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pxa_dma.c
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/*
* Copyright 2015 Robert Jarzmik <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/err.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/platform_data/mmp_dma.h>
#include <linux/dmapool.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/of.h>
#include <linux/dma/pxa-dma.h>
#include "dmaengine.h"
#include "virt-dma.h"
#define DCSR(n) (0x0000 + ((n) << 2))
#define DALGN(n) 0x00a0
#define DINT 0x00f0
#define DDADR(n) (0x0200 + ((n) << 4))
#define DSADR(n) (0x0204 + ((n) << 4))
#define DTADR(n) (0x0208 + ((n) << 4))
#define DCMD(n) (0x020c + ((n) << 4))
#define PXA_DCSR_RUN BIT(31) /* Run Bit (read / write) */
#define PXA_DCSR_NODESC BIT(30) /* No-Descriptor Fetch (read / write) */
#define PXA_DCSR_STOPIRQEN BIT(29) /* Stop Interrupt Enable (R/W) */
#define PXA_DCSR_REQPEND BIT(8) /* Request Pending (read-only) */
#define PXA_DCSR_STOPSTATE BIT(3) /* Stop State (read-only) */
#define PXA_DCSR_ENDINTR BIT(2) /* End Interrupt (read / write) */
#define PXA_DCSR_STARTINTR BIT(1) /* Start Interrupt (read / write) */
#define PXA_DCSR_BUSERR BIT(0) /* Bus Error Interrupt (read / write) */
#define PXA_DCSR_EORIRQEN BIT(28) /* End of Receive IRQ Enable (R/W) */
#define PXA_DCSR_EORJMPEN BIT(27) /* Jump to next descriptor on EOR */
#define PXA_DCSR_EORSTOPEN BIT(26) /* STOP on an EOR */
#define PXA_DCSR_SETCMPST BIT(25) /* Set Descriptor Compare Status */
#define PXA_DCSR_CLRCMPST BIT(24) /* Clear Descriptor Compare Status */
#define PXA_DCSR_CMPST BIT(10) /* The Descriptor Compare Status */
#define PXA_DCSR_EORINTR BIT(9) /* The end of Receive */
#define DRCMR_MAPVLD BIT(7) /* Map Valid (read / write) */
#define DRCMR_CHLNUM 0x1f /* mask for Channel Number (read / write) */
#define DDADR_DESCADDR 0xfffffff0 /* Address of next descriptor (mask) */
#define DDADR_STOP BIT(0) /* Stop (read / write) */
#define PXA_DCMD_INCSRCADDR BIT(31) /* Source Address Increment Setting. */
#define PXA_DCMD_INCTRGADDR BIT(30) /* Target Address Increment Setting. */
#define PXA_DCMD_FLOWSRC BIT(29) /* Flow Control by the source. */
#define PXA_DCMD_FLOWTRG BIT(28) /* Flow Control by the target. */
#define PXA_DCMD_STARTIRQEN BIT(22) /* Start Interrupt Enable */
#define PXA_DCMD_ENDIRQEN BIT(21) /* End Interrupt Enable */
#define PXA_DCMD_ENDIAN BIT(18) /* Device Endian-ness. */
#define PXA_DCMD_BURST8 (1 << 16) /* 8 byte burst */
#define PXA_DCMD_BURST16 (2 << 16) /* 16 byte burst */
#define PXA_DCMD_BURST32 (3 << 16) /* 32 byte burst */
#define PXA_DCMD_WIDTH1 (1 << 14) /* 1 byte width */
#define PXA_DCMD_WIDTH2 (2 << 14) /* 2 byte width (HalfWord) */
#define PXA_DCMD_WIDTH4 (3 << 14) /* 4 byte width (Word) */
#define PXA_DCMD_LENGTH 0x01fff /* length mask (max = 8K - 1) */
#define PDMA_ALIGNMENT 3
#define PDMA_MAX_DESC_BYTES (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
struct pxad_desc_hw {
u32 ddadr; /* Points to the next descriptor + flags */
u32 dsadr; /* DSADR value for the current transfer */
u32 dtadr; /* DTADR value for the current transfer */
u32 dcmd; /* DCMD value for the current transfer */
} __aligned(16);
struct pxad_desc_sw {
struct virt_dma_desc vd; /* Virtual descriptor */
int nb_desc; /* Number of hw. descriptors */
size_t len; /* Number of bytes xfered */
dma_addr_t first; /* First descriptor's addr */
/* At least one descriptor has an src/dst address not multiple of 8 */
bool misaligned;
bool cyclic;
struct dma_pool *desc_pool; /* Channel's used allocator */
struct pxad_desc_hw *hw_desc[]; /* DMA coherent descriptors */
};
struct pxad_phy {
int idx;
void __iomem *base;
struct pxad_chan *vchan;
};
struct pxad_chan {
struct virt_dma_chan vc; /* Virtual channel */
u32 drcmr; /* Requestor of the channel */
enum pxad_chan_prio prio; /* Required priority of phy */
/*
* At least one desc_sw in submitted or issued transfers on this channel
* has one address such as: addr % 8 != 0. This implies the DALGN
* setting on the phy.
