spidernet: separate hardware state from driver state.
This patch separates the hardware descriptor state from the
driver descriptor state, per (old) suggestion from Ben Herrenschmidt.
This compiles and boots and seems to work.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Cc: Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
Cc: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index e4a9bdd..10f9e29 100644
--- a/drivers/net/spider_net.c
+++ b/drivers/net/spider_net.c
@@ -299,9 +299,9 @@
* returns the status as in the dmac_cmd_status field of the descriptor
*/
static inline int
-spider_net_get_descr_status(struct spider_net_descr *descr)
+spider_net_get_descr_status(struct spider_net_hw_descr *hwdescr)
{
- return descr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
+ return hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
}
/**
@@ -319,12 +319,12 @@
descr = chain->ring;
do {
descr->bus_addr = 0;
- descr->next_descr_addr = 0;
+ descr->hwdescr->next_descr_addr = 0;
descr = descr->next;
} while (descr != chain->ring);
dma_free_coherent(&card->pdev->dev, chain->num_desc,
- chain->ring, chain->dma_addr);
+ chain->hwring, chain->dma_addr);
}
/**
@@ -343,31 +343,34 @@
{
int i;
struct spider_net_descr *descr;
+ struct spider_net_hw_descr *hwdescr;
dma_addr_t buf;
size_t alloc_size;
- alloc_size = chain->num_desc * sizeof (struct spider_net_descr);
+ alloc_size = chain->num_desc * sizeof(struct spider_net_hw_descr);
- chain->ring = dma_alloc_coherent(&card->pdev->dev, alloc_size,
+ chain->hwring = dma_alloc_coherent(&card->pdev->dev, alloc_size,
&chain->dma_addr, GFP_KERNEL);
- if (!chain->ring)
+ if (!chain->hwring)
return -ENOMEM;
- descr = chain->ring;
- memset(descr, 0, alloc_size);
+ memset(chain->ring, 0, chain->num_desc * sizeof(struct spider_net_descr));
/* Set up the hardware pointers in each descriptor */
+ descr = chain->ring;
+ hwdescr = chain->hwring;
buf = chain->dma_addr;
- for (i=0; i < chain->num_desc; i++, descr++) {
- descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+ for (i=0; i < chain->num_desc; i++, descr++, hwdescr++) {
+ hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+ hwdescr->next_descr_addr = 0;
+ descr->hwdescr = hwdescr;
descr->bus_addr = buf;
- descr->next_descr_addr = 0;
descr->next = descr + 1;
descr->prev = descr - 1;
- buf += sizeof(struct spider_net_descr);
+ buf += sizeof(struct spider_net_hw_descr);
}
/* do actual circular list */
(descr-1)->next = chain->ring;
@@ -394,7 +397,7 @@
do {
if (descr->skb) {
dev_kfree_skb(descr->skb);
- pci_unmap_single(card->pdev, descr->buf_addr,
+ pci_unmap_single(card->pdev, descr->hwdescr->buf_addr,
SPIDER_NET_MAX_FRAME,
PCI_DMA_BIDIRECTIONAL);
}
@@ -416,6 +419,7 @@
spider_net_prepare_rx_descr(struct spider_net_card *card,
struct spider_net_descr *descr)
{
+ struct spider_net_hw_descr *hwdescr = descr->hwdescr;
dma_addr_t buf;
int offset;
int bufsize;
@@ -434,11 +438,11 @@
card->spider_stats.alloc_rx_skb_error++;
return -ENOMEM;
}
- descr->buf_size = bufsize;
- descr->result_size = 0;
- descr->valid_size = 0;
- descr->data_status = 0;
- descr->data_error = 0;
+ hwdescr->buf_size = bufsize;
+ hwdescr->result_size = 0;
+ hwdescr->valid_size = 0;
+ hwdescr->data_status = 0;
+ hwdescr->data_error = 0;
offset = ((unsigned long)descr->skb->data) &
(SPIDER_NET_RXBUF_ALIGN - 1);
@@ -447,21 +451,21 @@
/* iommu-map the skb */
buf = pci_map_single(card->pdev, descr->skb->data,
SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
- descr->buf_addr = buf;
if (pci_dma_mapping_error(buf)) {
dev_kfree_skb_any(descr->skb);
if (netif_msg_rx_err(card) && net_ratelimit())
pr_err("Could not iommu-map rx buffer\n");
card->spider_stats.rx_iommu_map_error++;
- descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+ hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
} else {
- descr->next_descr_addr = 0;
+ hwdescr->buf_addr = buf;
+ hwdescr->next_descr_addr = 0;
wmb();
- descr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
+ hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
SPIDER_NET_DMAC_NOINTR_COMPLETE;
wmb();
- descr->prev->next_descr_addr = descr->bus_addr;
