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Diffstat (limited to 'drivers/dma/amba-pl08x.c')
| -rw-r--r-- | drivers/dma/amba-pl08x.c | 2167 |
1 files changed, 2167 insertions, 0 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c new file mode 100644 index 000000000000..b605cc9ac3a2 --- /dev/null +++ b/drivers/dma/amba-pl08x.c @@ -0,0 +1,2167 @@ +/* + * 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 iin 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 + * + * Only DMAC flow control is implemented + * + * 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/pci.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/dmapool.h> +#include <linux/amba/bus.h> +#include <linux/dmaengine.h> +#include <linux/amba/pl08x.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +#include <asm/hardware/pl080.h> +#include <asm/dma.h> +#include <asm/mach/dma.h> +#include <asm/atomic.h> +#include <asm/processor.h> +#include <asm/cacheflush.h> + +#define DRIVER_NAME "pl08xdmac" + +/** + * struct vendor_data - vendor-specific config parameters + * for PL08x derivates + * @name: the name of this specific variant + * @channels: the number of channels available in this variant + * @dualmaster: whether this version supports dual AHB masters + * or not. + */ +struct vendor_data { + char *name; + 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 + */ +struct lli { + dma_addr_t src; + dma_addr_t dst; + dma_addr_t next; + 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 + * @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; + struct vendor_data *vd; + struct pl08x_platform_data *pd; + struct pl08x_phy_chan *phy_chans; + struct dma_pool *pool; + int pool_ctr; + 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 + +/* Maximimum 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 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); +} + +/* + * 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 + */ +static void pl08x_set_cregs(struct pl08x_driver_data *pl08x, + struct pl08x_phy_chan *ch) +{ + /* Wait for channel inactive */ + while (pl08x_phy_channel_busy(ch)) + ; + + dev_vdbg(&pl08x->adev->dev, + "WRITE channel %d: csrc=%08x, cdst=%08x, " + "cctl=%08x, clli=%08x, ccfg=%08x\n", + ch->id, + ch->csrc, + ch->cdst, + ch->cctl, + ch->clli, + ch->ccfg); + + writel(ch->csrc, ch->base + PL080_CH_SRC_ADDR); + writel(ch->cdst, ch->base + PL080_CH_DST_ADDR); + writel(ch->clli, ch->base + PL080_CH_LLI); + writel(ch->cctl, ch->base + PL080_CH_CONTROL); + writel(ch->ccfg, ch->base + PL080_CH_CONFIG); +} + +static inline void pl08x_config_phychan_for_txd(struct pl08x_dma_chan *plchan) +{ + struct pl08x_channel_data *cd = plchan->cd; + struct pl08x_phy_chan *phychan = plchan->phychan; + struct pl08x_txd *txd = plchan->at; + + /* Copy the basic control register calculated at transfer config */ + phychan->csrc = txd->csrc; + phychan->cdst = txd->cdst; + phychan->clli = txd->clli; + phychan->cctl = txd->cctl; + + /* Assign the signal to the proper control registers */ + phychan->ccfg = cd->ccfg; + phychan->ccfg &= ~PL080_CONFIG_SRC_SEL_MASK; + phychan->ccfg &= ~PL080_CONFIG_DST_SEL_MASK; + /* If it wasn't set from AMBA, ignore it */ + if (txd->direction == DMA_TO_DEVICE) + /* Select signal as destination */ + phychan->ccfg |= + (phychan->signal << PL080_CONFIG_DST_SEL_SHIFT); + else if (txd->direction == DMA_FROM_DEVICE) + /* Select signal as source */ + phychan->ccfg |= + (phychan->signal << PL080_CONFIG_SRC_SEL_SHIFT); + /* Always enable error interrupts */ + phychan->ccfg |= PL080_CONFIG_ERR_IRQ_MASK; + /* Always enable terminal interrupts */ + phychan->ccfg |= PL080_CONFIG_TC_IRQ_MASK; +} + +/* + * Enable the DMA channel + * Assumes all other configuration bits have been set + * as desired before this code is called + */ +static void pl08x_enable_phy_chan(struct pl08x_driver_data *pl08x, + struct pl08x_phy_chan *ch) +{ + u32 val; + + /* + * Do not access config register until channel shows as disabled + */ + while (readl(pl08x->base + PL080_EN_CHAN) & (1 << ch->id)) + ; + + /* + * Do not access config register until channel shows as inactive + */ + val = readl(ch->base + PL080_CH_CONFIG); + while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE)) + val = readl(ch->base + PL080_CH_CONFIG); + + writel(val | PL080_CONFIG_ENABLE, ch->base + PL080_CH_CONFIG); +} + +/* + * Overall DMAC remains enabled always. + * + * Disabling individual channels could lose data. + * + * Disable the peripheral DMA after disabling the DMAC + * in order to allow the DMAC FIFO to drain, and + * hence allow the channel to show inactive + * + */ +static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch) +{ + u32 val; + + /* 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 */ + while (pl08x_phy_channel_busy(ch)) + ; +} + +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); +} + + +/* Stops the channel */ +static void pl08x_stop_phy_chan(struct pl08x_phy_chan *ch) +{ + u32 val; + + pl08x_pause_phy_chan(ch); + + /* Disable channel */ + val = readl(ch->base + PL080_CH_CONFIG); + val &= ~PL080_CONFIG_ENABLE; + val &= ~PL080_CONFIG_ERR_IRQ_MASK; + val &= ~PL080_CONFIG_TC_IRQ_MASK; + writel(val, ch->base + PL080_CH_CONFIG); +} + +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 *txdi = NULL; + struct pl08x_txd *txd; + unsigned long flags; + u32 bytes = 0; + + spin_lock_irqsave(&plchan->lock, flags); + + ch = plchan->phychan; + txd = plchan->at; + + /* + * Next follow the LLIs to get the number of pending bytes in the + * currently active transaction. + */ + if (ch && txd) { + struct lli *llis_va = txd->llis_va; + struct lli *llis_bus = (struct lli *) txd->llis_bus; + u32 clli = readl(ch->base + PL080_CH_LLI); + + /* First get the bytes in the current active LLI */ + bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL)); + + if (clli) { + int i = 0; + + /* Forward to the LLI pointed to by clli */ + while ((clli != (u32) &(llis_bus[i])) && + (i < MAX_NUM_TSFR_LLIS)) + i++; + + while (clli) { + bytes += get_bytes_in_cctl(llis_va[i].cctl); + /* + * A clli of 0x00000000 will terminate the + * LLI list + */ + clli = llis_va[i].next; + i++; + } + } + } + + /* Sum up all queued transactions */ + if (!list_empty(&plchan->desc_list)) { + list_for_each_entry(txdi, &plchan->desc_list, node) { + bytes += txdi->len; + } + + } + + spin_unlock_irqrestore(&plchan->lock, flags); + + return bytes; +} + +/* + * Allocate a physical channel for a virtual channel + */ +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; + + /* + * 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. + */ + 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; + + /* Stop the channel and clear its interrupts */ + pl08x_stop_phy_chan(ch); + writel((1 << ch->id), pl08x->base + PL080_ERR_CLEAR); + writel((1 << ch->id), pl08x->base + PL080_TC_CLEAR); + + /* Mark it as free */ + spin_lock_irqsave(&ch->lock, flags); + 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, + u32 tsize) +{ + u32 retbits = cctl; + + /* Remove all src, dst and transfersize 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; +} + +/* + * 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 + */ +void pl08x_choose_master_bus(struct pl08x_bus_data *src_bus, + struct pl08x_bus_data *dst_bus, struct pl08x_bus_data **mbus, + struct pl08x_bus_data **sbus, u32 cctl) +{ + if (!