/* * Copyright (c) 2006 ARM Ltd. * Copyright (c) 2010 ST-Ericsson SA * * Author: Peter Pearse * Author: Linus Walleij * * 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. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * The full GNU General Public License is in this distribution in the file * called COPYING. * * Documentation: ARM DDI 0196G == PL080 * Documentation: ARM DDI 0218E == PL081 * * PL080 & PL081 both have 16 sets of DMA signals that can be routed to any * channel. * * The PL080 has 8 channels available for simultaneous use, and the PL081 * has only two channels. So on these DMA controllers the number of channels * and the number of incoming DMA signals are two totally different things. * It is usually not possible to theoretically handle all physical signals, * so a multiplexing scheme with possible denial of use is necessary. * * The PL080 has a dual bus master, PL081 has a single master. * * Memory to peripheral transfer may be visualized as * Get data from memory to DMAC * Until no data left * On burst request from peripheral * Destination burst from DMAC to peripheral * Clear burst request * Raise terminal count interrupt * * For peripherals with a FIFO: * Source burst size == half the depth of the peripheral FIFO * Destination burst size == the depth of the peripheral FIFO * * (Bursts are irrelevant for mem to mem transfers - there are no burst * signals, the DMA controller will simply facilitate its AHB master.) * * ASSUMES default (little) endianness for DMA transfers * * The PL08x has two flow control settings: * - DMAC flow control: the transfer size defines the number of transfers * which occur for the current LLI entry, and the DMAC raises TC at the * end of every LLI entry. Observed behaviour shows the DMAC listening * to both the BREQ and SREQ signals (contrary to documented), * transferring data if either is active. The LBREQ and LSREQ signals * are ignored. * * - Peripheral flow control: the transfer size is ignored (and should be * zero). The data is transferred from the current LLI entry, until * after the final transfer signalled by LBREQ or LSREQ. The DMAC * will then move to the next LLI entry. * * Global TODO: * - Break out common code from arch/arm/mach-s3c64xx and share */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dmaengine.h" #define DRIVER_NAME "pl08xdmac" static struct amba_driver pl08x_amba_driver; struct pl08x_driver_data; /** * struct vendor_data - vendor-specific config parameters for PL08x derivatives * @channels: the number of channels available in this variant * @dualmaster: whether this version supports dual AHB masters or not. * @nomadik: whether the channels have Nomadik security extension bits * that need to be checked for permission before use and some registers are * missing */ struct vendor_data { u8 channels; bool dualmaster; bool nomadik; }; /* * PL08X private data structures * An LLI struct - see PL08x TRM. Note that next uses bit[0] as a bus bit, * start & end do not - their bus bit info is in cctl. Also note that these * are fixed 32-bit quantities. */ struct pl08x_lli { u32 src; u32 dst; u32 lli; u32 cctl; }; /** * struct pl08x_bus_data - information of source or destination * busses for a transfer * @addr: current address * @maxwidth: the maximum width of a transfer on this bus * @buswidth: the width of this bus in bytes: 1, 2 or 4 */ struct pl08x_bus_data { dma_addr_t addr; u8 maxwidth; u8 buswidth; }; /** * struct pl08x_phy_chan - holder for the physical channels * @id: physical index to this channel * @lock: a lock to use when altering an instance of this struct * @signal: the physical signal (aka channel) serving this physical channel * right now * @serving: the virtual channel currently being served by this physical * channel */ struct pl08x_phy_chan { unsigned int id; void __iomem *base; spinlock_t lock; int signal; struct pl08x_dma_chan *serving; }; /** * struct pl08x_sg - structure containing data per sg * @src_addr: src address of sg * @dst_addr: dst address of sg * @len: transfer len in bytes * @node: node for txd's dsg_list */ struct pl08x_sg { dma_addr_t src_addr; dma_addr_t dst_addr; size_t len; struct list_head node; }; /** * struct pl08x_txd - wrapper for struct dma_async_tx_descriptor * @tx: async tx descriptor * @node: node for txd list for channels * @dsg_list: list of children sg's * @direction: direction of transfer * @llis_bus: DMA memory address (physical) start for the LLIs * @llis_va: virtual memory address start for the LLIs * @cctl: control reg values for current txd * @ccfg: config reg values for current txd */ struct pl08x_txd { struct dma_async_tx_descriptor tx; struct list_head node; struct list_head dsg_list; enum dma_transfer_direction direction; dma_addr_t llis_bus; struct pl08x_lli *llis_va; /* Default cctl value for LLIs */ u32 cctl; /* * Settings to be put into the physical channel when we * trigger this txd. Other registers are in llis_va[0]. */ u32 ccfg; }; /** * struct pl08x_dma_chan_state - holds the PL08x specific virtual channel * states * @PL08X_CHAN_IDLE: the channel is idle * @PL08X_CHAN_RUNNING: the channel has allocated a physical transport * channel and is running a transfer on it * @PL08X_CHAN_PAUSED: the channel has allocated a physical transport * channel, but the transfer is currently paused * @PL08X_CHAN_WAITING: the channel is waiting for a physical transport * channel to become available (only pertains to memcpy channels) */ enum pl08x_dma_chan_state { PL08X_CHAN_IDLE, PL08X_CHAN_RUNNING, PL08X_CHAN_PAUSED, PL08X_CHAN_WAITING, }; /** * struct pl08x_dma_chan - this structure wraps a DMA ENGINE channel * @chan: wrappped abstract channel * @phychan: the physical channel utilized by this channel, if there is one * @phychan_hold: if non-zero, hold on to the physical channel even if we * have no pending entries * @tasklet: tasklet scheduled by the IRQ to handle actual work etc * @name: name of channel * @cd: channel platform data * @runtime_addr: address for RX/TX according to the runtime config * @runtime_direction: current direction of this channel according to * runtime config * @pend_list: queued transactions pending on this channel * @at: active transaction on this channel * @lock: a lock for this channel data * @host: a pointer to the host (internal use) * @state: whether the channel is idle, paused, running etc * @slave: whether this channel is a device (slave) or for memcpy * @device_fc: Flow Controller Settings for ccfg register. Only valid for slave * channels. Fill with 'true' if peripheral should be flow controller. Direction * will be selected at Runtime. * @waiting: a TX descriptor on this channel which is waiting for a physical * channel to become available */ struct pl08x_dma_chan { struct dma_chan chan; struct pl08x_phy_chan *phychan; int phychan_hold; struct tasklet_struct tasklet; char *name; const struct pl08x_channel_data *cd; dma_addr_t src_addr; dma_addr_t dst_addr; u32 src_cctl; u32 dst_cctl; enum dma_transfer_direction runtime_direction; struct list_head pend_list; struct pl08x_txd *at; spinlock_t lock; struct pl08x_driver_data *host; enum pl08x_dma_chan_state state; bool slave; bool device_fc; struct pl08x_txd *waiting; }; /** * struct pl08x_driver_data - the local state holder for the PL08x * @slave: slave engine for this instance * @memcpy: memcpy engine for this instance * @base: virtual memory base (remapped) for the PL08x * @adev: the corresponding AMBA (PrimeCell) bus entry * @vd: vendor data for this PL08x variant * @pd: platform data passed in from the platform/machine * @phy_chans: array of data for the physical channels * @pool: a pool for the LLI descriptors * @pool_ctr: counter of LLIs in the pool * @lli_buses: bitmask to or in to LLI pointer selecting AHB port for LLI * fetches * @mem_buses: set to indicate memory transfers on AHB2. * @lock: a spinlock for this struct */ struct pl08x_driver_data { struct dma_device slave; struct dma_device memcpy; void __iomem *base; struct amba_device *adev; const struct vendor_data *vd; struct pl08x_platform_data *pd; struct pl08x_phy_chan *phy_chans; struct dma_pool *pool; int pool_ctr; u8 lli_buses; u8 mem_buses; }; /* * PL08X specific defines */ /* Size (bytes) of each LLI buffer allocated for one transfer */ # define PL08X_LLI_TSFR_SIZE 0x2000 /* Maximum times we call dma_pool_alloc on this pool without freeing */ #define MAX_NUM_TSFR_LLIS (PL08X_LLI_TSFR_SIZE/sizeof(struct pl08x_lli)) #define PL08X_ALIGN 8 static inline struct pl08x_dma_chan *to_pl08x_chan(struct dma_chan *chan) { return container_of(chan, struct pl08x_dma_chan, chan); } static inline struct pl08x_txd *to_pl08x_txd(struct dma_async_tx_descriptor *tx) { return container_of(tx, struct pl08x_txd, tx); } /* * Physical channel handling */ /* Whether a certain channel is busy or not */ static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch) { unsigned int val; val = readl(ch->base + PL080_CH_CONFIG); return val & PL080_CONFIG_ACTIVE; } /* * Set the initial DMA register values i.e. those for the first LLI * The next LLI pointer and the configuration interrupt bit have * been set when the LLIs were constructed. Poke them into the hardware * and start the transfer. */ static void pl08x_start_txd(struct pl08x_dma_chan *plchan, struct pl08x_txd *txd) { struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_phy_chan *phychan = plchan->phychan; struct pl08x_lli *lli = &txd->llis_va[0]; u32 val; plchan->at = txd; /* Wait for channel inactive */ while (pl08x_phy_channel_busy(phychan)) cpu_relax(); dev_vdbg(&pl08x->adev->dev, "WRITE channel %d: csrc=0x%08x, cdst=0x%08x, " "clli=0x%08x, cctl=0x%08x, ccfg=0x%08x\n", phychan->id, lli->src, lli->dst, lli->lli, lli->cctl, txd->ccfg); writel(lli->src, phychan->base + PL080_CH_SRC_ADDR); writel(lli->dst, phychan->base + PL080_CH_DST_ADDR); writel(lli->lli, phychan->base + PL080_CH_LLI); writel(lli->cctl, phychan->base + PL080_CH_CONTROL); writel(txd->ccfg, phychan->base + PL080_CH_CONFIG); /* Enable the DMA channel */ /* Do not access config register until channel shows as disabled */ while (readl(pl08x->base + PL080_EN_CHAN) & (1 << phychan->id)) cpu_relax(); /* Do not access config register until channel shows as inactive */ val = readl(phychan->base + PL080_CH_CONFIG); while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE)) val = readl(phychan->base + PL080_CH_CONFIG); writel(val | PL080_CONFIG_ENABLE, phychan->base + PL080_CH_CONFIG); } /* * Pause the channel by setting the HALT bit. * * For M->P transfers, pause the DMAC first and then stop the peripheral - * the FIFO can only drain if the peripheral is still requesting data. * (note: this can still timeout if the DMAC FIFO never drains of data.) * * For P->M transfers, disable the peripheral first to stop it filling * the DMAC FIFO, and then pause the DMAC. */ static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch) { u32 val; int timeout; /* Set the HALT bit and wait for the FIFO to drain */ val = readl(ch->base + PL080_CH_CONFIG); val |= PL080_CONFIG_HALT; writel(val, ch->base + PL080_CH_CONFIG); /* Wait for channel inactive */ for (timeout = 1000; timeout; timeout--) { if (!pl08x_phy_channel_busy(ch)) break; udelay(1); } if (pl08x_phy_channel_busy(ch)) pr_err("pl08x: channel%u timeout waiting for pause\n", ch->id); } static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch) { u32 val; /* Clear the HALT bit */ val = readl(ch->base + PL080_CH_CONFIG); val &= ~PL080_CONFIG_HALT; writel(val, ch->base + PL080_CH_CONFIG); } /* * pl08x_terminate_phy_chan() stops the channel, clears the FIFO and * clears any pending interrupt status. This should not be used for * an on-going transfer, but as a method of shutting down a channel * (eg, when it's no longer used) or terminating a transfer. */ static void pl08x_terminate_phy_chan(struct pl08x_driver_data *pl08x, struct pl08x_phy_chan *ch) { u32 val = readl(ch->base + PL080_CH_CONFIG); val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK | PL080_CONFIG_TC_IRQ_MASK); writel(val, ch->base + PL080_CH_CONFIG); writel(1 << ch->id, pl08x->base + PL080_ERR_CLEAR); writel(1 << ch->id, pl08x->base + PL080_TC_CLEAR); } static inline u32 get_bytes_in_cctl(u32 cctl) { /* The source width defines the number of bytes */ u32 bytes = cctl & PL080_CONTROL_TRANSFER_SIZE_MASK; switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) { case PL080_WIDTH_8BIT: break; case PL080_WIDTH_16BIT: bytes *= 2; break; case PL080_WIDTH_32BIT: bytes *= 4; break; } return bytes; } /* The channel should be paused when calling this */ static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan) { struct pl08x_phy_chan *ch; struct pl08x_txd *txd; unsigned long flags; size_t bytes = 0; spin_lock_irqsave(&plchan->lock, flags); ch = plchan->phychan; txd = plchan->at; /* * Follow the LLIs to get the number of remaining * bytes in the currently active transaction. */ if (ch && txd) { u32 clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2; /* First get the remaining bytes in the active transfer */ bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL)); if (clli) { struct pl08x_lli *llis_va = txd->llis_va; dma_addr_t llis_bus = txd->llis_bus; int index; BUG_ON(clli < llis_bus || clli >= llis_bus + sizeof(struct pl08x_lli) * MAX_NUM_TSFR_LLIS); /* * Locate the next LLI - as this is an array, * it's simple maths to find. */ index = (clli - llis_bus) / sizeof(struct pl08x_lli); for (; index < MAX_NUM_TSFR_LLIS; index++) { bytes += get_bytes_in_cctl(llis_va[index].cctl); /* * A LLI pointer of 0 terminates the LLI list */ if (!llis_va[index].lli) break; } } } /* Sum up all queued transactions */ if (!list_empty(&plchan->pend_list)) { struct pl08x_txd *txdi; list_for_each_entry(txdi, &plchan->pend_list, node) { struct pl08x_sg *dsg; list_for_each_entry(dsg, &txd->dsg_list, node) bytes += dsg->len; } } spin_unlock_irqrestore(&plchan->lock, flags); return bytes; } /* * Allocate a physical channel for a virtual channel * * Try to locate a physical channel to be used for this transfer. If all * are taken return NULL and the requester will have to cope by using * some fallback PIO mode or retrying later. */ static struct pl08x_phy_chan * pl08x_get_phy_channel(struct pl08x_driver_data *pl08x, struct pl08x_dma_chan *virt_chan) { struct pl08x_phy_chan *ch = NULL; unsigned long flags; int i; for (i = 0; i < pl08x->vd->channels; i++) { ch = &pl08x->phy_chans[i]; spin_lock_irqsave(&ch->lock, flags); if (!ch->locked && !ch->serving) { ch->serving = virt_chan; ch->signal = -1; spin_unlock_irqrestore(&ch->lock, flags); break; } spin_unlock_irqrestore(&ch->lock, flags); } if (i == pl08x->vd->channels) { /* No physical channel available, cope with it */ return NULL; } return ch; } static inline void pl08x_put_phy_channel(struct pl08x_driver_data *pl08x, struct pl08x_phy_chan *ch) { unsigned long flags; spin_lock_irqsave(&ch->lock, flags); /* Stop the channel and clear its interrupts */ pl08x_terminate_phy_chan(pl08x, ch); /* Mark it as free */ ch->serving = NULL; spin_unlock_irqrestore(&ch->lock, flags); } /* * LLI handling */ static inline unsigned int pl08x_get_bytes_for_cctl(unsigned int coded) { switch (coded) { case PL080_WIDTH_8BIT: return 1; case PL080_WIDTH_16BIT: return 2; case PL080_WIDTH_32BIT: return 4; default: break; } BUG(); return 0; } static inline u32 pl08x_cctl_bits(u32 cctl, u8 srcwidth, u8 dstwidth, size_t tsize) { u32 retbits = cctl; /* Remove all src, dst and transfer size bits */ retbits &= ~PL080_CONTROL_DWIDTH_MASK; retbits &= ~PL080_CONTROL_SWIDTH_MASK; retbits &= ~PL080_CONTROL_TRANSFER_SIZE_MASK; /* Then set the bits according to the parameters */ switch (srcwidth) { case 1: retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT; break; case 2: retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT; break; case 4: retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT; break; default: BUG(); break; } switch (dstwidth) { case 1: retbits |= PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT; break; case 2: retbits |= PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT; break; case 4: retbits |= PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT; break; default: BUG(); break; } retbits |= tsize << PL080_CONTROL_TRANSFER_SIZE_SHIFT; return retbits; } struct pl08x_lli_build_data { struct pl08x_txd *txd; struct pl08x_bus_data srcbus; struct pl08x_bus_data dstbus; size_t remainder; u32 lli_bus; }; /* * Autoselect a master bus to use for the transfer. Slave will be the chosen as * victim in case src & dest are not similarly aligned. i.e. If after aligning * masters address with width requirements of transfer (by sending few byte by * byte data), slave is still not aligned, then its width will be reduced to * BYTE. * - prefers the destination bus if both available * - prefers bus with fixed address (i.e. peripheral) */ static void pl08x_choose_master_bus(struct pl08x_lli_build_data *bd, struct pl08x_bus_data **mbus, struct pl08x_bus_data **sbus, u32 cctl) { if (!(cctl & PL080_CONTROL_DST_INCR)) { *mbus = &bd->dstbus; *sbus = &bd->srcbus; } else if (!(cctl & PL080_CONTROL_SRC_INCR)) { *mbus = &bd->srcbus; *sbus = &bd->dstbus; } else { if (bd->dstbus.buswidth >= bd->srcbus.buswidth) { *mbus = &bd->dstbus; *sbus = &bd->srcbus; } else { *mbus = &bd->srcbus; *sbus = &bd->dstbus; } } } /* * Fills in one LLI for a certain transfer descriptor and advance the counter */ static void pl08x_fill_lli_for_desc(struct pl08x_lli_build_data *bd, int num_llis, int len, u32 cctl) { struct pl08x_lli *llis_va = bd->txd->llis_va; dma_addr_t llis_bus = bd->txd->llis_bus; BUG_ON(num_llis >= MAX_NUM_TSFR_LLIS); llis_va[num_llis].cctl = cctl; llis_va[num_llis].src = bd->srcbus.addr; llis_va[num_llis].dst = bd->dstbus.addr; llis_va[num_llis].lli = llis_bus + (num_llis + 1) * sizeof(struct pl08x_lli); llis_va[num_llis].lli |= bd->lli_bus; if (cctl & PL080_CONTROL_SRC_INCR) bd->srcbus.addr += len; if (cctl & PL080_CONTROL_DST_INCR) bd->dstbus.addr += len; BUG_ON(bd->remainder < len); bd->remainder -= len; } static inline void prep_byte_width_lli(struct pl08x_lli_build_data *bd, u32 *cctl, u32 len, int num_llis, size_t *total_bytes) { *cctl = pl08x_cctl_bits(*cctl, 1, 1, len); pl08x_fill_lli_for_desc(bd, num_llis, len, *cctl); (*total_bytes) += len; } /* * This fills in the table of LLIs for the transfer descriptor * Note that we assume we never have to change the burst sizes * Return 0 for error */ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x, struct pl08x_txd *txd) { struct pl08x_bus_data *mbus, *sbus; struct pl08x_lli_build_data bd; int num_llis = 0; u32 cctl, early_bytes = 0; size_t max_bytes_per_lli, total_bytes; struct pl08x_lli *llis_va; struct pl08x_sg *dsg; txd->llis_va = dma_pool_alloc(pl08x->pool, GFP_NOWAIT, &txd->llis_bus); if (!txd->llis_va) { dev_err(&pl08x->adev->dev, "%s no memory for llis\n", __func__); return 0; } pl08x->pool_ctr++; bd.txd = txd; bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0; cctl = txd->cctl; /* Find maximum width of the source bus */ bd.srcbus.maxwidth = pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_SWIDTH_MASK) >> PL080_CONTROL_SWIDTH_SHIFT); /* Find maximum width of the destination bus */ bd.dstbus.maxwidth = pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_DWIDTH_MASK) >> PL080_CONTROL_DWIDTH_SHIFT); list_for_each_entry(dsg, &txd->dsg_list, node) { total_bytes = 0; cctl = txd->cctl; bd.srcbus.addr = dsg->src_addr; bd.dstbus.addr = dsg->dst_addr; bd.remainder = dsg->len; bd.srcbus.buswidth = bd.srcbus.maxwidth; bd.dstbus.buswidth = bd.dstbus.maxwidth; pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl); dev_vdbg(&pl08x->adev->dev, "src=0x%08x%s/%u dst=0x%08x%s/%u len=%zu\n", bd.srcbus.addr, cctl & PL080_CONTROL_SRC_INCR ? "+" : "", bd.srcbus.buswidth, bd.dstbus.addr, cctl & PL080_CONTROL_DST_INCR ? "+" : "", bd.dstbus.buswidth, bd.remainder); dev_vdbg(&pl08x->adev->dev, "mbus=%s sbus=%s\n", mbus == &bd.srcbus ? "src" : "dst", sbus == &bd.srcbus ? "src" : "dst"); /* * Zero length is only allowed if all these requirements are * met: * - flow controller is peripheral. * - src.addr is aligned to src.width * - dst.addr is aligned to dst.width * * sg_len == 1 should be true, as there can be two cases here: * * - Memory addresses are contiguous and are not scattered. * Here, Only one sg will be passed by user driver, with * memory address and zero length. We pass this to controller * and after the transfer it will receive the last burst * request from peripheral and so transfer finishes. * * - Memory addresses are scattered and are not contiguous. * Here, Obviously as DMA controller doesn't know when a lli's * transfer gets over, it can't load next lli. So in this * case, there has to be an assumption that only one lli is * supported. Thus, we can't have scattered addresses. */ if (!bd.remainder) { u32 fc = (txd->ccfg & PL080_CONFIG_FLOW_CONTROL_MASK) >> PL080_CONFIG_FLOW_CONTROL_SHIFT; if (!