+ descr->prev->hwdescr->next_descr_addr = descr->bus_addr;
}
return 0;
@@ -517,7 +521,7 @@
if (!spin_trylock_irqsave(&chain->lock, flags))
return;
- while (spider_net_get_descr_status(chain->head) ==
+ while (spider_net_get_descr_status(chain->head->hwdescr) ==
SPIDER_NET_DESCR_NOT_IN_USE) {
if (spider_net_prepare_rx_descr(card, chain->head))
break;
@@ -679,6 +683,7 @@
struct sk_buff *skb)
{
struct spider_net_descr *descr;
+ struct spider_net_hw_descr *hwdescr;
dma_addr_t buf;
unsigned long flags;
@@ -693,30 +698,32 @@
spin_lock_irqsave(&card->tx_chain.lock, flags);
descr = card->tx_chain.head;
+ hwdescr = descr->hwdescr;
card->tx_chain.head = descr->next;
- descr->buf_addr = buf;
- descr->buf_size = skb->len;
- descr->next_descr_addr = 0;
descr->skb = skb;
- descr->data_status = 0;
+ hwdescr->buf_addr = buf;
+ hwdescr->buf_size = skb->len;
+ hwdescr->next_descr_addr = 0;
+ hwdescr->data_status = 0;
- descr->dmac_cmd_status =
+ hwdescr->dmac_cmd_status =
SPIDER_NET_DESCR_CARDOWNED | SPIDER_NET_DMAC_NOCS;
spin_unlock_irqrestore(&card->tx_chain.lock, flags);
if (skb->protocol == htons(ETH_P_IP))
switch (skb->nh.iph->protocol) {
case IPPROTO_TCP:
- descr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
+ hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
break;
case IPPROTO_UDP:
- descr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
+ hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
break;
}
/* Chain the bus address, so that the DMA engine finds this descr. */
- descr->prev->next_descr_addr = descr->bus_addr;
+ wmb();
+ descr->prev->hwdescr->next_descr_addr = descr->bus_addr;
card->netdev->trans_start = jiffies; /* set netdev watchdog timer */
return 0;
@@ -725,16 +732,17 @@
static int
spider_net_set_low_watermark(struct spider_net_card *card)
{
+ struct spider_net_descr *descr = card->tx_chain.tail;
+ struct spider_net_hw_descr *hwdescr;
unsigned long flags;
int status;
int cnt=0;
int i;
- struct spider_net_descr *descr = card->tx_chain.tail;
/* Measure the length of the queue. Measurement does not
* need to be precise -- does not need a lock. */
while (descr != card->tx_chain.head) {
- status = descr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
+ status = descr->hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
if (status == SPIDER_NET_DESCR_NOT_IN_USE)
break;
descr = descr->next;
@@ -753,10 +761,12 @@
/* Set the new watermark, clear the old watermark */
spin_lock_irqsave(&card->tx_chain.lock, flags);
- descr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
- if (card->low_watermark && card->low_watermark != descr)
- card->low_watermark->dmac_cmd_status =
- card->low_watermark->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
+ descr->hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
+ if (card->low_watermark && card->low_watermark != descr) {
+ hwdescr = card->low_watermark->hwdescr;
+ hwdescr->dmac_cmd_status =
+ hwdescr->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
+ }
card->low_watermark = descr;
spin_unlock_irqrestore(&card->tx_chain.lock, flags);
return cnt;
@@ -779,6 +789,7 @@
{
struct spider_net_descr_chain *chain = &card->tx_chain;
struct spider_net_descr *descr;
+ struct spider_net_hw_descr *hwdescr;
struct sk_buff *skb;
u32 buf_addr;
unsigned long flags;
@@ -787,8 +798,9 @@
while (chain->tail != chain->head) {
spin_lock_irqsave(&chain->lock, flags);
descr = chain->tail;
+ hwdescr = descr->hwdescr;
- status = spider_net_get_descr_status(descr);
+ status = spider_net_get_descr_status(hwdescr);
switch (status) {
case SPIDER_NET_DESCR_COMPLETE:
card->netdev_stats.tx_packets++;
@@ -824,9 +836,9 @@
}
chain->tail = descr->next;
- descr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
+ hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
skb = descr->skb;
- buf_addr = descr->buf_addr;
+ buf_addr = hwdescr->buf_addr;
spin_unlock_irqrestore(&chain->lock, flags);
/* unmap the skb */
@@ -862,7 +874,7 @@
descr = card->tx_chain.tail;
for (;;) {
- if (spider_net_get_descr_status(descr) ==
+ if (spider_net_get_descr_status(descr->hwdescr) ==
SPIDER_NET_DESCR_CARDOWNED) {
spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
