net: ethernet: ti: cpsw_ale: Fix warning on some platforms

The number of register fields cannot be assumed to be ALE_FIELDS_MAX
as some platforms can have lesser fields.

Solve this by embedding the actual number of fields available
in platform data and use that instead of ALE_FIELDS_MAX.

Gets rid of the below warning on BeagleBone Black

[    1.007735] WARNING: CPU: 0 PID: 33 at drivers/base/regmap/regmap.c:1208 regmap_field_init+0x88/0x9c
[    1.007802] invalid empty mask defined
[    1.007812] Modules linked in:
[    1.007842] CPU: 0 UID: 0 PID: 33 Comm: kworker/u4:3 Not tainted 6.11.0-01459-g508403ab7b74-dirty torvalds#840
[    1.007867] Hardware name: Generic AM33XX (Flattened Device Tree)
[    1.007890] Workqueue: events_unbound deferred_probe_work_func
[    1.007935] Call trace:
[    1.007957]  unwind_backtrace from show_stack+0x10/0x14
[    1.007999]  show_stack from dump_stack_lvl+0x50/0x64
[    1.008033]  dump_stack_lvl from __warn+0x70/0x124
[    1.008077]  __warn from warn_slowpath_fmt+0x194/0x1a8
[    1.008113]  warn_slowpath_fmt from regmap_field_init+0x88/0x9c
[    1.008154]  regmap_field_init from devm_regmap_field_alloc+0x48/0x64
[    1.008193]  devm_regmap_field_alloc from cpsw_ale_create+0xfc/0x320
[    1.008251]  cpsw_ale_create from cpsw_init_common+0x214/0x354
[    1.008286]  cpsw_init_common from cpsw_probe+0x4ac/0xb88

Reported-by: Geert Uytterhoeven <[email protected]>
Closes: https://lore.kernel.org/netdev/CAMuHMdUf-tKRDzkz2_m8qdFTFutefddU0NTratVrEjRTzA3yQQ@mail.gmail.com/
Fixes: 11cbcfe ("net: ethernet: ti: cpsw_ale: use regfields for number of Entries and Policers")
Signed-off-by: Roger Quadros <[email protected]>

Author: rogerq

drivers/net/ethernet/ti/cpsw_ale.c

@@ -96,6 +96,7 @@ enum {
  * @features: features supported by ALE
  * @tbl_entries: number of ALE entries
  * @reg_fields: pointer to array of register field configuration
+ * @num_fields: number of fields in the reg_fields array
  * @nu_switch_ale: NU Switch ALE
  * @vlan_entry_tbl: ALE vlan entry fields description tbl
  */
@@ -104,6 +105,7 @@ struct cpsw_ale_dev_id {
 	u32 features;
 	u32 tbl_entries;
 	const struct reg_field *reg_fields;
+	int num_fields;
 	bool nu_switch_ale;
 	const struct ale_entry_fld *vlan_entry_tbl;
 };
@@ -1400,19 +1402,22 @@ static const struct cpsw_ale_dev_id cpsw_ale_id_match[] = {
 		.dev_id = "cpsw",
 		.tbl_entries = 1024,
 		.reg_fields = ale_fields_cpsw,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw),
 		.vlan_entry_tbl = vlan_entry_cpsw,
 	},
 	{
 		/* 66ak2h_xgbe */
 		.dev_id = "66ak2h-xgbe",
 		.tbl_entries = 2048,
 		.reg_fields = ale_fields_cpsw,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw),
 		.vlan_entry_tbl = vlan_entry_cpsw,
 	},
 	{
 		.dev_id = "66ak2el",
 		.features = CPSW_ALE_F_STATUS_REG,
 		.reg_fields = ale_fields_cpsw_nu,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw_nu),
 		.nu_switch_ale = true,
 		.vlan_entry_tbl = vlan_entry_nu,
 	},
@@ -1421,6 +1426,7 @@ static const struct cpsw_ale_dev_id cpsw_ale_id_match[] = {
 		.features = CPSW_ALE_F_STATUS_REG,
 		.tbl_entries = 64,
 		.reg_fields = ale_fields_cpsw_nu,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw_nu),
 		.nu_switch_ale = true,
 		.vlan_entry_tbl = vlan_entry_nu,
 	},
@@ -1429,19 +1435,22 @@ static const struct cpsw_ale_dev_id cpsw_ale_id_match[] = {
 		.features = CPSW_ALE_F_STATUS_REG | CPSW_ALE_F_HW_AUTOAGING,
 		.tbl_entries = 64,
 		.reg_fields = ale_fields_cpsw_nu,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw_nu),
 		.nu_switch_ale = true,
 		.vlan_entry_tbl = vlan_entry_nu,
 	},
 	{
 		.dev_id = "j721e-cpswxg",
 		.features = CPSW_ALE_F_STATUS_REG | CPSW_ALE_F_HW_AUTOAGING,
 		.reg_fields = ale_fields_cpsw_nu,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw_nu),
 		.vlan_entry_tbl = vlan_entry_k3_cpswxg,
 	},
 	{
 		.dev_id = "am64-cpswxg",
 		.features = CPSW_ALE_F_STATUS_REG | CPSW_ALE_F_HW_AUTOAGING,
 		.reg_fields = ale_fields_cpsw_nu,
+		.num_fields = ARRAY_SIZE(ale_fields_cpsw_nu),
 		.vlan_entry_tbl = vlan_entry_k3_cpswxg,
 		.tbl_entries = 512,
 	},
@@ -1477,7 +1486,7 @@ static int cpsw_ale_regfield_init(struct cpsw_ale *ale)
 	struct regmap *regmap = ale->regmap;
 	int i;
 
-	for (i = 0; i < ALE_FIELDS_MAX; i++) {
+	for (i = 0; i < ale->params.num_fields; i++) {
 		ale->fields[i] = devm_regmap_field_alloc(dev, regmap,
 							 reg_fields[i]);
 		if (IS_ERR(ale->fields[i])) {
@@ -1503,6 +1512,7 @@ struct cpsw_ale *cpsw_ale_create(struct cpsw_ale_params *params)
 	params->ale_entries = ale_dev_id->tbl_entries;
 	params->nu_switch_ale = ale_dev_id->nu_switch_ale;
 	params->reg_fields = ale_dev_id->reg_fields;
+	params->num_fields = ale_dev_id->num_fields;
 
 	ale = devm_kzalloc(params->dev, sizeof(*ale), GFP_KERNEL);
 	if (!ale)

drivers/net/ethernet/ti/cpsw_ale.h

@@ -24,6 +24,7 @@ struct cpsw_ale_params {
 	 */
 	bool			nu_switch_ale;
 	const struct reg_field *reg_fields;
+	int			num_fields;
 	const char		*dev_id;
 	unsigned long		bus_freq;
 };