(cctl & PL080_CONTROL_DST_INCR)) { + *mbus = src_bus; + *sbus = dst_bus; + } else if (!(cctl & PL080_CONTROL_SRC_INCR)) { + *mbus = dst_bus; + *sbus = src_bus; + } else { + if (dst_bus->buswidth == 4) { + *mbus = dst_bus; + *sbus = src_bus; + } else if (src_bus->buswidth == 4) { + *mbus = src_bus; + *sbus = dst_bus; + } else if (dst_bus->buswidth == 2) { + *mbus = dst_bus; + *sbus = src_bus; + } else if (src_bus->buswidth == 2) { + *mbus = src_bus; + *sbus = dst_bus; + } else { + /* src_bus->buswidth == 1 */ + *mbus = dst_bus; + *sbus = src_bus; + } + } +} + +/* + * Fills in one LLI for a certain transfer descriptor + * and advance the counter + */ +int pl08x_fill_lli_for_desc(struct pl08x_driver_data *pl08x, + struct pl08x_txd *txd, int num_llis, int len, + u32 cctl, u32 *remainder) +{ + struct lli *llis_va = txd->llis_va; + struct lli *llis_bus = (struct lli *) txd->llis_bus; + + BUG_ON(num_llis >= MAX_NUM_TSFR_LLIS); + + llis_va[num_llis].cctl = cctl; + llis_va[num_llis].src = txd->srcbus.addr; + llis_va[num_llis].dst = txd->dstbus.addr; + + /* + * On versions with dual masters, you can optionally AND on + * PL080_LLI_LM_AHB2 to the LLI to tell the hardware to read + * in new LLIs with that controller, but we always try to + * choose AHB1 to point into memory. The idea is to have AHB2 + * fixed on the peripheral and AHB1 messing around in the + * memory. So we don't manipulate this bit currently. + */ + + llis_va[num_llis].next = + (dma_addr_t)((u32) &(llis_bus[num_llis + 1])); + + if (cctl & PL080_CONTROL_SRC_INCR) + txd->srcbus.addr += len; + if (cctl & PL080_CONTROL_DST_INCR) + txd->dstbus.addr += len; + + *remainder -= len; + + return num_llis + 1; +} + +/* + * Return number of bytes to fill to boundary, or len + */ +static inline u32 pl08x_pre_boundary(u32 addr, u32 len) +{ + u32 boundary; + + boundary = ((addr >> PL08X_BOUNDARY_SHIFT) + 1) + << PL08X_BOUNDARY_SHIFT; + + if (boundary < addr + len) + return boundary - addr; + else + return 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_channel_data *cd = txd->cd; + struct pl08x_bus_data *mbus, *sbus; + u32 remainder; + int num_llis = 0; + u32 cctl; + int max_bytes_per_lli; + int total_bytes = 0; + struct lli *llis_va; + struct lli *llis_bus; + + if (!txd) { + dev_err(&pl08x->adev->dev, "%s no descriptor\n", __func__); + return 0; + } + + 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++; + + /* + * Initialize bus values for this transfer + * from the passed optimal values + */ + if (!cd) { + dev_err(&pl08x->adev->dev, "%s no channel data\n", __func__); + return 0; + } + + /* Get the default CCTL from the platform data */ + cctl = cd->cctl; + + /* + * On the PL080 we have two bus masters and we + * should select one for source and one for + * destination. We try to use AHB2 for the + * bus which does not increment (typically the + * peripheral) else we just choose something. + */ + cctl &= ~(PL080_CONTROL_DST_AHB2 | PL080_CONTROL_SRC_AHB2); + if (pl08x->vd->dualmaster) { + if (cctl & PL080_CONTROL_SRC_INCR) + /* Source increments, use AHB2 for destination */ + cctl |= PL080_CONTROL_DST_AHB2; + else if (cctl & PL080_CONTROL_DST_INCR) + /* Destination increments, use AHB2 for source */ + cctl |= PL080_CONTROL_SRC_AHB2; + else + /* Just pick something, source AHB1 dest AHB2 */ + cctl |= PL080_CONTROL_DST_AHB2; + } + + /* Find maximum width of the source bus */ + txd->srcbus.maxwidth = + pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_SWIDTH_MASK) >> + PL080_CONTROL_SWIDTH_SHIFT); + + /* Find maximum width of the destination bus */ + txd->dstbus.maxwidth = + pl08x_get_bytes_for_cctl((cctl & PL080_CONTROL_DWIDTH_MASK) >> + PL080_CONTROL_DWIDTH_SHIFT); + + /* Set up the bus widths to the maximum */ + txd->srcbus.buswidth = txd->srcbus.maxwidth; + txd->dstbus.buswidth = txd->dstbus.maxwidth; + dev_vdbg(&pl08x->adev->dev, + "%s source bus is %d bytes wide, dest bus is %d bytes wide\n", + __func__, txd->srcbus.buswidth, txd->dstbus.buswidth); + + + /* + * Bytes transferred == tsize * MIN(buswidths), not max(buswidths) + */ + max_bytes_per_lli = min(txd->srcbus.buswidth, txd->dstbus.buswidth) * + PL080_CONTROL_TRANSFER_SIZE_MASK; + dev_vdbg(&pl08x->adev->dev, + "%s max bytes per lli = %d\n", + __func__, max_bytes_per_lli); + + /* We need to count this down to zero */ + remainder = txd->len; + dev_vdbg(&pl08x->adev->dev, + "%s remainder = %d\n", + __func__, remainder); + + /* + * Choose bus to align to + * - prefers destination bus if both available + * - if fixed address on one bus chooses other + * - modifies cctl to choose an apropriate master + */ + pl08x_choose_master_bus(&txd->srcbus, &txd->dstbus, + &mbus, &sbus, cctl); + + + /* + * The lowest bit of the LLI register + * is also used to indicate which master to + * use for reading the LLIs. + */ + + if (txd->len < mbus->buswidth) { + /* + * Less than a bus width available + * - send as single bytes + */ + while (remainder) { + dev_vdbg(&pl08x->adev->dev, + "%s single byte LLIs for a transfer of " + "less than a bus width (remain %08x)\n", + __func__, remainder); + cctl = pl08x_cctl_bits(cctl, 1, 1, 1); + num_llis = + pl08x_fill_lli_for_desc(pl08x, txd, num_llis, 1, + cctl, &remainder); + total_bytes++; + } + } else { + /* + * Make one byte LLIs until master bus is aligned + * - slave will then be aligned also + */ + while ((mbus->addr) % (mbus->buswidth)) { + dev_vdbg(&pl08x->adev->dev, + "%s adjustment lli for less than bus width " + "(remain %08x)\n", + __func__, remainder); + cctl = pl08x_cctl_bits(cctl, 1, 1, 1); + num_llis = pl08x_fill_lli_for_desc + (pl08x, txd, num_llis, 1, cctl, &remainder); + 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 (remainder > (mbus->buswidth - 1)) { + int lli_len, target_len; + int tsize; + int odd_bytes; + + /* + * If enough left try to send max possible, + * otherwise try to send the remainder + */ + target_len = remainder; + if (remainder > max_bytes_per_lli) + target_len = max_bytes_per_lli; + + /* + * Set bus lengths for incrementing busses + * to number of bytes which fill to next memory + * boundary + */ + if (cctl & PL080_CONTROL_SRC_INCR) + txd->srcbus.fill_bytes = + pl08x_pre_boundary( + txd->srcbus.addr, + remainder); + else + txd->srcbus.fill_bytes = + max_bytes_per_lli; + + if (cctl & PL080_CONTROL_DST_INCR) + txd->dstbus.fill_bytes = + pl08x_pre_boundary( + txd->dstbus.addr, + remainder); + else + txd->dstbus.fill_bytes = + max_bytes_per_lli; + + /* + * Find the nearest + */ + lli_len = min(txd->srcbus.fill_bytes, + txd->dstbus.fill_bytes); + + BUG_ON(lli_len > remainder); + + if (lli_len <= 0) { + dev_err(&pl08x->adev->dev, + "%s lli_len is %d, <= 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 + */ + odd_bytes = lli_len % mbus->buswidth; + /* + * - and that we are working in multiples + * of the bus widths + */ + 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 %08x, lli