diff options
Diffstat (limited to 'drivers/dma/sa11x0-dma.c')
| -rw-r--r-- | drivers/dma/sa11x0-dma.c | 1106 |
1 files changed, 1106 insertions, 0 deletions
diff --git a/drivers/dma/sa11x0-dma.c b/drivers/dma/sa11x0-dma.c new file mode 100644 index 000000000..43db25505 --- /dev/null +++ b/drivers/dma/sa11x0-dma.c @@ -0,0 +1,1106 @@ +/* + * SA11x0 DMAengine support + * + * Copyright (C) 2012 Russell King + * Derived in part from arch/arm/mach-sa1100/dma.c, + * Copyright (C) 2000, 2001 by Nicolas Pitre + * + * 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/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sa11x0-dma.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include "virt-dma.h" + +#define NR_PHY_CHAN 6 +#define DMA_ALIGN 3 +#define DMA_MAX_SIZE 0x1fff +#define DMA_CHUNK_SIZE 0x1000 + +#define DMA_DDAR 0x00 +#define DMA_DCSR_S 0x04 +#define DMA_DCSR_C 0x08 +#define DMA_DCSR_R 0x0c +#define DMA_DBSA 0x10 +#define DMA_DBTA 0x14 +#define DMA_DBSB 0x18 +#define DMA_DBTB 0x1c +#define DMA_SIZE 0x20 + +#define DCSR_RUN (1 << 0) +#define DCSR_IE (1 << 1) +#define DCSR_ERROR (1 << 2) +#define DCSR_DONEA (1 << 3) +#define DCSR_STRTA (1 << 4) +#define DCSR_DONEB (1 << 5) +#define DCSR_STRTB (1 << 6) +#define DCSR_BIU (1 << 7) + +#define DDAR_RW (1 << 0) /* 0 = W, 1 = R */ +#define DDAR_E (1 << 1) /* 0 = LE, 1 = BE */ +#define DDAR_BS (1 << 2) /* 0 = BS4, 1 = BS8 */ +#define DDAR_DW (1 << 3) /* 0 = 8b, 1 = 16b */ +#define DDAR_Ser0UDCTr (0x0 << 4) +#define DDAR_Ser0UDCRc (0x1 << 4) +#define DDAR_Ser1SDLCTr (0x2 << 4) +#define DDAR_Ser1SDLCRc (0x3 << 4) +#define DDAR_Ser1UARTTr (0x4 << 4) +#define DDAR_Ser1UARTRc (0x5 << 4) +#define DDAR_Ser2ICPTr (0x6 << 4) +#define DDAR_Ser2ICPRc (0x7 << 4) +#define DDAR_Ser3UARTTr (0x8 << 4) +#define DDAR_Ser3UARTRc (0x9 << 4) +#define DDAR_Ser4MCP0Tr (0xa << 4) +#define DDAR_Ser4MCP0Rc (0xb << 4) +#define DDAR_Ser4MCP1Tr (0xc << 4) +#define DDAR_Ser4MCP1Rc (0xd << 4) +#define DDAR_Ser4SSPTr (0xe << 4) +#define DDAR_Ser4SSPRc (0xf << 4) + +struct sa11x0_dma_sg { + u32 addr; + u32 len; +}; + +struct sa11x0_dma_desc { + struct virt_dma_desc vd; + + u32 ddar; + size_t size; + unsigned period; + bool cyclic; + + unsigned sglen; + struct sa11x0_dma_sg sg[0]; +}; + +struct sa11x0_dma_phy; + +struct sa11x0_dma_chan { + struct virt_dma_chan vc; + + /* protected by c->vc.lock */ + struct sa11x0_dma_phy *phy; + enum dma_status status; + + /* protected by d->lock */ + struct list_head node; + + u32 ddar; + const char *name; +}; + +struct sa11x0_dma_phy { + void __iomem *base; + struct sa11x0_dma_dev *dev; + unsigned num; + + struct sa11x0_dma_chan *vchan; + + /* Protected by c->vc.lock */ + unsigned sg_load; + struct sa11x0_dma_desc *txd_load; + unsigned sg_done; + struct sa11x0_dma_desc *txd_done; + u32 dbs[2]; + u32 dbt[2]; + u32 dcsr; +}; + +struct sa11x0_dma_dev { + struct dma_device slave; + void __iomem *base; + spinlock_t lock; + struct tasklet_struct task; + struct list_head chan_pending; + struct sa11x0_dma_phy phy[NR_PHY_CHAN]; +}; + +static struct sa11x0_dma_chan *to_sa11x0_dma_chan(struct dma_chan *chan) +{ + return container_of(chan, struct sa11x0_dma_chan, vc.chan); +} + +static struct sa11x0_dma_dev *to_sa11x0_dma(struct dma_device *dmadev) +{ + return container_of(dmadev, struct sa11x0_dma_dev, slave); +} + +static struct sa11x0_dma_desc *sa11x0_dma_next_desc(struct sa11x0_dma_chan *c) +{ + struct