descr->bus_addr);
@@ -958,17 +970,18 @@
spider_net_pass_skb_up(struct spider_net_descr *descr,
struct spider_net_card *card)
{
+ struct spider_net_hw_descr *hwdescr= descr->hwdescr;
struct sk_buff *skb;
struct net_device *netdev;
u32 data_status, data_error;
- data_status = descr->data_status;
- data_error = descr->data_error;
+ data_status = hwdescr->data_status;
+ data_error = hwdescr->data_error;
netdev = card->netdev;
skb = descr->skb;
skb->dev = netdev;
- skb_put(skb, descr->valid_size);
+ skb_put(skb, hwdescr->valid_size);
/* the card seems to add 2 bytes of junk in front
* of the ethernet frame */
@@ -1044,9 +1057,10 @@
{
struct spider_net_descr_chain *chain = &card->rx_chain;
struct spider_net_descr *descr = chain->tail;
+ struct spider_net_hw_descr *hwdescr = descr->hwdescr;
int status;
- status = spider_net_get_descr_status(descr);
+ status = spider_net_get_descr_status(hwdescr);
/* Nothing in the descriptor, or ring must be empty */
if ((status == SPIDER_NET_DESCR_CARDOWNED) ||
@@ -1057,7 +1071,7 @@
chain->tail = descr->next;
/* unmap descriptor */
- pci_unmap_single(card->pdev, descr->buf_addr,
+ pci_unmap_single(card->pdev, hwdescr->buf_addr,
SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
if ( (status == SPIDER_NET_DESCR_RESPONSE_ERROR) ||
@@ -1080,27 +1094,26 @@
}
/* The cases we'll throw away the packet immediately */
- if (descr->data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
+ if (hwdescr->data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
if (netif_msg_rx_err(card))
pr_err("%s: error in received descriptor found, "
"data_status=x%08x, data_error=x%08x\n",
card->netdev->name,
- descr->data_status, descr->data_error);
+ hwdescr->data_status, hwdescr->data_error);
goto bad_desc;
}
- if (descr->dmac_cmd_status & 0xfefe) {
+ if (hwdescr->dmac_cmd_status & 0xfefe) {
pr_err("%s: bad status, cmd_status=x%08x\n",
card->netdev->name,
- descr->dmac_cmd_status);
- pr_err("buf_addr=x%08x\n", descr->buf_addr);
- pr_err("buf_size=x%08x\n", descr->buf_size);
- pr_err("next_descr_addr=x%08x\n", descr->next_descr_addr);
- pr_err("result_size=x%08x\n", descr->result_size);
- pr_err("valid_size=x%08x\n", descr->valid_size);
- pr_err("data_status=x%08x\n", descr->data_status);
- pr_err("data_error=x%08x\n", descr->data_error);
- pr_err("bus_addr=x%08x\n", descr->bus_addr);
+ hwdescr->dmac_cmd_status);
+ pr_err("buf_addr=x%08x\n", hwdescr->buf_addr);
+ pr_err("buf_size=x%08x\n", hwdescr->buf_size);
+ pr_err("next_descr_addr=x%08x\n", hwdescr->next_descr_addr);
+ pr_err("result_size=x%08x\n", hwdescr->result_size);
+ pr_err("valid_size=x%08x\n", hwdescr->valid_size);
+ pr_err("data_status=x%08x\n", hwdescr->data_status);
+ pr_err("data_error=x%08x\n", hwdescr->data_error);
pr_err("which=%ld\n", descr - card->rx_chain.ring);
card->spider_stats.rx_desc_error++;
@@ -1109,12 +1122,12 @@
/* Ok, we've got a packet in descr */
spider_net_pass_skb_up(descr, card);
- descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+ hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
return 1;
bad_desc:
dev_kfree_skb_irq(descr->skb);
- descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+ hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
return 0;
}
@@ -2200,9 +2213,6 @@
card->options.rx_csum = SPIDER_NET_RX_CSUM_DEFAULT;
- card->tx_chain.num_desc = tx_descriptors;
- card->rx_chain.num_desc = rx_descriptors;
-
spider_net_setup_netdev_ops(netdev);
netdev->features = NETIF_F_HW_CSUM | NETIF_F_LLTX;
@@ -2250,8 +2260,11 @@
{
struct net_device *netdev;
struct spider_net_card *card;
+ size_t alloc_size;
- netdev = alloc_etherdev(sizeof(struct spider_net_card));
+ alloc_size = sizeof(struct spider_net_card) +
+ (tx_descriptors + rx_descriptors) * sizeof(struct spider_net_descr);
+ netdev = alloc_etherdev(alloc_size);
if (!netdev)
return NULL;
@@ -2262,6 +2275,11 @@
init_waitqueue_head(&card->waitq);
atomic_set(&card->tx_timeout_task_counter, 0);
+ card->rx_chain.num_desc = rx_descriptors;
+ card->rx_chain.ring = card->darray;
+ card->tx_chain.num_desc = tx_descriptors;
+ card->tx_chain.ring = card->darray + rx_descriptors;
+
return card;
}