Align Tx/Rx descriptors on 32 bytes boundary instead of PAGE_SIZE.

Also align setup descriptor on 32 bytes boundary. Tx buffer have no
alignment limitation so create dmamap without alignment
restriction[1]. Rx buffer still seems to require 4 bytes alignment
limitation but we can simply use MCLBYTES for size to map the
buffer instead of TULIP_DATA_PER_DESC as the buffer is allocated
with m_getcl(9).
de(4) supports up to TULIP_MAX_TXSEG segments for Tx buffers,
increase maximum dma segment size to TULIP_MAX_TXSEG * MCLBYTES.
While I'm here remove TULIP_DATA_PER_DESC as it is not used anymore.

This should fix de(4) breakage introduced after r176206.

Submitted by:	jhb [1]
Reported by:	WATANABE Kazuhiro < CQG00620 <> nifty dot ne dot jp >
Tested by:	WATANABE Kazuhiro < CQG00620 <> nifty dot ne dot jp >,
		Takahashi Yoshihiro < nyan <> jp dot freebsd dot org >

2 files changed, 8 insertions, 9 deletions

diff --git a/sys/dev/de/if_de.c b/sys/dev/de/if_de.c
index e63e4f2..c3d2839 100644
--- a/sys/dev/de/if_de.c
+++ b/sys/dev/de/if_de.c
@@ -4491,7 +4491,7 @@ tulip_busdma_freering(tulip_ringinfo_t *ri)
 /* Allocate memory for a single descriptor ring. */
 static int
 tulip_busdma_allocring(device_t dev, tulip_softc_t * const sc, size_t count,
-    bus_size_t maxsize, int nsegs, tulip_ringinfo_t *ri, const char *name)
+    bus_size_t align, int nsegs, tulip_ringinfo_t *ri, const char *name)
 {
     size_t size;
     int error, i;
@@ -4499,7 +4499,7 @@ tulip_busdma_allocring(device_t dev, tulip_softc_t * const sc, size_t count,
     /* First, setup a tag. */
     ri->ri_max = count;
     size = count * sizeof(tulip_desc_t);
-    error = bus_dma_tag_create(NULL, PAGE_SIZE, 0, BUS_SPACE_MAXADDR_32BIT,
+    error = bus_dma_tag_create(NULL, 32, 0, BUS_SPACE_MAXADDR_32BIT,
 	BUS_SPACE_MAXADDR, NULL, NULL, size, 1, size, 0, NULL, NULL,
 	&ri->ri_ring_tag);
     if (error) {
@@ -4527,9 +4527,9 @@ tulip_busdma_allocring(device_t dev, tulip_softc_t * const sc, size_t count,
     }
 
     /* Allocate a tag for the data buffers. */
-    error = bus_dma_tag_create(NULL, 4, 0,
+    error = bus_dma_tag_create(NULL, align, 0,
 	BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
-	maxsize, nsegs, TULIP_DATA_PER_DESC, 0, NULL, NULL, &ri->ri_data_tag);
+	MCLBYTES * nsegs, nsegs, MCLBYTES, 0, NULL, NULL, &ri->ri_data_tag);
     if (error) {
 	device_printf(dev, "failed to allocate %s buffer dma tag\n", name);
 	return (error);
@@ -4587,8 +4587,8 @@ tulip_busdma_init(device_t dev, tulip_softc_t * const sc)
     /*
      * Allocate space and dmamap for transmit ring.
      */
-    error = tulip_busdma_allocring(dev, sc, TULIP_TXDESCS, TULIP_DATA_PER_DESC,
-	TULIP_MAX_TXSEG, &sc->tulip_txinfo, "transmit");
+    error = tulip_busdma_allocring(dev, sc, TULIP_TXDESCS, 1, TULIP_MAX_TXSEG,
+	&sc->tulip_txinfo, "transmit");
     if (error)
 	return (error);
 
@@ -4599,7 +4599,7 @@ tulip_busdma_init(device_t dev, tulip_softc_t * const sc)
      * a waste in practice though as an ethernet frame can easily fit
      * in TULIP_RX_BUFLEN bytes.
      */
-    error = tulip_busdma_allocring(dev, sc, TULIP_RXDESCS, MCLBYTES, 1,
+    error = tulip_busdma_allocring(dev, sc, TULIP_RXDESCS, 4, 1,
 	&sc->tulip_rxinfo, "receive");
     if (error)
 	return (error);
@@ -4607,7 +4607,7 @@ tulip_busdma_init(device_t dev, tulip_softc_t * const sc)
     /*
      * Allocate a DMA tag, memory, and map for setup descriptor
      */
-    error = bus_dma_tag_create(NULL, 4, 0,
+    error = bus_dma_tag_create(NULL, 32, 0,
 	BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
 	sizeof(sc->tulip_setupdata), 1, sizeof(sc->tulip_setupdata), 0,
 	NULL, NULL, &sc->tulip_setup_tag);
diff --git a/sys/dev/de/if_devar.h b/sys/dev/de/if_devar.h
index a494dd8..b4feebc 100644
--- a/sys/dev/de/if_devar.h
+++ b/sys/dev/de/if_devar.h
@@ -135,7 +135,6 @@ typedef struct {
  * 100Mb/s cards the copying is just too much of a hit.
  */
 
-#define	TULIP_DATA_PER_DESC	2032
 #define	TULIP_TXTIMER		4
 #define	TULIP_RXDESCS		48
 #define	TULIP_TXDESCS		128