[PATCH 11/20] net: smc91x.c: switch to generic buf-to-buf DMA offload
Daniel Mack
zonque at gmail.com
Wed Aug 7 11:34:00 EDT 2013
Drop all PXA-DMA specific implementation details and rely on
dma_async_memcpy_buf_to_buf().
This patch is only compile-tested.
Signed-off-by: Daniel Mack <zonque at gmail.com>
---
drivers/net/ethernet/smsc/smc91x.c | 40 +++++++--------------
drivers/net/ethernet/smsc/smc91x.h | 71 ++++++++++++++------------------------
2 files changed, 38 insertions(+), 73 deletions(-)
diff --git a/drivers/net/ethernet/smsc/smc91x.c b/drivers/net/ethernet/smsc/smc91x.c
index cde13be..2d1e073 100644
--- a/drivers/net/ethernet/smsc/smc91x.c
+++ b/drivers/net/ethernet/smsc/smc91x.c
@@ -2015,17 +2015,17 @@ static int smc_probe(struct net_device *dev, void __iomem *ioaddr,
if (retval)
goto err_out;
-#ifdef CONFIG_ARCH_PXA
-# ifdef SMC_USE_PXA_DMA
- lp->cfg.flags |= SMC91X_USE_DMA;
-# endif
if (lp->cfg.flags & SMC91X_USE_DMA) {
- int dma = pxa_request_dma(dev->name, DMA_PRIO_LOW,
- smc_pxa_dma_irq, NULL);
- if (dma >= 0)
- dev->dma = dma;
+ dma_cap_mask_t mask;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+ lp->dma_channel = dma_request_channel(mask, NULL, NULL);
+
+ if (!lp->dma_channel)
+ printk("%s(): request of DMA channel failed\n",
+ __func__);
}
-#endif
retval = register_netdev(dev);
if (retval == 0) {
@@ -2034,9 +2034,6 @@ static int smc_probe(struct net_device *dev, void __iomem *ioaddr,
dev->name, version_string, revision_register & 0x0f,
lp->base, dev->irq);
- if (dev->dma != (unsigned char)-1)
- printk(" DMA %d", dev->dma);
-
printk("%s%s\n",
lp->cfg.flags & SMC91X_NOWAIT ? " [nowait]" : "",
THROTTLE_TX_PKTS ? " [throttle_tx]" : "");
@@ -2060,10 +2057,6 @@ static int smc_probe(struct net_device *dev, void __iomem *ioaddr,
}
err_out:
-#ifdef CONFIG_ARCH_PXA
- if (retval && dev->dma != (unsigned char)-1)
- pxa_free_dma(dev->dma);
-#endif
return retval;
}
@@ -2282,14 +2275,6 @@ static int smc_drv_probe(struct platform_device *pdev)
goto out_release_attrib;
}
-#ifdef CONFIG_ARCH_PXA
- {
- struct smc_local *lp = netdev_priv(ndev);
- lp->device = &pdev->dev;
- lp->physaddr = res->start;
- }
-#endif
-
ret = smc_probe(ndev, addr, irq_flags);
if (ret != 0)
goto out_iounmap;
@@ -2320,12 +2305,11 @@ static int smc_drv_remove(struct platform_device *pdev)
unregister_netdev(ndev);
+ if (lp->dma_channel)
+ dma_release_channel(lp->dma_channel);
+
free_irq(ndev->irq, ndev);
-#ifdef CONFIG_ARCH_PXA
- if (ndev->dma != (unsigned char)-1)
- pxa_free_dma(ndev->dma);
-#endif
iounmap(lp->base);
smc_release_datacs(pdev,ndev);
diff --git a/drivers/net/ethernet/smsc/smc91x.h b/drivers/net/ethernet/smsc/smc91x.h
index 370e13d..cf51366 100644
--- a/drivers/net/ethernet/smsc/smc91x.h
+++ b/drivers/net/ethernet/smsc/smc91x.h
@@ -34,6 +34,7 @@
#ifndef _SMC91X_H_
#define _SMC91X_H_
+#include <linux/dmaengine.h>
#include <linux/smc91x.h>
/*
@@ -338,11 +339,8 @@ struct smc_local {
spinlock_t lock;
-#ifdef CONFIG_ARCH_PXA
- /* DMA needs the physical address of the chip */
- u_long physaddr;
- struct device *device;
-#endif
+ struct dma_chan *dma_channel;
+
void __iomem *base;
void __iomem *datacs;
@@ -358,13 +356,29 @@ struct smc_local {
#ifdef CONFIG_ARCH_PXA
/*
- * Let's use the DMA engine on the XScale PXA2xx for RX packets. This is
+ * Let's use the generic DMA buffer-to-buffer offload mechanism. This is
* always happening in irq context so no need to worry about races. TX is
* different and probably not worth it for that reason, and not as critical
* as RX which can overrun memory and lose packets.
