From patchwork Fri Sep 5 15:06:02 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 4852751 Return-Path: X-Original-To: patchwork-dmaengine@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 6CB259F2EC for ; Fri, 5 Sep 2014 15:06:29 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0622520200 for ; Fri, 5 Sep 2014 15:06:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 74A47201FB for ; Fri, 5 Sep 2014 15:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751475AbaIEPG0 (ORCPT ); Fri, 5 Sep 2014 11:06:26 -0400 Received: from mailout1.w1.samsung.com ([210.118.77.11]:31897 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751370AbaIEPGZ (ORCPT ); Fri, 5 Sep 2014 11:06:25 -0400 Received: from eucpsbgm2.samsung.com (unknown [203.254.199.245]) by mailout1.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NBF00LPHORIR6B0@mailout1.w1.samsung.com>; Fri, 05 Sep 2014 16:09:18 +0100 (BST) X-AuditID: cbfec7f5-b7f776d000003e54-62-5409d16f83ed Received: from eusync3.samsung.com ( [203.254.199.213]) by eucpsbgm2.samsung.com (EUCPMTA) with SMTP id B7.7D.15956.F61D9045; Fri, 05 Sep 2014 16:06:23 +0100 (BST) Received: from AMDC1943.digital.local ([106.116.151.171]) by eusync3.samsung.com (Oracle Communications Messaging Server 7u4-23.01(7.0.4.23.0) 64bit (built Aug 10 2011)) with ESMTPA id <0NBF00GO9OMK1090@eusync3.samsung.com>; Fri, 05 Sep 2014 16:06:23 +0100 (BST) From: Krzysztof Kozlowski To: Dan Williams , Vinod Koul , Lars-Peter Clausen , Michal Simek , Dan Carpenter , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Kyungmin Park , Marek Szyprowski , Bartlomiej Zolnierkiewicz , Krzysztof Kozlowski Subject: [RFC PATCH] dma: pl330: add Power Management support Date: Fri, 05 Sep 2014 17:06:02 +0200 Message-id: <1409929562-29583-1-git-send-email-k.kozlowski@samsung.com> X-Mailer: git-send-email 1.9.1 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrOJMWRmVeSWpSXmKPExsVy+t/xq7r5FzlDDM528VtsnLGe1eL1v+ks FtOnXmC0WD31L5D7wtDibNMbdoslk+ezWlzeNYfNYu2Ru+wW715GWLzs28/iwO2xeM9LJo8l bw6xenx8eovFo2/LKkaPz5vkPPZ+/s0SwBbFZZOSmpNZllqkb5fAldGz6CNTwX+TijPr/7A2 MD7X7mLk5JAQMJE49+gjC4QtJnHh3nq2LkYuDiGBpYwS7xc0skI4fUwS/298ZwKpYhMwlti8 fAlYlYhAK5PExXXTWUAcZoGjjBLTe9+CVQkL2Er0tS5mBrFZBFQluh5B2LwC7hILHmxmgtgn J3Hy2GTWCYzcCxgZVjGKppYmFxQnpeca6RUn5haX5qXrJefnbmKEBNbXHYxLj1kdYhTgYFTi 4e3Q5AwRYk0sK67MPcQowcGsJMJruxsoxJuSWFmVWpQfX1Sak1p8iJGJg1OqgVGb95vu8rur eS4W/TolFj7nkvqidNbq+0s9tty0dU2OPZDJPK29x41Rpt5Y1ZjH5PfU6tYyt37TPx8PfJBa 1pBxYMtp29mVrt1pt6//1uNv0lBj+OWxK2HSkr9RL6+5HVmZUMXSWaBqeqhx2U6LW/82Scv4 T3zYqzCBk285f2/u+dz0GObMGiWW4oxEQy3mouJEAFqk1/UKAgAA Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org X-Spam-Status: No, score=-8.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds both normal PM suspend/resume support and runtime PM support to pl330 DMA engine driver. The runtime power management for pl330 DMA driver allows gating of AMBA clock (PDMA) in FSYS clock domain, when the device is not processing any requests. This is necessary to enter W-AFTR low power mode on Exynos3250. The patch is based on previous work of Bartlomiej Zolnierkiewicz . Signed-off-by: Krzysztof Kozlowski --- drivers/dma/pl330.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 74 insertions(+), 4 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 66e89f04504c..bdc6ff8ee2bf 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "dmaengine.h" #define PL330_MAX_CHAN 8 @@ -1966,6 +1967,7 @@ static void pl330_tasklet(unsigned long data) struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data; struct dma_pl330_desc *desc, *_dt; unsigned long flags; + bool power_down = false; spin_lock_irqsave(&pch->lock, flags); @@ -1980,10 +1982,17 @@ static void pl330_tasklet(unsigned long data) /* Try to submit a req imm. next to the last completed cookie */ fill_queue(pch); - /* Make sure the PL330 Channel thread is active */ - spin_lock(&pch->thread->dmac->lock); - _start(pch->thread); - spin_unlock(&pch->thread->dmac->lock); + if (list_empty(&pch->work_list)) { + spin_lock(&pch->thread->dmac->lock); + _stop(pch->thread); + spin_unlock(&pch->thread->dmac->lock); + power_down = true; + } else { + /* Make sure the PL330 Channel thread is active */ + spin_lock(&pch->thread->dmac->lock); + _start(pch->thread); + spin_unlock(&pch->thread->dmac->lock); + } while (!list_empty(&pch->completed_list)) { dma_async_tx_callback