Skip to content

Commit

Permalink
net: smc911x: convert pxa dma to dmaengine
Browse files Browse the repository at this point in the history 
Convert the dma transfers to be dmaengine based, now pxa has a dmaengine
slave driver. This makes this driver a bit more PXA agnostic.

The driver was only compile tested. The risk is quite small as no
current PXA platform I'm aware of is using smc911x driver.

Signed-off-by: Robert Jarzmik <[email protected]>
Tested-by: Fabio Estevam <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
  • Loading branch information
@rjarzmik @davem330
rjarzmik authored and davem330 committed Mar 19, 2016
1 parent c9d0bc5 commit 79d3b59
Show file tree
Hide file tree
Showing 2 changed files with 82 additions and 66 deletions.
85 changes: 56 additions & 29 deletions drivers/net/ethernet/smsc/smc911x.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -73,6 +73,9 @@ static const char version[] =
#include <linux/etherdevice.h>
#include <linux/skbuff.h>

#include <linux/dmaengine.h>
#include <linux/dma/pxa-dma.h>

#include <asm/io.h>

#include "smc911x.h"
Expand Down Expand Up @@ -1174,18 +1177,16 @@ static irqreturn_t smc911x_interrupt(int irq, void *dev_id)

#ifdef SMC_USE_DMA
static void
smc911x_tx_dma_irq(int dma, void *data)
smc911x_tx_dma_irq(void *data)
{
struct net_device *dev = (struct net_device *)data;
struct smc911x_local *lp = netdev_priv(dev);
struct smc911x_local *lp = data;
struct net_device *dev = lp->netdev;
struct sk_buff *skb = lp->current_tx_skb;
unsigned long flags;

DBG(SMC_DEBUG_FUNC, dev, "--> %s\n", __func__);

DBG(SMC_DEBUG_TX | SMC_DEBUG_DMA, dev, "TX DMA irq handler\n");
/* Clear the DMA interrupt sources */
SMC_DMA_ACK_IRQ(dev, dma);
BUG_ON(skb == NULL);
dma_unmap_single(NULL, tx_dmabuf, tx_dmalen, DMA_TO_DEVICE);
dev->trans_start = jiffies;
Expand All @@ -1208,18 +1209,16 @@ smc911x_tx_dma_irq(int dma, void *data)
"TX DMA irq completed\n");
}
static void
smc911x_rx_dma_irq(int dma, void *data)
smc911x_rx_dma_irq(void *data)
{
struct net_device *dev = (struct net_device *)data;
struct smc911x_local *lp = netdev_priv(dev);
struct smc911x_local *lp = data;
struct net_device *dev = lp->netdev;
struct sk_buff *skb = lp->current_rx_skb;
unsigned long flags;
unsigned int pkts;

DBG(SMC_DEBUG_FUNC, dev, "--> %s\n", __func__);
DBG(SMC_DEBUG_RX | SMC_DEBUG_DMA, dev, "RX DMA irq handler\n");
/* Clear the DMA interrupt sources */
SMC_DMA_ACK_IRQ(dev, dma);
dma_unmap_single(NULL, rx_dmabuf, rx_dmalen, DMA_FROM_DEVICE);
BUG_ON(skb == NULL);
lp->current_rx_skb = NULL;
Expand Down Expand Up @@ -1792,6 +1791,9 @@ static int smc911x_probe(struct net_device *dev)
unsigned int val, chip_id, revision;
const char *version_string;
unsigned long irq_flags;
struct dma_slave_config config;
dma_cap_mask_t mask;
struct pxad_param param;

DBG(SMC_DEBUG_FUNC, dev, "--> %s\n", __func__);

Expand Down Expand Up @@ -1963,11 +1965,40 @@ static int smc911x_probe(struct net_device *dev)
goto err_out;