((fc >= PL080_FLOW_SRC2DST_DST) && (fc <= PL080_FLOW_SRC2DST_SRC))) { dev_err(&pl08x->adev->dev, "%s sg len can't be zero", __func__); return 0; } if ((bd.srcbus.addr % bd.srcbus.buswidth) || (bd.dstbus.addr % bd.dstbus.buswidth)) { dev_err(&pl08x->adev->dev, "%s src & dst address must be aligned to src" " & dst width if peripheral is flow controller", __func__); return 0; } cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth, bd.dstbus.buswidth, 0); pl08x_fill_lli_for_desc(&bd, num_llis++, 0, cctl); break; } /* * Send byte by byte for following cases * - Less than a bus width available * - until master bus is aligned */ if (bd.remainder < mbus->buswidth) early_bytes = bd.remainder; else if ((mbus->addr) % (mbus->buswidth)) { early_bytes = mbus->buswidth - (mbus->addr) % (mbus->buswidth); if ((bd.remainder - early_bytes) < mbus->buswidth) early_bytes = bd.remainder; } if (early_bytes) { dev_vdbg(&pl08x->adev->dev, "%s byte width LLIs (remain 0x%08x)\n", __func__, bd.remainder); prep_byte_width_lli(&bd, &cctl, early_bytes, num_llis++, &total_bytes); } if (bd.remainder) { /* * Master now aligned * - if slave is not then we must set its width down */ if (sbus->addr % sbus->buswidth) { dev_dbg(&pl08x->adev->dev, "%s set down bus width to one byte\n", __func__); sbus->buswidth = 1; } /* * Bytes transferred = tsize * src width, not * MIN(buswidths) */ max_bytes_per_lli = bd.srcbus.buswidth * PL080_CONTROL_TRANSFER_SIZE_MASK; dev_vdbg(&pl08x->adev->dev, "%s max bytes per lli = %zu\n", __func__, max_bytes_per_lli); /* * Make largest possible LLIs until less than one bus * width left */ while (bd.remainder > (mbus->buswidth - 1)) { size_t lli_len, tsize, width; /* * If enough left try to send max possible, * otherwise try to send the remainder */ lli_len = min(bd.remainder, max_bytes_per_lli); /* * Check against maximum bus alignment: * Calculate actual transfer size in relation to * bus width an get a maximum remainder of the * highest bus width - 1 */ width = max(mbus->buswidth, sbus->buswidth); lli_len = (lli_len / width) * width; tsize = lli_len / bd.srcbus.buswidth; dev_vdbg(&pl08x->adev->dev, "%s fill lli with single lli chunk of " "size 0x%08zx (remainder 0x%08zx)\n", __func__, lli_len, bd.remainder); cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth, bd.dstbus.buswidth, tsize); pl08x_fill_lli_for_desc(&bd, num_llis++, lli_len, cctl); total_bytes += lli_len; } /* * Send any odd bytes */ if (bd.remainder) { dev_vdbg(&pl08x->adev->dev, "%s align with boundary, send odd bytes (remain %zu)\n", __func__, bd.remainder); prep_byte_width_lli(&bd, &cctl, bd.remainder, num_llis++, &total_bytes); } } if (total_bytes != dsg->len) { dev_err(&pl08x->adev->dev, "%s size of encoded lli:s don't match total txd, transferred 0x%08zx from size 0x%08zx\n", __func__, total_bytes, dsg->len); return 0; } if (num_llis >= MAX_NUM_TSFR_LLIS) { dev_err(&pl08x->adev->dev, "%s need to increase MAX_NUM_TSFR_LLIS from 0x%08x\n", __func__, (u32) MAX_NUM_TSFR_LLIS); return 0; } } llis_va = txd->llis_va; /* The final LLI terminates the LLI. */ llis_va[num_llis - 1].lli = 0; /* The final LLI element shall also fire an interrupt. */ llis_va[num_llis - 1].cctl |= PL080_CONTROL_TC_IRQ_EN; #ifdef VERBOSE_DEBUG { int i; dev_vdbg(&pl08x->adev->dev, "%-3s %-9s %-10s %-10s %-10s %s\n", "lli", "", "csrc", "cdst", "clli", "cctl"); for (i = 0; i < num_llis; i++) { dev_vdbg(&pl08x->adev->dev, "%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x\n", i, &llis_va[i], llis_va[i].src, llis_va[i].dst, llis_va[i].lli, llis_va[i].cctl ); } } #endif return num_llis; } /* You should call this with the struct pl08x lock held */ static void pl08x_free_txd(struct pl08x_driver_data *pl08x, struct pl08x_txd *txd) { struct pl08x_sg *dsg, *_dsg; /* Free the LLI */ if (txd->llis_va) dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus); pl08x->pool_ctr--; list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) { list_del(&dsg->node); kfree(dsg); } kfree(txd); } static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x, struct pl08x_dma_chan *plchan) { struct pl08x_txd *txdi = NULL; struct pl08x_txd *next; if (!list_empty(&plchan->pend_list)) { list_for_each_entry_safe(txdi, next, &plchan->pend_list, node) { list_del(&txdi->node); pl08x_free_txd(pl08x, txdi); } } } /* * The DMA ENGINE API */ static int pl08x_alloc_chan_resources(struct dma_chan *chan) { return 0; } static void pl08x_free_chan_resources(struct dma_chan *chan) { } /* * This should be called with the channel plchan->lock held */ static int prep_phy_channel(struct pl08x_dma_chan *plchan, struct pl08x_txd *txd) { struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_phy_chan *ch; int ret; /* Check if we already have a channel */ if (plchan->phychan) { ch = plchan->phychan; goto got_channel; } ch = pl08x_get_phy_channel(pl08x, plchan); if (!ch) { /* No physical channel available, cope with it */ dev_dbg(&pl08x->adev->dev, "no physical channel available for xfer on %s\n", plchan->name); return -EBUSY; } /* * OK we have a physical channel: for memcpy() this is all we * need, but for slaves the physical signals may be muxed! * Can the platform allow us to use this channel? */ if (plchan->slave && pl08x->pd->get_signal) { ret = pl08x->pd->get_signal(plchan->cd); if (ret < 0) { dev_dbg(&pl08x->adev->dev, "unable to use physical channel %d for transfer on %s due to platform restrictions\n", ch->id, plchan->name); /* Release physical channel & return */ pl08x_put_phy_channel(pl08x, ch); return -EBUSY; } ch->signal = ret; } plchan->phychan = ch; dev_dbg(&pl08x->adev->dev, "allocated physical channel %d and signal %d for xfer on %s\n", ch->id, ch->signal, plchan->name); got_channel: /* Assign the flow control signal to this channel */ if (txd->direction == DMA_MEM_TO_DEV) txd->ccfg |= ch->signal << PL080_CONFIG_DST_SEL_SHIFT; else if (txd->direction == DMA_DEV_TO_MEM) txd->ccfg |= ch->signal << PL080_CONFIG_SRC_SEL_SHIFT; plchan->phychan_hold++; return 0; } static void release_phy_channel(struct pl08x_dma_chan *plchan) { struct pl08x_driver_data *pl08x = plchan->host; if ((plchan->phychan->signal >= 0) && pl08x->pd->put_signal) { pl08x->pd->put_signal(plchan->cd, plchan->phychan->signal); plchan->phychan->signal = -1; } pl08x_put_phy_channel(pl08x, plchan->phychan); plchan->phychan = NULL; } static dma_cookie_t pl08x_tx_submit(struct dma_async_tx_descriptor *tx) { struct pl08x_dma_chan *plchan = to_pl08x_chan(tx->chan); struct pl08x_txd *txd = to_pl08x_txd(tx); unsigned