*/
bool misaligned;
struct dma_slave_config cfg; /* Runtime config */
/* protected by vc->lock */
struct pxad_phy *phy;
struct dma_pool *desc_pool; /* Descriptors pool */
dma_cookie_t bus_error;
};
struct pxad_device {
struct dma_device slave;
int nr_chans;
int nr_requestors;
void __iomem *base;
struct pxad_phy *phys;
spinlock_t phy_lock; /* Phy association */
#ifdef CONFIG_DEBUG_FS
struct dentry *dbgfs_root;
struct dentry *dbgfs_state;
struct dentry **dbgfs_chan;
#endif
};
#define tx_to_pxad_desc(tx) \
container_of(tx, struct pxad_desc_sw, async_tx)
#define to_pxad_chan(dchan) \
container_of(dchan, struct pxad_chan, vc.chan)
#define to_pxad_dev(dmadev) \
container_of(dmadev, struct pxad_device, slave)
#define to_pxad_sw_desc(_vd) \
container_of((_vd), struct pxad_desc_sw, vd)
#define _phy_readl_relaxed(phy, _reg) \
readl_relaxed((phy)->base + _reg((phy)->idx))
#define phy_readl_relaxed(phy, _reg) \
({ \
u32 _v; \
_v = readl_relaxed((phy)->base + _reg((phy)->idx)); \
dev_vdbg(&phy->vchan->vc.chan.dev->device, \
"%s(): readl(%s): 0x%08x\n", __func__, #_reg, \
_v); \
_v; \
})
#define phy_writel(phy, val, _reg) \
do { \
writel((val), (phy)->base + _reg((phy)->idx)); \
dev_vdbg(&phy->vchan->vc.chan.dev->device, \
"%s(): writel(0x%08x, %s)\n", \
__func__, (u32)(val), #_reg); \
} while (0)
#define phy_writel_relaxed(phy, val, _reg) \
do { \
writel_relaxed((val), (phy)->base + _reg((phy)->idx)); \
dev_vdbg(&phy->vchan->vc.chan.dev->device, \
"%s(): writel_relaxed(0x%08x, %s)\n", \
__func__, (u32)(val), #_reg); \
} while (0)
static unsigned int pxad_drcmr(unsigned int line)
{
if (line < 64)
return 0x100 + line * 4;
return 0x1000 + line * 4;
}
/*
* Debug fs
*/
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/seq_file.h>
static int dbg_show_requester_chan(struct seq_file *s, void *p)
{
struct pxad_phy *phy = s->private;
int i;
u32 drcmr;
seq_printf(s, "DMA channel %d requester :\n", phy->idx);
for (i = 0; i < 70; i++) {
drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
if ((drcmr & DRCMR_CHLNUM) == phy->idx)
seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
!!(drcmr & DRCMR_MAPVLD));
}
return 0;
}
static inline int dbg_burst_from_dcmd(u32 dcmd)
{
int burst = (dcmd >> 16) & 0x3;
return burst ? 4 << burst : 0;
}
static int is_phys_valid(unsigned long addr)
{
return pfn_valid(__phys_to_pfn(addr));
}
#define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
#define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
static int dbg_show_descriptors(struct seq_file *s, void *p)
{
struct pxad_phy *phy = s->private;
int i, max_show = 20, burst, width;
u32 dcmd;
unsigned long phys_desc, ddadr;
struct pxad_desc_hw *desc;
phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
seq_printf(s, "[%03d] First descriptor unknown\n", 0);
for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
desc = phys_to_virt(phys_desc);
dcmd = desc->dcmd;
burst = dbg_burst_from_dcmd(dcmd);
width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
i, phys_desc, desc);
seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
dcmd,
PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
PXA_DCMD_STR(ENDIAN), burst, width,
dcmd & PXA_DCMD_LENGTH);
phys_desc = desc->ddadr;
}
if (i == max_show)
seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
i, phys_desc);
else
seq_printf(s, "[%03d] Desc at %08lx is %s\n",
i, phys_desc, phys_desc == DDADR_STOP ?
