rtems/rtems-libbsd
1
0
Fork 0
mirror of https://git.rtems.org/rtems-libbsd/ synced 2025-10-15 22:56:40 +08:00
Code Issues Packages Projects Releases Wiki Activity

if_dwc: Avoid tx defrag if possible

Browse Source 
Drop packets in case of resource shortage.
This commit is contained in:
Sebastian Huber
2015-03-27 14:16:40 +01:00
parent d9ff8281d7
commit 5deeb69c7e
2 changed files with 90 additions and 56 deletions
Download Patch File Download Diff File Expand all files Collapse all files

133
freebsd/sys/dev/dwc/if_dwc.c
View File

@@ -157,10 +157,10 @@ next_rxidx(struct dwc_softc *sc, uint32_t curidx)
} }
static inline uint32_t static inline uint32_t
next_txidx(struct dwc_softc *sc, uint32_t curidx) next_txidx(struct dwc_softc *sc, uint32_t curidx, int inc)
{ {
return ((curidx + 1) % TX_DESC_COUNT); return ((curidx + (uint32_t)inc) % TX_DESC_COUNT);
} }
static void static void
@@ -172,62 +172,100 @@ dwc_get1paddr(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
*(bus_addr_t *)arg = segs[0].ds_addr; *(bus_addr_t *)arg = segs[0].ds_addr;
} }
inline static uint32_t static void
dwc_setup_txdesc(struct dwc_softc *sc, int idx, bus_addr_t paddr, dwc_setup_txdesc(struct dwc_softc *sc, int idx, bus_dma_segment_t segs[TX_MAX_DMA_SEGS],
uint32_t len) int nsegs)
{ {
int i;
sc->txcount += nsegs;
idx = next_txidx(sc, idx, nsegs);
sc->tx_idx_head = idx;
/*
* Fill in the TX descriptors back to front so that OWN bit in first
* descriptor is set last.
*/
for (i = nsegs - 1; i >= 0; i--) {
uint32_t flags; uint32_t flags;
uint32_t len;
++sc->txcount; idx = next_txidx(sc, idx, -1);
sc->txdesc_ring[idx].addr = segs[i].ds_addr;
len = segs[i].ds_len;
sc->txdesc_ring[idx].addr = (uint32_t)(paddr);
if (sc->mactype == DWC_GMAC_ALT_DESC) { if (sc->mactype == DWC_GMAC_ALT_DESC) {
flags = DDESC_CNTL_TXCHAIN | DDESC_CNTL_TXFIRST flags = DDESC_CNTL_TXCHAIN | DDESC_CNTL_TXINT;
| DDESC_CNTL_TXLAST | DDESC_CNTL_TXINT;
if (i == 0)
flags |= DDESC_CNTL_TXFIRST;
if (i == nsegs - 1)
flags |= DDESC_CNTL_TXLAST;
sc->txdesc_ring[idx].tdes0 = 0; sc->txdesc_ring[idx].tdes0 = 0;
sc->txdesc_ring[idx].tdes1 = flags | len; sc->txdesc_ring[idx].tdes1 = flags | len;
} else { } else {
flags = DDESC_TDES0_TXCHAIN | DDESC_TDES0_TXFIRST flags = DDESC_TDES0_TXCHAIN | DDESC_TDES0_TXINT |
| DDESC_TDES0_TXLAST | DDESC_TDES0_TXINT; DDESC_TDES0_OWN;
sc->txdesc_ring[idx].tdes0 = flags;
if (i == 0)
flags |= DDESC_TDES0_TXFIRST;
if (i == nsegs - 1)
flags |= DDESC_TDES0_TXLAST;
sc->txdesc_ring[idx].tdes1 = len; sc->txdesc_ring[idx].tdes1 = len;
}
wmb(); wmb();