#ifdef SMC_USE_DMA
lp->rxdma = SMC_DMA_REQUEST(dev, smc911x_rx_dma_irq);
lp->txdma = SMC_DMA_REQUEST(dev, smc911x_tx_dma_irq);

dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
param.prio = PXAD_PRIO_LOWEST;
param.drcmr = -1UL;

lp->rxdma =
dma_request_slave_channel_compat(mask, pxad_filter_fn,
&param, &dev->dev, "rx");
lp->txdma =
dma_request_slave_channel_compat(mask, pxad_filter_fn,
&param, &dev->dev, "tx");
lp->rxdma_active = 0;
lp->txdma_active = 0;
dev->dma = lp->rxdma;

memset(&config, 0, sizeof(config));
config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
config.src_addr = lp->physaddr + RX_DATA_FIFO;
config.dst_addr = lp->physaddr + TX_DATA_FIFO;
config.src_maxburst = 32;
config.dst_maxburst = 32;
retval = dmaengine_slave_config(lp->rxdma, &config);
if (retval) {
dev_err(lp->dev, "dma rx channel configuration failed: %d\n",
retval);
goto err_out;
}
retval = dmaengine_slave_config(lp->txdma, &config);
if (retval) {
dev_err(lp->dev, "dma tx channel configuration failed: %d\n",
retval);
goto err_out;
}
#endif

retval = register_netdev(dev);
Expand All @@ -1978,11 +2009,11 @@ static int smc911x_probe(struct net_device *dev)
dev->base_addr, dev->irq);

#ifdef SMC_USE_DMA
if (lp->rxdma != -1)
pr_cont(" RXDMA %d", lp->rxdma);
if (lp->rxdma)
pr_cont(" RXDMA %p", lp->rxdma);

if (lp->txdma != -1)
pr_cont(" TXDMA %d", lp->txdma);
if (lp->txdma)
pr_cont(" TXDMA %p", lp->txdma);
#endif
pr_cont("\n");
if (!is_valid_ether_addr(dev->dev_addr)) {
Expand All @@ -2005,12 +2036,10 @@ static int smc911x_probe(struct net_device *dev)
err_out:
#ifdef SMC_USE_DMA
if (retval) {
if (lp->rxdma != -1) {
SMC_DMA_FREE(dev, lp->rxdma);
}
if (lp->txdma != -1) {
SMC_DMA_FREE(dev, lp->txdma);
}
if (lp->rxdma)
dma_release_channel(lp->rxdma);
if (lp->txdma)
dma_release_channel(lp->txdma);
}
#endif
return retval;
Expand Down Expand Up @@ -2112,12 +2141,10 @@ static int smc911x_drv_remove(struct platform_device *pdev)

#ifdef SMC_USE_DMA
{
if (lp->rxdma != -1) {
SMC_DMA_FREE(dev, lp->rxdma);
}
if (lp->txdma != -1) {
SMC_DMA_FREE(dev, lp->txdma);
}
if (lp->rxdma)
dma_release_channel(lp->rxdma);
if (lp->txdma)
dma_release_channel(lp->txdma);
}
#endif
iounmap(lp->base);
Expand Down
63 changes: 26 additions & 37 deletions drivers/net/ethernet/smsc/smc911x.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -101,8 +101,8 @@ struct smc911x_local {
#ifdef SMC_USE_DMA
/* DMA needs the physical address of the chip */
u_long physaddr;
int rxdma;
int txdma;
struct dma_chan *rxdma;
struct dma_chan *txdma;
int rxdma_active;
int txdma_active;
struct sk_buff *current_rx_skb;
Expand Down Expand Up @@ -210,34 +210,15 @@ static inline void SMC_outsl(struct smc911x_local *lp, int reg,

#ifdef SMC_USE_PXA_DMA

#include <mach/dma.h>

/*
* Define the request and free functions
* These are unfortunately architecture specific as no generic allocation
* mechanism exits
*/
#define SMC_DMA_REQUEST(dev, handler) \
pxa_request_dma(dev->name, DMA_PRIO_LOW, handler, dev)

#define SMC_DMA_FREE(dev, dma) \
pxa_free_dma(dma)

