cxgb4: DB Drop Recovery for RDMA and LLD queues

recover LLD EQs for DB drop interrupts.  This includes adding a new
db_lock, a spin lock disabling BH too, used by the recovery thread and
the ring_tx_db() paths to allow db drop recovery.

Clean up initial DB avoidance code.

Add read_eq_indices() - this allows the LLD to use the PCIe mw to
efficiently read hw eq contexts.

Add cxgb4_sync_txq_pidx() - called by iw_cxgb4 to sync up the sw/hw
pidx value.

Add flush_eq_cache() and cxgb4_flush_eq_cache().  This allows iw_cxgb4
to flush the sge eq context cache before beginning db drop recovery.

Add module parameter, dbfoifo_int_thresh, to allow tuning the db
interrupt threshold value.

Add dbfifo_int_thresh to cxgb4_lld_info so iw_cxgb4 knows the threshold.

Add module parameter, dbfoifo_drain_delay, to allow tuning the amount
of time delay between DB FULL and EMPTY upcalls to iw_cxgb4.

Signed-off-by: Vipul Pandya <vipul@chelsio.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
index 5f3c0a728e18..ec2dafe8ae5b 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
@@ -51,6 +51,8 @@
 #define FW_VERSION_MINOR 1
 #define FW_VERSION_MICRO 0
 
+#define CH_WARN(adap, fmt, ...) dev_warn(adap->pdev_dev, fmt, ## __VA_ARGS__)
+
 enum {
 	MAX_NPORTS = 4,     /* max # of ports */
 	SERNUM_LEN = 24,    /* Serial # length */
@@ -64,6 +66,15 @@ enum {
 	MEM_MC
 };
 
+enum {
+	MEMWIN0_APERTURE = 65536,
+	MEMWIN0_BASE     = 0x30000,
+	MEMWIN1_APERTURE = 32768,
+	MEMWIN1_BASE     = 0x28000,
+	MEMWIN2_APERTURE = 2048,
+	MEMWIN2_BASE     = 0x1b800,
+};
+
 enum dev_master {
 	MASTER_CANT,
 	MASTER_MAY,
@@ -403,6 +414,9 @@ struct sge_txq {
 	struct tx_sw_desc *sdesc;   /* address of SW Tx descriptor ring */
 	struct sge_qstat *stat;     /* queue status entry */
 	dma_addr_t    phys_addr;    /* physical address of the ring */
+	spinlock_t db_lock;
+	int db_disabled;
+	unsigned short db_pidx;
 };
 
 struct sge_eth_txq {                /* state for an SGE Ethernet Tx queue */
@@ -475,6 +489,7 @@ struct adapter {
 	void __iomem *regs;
 	struct pci_dev *pdev;
 	struct device *pdev_dev;
+	unsigned int mbox;
 	unsigned int fn;
 	unsigned int flags;
 
@@ -607,6 +622,7 @@ irqreturn_t t4_sge_intr_msix(int irq, void *cookie);
 void t4_sge_init(struct adapter *adap);
 void t4_sge_start(struct adapter *adap);
 void t4_sge_stop(struct adapter *adap);
+extern int dbfifo_int_thresh;
 
 #define for_each_port(adapter, iter) \
 	for (iter = 0; iter < (adapter)->params.nports; ++iter)