"DDADR_STOP" : "invalid");
return 0;
}
static int dbg_show_chan_state(struct seq_file *s, void *p)
{
struct pxad_phy *phy = s->private;
u32 dcsr, dcmd;
int burst, width;
static const char * const str_prio[] = {
"high", "normal", "low", "invalid"
};
dcsr = _phy_readl_relaxed(phy, DCSR);
dcmd = _phy_readl_relaxed(phy, DCMD);
burst = dbg_burst_from_dcmd(dcmd);
width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
seq_printf(s, "DMA channel %d\n", phy->idx);
seq_printf(s, "\tPriority : %s\n",
str_prio[(phy->idx & 0xf) / 4]);
seq_printf(s, "\tUnaligned transfer bit: %s\n",
_phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
"yes" : "no");
seq_printf(s, "\tDCSR = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
PXA_DCSR_STR(BUSERR));
seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
dcmd,
PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
return 0;
}
static int dbg_show_state(struct seq_file *s, void *p)
{
struct pxad_device *pdev = s->private;
/* basic device status */
seq_puts(s, "DMA engine status\n");
seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
return 0;
}
#define DBGFS_FUNC_DECL(name) \
static int dbg_open_##name(struct inode *inode, struct file *file) \
{ \
return single_open(file, dbg_show_##name, inode->i_private); \
} \
static const struct file_operations dbg_fops_##name = { \
.owner = THIS_MODULE, \
.open = dbg_open_##name, \
.llseek = seq_lseek, \
.read = seq_read, \
.release = single_release, \
}
DBGFS_FUNC_DECL(state);
DBGFS_FUNC_DECL(chan_state);
DBGFS_FUNC_DECL(descriptors);
DBGFS_FUNC_DECL(requester_chan);
static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
int ch, struct dentry *chandir)
{
char chan_name[11];
struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
struct dentry *chan_reqs = NULL;
void *dt;
scnprintf(chan_name, sizeof(chan_name), "%d", ch);
chan = debugfs_create_dir(chan_name, chandir);
dt = (void *)&pdev->phys[ch];
if (chan)
chan_state = debugfs_create_file("state", 0400, chan, dt,
&dbg_fops_chan_state);
if (chan_state)
chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
&dbg_fops_descriptors);
if (chan_descr)
chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
&dbg_fops_requester_chan);
if (!chan_reqs)
goto err_state;
return chan;
err_state:
debugfs_remove_recursive(chan);
return NULL;
}
static void pxad_init_debugfs(struct pxad_device *pdev)
{
int i;
struct dentry *chandir;
pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root)
goto err_root;
pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root,
pdev, &dbg_fops_state);
if (!pdev->dbgfs_state)
goto err_state;
pdev->dbgfs_chan =
kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state),
GFP_KERNEL);
if (!pdev->dbgfs_chan)
goto err_alloc;
chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
if (!chandir)
goto err_chandir;
for (i = 0; i < pdev->nr_chans; i++) {
pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
if (!pdev->dbgfs_chan[i])
goto err_chans;
}
return;
err_chans:
err_chandir:
kfree(pdev->dbgfs_chan);
err_alloc:
err_state:
debugfs_remove_recursive(pdev->dbgfs_root);
err_root:
pr_err("pxad: debugfs is not available\n");
}
static void pxad_cleanup_debugfs(struct pxad_device *pdev)
{
debugfs_remove_recursive(pdev->dbgfs_root);
}
#else
static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
#endif
/*
* In the transition phase where legacy pxa handling is done at the same time as
* mmp_dma, the DMA physical channel split between the 2 DMA providers is done
* through legacy_reserved. Legacy code reserves DMA channels by settings
* corresponding bits in legacy_reserved.
