net: tsec: Use portable types and accessors for BDs

Currently, the buffer descriptor (BD) fields cannot be
correctly accessed by a little endian processor.  This
patch fixes the issue by making the access of BDs to be
portable among different cpu architectures.

Use portable data types for the Rx/Tx buffer descriptor
fields.  Use portable I/O accessors to insure that the
big endian BDs are correctly accessed by little endian
cpus too, and to insure proper sync with the H/W.
Removed the redundant RTXBD "volatile" type, as proper
synchronization around BD data accesses is provided by
the I/O accessors now.
The "sparse" tool was also used to verify the correctness
of these changes.

Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>

diff --git a/drivers/net/tsec.c b/drivers/net/tsec.c
index 289229a42b2759b8f7c86e03480f8d7f5b24aa59..e354fad21850be997d07b4f8459f7602647dfb56 100644 (file)
--- a/drivers/net/tsec.c
+++ b/drivers/net/tsec.c
@@ -28,13 +28,10 @@ DECLARE_GLOBAL_DATA_PTR;
 static uint rx_idx;            /* index of the current RX buffer */
 static uint tx_idx;            /* index of the current TX buffer */
 
-typedef volatile struct rtxbd {
-       txbd8_t txbd[TX_BUF_CNT];
-       rxbd8_t rxbd[PKTBUFSRX];
-} RTXBD;
-
 #ifdef __GNUC__
-static RTXBD rtx __attribute__ ((aligned(8)));
+static struct txbd8 __iomem txbd[TX_BUF_CNT] __aligned(8);
+static struct rxbd8 __iomem rxbd[PKTBUFSRX] __aligned(8);
+
 #else
 #error "rtx must be 64-bit aligned"
 #endif
@@ -275,10 +272,11 @@ void redundant_init(struct eth_device *dev)
        clrbits_be32(&regs->dmactrl, DMACTRL_GRS | DMACTRL_GTS);
 
        do {
+               uint16_t status;
                tsec_send(dev, (void *)pkt, sizeof(pkt));
 
                /* Wait for buffer to be received */
-               for (t = 0; rtx.rxbd[rx_idx].status & RXBD_EMPTY; t++) {
+               for (t = 0; in_be16(&rxbd[rx_idx].status) & RXBD_EMPTY; t++) {
                        if (t >= 10 * TOUT_LOOP) {
                                printf("%s: tsec: rx error\n", dev->name);
                                break;
@@ -288,9 +286,11 @@ void redundant_init(struct eth_device *dev)
                if (!memcmp(pkt, (void *)NetRxPackets[rx_idx], sizeof(pkt)))
                        fail = 0;
 
-               rtx.rxbd[rx_idx].length = 0;
-               rtx.rxbd[rx_idx].status =
-                   RXBD_EMPTY | (((rx_idx + 1) == PKTBUFSRX) ? RXBD_WRAP : 0);
+               out_be16(&rxbd[rx_idx].length, 0);
+               status = RXBD_EMPTY;
+               if ((rx_idx + 1) == PKTBUFSRX)
+                       status |= RXBD_WRAP;
+               out_be16(&rxbd[rx_idx].status, status);
                rx_idx = (rx_idx + 1) % PKTBUFSRX;
 
                if (in_be32(&regs->ievent) & IEVENT_BSY) {
@@ -319,9 +319,10 @@ void redundant_init(struct eth_device *dev)
  */
 static void startup_tsec(struct eth_device *dev)
 {
-       int i;
        struct tsec_private *priv = (struct tsec_private *)dev->priv;
        struct tsec __iomem *regs = priv->regs;
+       uint16_t status;
+       int i;
 
        /* reset the indices to zero */
        rx_idx = 0;
@@ -331,24 +332,26 @@ static void startup_tsec(struct eth_device *dev)
 #endif
 
        /* Point to the buffer descriptors */
-       out_be32(&regs->tbase, (unsigned int)(&rtx.txbd[tx_idx]));
-       out_be32(&regs->rbase, (unsigned int)(&rtx.rxbd[rx_idx]));
+       out_be32(&regs->tbase, (u32)&txbd[0]);
+       out_be32(&regs->rbase, (u32)&rxbd[0]);
 
        /* Initialize the Rx Buffer descriptors */
        for (i = 0; i < PKTBUFSRX; i++) {
-               rtx.rxbd[i].status = RXBD_EMPTY;
-               rtx.rxbd[i].length = 0;
-               rtx.rxbd[i].bufptr = (uint) NetRxPackets[i];
+               out_be16(&rxbd[i].status, RXBD_EMPTY);
+               out_be16(&rxbd[i].length, 0);
+               out_be32(&rxbd[i].bufptr, (u32)NetRxPackets[i]);
        }
-       rtx.rxbd[PKTBUFSRX - 1].status |= RXBD_WRAP;
+       status = in_be16(&rxbd[PKTBUFSRX - 1].status);
+       out_be16(&rxbd[PKTBUFSRX - 1].status, status | RXBD_WRAP);
 
        /* Initialize the TX Buffer Descriptors */
        for (i = 0; i < TX_BUF_CNT; i++) {
-               rtx.txbd[i].status = 0;
-               rtx.txbd[i].length = 0;
-               rtx.txbd[i].bufptr = 0;
+               out_be16(&txbd[i].status, 0);
+               out_be16(&txbd[i].length, 0);
+               out_be32(&txbd[i].bufptr, 0);
        }
-       rtx.txbd[TX_BUF_CNT - 1].status |= TXBD_WRAP;
+       status = in_be16(&txbd[TX_BUF_CNT - 1].status);
+       out_be16(&txbd[TX_BUF_CNT - 1].status, status | TXBD_WRAP);
 
