed, 28 Dec 2022 11:29:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233299AbiL1Q3Y (ORCPT ); Wed, 28 Dec 2022 11:29:24 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5714C1B1C8 for ; Wed, 28 Dec 2022 08:25:40 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 0C6DCB81887 for ; Wed, 28 Dec 2022 16:25:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5748BC433D2; Wed, 28 Dec 2022 16:25:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672244737; bh=4Vt7PO/WOAKdP95wWFydWytnncuro/MWNqc47PVpqCM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R5Ca+p5H4cITbo4VKlZedUTPFLWjJhDvSys2y7S6mxBk6AnKqdnibcIO9fDgR80IF DLuOafSmFHSJjyv0Y17pgov0WKf/jmdkelrc1jOoflRyOvsOn5EVKSRzovz34ys8md B5A5VySNXyNO6/b6WqC1aTElQgNyDJxhHzKgv28I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Martin=20Povi=C5=A1er?= , Vinod Koul , Sasha Levin Subject: [PATCH 6.0 0765/1073] dmaengine: apple-admac: Allocate cache SRAM to channels Date: Wed, 28 Dec 2022 15:39:13 +0100 Message-Id: <20221228144348.793642475@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144328.162723588@linuxfoundation.org> References: <20221228144328.162723588@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Martin Povišer [ Upstream commit 568aa6dd641f63166bb60d769e256789b3ac42d4 ] There's a previously unknown part of the controller interface: We have to assign SRAM carveouts to channels to store their in-flight samples in. So, obtain the size of the SRAM from a read-only register and divide it into 2K blocks for allocation to channels. The FIFO depths we configure will always fit into 2K. (This fixes audio artifacts during simultaneous playback/capture on multiple channels -- which looking back is fully accounted for by having had the caches in the DMA controller overlap in memory.) Fixes: b127315d9a78 ("dmaengine: apple-admac: Add Apple ADMAC driver") Signed-off-by: Martin Povišer Link: https://lore.kernel.org/r/20221019132324.8585-2-povik+lin@cutebit.org Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/apple-admac.c | 102 +++++++++++++++++++++++++++++++++++++- 1 file changed, 101 insertions(+), 1 deletion(-) diff --git a/drivers/dma/apple-admac.c b/drivers/dma/apple-admac.c index d69ed9c93648..e3334762be85 100644 --- a/drivers/dma/apple-admac.c +++ b/drivers/dma/apple-admac.c @@ -20,6 +20,12 @@ #define NCHANNELS_MAX 64 #define IRQ_NOUTPUTS 4 +/* + * For allocation purposes we split the cache + * memory into blocks of fixed size (given in bytes). + */ +#define SRAM_BLOCK 2048 + #define RING_WRITE_SLOT GENMASK(1, 0) #define RING_READ_SLOT GENMASK(5, 4) #define RING_FULL BIT(9) @@ -35,6 +41,9 @@ #define REG_TX_STOP 0x0004 #define REG_RX_START 0x0008 #define REG_RX_STOP 0x000c +#define REG_IMPRINT 0x0090 +#define REG_TX_SRAM_SIZE 0x0094 +#define REG_RX_SRAM_SIZE 0x0098 #define REG_CHAN_CTL(ch) (0x8000 + (ch) * 0x200) #define REG_CHAN_CTL_RST_RINGS BIT(0) @@ -52,7 +61,9 @@ #define BUS_WIDTH_FRAME_2_WORDS 0x10 #define BUS_WIDTH_FRAME_4_WORDS 0x20 -#define CHAN_BUFSIZE 0x8000 +#define REG_CHAN_SRAM_CARVEOUT(ch) (0x8050 + (ch) * 0x200) +#define CHAN_SRAM_CARVEOUT_SIZE GENMASK(31, 16) +#define CHAN_SRAM_CARVEOUT_BASE GENMASK(15, 0) #define REG_CHAN_FIFOCTL(ch) (0x8054 + (ch) * 0x200) #define CHAN_FIFOCTL_LIMIT GENMASK(31, 16) @@ -75,6 +86,8 @@ struct admac_chan { struct dma_chan chan; struct tasklet_struct tasklet; + u32 carveout; + spinlock_t