*/
static u32 legacy_reserved;
static u32 legacy_unavailable;
static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
{
int prio, i;
struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
struct pxad_phy *phy, *found = NULL;
unsigned long flags;
/*
* dma channel priorities
* ch 0 - 3, 16 - 19 <--> (0)
* ch 4 - 7, 20 - 23 <--> (1)
* ch 8 - 11, 24 - 27 <--> (2)
* ch 12 - 15, 28 - 31 <--> (3)
*/
spin_lock_irqsave(&pdev->phy_lock, flags);
for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
for (i = 0; i < pdev->nr_chans; i++) {
if (prio != (i & 0xf) >> 2)
continue;
if ((i < 32) && (legacy_reserved & BIT(i)))
continue;
phy = &pdev->phys[i];
if (!phy->vchan) {
phy->vchan = pchan;
found = phy;
if (i < 32)
legacy_unavailable |= BIT(i);
goto out_unlock;
}
}
}
out_unlock:
spin_unlock_irqrestore(&pdev->phy_lock, flags);
dev_dbg(&pchan->vc.chan.dev->device,
"%s(): phy=%p(%d)\n", __func__, found,
found ? found->idx : -1);
return found;
}
static void pxad_free_phy(struct pxad_chan *chan)
{
struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
unsigned long flags;
u32 reg;
int i;
dev_dbg(&chan->vc.chan.dev->device,
"%s(): freeing\n", __func__);
if (!chan->phy)
return;
/* clear the channel mapping in DRCMR */
if (chan->drcmr <= pdev->nr_requestors) {
reg = pxad_drcmr(chan->drcmr);
writel_relaxed(0, chan->phy->base + reg);
}
spin_lock_irqsave(&pdev->phy_lock, flags);
for (i = 0; i < 32; i++)
if (chan->phy == &pdev->phys[i])
legacy_unavailable &= ~BIT(i);
chan->phy->vchan = NULL;
chan->phy = NULL;
spin_unlock_irqrestore(&pdev->phy_lock, flags);
}
static bool is_chan_running(struct pxad_chan *chan)
{
u32 dcsr;
struct pxad_phy *phy = chan->phy;
if (!phy)
return false;
dcsr = phy_readl_relaxed(phy, DCSR);
return dcsr & PXA_DCSR_RUN;
}
static bool is_running_chan_misaligned(struct pxad_chan *chan)
{
u32 dalgn;
BUG_ON(!chan->phy);
dalgn = phy_readl_relaxed(chan->phy, DALGN);
return dalgn & (BIT(chan->phy->idx));
}
static void phy_enable(struct pxad_phy *phy, bool misaligned)
{
struct pxad_device *pdev;
u32 reg, dalgn;
if (!phy->vchan)
return;
dev_dbg(&phy->vchan->vc.chan.dev->device,
"%s(); phy=%p(%d) misaligned=%d\n", __func__,
phy, phy->idx, misaligned);
pdev = to_pxad_dev(phy->vchan->vc.chan.device);
if (phy->vchan->drcmr <= pdev->nr_requestors) {
reg = pxad_drcmr(phy->vchan->drcmr);
writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
}
dalgn = phy_readl_relaxed(phy, DALGN);
if (misaligned)
dalgn |= BIT(phy->idx);
else
dalgn &= ~BIT(phy->idx);
phy_writel_relaxed(phy, dalgn, DALGN);
phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
}
static void phy_disable(struct pxad_phy *phy)
{
u32 dcsr;
if (!phy)
return;
dcsr = phy_readl_relaxed(phy, DCSR);
dev_dbg(&phy->vchan->vc.chan.dev->device,
"%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
}
static void pxad_launch_chan(struct pxad_chan *chan,
struct pxad_desc_sw *desc)
{
dev_dbg(&chan->vc.chan.dev->device,
"%s(): desc=%p\n", __func__, desc);
if (!chan->phy) {
chan->phy = lookup_phy(chan);
if (!chan->phy) {
dev_dbg(&chan->vc.chan.dev->device,
"%s(): no free dma channel\n", __func__);
return;
}
}
chan->bus_error = 0;
/*
* Program the descriptor's address into the DMA controller,
* then start the DMA transaction
*/
phy_writel(chan->phy, desc->first, DDADR);
phy_enable(chan->phy, chan->misaligned);
}
static void set_updater_desc(struct pxad_desc_sw *sw_desc,
unsigned long flags)
{
struct pxad_desc_hw *updater =