long flags; dma_cookie_t cookie; spin_lock_irqsave(&plchan->lock, flags); cookie = dma_cookie_assign(tx); /* Put this onto the pending list */ list_add_tail(&txd->node, &plchan->pend_list); /* * If there was no physical channel available for this memcpy, * stack the request up and indicate that the channel is waiting * for a free physical channel. */ if (!plchan->slave && !plchan->phychan) { /* Do this memcpy whenever there is a channel ready */ plchan->state = PL08X_CHAN_WAITING; plchan->waiting = txd; } else { plchan->phychan_hold--; } spin_unlock_irqrestore(&plchan->lock, flags); return cookie; } static struct dma_async_tx_descriptor *pl08x_prep_dma_interrupt( struct dma_chan *chan, unsigned long flags) { struct dma_async_tx_descriptor *retval = NULL; return retval; } /* * Code accessing dma_async_is_complete() in a tight loop may give problems. * If slaves are relying on interrupts to signal completion this function * must not be called with interrupts disabled. */ static enum dma_status pl08x_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); enum dma_status ret; ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_SUCCESS) return ret; /* * This cookie not complete yet * Get number of bytes left in the active transactions and queue */ dma_set_residue(txstate, pl08x_getbytes_chan(plchan)); if (plchan->state == PL08X_CHAN_PAUSED) return DMA_PAUSED; /* Whether waiting or running, we're in progress */ return DMA_IN_PROGRESS; } /* PrimeCell DMA extension */ struct burst_table { u32 burstwords; u32 reg; }; static const struct burst_table burst_sizes[] = { { .burstwords = 256, .reg = PL080_BSIZE_256, }, { .burstwords = 128, .reg = PL080_BSIZE_128, }, { .burstwords = 64, .reg = PL080_BSIZE_64, }, { .burstwords = 32, .reg = PL080_BSIZE_32, }, { .burstwords = 16, .reg = PL080_BSIZE_16, }, { .burstwords = 8, .reg = PL080_BSIZE_8, }, { .burstwords = 4, .reg = PL080_BSIZE_4, }, { .burstwords = 0, .reg = PL080_BSIZE_1, }, }; /* * Given the source and destination available bus masks, select which * will be routed to each port. We try to have source and destination * on separate ports, but always respect the allowable settings. */ static u32 pl08x_select_bus(u8 src, u8 dst) { u32 cctl = 0; if (!(dst & PL08X_AHB1) || ((dst & PL08X_AHB2) && (src & PL08X_AHB1))) cctl |= PL080_CONTROL_DST_AHB2; if (!(src & PL08X_AHB1) || ((src & PL08X_AHB2) && !(dst & PL08X_AHB2))) cctl |= PL080_CONTROL_SRC_AHB2; return cctl; } static u32 pl08x_cctl(u32 cctl) { cctl &= ~(PL080_CONTROL_SRC_AHB2 | PL080_CONTROL_DST_AHB2 | PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR | PL080_CONTROL_PROT_MASK); /* Access the cell in privileged mode, non-bufferable, non-cacheable */ return cctl | PL080_CONTROL_PROT_SYS; } static u32 pl08x_width(enum dma_slave_buswidth width) { switch (width) { case DMA_SLAVE_BUSWIDTH_1_BYTE: return PL080_WIDTH_8BIT; case DMA_SLAVE_BUSWIDTH_2_BYTES: return PL080_WIDTH_16BIT; case DMA_SLAVE_BUSWIDTH_4_BYTES: return PL080_WIDTH_32BIT; default: return ~0; } } static u32 pl08x_burst(u32 maxburst) { int i; for (i = 0; i < ARRAY_SIZE(burst_sizes); i++) if (burst_sizes[i].burstwords <= maxburst) break; return burst_sizes[i].reg; } static int dma_set_runtime_config(struct dma_chan *chan, struct dma_slave_config *config) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); struct pl08x_driver_data *pl08x = plchan->host; enum dma_slave_buswidth addr_width; u32 width, burst, maxburst; u32 cctl = 0; if (!plchan->slave) return -EINVAL; /* Transfer direction */ plchan->runtime_direction = config->direction; if (config->direction == DMA_MEM_TO_DEV) { addr_width = config->dst_addr_width; maxburst = config->dst_maxburst; } else if (config->direction == DMA_DEV_TO_MEM) { addr_width = config->src_addr_width; maxburst = config->src_maxburst; } else { dev_err(&pl08x->adev->dev, "bad runtime_config: alien transfer direction\n"); return -EINVAL; } width = pl08x_width(addr_width); if (width == ~0) { dev_err(&pl08x->adev->dev, "bad runtime_config: alien address width\n"); return -EINVAL; } cctl |= width << PL080_CONTROL_SWIDTH_SHIFT; cctl |= width << PL080_CONTROL_DWIDTH_SHIFT; /* * If this channel will only request single transfers, set this * down to ONE element. Also select one element if no maxburst * is specified. */ if (plchan->cd->single) maxburst = 1; burst = pl08x_burst(maxburst); cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT; cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT; plchan->device_fc = config->device_fc; if (plchan->runtime_direction == DMA_DEV_TO_MEM) { plchan->src_addr = config->src_addr; plchan->src_cctl = pl08x_cctl(cctl) | PL080_CONTROL_DST_INCR | pl08x_select_bus(plchan->cd->periph_buses, pl08x->mem_buses); } else { plchan->dst_addr = config->dst_addr; plchan->dst_cctl = pl08x_cctl(cctl) | PL080_CONTROL_SRC_INCR | pl08x_select_bus(pl08x->mem_buses, plchan->cd->periph_buses); } dev_dbg(&pl08x->adev->dev, "configured channel %s (%s) for %s, data width %d, " "maxburst %d words, LE, CCTL=0x%08x\n", dma_chan_name(chan), plchan->name, (config->direction == DMA_DEV_TO_MEM) ? "RX" : "TX", addr_width, maxburst, cctl); return 0; } /* * Slave transactions callback to the slave device to allow * synchronization of slave DMA signals with the DMAC enable */ static void pl08x_issue_pending(struct dma_chan *chan) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); unsigned long flags; spin_lock_irqsave(&plchan->lock, flags); /* Something is already active, or we're waiting for a channel... */ if (plchan->at || plchan->state == PL08X_CHAN_WAITING) { spin_unlock_irqrestore(&plchan->lock, flags); return; } /* Take the first element in the queue and execute it */ if (!list_empty(&plchan->pend_list)) { struct pl08x_txd *next; next = list_first_entry(&plchan->pend_list, struct pl08x_txd, node); list_del(&next->node); plchan->state = PL08X_CHAN_RUNNING; pl08x_start_txd(plchan, next); } spin_unlock_irqrestore(&plchan->lock, flags); } static int pl08x_prep_channel_resources(struct pl08x_dma_chan *plchan, struct pl08x_txd *txd) { struct pl08x_driver_data *pl08x = plchan->host; unsigned long flags; int num_llis, ret; num_llis = pl08x_fill_llis_for_desc(pl08x, txd); if (!num_llis) { spin_lock_irqsave(&plchan->lock, flags); pl08x_free_txd(pl08x, txd); spin_unlock_irqrestore(&plchan->lock, flags); return -EINVAL; } spin_lock_irqsave(&plchan->lock, flags); /* * See if we already have a physical channel allocated, * else this is the time to try to get one. */ ret = prep_phy_channel(plchan, txd); if (ret) { /* * No physical channel was available. * * memcpy transfers can be sorted out at submission time. * * Slave transfers may have been denied due to platform * channel muxing restrictions. Since there is no guarantee * that this will ever be resolved, and the signal must be * acquired AFTER acquiring the physical channel, we will let * them be NACK:ed