*/
-#include <linux/dma-mapping.h>
-#include <mach/dma.h>
+
+static void smc_dma_copy(struct smc_local *lp, void *dest, void *src,
+ unsigned int len)
+{
+ dma_cookie_t cookie;
+ cookie = dma_async_memcpy_buf_to_buf(lp->dma_channel, dest, src, len);
+
+ while (1) {
+ struct dma_tx_state state;
+ enum dma_status status;
+
+ status = dmaengine_tx_status(lp->dma_channel, cookie, &state);
+ if (status != DMA_IN_PROGRESS)
+ break;
+
+ cpu_relax();
+ }
+}
#ifdef SMC_insl
#undef SMC_insl
@@ -374,11 +388,8 @@ static inline void
smc_pxa_dma_insl(void __iomem *ioaddr, struct smc_local *lp, int reg, int dma,
u_char *buf, int len)
{
- u_long physaddr = lp->physaddr;
- dma_addr_t dmabuf;
-
/* fallback if no DMA available */
- if (dma == (unsigned char)-1) {
+ if (lp->dma_channel == NULL) {
readsl(ioaddr + reg, buf, len);
return;
}
@@ -390,18 +401,7 @@ smc_pxa_dma_insl(void __iomem *ioaddr, struct smc_local *lp, int reg, int dma,
len--;
}
- len *= 4;
- dmabuf = dma_map_single(lp->device, buf, len, DMA_FROM_DEVICE);
- DCSR(dma) = DCSR_NODESC;
- DTADR(dma) = dmabuf;
- DSADR(dma) = physaddr + reg;
- DCMD(dma) = (DCMD_INCTRGADDR | DCMD_BURST32 |
- DCMD_WIDTH4 | (DCMD_LENGTH & len));
- DCSR(dma) = DCSR_NODESC | DCSR_RUN;
- while (!(DCSR(dma) & DCSR_STOPSTATE))
- cpu_relax();
- DCSR(dma) = 0;
- dma_unmap_single(lp->device, dmabuf, len, DMA_FROM_DEVICE);
+ smc_dma_copy(lp, buf, (__u32 *) ioaddr + reg, len * 4);
}
#endif
@@ -413,11 +413,8 @@ static inline void
smc_pxa_dma_insw(void __iomem *ioaddr, struct smc_local *lp, int reg, int dma,
u_char *buf, int len)
{
- u_long physaddr = lp->physaddr;
- dma_addr_t dmabuf;
-
/* fallback if no DMA available */
- if (dma == (unsigned char)-1) {
+ if (lp->dma_channel == NULL) {
readsw(ioaddr + reg, buf, len);
return;
}
@@ -429,26 +426,10 @@ smc_pxa_dma_insw(void __iomem *ioaddr, struct smc_local *lp, int reg, int dma,
len--;
}
- len *= 2;
- dmabuf = dma_map_single(lp->device, buf, len, DMA_FROM_DEVICE);
- DCSR(dma) = DCSR_NODESC;
- DTADR(dma) = dmabuf;
- DSADR(dma) = physaddr + reg;
- DCMD(dma) = (DCMD_INCTRGADDR | DCMD_BURST32 |
- DCMD_WIDTH2 | (DCMD_LENGTH & len));
- DCSR(dma) = DCSR_NODESC | DCSR_RUN;
- while (!(DCSR(dma) & DCSR_STOPSTATE))
- cpu_relax();
- DCSR(dma) = 0;
- dma_unmap_single(lp->device, dmabuf, len, DMA_FROM_DEVICE);
+ smc_dma_copy(lp, buf, (__u32 *) ioaddr + reg, len * 2);
}
#endif
-static void
-smc_pxa_dma_irq(int dma, void *dummy)
-{
- DCSR(dma) = 0;
-}
#endif /* CONFIG_ARCH_PXA */
--
1.8.3.1
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