sw_desc->hw_desc[sw_desc->nb_desc - 1];
dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
updater->ddadr = DDADR_STOP;
updater->dsadr = dma;
updater->dtadr = dma + 8;
updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
(PXA_DCMD_LENGTH & sizeof(u32));
if (flags & DMA_PREP_INTERRUPT)
updater->dcmd |= PXA_DCMD_ENDIRQEN;
if (sw_desc->cyclic)
sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr = sw_desc->first;
}
static bool is_desc_completed(struct virt_dma_desc *vd)
{
struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
struct pxad_desc_hw *updater =
sw_desc->hw_desc[sw_desc->nb_desc - 1];
return updater->dtadr != (updater->dsadr + 8);
}
static void pxad_desc_chain(struct virt_dma_desc *vd1,
struct virt_dma_desc *vd2)
{
struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
dma_addr_t dma_to_chain;
dma_to_chain = desc2->first;
desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
}
static bool pxad_try_hotchain(struct virt_dma_chan *vc,
struct virt_dma_desc *vd)
{
struct virt_dma_desc *vd_last_issued = NULL;
struct pxad_chan *chan = to_pxad_chan(&vc->chan);
/*
* Attempt to hot chain the tx if the phy is still running. This is
* considered successful only if either the channel is still running
* after the chaining, or if the chained transfer is completed after
* having been hot chained.
* A change of alignment is not allowed, and forbids hotchaining.
*/
if (is_chan_running(chan)) {
BUG_ON(list_empty(&vc->desc_issued));
if (!is_running_chan_misaligned(chan) &&
to_pxad_sw_desc(vd)->misaligned)
return false;
vd_last_issued = list_entry(vc->desc_issued.prev,
struct virt_dma_desc, node);
pxad_desc_chain(vd_last_issued, vd);
if (is_chan_running(chan) || is_desc_completed(vd_last_issued))
return true;
}
return false;
}
static unsigned int clear_chan_irq(struct pxad_phy *phy)
{
u32 dcsr;
u32 dint = readl(phy->base + DINT);
if (!(dint & BIT(phy->idx)))
return PXA_DCSR_RUN;
/* clear irq */
dcsr = phy_readl_relaxed(phy, DCSR);
phy_writel(phy, dcsr, DCSR);
if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
dev_warn(&phy->vchan->vc.chan.dev->device,
"%s(chan=%p): PXA_DCSR_BUSERR\n",
__func__, &phy->vchan);
return dcsr & ~PXA_DCSR_RUN;
}
static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
{
struct pxad_phy *phy = dev_id;
struct pxad_chan *chan = phy->vchan;
struct virt_dma_desc *vd, *tmp;
unsigned int dcsr;
unsigned long flags;
dma_cookie_t last_started = 0;
BUG_ON(!chan);
dcsr = clear_chan_irq(phy);
if (dcsr & PXA_DCSR_RUN)
return IRQ_NONE;
spin_lock_irqsave(&chan->vc.lock, flags);
list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
dev_dbg(&chan->vc.chan.dev->device,
"%s(): checking txd %p[%x]: completed=%d\n",
__func__, vd, vd->tx.cookie, is_desc_completed(vd));
last_started = vd->tx.cookie;
if (to_pxad_sw_desc(vd)->cyclic) {
vchan_cyclic_callback(vd);
break;
}
if (is_desc_completed(vd)) {
list_del(&vd->node);
vchan_cookie_complete(vd);
} else {
break;
}
}
if (dcsr & PXA_DCSR_BUSERR) {
chan->bus_error = last_started;
phy_disable(phy);
}
if (!chan->bus_error && dcsr & PXA_DCSR_STOPSTATE) {
dev_dbg(&chan->vc.chan.dev->device,
"%s(): channel stopped, submitted_empty=%d issued_empty=%d",
__func__,
list_empty(&chan->vc.desc_submitted),
list_empty(&chan->vc.desc_issued));
phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
if (list_empty(&chan->vc.desc_issued)) {
chan->misaligned =
!list_empty(&chan->vc.desc_submitted);
} else {
