Message ID | 1393949884-892-7-git-send-email-maxime.ripard@free-electrons.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Tue, 2014-03-04 at 17:18 +0100, Maxime Ripard wrote: > The Allwinner A31 has a 16 channels DMA controller that it shares with the > newer A23. Although sharing some similarities with the DMA controller of the > older Allwinner SoCs, it's significantly different, I don't expect it to be > possible to share the driver for these two. > > The A31 Controller is able to memory-to-memory or memory-to-device transfers on > the 16 channels in parallel. > > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > --- > .../devicetree/bindings/dma/sun6i-dma.txt | 45 + > drivers/dma/Kconfig | 8 + > drivers/dma/Makefile | 1 + > drivers/dma/sun6i-dma.c | 979 +++++++++++++++++++++ > 4 files changed, 1033 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/sun6i-dma.txt > create mode 100644 drivers/dma/sun6i-dma.c > > diff --git a/Documentation/devicetree/bindings/dma/sun6i-dma.txt b/Documentation/devicetree/bindings/dma/sun6i-dma.txt > new file mode 100644 > index 0000000..5d7c86d > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/sun6i-dma.txt > @@ -0,0 +1,45 @@ > +Allwinner A31 DMA Controller > + > +This driver follows the generic DMA bindings defined in dma.txt. > + > +Required properties: > + > +- compatible: Must be "allwinner,sun6i-a31-dma" > +- reg: Should contain the registers base address and length > +- interrupts: Should contain a reference to the interrupt used by this device > +- clocks: Should contain a reference to the parent AHB clock > +- resets: Should contain a reference to the reset controller asserting > + this device in reset > +- #dma-cells : Should be 1, a single cell holding a line request number > + > +Example: > + dma: dma-controller@01c02000 { > + compatible = "allwinner,sun6i-a31-dma"; > + reg = <0x01c02000 0x1000>; > + interrupts = <0 50 4>; > + clocks = <&ahb1_gates 6>; > + resets = <&ahb1_rst 6>; > + #dma-cells = <1>; > + }; > + > +Clients: > + > +DMA clients connected to the A31 DMA controller must use the format > +described in the dma.txt file, using a two-cell specifier for each > +channel: a phandle plus one integer cells. > +The two cells in order are: > + > +1. A phandle pointing to the DMA controller. > +2. The port ID as specified in the datasheet > + > +Example: > +spi2: spi@01c6a000 { > + compatible = "allwinner,sun6i-a31-spi"; > + reg = <0x01c6a000 0x1000>; > + interrupts = <0 67 4>; > + clocks = <&ahb1_gates 22>, <&spi2_clk>; > + clock-names = "ahb", "mod"; > + dmas = <&dma 25>, <&dma 25>; > + dma-names = "rx", "tx"; > + resets = <&ahb1_rst 22>; > +}; > diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig > index 605b016..7923697 100644 > --- a/drivers/dma/Kconfig > +++ b/drivers/dma/Kconfig > @@ -351,6 +351,14 @@ config MOXART_DMA > help > Enable support for the MOXA ART SoC DMA controller. > > +config DMA_SUN6I > + tristate "Allwinner A31 SoCs DMA support" > + depends on ARCH_SUNXI > + select DMA_ENGINE > + select DMA_VIRTUAL_CHANNELS > + help > + Support for the DMA engine for Allwinner A31 SoCs. > + > config DMA_ENGINE > bool > > diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile > index a029d0f4..18cdbad 100644 > --- a/drivers/dma/Makefile > +++ b/drivers/dma/Makefile > @@ -44,3 +44,4 @@ obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o > obj-$(CONFIG_TI_CPPI41) += cppi41.o > obj-$(CONFIG_K3_DMA) += k3dma.o > obj-$(CONFIG_MOXART_DMA) += moxart-dma.o > +obj-$(CONFIG_DMA_SUN6I) += sun6i-dma.o > diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c > new file mode 100644 > index 0000000..92cd1f3 > --- /dev/null > +++ b/drivers/dma/sun6i-dma.c > @@ -0,0 +1,979 @@ > +/* > + * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd > + * Author: Sugar <shuge@allwinnertech.com> > + * > + * Copyright (C) 2014 Maxime Ripard > + * Maxime Ripard <maxime.ripard@free-electrons.com> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/dmaengine.h> > +#include <linux/dmapool.h> > +#include <linux/interrupt.h> > +#include <linux/module.h> > +#include <linux/of_dma.h> > +#include <linux/platform_device.h> > +#include <linux/reset.h> > +#include <linux/slab.h> > +#include <linux/types.h> > + > +#include "virt-dma.h" > + > +/* > + * There's 16 physical channels that can work in parallel. > + * > + * However we have 30 different endpoints for our requests. > + * > + * Since the channels are able to handle only an unidirectional > + * transfer, we need to allocate more virtual channels so that > + * everyone can grab one channel. > + * > + * Some devices can't work in both direction (mostly because it > + * wouldn't make sense), so we have a bit fewer virtual channels than > + * 2 channels per endpoints. > + */ > + > +#define NR_MAX_CHANNELS 16 > +#define NR_MAX_REQUESTS 30 > +#define NR_MAX_VCHANS 53 > + > +/* > + * Common registers > + */ > +#define DMA_IRQ_EN(x) ((x) * 0x04) > +#define DMA_IRQ_HALF BIT(0) > +#define DMA_IRQ_PKG BIT(1) > +#define DMA_IRQ_QUEUE BIT(2) > + > +#define DMA_IRQ_CHAN_NR 8 > +#define DMA_IRQ_CHAN_WIDTH 4 > + > + > +#define DMA_IRQ_STAT(x) ((x) * 0x04 + 0x10) > + > +#define DMA_STAT 0x30 > + > +/* > + * Channels specific registers > + */ > +#define DMA_CHAN_ENABLE 0x00 > +#define DMA_CHAN_ENABLE_START BIT(0) > +#define DMA_CHAN_ENABLE_STOP 0 > + > +#define DMA_CHAN_PAUSE 0x04 > +#define DMA_CHAN_PAUSE_PAUSE BIT(1) > +#define DMA_CHAN_PAUSE_RESUME 0 > + > +#define DMA_CHAN_LLI_ADDR 0x08 > + > +#define DMA_CHAN_CUR_CFG 0x0c > +#define DMA_CHAN_CFG_SRC_DRQ(x) ((x) & 0x1f) > +#define DMA_CHAN_CFG_SRC_IO_MODE BIT(5) > +#define DMA_CHAN_CFG_SRC_LINEAR_MODE (0 << 5) > +#define DMA_CHAN_CFG_SRC_BURST(x) (((x) & 0x3) << 7) > +#define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9) > + > +#define DMA_CHAN_CFG_DST_DRQ(x) (DMA_CHAN_CFG_SRC_DRQ(x) << 16) > +#define DMA_CHAN_CFG_DST_IO_MODE (DMA_CHAN_CFG_SRC_IO_MODE << 16) > +#define DMA_CHAN_CFG_DST_LINEAR_MODE (DMA_CHAN_CFG_SRC_LINEAR_MODE << 16) > +#define DMA_CHAN_CFG_DST_BURST(x) (DMA_CHAN_CFG_SRC_BURST(x) << 16) > +#define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16) > + > +#define DMA_CHAN_CUR_SRC 0x10 > + > +#define DMA_CHAN_CUR_DST 0x14 > + > +#define DMA_CHAN_CUR_CNT 0x18 > + > +#define DMA_CHAN_CUR_PARA 0x1c > + > + > +/* > + * Various hardware related defines > + */ > +#define LLI_LAST_ITEM 0xfffff800 > +#define NORMAL_WAIT 8 > +#define DRQ_SDRAM 1 > + > +/* > + * Hardware representation of the LLI > + * > + * The hardware will be fed the physical address of this structure, > + * and read its content in order to start the transfer. > + */ > +struct sun6i_dma_lli { > + u32 cfg; > + u32 src; > + u32 dst; > + u32 len; > + u32 para; > + u32 p_lli_next; > + struct sun6i_dma_lli *v_lli_next; > +} __packed; > + > + > +struct sun6i_desc { > + struct virt_dma_desc vd; > + dma_addr_t p_lli; > + struct sun6i_dma_lli *v_lli; > +}; > + > +struct sun6i_pchan { > + u32 idx; > + void __iomem *base; > + struct sun6i_vchan *vchan; > + struct sun6i_desc *desc; > + struct sun6i_desc *done; > +}; > + > +struct sun6i_vchan { > + struct virt_dma_chan vc; > + struct list_head node; > + struct dma_slave_config cfg; > + struct sun6i_pchan *phy; > + u8 