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[209.132.180.67]) by mx.google.com with ESMTP id o189-v6si3639325pga.577.2018.07.04.09.37.05; Wed, 04 Jul 2018 09:37:19 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=LDg71GRR; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752921AbeGDQfv (ORCPT + 99 others); Wed, 4 Jul 2018 12:35:51 -0400 Received: from mail-pf0-f196.google.com ([209.85.192.196]:46138 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752260AbeGDQfs (ORCPT ); Wed, 4 Jul 2018 12:35:48 -0400 Received: by mail-pf0-f196.google.com with SMTP id l123-v6so3054830pfl.13; Wed, 04 Jul 2018 09:35:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=v4e8fr7rDuE0XOapFBXhq5NBZsBoo+Q5CGXJzi9iYLo=; b=LDg71GRR4YCUKVCHmJR3DrAoVaXoG/7pGll3d+hSOYmIu1GAiSI6fTQC+D83KcAtJR dTHM93rgCmDr/rEeBLEjMYcv50LaFuzlEEj6m83C2iQ6SILi8LoNKsXd3sWkIWdQMvCp C33/VAh5ak2Z46ShprqeMQLAJVQxguEdS273O/FBiykYWOT7h//oMcrnbpODNIY7Bvap 2mbz6pLNQmUU7BNo+4t37orvSWhja10h9BitkMOKLeTGidgYSRlrvdiiEJdWWzstK4eZ 8h0fom+y6UjAfuGWiWo95JJ2D0MQRf/QB4biC3zicNkbnUwtaWPp3vMkziDQ70ma7lev WBSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=v4e8fr7rDuE0XOapFBXhq5NBZsBoo+Q5CGXJzi9iYLo=; b=f4iukHZle7SXow3lQC3bdGoPYs+5b02gXBSwzymyEz5qAmd8Pjiq1x5oNJEf5Cd6Ns PrMU5U1UMSISKFxf4Hwwz8svmgeOcjDjQ3NIPRXytURHb2iIu2KLzIwOrYBbToLjO0JE gxReSG24ro1LiktszCYbHogMGFzAXdenwuqpOImCCbJHZFGrUfcbLsUZSt8hVek4z16n 0MBUu7urtrmML63172hFa8Ke/bD4hmdJ7+gkKVUbyIl72HB7RRBwOmyRpK1BndZNZVL0 jA2hdm35P6wYJOSpygFzLHOm+TWtstJD/LNuhrDY5lCrp1t5rPZ/GNdG9TAQ2Fu5PiVp +nnw== X-Gm-Message-State: APt69E0MrmE3AddSnClyQsGvtnCSAkMjmJEsw34w5SeLIT8ukM75Kpo5 uVoVJgyYpuBJ0rz47jFzIilm6p/DnqCkR3PwuOM= X-Received: by 2002:a62:e813:: with SMTP id c19-v6mr2889383pfi.124.1530722147978; Wed, 04 Jul 2018 09:35:47 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a17:90a:2604:0:0:0:0 with HTTP; Wed, 4 Jul 2018 09:35:47 -0700 (PDT) In-Reply-To: <20180703123214.23090-3-paul@crapouillou.net> References: <20180703123214.23090-1-paul@crapouillou.net> <20180703123214.23090-3-paul@crapouillou.net> From: PrasannaKumar Muralidharan Date: Wed, 4 Jul 2018 22:05:47 +0530 Message-ID: Subject: Re: [PATCH 02/14] dmaengine: dma-jz4780: Separate chan/ctrl registers To: Paul Cercueil Cc: Vinod Koul , Rob Herring , Mark Rutland , Ralf Baechle , Paul Burton , James Hogan , Zubair Lutfullah Kakakhel , Mathieu Malaterre , Daniel Silsby , dmaengine@vger.kernel.org, "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list , Linux-MIPS Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Paul, On 3 July 2018 at 18:02, Paul Cercueil wrote: > The register area of the JZ4780 DMA core can be split into different > sections for different purposes: > > * one set of registers is used to perform actions at the DMA core level, > that will generally affect all channels; > > * one set of registers per DMA channel, to perform actions at the DMA > channel level, that will only affect the channel in question. > > The problem rises when trying to support new versions of the JZ47xx > Ingenic SoC. For instance, the JZ4770 has two DMA cores, each one > with six DMA channels, and the register sets are interleaved: > > > By using one memory resource for the channel-specific registers and > one memory resource for the core-specific registers, we can support > the JZ4770, by initializing the driver once per DMA core with different > addresses. As per my understanding device tree should be modified only when hardware changes. This looks the other way around. It must be possible to achieve what you are trying to do in this patch without changing the device tree. > Signed-off-by: Paul Cercueil > --- > .../devicetree/bindings/dma/jz4780-dma.txt | 6 +- > drivers/dma/dma-jz4780.c | 106 +++++++++++------- > 2 files changed, 69 insertions(+), 43 deletions(-) > > diff --git a/Documentation/devicetree/bindings/dma/jz4780-dma.txt b/Documentation/devicetree/bindings/dma/jz4780-dma.txt > index f25feee62b15..f9b1864f5b77 100644 > --- a/Documentation/devicetree/bindings/dma/jz4780-dma.txt > +++ b/Documentation/devicetree/bindings/dma/jz4780-dma.txt > @@ -3,7 +3,8 @@ > Required properties: > > - compatible: Should be "ingenic,jz4780-dma" > -- reg: Should contain the DMA controller registers location and length. > +- reg: Should contain the DMA channel registers location and length, followed > + by the DMA controller registers location and length. > - interrupts: Should contain the interrupt specifier of the DMA controller. > - interrupt-parent: Should be the phandle of the interrupt controller that > - clocks: Should contain a clock specifier for the JZ4780 PDMA clock. > @@ -22,7 +23,8 @@ Example: > > dma: dma@13420000 { > compatible = "ingenic,jz4780-dma"; > - reg = <0x13420000 0x10000>; > + reg = <0x13420000 0x400 > + 0x13421000 0x40>; > > interrupt-parent = <&intc>; > interrupts = <10>; > diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c > index b40f491f0367..4d234caf5d62 100644 > --- a/drivers/dma/dma-jz4780.c > +++ b/drivers/dma/dma-jz4780.c > @@ -25,26 +25,26 @@ > #include "virt-dma.h" > > /* Global registers. */ > -#define JZ_DMA_REG_DMAC 0x1000 > -#define JZ_DMA_REG_DIRQP 0x1004 > -#define JZ_DMA_REG_DDR 0x1008 > -#define JZ_DMA_REG_DDRS 0x100c > -#define JZ_DMA_REG_DMACP 0x101c > -#define JZ_DMA_REG_DSIRQP 0x1020 > -#define JZ_DMA_REG_DSIRQM 0x1024 > -#define JZ_DMA_REG_DCIRQP 0x1028 > -#define JZ_DMA_REG_DCIRQM 0x102c > +#define JZ_DMA_REG_DMAC 0x00 > +#define JZ_DMA_REG_DIRQP 0x04 > +#define JZ_DMA_REG_DDR 0x08 > +#define JZ_DMA_REG_DDRS 0x0c > +#define JZ_DMA_REG_DMACP 0x1c > +#define JZ_DMA_REG_DSIRQP 0x20 > +#define JZ_DMA_REG_DSIRQM 0x24 > +#define JZ_DMA_REG_DCIRQP 0x28 > +#define JZ_DMA_REG_DCIRQM 0x2c > > /* Per-channel registers. */ > #define JZ_DMA_REG_CHAN(n) (n * 0x20) > -#define JZ_DMA_REG_DSA(n) (0x00 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DTA(n) (0x04 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DTC(n) (0x08 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DRT(n) (0x0c + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DCS(n) (0x10 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DCM(n) (0x14 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DDA(n) (0x18 + JZ_DMA_REG_CHAN(n)) > -#define JZ_DMA_REG_DSD(n) (0x1c + JZ_DMA_REG_CHAN(n)) > +#define JZ_DMA_REG_DSA 0x00 > +#define JZ_DMA_REG_DTA 0x04 > +#define JZ_DMA_REG_DTC 0x08 > +#define JZ_DMA_REG_DRT 0x0c > +#define JZ_DMA_REG_DCS 0x10 > +#define JZ_DMA_REG_DCM 0x14 > +#define JZ_DMA_REG_DDA 0x18 > +#define JZ_DMA_REG_DSD 0x1c > > #define JZ_DMA_DMAC_DMAE BIT(0) > #define JZ_DMA_DMAC_AR BIT(2) > @@ -140,7 +140,8 @@ enum jz_version { > > struct jz4780_dma_dev { > struct dma_device dma_device; > - void __iomem *base; > + void __iomem *chn_base; > + void __iomem *ctrl_base; > struct clk *clk; > unsigned int irq; > unsigned int nb_channels; > @@ -174,16 +175,28 @@ static inline struct jz4780_dma_dev *jz4780_dma_chan_parent( > dma_device); > } > > -static inline uint32_t jz4780_dma_readl(struct jz4780_dma_dev *jzdma, > +static inline uint32_t jz4780_dma_chn_readl(struct jz4780_dma_dev *jzdma, > + unsigned int chn, unsigned int reg) > +{ > + return readl(jzdma->chn_base + reg + JZ_DMA_REG_CHAN(chn)); > +} > + > +static inline void jz4780_dma_chn_writel(struct jz4780_dma_dev *jzdma, > + unsigned int chn, unsigned int reg, uint32_t val) > +{ > + writel(val, jzdma->chn_base + reg + JZ_DMA_REG_CHAN(chn)); > +} > + > +static inline uint32_t jz4780_dma_ctrl_readl(struct jz4780_dma_dev *jzdma, > unsigned int reg) > { > - return readl(jzdma->base + reg); > + return readl(jzdma->ctrl_base + reg); > } > > -static inline void jz4780_dma_writel(struct jz4780_dma_dev *jzdma, > +static inline void jz4780_dma_ctrl_writel(struct jz4780_dma_dev *jzdma, > unsigned int reg, uint32_t val) > { > - writel(val, jzdma->base + reg); > + writel(val, jzdma->ctrl_base + reg); > } > > static struct jz4780_dma_desc *jz4780_dma_desc_alloc( > @@ -478,17 +491,18 @@ static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) > } > > /* Use 8-word descriptors. */ > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), JZ_DMA_DCS_DES8); > + jz4780_dma_chn_writel(jzdma, jzchan->id, > + JZ_DMA_REG_DCS, JZ_DMA_DCS_DES8); > > /* Write