diff options
Diffstat (limited to 'drivers/dma/mmp_pdma.c')
| -rw-r--r-- | drivers/dma/mmp_pdma.c | 1151 |
1 files changed, 1151 insertions, 0 deletions
diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c new file mode 100644 index 0000000000..ebdfdcbb4f --- /dev/null +++ b/drivers/dma/mmp_pdma.c @@ -0,0 +1,1151 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2012 Marvell International Ltd. + */ + +#include <linux/err.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/dma-mapping.h> +#include <linux/slab.h> +#include <linux/dmaengine.h> +#include <linux/platform_device.h> +#include <linux/device.h> +#include <linux/platform_data/mmp_dma.h> +#include <linux/dmapool.h> +#include <linux/of_device.h> +#include <linux/of_dma.h> +#include <linux/of.h> + +#include "dmaengine.h" + +#define DCSR 0x0000 +#define DALGN 0x00a0 +#define DINT 0x00f0 +#define DDADR 0x0200 +#define DSADR(n) (0x0204 + ((n) << 4)) +#define DTADR(n) (0x0208 + ((n) << 4)) +#define DCMD 0x020c + +#define DCSR_RUN BIT(31) /* Run Bit (read / write) */ +#define DCSR_NODESC BIT(30) /* No-Descriptor Fetch (read / write) */ +#define DCSR_STOPIRQEN BIT(29) /* Stop Interrupt Enable (read / write) */ +#define DCSR_REQPEND BIT(8) /* Request Pending (read-only) */ +#define DCSR_STOPSTATE BIT(3) /* Stop State (read-only) */ +#define DCSR_ENDINTR BIT(2) /* End Interrupt (read / write) */ +#define DCSR_STARTINTR BIT(1) /* Start Interrupt (read / write) */ +#define DCSR_BUSERR BIT(0) /* Bus Error Interrupt (read / write) */ + +#define DCSR_EORIRQEN BIT(28) /* End of Receive Interrupt Enable (R/W) */ +#define DCSR_EORJMPEN BIT(27) /* Jump to next descriptor on EOR */ +#define DCSR_EORSTOPEN BIT(26) /* STOP on an EOR */ +#define DCSR_SETCMPST BIT(25) /* Set Descriptor Compare Status */ +#define DCSR_CLRCMPST BIT(24) /* Clear Descriptor Compare Status */ +#define DCSR_CMPST BIT(10) /* The Descriptor Compare Status */ +#define DCSR_EORINTR BIT(9) /* The end of Receive */ + +#define DRCMR(n) ((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2)) +#define DRCMR_MAPVLD BIT(7) /* Map Valid (read / write) */ +#define DRCMR_CHLNUM 0x1f /* mask for Channel Number (read / write) */ + +#define DDADR_DESCADDR 0xfffffff0 /* Address of next descriptor (mask) */ +#define DDADR_STOP BIT(0) /* Stop (read / write) */ + +#define DCMD_INCSRCADDR BIT(31) /* Source Address Increment Setting. */ +#define DCMD_INCTRGADDR BIT(30) /* Target Address Increment Setting. */ +#define DCMD_FLOWSRC BIT(29) /* Flow Control by the source. */ +#define DCMD_FLOWTRG BIT(28) /* Flow Control by the target. */ +#define DCMD_STARTIRQEN BIT(22) /* Start Interrupt Enable */ +#define DCMD_ENDIRQEN BIT(21) /* End Interrupt Enable */ +#define DCMD_ENDIAN BIT(18) /* Device Endian-ness. */ +#define DCMD_BURST8 (1 << 16) /* 8 byte burst */ +#define DCMD_BURST16 (2 << 16) /* 16 byte burst */ +#define DCMD_BURST32 (3 << 16) /* 32 byte burst */ +#define DCMD_WIDTH1 (1 << 14) /* 1 byte width */ +#define DCMD_WIDTH2 (2 << 14) /* 2 byte width (HalfWord) */ +#define DCMD_WIDTH4 (3 << 14) /* 4 byte width (Word) */ +#define DCMD_LENGTH 0x01fff /* length mask (max = 8K - 1) */ + +#define PDMA_MAX_DESC_BYTES DCMD_LENGTH + +struct mmp_pdma_desc_hw { + u32 ddadr; /* Points to the next descriptor + flags */ + u32 dsadr; /* DSADR value for the current transfer */ + u32 dtadr; /* DTADR value for the current transfer */ + u32 dcmd; /* DCMD value for the current transfer */ +} __aligned(32); + +struct mmp_pdma_desc_sw { + struct mmp_pdma_desc_hw desc; + struct list_head node; + struct list_head tx_list; + struct dma_async_tx_descriptor async_tx; +}; + +struct mmp_pdma_phy; + +struct mmp_pdma_chan { + struct device *dev; + struct dma_chan chan; + struct dma_async_tx_descriptor desc; + struct mmp_pdma_phy *phy; + enum