virt_dma_desc *vd = vchan_next_desc(&c->vc); + + return vd ? container_of(vd, struct sa11x0_dma_desc, vd) : NULL; +} + +static void sa11x0_dma_free_desc(struct virt_dma_desc *vd) +{ + kfree(container_of(vd, struct sa11x0_dma_desc, vd)); +} + +static void sa11x0_dma_start_desc(struct sa11x0_dma_phy *p, struct sa11x0_dma_desc *txd) +{ + list_del(&txd->vd.node); + p->txd_load = txd; + p->sg_load = 0; + + dev_vdbg(p->dev->slave.dev, "pchan %u: txd %p[%x]: starting: DDAR:%x\n", + p->num, &txd->vd, txd->vd.tx.cookie, txd->ddar); +} + +static void noinline sa11x0_dma_start_sg(struct sa11x0_dma_phy *p, + struct sa11x0_dma_chan *c) +{ + struct sa11x0_dma_desc *txd = p->txd_load; + struct sa11x0_dma_sg *sg; + void __iomem *base = p->base; + unsigned dbsx, dbtx; + u32 dcsr; + + if (!txd) + return; + + dcsr = readl_relaxed(base + DMA_DCSR_R); + + /* Don't try to load the next transfer if both buffers are started */ + if ((dcsr & (DCSR_STRTA | DCSR_STRTB)) == (DCSR_STRTA | DCSR_STRTB)) + return; + + if (p->sg_load == txd->sglen) { + if (!txd->cyclic) { + struct sa11x0_dma_desc *txn = sa11x0_dma_next_desc(c); + + /* + * We have reached the end of the current descriptor. + * Peek at the next descriptor, and if compatible with + * the current, start processing it. + */ + if (txn && txn->ddar == txd->ddar) { + txd = txn; + sa11x0_dma_start_desc(p, txn); + } else { + p->txd_load = NULL; + return; + } + } else { + /* Cyclic: reset back to beginning */ + p->sg_load = 0; + } + } + + sg = &txd->sg[p->sg_load++]; + + /* Select buffer to load according to channel status */ + if (((dcsr & (DCSR_BIU | DCSR_STRTB)) == (DCSR_BIU | DCSR_STRTB)) || + ((dcsr & (DCSR_BIU | DCSR_STRTA)) == 0)) { + dbsx = DMA_DBSA; + dbtx = DMA_DBTA; + dcsr = DCSR_STRTA | DCSR_IE | DCSR_RUN; + } else { + dbsx = DMA_DBSB; + dbtx = DMA_DBTB; + dcsr = DCSR_STRTB | DCSR_IE | DCSR_RUN; + } + + writel_relaxed(sg->addr, base + dbsx); + writel_relaxed(sg->len, base + dbtx); + writel(dcsr, base + DMA_DCSR_S); + + dev_dbg(p->dev->slave.dev, "pchan %u: load: DCSR:%02x DBS%c:%08x DBT%c:%08x\n", + p->num, dcsr, + 'A' + (dbsx == DMA_DBSB), sg->addr, + 'A' + (dbtx == DMA_DBTB), sg->len); +} + +static void noinline sa11x0_dma_complete(struct sa11x0_dma_phy *p, + struct sa11x0_dma_chan *c) +{ + struct sa11x0_dma_desc *txd = p->txd_done; + + if (++p->sg_done == txd->sglen) { + if (!txd->cyclic) { + vchan_cookie_complete(&txd->vd); + + p->sg_done = 0; + p->txd_done = p->txd_load; + + if (!p->txd_done) + tasklet_schedule(&p->dev->task); + } else { + if ((p->sg_done % txd->period) == 0) + vchan_cyclic_callback(&txd->vd); + + /* Cyclic: reset back to beginning */ + p->sg_done = 0; + } + } + + sa11x0_dma_start_sg(p, c); +} + +static irqreturn_t sa11x0_dma_irq(int irq, void *dev_id) +{ + struct sa11x0_dma_phy *p = dev_id; + struct sa11x0_dma_dev *d = p->dev; + struct sa11x0_dma_chan *c; + u32 dcsr; + + dcsr = readl_relaxed(p->base + DMA_DCSR_R); + if (!