iwlwifi: set auto clock gate disable bit for 6x00/6x50 series

For 6x00 and 6x50 series NIC with OTP shadow RAM, set auto clock gate
disable bit when initializing OTP access.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-csr.h

@@ -109,8 +109,9 @@
  * Bit fields:
  *  3-2:  0 = A, 1 = B, 2 = C, 3 = D step
  */
-#define CSR_HW_REV_WA_REG	(CSR_BASE+0x22C)
-#define CSR_DBG_HPET_MEM_REG	(CSR_BASE+0x240)
+#define CSR_HW_REV_WA_REG		(CSR_BASE+0x22C)
+#define CSR_DBG_HPET_MEM_REG		(CSR_BASE+0x240)
+#define CSR_DBG_LINK_PWR_MGMT_REG	(CSR_BASE+0x250)
 
 /* Bits for CSR_HW_IF_CONFIG_REG */
 #define CSR49_HW_IF_CONFIG_REG_BIT_4965_R	(0x00000010)
@@ -195,6 +196,7 @@
 #define CSR_RESET_REG_FLAG_SW_RESET                  (0x00000080)
 #define CSR_RESET_REG_FLAG_MASTER_DISABLED           (0x00000100)
 #define CSR_RESET_REG_FLAG_STOP_MASTER               (0x00000200)
+#define CSR_RESET_LINK_PWR_MGMT_DISABLED             (0x80000000)
 
 /* GP (general purpose) CONTROL */
 #define CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY        (0x00000001)

drivers/net/wireless/iwlwifi/iwl-eeprom.c

@@ -358,6 +358,14 @@ static int iwl_init_otp_access(struct iwl_priv *priv)
 		udelay(5);
 		iwl_clear_bits_prph(priv, APMG_PS_CTRL_REG,
 				    APMG_PS_CTRL_VAL_RESET_REQ);
+
+		/*
+		 * CSR auto clock gate disable bit -
+		 * this is only applicable for HW with OTP shadow RAM
+		 */
+		if (priv->cfg->shadow_ram_support)
+			iwl_set_bit(priv, CSR_DBG_LINK_PWR_MGMT_REG,
+				CSR_RESET_LINK_PWR_MGMT_DISABLED);
 	}
 	return ret;
 }