of %08x bytes in txd of %08x\n", + __func__, target_len, lli_len, txd->len); + } + + cctl = pl08x_cctl_bits(cctl, + txd->srcbus.buswidth, + txd->dstbus.buswidth, + tsize); + + dev_vdbg(&pl08x->adev->dev, + "%s fill lli with single lli chunk of size %08x (remainder %08x)\n", + __func__, lli_len, remainder); + num_llis = pl08x_fill_lli_for_desc(pl08x, txd, + num_llis, lli_len, cctl, + &remainder); + total_bytes += lli_len; + } + + + if (odd_bytes) { + /* + * Creep past the boundary, + * maintaining master alignment + */ + int j; + for (j = 0; (j < mbus->buswidth) + && (remainder); j++) { + cctl = pl08x_cctl_bits(cctl, 1, 1, 1); + dev_vdbg(&pl08x->adev->dev, + "%s align with boundardy, single byte (remain %08x)\n", + __func__, remainder); + num_llis = + pl08x_fill_lli_for_desc(pl08x, + txd, num_llis, 1, + cctl, &remainder); + total_bytes++; + } + } + } + + /* + * Send any odd bytes + */ + if (remainder < 0) { + dev_err(&pl08x->adev->dev, "%s remainder not fitted 0x%08x bytes\n", + __func__, remainder); + return 0; + } + + while (remainder) { + cctl = pl08x_cctl_bits(cctl, 1, 1, 1); + dev_vdbg(&pl08x->adev->dev, + "%s align with boundardy, single odd byte (remain %d)\n", + __func__, remainder); + num_llis = pl08x_fill_lli_for_desc(pl08x, txd, num_llis, + 1, cctl, &remainder); + 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%08x from size 0x%08x\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; + } + /* + * Decide whether this is a loop or a terminated transfer + */ + llis_va = txd->llis_va; + llis_bus = (struct lli *) txd->llis_bus; + + if (cd->circular_buffer) { + /* + * Loop the circular buffer so that the next element + * points back to the beginning of the LLI. + */ + llis_va[num_llis - 1].next = + (dma_addr_t)((unsigned int)&(llis_bus[0])); + } else { + /* + * On non-circular buffers, the final LLI terminates + * the LLI. + */ + llis_va[num_llis - 1].next = 0; + /* + * The final LLI element shall also fire an interrupt + */ + llis_va[num_llis - 1].cctl |= PL080_CONTROL_TC_IRQ_EN; + } + + /* Now store the channel register values */ + txd->csrc = llis_va[0].src; + txd->cdst = llis_va[0].dst; + if (num_llis > 1) + txd->clli = llis_va[0].next; + else + txd->clli = 0; + + txd->cctl = llis_va[0].cctl; + /* ccfg will be set at physical channel allocation time */ + +#ifdef VERBOSE_DEBUG + { + int i; + + for (i = 0; i < num_llis; i++) { + dev_vdbg(&pl08x->adev->dev, + "lli %d @%p: csrc=%08x, cdst=%08x, cctl=%08x, clli=%08x\n", + i, + &llis_va[i], + llis_va[i].src, + llis_va[i].dst, + llis_va[i].cctl, + llis_va[i].next + ); + } + } +#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) +{ + if (!txd) + dev_err(&pl08x->adev->dev, + "%s no descriptor to free\n", + __func__); + + /* 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->desc_list)) { + list_for_each_entry_safe(txdi, + next, &plchan->desc_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; + } + + 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 = ch; + + return 0; +} + +static dma_cookie_t pl08x_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct pl08x_dma_chan *plchan = to_pl08x_chan(tx->chan); + + atomic_inc(&plchan->last_issued); + tx->cookie = atomic_read(&plchan->last_issued); + /* This unlock follows the lock in the prep() function */ + spin_unlock_irqrestore(&plchan->lock, plchan->lockflags); + + 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 - could schedule where indicated. + * 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 = atomic_read(&plchan->last_issued); + 