diff options
Diffstat (limited to 'drivers/dma/zx_dma.c')
| -rw-r--r-- | drivers/dma/zx_dma.c | 952 |
1 files changed, 952 insertions, 0 deletions
diff --git a/drivers/dma/zx_dma.c b/drivers/dma/zx_dma.c new file mode 100644 index 000000000000..2bb695315300 --- /dev/null +++ b/drivers/dma/zx_dma.c @@ -0,0 +1,952 @@ +/* + * Copyright 2015 Linaro. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/sched.h> +#include <linux/device.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/clk.h> +#include <linux/of_dma.h> + +#include "virt-dma.h" + +#define DRIVER_NAME "zx-dma" +#define DMA_ALIGN 4 +#define DMA_MAX_SIZE (0x10000 - 512) +#define LLI_BLOCK_SIZE (4 * PAGE_SIZE) + +#define REG_ZX_SRC_ADDR 0x00 +#define REG_ZX_DST_ADDR 0x04 +#define REG_ZX_TX_X_COUNT 0x08 +#define REG_ZX_TX_ZY_COUNT 0x0c +#define REG_ZX_SRC_ZY_STEP 0x10 +#define REG_ZX_DST_ZY_STEP 0x14 +#define REG_ZX_LLI_ADDR 0x1c +#define REG_ZX_CTRL 0x20 +#define REG_ZX_TC_IRQ 0x800 +#define REG_ZX_SRC_ERR_IRQ 0x804 +#define REG_ZX_DST_ERR_IRQ 0x808 +#define REG_ZX_CFG_ERR_IRQ 0x80c +#define REG_ZX_TC_IRQ_RAW 0x810 +#define REG_ZX_SRC_ERR_IRQ_RAW 0x814 +#define REG_ZX_DST_ERR_IRQ_RAW 0x818 +#define REG_ZX_CFG_ERR_IRQ_RAW 0x81c +#define REG_ZX_STATUS 0x820 +#define REG_ZX_DMA_GRP_PRIO 0x824 +#define REG_ZX_DMA_ARB 0x828 + +#define ZX_FORCE_CLOSE BIT(31) +#define ZX_DST_BURST_WIDTH(x) (((x) & 0x7) << 13) +#define ZX_MAX_BURST_LEN 16 +#define ZX_SRC_BURST_LEN(x) (((x) & 0xf) << 9) +#define ZX_SRC_BURST_WIDTH(x) (((x) & 0x7) << 6) +#define ZX_IRQ_ENABLE_ALL (3 << 4) +#define ZX_DST_FIFO_MODE BIT(3) +#define ZX_SRC_FIFO_MODE BIT(2) +#define ZX_SOFT_REQ BIT(1) +#define ZX_CH_ENABLE BIT(0) + +#define ZX_DMA_BUSWIDTHS \ + (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \ + BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)) + +enum zx_dma_burst_width { + ZX_DMA_WIDTH_8BIT = 0, + ZX_DMA_WIDTH_16BIT = 1, + ZX_DMA_WIDTH_32BIT = 2, + ZX_DMA_WIDTH_64BIT = 3, +}; + +struct zx_desc_hw { + u32 saddr; + u32 daddr; + u32 src_x; + u32 src_zy; + u32 src_zy_step; + u32 dst_zy_step; + u32 reserved1; + u32 lli; + u32 ctr; + u32 reserved[7]; /* pack as hardware registers region size */ +} __aligned(32); + +struct zx_dma_desc_sw { + struct virt_dma_desc vd; + dma_addr_t desc_hw_lli; + size_t desc_num; + size_t size; + struct zx_desc_hw *desc_hw; +}; + +struct zx_dma_phy; + +struct zx_dma_chan { + struct dma_slave_config slave_cfg; + int id; /* Request phy chan id */ + u32 ccfg; + u32 cyclic; + struct virt_dma_chan vc; + struct zx_dma_phy *phy; + struct list_head node; + dma_addr_t dev_addr; + enum dma_status status; +}; + +struct zx_dma_phy { + u32 idx; + void __iomem *base; + struct zx_dma_chan *vchan; + struct zx_dma_desc_sw *ds_run; + struct zx_dma_desc_sw *ds_done; +}; + +struct zx_dma_dev { + struct dma_device slave; + void __iomem *base; + spinlock_t lock; /* lock for ch and phy */ + struct list_head chan_pending; + struct zx_dma_phy *phy; + struct zx_dma_chan *chans; + struct clk *clk; + struct dma_pool *pool; + u32 dma_channels; + u32 dma_requests; + int irq; +}; + +#define to_zx_dma(dmadev) container_of(dmadev, struct zx_dma_dev, slave) + +static struct zx_dma_chan *to_zx_chan(struct dma_chan *chan) +{ + return container_of(chan, struct zx_dma_chan, vc.chan); +} + +static void zx_dma_terminate_chan(struct zx_dma_phy *phy, struct zx_dma_dev *d) +{ + u32 val = 0; + + val = readl_relaxed(phy->base + REG_ZX_CTRL); + val &= ~ZX_CH_ENABLE; + val |= ZX_FORCE_CLOSE; + writel_relaxed(val, phy->base + REG_ZX_CTRL); + + val = 0x1 << phy->idx; + writel_relaxed(val, d->base + REG_ZX_TC_IRQ_RAW); + writel_relaxed(val, d->base + REG_ZX_SRC_ERR_IRQ_RAW); + writel_relaxed(val, d->base + REG_ZX_DST_ERR_IRQ_RAW); + writel_relaxed(val, d->base + REG_ZX_CFG_ERR_IRQ_RAW); +} + +static void zx_dma_set_desc(struct zx_dma_phy *phy, struct zx_desc_hw *hw) +{ + writel_relaxed(hw->saddr, phy->base + REG_ZX_SRC_ADDR); + writel_relaxed(hw->daddr, phy->base + REG_ZX_DST_ADDR); + writel_relaxed(hw->src_x, phy->base + REG_ZX_TX_X_COUNT); + writel_relaxed(0, phy->base + REG_ZX_TX_ZY_COUNT); + writel_relaxed(0, phy->base + REG_ZX_SRC_ZY_STEP); + writel_relaxed(0, phy->base + REG_ZX_DST_ZY_STEP); + writel_relaxed(hw->lli, phy->base + REG_ZX_LLI_ADDR); + writel_relaxed(hw->ctr, phy->base + REG_ZX_CTRL); +} + +static u32 zx_dma_get_curr_lli(struct zx_dma_phy *phy) +{ + return readl_relaxed(phy->base + REG_ZX_LLI_ADDR); +} + +static u32 zx_dma_get_chan_stat(struct zx_dma_dev *d) +{ + return readl_relaxed(d->base + REG_ZX_STATUS); +} + +static void zx_dma_init_state(struct zx_dma_dev *d) +{ + /* set same priority */ + writel_relaxed(0x0, d->base + REG_ZX_DMA_ARB); + /* clear all irq */ + writel_relaxed(0xffffffff, d->base + REG_ZX_TC_IRQ_RAW); + writel_relaxed(0xffffffff, d->base + REG_ZX_SRC_ERR_IRQ_RAW); + writel_relaxed(0xffffffff, d->base + REG_ZX_DST_ERR_IRQ_RAW); + writel_relaxed(0xffffffff, d->base + REG_ZX_CFG_ERR_IRQ_RAW); +} + +static int zx_dma_start_txd(struct zx_dma_chan *c) +{ + struct zx_dma_dev *d = to_zx_dma(c->vc.chan.device); + struct virt_dma_desc *vd = vchan_next_desc(&c->vc); + + if (!c->phy) + return -EAGAIN; + + if (BIT(c->phy->idx) & zx_dma_get_chan_stat(d)) + return -EAGAIN; + + if (vd) { + struct zx_dma_desc_sw *ds = + container_of(vd, struct zx_dma_desc_sw, vd); + /* + * fetch and remove request from vc->desc_issued + * so vc->desc_issued only contains desc pending + */ + list_del(&ds->vd.node); + c->phy->ds_run = ds; + c->phy->ds_done = NULL; + /* start dma */ + zx_dma_set_desc(c->phy, ds->desc_hw); + return 0; + } + c->phy->ds_done = NULL; + c->phy->ds_run = NULL; + return -EAGAIN; +} + +static void zx_dma_task(struct zx_dma_dev *d) +{ + struct zx_dma_phy *p; + struct zx_dma_chan *c, *cn; + unsigned pch, pch_alloc = 0; + unsigned long flags; + + /* check new dma request of running channel in vc->desc_issued */ + list_for_each_entry_safe(c, cn, &d->slave.channels, + vc.chan.device_node) { + spin_lock_irqsave(&c->vc.lock, flags); + p = c->phy; + if (p && p->ds_done && zx_dma_start_txd(c)) { + /* No current txd associated with this channel */ + dev_dbg(d->slave.dev, "pchan %u: free\n", p->idx); + /* Mark this channel free */ + c->phy = NULL; + p->vchan = NULL; + } + spin_unlock_irqrestore(&c->vc.lock, flags); + } + + /* check new channel request in d->chan_pending */ + spin_lock_irqsave(&d->lock, flags); + while (!list_empty(&d->chan_pending)) { + c = list_first_entry(&d->chan_pending, + struct zx_dma_chan, node); + p = &d->phy[c->id]; + if (!p->vchan) { + /* remove from d->chan_pending */ + list_del_init(&c->node); + pch_alloc |= 1 << c->id; + /* Mark this channel allocated */ + p->vchan = c; + c->phy = p; + } else { + dev_dbg(d->slave.dev, "pchan %u: busy!\n", c->id); + } + } + spin_unlock_irqrestore(&d->lock, flags); + + for (pch = 0; pch < d->dma_channels; pch++) { + if (pch_alloc & (1 << pch)) { + p = &d->phy[pch]; + c = p->vchan; + if (c) { + spin_lock_irqsave(&c->vc.lock, flags); + zx_dma_start_txd(c); + spin_unlock_irqrestore(&c->vc.lock, flags); + } + } + } +} + +static irqreturn_t zx_dma_int_handler(int irq, void *dev_id) +{ + struct zx_dma_dev *d = (struct zx_dma_dev *)dev_id; + struct zx_dma_phy *p; + struct zx_dma_chan *c; + u32 tc = readl_relaxed(d->base + REG_ZX_TC_IRQ); + u32 serr = readl_relaxed(d->base + REG_ZX_SRC_ERR_IRQ); + u32 derr = readl_relaxed(d->base + REG_ZX_DST_ERR_IRQ); + u32 cfg = readl_relaxed(d->base + REG_ZX_CFG_ERR_IRQ); + u32 i, irq_chan = 0, task = 0; + + while (tc) { + i = __ffs(tc); + tc &= ~BIT(i); + p = &d->phy[i]; + c = p->vchan; + if (c) { + unsigned long flags; + + spin_lock_irqsave(&c->vc.lock, flags); + if (c->cyclic) { + vchan_cyclic_callback(&p->ds_run->vd); + } else { + vchan_cookie_complete(&p->ds_run->vd); + p->ds_done = p->ds_run; + task = 1; + } + spin_unlock_irqrestore(&c->vc.lock, flags); + irq_chan |= BIT(i); + } + } + + if (serr || derr || cfg) + dev_warn(d->slave.dev, "DMA ERR src 0x%x, dst 0x%x, cfg 0x%x\n", + serr, derr, cfg); + + writel_relaxed(irq_chan, d->base + REG_ZX_TC_IRQ_RAW); + writel_relaxed(serr, d->base + REG_ZX_SRC_ERR_IRQ_RAW); + writel_relaxed(derr, d->base + REG_ZX_DST_ERR_IRQ_RAW); + writel_relaxed(cfg, d->base + REG_ZX_CFG_ERR_IRQ_RAW); + + if (task) + zx_dma_task(d); + return IRQ_HANDLED; +} + +static void zx_dma_free_chan_resources(struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_dev *d = to_zx_dma(chan->device); + unsigned long flags; + + spin_lock_irqsave(&d->lock, flags); + list_del_init(&c->node); + spin_unlock_irqrestore(&d->lock, flags); + + vchan_free_chan_resources(&c->vc); + c->ccfg = 0; +} + +static enum dma_status zx_dma_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_phy *p; + struct virt_dma_desc *vd; + unsigned long flags; + enum dma_status ret; + size_t bytes = 0; + + ret = dma_cookie_status(&c->vc.chan, cookie, state); + if (ret == DMA_COMPLETE || !state) + return ret; + + spin_lock_irqsave(&c->vc.lock, flags); + p = c->phy; + ret = c->status; + + /* + * If the cookie is on our issue queue, then the residue