/* * Copyright (c) 2006 ARM Ltd. * Copyright (c) 2010 ST-Ericsson SA * * Author: Peter Pearse <peter.pearse@arm.com> * Author: Linus Walleij <linus.walleij@stericsson.com> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * * 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. * * Only the former works sanely with scatter lists, so we only implement * the DMAC flow control method. However, peripherals which use the LBREQ * and LSREQ signals (eg, MMCI) are unable to use this mode, which through * these hardware restrictions prevents them from using scatter DMA. * * Global TODO: * - Break out common code from arch/arm/mach-s3c64xx and share */ #include <linux/device.h> #include <linux/init.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/slab.h> #include <linux/delay.h> #include <linux/dmapool.h> #include <linux/dmaengine.h> #include <linux/amba/bus.h> #include <linux/amba/pl08x.h> #include <linux/debugfs.h> #include <linux/seq_file.h> #include <asm/hardware/pl080.h> #define DRIVER_NAME "pl08xdmac" /** * 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. */ struct vendor_data { u8 channels; bool dualmaster; }; /* * 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_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; spinlock_t lock; }; /* * PL08X specific defines */ /* * Memory boundaries: the manual for PL08x says that the controller * cannot read past a 1KiB boundary, so these defines are used to * create transfer LLIs that do not cross such boundaries. */ #define PL08X_BOUNDARY_SHIFT (10) /* 1KB 0x400 */ #define PL08X_BOUNDARY_SIZE (1 << PL08X_BOUNDARY_SHIFT) /* Minimum period between work queue runs */ #define PL08X_WQ_PERIODMIN 20 /* 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 PL08X_MAX_ALLOCS 0x40 #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) { bytes += txdi->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->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_driver_data *pl08x; struct pl08x_bus_data srcbus; struct pl08x_bus_data dstbus; size_t remainder; }; /* * Autoselect a master bus to use for the transfer this prefers the * destination bus if both available if fixed address on one bus the * other will be chosen */ 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->srcbus; *sbus = &bd->dstbus; } else if (!(cctl & PL080_CONTROL_SRC_INCR)) { *mbus = &bd->dstbus; *sbus = &bd->srcbus; } else { if (bd->dstbus.buswidth == 4) { *mbus = &bd->dstbus; *sbus = &bd->srcbus; } else if (bd->srcbus.buswidth == 4) { *mbus = &bd->srcbus; *sbus = &bd->dstbus; } else if (bd->dstbus.buswidth == 2) { *mbus = &bd->dstbus; *sbus = &bd->srcbus; } else if (bd->srcbus.buswidth == 2) { *mbus = &bd->srcbus; *sbus = &bd->dstbus; } else { /* bd->srcbus.buswidth == 1 */ *mbus = &bd->dstbus; *sbus = &bd->srcbus; } } } /* * 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); if (bd->pl08x->lli_buses & PL08X_AHB2) llis_va[num_llis].lli |= PL080_LLI_LM_AHB2; 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; } /* * Return number of bytes to fill to boundary, or len. * This calculation works for any value of addr. */ static inline size_t pl08x_pre_boundary(u32 addr, size_t len) { size_t boundary_len = PL08X_BOUNDARY_SIZE - (addr & (PL08X_BOUNDARY_SIZE - 1)); return min(boundary_len, 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; size_t max_bytes_per_lli; size_t total_bytes = 0; struct pl08x_lli *llis_va; 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++; /* Get the default CCTL */ cctl = txd->cctl; bd.txd = txd; bd.pl08x = pl08x; bd.srcbus.addr = txd->src_addr; bd.dstbus.addr = txd->dst_addr; /* 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); /* Set up the bus widths to the maximum */ bd.srcbus.buswidth = bd.srcbus.maxwidth; bd.dstbus.buswidth = bd.dstbus.maxwidth; dev_vdbg(&pl08x->adev->dev, "%s