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; + } + + /* + * schedule(); could be inserted here + */ + + /* + * This cookie not complete yet + */ + last_used = atomic_read(&plchan->last_issued); + 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 void 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; + u32 maxburst; + u32 cctl = 0; + /* Mask out all except src and dst channel */ + u32 ccfg = cd->ccfg & 0x000003DEU; + int i = 0; + + /* Transfer direction */ + plchan->runtime_direction = config->direction; + if (config->direction == DMA_TO_DEVICE) { + plchan->runtime_addr = config->dst_addr; + cctl |= PL080_CONTROL_SRC_INCR; + ccfg |= PL080_FLOW_MEM2PER << PL080_CONFIG_FLOW_CONTROL_SHIFT; + addr_width = config->dst_addr_width; + maxburst = config->dst_maxburst; + } else if (config->direction == DMA_FROM_DEVICE) { + plchan->runtime_addr = config->src_addr; + cctl |= PL080_CONTROL_DST_INCR; + ccfg |= PL080_FLOW_PER2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT; + addr_width = config->src_addr_width; + maxburst = config->src_maxburst; + } else { + dev_err(&pl08x->adev->dev, + "bad runtime_config: alien transfer direction\n"); + return; + } + + 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; + } + + /* + * Now decide on a maxburst: + * If this channel will only request single transfers, set + * this down to ONE element. + */ + if (plchan->cd->single) { + cctl |= (PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT) | + (PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT); + } else { + while (i < ARRAY_SIZE(burst_sizes)) { + if (burst_sizes[i].burstwords <= maxburst) + break; + i++; + } + cctl |= burst_sizes[i].reg; + } + + /* Access the cell in privileged mode, non-bufferable, non-cacheable */ + cctl &= ~PL080_CONTROL_PROT_MASK; + cctl |= PL080_CONTROL_PROT_SYS; + + /* Modify the default channel data to fit PrimeCell request */ + cd->cctl = cctl; + cd->ccfg = ccfg; + + dev_dbg(&pl08x->adev->dev, + "configured channel %s (%s) for %s, data width %d, " + "maxburst %d words, LE, CCTL=%08x, CCFG=%08x\n", + dma_chan_name(chan), plchan->name, + (config->direction == DMA_FROM_DEVICE) ? "RX" : "TX", + addr_width, + maxburst, + cctl, ccfg); +} + +/* + * 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); + struct pl08x_driver_data *pl08x = plchan->host; + unsigned long flags; + + spin_lock_irqsave(&plchan->lock, flags); + /* Something is already active */ + if (plchan->at) { + spin_unlock_irqrestore(&plchan->lock, flags); + return; + } + + /* Didn't get a physical channel so waiting for it ... */ + if (plchan->state == PL08X_CHAN_WAITING) + return; + + /* Take the first element in the queue and execute it */ + if (!list_empty(&plchan->desc_list)) { + struct pl08x_txd *next; + + next = list_first_entry(&plchan->desc_list, + struct pl08x_txd, + node); + list_del(&next->node); + plchan->at = next; + plchan->state = PL08X_CHAN_RUNNING; + + /* Configure the physical channel for the active txd */ + pl08x_config_phychan_for_txd(plchan); + pl08x_set_cregs(pl08x, plchan->phychan); + pl08x_enable_phy_chan(pl08x, plchan->phychan); + } + + spin_unlock_irqrestore(&plchan->lock, flags); +} + +static int pl08x_prep_channel_resources(struct pl08x_dma_chan *plchan, + struct pl08x_txd *txd) +{ + int num_llis; + struct pl08x_driver_data *pl08x = plchan->host; + int ret; + + num_llis = pl08x_fill_llis_for_desc(pl08x, txd); + + if (!num_llis) + return -EINVAL; + + spin_lock_irqsave(&plchan->lock, plchan->lockflags); + + /* + * If this device is not using a circular buffer then + * queue this new descriptor for