port; > +}; > + > +struct sun6i_dma_dev { > + struct dma_device slave; > + void __iomem *base; > + struct clk *clk; > + struct reset_control *rstc; > + spinlock_t lock; > + struct tasklet_struct task; > + struct list_head pending; > + struct dma_pool *pool; > + struct sun6i_pchan *pchans; > + struct sun6i_vchan *vchans; > +}; > + > +static struct device *chan2dev(struct dma_chan *chan) > +{ > + return &chan->dev->device; > +} > + > +static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d) > +{ > + return container_of(d, struct sun6i_dma_dev, slave); > +} > + > +static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan) > +{ > + return container_of(chan, struct sun6i_vchan, vc.chan); > +} > + > +static inline struct sun6i_desc * > +to_sun6i_desc(struct dma_async_tx_descriptor *tx) > +{ > + return container_of(tx, struct sun6i_desc, vd.tx); > +} > + > +static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev) > +{ > + dev_dbg(sdev->slave.dev, "Common register:\n" > + "\tmask0(%04x): 0x%08x\n" > + "\tmask1(%04x): 0x%08x\n" > + "\tpend0(%04x): 0x%08x\n" > + "\tpend1(%04x): 0x%08x\n" > + "\tstats(%04x): 0x%08x\n", > + DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)), > + DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)), > + DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)), > + DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)), > + DMA_STAT, readl(sdev->base + DMA_STAT)); > +} > + > +static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev, > + struct sun6i_pchan *pchan) > +{ > + dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n" > + "\t___en(%04x): \t0x%08x\n" > + "\tpause(%04x): \t0x%08x\n" > + "\tstart(%04x): \t0x%08x\n" > + "\t__cfg(%04x): \t0x%08x\n" > + "\t__src(%04x): \t0x%08x\n" > + "\t__dst(%04x): \t0x%08x\n" > + "\tcount(%04x): \t0x%08x\n" > + "\t_para(%04x): \t0x%08x\n\n", > + pchan->idx, __virt_to_phys((unsigned long)pchan->base), > + DMA_CHAN_ENABLE, > + readl(pchan->base + DMA_CHAN_ENABLE), > + DMA_CHAN_PAUSE, > + readl(pchan->base + DMA_CHAN_PAUSE), > + DMA_CHAN_LLI_ADDR, > + readl(pchan->base + DMA_CHAN_LLI_ADDR), > + DMA_CHAN_CUR_CFG, > + readl(pchan->base + DMA_CHAN_CUR_CFG), > + DMA_CHAN_CUR_SRC, > + readl(pchan->base + DMA_CHAN_CUR_SRC), > + DMA_CHAN_CUR_DST, > + readl(pchan->base + DMA_CHAN_CUR_DST), > + DMA_CHAN_CUR_CNT, > + readl(pchan->base + DMA_CHAN_CUR_CNT), > + DMA_CHAN_CUR_PARA, > + readl(pchan->base + DMA_CHAN_CUR_PARA)); > +} > + > +static inline u8 convert_burst(u8 maxburst) > +{ > + if (maxburst == 1 || maxburst > 16) > + return 0; > + > + return fls(maxburst) - 1; > +} > + > +static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width) > +{ > + switch (addr_width) { > + case DMA_SLAVE_BUSWIDTH_2_BYTES: > + return 1; > + case DMA_SLAVE_BUSWIDTH_4_BYTES: > + return 2; > + default: > + return 0; > + } > +} > + > +static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev, > + struct sun6i_dma_lli *next, > + dma_addr_t next_phy, > + struct sun6i_desc *txd) > +{ > + if ((!prev && !txd) || !next) > + return NULL; > + > + if (!prev) { > + txd->p_lli = next_phy; > + txd->v_lli = next; > + } else { > + prev->p_lli_next = next_phy; > + prev->v_lli_next = next; > + } > + > + next->p_lli_next = LLI_LAST_ITEM; > + next->v_lli_next = NULL; > + > + return next; > +} > + > +static inline void sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, > + dma_addr_t src, > + dma_addr_t dst, u32 len, > + struct dma_slave_config *config) > +{ > + u32 src_width, dst_width, src_burst, dst_burst; > + > + if (!config) > + return; > + > + src_burst = convert_burst(config->src_maxburst); > + dst_burst = convert_burst(config->dst_maxburst); > + > + src_width = convert_buswidth(config->src_addr_width); > + dst_width = convert_buswidth(config->dst_addr_width); > + > + lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) | > + DMA_CHAN_CFG_SRC_WIDTH(src_width) | > + DMA_CHAN_CFG_DST_BURST(dst_burst) | > + DMA_CHAN_CFG_DST_WIDTH(dst_width); > + > + lli->src = src; > + lli->dst = dst; > + lli->len = len; > + lli->para = NORMAL_WAIT; > + > +} > + > +static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan, > + struct sun6i_dma_lli *lli) > +{ > + dev_dbg(chan2dev(&vchan->vc.chan), > + "\n\tdesc: p - %pa v - 0x%08x\n" > + "\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n" > + "\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n", > + __virt_to_phys((unsigned long)lli), (u32)lli, > + lli->cfg, lli->src, lli->dst, > + lli->len, lli->para, lli->p_lli_next); > +} > + > +static void sun6i_dma_free_desc(struct virt_dma_desc *vd) > +{ > + struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device); > + struct sun6i_dma_lli *v_lli, *v_next; > + dma_addr_t p_lli, p_next; > + > + if (unlikely(!txd)) > + return; > + > + p_lli = txd->p_lli; > + v_lli = txd->v_lli; > + > + while (v_lli) { > + v_next = v_lli->v_lli_next; > + p_next = v_lli->p_lli_next; > + > + dma_pool_free(sdev->pool, v_lli, p_lli); > + > + v_lli = v_next; > + p_lli = p_next; > + } > + > + kfree(txd); > +} > + > +static int sun6i_dma_terminate_all(struct sun6i_vchan *vchan) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); > + struct sun6i_pchan *pchan = vchan->phy; > + unsigned long flags; > + LIST_HEAD(head); > + > + spin_lock(&sdev->lock); > + list_del_init(&vchan->node); > + spin_unlock(&sdev->lock); > + > + spin_lock_irqsave(&vchan->vc.lock, flags); > + > + vchan_get_all_descriptors(&vchan->vc, &head); > + > + if (pchan) { > + writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE); > + writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE); > + > + vchan->phy = NULL; > + pchan->vchan = NULL; > + pchan->desc = NULL; > + pchan->done = NULL; > + } > + > + spin_unlock_irqrestore(&vchan->vc.lock, flags); > + > + vchan_dma_desc_free_list(&vchan->vc, &head); > + > + return 0; > +} > + > +static int sun6i_dma_start_desc(struct sun6i_vchan *vchan) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); > + struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc); > + struct sun6i_pchan *pchan = vchan->phy; > + u32 irq_val, irq_reg, irq_offset; > + > + if (!pchan) > + return -EAGAIN; > + > + if (!desc) { > + pchan->desc = NULL; > + pchan->done = NULL; > + return -EAGAIN; > + } > + > + list_del(&desc->node); > + > + pchan->desc = to_sun6i_desc(&desc->tx); > + pchan->done = NULL; > + > + sun6i_dma_dump_lli(vchan, pchan->desc->v_lli); > + > + irq_reg = pchan->idx / DMA_IRQ_CHAN_NR; > + irq_offset = pchan->idx % DMA_IRQ_CHAN_NR; > + > + irq_val = readl(sdev->base + DMA_IRQ_EN(irq_offset)); > + irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH); > + writel(irq_val, sdev->base + DMA_IRQ_EN(irq_offset)); > + > + writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR); > + writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE); > + > + sun6i_dma_dump_com_regs(sdev); > + sun6i_dma_dump_chan_regs(sdev, pchan); > + > + return 0; > +} > + > +static void sun6i_dma_tasklet(unsigned long data) > +{ > + struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data; > + struct sun6i_vchan *vchan; > + struct sun6i_pchan *pchan; > + unsigned int pchan_alloc = 0; > + unsigned int pchan_idx; > + > + list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) { > + spin_lock_irq(&vchan->vc.lock); > + > + pchan = vchan->phy; > + > + if (pchan && pchan->done) { > + if (sun6i_dma_start_desc(vchan)) { > + /* > + * No current txd associated with this channel > + */ > + dev_dbg(sdev->slave.dev, "pchan %u: free\n", > + pchan->idx); > + > + /* Mark this channel free */ > + vchan->phy = NULL; > + pchan->vchan = NULL; > + } > + } > + spin_unlock_irq(&vchan->vc.lock); > + } > + > + spin_lock_irq(&sdev->lock); > + for (pchan_idx = 0; pchan_idx < NR_MAX_CHANNELS; pchan_idx++) { > + pchan = &sdev->pchans[pchan_idx]; > + > + if (pchan->vchan == NULL && !list_empty(&sdev->pending)) { > + vchan = list_first_entry(&sdev->pending, > + struct sun6i_vchan, node); > + > + /* Remove from pending channels */ > + list_del_init(&vchan->node); > + pchan_alloc |= BIT(pchan_idx); > + > + /* Mark this channel allocated */ > + pchan->vchan = vchan; > + vchan->phy = pchan; > + dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n", > + pchan->idx, &vchan->vc); > + } > + } > + spin_unlock_irq(&sdev->lock); > + > + for (pchan_idx = 0; pchan_idx < NR_MAX_CHANNELS; pchan_idx++) { > + if (pchan_alloc & BIT(pchan_idx)) { > + pchan = sdev->pchans + pchan_idx; > + vchan = pchan->vchan; > + if (vchan) { > + spin_lock_irq(&vchan->vc.lock); > + sun6i_dma_start_desc(vchan); > + spin_unlock_irq(&vchan->vc.lock); > + } > + } > + } > +} > + > +static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id) > +{ > + struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)dev_id; Unneeded explicit casting. > + struct sun6i_vchan *vchan; > + struct sun6i_pchan *pchan; > + int i, j, ret = IRQ_NONE; > + u32 status; > + > + for (i = 0; i < 2; i++) { > + status = readl(sdev->base + DMA_IRQ_STAT(i)); > + if (!status) > + continue; > + > + dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n", > + i ? "high" : "low", status); > + > + writel(status, sdev->base + DMA_IRQ_STAT(i)); > + > + for (j = 0; (j < 8) && status; j++) { > + if (status & DMA_IRQ_QUEUE) { > + pchan = sdev->pchans + j; > + vchan = pchan->vchan; > + > + if (vchan) { > + unsigned long flags; > + > + spin_lock_irqsave(&vchan->vc.lock, > + flags); > + vchan_cookie_complete(&pchan->desc->vd); > + pchan->done = pchan->desc; > + spin_unlock_irqrestore(&vchan->vc.lock, > + flags); > + } > + } > + > + status = status >> 4; > + } > + > + tasklet_schedule(&sdev->task); > + ret = IRQ_HANDLED; > + } > + > + return ret; > +} > + > +static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy( > + struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, > + size_t len, unsigned long flags) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + struct dma_slave_config *sconfig = &vchan->cfg; > + struct sun6i_dma_lli *v_lli; > + struct sun6i_desc *txd; > + dma_addr_t p_lli; > + > + dev_dbg(chan2dev(chan), > + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", > + __func__, vchan->vc.chan.chan_id, dest, src, len, flags); &desc, &src %pa[d] use a reference. Please, recheck your code. > + > + if (!len) > + return NULL; > + > + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); > + if (!txd) > + return NULL; > + > + v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); > + if (!v_lli) { > + dev_err(sdev->slave.dev, "Failed to alloc lli memory\n"); > + kfree(txd); > + return NULL; > + } > + > + sun6i_dma_cfg_lli(v_lli, src, dest, len, sconfig); > + v_lli->cfg |= DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | > + DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | > + DMA_CHAN_CFG_DST_LINEAR_MODE | > + DMA_CHAN_CFG_SRC_LINEAR_MODE; > + > + sun6i_dma_lli_add(NULL, v_lli, p_lli, txd); > + > + sun6i_dma_dump_lli(vchan, v_lli); > + > + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); > +} > + > +static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( > + struct dma_chan *chan, struct scatterlist *sgl, > + unsigned int sg_len, enum dma_transfer_direction dir, > + unsigned long flags, void *context) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + struct dma_slave_config *sconfig = &vchan->cfg; > + struct sun6i_dma_lli *v_lli, *prev = NULL; > + struct sun6i_desc *txd; > + struct scatterlist *sg; > + dma_addr_t p_lli; > + int i; > + > + if (!sgl) > + return NULL; > + > + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); > + if (!txd) > + return NULL; > + > + for_each_sg(sgl, sg, sg_len, i) { > + v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); > + if (!v_lli) { > + kfree(txd); > + return NULL; > + } > + > + if (dir == DMA_MEM_TO_DEV) { > + sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg), > + sconfig->dst_addr, sg_dma_len(sg), > + sconfig); > + v_lli->cfg |= DMA_CHAN_CFG_DST_IO_MODE | > + DMA_CHAN_CFG_SRC_LINEAR_MODE | > + DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | > + DMA_CHAN_CFG_DST_DRQ(vchan->port); > + > + dev_dbg(chan2dev(chan), > + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", > + __func__, vchan->vc.chan.chan_id, > + sconfig->dst_addr, sg_dma_address(sg), > + sg_dma_len(sg), flags); > + > + } else if (dir == DMA_DEV_TO_MEM) { > + sun6i_dma_cfg_lli(v_lli, sconfig->src_addr, > + sg_dma_address(sg), sg_dma_len(sg), > + sconfig); > + v_lli->cfg |= DMA_CHAN_CFG_DST_LINEAR_MODE | > + DMA_CHAN_CFG_SRC_IO_MODE | > + DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | > + DMA_CHAN_CFG_SRC_DRQ(vchan->port); > + > + dev_dbg(chan2dev(chan), > + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", > + __func__, vchan->vc.chan.chan_id, > + sg_dma_address(sg), sconfig->src_addr, > + sg_dma_len(sg), flags); > + } If direction is not slave, you may end up here with undefined values. At the beginning of this function you probably can do something like if (!is_slave_direction()) { dev_err("Wrong direction"); return -EINVAL; } ...and remove second if() in the condition. > + > + prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd); > + } > + > +#ifdef DEBUG > + dev_dbg(chan2dev(chan), "First: %pad\n", txd->p_lli); > + for (prev = txd->v_lli; prev != NULL; prev = prev->v_lli_next) > + sun6i_dma_dump_lli(vchan, prev); > +#endif > + > + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); > +} > + > +static int sun6i_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, > + unsigned long arg) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + struct sun6i_pchan *pchan = vchan->phy; > + unsigned long flags; > + int ret = 0; > + > + switch (cmd) { > + case DMA_RESUME: > + dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc); > + > + spin_lock_irqsave(&vchan->vc.lock, flags); > + > + if (pchan) { > + writel(DMA_CHAN_PAUSE_RESUME, > + pchan->base + DMA_CHAN_PAUSE); > + } else if (!list_empty(&vchan->vc.desc_issued)) { > + spin_lock(&sdev->lock); > + list_add_tail(&vchan->node, &sdev->pending); > + spin_unlock(&sdev->lock); > + } > + > + spin_unlock_irqrestore(&vchan->vc.lock, flags); > + break; > + > + case DMA_PAUSE: > + dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc); > + > + if (pchan) { > + writel(DMA_CHAN_PAUSE_PAUSE, > + pchan->base + DMA_CHAN_PAUSE); > + } else { > + spin_lock(&sdev->lock); > + list_del_init(&vchan->node); > + spin_unlock(&sdev->lock); > + } > + break; > + > + case DMA_TERMINATE_ALL: > + ret = sun6i_dma_terminate_all(vchan); > + break; > + case