vd = list_first_entry(&chan->vc.desc_issued,
struct virt_dma_desc, node);
pxad_launch_chan(chan, to_pxad_sw_desc(vd));
}
}
spin_unlock_irqrestore(&chan->vc.lock, flags);
return IRQ_HANDLED;
}
static irqreturn_t pxad_int_handler(int irq, void *dev_id)
{
struct pxad_device *pdev = dev_id;
struct pxad_phy *phy;
u32 dint = readl(pdev->base + DINT);
int i, ret = IRQ_NONE;
while (dint) {
i = __ffs(dint);
dint &= (dint - 1);
phy = &pdev->phys[i];
if ((i < 32) && (legacy_reserved & BIT(i)))
continue;
if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
ret = IRQ_HANDLED;
}
return ret;
}
static int pxad_alloc_chan_resources(struct dma_chan *dchan)
{
struct pxad_chan *chan = to_pxad_chan(dchan);
struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
if (chan->desc_pool)
return 1;
chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
pdev->slave.dev,
sizeof(struct pxad_desc_hw),
__alignof__(struct pxad_desc_hw),
0);
if (!chan->desc_pool) {
dev_err(&chan->vc.chan.dev->device,
"%s(): unable to allocate descriptor pool\n",
__func__);
return -ENOMEM;
}
return 1;
}
static void pxad_free_chan_resources(struct dma_chan *dchan)
{
struct pxad_chan *chan = to_pxad_chan(dchan);
vchan_free_chan_resources(&chan->vc);
dma_pool_destroy(chan->desc_pool);
chan->desc_pool = NULL;
}
static void pxad_free_desc(struct virt_dma_desc *vd)
{
int i;
dma_addr_t dma;
struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
BUG_ON(sw_desc->nb_desc == 0);
for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
if (i > 0)
dma = sw_desc->hw_desc[i - 1]->ddadr;
else
dma = sw_desc->first;
dma_pool_free(sw_desc->desc_pool,
sw_desc->hw_desc[i], dma);
}
sw_desc->nb_desc = 0;
kfree(sw_desc);
}
static struct pxad_desc_sw *
pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
{
struct pxad_desc_sw *sw_desc;
dma_addr_t dma;
int i;
sw_desc = kzalloc(sizeof(*sw_desc) +
nb_hw_desc * sizeof(struct pxad_desc_hw *),
GFP_NOWAIT);
if (!sw_desc)
return NULL;
sw_desc->desc_pool = chan->desc_pool;
for (i = 0; i < nb_hw_desc; i++) {
sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
GFP_NOWAIT, &dma);
if (!sw_desc->hw_desc[i]) {
dev_err(&chan->vc.chan.dev->device,
"%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
__func__, i, sw_desc->desc_pool);
goto err;
}
if (i == 0)
sw_desc->first = dma;
else
sw_desc->hw_desc[i - 1]->ddadr = dma;
sw_desc->nb_desc++;
}
return sw_desc;
err:
pxad_free_desc(&sw_desc->vd);
return NULL;
}
static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct virt_dma_chan *vc = to_virt_chan(tx->chan);
struct pxad_chan *chan = to_pxad_chan(&vc->chan);
struct virt_dma_desc *vd_chained = NULL,
*vd = container_of(tx, struct virt_dma_desc, tx);
dma_cookie_t cookie;
unsigned long flags;
set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
spin_lock_irqsave(&vc->lock, flags);
cookie = dma_cookie_assign(tx);
if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
list_move_tail(&vd->node, &vc->desc_issued);
dev_dbg(&chan->vc.chan.dev->device,
"%s(): txd %p[%x]: submitted (hot linked)\n",
__func__, vd, cookie);
goto out;
}
/*
* Fallback to placing the tx in the submitted queue
*/
if (!list_empty(&vc->desc_submitted)) {
vd_chained = list_entry(vc->desc_submitted.prev,
struct virt_dma_desc, node);
/*
* Only chain the descriptors if no new misalignment is
* introduced. If a new misalignment is chained, let the channel
* stop, and be relaunched in misalign mode from the irq
* handler.