with -EBUSY here. The drivers can retry * the prep() call if they are eager on doing this using DMA. */ if (plchan->slave) { pl08x_free_txd_list(pl08x, plchan); pl08x_free_txd(pl08x, txd); spin_unlock_irqrestore(&plchan->lock, flags); return -EBUSY; } } else /* * Else we're all set, paused and ready to roll, status * will switch to PL08X_CHAN_RUNNING when we call * issue_pending(). If there is something running on the * channel already we don't change its state. */ if (plchan->state == PL08X_CHAN_IDLE) plchan->state = PL08X_CHAN_PAUSED; spin_unlock_irqrestore(&plchan->lock, flags); return 0; } static struct pl08x_txd *pl08x_get_txd(struct pl08x_dma_chan *plchan, unsigned long flags) { struct pl08x_txd *txd = kzalloc(sizeof(*txd), GFP_NOWAIT); if (txd) { dma_async_tx_descriptor_init(&txd->tx, &plchan->chan); txd->tx.flags = flags; txd->tx.tx_submit = pl08x_tx_submit; INIT_LIST_HEAD(&txd->node); INIT_LIST_HEAD(&txd->dsg_list); /* Always enable error and terminal interrupts */ txd->ccfg = PL080_CONFIG_ERR_IRQ_MASK | PL080_CONFIG_TC_IRQ_MASK; } return txd; } /* * Initialize a descriptor to be used by memcpy submit */ static struct dma_async_tx_descriptor *pl08x_prep_dma_memcpy( struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_txd *txd; struct pl08x_sg *dsg; int ret; txd = pl08x_get_txd(plchan, flags); if (!txd) { dev_err(&pl08x->adev->dev, "%s no memory for descriptor\n", __func__); return NULL; } dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT); if (!dsg) { pl08x_free_txd(pl08x, txd); dev_err(&pl08x->adev->dev, "%s no memory for pl080 sg\n", __func__); return NULL; } list_add_tail(&dsg->node, &txd->dsg_list); txd->direction = DMA_MEM_TO_MEM; dsg->src_addr = src; dsg->dst_addr = dest; dsg->len = len; /* Set platform data for m2m */ txd->ccfg |= PL080_FLOW_MEM2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT; txd->cctl = pl08x->pd->memcpy_channel.cctl & ~(PL080_CONTROL_DST_AHB2 | PL080_CONTROL_SRC_AHB2); /* Both to be incremented or the code will break */ txd->cctl |= PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR; if (pl08x->vd->dualmaster) txd->cctl |= pl08x_select_bus(pl08x->mem_buses, pl08x->mem_buses); ret = pl08x_prep_channel_resources(plchan, txd); if (ret) return NULL; return &txd->tx; } static struct dma_async_tx_descriptor *pl08x_prep_slave_sg( struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_txd *txd; struct pl08x_sg *dsg; struct scatterlist *sg; dma_addr_t slave_addr; int ret, tmp; dev_dbg(&pl08x->adev->dev, "%s prepare transaction of %d bytes from %s\n", __func__, sg_dma_len(sgl), plchan->name); txd = pl08x_get_txd(plchan, flags); if (!txd) { dev_err(&pl08x->adev->dev, "%s no txd\n", __func__); return NULL; } if (direction != plchan->runtime_direction) dev_err(&pl08x->adev->dev, "%s DMA setup does not match " "the direction configured for the PrimeCell\n", __func__); /* * Set up addresses, the PrimeCell configured address * will take precedence since this may configure the * channel target address dynamically at runtime. */ txd->direction = direction; if (direction == DMA_MEM_TO_DEV) { txd->cctl = plchan->dst_cctl; slave_addr = plchan->dst_addr; } else if (direction == DMA_DEV_TO_MEM) { txd->cctl = plchan->src_cctl; slave_addr = plchan->src_addr; } else { pl08x_free_txd(pl08x, txd); dev_err(&pl08x->adev->dev, "%s direction unsupported\n", __func__); return NULL; } if (plchan->device_fc) tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER_PER : PL080_FLOW_PER2MEM_PER; else tmp = (direction == DMA_MEM_TO_DEV) ? PL080_FLOW_MEM2PER : PL080_FLOW_PER2MEM; txd->ccfg |= tmp << PL080_CONFIG_FLOW_CONTROL_SHIFT; for_each_sg(sgl, sg, sg_len, tmp) { dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT); if (!dsg) { pl08x_free_txd(pl08x, txd); dev_err(&pl08x->adev->dev, "%s no mem for pl080 sg\n", __func__); return NULL; } list_add_tail(&dsg->node, &txd->dsg_list); dsg->len = sg_dma_len(sg); if (direction == DMA_MEM_TO_DEV) { dsg->src_addr = sg_dma_address(sg); dsg->dst_addr = slave_addr; } else { dsg->src_addr = slave_addr; dsg->dst_addr = sg_dma_address(sg); } } ret = pl08x_prep_channel_resources(plchan, txd); if (ret) return NULL; return &txd->tx; } static int pl08x_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); struct pl08x_driver_data *pl08x = plchan->host; unsigned long flags; int ret = 0; /* Controls applicable to inactive channels */ if (cmd == DMA_SLAVE_CONFIG) { return dma_set_runtime_config(chan, (struct dma_slave_config *)arg); } /* * Anything succeeds on channels with no physical allocation and * no queued transfers. */ spin_lock_irqsave(&plchan->lock, flags); if (!plchan->phychan && !plchan->at) { spin_unlock_irqrestore(&plchan->lock, flags); return 0; } switch (cmd) { case DMA_TERMINATE_ALL: plchan->state = PL08X_CHAN_IDLE; if (plchan->phychan) { pl08x_terminate_phy_chan(pl08x, plchan->phychan); /* * Mark physical channel as free and free any slave * signal */ release_phy_channel(plchan); plchan->phychan_hold = 0; } /* Dequeue jobs and free LLIs */ if (plchan->at) { pl08x_free_txd(pl08x, plchan->at); plchan->at = NULL; } /* Dequeue jobs not yet fired as well */ pl08x_free_txd_list(pl08x, plchan); break; case DMA_PAUSE: pl08x_pause_phy_chan(plchan->phychan); plchan->state = PL08X_CHAN_PAUSED; break; case DMA_RESUME: pl08x_resume_phy_chan(plchan->phychan); plchan->state = PL08X_CHAN_RUNNING; break; default: /* Unknown command */ ret = -ENXIO; break; } spin_unlock_irqrestore(&plchan->lock, flags); return ret; } bool pl08x_filter_id(struct dma_chan *chan, void *chan_id) { struct pl08x_dma_chan *plchan; char *name = chan_id; /* Reject channels for devices not bound to this driver */ if (chan->device->dev->driver != &pl08x_amba_driver.drv) return false; plchan = to_pl08x_chan(chan); /* Check that the channel is not taken! */ if (!strcmp(plchan->name, name)) return true; return false; } /* * Just check that the device is there and active * TODO: turn this bit on/off depending on the number of physical channels * actually used, if it is zero... well shut it off. That will save some * power. Cut the clock at the same time. */ static void pl08x_ensure_on(struct pl08x_driver_data *pl08x) { /* The Nomadik variant does not have the config register */ if (pl08x->vd->nomadik) return; writel(PL080_CONFIG_ENABLE, pl08x->base + PL080_CONFIG); } static void pl08x_unmap_buffers(struct pl08x_txd *txd) { struct device *dev = txd->tx.chan->device->dev; struct pl08x_sg *dsg; if (!(txd->tx.flags & DMA_COMPL_SKIP_SRC_UNMAP)) { if (txd->tx.flags & DMA_COMPL_SRC_UNMAP_SINGLE) list_for_each_entry(dsg, &txd->dsg_list, node) dma_unmap_single(dev, dsg->src_addr, dsg->len, DMA_TO_DEVICE); else { list_for_each_entry(dsg, &txd->dsg_list, node) dma_unmap_page(dev, dsg->src_addr, dsg->len, DMA_TO_DEVICE); } } if (!