wifi: iwlwifi: unify checks for HW error values

The hardware, depending on which part fails or times out,
returns 0xA5A5A5A. or 0x5A5A5A5. with the lowest 4 bits
encoding some further reason/status. However, mostly we
don't really need to care about the exact reasons, so
unify the checks for this to avoid hardcoding those magic
values all over the driver.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230612184434.3e2959741a38.I1c297a53787b87e4e2b8f296c041921338573f4d@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/fw/dbg.c

@@ -1038,7 +1038,7 @@ iwl_dump_ini_prph_mac_iter(struct iwl_fw_runtime *fwrt,
 	range->range_data_size = reg->dev_addr.size;
 	for (i = 0; i < le32_to_cpu(reg->dev_addr.size); i += 4) {
 		prph_val = iwl_read_prph(fwrt->trans, addr + i);
-		if ((prph_val & ~0xf) == 0xa5a5a5a0)
+		if (iwl_trans_is_hw_error_value(prph_val))
 			return -EBUSY;
 		*val++ = cpu_to_le32(prph_val);
 	}
@@ -1562,7 +1562,7 @@ iwl_dump_ini_dbgi_sram_iter(struct iwl_fw_runtime *fwrt,
 		prph_data = iwl_read_prph_no_grab(fwrt->trans, (i % 2) ?
 					  DBGI_SRAM_TARGET_ACCESS_RDATA_MSB :
 					  DBGI_SRAM_TARGET_ACCESS_RDATA_LSB);
-		if ((prph_data & ~0xf) == 0xa5a5a5a0) {
+		if (iwl_trans_is_hw_error_value(prph_data)) {
 			iwl_trans_release_nic_access(fwrt->trans);
 			return -EBUSY;
 		}

drivers/net/wireless/intel/iwlwifi/fw/dump.c

@@ -194,7 +194,7 @@ static void iwl_fwrt_dump_lmac_error_log(struct iwl_fw_runtime *fwrt, u8 lmac_nu
 
 	/* check if there is a HW error */
 	val = iwl_trans_read_mem32(trans, base);
-	if (((val & ~0xf) == 0xa5a5a5a0) || ((val & ~0xf) == 0x5a5a5a50)) {
+	if (iwl_trans_is_hw_error_value(val)) {
 		int err;
 
 		IWL_ERR(trans, "HW error, resetting before reading\n");

drivers/net/wireless/intel/iwlwifi/iwl-io.c

 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
 /*
- * Copyright (C) 2003-2014, 2018-2021 Intel Corporation
+ * Copyright (C) 2003-2014, 2018-2022 Intel Corporation
  * Copyright (C) 2015-2016 Intel Deutschland GmbH
  */
 #include <linux/delay.h>
@@ -72,6 +72,7 @@ u32 iwl_read_direct32(struct iwl_trans *trans, u32 reg)
 		return value;
 	}
 
+	/* return as if we have a HW timeout/failure */
 	return 0x5a5a5a5a;
 }
 IWL_EXPORT_SYMBOL(iwl_read_direct32);
@@ -143,6 +144,7 @@ u32 iwl_read_prph(struct iwl_trans *trans, u32 ofs)
 		return val;
 	}
 
+	/* return as if we have a HW timeout/failure */
 	return 0x5a5a5a5a;
 }
 IWL_EXPORT_SYMBOL(iwl_read_prph);

drivers/net/wireless/intel/iwlwifi/iwl-trans.h

@@ -1613,6 +1613,11 @@ struct iwl_trans *iwl_trans_alloc(unsigned int priv_size,
 int iwl_trans_init(struct iwl_trans *trans);
 void iwl_trans_free(struct iwl_trans *trans);
 
+static inline bool iwl_trans_is_hw_error_value(u32 val)
+{
+	return ((val & ~0xf) == 0xa5a5a5a0) || ((val & ~0xf) == 0x5a5a5a50);
+}
+
 /*****************************************************
 * driver (transport) register/unregister functions
 ******************************************************/

drivers/net/wireless/intel/iwlwifi/pcie/rx.c

@@ -1873,7 +1873,7 @@ irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
 		return IRQ_NONE;
 	}
 
-	if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
+	if (unlikely(inta == 0xFFFFFFFF || iwl_trans_is_hw_error_value(inta))) {
 		/*
 		 * Hardware disappeared. It might have
 		 * already raised an interrupt.

drivers/net/wireless/intel/iwlwifi/pcie/trans.c

@@ -1788,7 +1788,7 @@ static int iwl_trans_pcie_clear_persistence_bit(struct iwl_trans *trans)
 	}
 
 	hpm = iwl_read_umac_prph_no_grab(trans, HPM_DEBUG);
-	if (hpm != 0xa5a5a5a0 && (hpm & PERSISTENCE_BIT)) {
+	if (!iwl_trans_is_hw_error_value(hpm) && (hpm & PERSISTENCE_BIT)) {
 		u32 wprot_val = iwl_read_umac_prph_no_grab(trans, wprot);
 
 		if (wprot_val & PREG_WFPM_ACCESS) {