 #ifdef CONFIG_SYS_FSL_ERRATUM_NMG_ETSEC129
        svr = get_svr();
@@ -372,29 +375,31 @@ static void startup_tsec(struct eth_device *dev)
  */
 static int tsec_send(struct eth_device *dev, void *packet, int length)
 {
-       int i;
-       int result = 0;
        struct tsec_private *priv = (struct tsec_private *)dev->priv;
        struct tsec __iomem *regs = priv->regs;
+       uint16_t status;
+       int result = 0;
+       int i;
 
        /* Find an empty buffer descriptor */
-       for (i = 0; rtx.txbd[tx_idx].status & TXBD_READY; i++) {
+       for (i = 0; in_be16(&txbd[tx_idx].status) & TXBD_READY; i++) {
                if (i >= TOUT_LOOP) {
                        debug("%s: tsec: tx buffers full\n", dev->name);
                        return result;
                }
        }
 
-       rtx.txbd[tx_idx].bufptr = (uint) packet;
-       rtx.txbd[tx_idx].length = length;
-       rtx.txbd[tx_idx].status |=
-           (TXBD_READY | TXBD_LAST | TXBD_CRC | TXBD_INTERRUPT);
+       out_be32(&txbd[tx_idx].bufptr, (u32)packet);
+       out_be16(&txbd[tx_idx].length, length);
+       status = in_be16(&txbd[tx_idx].status);
+       out_be16(&txbd[tx_idx].status, status |
+               (TXBD_READY | TXBD_LAST | TXBD_CRC | TXBD_INTERRUPT));
 
        /* Tell the DMA to go */
        out_be32(&regs->tstat, TSTAT_CLEAR_THALT);
 
        /* Wait for buffer to be transmitted */
-       for (i = 0; rtx.txbd[tx_idx].status & TXBD_READY; i++) {
+       for (i = 0; in_be16(&txbd[tx_idx].status) & TXBD_READY; i++) {
                if (i >= TOUT_LOOP) {
                        debug("%s: tsec: tx error\n", dev->name);
                        return result;
@@ -402,34 +407,33 @@ static int tsec_send(struct eth_device *dev, void *packet, int length)
        }
 
        tx_idx = (tx_idx + 1) % TX_BUF_CNT;
-       result = rtx.txbd[tx_idx].status & TXBD_STATS;
+       result = in_be16(&txbd[tx_idx].status) & TXBD_STATS;
 
        return result;
 }
 
 static int tsec_recv(struct eth_device *dev)
 {
-       int length;
        struct tsec_private *priv = (struct tsec_private *)dev->priv;
        struct tsec __iomem *regs = priv->regs;
 
-       while (!(rtx.rxbd[rx_idx].status & RXBD_EMPTY)) {
-
-               length = rtx.rxbd[rx_idx].length;
+       while (!(in_be16(&rxbd[rx_idx].status) & RXBD_EMPTY)) {
+               int length = in_be16(&rxbd[rx_idx].length);
+               uint16_t status = in_be16(&rxbd[rx_idx].status);
 
                /* Send the packet up if there were no errors */
-               if (!(rtx.rxbd[rx_idx].status & RXBD_STATS)) {
+               if (!(status & RXBD_STATS))
                        NetReceive(NetRxPackets[rx_idx], length - 4);
-               } else {
-                       printf("Got error %x\n",
-                              (rtx.rxbd[rx_idx].status & RXBD_STATS));
-               }
+               else
+                       printf("Got error %x\n", (status & RXBD_STATS));
 
-               rtx.rxbd[rx_idx].length = 0;
+               out_be16(&rxbd[rx_idx].length, 0);
 
+               status = RXBD_EMPTY;
                /* Set the wrap bit if this is the last element in the list */
-               rtx.rxbd[rx_idx].status =
-                   RXBD_EMPTY | (((rx_idx + 1) == PKTBUFSRX) ? RXBD_WRAP : 0);
+               if ((rx_idx + 1) == PKTBUFSRX)
+                       status |= RXBD_WRAP;
+               out_be16(&rxbd[rx_idx].status, status);
 
                rx_idx = (rx_idx + 1) % PKTBUFSRX;
        }

diff --git a/include/tsec.h b/include/tsec.h
index 6bc43ef65f5d02cce96530b00d6c1ef1378b6779..95054be5fb3f6d060534a516464ca058672e361e 100644 (file)
--- a/include/tsec.h
+++ b/include/tsec.h
@@ -198,19 +198,17 @@
 #define RXBD_TRUNCATED         0x0001
 #define RXBD_STATS             0x003f
 
-typedef struct txbd8
-{
-       ushort       status;         /* Status Fields */
-       ushort       length;         /* Buffer length */
-       uint         bufptr;         /* Buffer Pointer */
-} txbd8_t;
+struct txbd8 {
+       uint16_t     status;         /* Status Fields */
+       uint16_t     length;         /* Buffer length */
+       uint32_t     bufptr;         /* Buffer Pointer */
+};
 
-typedef struct rxbd8
-{
-       ushort       status;         /* Status Fields */
-       ushort       length;         /* Buffer Length */
-       uint         bufptr;         /* Buffer Pointer */
-} rxbd8_t;
+struct rxbd8 {
+       uint16_t     status;         /* Status Fields */
+       uint16_t     length;         /* Buffer Length */
+       uint32_t     bufptr;         /* Buffer Pointer */
+};
 
 typedef struct rmon_mib
 {