linux/drivers/dma/amba-pl08x.c
Russell King 4d66164e99 dmaengine: PL08x: Fix trivial build error
Something changed during the 3.1 merge window in the include files
which now causes the pl08x DMA engine driver to fail to build.  Fix
this by adding the now necessary dma-mapping.h include:

drivers/dma/amba-pl08x.c: In function ■pl08x_unmap_buffers■:
drivers/dma/amba-pl08x.c:1524: error: implicit declaration of function ■dma_unmap_single■
drivers/dma/amba-pl08x.c:1527: error: implicit declaration of function ■dma_unmap_page■

Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-08-09 08:42:28 +01:00

2081 lines
54 KiB
C

/*
* 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/dma-mapping.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)
/* Size (bytes) of each LLI buffer allocated for one transfer */
# define PL08X_LLI_TSFR_SIZE 0x2000
/* Maximum times we call dma_pool_alloc on this pool without freeing */
#define MAX_NUM_TSFR_LLIS (PL08X_LLI_TSFR_SIZE/sizeof(struct pl08x_lli))
#define PL08X_ALIGN 8
static inline struct pl08x_dma_chan *to_pl08x_chan(struct dma_chan *chan)
{
return container_of(chan, struct pl08x_dma_chan, chan);
}
static inline struct pl08x_txd *to_pl08x_txd(struct dma_async_tx_descriptor *tx)
{
return container_of(tx, struct pl08x_txd, tx);
}
/*
* Physical channel handling
*/
/* Whether a certain channel is busy or not */
static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch)
{
unsigned int val;
val = readl(ch->base + PL080_CH_CONFIG);
return val & PL080_CONFIG_ACTIVE;
}
/*
* Set the initial DMA register values i.e. those for the first LLI
* The next LLI pointer and the configuration interrupt bit have
* been set when the LLIs were constructed. Poke them into the hardware
* and start the transfer.
*/
static void pl08x_start_txd(struct pl08x_dma_chan *plchan,
struct pl08x_txd *txd)
{
struct pl08x_driver_data *pl08x = plchan->host;
struct pl08x_phy_chan *phychan = plchan->phychan;
struct pl08x_lli *lli = &txd->llis_va[0];
u32 val;
plchan->at = txd;
/* Wait for channel inactive */
while (pl08x_phy_channel_busy(phychan))
cpu_relax();
dev_vdbg(&pl08x->adev->dev,
"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "
"clli=0x%08x, cctl=0x%08x, ccfg=0x%08x\n",
phychan->id, lli->src, lli->dst, lli->lli, lli->cctl,
txd->ccfg);
writel(lli->src, phychan->base + PL080_CH_SRC_ADDR);
writel(lli->dst, phychan->base + PL080_CH_DST_ADDR);
writel(lli->lli, phychan->base + PL080_CH_LLI);
writel(lli->cctl, phychan->base + PL080_CH_CONTROL);
writel(txd->ccfg, phychan->base + PL080_CH_CONFIG);
/* Enable the DMA channel */
/* Do not access config register until channel shows as disabled */
while (readl(pl08x->base + PL080_EN_CHAN) & (1 << phychan->id))
cpu_relax();
/* Do not access config register until channel shows as inactive */
val = readl(phychan->base + PL080_CH_CONFIG);
while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE))
val = readl(phychan->base + PL080_CH_CONFIG);
writel(val | PL080_CONFIG_ENABLE, phychan->base + PL080_CH_CONFIG);
}
/*
* Pause the channel by setting the HALT bit.
*
* For M->P transfers, pause the DMAC first and then stop the peripheral -
* the FIFO can only drain if the peripheral is still requesting data.
* (note: this can still timeout if the DMAC FIFO never drains of data.)
*
* For P->M transfers, disable the peripheral first to stop it filling
* the DMAC FIFO, and then pause the DMAC.