is + * its total size. + */ + vd = vchan_find_desc(&c->vc, cookie); + if (vd) { + bytes = container_of(vd, struct zx_dma_desc_sw, vd)->size; + } else if ((!p) || (!p->ds_run)) { + bytes = 0; + } else { + struct zx_dma_desc_sw *ds = p->ds_run; + u32 clli = 0, index = 0; + + bytes = 0; + clli = zx_dma_get_curr_lli(p); + index = (clli - ds->desc_hw_lli) / + sizeof(struct zx_desc_hw) + 1; + for (; index < ds->desc_num; index++) { + bytes += ds->desc_hw[index].src_x; + /* end of lli */ + if (!ds->desc_hw[index].lli) + break; + } + } + spin_unlock_irqrestore(&c->vc.lock, flags); + dma_set_residue(state, bytes); + return ret; +} + +static void zx_dma_issue_pending(struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_dev *d = to_zx_dma(chan->device); + unsigned long flags; + int issue = 0; + + spin_lock_irqsave(&c->vc.lock, flags); + /* add request to vc->desc_issued */ + if (vchan_issue_pending(&c->vc)) { + spin_lock(&d->lock); + if (!c->phy && list_empty(&c->node)) { + /* if new channel, add chan_pending */ + list_add_tail(&c->node, &d->chan_pending); + issue = 1; + dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc); + } + spin_unlock(&d->lock); + } else { + dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc); + } + spin_unlock_irqrestore(&c->vc.lock, flags); + + if (issue) + zx_dma_task(d); +} + +static void zx_dma_fill_desc(struct zx_dma_desc_sw *ds, dma_addr_t dst, + dma_addr_t src, size_t len, u32 num, u32 ccfg) +{ + if ((num + 1) < ds->desc_num) + ds->desc_hw[num].lli = ds->desc_hw_lli + (num + 1) * + sizeof(struct zx_desc_hw); + ds->desc_hw[num].saddr = src; + ds->desc_hw[num].daddr = dst; + ds->desc_hw[num].src_x = len; + ds->desc_hw[num].ctr = ccfg; +} + +static struct zx_dma_desc_sw *zx_alloc_desc_resource(int num, + struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_desc_sw *ds; + struct zx_dma_dev *d = to_zx_dma(chan->device); + int lli_limit = LLI_BLOCK_SIZE / sizeof(struct zx_desc_hw); + + if (num > lli_limit) { + dev_dbg(chan->device->dev, "vch %p: sg num %d exceed max %d\n", + &c->vc, num, lli_limit); + return NULL; + } + + ds = kzalloc(sizeof(*ds), GFP_ATOMIC); + if (!ds) + return NULL; + + ds->desc_hw = dma_pool_zalloc(d->pool, GFP_NOWAIT, &ds->desc_hw_lli); + if (!ds->desc_hw) { + dev_dbg(chan->device->dev, "vch %p: dma alloc fail\n", &c->vc); + kfree(ds); + return NULL; + } + ds->desc_num = num; + return ds; +} + +static enum zx_dma_burst_width zx_dma_burst_width(enum dma_slave_buswidth width) +{ + switch (width) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + case DMA_SLAVE_BUSWIDTH_2_BYTES: + case DMA_SLAVE_BUSWIDTH_4_BYTES: + case DMA_SLAVE_BUSWIDTH_8_BYTES: + return ffs(width) - 1; + default: + return ZX_DMA_WIDTH_32BIT; + } +} + +static int zx_pre_config(struct zx_dma_chan *c, enum dma_transfer_direction dir) +{ + struct dma_slave_config *cfg = &c->slave_cfg; + enum zx_dma_burst_width src_width; + enum zx_dma_burst_width dst_width; + u32 maxburst = 0; + + switch (dir) { + case DMA_MEM_TO_MEM: + c->ccfg = ZX_CH_ENABLE | ZX_SOFT_REQ + | ZX_SRC_BURST_LEN(ZX_MAX_BURST_LEN - 1) + | ZX_SRC_BURST_WIDTH(ZX_DMA_WIDTH_32BIT) + | ZX_DST_BURST_WIDTH(ZX_DMA_WIDTH_32BIT); + break; + case DMA_MEM_TO_DEV: + c->dev_addr = cfg->dst_addr; + /* dst len is calculated from src width, len and dst width. + * We need make sure dst len not exceed MAX LEN. + * Trailing single transaction that does not fill a full + * burst also require identical src/dst data width. + */ + dst_width = zx_dma_burst_width(cfg->dst_addr_width); + maxburst = cfg->dst_maxburst; + maxburst = maxburst < ZX_MAX_BURST_LEN ? + maxburst : ZX_MAX_BURST_LEN; + c->ccfg = ZX_DST_FIFO_MODE | ZX_CH_ENABLE + | ZX_SRC_BURST_LEN(maxburst - 1) + | ZX_SRC_BURST_WIDTH(dst_width) + | ZX_DST_BURST_WIDTH(dst_width); + break; + case DMA_DEV_TO_MEM: + c->dev_addr = cfg->src_addr; + src_width = zx_dma_burst_width(cfg->src_addr_width); + maxburst = cfg->src_maxburst; + maxburst = maxburst < ZX_MAX_BURST_LEN ? + maxburst : ZX_MAX_BURST_LEN; + c->ccfg = ZX_SRC_FIFO_MODE | ZX_CH_ENABLE + | ZX_SRC_BURST_LEN(maxburst - 1) + | ZX_SRC_BURST_WIDTH(src_width) + | ZX_DST_BURST_WIDTH(src_width); + break; + default: + return -EINVAL; + } + return 0; +} + +static struct dma_async_tx_descriptor *zx_dma_prep_memcpy( + struct dma_chan *chan, dma_addr_t dst, dma_addr_t src, + size_t len, unsigned long flags) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_desc_sw *ds; + size_t copy = 0; + int num = 0; + + if (!len) + return NULL; + + if (zx_pre_config(c, DMA_MEM_TO_MEM)) + return NULL; + + num = DIV_ROUND_UP(len, DMA_MAX_SIZE); + + ds = zx_alloc_desc_resource(num, chan); + if (!ds) + return NULL; + + ds->size = len; + num = 0; + + do { + copy = min_t(size_t, len, DMA_MAX_SIZE); + zx_dma_fill_desc(ds, dst, src, copy, num++, c->ccfg); + + src += copy; + dst += copy; + len -= copy; + } while (len); + + c->cyclic = 0; + ds->desc_hw[num - 1].lli = 0; /* end of link */ + ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL; + return vchan_tx_prep(&c->vc, &ds->vd, flags); +} + +static struct dma_async_tx_descriptor *zx_dma_prep_slave_sg( + struct dma_chan *chan, struct scatterlist *sgl, unsigned int sglen, + enum dma_transfer_direction dir, unsigned long flags, void *context) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_desc_sw *ds; + size_t len, avail, total = 0; + struct scatterlist *sg; + dma_addr_t addr, src = 0, dst = 0; + int num = sglen, i; + + if (!sgl) + return NULL; + + if (zx_pre_config(c, dir)) + return NULL; + + for_each_sg(sgl, sg, sglen, i) { + avail = sg_dma_len(sg); + if (avail > DMA_MAX_SIZE) + num += DIV_ROUND_UP(avail, DMA_MAX_SIZE) - 1; + } + + ds = zx_alloc_desc_resource(num, chan); + if (!ds) + return NULL; + + c->cyclic = 0; + num = 0; + for_each_sg(sgl, sg, sglen, i) { + addr = sg_dma_address(sg); + avail = sg_dma_len(sg); + total += avail; + + do { + len = min_t(size_t, avail, DMA_MAX_SIZE); + + if (dir == DMA_MEM_TO_DEV) { + src = addr; + dst = c->dev_addr; + } else if (dir == DMA_DEV_TO_MEM) { + src = c->dev_addr; + dst = addr; + } + + zx_dma_fill_desc(ds, dst, src, len, num++, c->ccfg); + + addr += len; + avail -= len; + } while (avail); + } + + ds->desc_hw[num - 1].lli = 0; /* end of link */ + ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL; + ds->size = total; + return vchan_tx_prep(&c->vc, &ds->vd, flags); +} + +static struct dma_async_tx_descriptor *zx_dma_prep_dma_cyclic( + struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction dir, + unsigned long flags) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_desc_sw *ds; + dma_addr_t src = 0, dst = 0; + int num_periods = buf_len / period_len; + int buf = 0, num = 0; + + if (period_len > DMA_MAX_SIZE) { + dev_err(chan->device->dev, "maximum period size exceeded\n"); + return NULL; + } + + if (zx_pre_config(c, dir)) + return NULL; + + ds = zx_alloc_desc_resource(num_periods, chan); + if (!ds) + return NULL; + c->cyclic = 1; + + while (buf < buf_len) { + if (dir == DMA_MEM_TO_DEV) { + src = dma_addr; + dst = c->dev_addr; + } else if (dir == DMA_DEV_TO_MEM) { + src = c->dev_addr; + dst = dma_addr; + } + zx_dma_fill_desc(ds, dst, src, period_len, num++, + c->ccfg | ZX_IRQ_ENABLE_ALL); + dma_addr += period_len; + buf += period_len; + } + + ds->desc_hw[num - 1].lli = ds->desc_hw_lli; + ds->size = buf_len; + return vchan_tx_prep(&c->vc, &ds->vd, flags); +} + +static int zx_dma_config(struct dma_chan *chan, + struct dma_slave_config *cfg) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + + if (!cfg) + return -EINVAL; + + memcpy(&c->slave_cfg, cfg, sizeof(*cfg)); + + return 0; +} + +static int zx_dma_terminate_all(struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + struct zx_dma_dev *d = to_zx_dma(chan->device); + struct zx_dma_phy *p = c->phy; + unsigned long flags; + LIST_HEAD(head); + + dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc); + + /* Prevent this channel being scheduled */ + spin_lock(&d->lock); + list_del_init(&c->node); + spin_unlock(&d->lock); + + /* Clear the tx descriptor lists */ + spin_lock_irqsave(&c->vc.lock, flags); + vchan_get_all_descriptors(&c->vc, &head); + if (p) { + /* vchan is assigned to a pchan - stop the channel */ + zx_dma_terminate_chan(p, d); + c->phy = NULL; + p->vchan = NULL; + p->ds_run = NULL; + p->ds_done = NULL; + } + spin_unlock_irqrestore(&c->vc.lock, flags); + vchan_dma_desc_free_list(&c->vc, &head); + + return 0; +} + +static int zx_dma_transfer_pause(struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + u32 val = 0; + + val = readl_relaxed(c->phy->base + REG_ZX_CTRL); + val &= ~ZX_CH_ENABLE; + writel_relaxed(val, c->phy->base + REG_ZX_CTRL); + + return 0; +} + +static int zx_dma_transfer_resume(struct dma_chan *chan) +{ + struct zx_dma_chan *c = to_zx_chan(chan); + u32 val = 0; + + val = readl_relaxed(c->phy->base + REG_ZX_CTRL); + val |= ZX_CH_ENABLE; + writel_relaxed(val, c->phy->base + REG_ZX_CTRL); + + return 0; +} + +static void zx_dma_free_desc(struct virt_dma_desc *vd) +{ + struct zx_dma_desc_sw *ds = + container_of(vd, struct