[PATCH] spidernet: performance optimizations

Performance optimizations, changes in these areas:
  - RX and TX checksum offload
  - correct maximum MTU
  - don't use TX interrupts anymore, use a timer instead
  - remove some superfluous barriers
  - improve RX RAM full handling

From: Utz Bacher <utz.bacher@de.ibm.com>
Signed-off-by: Jens Osterkamp <jens.osterkamp@de.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 40 insertions, 31 deletions

diff --git a/drivers/net/spider_net.h b/drivers/net/spider_net.h
index 98f11ecf48fc..5922b529a048 100644
--- a/drivers/net/spider_net.h
+++ b/drivers/net/spider_net.h
@@ -33,25 +33,32 @@ extern struct ethtool_ops spider_net_ethtool_ops;
 
 extern char spider_net_driver_name[];
 
-#define SPIDER_NET_MAX_MTU                      2308
+#define SPIDER_NET_MAX_FRAME                    2312
+#define SPIDER_NET_MAX_MTU                      2294
 #define SPIDER_NET_MIN_MTU                      64
 
 #define SPIDER_NET_RXBUF_ALIGN                  128
 
-#define SPIDER_NET_RX_DESCRIPTORS_DEFAULT       64
+#define SPIDER_NET_RX_DESCRIPTORS_DEFAULT       256
 #define SPIDER_NET_RX_DESCRIPTORS_MIN           16
-#define SPIDER_NET_RX_DESCRIPTORS_MAX           256
+#define SPIDER_NET_RX_DESCRIPTORS_MAX           512
 
-#define SPIDER_NET_TX_DESCRIPTORS_DEFAULT       64
+#define SPIDER_NET_TX_DESCRIPTORS_DEFAULT       256
 #define SPIDER_NET_TX_DESCRIPTORS_MIN           16
-#define SPIDER_NET_TX_DESCRIPTORS_MAX           256
+#define SPIDER_NET_TX_DESCRIPTORS_MAX           512
+
+#define SPIDER_NET_TX_TIMER                     20
 
 #define SPIDER_NET_RX_CSUM_DEFAULT              1
 
-#define SPIDER_NET_WATCHDOG_TIMEOUT 5*HZ
-#define SPIDER_NET_NAPI_WEIGHT 64
+#define SPIDER_NET_WATCHDOG_TIMEOUT             50*HZ
+#define SPIDER_NET_NAPI_WEIGHT                  64
 
-#define SPIDER_NET_FIRMWARE_LEN         1024
+#define SPIDER_NET_FIRMWARE_SEQS        6
+#define SPIDER_NET_FIRMWARE_SEQWORDS    1024
+#define SPIDER_NET_FIRMWARE_LEN         (SPIDER_NET_FIRMWARE_SEQS * \
+                                         SPIDER_NET_FIRMWARE_SEQWORDS * \
+                                         sizeof(u32))
 #define SPIDER_NET_FIRMWARE_NAME        "spider_fw.bin"
 
 /** spider_net SMMIO registers */
@@ -142,14 +149,12 @@ extern char spider_net_driver_name[];
 /** SCONFIG registers */
 #define SPIDER_NET_SCONFIG_IOACTE       0x00002810
 
-/** hardcoded register values */
-#define SPIDER_NET_INT0_MASK_VALUE      0x3f7fe3ff
-#define SPIDER_NET_INT1_MASK_VALUE      0xffffffff
+/** interrupt mask registers */
+#define SPIDER_NET_INT0_MASK_VALUE      0x3f7fe2c7
+#define SPIDER_NET_INT1_MASK_VALUE      0xffff7ff7
 /* no MAC aborts -> auto retransmission */
-#define SPIDER_NET_INT2_MASK_VALUE      0xfffffff1
+#define SPIDER_NET_INT2_MASK_VALUE      0xffef7ff1
 
-/* clear counter when interrupt sources are cleared
-#define SPIDER_NET_FRAMENUM_VALUE       0x0001f001 */
 /* we rely on flagged descriptor interrupts */
 #define SPIDER_NET_FRAMENUM_VALUE       0x00000000
 /* set this first, then the FRAMENUM_VALUE */
@@ -168,7 +173,7 @@ extern char spider_net_driver_name[];
 #if 0
 #define SPIDER_NET_WOL_VALUE            0x00000000
 #endif
-#define SPIDER_NET_IPSECINIT_VALUE      0x00f000f8
+#define SPIDER_NET_IPSECINIT_VALUE      0x6f716f71
 