#define SMC_DMA_ACK_IRQ(dev, dma) \
{ \
if (DCSR(dma) & DCSR_BUSERR) { \
netdev_err(dev, "DMA %d bus error!\n", dma); \
} \
DCSR(dma) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; \
}

/*
* Use a DMA for RX and TX packets.
*/
#include <linux/dma-mapping.h>

static dma_addr_t rx_dmabuf, tx_dmabuf;
static int rx_dmalen, tx_dmalen;
static void smc911x_rx_dma_irq(void *data);
static void smc911x_tx_dma_irq(void *data);

#ifdef SMC_insl
#undef SMC_insl
Expand All @@ -246,8 +227,10 @@ static int rx_dmalen, tx_dmalen;

static inline void
smc_pxa_dma_insl(struct smc911x_local *lp, u_long physaddr,
int reg, int dma, u_char *buf, int len)
int reg, struct dma_chan *dma, u_char *buf, int len)
{
struct dma_async_tx_descriptor *tx;

/* 64 bit alignment is required for memory to memory DMA */
if ((long)buf & 4) {
*((u32 *)buf) = SMC_inl(lp, reg);
Expand All @@ -258,12 +241,14 @@ smc_pxa_dma_insl(struct smc911x_local *lp, u_long physaddr,
len *= 4;
rx_dmabuf = dma_map_single(lp->dev, buf, len, DMA_FROM_DEVICE);
rx_dmalen = len;
DCSR(dma) = DCSR_NODESC;
DTADR(dma) = rx_dmabuf;
DSADR(dma) = physaddr + reg;
DCMD(dma) = (DCMD_INCTRGADDR | DCMD_BURST32 |
DCMD_WIDTH4 | DCMD_ENDIRQEN | (DCMD_LENGTH & rx_dmalen));
DCSR(dma) = DCSR_NODESC | DCSR_RUN;
tx = dmaengine_prep_slave_single(dma, rx_dmabuf, rx_dmalen,
DMA_DEV_TO_MEM, 0);
if (tx) {
tx->callback = smc911x_rx_dma_irq;
tx->callback_param = lp;
dmaengine_submit(tx);
dma_async_issue_pending(dma);
}
}
#endif

Expand All @@ -274,8 +259,10 @@ smc_pxa_dma_insl(struct smc911x_local *lp, u_long physaddr,

static inline void
smc_pxa_dma_outsl(struct smc911x_local *lp, u_long physaddr,
int reg, int dma, u_char *buf, int len)
int reg, struct dma_chan *dma, u_char *buf, int len)
{
struct dma_async_tx_descriptor *tx;

/* 64 bit alignment is required for memory to memory DMA */
if ((long)buf & 4) {
SMC_outl(*((u32 *)buf), lp, reg);
Expand All @@ -286,12 +273,14 @@ smc_pxa_dma_outsl(struct smc911x_local *lp, u_long physaddr,
len *= 4;
tx_dmabuf = dma_map_single(lp->dev, buf, len, DMA_TO_DEVICE);
tx_dmalen = len;
DCSR(dma) = DCSR_NODESC;
DSADR(dma) = tx_dmabuf;
DTADR(dma) = physaddr + reg;
DCMD(dma) = (DCMD_INCSRCADDR | DCMD_BURST32 |
DCMD_WIDTH4 | DCMD_ENDIRQEN | (DCMD_LENGTH & tx_dmalen));
DCSR(dma) = DCSR_NODESC | DCSR_RUN;
tx = dmaengine_prep_slave_single(dma, tx_dmabuf, tx_dmalen,
DMA_DEV_TO_MEM, 0);
if (tx) {
tx->callback = smc911x_tx_dma_irq;
tx->callback_param = lp;
dmaengine_submit(tx);
dma_async_issue_pending(dma);
}
}
#endif
#endif /* SMC_USE_PXA_DMA */
Expand Down

0 comments on commit 79d3b59

Please sign in to comment.