Re: [PATCH] net: smc911x: convert pxa dma to dmaengine

Hitoshi Mitake
2016-02-20T13:29:46Z

Hi Robert,

At Sat, 06 Feb 2016 10:05:51 +0100,
Robert Jarzmik wrote:
>
> David Miller <davem@davemloft.net> writes:
>
> > From: Robert Jarzmik <robert.jarzmik@free.fr>
> > Date: Fri, 05 Feb 2016 22:44:56 +0100
> >
> >> Apart from Alberto who answered he cannot test it by lack of hardware, the
> >> others didn't answer.
> >>
> >> So how can I move forward ? Would you want me to amend the KConfig to add a "&&
> >> !ARCH_PXA" on the "depend" line ?
> >
> > Please just keep pinging people to properly test this.
> Okay, let's have another try.
>
> Hi Guennadi, Hitoshi, Fabio,
>
> Could any of you try this patch to ensure your board is not broken please ?
> I've re-added the patch at the end of this mail for easier handling. Normally no
> code path in non-PXA board is changed, so the test should be straightforward.
>
> It's also available in : https://lkml.org/lkml/2015/11/30/768
>
> You're the maintainers of the following boards using smc911x AFAIK:
> - sh2007: Guennadi and Hitoshi

(I noticed my previous mail was bounced, so sending it again)

Really sorry, currently I don't have the board :(
Do you have a working board that can be used for testing, Guennadi?

Thanks,
Hitoshi

> - armadillo5x0: Alberto
> - imx v6 and imx v7: Fabio
>
> Cheers.
>
> --
> Robert
>
>
> ---8<---
> From: Robert Jarzmik <robert.jarzmik@free.fr>
> Subject: [PATCH] net: smc911x: convert pxa dma to dmaengine
> To: "David S. Miller" <davem@davemloft.net>
> Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Robert Jarzmik <robert.jarzmik@free.fr>
> Date: Mon, 30 Nov 2015 22:40:28 +0100 (9 weeks, 4 days, 11 hours ago)
> Message-Id: <1448919628-13273-1-git-send-email-robert.jarzmik@free.fr>
> X-Mailer: git-send-email 2.1.4
>
> 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 <robert.jarzmik@free.fr>
> ---
> drivers/net/ethernet/smsc/smc911x.c | 85 ++++++++++++++++++++++++-------------
> drivers/net/ethernet/smsc/smc911x.h | 63 ++++++++++++---------------
> 2 files changed, 82 insertions(+), 66 deletions(-)
>
> diff --git a/drivers/net/ethernet/smsc/smc911x.c b/drivers/net/ethernet/smsc/smc911x.c
> index bd64eb982e52..3f5711061432 100644
> --- a/drivers/net/ethernet/smsc/smc911x.c
> +++ b/drivers/net/ethernet/smsc/smc911x.c
> @@ -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"
> @@ -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;
> @@ -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;
> @@ -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__);
>
> @@ -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);
> @@ -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)) {
> @@ -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;
> @@ -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);
> diff --git a/drivers/net/ethernet/smsc/smc911x.h b/drivers/net/ethernet/smsc/smc911x.h
> index 04b35f55df97..fa528ea0ea51 100644
> --- a/drivers/net/ethernet/smsc/smc911x.h
> +++ b/drivers/net/ethernet/smsc/smc911x.h
> @@ -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;
> @@ -210,27 +210,6 @@ 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.
> */
> @@ -238,6 +217,8 @@ static inline void SMC_outsl(struct smc911x_local *lp, int reg,
>
> 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
> @@ -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);
> @@ -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
>
> @@ -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);
> @@ -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 */
> --
> 2.1.4
>