sc->txdesc_ring[idx].tdes0 = flags;
sc->txdesc_ring[idx].tdes0 = DDESC_TDES0_TXCHAIN | DDESC_TDES0_TXFIRST
| DDESC_TDES0_TXLAST | DDESC_TDES0_TXINT | DDESC_TDES0_OWN;
wmb();
return (next_txidx(sc, idx));
} }
static int wmb();
dwc_setup_txbuf(struct dwc_softc *sc, int idx, struct mbuf **mp)
if (i != 0)
sc->txbuf_map[idx].mbuf = NULL;
}
}
static void
dwc_setup_txbuf(struct dwc_softc *sc, struct mbuf *m, int *start_tx)
{ {
struct bus_dma_segment seg; bus_dma_segment_t segs[TX_MAX_DMA_SEGS];
int error, nsegs; int error, nsegs, idx;
struct mbuf * m;
if ((m = m_defrag(*mp, M_NOWAIT)) == NULL)
return (ENOMEM);
*mp = m;
idx = sc->tx_idx_head;
error = bus_dmamap_load_mbuf_sg(sc->txbuf_tag, sc->txbuf_map[idx].map, error = bus_dmamap_load_mbuf_sg(sc->txbuf_tag, sc->txbuf_map[idx].map,
m, &seg, &nsegs, 0); m, &seg, &nsegs, BUS_DMA_NOWAIT);
if (error == EFBIG) {
/* Too many segments! Defrag and try again. */
struct mbuf *m2 = m_defrag(m, M_NOWAIT);
if (m2 == NULL) {
m_freem(m);
return;
}
m = m2;
error = bus_dmamap_load_mbuf_sg(sc->txbuf_tag,
sc->txbuf_map[idx].map, m, &seg, &nsegs, BUS_DMA_NOWAIT);
}
if (error != 0) { if (error != 0) {
return (ENOMEM); /* Give up. */
m_freem(m);
return;
} }
KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs)); sc->txbuf_map[idx].mbuf = m;
bus_dmamap_sync(sc->txbuf_tag, sc->txbuf_map[idx].map, bus_dmamap_sync(sc->txbuf_tag, sc->txbuf_map[idx].map,
BUS_DMASYNC_PREWRITE); BUS_DMASYNC_PREWRITE);
sc->txbuf_map[idx].mbuf = m; dwc_setup_txdesc(sc, idx, segs, nsegs);
dwc_setup_txdesc(sc, idx, seg.ds_addr, seg.ds_len); ETHER_BPF_MTAP(sc->ifp, m);
*start_tx = 1;
return (0);
} }
static void static void
@@ -235,7 +273,7 @@ dwc_txstart_locked(struct dwc_softc *sc)
{ {
struct ifnet *ifp; struct ifnet *ifp;
struct mbuf *m; struct mbuf *m;
int enqueued; int start_tx;
DWC_ASSERT_LOCKED(sc); DWC_ASSERT_LOCKED(sc);
@@ -244,10 +282,10 @@ dwc_txstart_locked(struct dwc_softc *sc)
ifp = sc->ifp; ifp = sc->ifp;
enqueued = 0; start_tx = 0;
for (;;) { for (;;) {
if (sc->txcount == (TX_DESC_COUNT-1)) { if (sc->txcount >= (TX_DESC_COUNT - 1 - TX_MAX_DMA_SEGS)) {
ifp->if_drv_flags |= IFF_DRV_OACTIVE; ifp->if_drv_flags |= IFF_DRV_OACTIVE;
break; break;
} }
@@ -255,16 +293,11 @@ dwc_txstart_locked(struct dwc_softc *sc)
IFQ_DRV_DEQUEUE(&ifp->if_snd, m); IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
if (m == NULL) if (m == NULL)
break; break;
if (dwc_setup_txbuf(sc, sc->tx_idx_head, &m) != 0) {
IFQ_DRV_PREPEND(&ifp->if_snd, m); dwc_setup_txbuf(sc, m, &start_tx);
break;
}
BPF_MTAP(ifp, m);