dma_transfer_direction dir; + struct dma_slave_config slave_config; + + struct mmp_pdma_desc_sw *cyclic_first; /* first desc_sw if channel + * is in cyclic mode */ + + /* channel's basic info */ + struct tasklet_struct tasklet; + u32 dcmd; + u32 drcmr; + u32 dev_addr; + + /* list for desc */ + spinlock_t desc_lock; /* Descriptor list lock */ + struct list_head chain_pending; /* Link descriptors queue for pending */ + struct list_head chain_running; /* Link descriptors queue for running */ + bool idle; /* channel statue machine */ + bool byte_align; + + struct dma_pool *desc_pool; /* Descriptors pool */ +}; + +struct mmp_pdma_phy { + int idx; + void __iomem *base; + struct mmp_pdma_chan *vchan; +}; + +struct mmp_pdma_device { + int dma_channels; + void __iomem *base; + struct device *dev; + struct dma_device device; + struct mmp_pdma_phy *phy; + spinlock_t phy_lock; /* protect alloc/free phy channels */ +}; + +#define tx_to_mmp_pdma_desc(tx) \ + container_of(tx, struct mmp_pdma_desc_sw, async_tx) +#define to_mmp_pdma_desc(lh) \ + container_of(lh, struct mmp_pdma_desc_sw, node) +#define to_mmp_pdma_chan(dchan) \ + container_of(dchan, struct mmp_pdma_chan, chan) +#define to_mmp_pdma_dev(dmadev) \ + container_of(dmadev, struct mmp_pdma_device, device) + +static int mmp_pdma_config_write(struct dma_chan *dchan, + struct dma_slave_config *cfg, + enum dma_transfer_direction direction); + +static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr) +{ + u32 reg = (phy->idx << 4) + DDADR; + + writel(addr, phy->base + reg); +} + +static void enable_chan(struct mmp_pdma_phy *phy) +{ + u32 reg, dalgn; + + if (!phy->vchan) + return; + + reg = DRCMR(phy->vchan->drcmr); + writel(DRCMR_MAPVLD | phy->idx, phy->base + reg); + + dalgn = readl(phy->base + DALGN); + if (phy->vchan->byte_align) + dalgn |= 1 << phy->idx; + else + dalgn &= ~(1 << phy->idx); + writel(dalgn, phy->base + DALGN); + + reg = (phy->idx << 2) + DCSR; + writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg); +} + +static void disable_chan(struct mmp_pdma_phy *phy) +{ + u32 reg; + + if (!phy) + return; + + reg = (phy->idx << 2) + DCSR; + writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg); +} + +static int clear_chan_irq(struct mmp_pdma_phy *phy) +{ + u32 dcsr; + u32 dint = readl(phy->base + DINT); + u32 reg = (phy->idx << 2) + DCSR; + + if (!(dint & BIT(phy->idx))) + return -EAGAIN; + + /* clear irq */ + dcsr = readl(phy->base + reg); + writel(dcsr, phy->base + reg); + if ((dcsr & DCSR_BUSERR) && (phy->vchan)) + dev_warn(phy->vchan->dev, "DCSR_BUSERR\n"); + + return 0; +} + +static irqreturn_t mmp_pdma_chan_handler(int irq, void *dev_id) +{ + struct mmp_pdma_phy *phy = dev_id; + + if (clear_chan_irq(phy) != 0) + return IRQ_NONE; + + tasklet_schedule(&phy->vchan->tasklet); + return IRQ_HANDLED; +} + +static irqreturn_t mmp_pdma_int_handler(int irq, void *dev_id) +{ + struct mmp_pdma_device *pdev = dev_id; + struct mmp_pdma_phy *phy; + u32 dint = readl(pdev->base + DINT); + int i, ret; + int irq_num = 0; + + while (dint) { + i = __ffs(dint); + /* only handle interrupts belonging to pdma driver*/ + if (i >= pdev->dma_channels) + break; + dint &= (dint - 1); + phy = &pdev->phy[i]; + ret = mmp_pdma_chan_handler(irq, phy); + if (ret == IRQ_HANDLED) + irq_num++; + } + + if (irq_num) + return IRQ_HANDLED; + + return IRQ_NONE; +} + +/* lookup free phy channel as descending priority */ +static struct mmp_pdma_phy *lookup_phy(struct mmp_pdma_chan *pchan) +{ + int prio, i; + struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device); + struct mmp_pdma_phy *phy, *found = NULL; + unsigned long flags; + + /* + * dma channel priorities + * ch 0 - 3, 16 - 19 <--> (0) + * ch 4 - 7, 20 - 23 <--> (1) + * ch 8 - 11, 24 - 27 <--> (2) + * ch 12 - 15, 28 - 31 <--> (3) + */ + + spin_lock_irqsave(&pdev->phy_lock, flags); + for (prio = 0; prio <= ((pdev->dma_channels - 1) & 0xf) >> 2; prio++) { + for (i = 0; i < pdev->dma_channels; i++) { + if (prio != (i & 0xf) >> 2) + continue; + phy = &pdev->phy[i]; + if (!phy->vchan) { + phy->vchan = pchan; + found = phy; + goto out_unlock; + } + } + } + +out_unlock: + spin_unlock_irqrestore(&pdev->phy_lock, flags); + return found; +} + +static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan) +{ + struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device); + unsigned long flags; + u32 reg; + + if (!pchan->phy) + return; + + /* clear the channel mapping in DRCMR */ + reg = DRCMR(pchan->drcmr); + writel(0, pchan->phy->base + reg); + + spin_lock_irqsave(&pdev->phy_lock, flags); + pchan->phy->vchan = NULL; + pchan->phy = NULL; + spin_unlock_irqrestore(&pdev->phy_lock, flags); +} + +/* + * start_pending_queue - transfer any pending transactions + * pending list ==> running list + */ +static void start_pending_queue(struct mmp_pdma_chan *chan) +{ + struct mmp_pdma_desc_sw *desc; + + /* still in running, irq will start the pending list */ + if (!chan->idle) { + dev_dbg(chan->dev, "DMA controller still busy\n"); + return; + } + + if (list_empty(&chan->chain_pending)) { + /* chance to re-fetch phy channel with higher prio */ + mmp_pdma_free_phy(chan); + dev_dbg(chan->dev, "no pending list\n"); + return; + } + + if (!chan->phy) { + chan->phy = lookup_phy(chan); + if (!chan->phy) { + dev_dbg(chan->dev, "no free dma channel\n"); + return; + } + } + + /* + * pending -> running + * reintilize pending list + */ + desc = list_first_entry(&chan->chain_pending, + struct mmp_pdma_desc_sw, node); + list_splice_tail_init(&chan->chain_pending, &chan->chain_running); + + /* + * Program the descriptor's address into the DMA controller, + * then start the DMA transaction + */ + set_desc(chan->phy, desc->async_tx.phys); + enable_chan(chan->phy); + chan->idle = false; +} + + +/* desc->tx_list ==> pending list */ +static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(tx->chan); + struct mmp_pdma_desc_sw *desc = tx_to_mmp_pdma_desc(tx); + struct mmp_pdma_desc_sw *child; + unsigned long flags; + dma_cookie_t cookie = -EBUSY; + + spin_lock_irqsave(&chan->desc_lock, flags); + + list_for_each_entry(child, &desc->tx_list, node) { + cookie = dma_cookie_assign(&child->async_tx); + } + + /* softly link to pending list - desc->tx_list ==> pending list */ + list_splice_tail_init(&desc->tx_list, &chan->chain_pending); + + spin_unlock_irqrestore(&chan->desc_lock, flags); + + return cookie; +} + +static struct mmp_pdma_desc_sw * +mmp_pdma_alloc_descriptor(struct mmp_pdma_chan *chan) +{ + struct mmp_pdma_desc_sw *desc; + dma_addr_t pdesc; + + desc = dma_pool_zalloc(chan->desc_pool, GFP_ATOMIC, &pdesc); + if (!desc) { + dev_err(chan->dev, "out of memory for link descriptor\n"); + return NULL; + } + + INIT_LIST_HEAD(&desc->tx_list); + dma_async_tx_descriptor_init(&desc->async_tx, &chan->chan); + /* each desc has submit */ + desc->async_tx.tx_submit = mmp_pdma_tx_submit; + desc->async_tx.phys = pdesc; + + return desc; +} + +/* + * mmp_pdma_alloc_chan_resources - Allocate resources for DMA channel. + * + * This function will create a dma pool for descriptor allocation. + * Request irq only when channel is requested + * Return - The number of allocated descriptors. + */ + +static int mmp_pdma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + + if (chan->desc_pool) + return 1; + + chan->desc_pool = dma_pool_create(dev_name(&dchan->dev->device), + chan->dev, + sizeof(struct mmp_pdma_desc_sw), + __alignof__(struct mmp_pdma_desc_sw), + 0); + if (!chan->desc_pool) { + dev_err(chan->dev, "unable to allocate descriptor pool\n"); + return -ENOMEM; + } + + mmp_pdma_free_phy(chan); + chan->idle = true; + chan->dev_addr = 0; + return 1; +} + +static void mmp_pdma_free_desc_list(struct mmp_pdma_chan *chan, + struct list_head *list) +{ + struct mmp_pdma_desc_sw *desc, *_desc; + + list_for_each_entry_safe(desc, _desc, list, node) { + list_del(&desc->node); + dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys); + } +} + +static void mmp_pdma_free_chan_resources(struct dma_chan *dchan) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + unsigned long flags; + + spin_lock_irqsave(&chan->desc_lock, flags); + mmp_pdma_free_desc_list(chan, &chan->chain_pending); + mmp_pdma_free_desc_list(chan, &chan->chain_running); + spin_unlock_irqrestore(&chan->desc_lock, flags); + + dma_pool_destroy(chan->desc_pool); + chan->desc_pool = NULL; + chan->idle = true; + chan->dev_addr = 0; + mmp_pdma_free_phy(chan); + return; +} + +static struct dma_async_tx_descriptor * +mmp_pdma_prep_memcpy(struct dma_chan *dchan, + dma_addr_t dma_dst, dma_addr_t dma_src, + size_t len, unsigned long flags) +{ + struct mmp_pdma_chan *chan; + struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new; + size_t copy = 0; + + if (!dchan) + return NULL; + + if (!len) + return NULL; + + chan = to_mmp_pdma_chan(dchan); + chan->byte_align = false; + + if (!chan->dir) { + chan->dir = DMA_MEM_TO_MEM; + chan->dcmd = DCMD_INCTRGADDR | DCMD_INCSRCADDR; + chan->dcmd |= DCMD_BURST32; + } + + do { + /* Allocate the link descriptor from DMA pool */ + new = mmp_pdma_alloc_descriptor(chan); + if (!new) { + dev_err(chan->dev, "no memory for desc\n"); + goto fail; + } + + copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES); + if (dma_src & 0x7 || dma_dst & 0x7) + chan->byte_align = true; + + new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy); + new->desc.dsadr = dma_src; + new->desc.dtadr = dma_dst; + + if (!first) + first = new; + else + prev->desc.ddadr = new->async_tx.phys; + + new->async_tx.cookie = 0; + async_tx_ack(&new->async_tx); + + prev = new; + len -= copy; + + if (chan->dir == DMA_MEM_TO_DEV) { + dma_src += copy; + } else if (chan->dir == DMA_DEV_TO_MEM) { + dma_dst += copy; + } else if (chan->dir == DMA_MEM_TO_MEM) { + dma_src += copy; + dma_dst += copy; + } + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + } while (len); + + first->async_tx.flags = flags; /* client is in control of this ack */ + first->async_tx.cookie = -EBUSY; + + /* last desc and fire IRQ */ + new->desc.ddadr = DDADR_STOP; + new->desc.dcmd |= DCMD_ENDIRQEN; + + chan->cyclic_first = NULL; + + return &first->async_tx; + +fail: + if (first) + mmp_pdma_free_desc_list(chan, &first->tx_list); + return NULL; +} + +static struct dma_async_tx_descriptor * +mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, + unsigned int sg_len, enum dma_transfer_direction dir, + unsigned long flags, void *context) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL; + size_t len, avail; + struct scatterlist *sg; + dma_addr_t addr; + int i; + + if ((sgl == NULL) || (sg_len == 0)) + return NULL; + + chan->byte_align = false; + + mmp_pdma_config_write(dchan, &chan->slave_config, dir); + + for_each_sg(sgl, sg, sg_len, i) { + addr = sg_dma_address(sg); + avail = sg_dma_len(sgl); + + do { + len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES); + if (addr & 0x7) + chan->byte_align = true; + + /* allocate and populate the descriptor */ + new = mmp_pdma_alloc_descriptor(chan); + if (!new) { + dev_err(chan->dev, "no memory for desc\n"); + goto fail; + } + + new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len); + if (dir == DMA_MEM_TO_DEV) { + new->desc.dsadr = addr; + new->desc.dtadr = chan->dev_addr; + } else { + new->desc.dsadr = chan->dev_addr; + new->desc.dtadr = addr; + } + + if (!first) + first = new; + else + prev->desc.ddadr = new->async_tx.phys; + + new->async_tx.cookie = 0; + async_tx_ack(&new->async_tx); + prev = new; + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + + /* update metadata */ + addr += len; + avail -= len; + } while (avail); + } + + first->async_tx.cookie = -EBUSY; + first->async_tx.flags = flags; + + /* last desc and fire IRQ */ + new->desc.ddadr = DDADR_STOP; + new->desc.dcmd |= DCMD_ENDIRQEN; + + chan->dir = dir; + chan->cyclic_first = NULL; + + return &first->async_tx; + +fail: + if (first) + mmp_pdma_free_desc_list(chan, &first->tx_list); + return NULL; +} + +static struct dma_async_tx_descriptor * +mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan, + dma_addr_t buf_addr, size_t len, size_t period_len, + enum dma_transfer_direction direction, + unsigned long flags) +{ + struct mmp_pdma_chan *chan; + struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new; + dma_addr_t dma_src, dma_dst; + + if (!dchan || !len || !period_len) + return NULL; + + /* the buffer length must be a multiple of period_len */ + if (len % period_len != 0) + return NULL; + + if (period_len > PDMA_MAX_DESC_BYTES) + return NULL; + + chan = to_mmp_pdma_chan(dchan); + mmp_pdma_config_write(dchan, &chan->slave_config, direction); + + switch (direction) { + case DMA_MEM_TO_DEV: + dma_src = buf_addr; + dma_dst = chan->dev_addr; + break; + case DMA_DEV_TO_MEM: + dma_dst = buf_addr; + dma_src = chan->dev_addr; + break; + default: + dev_err(chan->dev, "Unsupported direction for cyclic DMA\n"); + return NULL; + } + + chan->dir = direction; + + do { + /* Allocate the link descriptor from DMA pool */ + new = mmp_pdma_alloc_descriptor(chan); + if (!new) { + dev_err(chan->dev, "no memory for desc\n"); + goto fail; + } + + new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN | + (DCMD_LENGTH & period_len)); + new->desc.dsadr = dma_src; + new->desc.dtadr = dma_dst; + + if (!first) + first = new; + else + prev->desc.ddadr = new->async_tx.phys; + + new->async_tx.cookie = 0; + async_tx_ack(&new->async_tx); + + prev = new; + len -= period_len; + + if (chan->dir == DMA_MEM_TO_DEV) + dma_src += period_len; + else + dma_dst += period_len; + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + } while (len); + + first->async_tx.flags = flags; /* client is in control of this ack */ + first->async_tx.cookie = -EBUSY; + + /* make the cyclic link */ + new->desc.ddadr = first->async_tx.phys; + chan->cyclic_first = first; + + return &first->async_tx; + +fail: + if (first) + mmp_pdma_free_desc_list(chan, &first->tx_list); + return NULL; +} + +static int mmp_pdma_config_write(struct dma_chan *dchan, + struct dma_slave_config *cfg, + enum dma_transfer_direction direction) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + u32 maxburst = 0, addr = 0; + enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED; + + if (!dchan) + return -EINVAL; + + if (direction == DMA_DEV_TO_MEM) { + chan->dcmd = DCMD_INCTRGADDR | DCMD_FLOWSRC; + maxburst = cfg->src_maxburst; + width = cfg->src_addr_width; + addr = cfg->src_addr; + } else if (direction == DMA_MEM_TO_DEV) { + chan->dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG; + maxburst = cfg->dst_maxburst; + width = cfg->dst_addr_width; + addr = cfg->dst_addr; + } + + if (width == DMA_SLAVE_BUSWIDTH_1_BYTE) + chan->dcmd |= DCMD_WIDTH1; + else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES) + chan->dcmd |= DCMD_WIDTH2; + else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES) + chan->dcmd |= DCMD_WIDTH4; + + if (maxburst == 8) + chan->dcmd |= DCMD_BURST8; + else if (maxburst == 16) + chan->dcmd |= DCMD_BURST16; + else if (maxburst == 32) + chan->dcmd |= DCMD_BURST32; + + chan->dir = direction; + chan->dev_addr = addr; + + return 0; +} + +static int mmp_pdma_config(struct dma_chan *dchan, + struct dma_slave_config *cfg) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + + memcpy(&chan->slave_config, cfg, sizeof(*cfg)); + return 0; +} + +static int mmp_pdma_terminate_all(struct dma_chan *dchan) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + unsigned long flags; + + if (!dchan) + return -EINVAL; + + disable_chan(chan->phy); + mmp_pdma_free_phy(chan); + spin_lock_irqsave(&chan->desc_lock, flags); + mmp_pdma_free_desc_list(chan, &chan->chain_pending); + mmp_pdma_free_desc_list(chan, &chan->chain_running); + spin_unlock_irqrestore(&chan->desc_lock, flags); + chan->idle = true; + + return 0; +} + +static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan, + dma_cookie_t cookie) +{ + struct mmp_pdma_desc_sw *sw; + u32 curr, residue = 0; + bool passed = false; + bool cyclic = chan->cyclic_first != NULL; + + /* + * If the channel does not have a phy pointer anymore, it has already + * been completed. Therefore, its residue is 0. + */ + if (!chan->phy) + return 0; + + if (chan->dir == DMA_DEV_TO_MEM) + curr = readl(chan->phy->base + DTADR(chan->phy->idx)); + else + curr = readl(chan->phy->base + DSADR(chan->phy->idx)); + + list_for_each_entry(sw, &chan->chain_running, node) { + u32 start, end, len; + + if (chan->dir == DMA_DEV_TO_MEM) + start = sw->desc.dtadr; + else + start = sw->desc.dsadr; + + len = sw->desc.dcmd & DCMD_LENGTH; + end = start + len; + + /* + * 'passed' will be latched once we found the descriptor which + * lies inside the boundaries of the curr pointer. All + * descriptors that occur in the list _after_ we found that + * partially handled descriptor are still to be processed and + * are hence added to the residual bytes counter. + */ + + if (passed) { + residue += len; + } else if (curr >= start && curr <= end) { + residue += end - curr; + passed = true; + } + + /* + * Descriptors that have the ENDIRQEN bit set mark the end of a + * transaction chain, and the cookie assigned with it has been + * returned previously from mmp_pdma_tx_submit(). + * + * In case we have multiple transactions in the running chain, + * and the cookie does not match the one the user asked us + * about, reset the state variables and start over. + * + * This logic does not apply to cyclic transactions, where all + * descriptors have the ENDIRQEN bit set, and for which we + * can't have multiple transactions on one channel anyway. + */ + if (cyclic || !(sw->desc.dcmd & DCMD_ENDIRQEN)) + continue; + + if (sw->async_tx.cookie == cookie) { + return residue; + } else { + residue = 0; + passed = false; + } + } + + /* We should only get here in case of cyclic transactions */ + return residue; +} + +static enum dma_status mmp_pdma_tx_status(struct dma_chan *dchan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + enum dma_status ret; + + ret = dma_cookie_status(dchan, cookie, txstate); + if (likely(ret != DMA_ERROR)) + dma_set_residue(txstate, mmp_pdma_residue(chan, cookie)); + + return ret; +} + +/* + * mmp_pdma_issue_pending - Issue the DMA start command + * pending list ==> running list + */ +static void mmp_pdma_issue_pending(struct dma_chan *dchan) +{ + struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan); + unsigned long flags; + + spin_lock_irqsave(&chan->desc_lock, flags); + start_pending_queue(chan); + spin_unlock_irqrestore(&chan->desc_lock, flags); +} + +/* + * dma_do_tasklet + * Do call back + * Start pending list + */ +static void dma_do_tasklet(struct tasklet_struct *t) +{ + struct mmp_pdma_chan *chan = from_tasklet(chan, t, tasklet); + struct mmp_pdma_desc_sw *desc, *_desc; + LIST_HEAD(chain_cleanup); + unsigned long flags; + struct dmaengine_desc_callback cb; + + if (chan->cyclic_first) { + spin_lock_irqsave(&chan->desc_lock, flags); + desc = chan->cyclic_first; + dmaengine_desc_get_callback(&desc->async_tx, &cb); + spin_unlock_irqrestore(&chan->desc_lock, flags); + + dmaengine_desc_callback_invoke(&cb, NULL); + + return; + } + + /* submit pending list; callback for each desc; free desc */ + spin_lock_irqsave(&chan->desc_lock, flags); + + list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) { + /* + * move the descriptors to a temporary list so we can drop + * the lock during the entire cleanup operation + */ + list_move(&desc->node, &chain_cleanup); + + /* + * Look for the first list entry which has the ENDIRQEN flag + * set. That is the descriptor we got an interrupt for, so + * complete that transaction and its cookie. + */ + if (desc->desc.dcmd & DCMD_ENDIRQEN) { + dma_cookie_t cookie = desc->async_tx.cookie; + dma_cookie_complete(&desc->async_tx); + dev_dbg(chan->dev, "completed_cookie=%d\n", cookie); + break; + } + } + + /* + * The hardware is idle and ready for more when the + * chain_running list is empty. + */ + chan->idle = list_empty(&chan->chain_running); + + /* Start any pending transactions automatically */ + start_pending_queue(chan); + spin_unlock_irqrestore(&chan->desc_lock, flags); + + /* Run the callback for each descriptor, in order */ + list_for_each_entry_safe(desc, _desc, &chain_cleanup, node) { + struct dma_async_tx_descriptor *txd = &desc->async_tx; + + /* Remove from the list of transactions */ + list_del(&desc->node); + /* Run the link descriptor callback function */ + dmaengine_desc_get_callback(txd, &cb); + dmaengine_desc_callback_invoke(&cb, NULL); + + dma_pool_free(chan->desc_pool, desc, txd->phys); + } +} + +static int mmp_pdma_remove(struct platform_device *op) +{ + struct mmp_pdma_device *pdev = platform_get_drvdata(op); + struct mmp_pdma_phy *phy; + int i, irq = 0, irq_num = 0; + + if (op->dev.of_node) + of_dma_controller_free(op->dev.of_node); + + for (i = 0; i < pdev->dma_channels; i++) { + if (platform_get_irq(op, i) > 0) + irq_num++; + } + + if (irq_num != pdev->dma_channels) { + irq = platform_get_irq(op, 0); + devm_free_irq(&op->dev, irq, pdev); + } else { + for (i = 0; i < pdev->dma_channels; i++) { + phy = &pdev->phy[i]; + irq = platform_get_irq(op, i); + devm_free_irq(&op->dev, irq, phy); + } + } + + dma_async_device_unregister(&pdev->device); + return 0; +} + +static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq) +{ + struct mmp_pdma_phy *phy = &pdev->phy[idx]; + struct mmp_pdma_chan *chan; + int ret; + + chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL); + if (chan == NULL) + return -ENOMEM; + + phy->idx = idx; + phy->base = pdev->base; + + if (irq) { + ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler, + IRQF_SHARED, "pdma", phy); + if (ret) { + dev_err(pdev->dev, "channel request irq fail!\n"); + return ret; + } + } + + spin_lock_init(&chan->desc_lock); + chan->dev = pdev->dev; + chan->chan.device = &pdev->device; + tasklet_setup(&chan->tasklet, dma_do_tasklet); + INIT_LIST_HEAD(&chan->chain_pending); + INIT_LIST_HEAD(&chan->chain_running); + + /* register virt channel to dma engine */ + list_add_tail(&chan->chan.device_node, &pdev->device.channels); + + return 0; +} + +static const struct of_device_id mmp_pdma_dt_ids[] = { + { .compatible = "marvell,pdma-1.0", }, + {} +}; +MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids); + +static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct mmp_pdma_device *d = ofdma->of_dma_data; + struct dma_chan *chan; + + chan = dma_get_any_slave_channel(&d->device); + if (!chan) + return NULL; + + to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0]; + + return chan; +} + +static int mmp_pdma_probe(struct platform_device *op) +{ + struct mmp_pdma_device *pdev; + const struct of_device_id *of_id; + struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev); + int i, ret, irq = 0; + int dma_channels = 0, irq_num = 0; + const