transfer. + * The descriptor for a circular buffer continues + * to be used until the channel is freed. + */ + if (txd->cd->circular_buffer) + dev_err(&pl08x->adev->dev, + "%s attempting to queue a circular buffer\n", + __func__); + else + list_add_tail(&txd->node, + &plchan->desc_list); + + /* + * 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 available, we will + * stack up the memcpy channels until there is a channel + * available to handle it whereas slave transfers may + * have been denied due to platform channel muxing restrictions + * and since there is no guarantee that this will ever be + * resolved, and since the signal must be aquired AFTER + * aquiring the physical channel, we will let them be NACK:ed + * with -EBUSY here. The drivers can alway retry the prep() + * call if they are eager on doing this using DMA. + */ + if (plchan->slave) { + pl08x_free_txd_list(pl08x, plchan); + spin_unlock_irqrestore(&plchan->lock, plchan->lockflags); + return -EBUSY; + } + /* Do this memcpy whenever there is a channel ready */ + plchan->state = PL08X_CHAN_WAITING; + plchan->waiting = txd; + } 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; + + /* + * Notice that we leave plchan->lock locked on purpose: + * it will be unlocked in the subsequent tx_submit() + * call. This is a consequence of the current API. + */ + + return 0; +} + +/* + * 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 = kzalloc(sizeof(struct pl08x_txd), GFP_NOWAIT); + if (!txd) { + dev_err(&pl08x->adev->dev, + "%s no memory for descriptor\n", __func__); + return NULL; + } + + dma_async_tx_descriptor_init(&txd->tx, chan); + txd->direction = DMA_NONE; + txd->srcbus.addr = src; + txd->dstbus.addr = dest; + + /* Set platform data for m2m */ + txd->cd = &pl08x->pd->memcpy_channel; + /* Both to be incremented or the code will break */ + txd->cd->cctl |= PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR; + txd->tx.tx_submit = pl08x_tx_submit; + txd->tx.callback = NULL; + txd->tx.callback_param = NULL; + txd->len = len; + + INIT_LIST_HEAD(&txd->node); + ret = pl08x_prep_channel_resources(plchan, txd); + if (ret) + return NULL; + /* + * NB: the channel lock is held at this point so tx_submit() + * must be called in direct succession. + */ + + return &txd->tx; +} + +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; + 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 = kzalloc(sizeof(struct pl08x_txd), GFP_NOWAIT); + if (!txd) { + dev_err(&pl08x->adev->dev, "%s no txd\n", __func__); + return NULL; + } + + dma_async_tx_descriptor_init(&txd->tx, chan); + + 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_TO_DEVICE) { + txd->srcbus.addr = sgl->dma_address; + if (plchan->runtime_addr) + txd->dstbus.addr = plchan->runtime_addr; + else + txd->dstbus.addr = plchan->cd->addr; + } else if (direction == DMA_FROM_DEVICE) { + if (plchan->runtime_addr) + txd->srcbus.addr = plchan->runtime_addr; + else + txd->srcbus.addr = plchan->cd->addr; + txd->dstbus.addr = sgl->dma_address; + } else { + dev_err(&pl08x->adev->dev, + "%s direction unsupported\n", __func__); + return NULL; + } + txd->cd = plchan->cd; + txd->tx.tx_submit = pl08x_tx_submit; + txd->tx.callback = NULL; + txd->tx.callback_param = NULL; + txd->len = sgl->length; + INIT_LIST_HEAD(&txd->node); + + ret = pl08x_prep_channel_resources(plchan, txd); + if (ret) + return NULL; + /* + * NB: the channel lock is held at this point so tx_submit() + * must be called in direct succession. + */ + + 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) { + dma_set_runtime_config(chan, + (struct