(txd->tx.flags & DMA_COMPL_SKIP_DEST_UNMAP)) { if (txd->tx.flags & DMA_COMPL_DEST_UNMAP_SINGLE) list_for_each_entry(dsg, &txd->dsg_list, node) dma_unmap_single(dev, dsg->dst_addr, dsg->len, DMA_FROM_DEVICE); else list_for_each_entry(dsg, &txd->dsg_list, node) dma_unmap_page(dev, dsg->dst_addr, dsg->len, DMA_FROM_DEVICE); } } static void pl08x_tasklet(unsigned long data) { struct pl08x_dma_chan *plchan = (struct pl08x_dma_chan *) data; struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_txd *txd; unsigned long flags; spin_lock_irqsave(&plchan->lock, flags); txd = plchan->at; plchan->at = NULL; if (txd) { /* Update last completed */ dma_cookie_complete(&txd->tx); } /* If a new descriptor is queued, set it up plchan->at is NULL here */ if (!list_empty(&plchan->pend_list)) { struct pl08x_txd *next; next = list_first_entry(&plchan->pend_list, struct pl08x_txd, node); list_del(&next->node); pl08x_start_txd(plchan, next); } else if (plchan->phychan_hold) { /* * This channel is still in use - we have a new txd being * prepared and will soon be queued. Don't give up the * physical channel. */ } else { struct pl08x_dma_chan *waiting = NULL; /* * No more jobs, so free up the physical channel * Free any allocated signal on slave transfers too */ release_phy_channel(plchan); plchan->state = PL08X_CHAN_IDLE; /* * And NOW before anyone else can grab that free:d up * physical channel, see if there is some memcpy pending * that seriously needs to start because of being stacked * up while we were choking the physical channels with data. */ list_for_each_entry(waiting, &pl08x->memcpy.channels, chan.device_node) { if (waiting->state == PL08X_CHAN_WAITING && waiting->waiting != NULL) { int ret; /* This should REALLY not fail now */ ret = prep_phy_channel(waiting, waiting->waiting); BUG_ON(ret); waiting->phychan_hold--; waiting->state = PL08X_CHAN_RUNNING; waiting->waiting = NULL; pl08x_issue_pending(&waiting->chan); break; } } } spin_unlock_irqrestore(&plchan->lock, flags); if (txd) { dma_async_tx_callback callback = txd->tx.callback; void *callback_param = txd->tx.callback_param; /* Don't try to unmap buffers on slave channels */ if (!plchan->slave) pl08x_unmap_buffers(txd); /* Free the descriptor */ spin_lock_irqsave(&plchan->lock, flags); pl08x_free_txd(pl08x, txd); spin_unlock_irqrestore(&plchan->lock, flags); /* Callback to signal completion */ if (callback) callback(callback_param); } } static irqreturn_t pl08x_irq(int irq, void *dev) { struct pl08x_driver_data *pl08x = dev; u32 mask = 0, err, tc, i; /* check & clear - ERR & TC interrupts */ err = readl(pl08x->base + PL080_ERR_STATUS); if (err) { dev_err(&pl08x->adev->dev, "%s error interrupt, register value 0x%08x\n", __func__, err); writel(err, pl08x->base + PL080_ERR_CLEAR); } tc = readl(pl08x->base + PL080_TC_STATUS); if (tc) writel(tc, pl08x->base + PL080_TC_CLEAR); if (!err && !tc) return IRQ_NONE; for (i = 0; i < pl08x->vd->channels; i++) { if (((1 << i) & err) || ((1 << i) & tc)) { /* Locate physical channel */ struct pl08x_phy_chan *phychan = &pl08x->phy_chans[i]; struct pl08x_dma_chan *plchan = phychan->serving; if (!plchan) { dev_err(&pl08x->adev->dev, "%s Error TC interrupt on unused channel: 0x%08x\n", __func__, i); continue; } /* Schedule tasklet on this channel */ tasklet_schedule(&plchan->tasklet); mask |= (1 << i); } } return mask ? IRQ_HANDLED : IRQ_NONE; } static void pl08x_dma_slave_init(struct pl08x_dma_chan *chan) { u32 cctl = pl08x_cctl(chan->cd->cctl); chan->slave = true; chan->name = chan->cd->bus_id; chan->src_addr = chan->cd->addr; chan->dst_addr = chan->cd->addr; chan->src_cctl = cctl | PL080_CONTROL_DST_INCR | pl08x_select_bus(chan->cd->periph_buses, chan->host->mem_buses); chan->dst_cctl = cctl | PL080_CONTROL_SRC_INCR | pl08x_select_bus(chan->host->mem_buses, chan->cd->periph_buses); } /* * Initialise the DMAC memcpy/slave channels. * Make a local wrapper to hold required data */ static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x, struct dma_device *dmadev, unsigned int channels, bool slave) { struct pl08x_dma_chan *chan; int i; INIT_LIST_HEAD(&dmadev->channels); /* * Register as many many memcpy as we have physical channels, * we won't always be able to use all but the code will have * to cope with that situation. */ for (i = 0; i < channels; i++) { chan = kzalloc(sizeof(*chan), GFP_KERNEL); if (!chan) { dev_err(&pl08x->adev->dev, "%s no memory for channel\n", __func__); return -ENOMEM; } chan->host = pl08x; chan->state = PL08X_CHAN_IDLE; if (slave) { chan->cd = &pl08x->pd->slave_channels[i]; pl08x_dma_slave_init(chan); } else { chan->cd = &pl08x->pd->memcpy_channel; chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i); if (!chan->name) { kfree(chan); return -ENOMEM; } } dev_dbg(&pl08x->adev->dev, "initialize virtual channel \"%s\"\n", chan->name); chan->chan.device = dmadev; dma_cookie_init(&chan->chan); spin_lock_init(&chan->lock); INIT_LIST_HEAD(&chan->pend_list); tasklet_init(&chan->tasklet, pl08x_tasklet, (unsigned long) chan); list_add_tail(&chan->chan.device_node, &dmadev->channels); } dev_info(&pl08x->adev->dev, "initialized %d virtual %s channels\n", i, slave ? "slave" : "memcpy"); return i; } static void pl08x_free_virtual_channels(struct dma_device *dmadev) { struct pl08x_dma_chan *chan = NULL; struct pl08x_dma_chan *next; list_for_each_entry_safe(chan, next, &dmadev->channels, chan.device_node) { list_del(&chan->chan.device_node); kfree(chan); } } #ifdef CONFIG_DEBUG_FS static const char *pl08x_state_str(enum pl08x_dma_chan_state state) { switch (state) { case PL08X_CHAN_IDLE: return "idle"; case PL08X_CHAN_RUNNING: return "running"; case PL08X_CHAN_PAUSED: return "paused"; case PL08X_CHAN_WAITING: return "waiting"; default: break; } return "UNKNOWN STATE"; } static int pl08x_debugfs_show(struct seq_file *s, void *data) { struct pl08x_driver_data *pl08x = s->private; struct pl08x_dma_chan *chan; struct pl08x_phy_chan *ch; unsigned long flags; int i; seq_printf(s, "PL08x physical channels:\n"); seq_printf(s, "CHANNEL:\tUSER:\n"); seq_printf(s, "--------\t-----\n"); for (i = 0; i < pl08x->vd->channels; i++) { struct pl08x_dma_chan *virt_chan; ch = &pl08x->phy_chans[i]; spin_lock_irqsave(&ch->lock, flags); virt_chan = ch->serving; seq_printf(s, "%d\t\t%s%s\n", ch->id, virt_chan ? virt_chan->name : "(none)", ch->locked ? " LOCKED" : ""); spin_unlock_irqrestore(&ch->lock, flags); } seq_printf(s, "\nPL08x virtual memcpy channels:\n"); seq_printf(s, "CHANNEL:\tSTATE:\n"); seq_printf(s, "--------\t------\n"); list_for_each_entry(chan, &pl08x->memcpy.channels, chan.device_node) { seq_printf(s, "%s\t\t%s\n", chan->name, pl08x_state_str(chan->state)); } seq_printf(s, "\nPL08x virtual slave channels:\n"); seq_printf(s, "CHANNEL:\tSTATE:\n"); seq_printf(s, "--------\t------\n"); list_for_each_entry(chan, &pl08x->slave.channels, chan.device_node) { seq_printf(s, "%s\t\t%s\n", chan->name, pl08x_state_str(chan->state)); } return 0; } static int