(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB))) + return IRQ_NONE; + + /* Clear reported status bits */ + writel_relaxed(dcsr & (DCSR_ERROR | DCSR_DONEA | DCSR_DONEB), + p->base + DMA_DCSR_C); + + dev_dbg(d->slave.dev, "pchan %u: irq: DCSR:%02x\n", p->num, dcsr); + + if (dcsr & DCSR_ERROR) { + dev_err(d->slave.dev, "pchan %u: error. DCSR:%02x DDAR:%08x DBSA:%08x DBTA:%08x DBSB:%08x DBTB:%08x\n", + p->num, dcsr, + readl_relaxed(p->base + DMA_DDAR), + readl_relaxed(p->base + DMA_DBSA), + readl_relaxed(p->base + DMA_DBTA), + readl_relaxed(p->base + DMA_DBSB), + readl_relaxed(p->base + DMA_DBTB)); + } + + c = p->vchan; + if (c) { + unsigned long flags; + + spin_lock_irqsave(&c->vc.lock, flags); + /* + * Now that we're holding the lock, check that the vchan + * really is associated with this pchan before touching the + * hardware. This should always succeed, because we won't + * change p->vchan or c->phy while the channel is actively + * transferring. + */ + if (c->phy == p) { + if (dcsr & DCSR_DONEA) + sa11x0_dma_complete(p, c); + if (dcsr & DCSR_DONEB) + sa11x0_dma_complete(p, c); + } + spin_unlock_irqrestore(&c->vc.lock, flags); + } + + return IRQ_HANDLED; +} + +static void sa11x0_dma_start_txd(struct sa11x0_dma_chan *c) +{ + struct sa11x0_dma_desc *txd = sa11x0_dma_next_desc(c); + + /* If the issued list is empty, we have no further txds to process */ + if (txd) { + struct sa11x0_dma_phy *p = c->phy; + + sa11x0_dma_start_desc(p, txd); + p->txd_done = txd; + p->sg_done = 0; + + /* The channel should not have any transfers started */ + WARN_ON(readl_relaxed(p->base + DMA_DCSR_R) & + (DCSR_STRTA | DCSR_STRTB)); + + /* Clear the run and start bits before changing DDAR */ + writel_relaxed(DCSR_RUN | DCSR_STRTA | DCSR_STRTB, + p->base + DMA_DCSR_C); + writel_relaxed(txd->ddar, p->base + DMA_DDAR); + + /* Try to start both buffers */ + sa11x0_dma_start_sg(p, c); + sa11x0_dma_start_sg(p, c); + } +} + +static void sa11x0_dma_tasklet(unsigned long arg) +{ + struct sa11x0_dma_dev *d = (struct sa11x0_dma_dev *)arg; + struct sa11x0_dma_phy *p; + struct sa11x0_dma_chan *c; + unsigned pch, pch_alloc = 0; + + dev_dbg(d->slave.dev, "tasklet enter\n"); + + list_for_each_entry(c, &d->slave.channels, vc.chan.device_node) { + spin_lock_irq(&c->vc.lock); + p = c->phy; + if (p && !p->txd_done) { + sa11x0_dma_start_txd(c); + if (!p->txd_done) { + /* No current txd associated with this channel */ + dev_dbg(d->slave.dev, "pchan %u: free\n", p->num); + + /* Mark this channel free */ + c->phy = NULL; + p->vchan = NULL; + } + } + spin_unlock_irq(&c->vc.lock); + } + + spin_lock_irq(&d->lock); + for (pch = 0; pch < NR_PHY_CHAN; pch++) { + p = &d->phy[pch]; + + if (p->vchan == NULL && !list_empty(&d->chan_pending)) { + c = list_first_entry(&d->chan_pending, + struct sa11x0_dma_chan, node); + list_del_init(&c->node); + + pch_alloc |= 1 << pch; + + /* Mark this channel allocated */ + p->vchan = c; + + dev_dbg(d->slave.dev, "pchan %u: alloc vchan %p\n", pch, &c->vc); + } + } + spin_unlock_irq(&d->lock); + + for (pch = 0; pch < NR_PHY_CHAN; pch++) { + if (pch_alloc & (1 << pch)) { + p = &d->phy[pch]; + c = p->vchan; + + spin_lock_irq(&c->vc.lock); + c->phy = p; + + sa11x0_dma_start_txd(c); + spin_unlock_irq(&c->vc.lock); + } + } + + dev_dbg(d->slave.dev, "tasklet exit\n"); +} + + +static void sa11x0_dma_free_chan_resources(struct dma_chan *chan) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_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); +} + +static dma_addr_t sa11x0_dma_pos(struct sa11x0_dma_phy *p) +{ + unsigned reg; + u32 dcsr; + + dcsr = readl_relaxed(p->base + DMA_DCSR_R); + + if ((dcsr & (DCSR_BIU | DCSR_STRTA)) == DCSR_STRTA || + (dcsr & (DCSR_BIU | DCSR_STRTB)) == DCSR_BIU) + reg = DMA_DBSA; + else + reg = DMA_DBSB; + + return readl_relaxed(p->base + reg); +} + +static enum dma_status