 /* pause frames: automatic, no upper retransmission count */
 /* outside loopback mode: ETOMOD signal dont matter, not connected */
@@ -318,6 +323,10 @@ enum spider_net_int2_status {
 #define SPIDER_NET_RXINT        ( (1 << SPIDER_NET_GDAFDCINT) | \
                                   (1 << SPIDER_NET_GRMFLLINT) )
 
+#define SPIDER_NET_ERRINT       ( 0xffffffff & \
+                                  (~SPIDER_NET_TXINT) & \
+                                  (~SPIDER_NET_RXINT) )
+
 #define SPIDER_NET_GPREXEC              0x80000000
 #define SPIDER_NET_GPRDAT_MASK          0x0000ffff
 
@@ -358,9 +367,6 @@ enum spider_net_int2_status {
 /* descr ready, descr is in middle of chain, get interrupt on completion */
 #define SPIDER_NET_DMAC_RX_CARDOWNED    0xa0800000
 
-/* multicast is no problem */
-#define SPIDER_NET_DATA_ERROR_MASK      0xffffbfff
-
 enum spider_net_descr_status {
         SPIDER_NET_DESCR_COMPLETE               = 0x00, /* used in rx and tx */
         SPIDER_NET_DESCR_RESPONSE_ERROR         = 0x01, /* used in rx and tx */
@@ -384,7 +390,7 @@ struct spider_net_descr {
 
         /* used in the driver */
         struct sk_buff *skb;
-        dma_addr_t bus_addr;
+        u32 bus_addr;
         struct spider_net_descr *next;
         struct spider_net_descr *prev;
 } __attribute__((aligned(32)));
@@ -396,21 +402,21 @@ struct spider_net_descr_chain {
 };
 
 /* descriptor data_status bits */
-#define SPIDER_NET_RXIPCHK              29
-#define SPIDER_NET_TCPUDPIPCHK          28
-#define SPIDER_NET_DATA_STATUS_CHK_MASK (1 << SPIDER_NET_RXIPCHK | \
-                                         1 << SPIDER_NET_TCPUDPIPCHK)
-
+#define SPIDER_NET_RX_IPCHK             29
+#define SPIDER_NET_RX_TCPCHK            28
 #define SPIDER_NET_VLAN_PACKET          21
+#define SPIDER_NET_DATA_STATUS_CKSUM_MASK ( (1 << SPIDER_NET_RX_IPCHK) | \
+                                          (1 << SPIDER_NET_RX_TCPCHK) )
 
 /* descriptor data_error bits */
-#define SPIDER_NET_RXIPCHKERR           27
-#define SPIDER_NET_RXTCPCHKERR          26
-#define SPIDER_NET_DATA_ERROR_CHK_MASK  (1 << SPIDER_NET_RXIPCHKERR | \
-                                         1 << SPIDER_NET_RXTCPCHKERR)
+#define SPIDER_NET_RX_IPCHKERR          27
+#define SPIDER_NET_RX_RXTCPCHKERR       28
+
+#define SPIDER_NET_DATA_ERR_CKSUM_MASK  (1 << SPIDER_NET_RX_IPCHKERR)
 
-/* the cases we don't pass the packet to the stack */
-#define SPIDER_NET_DESTROY_RX_FLAGS     0x70138000
+/* the cases we don't pass the packet to the stack.
+ * 701b8000 would be correct, but every packets gets that flag */
+#define SPIDER_NET_DESTROY_RX_FLAGS     0x700b8000
 
 #define SPIDER_NET_DESCR_SIZE           32
 
@@ -445,13 +451,16 @@ struct spider_net_card {
 
         struct spider_net_descr_chain tx_chain;
         struct spider_net_descr_chain rx_chain;
-        spinlock_t chain_lock;
+        atomic_t rx_chain_refill;
+        atomic_t tx_chain_release;
 
         struct net_device_stats netdev_stats;
 
         struct spider_net_options options;
 
         spinlock_t intmask_lock;
+        struct tasklet_struct rxram_full_tl;
+        struct timer_list tx_timer;
 
         struct work_struct tx_timeout_task;
         atomic_t tx_timeout_task_counter;