*/
static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
{
u32 val;
int timeout;
/* Set the HALT bit and wait for the FIFO to drain */
val = readl(ch->base + PL080_CH_CONFIG);
val |= PL080_CONFIG_HALT;
writel(val, ch->base + PL080_CH_CONFIG);
/* Wait for channel inactive */
for (timeout = 1000; timeout; timeout--) {
if (!pl08x_phy_channel_busy(ch))
break;
udelay(1);
}
if (pl08x_phy_channel_busy(ch))
pr_err("pl08x: channel%u timeout waiting for pause\n", ch->id);
}
static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
{
u32 val;
/* Clear the HALT bit */
val = readl(ch->base + PL080_CH_CONFIG);
val &= ~PL080_CONFIG_HALT;
writel(val, ch->base + PL080_CH_CONFIG);
}
/*
* pl08x_terminate_phy_chan() stops the channel, clears the FIFO and
* clears any pending interrupt status. This should not be used for
* an on-going transfer, but as a method of shutting down a channel
* (eg, when it's no longer used) or terminating a transfer.
*/
static void pl08x_terminate_phy_chan(struct pl08x_driver_data *pl08x,
struct pl08x_phy_chan *ch)
{
u32 val = readl(ch->base + PL080_CH_CONFIG);
val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
PL080_CONFIG_TC_IRQ_MASK);
writel(val, ch->base + PL080_CH_CONFIG);
writel(1 << ch->id, pl08x->base + PL080_ERR_CLEAR);
writel(1 << ch->id, pl08x->base + PL080_TC_CLEAR);
}
static inline u32 get_bytes_in_cctl(u32 cctl)
{
/* The source width defines the number of bytes */
u32 bytes = cctl & PL080_CONTROL_TRANSFER_SIZE_MASK;
switch (cctl >> PL080_CONTROL_SWIDTH_SHIFT) {
case PL080_WIDTH_8BIT:
break;
case PL080_WIDTH_16BIT:
bytes *= 2;
break;
case PL080_WIDTH_32BIT:
bytes *= 4;
break;
}
return bytes;
}
/* The channel should be paused when calling this */
static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan)
{
struct pl08x_phy_chan *ch;
struct pl08x_txd *txd;
unsigned long flags;
size_t bytes = 0;
spin_lock_irqsave(&plchan->lock, flags);
ch = plchan->phychan;
txd = plchan->at;
/*
* Follow the LLIs to get the number of remaining
* bytes in the currently active transaction.
*/
if (ch && txd) {
u32 clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2;
/* First get the remaining bytes in the active transfer */
bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL));
if (clli) {
struct pl08x_lli *llis_va = txd->llis_va;
dma_addr_t llis_bus = txd->llis_bus;
int index;
BUG_ON(clli < llis_bus || clli >= llis_bus +
sizeof(struct pl08x_lli) * MAX_NUM_TSFR_LLIS);
/*
* Locate the next LLI - as this is an array,
* it's simple maths to find.
*/
index = (clli - llis_bus) / sizeof(struct pl08x_lli);
for (; index < MAX_NUM_TSFR_LLIS; index++) {
bytes += get_bytes_in_cctl(llis_va[index].cctl);
/*
* A LLI pointer of 0 terminates the LLI list
*/
if (!llis_va[index].lli)
break;
}
}
}
/* Sum up all queued transactions */
if (!list_empty(&plchan->pend_list)) {
struct pl08x_txd *txdi;
list_for_each_entry(txdi, &plchan->pend_list, node) {
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_bus_data srcbus;
struct pl08x_bus_data dstbus;
size_t remainder;
u32 lli_bus;
};
/*
* 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);
llis_va[num_llis].lli |= bd->lli_bus;
if (cctl & PL080_CONTROL_SRC_INCR)
bd->srcbus.addr += len;
if (cctl & PL080_CONTROL_DST_INCR)
bd->dstbus.addr += len;
BUG_ON(bd->remainder < len);
bd->remainder -= len;
}
/*
* 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.srcbus.addr = txd->src_addr;
bd.dstbus.addr = txd->dst_addr;
bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0;
/* 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;
/*
* Bytes transferred == tsize * MIN(buswidths), not max(buswidths)
*/
max_bytes_per_lli = min(bd.srcbus.buswidth, bd.dstbus.buswidth) *
PL080_CONTROL_TRANSFER_SIZE_MASK;
/* We need to count this down to zero */
bd.remainder = txd->len;
/*