*/
if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
pxad_desc_chain(vd_chained, vd);
else
vd_chained = NULL;
}
dev_dbg(&chan->vc.chan.dev->device,
"%s(): txd %p[%x]: submitted (%s linked)\n",
__func__, vd, cookie, vd_chained ? "cold" : "not");
list_move_tail(&vd->node, &vc->desc_submitted);
chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
out:
spin_unlock_irqrestore(&vc->lock, flags);
return cookie;
}
static void pxad_issue_pending(struct dma_chan *dchan)
{
struct pxad_chan *chan = to_pxad_chan(dchan);
struct virt_dma_desc *vd_first;
unsigned long flags;
spin_lock_irqsave(&chan->vc.lock, flags);
if (list_empty(&chan->vc.desc_submitted))
goto out;
vd_first = list_first_entry(&chan->vc.desc_submitted,
struct virt_dma_desc, node);
dev_dbg(&chan->vc.chan.dev->device,
"%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
vchan_issue_pending(&chan->vc);
if (!pxad_try_hotchain(&chan->vc, vd_first))
pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
out:
spin_unlock_irqrestore(&chan->vc.lock, flags);
}
static inline struct dma_async_tx_descriptor *
pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
unsigned long tx_flags)
{
struct dma_async_tx_descriptor *tx;
struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
INIT_LIST_HEAD(&vd->node);
tx = vchan_tx_prep(vc, vd, tx_flags);
tx->tx_submit = pxad_tx_submit;
dev_dbg(&chan->vc.chan.dev->device,
"%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
vc, vd, vd->tx.cookie,
tx_flags);
return tx;
}
static void pxad_get_config(struct pxad_chan *chan,
enum dma_transfer_direction dir,
u32 *dcmd, u32 *dev_src, u32 *dev_dst)
{
u32 maxburst = 0, dev_addr = 0;
enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
*dcmd = 0;
if (dir == DMA_DEV_TO_MEM) {
maxburst = chan->cfg.src_maxburst;
width = chan->cfg.src_addr_width;
dev_addr = chan->cfg.src_addr;
*dev_src = dev_addr;
*dcmd |= PXA_DCMD_INCTRGADDR;
if (chan->drcmr <= pdev->nr_requestors)
*dcmd |= PXA_DCMD_FLOWSRC;
}
if (dir == DMA_MEM_TO_DEV) {
maxburst = chan->cfg.dst_maxburst;
width = chan->cfg.dst_addr_width;
dev_addr = chan->cfg.dst_addr;
*dev_dst = dev_addr;
*dcmd |= PXA_DCMD_INCSRCADDR;
if (chan->drcmr <= pdev->nr_requestors)
*dcmd |= PXA_DCMD_FLOWTRG;
}
if (dir == DMA_MEM_TO_MEM)
*dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
PXA_DCMD_INCSRCADDR;
dev_dbg(&chan->vc.chan.dev->device,
"%s(): dev_addr=0x%x maxburst=%d width=%d dir=%d\n",
__func__, dev_addr, maxburst, width, dir);
if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
*dcmd |= PXA_DCMD_WIDTH1;
else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
*dcmd |= PXA_DCMD_WIDTH2;
else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
*dcmd |= PXA_DCMD_WIDTH4;
if (maxburst == 8)
*dcmd |= PXA_DCMD_BURST8;
else if (maxburst == 16)
*dcmd |= PXA_DCMD_BURST16;
else if (maxburst == 32)
*dcmd |= PXA_DCMD_BURST32;
/* FIXME: drivers should be ported over to use the filter
* function. Once that's done, the following two lines can
* be removed.
*/
if (chan->cfg.slave_id)
chan->drcmr = chan->cfg.slave_id;
}
static struct dma_async_tx_descriptor *
pxad_prep_memcpy(struct dma_chan *dchan,
dma_addr_t dma_dst, dma_addr_t dma_src,
size_t len, unsigned long flags)
{
struct pxad_chan *chan = to_pxad_chan(dchan);
struct pxad_desc_sw *sw_desc;
struct pxad_desc_hw *hw_desc;
u32 dcmd;
unsigned int i, nb_desc = 0;
size_t copy;
if (!dchan || !len)
return NULL;
dev_dbg(&chan->vc.chan.dev->device,
"%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
__func__, (unsigned long)dma_dst, (unsigned long)dma_src,
len, flags);
pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);