net: macb: Add 64 bit addressing support for GEM

This patch adds support for 64 bit addressing and BDs.
-> Enable 64 bit addressing in DMACFG register.
-> Set DMA mask when design config register shows support for 64 bit addr.
-> Add new BD words for higher address when 64 bit DMA support is present.
-> Add and update TBQPH and RBQPH for MSB of BD pointers.
-> Change extraction and updation of buffer addresses to use
64 bit address.
-> In gem_rx extract address in one place insted of two and use a
separate flag for RXUSED.

Signed-off-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb.h

@@ -66,6 +66,8 @@
 #define MACB_USRIO		0x00c0
 #define MACB_WOL		0x00c4
 #define MACB_MID		0x00fc
+#define MACB_TBQPH		0x04C8
+#define MACB_RBQPH		0x04D4
 
 /* GEM register offsets. */
 #define GEM_NCFGR		0x0004 /* Network Config */
@@ -139,6 +141,7 @@
 
 #define GEM_ISR(hw_q)		(0x0400 + ((hw_q) << 2))
 #define GEM_TBQP(hw_q)		(0x0440 + ((hw_q) << 2))
+#define GEM_TBQPH(hw_q)		(0x04C8)
 #define GEM_RBQP(hw_q)		(0x0480 + ((hw_q) << 2))
 #define GEM_IER(hw_q)		(0x0600 + ((hw_q) << 2))
 #define GEM_IDR(hw_q)		(0x0620 + ((hw_q) << 2))
@@ -249,6 +252,8 @@
 #define GEM_RXBS_SIZE		8
 #define GEM_DDRP_OFFSET		24 /* disc_when_no_ahb */
 #define GEM_DDRP_SIZE		1
+#define GEM_ADDR64_OFFSET	30 /* Address bus width - 64b or 32b */
+#define GEM_ADDR64_SIZE		1
 
 
 /* Bitfields in NSR */
@@ -474,6 +479,10 @@
 struct macb_dma_desc {
 	u32	addr;
 	u32	ctrl;
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+	u32     addrh;
+	u32     resvd;
+#endif
 };
 
 /* DMA descriptor bitfields */
@@ -777,6 +786,7 @@ struct macb_queue {
 	unsigned int		IDR;
 	unsigned int		IMR;
 	unsigned int		TBQP;
+	unsigned int		TBQPH;
 
 	unsigned int		tx_head, tx_tail;
 	struct macb_dma_desc	*tx_ring;