* 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);
dev_vdbg(&pl08x->adev->dev, "src=0x%08x%s/%u dst=0x%08x%s/%u len=%zu llimax=%zu\n",
bd.srcbus.addr, cctl & PL080_CONTROL_SRC_INCR ? "+" : "",
bd.srcbus.buswidth,
bd.dstbus.addr, cctl & PL080_CONTROL_DST_INCR ? "+" : "",
bd.dstbus.buswidth,
bd.remainder, max_bytes_per_lli);
dev_vdbg(&pl08x->adev->dev, "mbus=%s sbus=%s\n",
mbus == &bd.srcbus ? "src" : "dst",
sbus == &bd.srcbus ? "src" : "dst");
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;
dev_vdbg(&pl08x->adev->dev,
"%-3s %-9s %-10s %-10s %-10s %s\n",
"lli", "", "csrc", "cdst", "clli", "cctl");
for (i = 0; i < num_llis; i++) {
dev_vdbg(&pl08x->adev->dev,
"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x\n",
i, &llis_va[i], llis_va[i].src,
llis_va[i].dst, llis_va[i].lli, llis_va[i].cctl
);
}
}
#endif
return num_llis;
}
/* You should call this with the struct pl08x lock held */
static void pl08x_free_txd(struct pl08x_driver_data *pl08x,
struct pl08x_txd *txd)
{
/* 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 {
u32 burstwords;
u32 reg;
};
static const struct burst_table burst_sizes[] = {
{
.burstwords = 256,
.reg = PL080_BSIZE_256,
},
{
.burstwords = 128,
.reg = PL080_BSIZE_128,
},
{
.burstwords = 64,
.reg = PL080_BSIZE_64,
},
{
.burstwords = 32,
.reg = PL080_BSIZE_32,
},
{
.burstwords = 16,
.reg = PL080_BSIZE_16,
},
{
.burstwords = 8,
.reg = PL080_BSIZE_8,
},
{
.burstwords = 4,
.reg = PL080_BSIZE_4,
},
{
.burstwords = 0,
.reg = PL080_BSIZE_1,
},
};
/*
* Given the source and destination available bus masks, select which
* will be routed to each port. We try to have source and destination
* on separate ports, but always respect the allowable settings.
*/
static u32 pl08x_select_bus(u8 src, u8 dst)
{
u32 cctl = 0;
if (!(dst & PL08X_AHB1) || ((dst & PL08X_AHB2) && (src & PL08X_AHB1)))
cctl |= PL080_CONTROL_DST_AHB2;
if (!(src & PL08X_AHB1) || ((src & PL08X_AHB2) && !(dst & PL08X_AHB2)))
cctl |= PL080_CONTROL_SRC_AHB2;
return cctl;
}
static u32 pl08x_cctl(u32 cctl)
{
cctl &= ~(PL080_CONTROL_SRC_AHB2 | PL080_CONTROL_DST_AHB2 |
PL080_CONTROL_SRC_INCR | PL080_CONTROL_DST_INCR |
PL080_CONTROL_PROT_MASK);
/* Access the cell in privileged mode, non-bufferable, non-cacheable */
return cctl | PL080_CONTROL_PROT_SYS;
}
static u32 pl08x_width(enum dma_slave_buswidth width)
{
switch (width) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
return PL080_WIDTH_8BIT;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
return PL080_WIDTH_16BIT;
case DMA_SLAVE_BUSWIDTH_4_BYTES:
return PL080_WIDTH_32BIT;
default:
return ~0;
}
}
static u32 pl08x_burst(u32 maxburst)
{
int i;
for (i = 0; i < ARRAY_SIZE(burst_sizes); i++)
if (burst_sizes[i].burstwords <= maxburst)
break;
return burst_sizes[i].reg;
}
static int dma_set_runtime_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
struct pl08x_driver_data *pl08x = plchan->host;
enum dma_slave_buswidth addr_width;
u32 width, burst, maxburst;
u32 cctl = 0;
if (!plchan->slave)
return -EINVAL;
/* Transfer direction */
plchan->runtime_direction = config->direction;
if (config->direction == DMA_TO_DEVICE) {
addr_width = config->dst_addr_width;
maxburst = config->dst_maxburst;
} else if (config->direction == DMA_FROM_DEVICE) {
addr_width = config->src_addr_width;
maxburst = config->src_maxburst;
} else {
dev_err(&pl08x->adev->dev,
"bad runtime_config: alien transfer direction\n");
return -EINVAL;
}
width = pl08x_width(addr_width);
if (width == ~0) {
dev_err(&pl08x->adev->dev,
"bad runtime_config: alien address width\n");
return -EINVAL;
}
cctl |= width << PL080_CONTROL_SWIDTH_SHIFT;
cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
/*
* If this channel will only request single transfers, set this
* down to ONE element. Also select one element if no maxburst
* is specified.