descriptor address and initiate descriptor fetch. */ > desc_phys = jzchan->desc->desc_phys + > (jzchan->curr_hwdesc * sizeof(*jzchan->desc->desc)); > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DDA(jzchan->id), desc_phys); > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id)); > + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DDA, desc_phys); > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id)); > > /* Enable the channel. */ > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), > - JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE); > + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, > + JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE); > } > > static void jz4780_dma_issue_pending(struct dma_chan *chan) > @@ -514,7 +528,7 @@ static int jz4780_dma_terminate_all(struct dma_chan *chan) > spin_lock_irqsave(&jzchan->vchan.lock, flags); > > /* Clear the DMA status and stop the transfer. */ > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); > + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); > if (jzchan->desc) { > vchan_terminate_vdesc(&jzchan->desc->vdesc); > jzchan->desc = NULL; > @@ -563,8 +577,8 @@ static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan, > residue += desc->desc[i].dtc << jzchan->transfer_shift; > > if (next_sg != 0) { > - count = jz4780_dma_readl(jzdma, > - JZ_DMA_REG_DTC(jzchan->id)); > + count = jz4780_dma_chn_readl(jzdma, jzchan->id, > + JZ_DMA_REG_DTC); > residue += count << jzchan->transfer_shift; > } > > @@ -611,8 +625,8 @@ static void jz4780_dma_chan_irq(struct jz4780_dma_dev *jzdma, > > spin_lock(&jzchan->vchan.lock); > > - dcs = jz4780_dma_readl(jzdma, JZ_DMA_REG_DCS(jzchan->id)); > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); > + dcs = jz4780_dma_chn_readl(jzdma, jzchan->id, JZ_DMA_REG_DCS); > + jz4780_dma_chn_writel(jzdma, jzchan->id, JZ_DMA_REG_DCS, 0); > > if (dcs & JZ_DMA_DCS_AR) { > dev_warn(&jzchan->vchan.chan.dev->device, > @@ -651,7 +665,7 @@ static irqreturn_t jz4780_dma_irq_handler(int irq, void *data) > uint32_t pending, dmac; > int i; > > - pending = jz4780_dma_readl(jzdma, JZ_DMA_REG_DIRQP); > + pending = jz4780_dma_ctrl_readl(jzdma, JZ_DMA_REG_DIRQP); > > for (i = 0; i < jzdma->nb_channels; i++) { > if (!(pending & (1< @@ -661,12 +675,12 @@ static irqreturn_t jz4780_dma_irq_handler(int irq, void *data) > } > > /* Clear halt and address error status of all channels. */ > - dmac = jz4780_dma_readl(jzdma, JZ_DMA_REG_DMAC); > + dmac = jz4780_dma_ctrl_readl(jzdma, JZ_DMA_REG_DMAC); > dmac &= ~(JZ_DMA_DMAC_HLT | JZ_DMA_DMAC_AR); > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, dmac); > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC, dmac); > > /* Clear interrupt pending status. */ > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DIRQP, 0); > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DIRQP, 0); > > return IRQ_HANDLED; > } > @@ -804,9 +818,19 @@ static int jz4780_dma_probe(struct platform_device *pdev) > return -EINVAL; > } > > - jzdma->base = devm_ioremap_resource(dev, res); > - if (IS_ERR(jzdma->base)) > - return PTR_ERR(jzdma->base); > + jzdma->chn_base = devm_ioremap_resource(dev, res); > + if (IS_ERR(jzdma->chn_base)) > + return PTR_ERR(jzdma->chn_base); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + if (!res) { > + dev_err(dev, "failed to get I/O memory\n"); > + return -EINVAL; > + } > + > + jzdma->ctrl_base = devm_ioremap_resource(dev, res); > + if (IS_ERR(jzdma->ctrl_base)) > + return PTR_ERR(jzdma->ctrl_base); > > ret = platform_get_irq(pdev, 0); > if (ret < 0) { > @@ -864,9 +888,9 @@ static int jz4780_dma_probe(struct platform_device *pdev) > * Also set the FMSC bit - it increases MSC performance, so it makes > * little sense not to enable it. > */ > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC, > JZ_DMA_DMAC_DMAE | JZ_DMA_DMAC_FMSC); > - jz4780_dma_writel(jzdma, JZ_DMA_REG_DMACP, 0); > + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMACP, 0); > > INIT_LIST_HEAD(&dd->channels); > > -- > 2.18.0 > > Regards, PrasannaKumar