sa11x0_dma_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, struct dma_tx_state *state) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); + struct sa11x0_dma_phy *p; + struct virt_dma_desc *vd; + unsigned long flags; + enum dma_status ret; + + ret = dma_cookie_status(&c->vc.chan, cookie, state); + if (ret == DMA_COMPLETE) + return ret; + + if (!state) + return c->status; + + spin_lock_irqsave(&c->vc.lock, flags); + p = c->phy; + + /* + * If the cookie is on our issue queue, then the residue is + * its total size. + */ + vd = vchan_find_desc(&c->vc, cookie); + if (vd) { + state->residue = container_of(vd, struct sa11x0_dma_desc, vd)->size; + } else if (!p) { + state->residue = 0; + } else { + struct sa11x0_dma_desc *txd; + size_t bytes = 0; + + if (p->txd_done && p->txd_done->vd.tx.cookie == cookie) + txd = p->txd_done; + else if (p->txd_load && p->txd_load->vd.tx.cookie == cookie) + txd = p->txd_load; + else + txd = NULL; + + ret = c->status; + if (txd) { + dma_addr_t addr = sa11x0_dma_pos(p); + unsigned i; + + dev_vdbg(d->slave.dev, "tx_status: addr:%x\n", addr); + + for (i = 0; i < txd->sglen; i++) { + dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x\n", + i, txd->sg[i].addr, txd->sg[i].len); + if (addr >= txd->sg[i].addr && + addr < txd->sg[i].addr + txd->sg[i].len) { + unsigned len; + + len = txd->sg[i].len - + (addr - txd->sg[i].addr); + dev_vdbg(d->slave.dev, "tx_status: [%u] +%x\n", + i, len); + bytes += len; + i++; + break; + } + } + for (; i < txd->sglen; i++) { + dev_vdbg(d->slave.dev, "tx_status: [%u] %x+%x ++\n", + i, txd->sg[i].addr, txd->sg[i].len); + bytes += txd->sg[i].len; + } + } + state->residue = bytes; + } + spin_unlock_irqrestore(&c->vc.lock, flags); + + dev_vdbg(d->slave.dev, "tx_status: bytes 0x%zx\n", state->residue); + + return ret; +} + +/* + * Move pending txds to the issued list, and re-init pending list. + * If not already pending, add this channel to the list of pending + * channels and trigger the tasklet to run. + */ +static void sa11x0_dma_issue_pending(struct dma_chan *chan) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); + unsigned long flags; + + spin_lock_irqsave(&c->vc.lock, flags); + if (vchan_issue_pending(&c->vc)) { + if (!c->phy) { + spin_lock(&d->lock); + if (list_empty(&c->node)) { + list_add_tail(&c->node, &d->chan_pending); + tasklet_schedule(&d->task); + 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); +} + +static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg( + struct dma_chan *chan, struct scatterlist *sg, unsigned int sglen, + enum dma_transfer_direction dir, unsigned long flags, void *context) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_desc *txd; + struct scatterlist *sgent; + unsigned i, j = sglen; + size_t size = 0; + + /* SA11x0 channels can only operate in their native direction */ + if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) { + dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n", + &c->vc, c->ddar, dir); + return NULL; + } + + /* Do not allow zero-sized txds */ + if (sglen == 0) + return NULL; + + for_each_sg(sg, sgent, sglen, i) { + dma_addr_t addr = sg_dma_address(sgent); + unsigned int len = sg_dma_len(sgent); + + if (len > DMA_MAX_SIZE) + j += DIV_ROUND_UP(len, DMA_MAX_SIZE & ~DMA_ALIGN) - 1; + if (addr & DMA_ALIGN) { + dev_dbg(chan->device->dev, "vchan %p: bad buffer alignment: %08x\n", + &c->vc, addr); + return NULL; + } + } + + txd = kzalloc(sizeof(*txd) + j * sizeof(txd->sg[0]), GFP_ATOMIC); + if (!txd) { + dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc); + return NULL; + } + + j = 0; + for_each_sg(sg, sgent, sglen, i) { + dma_addr_t addr = sg_dma_address(sgent); + unsigned len = sg_dma_len(sgent); + + size += len; + + do { + unsigned tlen = len; + + /* + * Check whether the transfer will fit. If not, try + * to split the transfer up such that we end up with + * equal chunks - but make sure that we preserve the + * alignment. This avoids small segments. + */ + if (tlen > DMA_MAX_SIZE) { + unsigned mult = DIV_ROUND_UP(tlen, + DMA_MAX_SIZE & ~DMA_ALIGN); + + tlen = (tlen / mult) & ~DMA_ALIGN; + } + + txd->sg[j].addr = addr; + txd->sg[j].len = tlen; + + addr += tlen; + len -= tlen; + j++; + } while (len); + } + + txd->ddar = c->ddar; + txd->size = size; + txd->sglen = j; + + dev_dbg(chan->device->dev, "vchan %p: txd %p: size %u nr %u\n", + &c->vc, &txd->vd, txd->size, txd->sglen); + + return vchan_tx_prep(&c->vc, &txd->vd, flags); +} + +static struct dma_async_tx_descriptor *sa11x0_dma_prep_dma_cyclic( + struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period, + enum dma_transfer_direction dir, unsigned long flags) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_desc *txd; + unsigned i, j, k, sglen, sgperiod; + + /* SA11x0 channels can only operate in their native direction */ + if (dir != (c->ddar & DDAR_RW ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV)) { + dev_err(chan->device->dev, "vchan %p: bad DMA direction: DDAR:%08x dir:%u\n", + &c->vc, c->ddar, dir); + return NULL; + } + + sgperiod = DIV_ROUND_UP(period, DMA_MAX_SIZE & ~DMA_ALIGN); + sglen = size * sgperiod / period; + + /* Do not allow zero-sized txds */ + if (sglen == 0) + return NULL; + + txd = kzalloc(sizeof(*txd) + sglen * sizeof(txd->sg[0]), GFP_ATOMIC); + if (!txd) { + dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc); + return NULL; + } + + for (i = k = 0; i < size / period; i++) { + size_t tlen, len = period; + + for (j = 0; j < sgperiod; j++, k++) { + tlen = len; + + if (tlen > DMA_MAX_SIZE) { + unsigned mult = DIV_ROUND_UP(tlen, DMA_MAX_SIZE & ~DMA_ALIGN); + tlen = (tlen / mult) & ~DMA_ALIGN; + } + + txd->sg[k].addr = addr; + txd->sg[k].len = tlen; + addr += tlen; + len -= tlen; + } + + WARN_ON(len != 0); + } + + WARN_ON(k != sglen); + + txd->ddar = c->ddar; + txd->size = size; + txd->sglen = sglen; + txd->cyclic = 1; + txd->period = sgperiod; + + return vchan_tx_prep(&c->vc, &txd->vd, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); +} + +static int sa11x0_dma_device_config(struct dma_chan *chan, + struct dma_slave_config *cfg) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + u32 ddar = c->ddar & ((0xf << 4) | DDAR_RW); + dma_addr_t addr; + enum dma_slave_buswidth width; + u32 maxburst; + + if (ddar & DDAR_RW) { + addr = cfg->src_addr; + width = cfg->src_addr_width; + maxburst = cfg->src_maxburst; + } else { + addr = cfg->dst_addr; + width = cfg->dst_addr_width; + maxburst = cfg->dst_maxburst; + } + + if ((width != DMA_SLAVE_BUSWIDTH_1_BYTE && + width != DMA_SLAVE_BUSWIDTH_2_BYTES) || + (maxburst != 4 && maxburst != 8)) + return -EINVAL; + + if (width == DMA_SLAVE_BUSWIDTH_2_BYTES) + ddar |= DDAR_DW; + if (maxburst == 8) + ddar |= DDAR_BS; + + dev_dbg(c->vc.chan.device->dev, "vchan %p: dma_slave_config addr %x width %u burst %u\n", + &c->vc, addr, width, maxburst); + + c->ddar = ddar | (addr & 0xf0000000) | (addr & 0x003ffffc) << 6; + + return 0; +} + +static int sa11x0_dma_device_pause(struct dma_chan *chan) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); + struct sa11x0_dma_phy *p; + LIST_HEAD(head); + unsigned long flags; + + dev_dbg(d->slave.dev, "vchan %p: pause\n", &c->vc); + spin_lock_irqsave(&c->vc.lock, flags); + if (c->status == DMA_IN_PROGRESS) { + c->status = DMA_PAUSED; + + p = c->phy; + if (p) { + writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C); + } else { + spin_lock(&d->lock); + list_del_init(&c->node); + spin_unlock(&d->lock); + } + } + spin_unlock_irqrestore(&c->vc.lock, flags); + + return 0; +} + +static int sa11x0_dma_device_resume(struct dma_chan *chan) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); + struct sa11x0_dma_phy *p; + LIST_HEAD(head); + unsigned long flags; + + dev_dbg(d->slave.dev, "vchan %p: resume\n", &c->vc); + spin_lock_irqsave(&c->vc.lock, flags); + if (c->status == DMA_PAUSED) { + c->status = DMA_IN_PROGRESS; + + p = c->phy; + if (p) { + writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_S); + } else if (!list_empty(&c->vc.desc_issued)) { + spin_lock(&d->lock); + list_add_tail(&c->node, &d->chan_pending); + spin_unlock(&d->lock); + } + } + spin_unlock_irqrestore(&c->vc.lock, flags); + + return 0; +} + +static int sa11x0_dma_device_terminate_all(struct dma_chan *chan) +{ + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + struct sa11x0_dma_dev *d = to_sa11x0_dma(chan->device); + struct sa11x0_dma_phy *p; + LIST_HEAD(head); + unsigned long flags; + + dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc); + /* Clear the tx descriptor lists */ + spin_lock_irqsave(&c->vc.lock, flags); + vchan_get_all_descriptors(&c->vc, &head); + + p = c->phy; + if (p) { + dev_dbg(d->slave.dev, "pchan %u: terminating\n", p->num); + /* vchan is assigned to a pchan - stop the channel */ + writel(DCSR_RUN | DCSR_IE | + DCSR_STRTA | DCSR_DONEA | + DCSR_STRTB | DCSR_DONEB, + p->base + DMA_DCSR_C); + + if (p->txd_load) { + if (p->txd_load != p->txd_done) + list_add_tail(&p->txd_load->vd.node, &head); + p->txd_load = NULL; + } + if (p->txd_done) { + list_add_tail(&p->txd_done->vd.node, &head); + p->txd_done = NULL; + } + c->phy = NULL; + spin_lock(&d->lock); + p->vchan = NULL; + spin_unlock(&d->lock); + tasklet_schedule(&d->task); + } + spin_unlock_irqrestore(&c->vc.lock, flags); + vchan_dma_desc_free_list(&c->vc, &head); + + return 0; +} + +struct sa11x0_dma_channel_desc { + u32 ddar; + const char *name; +}; + +#define CD(d1, d2) { .ddar = DDAR_##d1 | d2, .name = #d1 } +static const struct sa11x0_dma_channel_desc chan_desc[] = { + CD(Ser0UDCTr, 0), + CD(Ser0UDCRc, DDAR_RW), + CD(Ser1SDLCTr, 0), + CD(Ser1SDLCRc, DDAR_RW), + CD(Ser1UARTTr, 0), + CD(Ser1UARTRc, DDAR_RW), + CD(Ser2ICPTr, 0), + CD(Ser2ICPRc, DDAR_RW), + CD(Ser3UARTTr, 0), + CD(Ser3UARTRc, DDAR_RW), + CD(Ser4MCP0Tr, 0), + CD(Ser4MCP0Rc, DDAR_RW), + CD(Ser4MCP1Tr, 0), + CD(Ser4MCP1Rc, DDAR_RW), + CD(Ser4SSPTr, 0), + CD(Ser4SSPRc, DDAR_RW), +}; + +static int sa11x0_dma_init_dmadev(struct dma_device *dmadev, + struct device *dev) +{ + unsigned i; + + INIT_LIST_HEAD(&dmadev->channels); + dmadev->dev = dev; + dmadev->device_free_chan_resources = sa11x0_dma_free_chan_resources; + dmadev->device_config = sa11x0_dma_device_config; + dmadev->device_pause = sa11x0_dma_device_pause; + dmadev->device_resume = sa11x0_dma_device_resume; + dmadev->device_terminate_all = sa11x0_dma_device_terminate_all; + dmadev->device_tx_status = sa11x0_dma_tx_status; + dmadev->device_issue_pending = sa11x0_dma_issue_pending; + + for (i = 0; i < ARRAY_SIZE(chan_desc); i++) { + struct sa11x0_dma_chan *c; + + c = kzalloc(sizeof(*c), GFP_KERNEL); + if (!c) { + dev_err(dev, "no memory for channel %u\n", i); + return -ENOMEM; + } + + c->status = DMA_IN_PROGRESS; + c->ddar = chan_desc[i].ddar; + c->name = chan_desc[i].name; + INIT_LIST_HEAD(&c->node); + + c->vc.desc_free = sa11x0_dma_free_desc; + vchan_init(&c->vc, dmadev); + } + + return dma_async_device_register(dmadev); +} + +static int sa11x0_dma_request_irq(struct platform_device *pdev, int nr, + void *data) +{ + int irq = platform_get_irq(pdev, nr); + + if (irq <= 0) + return -ENXIO; + + return request_irq(irq, sa11x0_dma_irq, 0, dev_name(&pdev->dev), data); +} + +static void sa11x0_dma_free_irq(struct platform_device *pdev, int nr, + void *data) +{ + int irq = platform_get_irq(pdev, nr); + if (irq > 0) + free_irq(irq, data); +} + +static void sa11x0_dma_free_channels(struct dma_device *dmadev) +{ + struct sa11x0_dma_chan *c, *cn; + + list_for_each_entry_safe(c, cn, &dmadev->channels, vc.chan.device_node) { + list_del(&c->vc.chan.device_node); + tasklet_kill(&c->vc.task); + kfree(c); + } +} + +static int sa11x0_dma_probe(struct platform_device *pdev) +{ + struct sa11x0_dma_dev *d; + struct resource *res; + unsigned i; + int ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENXIO; + + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + ret = -ENOMEM; + goto err_alloc; + } + + spin_lock_init(&d->lock); + INIT_LIST_HEAD(&d->chan_pending); + + d->base = ioremap(res->start, resource_size(res)); + if (!d->base) { + ret = -ENOMEM; + goto err_ioremap; + } + + tasklet_init(&d->task, sa11x0_dma_tasklet, (unsigned long)d); + + for (i = 0; i < NR_PHY_CHAN; i++) { + struct sa11x0_dma_phy *p = &d->phy[i]; + + p->dev = d; + p->num = i; + p->base = d->base + i * DMA_SIZE; + writel_relaxed(DCSR_RUN | DCSR_IE | DCSR_ERROR | + DCSR_DONEA | DCSR_STRTA | DCSR_DONEB | DCSR_STRTB, + p->base + DMA_DCSR_C); + writel_relaxed(0, p->base + DMA_DDAR); + + ret = sa11x0_dma_request_irq(pdev, i, p); + if (ret) { + while (i) { + i--; + sa11x0_dma_free_irq(pdev, i, &d->phy[i]); + } + goto err_irq; + } + } + + dma_cap_set(DMA_SLAVE, d->slave.cap_mask); + dma_cap_set(DMA_CYCLIC, d->slave.cap_mask); + d->slave.device_prep_slave_sg = sa11x0_dma_prep_slave_sg; + d->slave.device_prep_dma_cyclic = sa11x0_dma_prep_dma_cyclic; + d->slave.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + d->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; + d->slave.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES); + d->slave.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES); + ret = sa11x0_dma_init_dmadev(&d->slave, &pdev->dev); + if (ret) { + dev_warn(d->slave.dev, "failed to register slave async device: %d\n", + ret); + goto err_slave_reg; + } + + platform_set_drvdata(pdev, d); + return 0; + + err_slave_reg: + sa11x0_dma_free_channels(&d->slave); + for (i = 0; i < NR_PHY_CHAN; i++) + sa11x0_dma_free_irq(pdev, i, &d->phy[i]); + err_irq: + tasklet_kill(&d->task); + iounmap(d->base); + err_ioremap: + kfree(d); + err_alloc: + return ret; +} + +static int sa11x0_dma_remove(struct platform_device *pdev) +{ + struct sa11x0_dma_dev *d = platform_get_drvdata(pdev); + unsigned