DMA_SLAVE_CONFIG: > + memcpy(&vchan->cfg, (struct dma_slave_config *)arg, > + sizeof(struct dma_slave_config)); > + break; > + default: > + ret = -ENXIO; > + break; > + } > + return ret; > +} > + > +static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan, > + dma_cookie_t cookie, > + struct dma_tx_state *state) > +{ > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + struct sun6i_pchan *pchan = vchan->phy; > + struct sun6i_dma_lli *lli; > + struct virt_dma_desc *vd; > + struct sun6i_desc *txd; > + enum dma_status ret; > + unsigned long flags; > + size_t bytes = 0; > + > + ret = dma_cookie_status(chan, cookie, state); > + if (ret == DMA_COMPLETE) > + return ret; > + > + spin_lock_irqsave(&vchan->vc.lock, flags); > + > + vd = vchan_find_desc(&vchan->vc, cookie); > + txd = to_sun6i_desc(&vd->tx); > + > + if (vd) { > + for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next) > + bytes += lli->len; > + } else if (!pchan || !pchan->desc) { > + bytes = 0; > + } else { > + bytes = readl(pchan->base + DMA_CHAN_CUR_CNT); > + } > + > + spin_unlock_irqrestore(&vchan->vc.lock, flags); > + > + dma_set_residue(state, bytes); > + > + return ret; > +} > + > +static void sun6i_dma_issue_pending(struct dma_chan *chan) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + unsigned long flags; > + > + spin_lock_irqsave(&vchan->vc.lock, flags); > + > + if (vchan_issue_pending(&vchan->vc)) { > + spin_lock(&sdev->lock); > + > + if (!vchan->phy) { > + if (list_empty(&vchan->node)) { if (cond1) { if (cond2) { }} usually can be converted to if (cond1 && cond2) {} > + list_add_tail(&vchan->node, &sdev->pending); > + tasklet_schedule(&sdev->task); > + dev_dbg(chan2dev(chan), "vchan %p: issued\n", > + &vchan->vc); > + } > + } > + > + spin_unlock(&sdev->lock); > + } else { > + dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n", > + &vchan->vc); > + } > + > + spin_unlock_irqrestore(&vchan->vc.lock, flags); > +} > + > +static int sun6i_dma_alloc_chan_resources(struct dma_chan *chan) > +{ > + return 0; > +} > + > +static void sun6i_dma_free_chan_resources(struct dma_chan *chan) > +{ > + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); > + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); > + unsigned long flags; > + > + spin_lock_irqsave(&sdev->lock, flags); > + list_del_init(&vchan->node); > + spin_unlock_irqrestore(&sdev->lock, flags); > + > + vchan_free_chan_resources(&vchan->vc); > +} > + > +static inline void sun6i_dma_free(struct sun6i_dma_dev *sdc) > +{ > + int i; > + > + for (i = 0; i < NR_MAX_VCHANS; i++) { > + struct sun6i_vchan *vchan = &sdc->vchans[i]; > + > + list_del(&vchan->vc.chan.device_node); > + tasklet_kill(&vchan->vc.task); > + } > + > + tasklet_kill(&sdc->task); > +} > + > +static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec, > + struct of_dma *ofdma) > +{ > + struct sun6i_dma_dev *sdev = ofdma->of_dma_data; > + struct sun6i_vchan *vchan; > + struct dma_chan *chan; > + u8 port = dma_spec->args[0]; > + > + if (port > NR_MAX_REQUESTS) > + return NULL; > + > + chan = dma_get_any_slave_channel(&sdev->slave); > + if (!chan) > + return NULL; > + > + vchan = to_sun6i_vchan(chan); > + vchan->port = port; > + > + return chan; > +} > + > +static int sun6i_dma_probe(struct platform_device *pdev) > +{ > + struct sun6i_dma_dev *sdc; > + struct resource *res; > + struct clk *mux, *pll6; > + int irq; > + int ret, i; > + > + sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL); > + if (!sdc) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + sdc->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(sdc->base)) > + return PTR_ERR(sdc->base); > + > + irq = platform_get_irq(pdev, 0); > + ret = devm_request_irq(&pdev->dev, irq, sun6i_dma_interrupt, 0, > + dev_name(&pdev->dev), sdc); > + if (ret) { > + dev_err(&pdev->dev, "Cannot request IRQ\n"); > + return ret; > + } > + > + sdc->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(sdc->clk)) { > + dev_err(&pdev->dev, "No clock specified\n"); > + return PTR_ERR(sdc->clk); > + } > + > + mux = devm_clk_get(&pdev->dev, "ahb1_mux"); > + if (IS_ERR(mux)) { > + pr_err("Couldn't get AHB1 Mux\n"); dev_err() > + return PTR_ERR(mux); > + } > + > + pll6 = devm_clk_get(&pdev->dev, "pll6"); > + if (IS_ERR(pll6)) { > + pr_err("Couldn't get PLL6\n"); Ditto. > + return PTR_ERR(pll6); > + } > + > + ret = clk_set_parent(mux, pll6); > + if (ret) { > + dev_err(&pdev->dev, "Couldn't reparent AHB1 on PLL6\n"); > + return ret; > + } > + > + devm_clk_put(&pdev->dev, mux); > + devm_clk_put(&pdev->dev, pll6); Since you put those here, would it be better to use plain clk_get/clk_put ? > + > + sdc->rstc = devm_reset_control_get(&pdev->dev, NULL); > + if (IS_ERR(sdc->rstc)) { > + dev_err(&pdev->dev, "No reset controller specified\n"); > + return PTR_ERR(sdc->rstc); > + } > + > + sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev, > + sizeof(struct sun6i_dma_lli), 4, 0); > + if (!sdc->pool) { > + dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); > + return -ENOMEM; > + } > + > + platform_set_drvdata(pdev, sdc); > + INIT_LIST_HEAD(&sdc->pending); > + spin_lock_init(&sdc->lock); > + > + dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask); > + dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask); > + dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask); > + > + INIT_LIST_HEAD(&sdc->slave.channels); > + sdc->slave.device_alloc_chan_resources = sun6i_dma_alloc_chan_resources; > + sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources; > + sdc->slave.device_tx_status = sun6i_dma_tx_status; > + sdc->slave.device_issue_pending = sun6i_dma_issue_pending; > + sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg; > + sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy; > + sdc->slave.device_control = sun6i_dma_control; > + sdc->slave.chancnt = NR_MAX_VCHANS; > + > + sdc->slave.dev = &pdev->dev; > + > + sdc->pchans = devm_kcalloc(&pdev->dev, NR_MAX_CHANNELS, > + sizeof(struct sun6i_pchan), GFP_KERNEL); > + if (!sdc->pchans) > + return -ENOMEM; > + > + sdc->vchans = devm_kcalloc(&pdev->dev, NR_MAX_VCHANS, > + sizeof(struct sun6i_vchan), GFP_KERNEL); > + if (!sdc->vchans) > + return -ENOMEM; > + > + tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc); > + > + for (i = 0; i < NR_MAX_CHANNELS; i++) { > + struct sun6i_pchan *pchan = &sdc->pchans[i]; > + > + pchan->idx = i; > + pchan->base = sdc->base + 0x100 + i * 0x40; > + } > + > + for (i = 0; i < NR_MAX_VCHANS; i++) { > + struct sun6i_vchan *vchan = &sdc->vchans[i]; > + > + INIT_LIST_HEAD(&vchan->node); > + vchan->vc.desc_free = sun6i_dma_free_desc; > + vchan_init(&vchan->vc, &sdc->slave); > + } > + > + ret = reset_control_deassert(sdc->rstc); > + if (ret) { > + dev_err(&pdev->dev, "Couldn't deassert the device from reset\n"); > + goto err_chan_free; > + } > + > + ret = clk_prepare_enable(sdc->clk); > + if (ret) { > + dev_err(&pdev->dev, "Couldn't enable the clock\n"); > + goto err_reset_assert; > + } > + > + ret = dma_async_device_register(&sdc->slave); > + if (ret) { > + dev_warn(&pdev->dev, "Failed to register DMA engine device\n"); > + goto err_clk_disable; > + } > + > + ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate, > + sdc); > + if (ret) { > + dev_err(&pdev->dev, "of_dma_controller_register failed\n"); > + goto err_dma_unregister; > + } > + > + return 0; > + > +err_dma_unregister: > + dma_async_device_unregister(&sdc->slave); > +err_clk_disable: > + clk_disable_unprepare(sdc->clk); > +err_reset_assert: > + reset_control_assert(sdc->rstc); > +err_chan_free: > + sun6i_dma_free(sdc); > + return ret; > +} > + > +static int sun6i_dma_remove(struct platform_device *pdev) > +{ > + struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev); > + > + of_dma_controller_free(pdev->dev.of_node); > + dma_async_device_unregister(&sdc->slave); > + > + clk_disable_unprepare(sdc->clk); > + reset_control_assert(sdc->rstc); > + > + sun6i_dma_free(sdc); > + > + return 0; > +} > + > +static struct of_device_id sun6i_dma_match[] = { > + { .compatible = "allwinner,sun6i-a31-dma" } > +}; > + > +static struct platform_driver sun6i_dma_driver = { > + .probe = sun6i_dma_probe, > + .remove = sun6i_dma_remove, > + .driver = { > + .name = "sun6i-dma", > + .of_match_table = sun6i_dma_match, > + }, > +}; > +module_platform_driver(sun6i_dma_driver); > + > +MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver"); > +MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>"); > +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); > +MODULE_LICENSE("GPL");
Hi Andriy, On Wed, Mar 05, 2014 at 02:07:55PM +0000, Shevchenko, Andriy wrote: > > + return PTR_ERR(pll6); > > + } > > + > > + ret = clk_set_parent(mux, pll6); > > + if (ret) { > > + dev_err(&pdev->dev, "Couldn't reparent AHB1 on PLL6\n"); > > + return ret; > > + } > > + > > + devm_clk_put(&pdev->dev, mux); > > + devm_clk_put(&pdev->dev, pll6); > > Since you put those here, would it be better to use plain > clk_get/clk_put ? Actually, this allows to have no exit path for the case where one of the calls between the first clk_get, and here. devm_clk_* makes error handling much easier here, that's just all I'll fix the other comments you had, and send a new version. Thanks! Maxime
diff --git a/Documentation/devicetree/bindings/dma/sun6i-dma.txt b/Documentation/devicetree/bindings/dma/sun6i-dma.txt new file mode 100644 index 0000000..5d7c86d --- /dev/null +++ b/Documentation/devicetree/bindings/dma/sun6i-dma.txt @@ -0,0 +1,45 @@ +Allwinner A31 DMA Controller + +This driver follows the generic DMA bindings defined in dma.txt. + +Required properties: + +- compatible: Must be "allwinner,sun6i-a31-dma" +- reg: Should contain the registers base address and length +- interrupts: Should contain a reference to the interrupt used by this device +- clocks: Should contain a reference to the parent AHB clock +- resets: Should contain a reference to the reset controller asserting + this device in reset +- #dma-cells : Should be 1, a single cell holding a line request number + +Example: + dma: dma-controller@01c02000 { + compatible = "allwinner,sun6i-a31-dma"; + reg = <0x01c02000 0x1000>; + interrupts = <0 50 4>; + clocks = <&ahb1_gates 6>; + resets = <&ahb1_rst 6>; + #dma-cells = <1>; + }; + +Clients: + +DMA clients connected to the A31 DMA controller must use the format +described in the dma.txt file, using a two-cell specifier for each +channel: a phandle plus one integer cells. +The two cells in order are: + +1. A phandle pointing to the DMA controller. +2. The port ID as specified in the datasheet + +Example: +spi2: spi@01c6a000 { + compatible = "allwinner,sun6i-a31-spi"; + reg = <0x01c6a000 0x1000>; + interrupts = <0 67 4>; + clocks = <&ahb1_gates 22>, <&spi2_clk>; + clock-names = "ahb", "mod"; + dmas = <&dma 25>, <&dma 25>; + dma-names = "rx", "tx"; + resets = <&ahb1_rst 22>; +}; diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 605b016..7923697 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -351,6 +351,14 @@ config MOXART_DMA help Enable support for the MOXA ART SoC DMA controller. +config DMA_SUN6I + tristate "Allwinner A31 SoCs DMA support" + depends on ARCH_SUNXI + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Support for the DMA engine for Allwinner A31 SoCs. + config DMA_ENGINE bool diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index a029d0f4..18cdbad 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -44,3 +44,4 @@ obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o obj-$(CONFIG_TI_CPPI41) += cppi41.o obj-$(CONFIG_K3_DMA) += k3dma.o obj-$(CONFIG_MOXART_DMA) += moxart-dma.o +obj-$(CONFIG_DMA_SUN6I) += sun6i-dma.o diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c new file mode 100644 index 0000000..92cd1f3 --- /dev/null +++ b/drivers/dma/sun6i-dma.c @@ -0,0 +1,979 @@ +/* + * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd + * Author: Sugar <shuge@allwinnertech.com> + * + * Copyright (C) 2014 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dmapool.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/reset.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include "virt-dma.h" + +/* + * There's 16 physical channels that can work in parallel. + * + * However we have 30 different endpoints for our requests. + * + * Since the channels are able to handle only an unidirectional + * transfer, we need to allocate more virtual channels so that + * everyone can grab one channel. + * + * Some devices can't work in both direction (mostly because it + * wouldn't make sense), so we have a bit fewer virtual channels than + * 2 channels per endpoints. + */ + +#define NR_MAX_CHANNELS 16 +#define NR_MAX_REQUESTS 30 +#define NR_MAX_VCHANS 53 + +/* + * Common registers + */ +#define DMA_IRQ_EN(x) ((x) * 0x04) +#define DMA_IRQ_HALF BIT(0) +#define DMA_IRQ_PKG BIT(1) +#define DMA_IRQ_QUEUE BIT(2) + +#define DMA_IRQ_CHAN_NR 8 +#define DMA_IRQ_CHAN_WIDTH 4 + + +#define DMA_IRQ_STAT(x) ((x) * 0x04 + 0x10) + +#define DMA_STAT 0x30 + +/* + * Channels specific registers + */ +#define DMA_CHAN_ENABLE 0x00 +#define DMA_CHAN_ENABLE_START BIT(0) +#define DMA_CHAN_ENABLE_STOP 0 + +#define DMA_CHAN_PAUSE 0x04 +#define DMA_CHAN_PAUSE_PAUSE BIT(1) +#define DMA_CHAN_PAUSE_RESUME 0 + +#define DMA_CHAN_LLI_ADDR 0x08 + +#define DMA_CHAN_CUR_CFG 0x0c +#define DMA_CHAN_CFG_SRC_DRQ(x) ((x) & 0x1f) +#define DMA_CHAN_CFG_SRC_IO_MODE BIT(5) +#define DMA_CHAN_CFG_SRC_LINEAR_MODE (0 << 5) +#define DMA_CHAN_CFG_SRC_BURST(x) (((x) & 0x3) << 7) +#define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9) + +#define DMA_CHAN_CFG_DST_DRQ(x) (DMA_CHAN_CFG_SRC_DRQ(x) << 16) +#define DMA_CHAN_CFG_DST_IO_MODE (DMA_CHAN_CFG_SRC_IO_MODE << 16) +#define DMA_CHAN_CFG_DST_LINEAR_MODE (DMA_CHAN_CFG_SRC_LINEAR_MODE << 16) +#define DMA_CHAN_CFG_DST_BURST(x) (DMA_CHAN_CFG_SRC_BURST(x) << 16) +#define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16) + +#define DMA_CHAN_CUR_SRC 0x10 + +#define DMA_CHAN_CUR_DST 0x14 + +#define DMA_CHAN_CUR_CNT 0x18 + +#define DMA_CHAN_CUR_PARA 0x1c + + +/* + * Various hardware related defines + */ +#define LLI_LAST_ITEM 0xfffff800 +#define NORMAL_WAIT 8 +#define DRQ_SDRAM 1 + +/* + * Hardware representation of the LLI + * + * The hardware will be fed the physical address of this structure, + * and read its content in order to start the transfer. + */ +struct sun6i_dma_lli { + u32 cfg; + u32 src; + u32 dst; + u32 len; + u32 para; + u32 p_lli_next; + struct sun6i_dma_lli *v_lli_next; +} __packed; + + +struct sun6i_desc { + struct virt_dma_desc vd; + dma_addr_t p_lli; + struct sun6i_dma_lli *v_lli; +}; + +struct sun6i_pchan { + u32 idx; + void __iomem *base; + struct sun6i_vchan *vchan; + struct sun6i_desc *desc; + struct sun6i_desc *done; +}; + +struct sun6i_vchan { + struct virt_dma_chan vc; + struct list_head node; + struct dma_slave_config cfg; + struct sun6i_pchan *phy; + u8 port; +}; + +struct sun6i_dma_dev { + struct dma_device slave; + void __iomem *base; + struct clk *clk; + struct reset_control *rstc; + spinlock_t lock; + struct tasklet_struct task; + struct list_head pending; + struct dma_pool *pool; + struct sun6i_pchan *pchans; + struct sun6i_vchan *vchans; +}; + +static struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} + +static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d) +{ + return container_of(d, struct sun6i_dma_dev, slave); +} + +static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan) +{ + return container_of(chan, struct sun6i_vchan, vc.chan); +} + +static inline struct sun6i_desc * +to_sun6i_desc(struct dma_async_tx_descriptor *tx) +{ + return container_of(tx, struct sun6i_desc, vd.tx); +} + +static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev) +{ + dev_dbg(sdev->slave.dev, "Common register:\n" + "\tmask0(%04x): 0x%08x\n" + "\tmask1(%04x): 0x%08x\n" + "\tpend0(%04x): 0x%08x\n" + "\tpend1(%04x): 0x%08x\n" + "\tstats(%04x): 0x%08x\n", + DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)), + DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)), + DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)), + DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)), + DMA_STAT, readl(sdev->base + DMA_STAT)); +} + +static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev, + struct sun6i_pchan *pchan) +{ + dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n" + "\t___en(%04x): \t0x%08x\n" + "\tpause(%04x): \t0x%08x\n" + "\tstart(%04x): \t0x%08x\n" + "\t__cfg(%04x): \t0x%08x\n" + "\t__src(%04x): \t0x%08x\n" + "\t__dst(%04x): \t0x%08x\n" + "\tcount(%04x): \t0x%08x\n" + "\t_para(%04x): \t0x%08x\n\n", + pchan->idx, __virt_to_phys((unsigned long)pchan->base), + DMA_CHAN_ENABLE, + readl(pchan->base + DMA_CHAN_ENABLE), + DMA_CHAN_PAUSE, + readl(pchan->base + DMA_CHAN_PAUSE), + DMA_CHAN_LLI_ADDR, + readl(pchan->base + DMA_CHAN_LLI_ADDR), + DMA_CHAN_CUR_CFG, + readl(pchan->base + DMA_CHAN_CUR_CFG), + DMA_CHAN_CUR_SRC, + readl(pchan->base + DMA_CHAN_CUR_SRC), + DMA_CHAN_CUR_DST, + readl(pchan->base + DMA_CHAN_CUR_DST), + DMA_CHAN_CUR_CNT, + readl(pchan->base + DMA_CHAN_CUR_CNT), + DMA_CHAN_CUR_PARA, + readl(pchan->base + DMA_CHAN_CUR_PARA)); +} + +static inline u8 convert_burst(u8 maxburst) +{ + if (maxburst == 1 || maxburst > 16) + return 0; + + return fls(maxburst) - 1; +} + +static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width) +{ + switch (addr_width) { + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return 1; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return 2; + default: + return 0; + } +} + +static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev, + struct sun6i_dma_lli *next, + dma_addr_t next_phy, + struct sun6i_desc *txd) +{ + if ((!prev && !txd) || !next) + return NULL; + + if (!prev) { + txd->p_lli = next_phy; + txd->v_lli = next; + } else { + prev->p_lli_next = next_phy; + prev->v_lli_next = next; + } + + next->p_lli_next = LLI_LAST_ITEM; + next->v_lli_next = NULL; + + return next; +} + +static inline void sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, + dma_addr_t src, + dma_addr_t dst, u32 len, + struct dma_slave_config *config) +{ + u32 src_width, dst_width, src_burst, dst_burst; + + if (!config) + return; + + src_burst = convert_burst(config->src_maxburst); + dst_burst = convert_burst(config->dst_maxburst); + + src_width = convert_buswidth(config->src_addr_width); + dst_width = convert_buswidth(config->dst_addr_width); + + lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) | + DMA_CHAN_CFG_SRC_WIDTH(src_width) | + DMA_CHAN_CFG_DST_BURST(dst_burst) | + DMA_CHAN_CFG_DST_WIDTH(dst_width); + + lli->src = src; + lli->dst = dst; + lli->len = len; + lli->para = NORMAL_WAIT; + +} + +static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan, + struct sun6i_dma_lli *lli) +{ + dev_dbg(chan2dev(&vchan->vc.chan), + "\n\tdesc: p - %pa v - 0x%08x\n" + "\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n" + "\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n", + __virt_to_phys((unsigned long)lli), (u32)lli, + lli->cfg, lli->src, lli->dst, + lli->len, lli->para, lli->p_lli_next); +} + +static void sun6i_dma_free_desc(struct virt_dma_desc *vd) +{ + struct sun6i_desc *txd = to_sun6i_desc(&vd->tx); + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device); + struct sun6i_dma_lli *v_lli, *v_next; + dma_addr_t p_lli, p_next; + + if (unlikely(!txd)) + return; + + p_lli = txd->p_lli; + v_lli = txd->v_lli; + + while (v_lli) { + v_next = v_lli->v_lli_next; + p_next = v_lli->p_lli_next; + + dma_pool_free(sdev->pool, v_lli, p_lli); + + v_lli = v_next; + p_lli = p_next; + } + + kfree(txd); +} + +static int sun6i_dma_terminate_all(struct sun6i_vchan *vchan) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); + struct sun6i_pchan *pchan = vchan->phy; + unsigned long flags; + LIST_HEAD(head); + + spin_lock(&sdev->lock); + list_del_init(&vchan->node); + spin_unlock(&sdev->lock); + + spin_lock_irqsave(&vchan->vc.lock, flags); + + vchan_get_all_descriptors(&vchan->vc, &head); + + if (pchan) { + writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE); + writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE); + + vchan->phy = NULL; + pchan->vchan = NULL; + pchan->desc = NULL; + pchan->done = NULL; + } + + spin_unlock_irqrestore(&vchan->vc.lock, flags); + + vchan_dma_desc_free_list(&vchan->vc, &head); + + return 0; +} + +static int sun6i_dma_start_desc(struct sun6i_vchan *vchan) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device); + struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc); + struct sun6i_pchan *pchan = vchan->phy; + u32 irq_val, irq_reg, irq_offset; + + if (!pchan) + return -EAGAIN; + + if (!desc) { + pchan->desc = NULL; + pchan->done = NULL; + return -EAGAIN; + } + + list_del(&desc->node); + + pchan->desc = to_sun6i_desc(&desc->tx); + pchan->done = NULL; + + sun6i_dma_dump_lli(vchan, pchan->desc->v_lli); + + irq_reg = pchan->idx / DMA_IRQ_CHAN_NR; + irq_offset = pchan->idx % DMA_IRQ_CHAN_NR; + + irq_val = readl(sdev->base + DMA_IRQ_EN(irq_offset)); + irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH); + writel(irq_val, sdev->base + DMA_IRQ_EN(irq_offset)); + + writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR); + writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE); + + sun6i_dma_dump_com_regs(sdev); + sun6i_dma_dump_chan_regs(sdev, pchan); + + return 0; +} + +static void sun6i_dma_tasklet(unsigned long data) +{ + struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data; + struct sun6i_vchan *vchan; + struct sun6i_pchan *pchan; + unsigned int pchan_alloc = 0; + unsigned int pchan_idx; + + list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) { + spin_lock_irq(&vchan->vc.lock); + + pchan = vchan->phy; + + if (pchan && pchan->done) { + if (sun6i_dma_start_desc(vchan)) { + /* + * No current txd associated with this channel + */ + dev_dbg(sdev->slave.dev, "pchan %u: free\n", + pchan->idx); + + /* Mark this channel free */ + vchan->phy = NULL; + pchan->vchan = NULL; + } + } + spin_unlock_irq(&vchan->vc.lock); + } + + spin_lock_irq(&sdev->lock); + for (pchan_idx = 0; pchan_idx < NR_MAX_CHANNELS; pchan_idx++) { + pchan = &sdev->pchans[pchan_idx]; + + if (pchan->vchan == NULL && !list_empty(&sdev->pending)) { + vchan = list_first_entry(&sdev->pending, + struct sun6i_vchan, node); + + /* Remove from pending channels */ + list_del_init(&vchan->node); + pchan_alloc |= BIT(pchan_idx); + + /* Mark this channel allocated */ + pchan->vchan = vchan; + vchan->phy = pchan; + dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n", + pchan->idx, &vchan->vc); + } + } + spin_unlock_irq(&sdev->lock); + + for (pchan_idx = 0; pchan_idx < NR_MAX_CHANNELS; pchan_idx++) { + if (pchan_alloc & BIT(pchan_idx)) { + pchan = sdev->pchans + pchan_idx; + vchan = pchan->vchan; + if (vchan) { + spin_lock_irq(&vchan->vc.lock); + sun6i_dma_start_desc(vchan); + spin_unlock_irq(&vchan->vc.lock); + } + } + } +} + +static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id) +{ + struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)dev_id; + struct sun6i_vchan *vchan; + struct sun6i_pchan *pchan; + int i, j, ret = IRQ_NONE; + u32 status; + + for (i = 0; i < 2; i++) { + status = readl(sdev->base + DMA_IRQ_STAT(i)); + if (!status) + continue; + + dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n", + i ? "high" : "low", status); + + writel(status, sdev->base + DMA_IRQ_STAT(i)); + + for (j = 0; (j < 8) && status; j++) { + if (status & DMA_IRQ_QUEUE) { + pchan = sdev->pchans + j; + vchan = pchan->vchan; + + if (vchan) { + unsigned long flags; + + spin_lock_irqsave(&vchan->vc.lock, + flags); + vchan_cookie_complete(&pchan->desc->vd); + pchan->done = pchan->desc; + spin_unlock_irqrestore(&vchan->vc.lock, + flags); + } + } + + status = status >> 4; + } + + tasklet_schedule(&sdev->task); + ret = IRQ_HANDLED; + } + + return ret; +} + +static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy( + struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, + size_t len, unsigned long flags) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + struct dma_slave_config *sconfig = &vchan->cfg; + struct sun6i_dma_lli *v_lli; + struct sun6i_desc *txd; + dma_addr_t p_lli; + + dev_dbg(chan2dev(chan), + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", + __func__, vchan->vc.chan.chan_id, dest, src, len, flags); + + if (!len) + return NULL; + + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); + if (!txd) + return NULL; + + v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); + if (!v_lli) { + dev_err(sdev->slave.dev, "Failed to alloc lli memory\n"); + kfree(txd); + return NULL; + } + + sun6i_dma_cfg_lli(v_lli, src, dest, len, sconfig); + v_lli->cfg |= DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | + DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | + DMA_CHAN_CFG_DST_LINEAR_MODE | + DMA_CHAN_CFG_SRC_LINEAR_MODE; + + sun6i_dma_lli_add(NULL, v_lli, p_lli, txd); + + sun6i_dma_dump_lli(vchan, v_lli); + + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); +} + +static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg( + struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, enum dma_transfer_direction dir, + unsigned long flags, void *context) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + struct dma_slave_config *sconfig = &vchan->cfg; + struct sun6i_dma_lli *v_lli, *prev = NULL; + struct sun6i_desc *txd; + struct scatterlist *sg; + dma_addr_t p_lli; + int i; + + if (!sgl) + return NULL; + + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); + if (!txd) + return NULL; + + for_each_sg(sgl, sg, sg_len, i) { + v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli); + if (!v_lli) { + kfree(txd); + return NULL; + } + + if (dir == DMA_MEM_TO_DEV) { + sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg), + sconfig->dst_addr, sg_dma_len(sg), + sconfig); + v_lli->cfg |= DMA_CHAN_CFG_DST_IO_MODE | + DMA_CHAN_CFG_SRC_LINEAR_MODE | + DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) | + DMA_CHAN_CFG_DST_DRQ(vchan->port); + + dev_dbg(chan2dev(chan), + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", + __func__, vchan->vc.chan.chan_id, + sconfig->dst_addr, sg_dma_address(sg), + sg_dma_len(sg), flags); + + } else if (dir == DMA_DEV_TO_MEM) { + sun6i_dma_cfg_lli(v_lli, sconfig->src_addr, + sg_dma_address(sg), sg_dma_len(sg), + sconfig); + v_lli->cfg |= DMA_CHAN_CFG_DST_LINEAR_MODE | + DMA_CHAN_CFG_SRC_IO_MODE | + DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) | + DMA_CHAN_CFG_SRC_DRQ(vchan->port); + + dev_dbg(chan2dev(chan), + "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n", + __func__, vchan->vc.chan.chan_id, + sg_dma_address(sg), sconfig->src_addr, + sg_dma_len(sg), flags); + } + + prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd); + } + +#ifdef DEBUG + dev_dbg(chan2dev(chan), "First: %pad\n", txd->p_lli); + for (prev = txd->v_lli; prev != NULL; prev = prev->v_lli_next) + sun6i_dma_dump_lli(vchan, prev); +#endif + + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); +} + +static int sun6i_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + struct sun6i_pchan *pchan = vchan->phy; + unsigned long flags; + int ret = 0; + + switch (cmd) { + case DMA_RESUME: + dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc); + + spin_lock_irqsave(&vchan->vc.lock, flags); + + if (pchan) { + writel(DMA_CHAN_PAUSE_RESUME, + pchan->base + DMA_CHAN_PAUSE); + } else if (!list_empty(&vchan->vc.desc_issued)) { + spin_lock(&sdev->lock); + list_add_tail(&vchan->node, &sdev->pending); + spin_unlock(&sdev->lock); + } + + spin_unlock_irqrestore(&vchan->vc.lock, flags); + break; + + case DMA_PAUSE: + dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc); + + if (pchan) { + writel(DMA_CHAN_PAUSE_PAUSE, + pchan->base + DMA_CHAN_PAUSE); + } else { + spin_lock(&sdev->lock); + list_del_init(&vchan->node); + spin_unlock(&sdev->lock); + } + break; + + case DMA_TERMINATE_ALL: + ret = sun6i_dma_terminate_all(vchan); + break; + case DMA_SLAVE_CONFIG: + memcpy(&vchan->cfg, (struct dma_slave_config *)arg, + sizeof(struct dma_slave_config)); + break; + default: + ret = -ENXIO; + break; + } + return ret; +} + +static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + struct sun6i_pchan *pchan = vchan->phy; + struct sun6i_dma_lli *lli; + struct virt_dma_desc *vd; + struct sun6i_desc *txd; + enum dma_status ret; + unsigned long flags; + size_t bytes = 0; + + ret = dma_cookie_status(chan, cookie, state); + if (ret == DMA_COMPLETE) + return ret; + + spin_lock_irqsave(&vchan->vc.lock, flags); + + vd = vchan_find_desc(&vchan->vc, cookie); + txd = to_sun6i_desc(&vd->tx); + + if (vd) { + for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next) + bytes += lli->len; + } else if (!pchan || !pchan->desc) { + bytes = 0; + } else { + bytes = readl(pchan->base + DMA_CHAN_CUR_CNT); + } + + spin_unlock_irqrestore(&vchan->vc.lock, flags); + + dma_set_residue(state, bytes); + + return