callback; @@ -1998,6 +2007,12 @@ static void pl330_tasklet(unsigned long data) if (pch->cyclic) { desc->status = PREP; list_move_tail(&desc->node, &pch->work_list); + if (power_down) { + spin_lock(&pch->thread->dmac->lock); + _start(pch->thread); + spin_unlock(&pch->thread->dmac->lock); + power_down = false; + } } else { desc->status = FREE; list_move_tail(&desc->node, &pch->dmac->desc_pool); @@ -2012,6 +2027,10 @@ static void pl330_tasklet(unsigned long data) } } spin_unlock_irqrestore(&pch->lock, flags); + + /* If work list empty, power down */ + if (power_down) + pm_runtime_put(pch->dmac->ddma.dev); } bool pl330_filter(struct dma_chan *chan, void *param) @@ -2077,10 +2096,12 @@ static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned unsigned long flags; struct pl330_dmac *pl330 = pch->dmac; struct dma_slave_config *slave_config; + bool power_down = false; LIST_HEAD(list); switch (cmd) { case DMA_TERMINATE_ALL: + pm_runtime_get_sync(pl330->ddma.dev); spin_lock_irqsave(&pch->lock, flags); spin_lock(&pl330->lock); @@ -2107,10 +2128,18 @@ static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned dma_cookie_complete(&desc->txd); } + if (!list_empty(&pch->work_list)) + power_down = true; + list_splice_tail_init(&pch->submitted_list, &pl330->desc_pool); list_splice_tail_init(&pch->work_list, &pl330->desc_pool); list_splice_tail_init(&pch->completed_list, &pl330->desc_pool); spin_unlock_irqrestore(&pch->lock, flags); + pm_runtime_put(pl330->ddma.dev); + + /* If work list empty, power down */ + if (power_down) + pm_runtime_put(pl330->ddma.dev); break; case DMA_SLAVE_CONFIG: slave_config = (struct dma_slave_config *)arg; @@ -2146,6 +2175,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan) tasklet_kill(&pch->task); + pm_runtime_get_sync(pch->dmac->ddma.dev); spin_lock_irqsave(&pch->lock, flags); pl330_release_channel(pch->thread); @@ -2155,6 +2185,7 @@ static void pl330_free_chan_resources(struct dma_chan *chan) list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool); spin_unlock_irqrestore(&pch->lock, flags); + pm_runtime_put(pch->dmac->ddma.dev); } static enum dma_status @@ -2168,11 +2199,23 @@ static void pl330_issue_pending(struct dma_chan *chan) { struct dma_pl330_chan *pch = to_pchan(chan); unsigned long flags; + bool power_up; spin_lock_irqsave(&pch->lock, flags); + power_up = list_empty(&pch->work_list); list_splice_tail_init(&pch->submitted_list, &pch->work_list); spin_unlock_irqrestore(&pch->lock, flags); + if (power_up) { + /* + * Warn on nothing pending. This may break our pm_runtime + * usage counter as it is updated on work_list emptiness + * status. + */ + WARN_ON(list_empty(&pch->work_list)); + pm_runtime_get_sync(pch->dmac->ddma.dev); + } + pl330_tasklet((unsigned long)pch); } @@ -2205,6 +2248,7 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx) cookie = dma_cookie_assign(&last->txd); list_add_tail(&last->node, &pch->submitted_list); + spin_unlock_irqrestore(&pch->lock, flags); return cookie; @@ -2593,6 +2637,28 @@ static int pl330_dma_device_slave_caps(struct dma_chan *dchan, return 0; } +#ifdef CONFIG_PM_SLEEP +static int pl330_suspend(struct device *dev) +{ + struct amba_device *pcdev = to_amba_device(dev); + + if (!pm_runtime_suspended(dev)) + amba_pclk_disable(pcdev); + return 0; +} + +static int pl330_resume(struct device *dev) +{ + struct amba_device *pcdev = to_amba_device(dev); + + if (!pm_runtime_suspended(dev)) + return amba_pclk_enable(pcdev); + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(pl330_pm, pl330_suspend, pl330_resume); + static int pl330_probe(struct amba_device *adev, const struct amba_id *id) { @@ -2746,6 +2812,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) pcfg->data_buf_dep, pcfg->data_bus_width / 8, pcfg->num_chan, pcfg->num_peri, pcfg->num_events); + pm_runtime_put_noidle(&adev->dev); return 0; probe_err3: /* Idle the DMAC */ @@ -2772,6 +2839,8 @@ static int pl330_remove(struct amba_device *adev) struct pl330_dmac *pl330 = amba_get_drvdata(adev); struct dma_pl330_chan *pch, *_p; + pm_runtime_get_noresume(pl330->ddma.dev); + if (adev->dev.of_node) of_dma_controller_free(adev->dev.of_node); @@ -2810,6 +2879,7 @@ static struct amba_driver pl330_driver = { .drv = { .owner = THIS_MODULE, .name = "dma-pl330", + .pm = &pl330_pm, }, .id_table = pl330_ids, .probe = pl330_probe,