bnxt_en: Reduce memory usage when running in kdump kernel.

Skip RDMA context memory allocations, reduce to 1 ring, and disable
TPA when running in the kdump kernel.  Without this patch, the driver
fails to initialize with memory allocation errors when running in a
typical kdump kernel.

Fixes: cf6daed ("bnxt_en: Increase context memory allocations on 57500 chips for RDMA.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -6379,7 +6379,7 @@ static int bnxt_alloc_ctx_mem(struct bnxt *bp)
 	if (!ctx || (ctx->flags & BNXT_CTX_FLAG_INITED))
 		return 0;
 
-	if (bp->flags & BNXT_FLAG_ROCE_CAP) {
+	if ((bp->flags & BNXT_FLAG_ROCE_CAP) && !is_kdump_kernel()) {
 		pg_lvl = 2;
 		extra_qps = 65536;
 		extra_srqs = 8192;
@@ -10437,7 +10437,7 @@ static int bnxt_set_dflt_rings(struct bnxt *bp, bool sh)
 
 	if (sh)
 		bp->flags |= BNXT_FLAG_SHARED_RINGS;
-	dflt_rings = netif_get_num_default_rss_queues();
+	dflt_rings = is_kdump_kernel() ? 1 : netif_get_num_default_rss_queues();
 	/* Reduce default rings on multi-port cards so that total default
 	 * rings do not exceed CPU count.
 	 */

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -20,6 +20,7 @@
 
 #include <linux/interrupt.h>
 #include <linux/rhashtable.h>
+#include <linux/crash_dump.h>
 #include <net/devlink.h>
 #include <net/dst_metadata.h>
 #include <net/xdp.h>
@@ -1369,7 +1370,8 @@ struct bnxt {
 #define BNXT_CHIP_TYPE_NITRO_A0(bp) ((bp)->flags & BNXT_FLAG_CHIP_NITRO_A0)
 #define BNXT_RX_PAGE_MODE(bp)	((bp)->flags & BNXT_FLAG_RX_PAGE_MODE)
 #define BNXT_SUPPORTS_TPA(bp)	(!BNXT_CHIP_TYPE_NITRO_A0(bp) &&	\
-				 !(bp->flags & BNXT_FLAG_CHIP_P5))
+				 !(bp->flags & BNXT_FLAG_CHIP_P5) &&	\
+				 !is_kdump_kernel())
 
 /* Chip class phase 5 */
 #define BNXT_CHIP_P5(bp)			\