*/
if (plchan->cd->single)
maxburst = 1;
burst = pl08x_burst(maxburst);
cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
if (plchan->runtime_direction == DMA_FROM_DEVICE) {
plchan->src_addr = config->src_addr;
plchan->src_cctl = pl08x_cctl(cctl) | PL080_CONTROL_DST_INCR |
pl08x_select_bus(plchan->cd->periph_buses,
pl08x->mem_buses);
} else {
plchan->dst_addr = config->dst_addr;
plchan->dst_cctl = pl08x_cctl(cctl) | PL080_CONTROL_SRC_INCR |
pl08x_select_bus(pl08x->mem_buses,
plchan->cd->periph_buses);
}
dev_dbg(&pl08x->adev->dev,
"configured channel %s (%s) for %s, data width %d, "
"maxburst %d words, LE, CCTL=0x%08x\n",
dma_chan_name(chan), plchan->name,
(config->direction == DMA_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;
}
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->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;
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;
if (direction == DMA_TO_DEVICE) {
txd->ccfg |= PL080_FLOW_MEM2PER << PL080_CONFIG_FLOW_CONTROL_SHIFT;
txd->cctl = plchan->dst_cctl;
txd->src_addr = sgl->dma_address;
txd->dst_addr = plchan->dst_addr;
} else if (direction == DMA_FROM_DEVICE) {
txd->ccfg |= PL080_FLOW_PER2MEM << PL080_CONFIG_FLOW_CONTROL_SHIFT;
txd->cctl = plchan->src_cctl;
txd->src_addr = plchan->src_addr;
txd->dst_addr = sgl->dma_address;
} else {
dev_err(&pl08x->adev->dev,
"%s direction unsupported\n", __func__);
return NULL;
}
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;
}
static void pl08x_dma_slave_init(struct pl08x_dma_chan *chan)
{
u32 cctl = pl08x_cctl(chan->cd->cctl);
chan->slave = true;
chan->name = chan->cd->bus_id;
chan->src_addr = chan->cd->addr;
chan->dst_addr = chan->cd->addr;
chan->src_cctl = cctl | PL080_CONTROL_DST_INCR |
pl08x_select_bus(chan->cd->periph_buses, chan->host->mem_buses);
chan->dst_cctl = cctl | PL080_CONTROL_SRC_INCR |
pl08x_select_bus(chan->host->mem_buses, chan->cd->periph_buses);
}
/*
* Initialise the DMAC memcpy/slave channels.
* Make a local wrapper to hold required data
*/
static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x,
struct dma_device *dmadev,
unsigned int channels,
bool slave)
{
struct pl08x_dma_chan *chan;
int i;
INIT_LIST_HEAD(&dmadev->channels);
/*
* Register as many many memcpy as we have physical channels,
* we won't always be able to use all but the code will have
* to cope with that situation.
*/
for (i = 0; i < channels; i++) {
chan = kzalloc(sizeof(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->cd = &pl08x->pd->slave_channels[i];
pl08x_dma_slave_init(chan);
} else {
chan->cd = &pl08x->pd->memcpy_channel;
chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i);
if (!chan->name) {
kfree(chan);
return -ENOMEM;
}
}
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);