ret; +} + +static void sun6i_dma_issue_pending(struct dma_chan *chan) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + unsigned long flags; + + spin_lock_irqsave(&vchan->vc.lock, flags); + + if (vchan_issue_pending(&vchan->vc)) { + spin_lock(&sdev->lock); + + if (!vchan->phy) { + if (list_empty(&vchan->node)) { + list_add_tail(&vchan->node, &sdev->pending); + tasklet_schedule(&sdev->task); + dev_dbg(chan2dev(chan), "vchan %p: issued\n", + &vchan->vc); + } + } + + spin_unlock(&sdev->lock); + } else { + dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n", + &vchan->vc); + } + + spin_unlock_irqrestore(&vchan->vc.lock, flags); +} + +static int sun6i_dma_alloc_chan_resources(struct dma_chan *chan) +{ + return 0; +} + +static void sun6i_dma_free_chan_resources(struct dma_chan *chan) +{ + struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device); + struct sun6i_vchan *vchan = to_sun6i_vchan(chan); + unsigned long flags; + + spin_lock_irqsave(&sdev->lock, flags); + list_del_init(&vchan->node); + spin_unlock_irqrestore(&sdev->lock, flags); + + vchan_free_chan_resources(&vchan->vc); +} + +static inline void sun6i_dma_free(struct sun6i_dma_dev *sdc) +{ + int i; + + for (i = 0; i < NR_MAX_VCHANS; i++) { + struct sun6i_vchan *vchan = &sdc->vchans[i]; + + list_del(&vchan->vc.chan.device_node); + tasklet_kill(&vchan->vc.task); + } + + tasklet_kill(&sdc->task); +} + +static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct sun6i_dma_dev *sdev = ofdma->of_dma_data; + struct sun6i_vchan *vchan; + struct dma_chan *chan; + u8 port = dma_spec->args[0]; + + if (port > NR_MAX_REQUESTS) + return NULL; + + chan = dma_get_any_slave_channel(&sdev->slave); + if (!chan) + return NULL; + + vchan = to_sun6i_vchan(chan); + vchan->port = port; + + return chan; +} + +static int sun6i_dma_probe(struct platform_device *pdev) +{ + struct sun6i_dma_dev *sdc; + struct resource *res; + struct clk *mux, *pll6; + int irq; + int ret, i; + + sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL); + if (!sdc) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sdc->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(sdc->base)) + return PTR_ERR(sdc->base); + + irq = platform_get_irq(pdev, 0); + ret = devm_request_irq(&pdev->dev, irq, sun6i_dma_interrupt, 0, + dev_name(&pdev->dev), sdc); + if (ret) { + dev_err(&pdev->dev, "Cannot request IRQ\n"); + return ret; + } + + sdc->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sdc->clk)) { + dev_err(&pdev->dev, "No clock specified\n"); + return PTR_ERR(sdc->clk); + } + + mux = devm_clk_get(&pdev->dev, "ahb1_mux"); + if (IS_ERR(mux)) { + pr_err("Couldn't get AHB1 Mux\n"); + return PTR_ERR(mux); + } + + pll6 = devm_clk_get(&pdev->dev, "pll6"); + if (IS_ERR(pll6)) { + pr_err("Couldn't get PLL6\n"); + return PTR_ERR(pll6); + } + + ret = clk_set_parent(mux, pll6); + if (ret) { + dev_err(&pdev->dev, "Couldn't reparent AHB1 on PLL6\n"); + return ret; + } + + devm_clk_put(&pdev->dev, mux); + devm_clk_put(&pdev->dev, pll6); + + sdc->rstc = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(sdc->rstc)) { + dev_err(&pdev->dev, "No reset controller specified\n"); + return PTR_ERR(sdc->rstc); + } + + sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev, + sizeof(struct sun6i_dma_lli), 4, 0); + if (!sdc->pool) { + dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, sdc); + INIT_LIST_HEAD(&sdc->pending); + spin_lock_init(&sdc->lock); + + dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask); + dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask); + dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask); + + INIT_LIST_HEAD(&sdc->slave.channels); + sdc->slave.device_alloc_chan_resources = sun6i_dma_alloc_chan_resources; + sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources; + sdc->slave.device_tx_status = sun6i_dma_tx_status; + sdc->slave.device_issue_pending = sun6i_dma_issue_pending; + sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg; + sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy; + sdc->slave.device_control = sun6i_dma_control; + sdc->slave.chancnt = NR_MAX_VCHANS; + + sdc->slave.dev = &pdev->dev; + + sdc->pchans = devm_kcalloc(&pdev->dev, NR_MAX_CHANNELS, + sizeof(struct sun6i_pchan), GFP_KERNEL); + if (!sdc->pchans) + return -ENOMEM; + + sdc->vchans = devm_kcalloc(&pdev->dev, NR_MAX_VCHANS, + sizeof(struct sun6i_vchan), GFP_KERNEL); + if (!sdc->vchans) + return -ENOMEM; + + tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc); + + for (i = 0; i < NR_MAX_CHANNELS; i++) { + struct sun6i_pchan *pchan = &sdc->pchans[i]; + + pchan->idx = i; + pchan->base = sdc->base + 0x100 + i * 0x40; + } + + for (i = 0; i < NR_MAX_VCHANS; i++) { + struct sun6i_vchan *vchan = &sdc->vchans[i]; + + INIT_LIST_HEAD(&vchan->node); + vchan->vc.desc_free = sun6i_dma_free_desc; + vchan_init(&vchan->vc, &sdc->slave); + } + + ret = reset_control_deassert(sdc->rstc); + if (ret) { + dev_err(&pdev->dev, "Couldn't deassert the device from reset\n"); + goto err_chan_free; + } + + ret = clk_prepare_enable(sdc->clk); + if (ret) { + dev_err(&pdev->dev, "Couldn't enable the clock\n"); + goto err_reset_assert; + } + + ret = dma_async_device_register(&sdc->slave); + if (ret) { + dev_warn(&pdev->dev, "Failed to register DMA engine device\n"); + goto err_clk_disable; + } + + ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate, + sdc); + if (ret) { + dev_err(&pdev->dev, "of_dma_controller_register failed\n"); + goto err_dma_unregister; + } + + return 0; + +err_dma_unregister: + dma_async_device_unregister(&sdc->slave); +err_clk_disable: + clk_disable_unprepare(sdc->clk); +err_reset_assert: + reset_control_assert(sdc->rstc); +err_chan_free: + sun6i_dma_free(sdc); + return ret; +} + +static int sun6i_dma_remove(struct platform_device *pdev) +{ + struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev); + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&sdc->slave); + + clk_disable_unprepare(sdc->clk); + reset_control_assert(sdc->rstc); + + sun6i_dma_free(sdc); + + return 0; +} + +static struct of_device_id sun6i_dma_match[] = { + { .compatible = "allwinner,sun6i-a31-dma" } +}; + +static struct platform_driver sun6i_dma_driver = { + .probe = sun6i_dma_probe, + .remove = sun6i_dma_remove, + .driver = { + .name = "sun6i-dma", + .of_match_table = sun6i_dma_match, + }, +}; +module_platform_driver(sun6i_dma_driver); + +MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver"); +MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_LICENSE("GPL");
The Allwinner A31 has a 16 channels DMA controller that it shares with the newer A23. Although sharing some similarities with the DMA controller of the older Allwinner SoCs, it's significantly different, I don't expect it to be possible to share the driver for these two. The A31 Controller is able to memory-to-memory or memory-to-device transfers on the 16 channels in parallel. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> --- .../devicetree/bindings/dma/sun6i-dma.txt | 45 + drivers/dma/Kconfig | 8 + drivers/dma/Makefile | 1 + drivers/dma/sun6i-dma.c | 979 +++++++++++++++++++++ 4 files changed, 1033 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/sun6i-dma.txt create mode 100644 drivers/dma/sun6i-dma.c