net: ipa: introduce ipa_table_hash_support()

Introduce a new function to abstract the knowledge of whether hashed
routing and filter tables are supported for a given IPA instance.

IPA v4.2 is the only one that doesn't support hashed tables (now
and for the foreseeable future), but the name of the helper function
is better for explaining what's going on.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ipa/ipa_cmd.c

@@ -268,7 +268,7 @@ static bool ipa_cmd_register_write_valid(struct ipa *ipa)
 	/* If hashed tables are supported, ensure the hash flush register
 	 * offset will fit in a register write IPA immediate command.
 	 */
-	if (ipa->version != IPA_VERSION_4_2) {
+	if (ipa_table_hash_support(ipa)) {
 		offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
 		name = "filter/route hash flush";
 		if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))

drivers/net/ipa/ipa_table.c

 // SPDX-License-Identifier: GPL-2.0
 
 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
- * Copyright (C) 2018-2020 Linaro Ltd.
+ * Copyright (C) 2018-2021 Linaro Ltd.
  */
 
 #include <linux/types.h>
@@ -239,6 +239,11 @@ static void ipa_table_validate_build(void)
 
 #endif /* !IPA_VALIDATE */
 
+bool ipa_table_hash_support(struct ipa *ipa)
+{
+	return ipa->version != IPA_VERSION_4_2;
+}
+
 /* Zero entry count means no table, so just return a 0 address */
 static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count)
 {
@@ -412,8 +417,7 @@ int ipa_table_hash_flush(struct ipa *ipa)
 	struct gsi_trans *trans;
 	u32 val;
 
-	/* IPA version 4.2 does not support hashed tables */
-	if (ipa->version == IPA_VERSION_4_2)
+	if (!ipa_table_hash_support(ipa))
 		return 0;
 
 	trans = ipa_cmd_trans_alloc(ipa, 1);
@@ -531,8 +535,7 @@ static void ipa_filter_config(struct ipa *ipa, bool modem)
 	enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
 	u32 ep_mask = ipa->filter_map;
 
-	/* IPA version 4.2 has no hashed route tables */
-	if (ipa->version == IPA_VERSION_4_2)
+	if (!ipa_table_hash_support(ipa))
 		return;
 
 	while (ep_mask) {
@@ -582,8 +585,7 @@ static void ipa_route_config(struct ipa *ipa, bool modem)
 {
 	u32 route_id;
 
-	/* IPA version 4.2 has no hashed route tables */
-	if (ipa->version == IPA_VERSION_4_2)
+	if (!ipa_table_hash_support(ipa))
 		return;
 
 	for (route_id = 0; route_id < IPA_ROUTE_COUNT_MAX; route_id++)

drivers/net/ipa/ipa_table.h

 /* SPDX-License-Identifier: GPL-2.0 */
 
 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
- * Copyright (C) 2019-2020 Linaro Ltd.
+ * Copyright (C) 2019-2021 Linaro Ltd.
  */
 #ifndef _IPA_TABLE_H_
 #define _IPA_TABLE_H_
@@ -51,6 +51,12 @@ static inline bool ipa_filter_map_valid(struct ipa *ipa, u32 filter_mask)
 
 #endif /* !IPA_VALIDATE */
 
+/**
+ * ipa_table_hash_support() - Return true if hashed tables are supported
+ * @ipa:	IPA pointer
+ */
+bool ipa_table_hash_support(struct ipa *ipa);
+
 /**
  * ipa_table_reset() - Reset filter and route tables entries to "none"
  * @ipa:	IPA pointer