diff options
Diffstat (limited to 'drivers/dma/sun6i-dma.c')
| -rw-r--r-- | drivers/dma/sun6i-dma.c | 1053 |
1 files changed, 1053 insertions, 0 deletions
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c new file mode 100644 index 0000000..1f92a56 --- /dev/null +++ b/drivers/dma/sun6i-dma.c @@ -0,0 +1,1053 @@ +/* + * 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; + + /* + * This field is not used by the DMA controller, but will be + * used by the CPU to go through the list (mostly for dumping + * or freeing it). + */ + struct sun6i_dma_lli *v_lli_next; +}; + + +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; + int irq; + spinlock_t lock; + struct reset_control *rstc; + struct tasklet_struct task; + atomic_t tasklet_shutdown; + 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) +{ + phys_addr_t reg = virt_to_phys(pchan->base); + + 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, ®, + 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 int convert_burst(u32 maxburst, u8 *burst) +{ + switch (maxburst) { + case 1: + *burst = 0; + break; + case 8: + *burst = 2; + break; + default: + return -EINVAL; + } + + return 0; +} + +static inline int convert_buswidth(enum dma_slave_buswidth addr_width, u8 *width) +{ + if ((addr_width < DMA_SLAVE_BUSWIDTH_1_BYTE) || + (addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES)) + return -EINVAL; + + *width = addr_width >> 1; + 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 int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, + dma_addr_t src, + dma_addr_t dst, u32 len, + struct dma_slave_config *config) +{ + u8 src_width, dst_width, src_burst, dst_burst; + int ret; + + if (!config) + return -EINVAL; + + ret = convert_burst(config->src_maxburst, &src_burst); + if (ret) + return ret; + + ret = convert_burst(config->dst_maxburst, &dst_burst); + if (ret) + return ret; + + ret = convert_buswidth(config->src_addr_width, &src_width); + if (ret) + return ret; + + ret = convert_buswidth(config->dst_addr_width, &dst_width); + if (ret) + return ret; + + 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; + + return 0; +} + +static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan, + struct sun6i_dma_lli *lli) +{ + phys_addr_t p_lli = virt_to_phys(lli); + + dev_dbg(chan2dev(&vchan->vc.chan), + "\n\tdesc: p - %pa v - 0x%p\n" + "\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n" + "\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n", + &p_lli, 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 || list_empty(&sdev->pending)) + continue; + + 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))) + continue; + + 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 = 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) { + spin_lock(&vchan->vc.lock); + vchan_cookie_complete(&pchan->desc->vd); + pchan->done = pchan->desc; + spin_unlock(&vchan->vc.lock); + } + } + + status = status >> 4; + } + + if (!atomic_read(&sdev->tasklet_shutdown)) + 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; + int ret; + + 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"); + goto err_txd_free; + } + + ret = sun6i_dma_cfg_lli(v_lli, src, dest, len, sconfig); + if (ret) + goto err_dma_free; + + 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); + +err_dma_free: + dma_pool_free(sdev->pool, v_lli, p_lli); +err_txd_free: + kfree(txd); + return NULL; +} + +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, ret; + + if (!sgl) + return NULL; + + if (!is_slave_direction(dir)) { + dev_err(chan2dev(chan), "Invalid DMA direction\n"); + 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) + goto err_lli_free; + + if (dir == DMA_MEM_TO_DEV) { + ret = sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg), + sconfig->dst_addr, sg_dma_len(sg), + sconfig); + if (ret) + goto err_cur_lli_free; + + 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: %u. flags: 0x%08lx\n", + __func__, vchan->vc.chan.chan_id, + &sconfig->dst_addr, &sg_dma_address(sg), + sg_dma_len(sg), flags); + + } else { + ret = sun6i_dma_cfg_lli(v_lli, sconfig->src_addr, + sg_dma_address(sg), sg_dma_len(sg), + sconfig); + if (ret) + goto err_cur_lli_free; + + 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: %u. 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); + } + + dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli); + for (prev = txd->v_lli; prev; prev = prev->v_lli_next) + sun6i_dma_dump_lli(vchan, prev); + + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); + +err_cur_lli_free: + dma_pool_free(sdev->pool, v_lli, p_lli); +err_lli_free: + for (prev = txd->v_lli; prev; prev = prev->v_lli_next) + dma_pool_free(sdev->pool, prev, virt_to_phys(prev)); + kfree(txd); + return NULL; +} + +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, (void *)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 && 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 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 inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev) +{ + /* Disable all interrupts from DMA */ + writel(0, sdev->base + DMA_IRQ_EN(0)); + writel(0, sdev->base + DMA_IRQ_EN(1)); + + /* Prevent spurious interrupts from scheduling the tasklet */ + atomic_inc(&sdev->tasklet_shutdown); + + /* Make sure we won't have any further interrupts */ + devm_free_irq(sdev->slave.dev, sdev->irq, sdev); + + /* Actually prevent the tasklet from being scheduled */ + tasklet_kill(&sdev->task); +} + +static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev) +{ + int i; + + for (i = 0; i < NR_MAX_VCHANS; i++) { + struct sun6i_vchan *vchan = &sdev->vchans[i]; + + list_del(&vchan->vc.chan.device_node); + tasklet_kill(&vchan->vc.task); + } +} + +static int sun6i_dma_probe(struct platform_device *pdev) +{ + struct sun6i_dma_dev *sdc; + struct resource *res; + struct clk *mux, *pll6; + 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); + + sdc->irq = platform_get_irq(pdev, 0); + if (sdc->irq < 0) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + return sdc->irq; + } + + 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 = clk_get(NULL, "ahb1_mux"); + if (IS_ERR(mux)) { + dev_err(&pdev->dev, "Couldn't get AHB1 Mux\n"); + return PTR_ERR(mux); + } + + pll6 = clk_get(NULL, "pll6"); + if (IS_ERR(pll6)) { + dev_err(&pdev->dev, "Couldn't get PLL6\n"); + clk_put(mux); + return PTR_ERR(pll6); + } + + ret = clk_set_parent(mux, pll6); + clk_put(pll6); + clk_put(mux); + + if (ret) { + dev_err(&pdev->dev, "Couldn't reparent AHB1 on PLL6\n"); + return ret; + } + + 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 = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0, + dev_name(&pdev->dev), sdc); + if (ret) { + dev_err(&pdev->dev, "Cannot request IRQ\n"); + goto err_clk_disable; + } + + ret = dma_async_device_register(&sdc->slave); + if (ret) { + dev_warn(&pdev->dev, "Failed to register DMA engine device\n"); + goto err_irq_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_irq_disable: + sun6i_kill_tasklet(sdc); +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); + + sun6i_kill_tasklet(sdc); + + 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" }, + { /* sentinel */ } +}; + +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"); |