pl08x_debugfs_open(struct inode *inode, struct file *file) { return single_open(file, pl08x_debugfs_show, inode->i_private); } static const struct file_operations pl08x_debugfs_operations = { .open = pl08x_debugfs_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static void init_pl08x_debugfs(struct pl08x_driver_data *pl08x) { /* Expose a simple debugfs interface to view all clocks */ (void) debugfs_create_file(dev_name(&pl08x->adev->dev), S_IFREG | S_IRUGO, NULL, pl08x, &pl08x_debugfs_operations); } #else static inline void init_pl08x_debugfs(struct pl08x_driver_data *pl08x) { } #endif static int pl08x_probe(struct amba_device *adev, const struct amba_id *id) { struct pl08x_driver_data *pl08x; const struct vendor_data *vd = id->data; int ret = 0; int i; ret = amba_request_regions(adev, NULL); if (ret) return ret; /* Create the driver state holder */ pl08x = kzalloc(sizeof(*pl08x), GFP_KERNEL); if (!pl08x) { ret = -ENOMEM; goto out_no_pl08x; } /* Initialize memcpy engine */ dma_cap_set(DMA_MEMCPY, pl08x->memcpy.cap_mask); pl08x->memcpy.dev = &adev->dev; pl08x->memcpy.device_alloc_chan_resources = pl08x_alloc_chan_resources; pl08x->memcpy.device_free_chan_resources = pl08x_free_chan_resources; pl08x->memcpy.device_prep_dma_memcpy = pl08x_prep_dma_memcpy; pl08x->memcpy.device_prep_dma_interrupt = pl08x_prep_dma_interrupt; pl08x->memcpy.device_tx_status = pl08x_dma_tx_status; pl08x->memcpy.device_issue_pending = pl08x_issue_pending; pl08x->memcpy.device_control = pl08x_control; /* Initialize slave engine */ dma_cap_set(DMA_SLAVE, pl08x->slave.cap_mask); pl08x->slave.dev = &adev->dev; pl08x->slave.device_alloc_chan_resources = pl08x_alloc_chan_resources; pl08x->slave.device_free_chan_resources = pl08x_free_chan_resources; pl08x->slave.device_prep_dma_interrupt = pl08x_prep_dma_interrupt; pl08x->slave.device_tx_status = pl08x_dma_tx_status; pl08x->slave.device_issue_pending = pl08x_issue_pending; pl08x->slave.device_prep_slave_sg = pl08x_prep_slave_sg; pl08x->slave.device_control = pl08x_control; /* Get the platform data */ pl08x->pd = dev_get_platdata(&adev->dev); if (!pl08x->pd) { dev_err(&adev->dev, "no platform data supplied\n"); goto out_no_platdata; } /* Assign useful pointers to the driver state */ pl08x->adev = adev; pl08x->vd = vd; /* By default, AHB1 only. If dualmaster, from platform */ pl08x->lli_buses = PL08X_AHB1; pl08x->mem_buses = PL08X_AHB1; if (pl08x->vd->dualmaster) { pl08x->lli_buses = pl08x->pd->lli_buses; pl08x->mem_buses = pl08x->pd->mem_buses; } /* A DMA memory pool for LLIs, align on 1-byte boundary */ pl08x->pool = dma_pool_create(DRIVER_NAME, &pl08x->adev->dev, PL08X_LLI_TSFR_SIZE, PL08X_ALIGN, 0); if (!pl08x->pool) { ret = -ENOMEM; goto out_no_lli_pool; } pl08x->base = ioremap(adev->res.start, resource_size(&adev->res)); if (!pl08x->base) { ret = -ENOMEM; goto out_no_ioremap; } /* Turn on the PL08x */ pl08x_ensure_on(pl08x); /* Attach the interrupt handler */ writel(0x000000FF, pl08x->base + PL080_ERR_CLEAR); writel(0x000000FF, pl08x->base + PL080_TC_CLEAR); ret = request_irq(adev->irq[0], pl08x_irq, IRQF_DISABLED, DRIVER_NAME, pl08x); if (ret) { dev_err(&adev->dev, "%s failed to request interrupt %d\n", __func__, adev->irq[0]); goto out_no_irq; } /* Initialize physical channels */ pl08x->phy_chans = kzalloc((vd->channels * sizeof(*pl08x->phy_chans)), GFP_KERNEL); if (!pl08x->phy_chans) { dev_err(&adev->dev, "%s failed to allocate " "physical channel holders\n", __func__); goto out_no_phychans; } for (i = 0; i < vd->channels; i++) { struct pl08x_phy_chan *ch = &pl08x->phy_chans[i]; ch->id = i; ch->base = pl08x->base + PL080_Cx_BASE(i); spin_lock_init(&ch->lock); ch->signal = -1; /* * Nomadik variants can have channels that are locked * down for the secure world only. Lock up these channels * by perpetually serving a dummy virtual channel. */ if (vd->nomadik) { u32 val; val = readl(ch->base + PL080_CH_CONFIG); if (val & (PL080N_CONFIG_ITPROT | PL080N_CONFIG_SECPROT)) { dev_info(&adev->dev, "physical channel %d reserved for secure access only\n", i); ch->locked = true; } } dev_dbg(&adev->dev, "physical channel %d is %s\n", i, pl08x_phy_channel_busy(ch) ? "BUSY" : "FREE"); } /* Register as many memcpy channels as there are physical channels */ ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->memcpy, pl08x->vd->channels, false); if (ret <= 0) { dev_warn(&pl08x->adev->dev, "%s failed to enumerate memcpy channels - %d\n", __func__, ret); goto out_no_memcpy; } pl08x->memcpy.chancnt = ret; /* Register slave channels */ ret = pl08x_dma_init_virtual_channels(pl08x, &pl08x->slave, pl08x->pd->num_slave_channels, true); if (ret <= 0) { dev_warn(&pl08x->adev->dev, "%s failed to enumerate slave channels - %d\n", __func__, ret); goto out_no_slave; } pl08x->slave.chancnt = ret; ret = dma_async_device_register(&pl08x->memcpy); if (ret) { dev_warn(&pl08x->adev->dev, "%s failed to register memcpy as an async device - %d\n", __func__, ret); goto out_no_memcpy_reg; } ret = dma_async_device_register(&pl08x->slave); if (ret) { dev_warn(&pl08x->adev->dev, "%s failed to register slave as an async device - %d\n", __func__, ret); goto out_no_slave_reg; } amba_set_drvdata(adev, pl08x); init_pl08x_debugfs(pl08x); dev_info(&pl08x->adev->dev, "DMA: PL%03x rev%u at 0x%08llx irq %d\n", amba_part(adev), amba_rev(adev), (unsigned long long)adev->res.start, adev->irq[0]); return 0; out_no_slave_reg: dma_async_device_unregister(&pl08x->memcpy); out_no_memcpy_reg: pl08x_free_virtual_channels(&pl08x->slave); out_no_slave: pl08x_free_virtual_channels(&pl08x->memcpy); out_no_memcpy: kfree(pl08x->phy_chans); out_no_phychans: free_irq(adev->irq[0], pl08x); out_no_irq: iounmap(pl08x->base); out_no_ioremap: dma_pool_destroy(pl08x->pool); out_no_lli_pool: out_no_platdata: kfree(pl08x); out_no_pl08x: amba_release_regions(adev); return ret; } /* PL080 has 8 channels and the PL080 have just 2 */ static struct vendor_data vendor_pl080 = { .channels = 8, .dualmaster = true, }; static struct vendor_data vendor_nomadik = { .channels = 8, .dualmaster = true, .nomadik = true, }; static struct vendor_data vendor_pl081 = { .channels = 2, .dualmaster = false, }; static struct amba_id pl08x_ids[] = { /* PL080 */ { .id = 0x00041080, .mask = 0x000fffff, .data = &vendor_pl080, }, /* PL081 */ { .id = 0x00041081, .mask = 0x000fffff, .data = &vendor_pl081, }, /* Nomadik 8815 PL080 variant */ { .id = 0x00280080, .mask = 0x00ffffff, .data = &vendor_nomadik, }, { 0, 0 }, }; MODULE_DEVICE_TABLE(amba, pl08x_ids); static struct amba_driver pl08x_amba_driver = { .drv.name = DRIVER_NAME, .id_table = pl08x_ids, .probe = pl08x_probe, }; static int __init pl08x_init(void) { int retval; retval = amba_driver_register(&pl08x_amba_driver); if (retval) printk(KERN_WARNING DRIVER_NAME "failed to register as an AMBA device (%d)\n", retval); return retval; } subsys_initcall(pl08x_init);