zx_dma_desc_sw, vd); + struct zx_dma_dev *d = to_zx_dma(vd->tx.chan->device); + + dma_pool_free(d->pool, ds->desc_hw, ds->desc_hw_lli); + kfree(ds); +} + +static const struct of_device_id zx6702_dma_dt_ids[] = { + { .compatible = "zte,zx296702-dma", }, + {} +}; +MODULE_DEVICE_TABLE(of, zx6702_dma_dt_ids); + +static struct dma_chan *zx_of_dma_simple_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct zx_dma_dev *d = ofdma->of_dma_data; + unsigned int request = dma_spec->args[0]; + struct dma_chan *chan; + struct zx_dma_chan *c; + + if (request >= d->dma_requests) + return NULL; + + chan = dma_get_any_slave_channel(&d->slave); + if (!chan) { + dev_err(d->slave.dev, "get channel fail in %s.\n", __func__); + return NULL; + } + c = to_zx_chan(chan); + c->id = request; + dev_info(d->slave.dev, "zx_dma: pchan %u: alloc vchan %p\n", + c->id, &c->vc); + return chan; +} + +static int zx_dma_probe(struct platform_device *op) +{ + struct zx_dma_dev *d; + struct resource *iores; + int i, ret = 0; + + iores = platform_get_resource(op, IORESOURCE_MEM, 0); + if (!iores) + return -EINVAL; + + d = devm_kzalloc(&op->dev, sizeof(*d), GFP_KERNEL); + if (!d) + return -ENOMEM; + + d->base = devm_ioremap_resource(&op->dev, iores); + if (IS_ERR(d->base)) + return PTR_ERR(d->base); + + of_property_read_u32((&op->dev)->of_node, + "dma-channels", &d->dma_channels); + of_property_read_u32((&op->dev)->of_node, + "dma-requests", &d->dma_requests); + if (!d->dma_requests || !d->dma_channels) + return -EINVAL; + + d->clk = devm_clk_get(&op->dev, NULL); + if (IS_ERR(d->clk)) { + dev_err(&op->dev, "no dma clk\n"); + return PTR_ERR(d->clk); + } + + d->irq = platform_get_irq(op, 0); + ret = devm_request_irq(&op->dev, d->irq, zx_dma_int_handler, + 0, DRIVER_NAME, d); + if (ret) + return ret; + + /* A DMA memory pool for LLIs, align on 32-byte boundary */ + d->pool = dmam_pool_create(DRIVER_NAME, &op->dev, + LLI_BLOCK_SIZE, 32, 0); + if (!d->pool) + return -ENOMEM; + + /* init phy channel */ + d->phy = devm_kzalloc(&op->dev, + d->dma_channels * sizeof(struct zx_dma_phy), GFP_KERNEL); + if (!d->phy) + return -ENOMEM; + + for (i = 0; i < d->dma_channels; i++) { + struct zx_dma_phy *p = &d->phy[i]; + + p->idx = i; + p->base = d->base + i * 0x40; + } + + INIT_LIST_HEAD(&d->slave.channels); + dma_cap_set(DMA_SLAVE, d->slave.cap_mask); + dma_cap_set(DMA_MEMCPY, d->slave.cap_mask); + dma_cap_set(DMA_CYCLIC, d->slave.cap_mask); + dma_cap_set(DMA_PRIVATE, d->slave.cap_mask); + d->slave.dev = &op->dev; + d->slave.device_free_chan_resources = zx_dma_free_chan_resources; + d->slave.device_tx_status = zx_dma_tx_status; + d->slave.device_prep_dma_memcpy = zx_dma_prep_memcpy; + d->slave.device_prep_slave_sg = zx_dma_prep_slave_sg; + d->slave.device_prep_dma_cyclic = zx_dma_prep_dma_cyclic; + d->slave.device_issue_pending = zx_dma_issue_pending; + d->slave.device_config = zx_dma_config; + d->slave.device_terminate_all = zx_dma_terminate_all; + d->slave.device_pause = zx_dma_transfer_pause; + d->slave.device_resume = zx_dma_transfer_resume; + d->slave.copy_align = DMA_ALIGN; + d->slave.src_addr_widths = ZX_DMA_BUSWIDTHS; + d->slave.dst_addr_widths = ZX_DMA_BUSWIDTHS; + d->slave.directions = BIT(DMA_MEM_TO_MEM) | BIT(DMA_MEM_TO_DEV) + | BIT(DMA_DEV_TO_MEM); + d->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; + + /* init virtual channel */ + d->chans = devm_kzalloc(&op->dev, + d->dma_requests * sizeof(struct zx_dma_chan), GFP_KERNEL); + if (!d->chans) + return -ENOMEM; + + for (i = 0; i < d->dma_requests; i++) { + struct zx_dma_chan *c = &d->chans[i]; + + c->status = DMA_IN_PROGRESS; + INIT_LIST_HEAD(&c->node); + c->vc.desc_free = zx_dma_free_desc; + vchan_init(&c->vc, &d->slave); + } + + /* Enable clock before accessing registers */ + ret = clk_prepare_enable(d->clk); + if (ret < 0) { + dev_err(&op->dev, "clk_prepare_enable failed: %d\n", ret); + goto zx_dma_out; + } + + zx_dma_init_state(d); + + spin_lock_init(&d->lock); + INIT_LIST_HEAD(&d->chan_pending); + platform_set_drvdata(op, d); + + ret = dma_async_device_register(&d->slave); + if (ret) + goto clk_dis; + + ret = of_dma_controller_register((&op->dev)->of_node, + zx_of_dma_simple_xlate, d); + if (ret) + goto of_dma_register_fail; + + dev_info(&op->dev, "initialized\n"); + return 0; + +of_dma_register_fail: + dma_async_device_unregister(&d->slave); +clk_dis: + clk_disable_unprepare(d->clk); +zx_dma_out: + return ret; +} + +static int zx_dma_remove(struct platform_device *op) +{ + struct zx_dma_chan *c, *cn; + struct zx_dma_dev *d = platform_get_drvdata(op); + + /* explictly free the irq */ + devm_free_irq(&op->dev, d->irq, d); + + dma_async_device_unregister(&d->slave); + of_dma_controller_free((&op->dev)->of_node); + + list_for_each_entry_safe(c, cn, &d->slave.channels, + vc.chan.device_node) { + list_del(&c->vc.chan.device_node); + } + clk_disable_unprepare(d->clk); + dmam_pool_destroy(d->pool); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int zx_dma_suspend_dev(struct device *dev) +{ + struct zx_dma_dev *d = dev_get_drvdata(dev); + u32 stat = 0; + + stat = zx_dma_get_chan_stat(d); + if (stat) { + dev_warn(d->slave.dev, + "chan %d is running fail to suspend\n", stat); + return -1; + } + clk_disable_unprepare(d->clk); + return 0; +} + +static int zx_dma_resume_dev(struct device *dev) +{ + struct zx_dma_dev *d = dev_get_drvdata(dev); + int ret = 0; + + ret = clk_prepare_enable(d->clk); + if (ret < 0) { + dev_err(d->slave.dev, "clk_prepare_enable failed: %d\n", ret); + return ret; + } + zx_dma_init_state(d); + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(zx_dma_pmops, zx_dma_suspend_dev, zx_dma_resume_dev); + +static struct platform_driver zx_pdma_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = &zx_dma_pmops, + .of_match_table = zx6702_dma_dt_ids, + }, + .probe = zx_dma_probe, + .remove = zx_dma_remove, +}; + +module_platform_driver(zx_pdma_driver); + +MODULE_DESCRIPTION("ZTE ZX296702 DMA Driver"); +MODULE_AUTHOR("Jun Nie jun.nie@linaro.org"); +MODULE_LICENSE("GPL v2"); |