enum dma_slave_buswidth widths = + DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES | + DMA_SLAVE_BUSWIDTH_4_BYTES; + + pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL); + if (!pdev) + return -ENOMEM; + + pdev->dev = &op->dev; + + spin_lock_init(&pdev->phy_lock); + + pdev->base = devm_platform_ioremap_resource(op, 0); + if (IS_ERR(pdev->base)) + return PTR_ERR(pdev->base); + + of_id = of_match_device(mmp_pdma_dt_ids, pdev->dev); + if (of_id) { + /* Parse new and deprecated dma-channels properties */ + if (of_property_read_u32(pdev->dev->of_node, "dma-channels", + &dma_channels)) + of_property_read_u32(pdev->dev->of_node, "#dma-channels", + &dma_channels); + } else if (pdata && pdata->dma_channels) { + dma_channels = pdata->dma_channels; + } else { + dma_channels = 32; /* default 32 channel */ + } + pdev->dma_channels = dma_channels; + + for (i = 0; i < dma_channels; i++) { + if (platform_get_irq_optional(op, i) > 0) + irq_num++; + } + + pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy), + GFP_KERNEL); + if (pdev->phy == NULL) + return -ENOMEM; + + INIT_LIST_HEAD(&pdev->device.channels); + + if (irq_num != dma_channels) { + /* all chan share one irq, demux inside */ + irq = platform_get_irq(op, 0); + ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler, + IRQF_SHARED, "pdma", pdev); + if (ret) + return ret; + } + + for (i = 0; i < dma_channels; i++) { + irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i); + ret = mmp_pdma_chan_init(pdev, i, irq); + if (ret) + return ret; + } + + dma_cap_set(DMA_SLAVE, pdev->device.cap_mask); + dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask); + dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask); + dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask); + pdev->device.dev = &op->dev; + pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources; + pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources; + pdev->device.device_tx_status = mmp_pdma_tx_status; + pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy; + pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg; + pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic; + pdev->device.device_issue_pending = mmp_pdma_issue_pending; + pdev->device.device_config = mmp_pdma_config; + pdev->device.device_terminate_all = mmp_pdma_terminate_all; + pdev->device.copy_align = DMAENGINE_ALIGN_8_BYTES; + pdev->device.src_addr_widths = widths; + pdev->device.dst_addr_widths = widths; + pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM); + pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; + + if (pdev->dev->coherent_dma_mask) + dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask); + else + dma_set_mask(pdev->dev, DMA_BIT_MASK(64)); + + ret = dma_async_device_register(&pdev->device); + if (ret) { + dev_err(pdev->device.dev, "unable to register\n"); + return ret; + } + + if (op->dev.of_node) { + /* Device-tree DMA controller registration */ + ret = of_dma_controller_register(op->dev.of_node, + mmp_pdma_dma_xlate, pdev); + if (ret < 0) { + dev_err(&op->dev, "of_dma_controller_register failed\n"); + dma_async_device_unregister(&pdev->device); + return ret; + } + } + + platform_set_drvdata(op, pdev); + dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels); + return 0; +} + +static const struct platform_device_id mmp_pdma_id_table[] = { + { "mmp-pdma", }, + { }, +}; + +static struct platform_driver mmp_pdma_driver = { + .driver = { + .name = "mmp-pdma", + .of_match_table = mmp_pdma_dt_ids, + }, + .id_table = mmp_pdma_id_table, + .probe = mmp_pdma_probe, + .remove = mmp_pdma_remove, +}; + +module_platform_driver(mmp_pdma_driver); + +MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver"); +MODULE_AUTHOR("Marvell International Ltd."); +MODULE_LICENSE("GPL v2"); |