sc->tx_idx_head = next_txidx(sc, sc->tx_idx_head);
++enqueued;
} }
if (enqueued != 0) { if (start_tx != 0) {
WRITE4(sc, TRANSMIT_POLL_DEMAND, 0x1); WRITE4(sc, TRANSMIT_POLL_DEMAND, 0x1);
sc->tx_watchdog_count = WATCHDOG_TIMEOUT_SECS; sc->tx_watchdog_count = WATCHDOG_TIMEOUT_SECS;
} }
@@ -475,7 +508,7 @@ dwc_setup_rxdesc(struct dwc_softc *sc, int idx, bus_addr_t paddr)
static int static int
dwc_setup_rxbuf(struct dwc_softc *sc, int idx, struct mbuf *m) dwc_setup_rxbuf(struct dwc_softc *sc, int idx, struct mbuf *m)
{ {
struct bus_dma_segment seg; bus_dma_segment_t seg;
int error, nsegs; int error, nsegs;
m_adj(m, ETHER_ALIGN); m_adj(m, ETHER_ALIGN);
@@ -717,7 +750,7 @@ dwc_txfinish_locked(struct dwc_softc *sc)
m_freem(bmap->mbuf); m_freem(bmap->mbuf);
bmap->mbuf = NULL; bmap->mbuf = NULL;
--sc->txcount; --sc->txcount;
sc->tx_idx_tail = next_txidx(sc, sc->tx_idx_tail); sc->tx_idx_tail = next_txidx(sc, sc->tx_idx_tail, 1);
} }
sc->ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; sc->ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
@@ -876,7 +909,7 @@ setup_dma(struct dwc_softc *sc)
sc->txdesc_ring[idx].tdes0 = DDESC_TDES0_TXCHAIN; sc->txdesc_ring[idx].tdes0 = DDESC_TDES0_TXCHAIN;
sc->txdesc_ring[idx].tdes1 = 0; sc->txdesc_ring[idx].tdes1 = 0;
} }
nidx = next_txidx(sc, idx); nidx = next_txidx(sc, idx, 1);
sc->txdesc_ring[idx].addr_next = sc->txdesc_ring_paddr + sc->txdesc_ring[idx].addr_next = sc->txdesc_ring_paddr +
(nidx * sizeof(struct dwc_hwdesc)); (nidx * sizeof(struct dwc_hwdesc));
} }
@@ -887,7 +920,7 @@ setup_dma(struct dwc_softc *sc)
BUS_SPACE_MAXADDR_32BIT, /* lowaddr */ BUS_SPACE_MAXADDR_32BIT, /* lowaddr */
BUS_SPACE_MAXADDR, /* highaddr */ BUS_SPACE_MAXADDR, /* highaddr */
NULL, NULL, /* filter, filterarg */ NULL, NULL, /* filter, filterarg */
MCLBYTES, 1, /* maxsize, nsegments */ MCLBYTES, TX_MAX_DMA_SEGS, /* maxsize, nsegments */
MCLBYTES, /* maxsegsize */ MCLBYTES, /* maxsegsize */
0, /* flags */ 0, /* flags */
NULL, NULL, /* lockfunc, lockarg */ NULL, NULL, /* lockfunc, lockarg */

1
freebsd/sys/dev/dwc/if_dwcvar.h
View File

@@ -49,6 +49,7 @@
#define RX_DESC_SIZE (sizeof(struct dwc_hwdesc) * RX_DESC_COUNT) #define RX_DESC_SIZE (sizeof(struct dwc_hwdesc) * RX_DESC_COUNT)
#define TX_DESC_COUNT 1024 #define TX_DESC_COUNT 1024
#define TX_DESC_SIZE (sizeof(struct dwc_hwdesc) * TX_DESC_COUNT) #define TX_DESC_SIZE (sizeof(struct dwc_hwdesc) * TX_DESC_COUNT)
#define TX_MAX_DMA_SEGS 8 /* maximum segs in a tx mbuf dma */
struct dwc_bufmap { struct dwc_bufmap {
bus_dmamap_t map; bus_dmamap_t map;