pch; + + dma_async_device_unregister(&d->slave); + + sa11x0_dma_free_channels(&d->slave); + for (pch = 0; pch < NR_PHY_CHAN; pch++) + sa11x0_dma_free_irq(pdev, pch, &d->phy[pch]); + tasklet_kill(&d->task); + iounmap(d->base); + kfree(d); + + return 0; +} + +static int sa11x0_dma_suspend(struct device *dev) +{ + struct sa11x0_dma_dev *d = dev_get_drvdata(dev); + unsigned pch; + + for (pch = 0; pch < NR_PHY_CHAN; pch++) { + struct sa11x0_dma_phy *p = &d->phy[pch]; + u32 dcsr, saved_dcsr; + + dcsr = saved_dcsr = readl_relaxed(p->base + DMA_DCSR_R); + if (dcsr & DCSR_RUN) { + writel(DCSR_RUN | DCSR_IE, p->base + DMA_DCSR_C); + dcsr = readl_relaxed(p->base + DMA_DCSR_R); + } + + saved_dcsr &= DCSR_RUN | DCSR_IE; + if (dcsr & DCSR_BIU) { + p->dbs[0] = readl_relaxed(p->base + DMA_DBSB); + p->dbt[0] = readl_relaxed(p->base + DMA_DBTB); + p->dbs[1] = readl_relaxed(p->base + DMA_DBSA); + p->dbt[1] = readl_relaxed(p->base + DMA_DBTA); + saved_dcsr |= (dcsr & DCSR_STRTA ? DCSR_STRTB : 0) | + (dcsr & DCSR_STRTB ? DCSR_STRTA : 0); + } else { + p->dbs[0] = readl_relaxed(p->base + DMA_DBSA); + p->dbt[0] = readl_relaxed(p->base + DMA_DBTA); + p->dbs[1] = readl_relaxed(p->base + DMA_DBSB); + p->dbt[1] = readl_relaxed(p->base + DMA_DBTB); + saved_dcsr |= dcsr & (DCSR_STRTA | DCSR_STRTB); + } + p->dcsr = saved_dcsr; + + writel(DCSR_STRTA | DCSR_STRTB, p->base + DMA_DCSR_C); + } + + return 0; +} + +static int sa11x0_dma_resume(struct device *dev) +{ + struct sa11x0_dma_dev *d = dev_get_drvdata(dev); + unsigned pch; + + for (pch = 0; pch < NR_PHY_CHAN; pch++) { + struct sa11x0_dma_phy *p = &d->phy[pch]; + struct sa11x0_dma_desc *txd = NULL; + u32 dcsr = readl_relaxed(p->base + DMA_DCSR_R); + + WARN_ON(dcsr & (DCSR_BIU | DCSR_STRTA | DCSR_STRTB | DCSR_RUN)); + + if (p->txd_done) + txd = p->txd_done; + else if (p->txd_load) + txd = p->txd_load; + + if (!txd) + continue; + + writel_relaxed(txd->ddar, p->base + DMA_DDAR); + + writel_relaxed(p->dbs[0], p->base + DMA_DBSA); + writel_relaxed(p->dbt[0], p->base + DMA_DBTA); + writel_relaxed(p->dbs[1], p->base + DMA_DBSB); + writel_relaxed(p->dbt[1], p->base + DMA_DBTB); + writel_relaxed(p->dcsr, p->base + DMA_DCSR_S); + } + + return 0; +} + +static const struct dev_pm_ops sa11x0_dma_pm_ops = { + .suspend_noirq = sa11x0_dma_suspend, + .resume_noirq = sa11x0_dma_resume, + .freeze_noirq = sa11x0_dma_suspend, + .thaw_noirq = sa11x0_dma_resume, + .poweroff_noirq = sa11x0_dma_suspend, + .restore_noirq = sa11x0_dma_resume, +}; + +static struct platform_driver sa11x0_dma_driver = { + .driver = { + .name = "sa11x0-dma", + .pm = &sa11x0_dma_pm_ops, + }, + .probe = sa11x0_dma_probe, + .remove = sa11x0_dma_remove, +}; + +bool sa11x0_dma_filter_fn(struct dma_chan *chan, void *param) +{ + if (chan->device->dev->driver == &sa11x0_dma_driver.driver) { + struct sa11x0_dma_chan *c = to_sa11x0_dma_chan(chan); + const char *p = param; + + return !strcmp(c->name, p); + } + return false; +} +EXPORT_SYMBOL(sa11x0_dma_filter_fn); + +static int __init sa11x0_dma_init(void) +{ + return platform_driver_register(&sa11x0_dma_driver); +} +subsys_initcall(sa11x0_dma_init); + +static void __exit sa11x0_dma_exit(void) +{ + platform_driver_unregister(&sa11x0_dma_driver); +} +module_exit(sa11x0_dma_exit); + +MODULE_AUTHOR("Russell King"); +MODULE_DESCRIPTION("SA-11x0 DMA driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:sa11x0-dma"); |