From 44f61b5c832c4085fcf476484efeaeef96dcfb8b Mon Sep 17 00:00:00 2001
From: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Date: Wed, 29 May 2019 16:39:51 +0300
Subject: [PATCH] iwlwifi: clear persistence bit according to device family
Git-commit: 44f61b5c832c4085fcf476484efeaeef96dcfb8b
Patch-mainline: v5.2-rc6
References: bsc#1111666

The driver attempts to clear persistence bit on any device familiy even
though only 9000 and 22000 families require it. Clear the bit only on
the relevant device families.

Each HW has different address to the write protection register. Use the
right register for each HW

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Fixes: 8954e1eb2270 ("iwlwifi: trans: Clear persistence bit when starting the FW")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wireless/intel/iwlwifi/iwl-prph.h   |    7 +++
 drivers/net/wireless/intel/iwlwifi/pcie/trans.c |   44 ++++++++++++++++++------
 2 files changed, 39 insertions(+), 12 deletions(-)

--- a/drivers/net/wireless/intel/iwlwifi/iwl-prph.h
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-prph.h
@@ -401,7 +401,12 @@ enum aux_misc_master1_en {
 #define AUX_MISC_MASTER1_SMPHR_STATUS	0xA20800
 #define RSA_ENABLE			0xA24B08
 #define PREG_AUX_BUS_WPROT_0		0xA04CC0
-#define PREG_PRPH_WPROT_0		0xA04CE0
+
+/* device family 9000 WPROT register */
+#define PREG_PRPH_WPROT_9000		0xA04CE0
+/* device family 22000 WPROT register */
+#define PREG_PRPH_WPROT_22000		0xA04D00
+
 #define SB_CPU_1_STATUS			0xA01E30
 #define SB_CPU_2_STATUS			0xA01E34
 #define UMAG_SB_CPU_1_STATUS		0xA038C0
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -1730,10 +1730,39 @@ static int iwl_pcie_init_msix_handler(st
 	return 0;
 }
 
+static int iwl_trans_pcie_clear_persistence_bit(struct iwl_trans *trans)
+{
+	u32 hpm, wprot;
+
+	switch (trans->cfg->device_family) {
+	case IWL_DEVICE_FAMILY_9000:
+		wprot = PREG_PRPH_WPROT_9000;
+		break;
+	case IWL_DEVICE_FAMILY_22000:
+		wprot = PREG_PRPH_WPROT_22000;
+		break;
+	default:
+		return 0;
+	}
+
+	hpm = iwl_trans_read_prph(trans, HPM_DEBUG);
+	if (hpm != 0xa5a5a5a0 && (hpm & PERSISTENCE_BIT)) {
+		u32 wprot_val = iwl_trans_read_prph(trans, wprot);
+
+		if (wprot_val & PREG_WFPM_ACCESS) {
+			IWL_ERR(trans,
+				"Error, can not clear persistence bit\n");
+			return -EPERM;
+		}
+		iwl_trans_write_prph(trans, HPM_DEBUG, hpm & ~PERSISTENCE_BIT);
+	}
+
+	return 0;
+}
+
 static int _iwl_trans_pcie_start_hw(struct iwl_trans *trans, bool low_power)
 {
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
-	u32 hpm;
 	int err;
 
 	lockdep_assert_held(&trans_pcie->mutex);
@@ -1744,16 +1773,9 @@ static int _iwl_trans_pcie_start_hw(stru
 		return err;
 	}
 
-	hpm = iwl_trans_read_prph(trans, HPM_DEBUG);
-	if (hpm != 0xa5a5a5a0 && (hpm & PERSISTENCE_BIT)) {
-		if (iwl_trans_read_prph(trans, PREG_PRPH_WPROT_0) &
-		    PREG_WFPM_ACCESS) {
-			IWL_ERR(trans,
-				"Error, can not clear persistence bit\n");
-			return -EPERM;
-		}
-		iwl_trans_write_prph(trans, HPM_DEBUG, hpm & ~PERSISTENCE_BIT);
-	}
+	err = iwl_trans_pcie_clear_persistence_bit(trans);
+	if (err)
+		return err;
 
 	iwl_trans_pcie_sw_reset(trans);