source bus is %d bytes wide, dest bus is %d bytes wide\n", __func__, bd.srcbus.buswidth, bd.dstbus.buswidth); /* * Bytes transferred == tsize * MIN(buswidths), not max(buswidths) */ max_bytes_per_lli = min(bd.srcbus.buswidth, bd.dstbus.buswidth) * PL080_CONTROL_TRANSFER_SIZE_MASK; dev_vdbg(&pl08x->adev->dev, "%s max bytes per lli = %zu\n", __func__, max_bytes_per_lli); /* We need to count this down to zero */ bd.remainder = txd->len; dev_vdbg(&pl08x->adev->dev, "%s remainder = %zu\n", __func__, bd.remainder); /* * Choose bus to align to * - prefers destination bus if both available * - if fixed address on one bus chooses other */ pl08x_choose_master_bus(&bd, &mbus, &sbus, cctl); if (txd->len < mbus->buswidth) { /* Less than a bus width available - send as single bytes */ while (bd.remainder) { dev_vdbg(&pl08x->adev->dev, "%s single byte LLIs for a transfer of " "less than a bus width (remain 0x%08x)\n", __func__, bd.remainder); cctl = pl08x_cctl_bits(cctl, 1, 1, 1); pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); total_bytes++; } } else { /* Make one byte LLIs until master bus is aligned */ while ((mbus->addr) % (mbus->buswidth)) { dev_vdbg(&pl08x->adev->dev, "%s adjustment lli for less than bus width " "(remain 0x%08x)\n", __func__, bd.remainder); cctl = pl08x_cctl_bits(cctl, 1, 1, 1); pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); total_bytes++; } /* * 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; } /* * Make largest possible LLIs until less than one bus * width left */ while (bd.remainder > (mbus->buswidth - 1)) { size_t lli_len, target_len, tsize, odd_bytes; /* * If enough left try to send max possible, * otherwise try to send the remainder */ target_len = min(bd.remainder, max_bytes_per_lli); /* * Set bus lengths for incrementing buses to the * number of bytes which fill to next memory boundary, * limiting on the target length calculated above. */ if (cctl & PL080_CONTROL_SRC_INCR) bd.srcbus.fill_bytes = pl08x_pre_boundary(bd.srcbus.addr, target_len); else bd.srcbus.fill_bytes = target_len; if (cctl & PL080_CONTROL_DST_INCR) bd.dstbus.fill_bytes = pl08x_pre_boundary(bd.dstbus.addr, target_len); else bd.dstbus.fill_bytes = target_len; /* Find the nearest */ lli_len = min(bd.srcbus.fill_bytes, bd.dstbus.fill_bytes); BUG_ON(lli_len > bd.remainder); if (lli_len <= 0) { dev_err(&pl08x->adev->dev, "%s lli_len is %zu, <= 0\n", __func__, lli_len); return 0; } if (lli_len == target_len) { /* * Can send what we wanted. * Maintain alignment */ lli_len = (lli_len/mbus->buswidth) * mbus->buswidth; odd_bytes = 0; } else { /* * So now we know how many bytes to transfer * to get to the nearest boundary. The next * LLI will past the boundary. However, we * may be working to a boundary on the slave * bus. We need to ensure the master stays * aligned, and that we are working in * multiples of the bus widths. */ odd_bytes = lli_len % mbus->buswidth; lli_len -= odd_bytes; } if (lli_len) { /* * Check against minimum bus alignment: * Calculate actual transfer size in relation * to bus width an get a maximum remainder of * the smallest bus width - 1 */ /* FIXME: use round_down()? */ tsize = lli_len / min(mbus->buswidth, sbus->buswidth); lli_len = tsize * min(mbus->buswidth, sbus->buswidth); if (target_len != lli_len) { dev_vdbg(&pl08x->adev->dev, "%s can't send what we want. Desired 0x%08zx, lli of 0x%08zx bytes in txd of 0x%08zx\n", __func__, target_len, lli_len, txd->len); } cctl = pl08x_cctl_bits(cctl, bd.srcbus.buswidth, bd.dstbus.buswidth, tsize); 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); pl08x_fill_lli_for_desc(&bd, num_llis++, lli_len, cctl); total_bytes += lli_len; } if (odd_bytes) { /* * Creep past the boundary, maintaining * master alignment */ int j; for (j = 0; (j < mbus->buswidth) && (bd.remainder); j++) { cctl = pl08x_cctl_bits(cctl, 1, 1, 1); dev_vdbg(&pl08x->adev->dev, "%s align with boundary, single byte (remain 0x%08zx)\n", __func__, bd.remainder); pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); total_bytes++; } } } /* * Send any odd bytes */ while (bd.remainder) { cctl = pl08x_cctl_bits(cctl, 1, 1, 1); dev_vdbg(&pl08x->adev->dev, "%s align with boundary, single odd byte (remain %zu)\n", __func__, bd.remainder); pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); total_bytes++; } } if (total_bytes != txd->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, txd->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; for (i = 0; i < num_llis; i++) { dev_vdbg(&pl08x->adev->dev, "lli %d @%p: csrc=0x%08x, cdst=0x%08x, cctl=0x%08x, clli=0x%08x\n", i, &llis_va[i], llis_va[i].src, llis_va[i].dst, llis_va[i].cctl, llis_va[i].lli ); } } #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) { /* Free the LLI */ dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus); pl08x->pool_ctr--; 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) return 0; 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 && ch->signal < 0 && pl08x->pd->get_signal) { ret = pl08x->pd->get_signal(plchan); 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; /* Assign the flow control signal to this channel */ if (txd->direction == DMA_TO_DEVICE) txd->ccfg |= ch->signal << PL080_CONFIG_DST_SEL_SHIFT; else if (txd->direction == DMA_FROM_DEVICE) txd->ccfg |= ch->signal << PL080_CONFIG_SRC_SEL_SHIFT; } dev_dbg(&pl08x->adev->dev, "allocated physical channel %d and signal %d for xfer on %s\n", ch->id, ch->signal, plchan->name); plchan->phychan_hold++; plchan->phychan = ch; 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); 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; spin_lock_irqsave(&plchan->lock, flags); plchan->chan.cookie += 1; if (plchan->chan.cookie < 0) plchan->chan.cookie = 1; tx->cookie = plchan->chan.cookie; /* 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 tx->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); dma_cookie_t last_used; dma_cookie_t last_complete; enum dma_status ret; u32 bytesleft = 0; last_used = plchan->chan.cookie; last_complete = plchan->lc; ret = dma_async_is_complete(cookie, last_complete, last_used); if (ret == DMA_SUCCESS) { dma_set_tx_state(txstate, last_complete, last_used, 0); return ret; } /* * This cookie not complete yet */ last_used = plchan->chan.cookie; last_complete = plchan->lc; /* Get number of bytes left in the active transactions and queue */ bytesleft = pl08x_getbytes_chan(plchan); dma_set_tx_state(txstate, last_complete, last_used, bytesleft); 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 { int burstwords; u32 reg; }; static const struct burst_table burst_sizes[] = { { .burstwords = 256, .reg = (PL080_BSIZE_256 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_256 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 128, .reg = (PL080_BSIZE_128 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_128 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 64, .reg = (PL080_BSIZE_64 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_64 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 32, .reg = (PL080_BSIZE_32 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_32 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 16, .reg = (PL080_BSIZE_16 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_16 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 8, .reg = (PL080_BSIZE_8 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_8 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 4, .reg = (PL080_BSIZE_4 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_4 << PL080_CONTROL_DB_SIZE_SHIFT), }, { .burstwords = 1, .reg = (PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT), }, }; 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; struct pl08x_channel_data *cd = plchan->cd; enum dma_slave_buswidth addr_width; dma_addr_t addr; u32 maxburst; u32 cctl = 0; int i; if (!plchan->slave) return -EINVAL; /* Transfer direction */ plchan->runtime_direction = config->direction; if (config->direction == DMA_TO_DEVICE) { addr = config->dst_addr; addr_width = config->dst_addr_width; maxburst = config->dst_maxburst; } else if (config->direction == DMA_FROM_DEVICE) { addr = config->src_addr; 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; } switch (addr_width) { case DMA_SLAVE_BUSWIDTH_1_BYTE: cctl |= (PL080_WIDTH_8BIT << PL080_CONTROL_SWIDTH_SHIFT) | (PL080_WIDTH_8BIT << PL080_CONTROL_DWIDTH_SHIFT); break; case DMA_SLAVE_BUSWIDTH_2_BYTES: cctl |= (PL080_WIDTH_16BIT << PL080_CONTROL_SWIDTH_SHIFT) | (PL080_WIDTH_16BIT << PL080_CONTROL_DWIDTH_SHIFT); break; case DMA_SLAVE_BUSWIDTH_4_BYTES: cctl |= (PL080_WIDTH_32BIT << PL080_CONTROL_SWIDTH_SHIFT) | (PL080_WIDTH_32BIT << PL080_CONTROL_DWIDTH_SHIFT); break; default: dev_err(&pl08x->adev->dev, "bad runtime_config: alien address width\n"); return -EINVAL; } /* * Now decide on a maxburst: * 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 == 0) { cctl |= (PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT) | (PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT); } else { for (i = 0; i < ARRAY_SIZE(burst_sizes); i++) if (burst_sizes[i].burstwords <= maxburst) break; cctl |= burst_sizes[i].reg; } plchan->runtime_addr = addr; /* Modify the default channel data to fit PrimeCell request */ cd->cctl = cctl; 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_FROM_DEVICE) ? "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) { kfree(txd); 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; } /* * 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(struct pl08x_driver_data *pl08x, 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 struct pl08x_txd *pl08x_get_txd(struct pl08x_dma_chan *plchan, unsigned long flags) { struct pl08x_txd *txd = kzalloc(sizeof(struct pl08x_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); /* 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; int ret; txd = pl08x_get_txd(plchan, flags); if (!txd) { dev_err(&pl08x->adev->dev, "%s no memory for descriptor\n", __func__); return NULL; } txd->direction = DMA_NONE; txd->src_addr = src; txd->dst_addr = dest; txd->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, 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_data_direction direction, unsigned long flags) { struct pl08x_dma_chan *plchan = to_pl08x_chan(chan); struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_txd *txd; u8 src_buses, dst_buses; int ret; /* * Current implementation ASSUMES only one sg */ if (sg_len != 1) { dev_err(&pl08x->adev->dev, "%s prepared too long sglist\n", __func__); BUG(); } dev_dbg(&pl08x->adev->dev, "%s prepare transaction of %d bytes from %s\n", __func__, sgl->length, 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; txd->len = sgl->length; txd->cctl = plchan->cd->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 */ txd->cctl |= PL080_CONTROL_PROT_SYS; if (direction == DMA_TO_DEVICE) { txd->ccfg |= PL080_FLOW_MEM2PER << PL080_CONFIG_FLOW_CONTROL_SHIFT; txd->cctl |= PL080_CONTROL_SRC_INCR; txd->src_addr = sgl->dma_address; if (plchan->runtime_addr) txd->dst_addr = plchan->runtime_addr; else txd->dst_addr = plchan->cd->addr; src_buses = pl08x->mem_buses; dst_buses = plchan->cd->periph_buses; } else if (direction == DMA_FROM_DEVICE) { txd->ccfg |= PL080_FLOW_PER2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT; txd->cctl |= PL080_CONTROL_DST_INCR; if (plchan->runtime_addr) txd->src_addr = plchan->runtime_addr; else txd->src_addr = plchan->cd->addr; txd->dst_addr = sgl->dma_address; src_buses = plchan->cd->periph_buses; dst_buses = pl08x->mem_buses; } else { dev_err(&pl08x->adev->dev, "%s direction unsupported\n", __func__); return NULL; } txd->cctl |= pl08x_select_bus(pl08x, src_buses, dst_buses); 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); } /* 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 = to_pl08x_chan(chan); char *name = chan_id; /* 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) { u32 val; val = readl(pl08x->base + PL080_CONFIG); val &= ~(PL080_CONFIG_M2_BE | PL080_CONFIG_M1_BE | PL080_CONFIG_ENABLE); /* We implicitly clear bit 1 and that means little-endian mode */ val |= PL080_CONFIG_ENABLE; writel(val, pl08x->base + PL080_CONFIG); } static void pl08x_unmap_buffers(struct pl08x_txd *txd) { struct device *dev = txd->tx.chan->device->dev; if (!(txd->tx.flags & DMA_COMPL_SKIP_SRC_UNMAP)) { if (txd->tx.flags & DMA_COMPL_SRC_UNMAP_SINGLE) dma_unmap_single(dev, txd->src_addr, txd->len, DMA_TO_DEVICE); else dma_unmap_page(dev, txd->src_addr, txd->len, DMA_TO_DEVICE); } if (!(txd->tx.flags & DMA_COMPL_SKIP_DEST_UNMAP)) { if (txd->tx.flags & DMA_COMPL_DEST_UNMAP_SINGLE) dma_unmap_single(dev, txd->dst_addr, txd->len, DMA_FROM_DEVICE); else dma_unmap_page(dev, txd->dst_addr, txd->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 */ plchan->lc = txd->tx.cookie; } /* 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; u32 val; int i; val = readl(pl08x->base + PL080_ERR_STATUS); if (val) { /* An error interrupt (on one or more channels) */ dev_err(&pl08x->adev->dev, "%s error interrupt, register value 0x%08x\n", __func__, val); /* * Simply clear ALL PL08X error interrupts, * regardless of channel and cause * FIXME: should be 0x00000003 on PL081 really. */ writel(0x000000FF, pl08x->base + PL080_ERR_CLEAR); } val = readl(pl08x->base + PL080_INT_STATUS); for (i = 0; i < pl08x->vd->channels; i++) { if ((1 << i) & val) { /* Locate physical channel */ struct pl08x_phy_chan *phychan = &pl08x->phy_chans[i]; struct pl08x_dma_chan *plchan = phychan->serving; /* Schedule tasklet on this channel */ tasklet_schedule(&plchan->tasklet); mask |= (1 << i); } } /* Clear only the terminal interrupts on channels we processed */ writel(mask, pl08x->base + PL080_TC_CLEAR); return mask ? IRQ_HANDLED : IRQ_NONE; } /* * 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(struct pl08x_dma_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->slave = true; chan->name = pl08x->pd->slave_channels[i].bus_id; chan->cd = &pl08x->pd->slave_channels[i]; } else { chan->cd = &pl08x->pd->memcpy_channel; chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i); if (!chan->name) { kfree(chan); return -ENOMEM; } } if (chan->cd->circular_buffer) { dev_err(&pl08x->adev->dev, "channel %s: circular buffers not supported\n", chan->name); kfree(chan); continue; } dev_info(&pl08x->adev->dev, "initialize virtual channel \"%s\"\n", chan->name); chan->chan.device = dmadev; chan->chan.cookie = 0; chan->lc = 0; 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\n", ch->id, virt_chan ? virt_chan->name : "(none)"); 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(struct pl08x_driver_data), 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; } spin_lock_init(&pl08x->lock); 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 = kmalloc((vd->channels * sizeof(struct pl08x_phy_chan)), 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->serving = NULL; ch->signal = -1; dev_info(&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_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 = 0x00280880, .mask = 0x00ffffff, .data = &vendor_pl080, }, { 0, 0 }, }; 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);