dma_slave_config *) + arg); + return 0; + } + + /* + * 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_stop_phy_chan(plchan->phychan); + + /* + * Mark physical channel as free and free any slave + * signal + */ + 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; + } + /* Stop any pending tasklet */ + tasklet_disable(&plchan->tasklet); + /* 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 implictly clear bit 1 and that means little-endian mode */ + val |= PL080_CONFIG_ENABLE; + writel(val, pl08x->base + PL080_CONFIG); +} + +static void pl08x_tasklet(unsigned long data) +{ + struct pl08x_dma_chan *plchan = (struct pl08x_dma_chan *) data; + struct pl08x_phy_chan *phychan = plchan->phychan; + struct pl08x_driver_data *pl08x = plchan->host; + + if (!plchan) + BUG(); + + spin_lock(&plchan->lock); + + if (plchan->at) { + dma_async_tx_callback callback = + plchan->at->tx.callback; + void *callback_param = + plchan->at->tx.callback_param; + + /* + * Update last completed + */ + plchan->lc = + (plchan->at->tx.cookie); + + /* + * Callback to signal completion + */ + if (callback) + callback(callback_param); + + /* + * Device callbacks should NOT clear + * the current transaction on the channel + * Linus: sometimes they should? + */ + if (!plchan->at) + BUG(); + + /* + * Free the descriptor if it's not for a device + * using a circular buffer + */ + if (!plchan->at->cd->circular_buffer) { + pl08x_free_txd(pl08x, plchan->at); + plchan->at = NULL; + } + /* + * else descriptor for circular + * buffers only freed when + * client has disabled dma + */ + } + /* + * If a new descriptor is queued, set it up + * plchan->at is NULL here + */ + if (!list_empty(&plchan->desc_list)) { + struct pl08x_txd *next; + + next = list_first_entry(&plchan->desc_list, + struct pl08x_txd, + node); + list_del(&next->node); + plchan->at = next; + /* Configure the physical channel for the next txd */ + pl08x_config_phychan_for_txd(plchan); + pl08x_set_cregs(pl08x, plchan->phychan); + pl08x_enable_phy_chan(pl08x, plchan->phychan); + } else { + struct pl08x_dma_chan *waiting = NULL; + + /* + * No more jobs, so free up the physical channel + * Free any allocated signal on slave transfers too + */ + if ((phychan->signal >= 0) && pl08x->pd->put_signal) { + pl08x->pd->put_signal(plchan); + phychan->signal = -1; + } + pl08x_put_phy_channel(pl08x, phychan); + plchan->phychan = NULL; + 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->state = PL08X_CHAN_RUNNING; + waiting->waiting = NULL; + pl08x_issue_pending(&waiting->chan); + break; + } + } + } + + spin_unlock(&plchan->lock); +} + +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; + } + } + dev_info(&pl08x->adev->dev, + "initialize virtual channel \"%s\"\n", + chan->name); + + chan->chan.device = dmadev; + atomic_set(&chan->last_issued, 0); + chan->lc = atomic_read(&chan->last_issued); + + spin_lock_init(&chan->lock); + INIT_LIST_HEAD(&chan->desc_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, struct amba_id *id) +{ + struct pl08x_driver_data *pl08x; + 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; + + /* 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, + vd->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, "ARM(R) %s DMA block initialized @%08x\n", + vd->name, adev->res.start); + 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 = { + .name = "PL080", + .channels = 8, + .dualmaster = true, +}; + +static struct vendor_data vendor_pl081 = { + .name = "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); |