rt2x00: Implement HW encryption (rt73usb)

rt73usb supports hardware encryption.
rt73usb supports up to 4 shared keys and up to 64 pairwise keys.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/Kconfig

@@ -156,6 +156,7 @@ config RT73USB
 	depends on USB
 	select RT2X00_LIB_USB
 	select RT2X00_LIB_FIRMWARE
+	select RT2X00_LIB_CRYPTO
 	select CRC_ITU_T
 	---help---
 	  This adds support for rt2501 wireless chipset family.

drivers/net/wireless/rt2x00/rt73usb.h

@@ -92,6 +92,16 @@
 #define PAIRWISE_KEY_TABLE_BASE		0x1200
 #define PAIRWISE_TA_TABLE_BASE		0x1a00
 
+#define SHARED_KEY_ENTRY(__idx) \
+	( SHARED_KEY_TABLE_BASE + \
+		((__idx) * sizeof(struct hw_key_entry)) )
+#define PAIRWISE_KEY_ENTRY(__idx) \
+	( PAIRWISE_KEY_TABLE_BASE + \
+		((__idx) * sizeof(struct hw_key_entry)) )
+#define PAIRWISE_TA_ENTRY(__idx) \
+	( PAIRWISE_TA_TABLE_BASE + \
+		((__idx) * sizeof(struct hw_pairwise_ta_entry)) )
+
 struct hw_key_entry {
 	u8 key[16];
 	u8 tx_mic[8];
@@ -100,7 +110,8 @@ struct hw_key_entry {
 
 struct hw_pairwise_ta_entry {
 	u8 address[6];
-	u8 reserved[2];
+	u8 cipher;
+	u8 reserved;
 } __attribute__ ((packed));
 
 /*
@@ -563,6 +574,10 @@ struct hw_pairwise_ta_entry {
  * SEC_CSR4: Pairwise key table lookup control.
  */
 #define SEC_CSR4			0x30b0
+#define SEC_CSR4_ENABLE_BSS0		FIELD32(0x00000001)
+#define SEC_CSR4_ENABLE_BSS1		FIELD32(0x00000002)
+#define SEC_CSR4_ENABLE_BSS2		FIELD32(0x00000004)
+#define SEC_CSR4_ENABLE_BSS3		FIELD32(0x00000008)
 
 /*
  * SEC_CSR5: shared key table security mode register.
@@ -1010,8 +1025,10 @@ struct hw_pairwise_ta_entry {
 
 /*
  * Word4
+ * ICV: Received ICV of originally encrypted.
+ * NOTE: This is a guess, the official definition is "reserved"
  */
-#define RXD_W4_RESERVED			FIELD32(0xffffffff)
+#define RXD_W4_ICV			FIELD32(0xffffffff)
 
 /*
  * the above 20-byte is called RXINFO and will be DMAed to MAC RX block