lock; struct admac_tx *current_tx; int nperiod_acks; @@ -91,11 +104,23 @@ struct admac_chan { struct list_head to_free; }; +struct admac_sram { + u32 size; + /* + * SRAM_CARVEOUT has 16-bit fields, so the SRAM cannot be larger than + * 64K and a 32-bit bitfield over 2K blocks covers it. + */ + u32 allocated; +}; + struct admac_data { struct dma_device dma; struct device *dev; __iomem void *base; + struct mutex cache_alloc_lock; + struct admac_sram txcache, rxcache; + int irq; int irq_index; int nchannels; @@ -116,6 +141,60 @@ struct admac_tx { struct list_head node; }; +static int admac_alloc_sram_carveout(struct admac_data *ad, + enum dma_transfer_direction dir, + u32 *out) +{ + struct admac_sram *sram; + int i, ret = 0, nblocks; + + if (dir == DMA_MEM_TO_DEV) + sram = &ad->txcache; + else + sram = &ad->rxcache; + + mutex_lock(&ad->cache_alloc_lock); + + nblocks = sram->size / SRAM_BLOCK; + for (i = 0; i < nblocks; i++) + if (!(sram->allocated & BIT(i))) + break; + + if (i < nblocks) { + *out = FIELD_PREP(CHAN_SRAM_CARVEOUT_BASE, i * SRAM_BLOCK) | + FIELD_PREP(CHAN_SRAM_CARVEOUT_SIZE, SRAM_BLOCK); + sram->allocated |= BIT(i); + } else { + ret = -EBUSY; + } + + mutex_unlock(&ad->cache_alloc_lock); + + return ret; +} + +static void admac_free_sram_carveout(struct admac_data *ad, + enum dma_transfer_direction dir, + u32 carveout) +{ + struct admac_sram *sram; + u32 base = FIELD_GET(CHAN_SRAM_CARVEOUT_BASE, carveout); + int i; + + if (dir == DMA_MEM_TO_DEV) + sram = &ad->txcache; + else + sram = &ad->rxcache; + + if (WARN_ON(base >= sram->size)) + return; + + mutex_lock(&ad->cache_alloc_lock); + i = base / SRAM_BLOCK; + sram->allocated &= ~BIT(i); + mutex_unlock(&ad->cache_alloc_lock); +} + static void admac_modify(struct admac_data *ad, int reg, u32 mask, u32 val) { void __iomem *addr = ad->base + reg; @@ -464,15 +543,28 @@ static void admac_synchronize(struct dma_chan *chan) static int admac_alloc_chan_resources(struct dma_chan *chan) { struct admac_chan *adchan = to_admac_chan(chan); + struct admac_data *ad = adchan->host; + int ret; dma_cookie_init(&adchan->chan); + ret = admac_alloc_sram_carveout(ad, admac_chan_direction(adchan->no), + &adchan->carveout); + if (ret < 0) + return ret; + + writel_relaxed(adchan->carveout, + ad->base + REG_CHAN_SRAM_CARVEOUT(adchan->no)); return 0; } static void admac_free_chan_resources(struct dma_chan *chan) { + struct admac_chan *adchan = to_admac_chan(chan); + admac_terminate_all(chan); admac_synchronize(chan); + admac_free_sram_carveout(adchan->host, admac_chan_direction(adchan->no), + adchan->carveout); } static struct dma_chan *admac_dma_of_xlate(struct of_phandle_args *dma_spec, @@ -710,6 +802,7 @@ static int admac_probe(struct platform_device *pdev) platform_set_drvdata(pdev, ad); ad->dev = &pdev->dev; ad->nchannels = nchannels; + mutex_init(&ad->cache_alloc_lock); /* * The controller has 4 IRQ outputs. Try them all until @@ -788,6 +881,13 @@ static int admac_probe(struct platform_device *pdev) goto free_irq; } + ad->txcache.size = readl_relaxed(ad->base + REG_TX_SRAM_SIZE); + ad->rxcache.size = readl_relaxed(ad->base + REG_RX_SRAM_SIZE); + + dev_info(&pdev->dev, "Audio DMA Controller\n"); + dev_info(&pdev->dev, "imprint %x TX cache %u RX cache %u\n", + readl_relaxed(ad->base + REG_IMPRINT), ad->txcache.size, ad->rxcache.size); + return 0; free_irq: -- 2.35.1