wifi: iwlwifi: read WRDD table from UEFI

Try to read the WRDD table from UEFI first,
and if the WIFI UEFI tables are unlocked or the
table doesn't exist - try to read it from ACPI.

Change iwl_acpi_get_mcc() to receive fwrt as argument so
it will be the same as all iwl_acpi_get_x() functions,
so it could be generated by the macro.

Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://msgid.link/20240201155157.5d52eeb109f7.I4d81700a7ae7fe2dfee14e363de358be59de7823@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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

@@ -326,17 +326,18 @@ int iwl_acpi_get_tas_table(struct iwl_fw_runtime *fwrt,
 	return ret;
 }
 
-int iwl_acpi_get_mcc(struct device *dev, char *mcc)
+int iwl_acpi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc)
 {
 	union acpi_object *wifi_pkg, *data;
 	u32 mcc_val;
 	int ret, tbl_rev;
 
-	data = iwl_acpi_get_object(dev, ACPI_WRDD_METHOD);
+	data = iwl_acpi_get_object(fwrt->dev, ACPI_WRDD_METHOD);
 	if (IS_ERR(data))
 		return PTR_ERR(data);
 
-	wifi_pkg = iwl_acpi_get_wifi_pkg(dev, data, ACPI_WRDD_WIFI_DATA_SIZE,
+	wifi_pkg = iwl_acpi_get_wifi_pkg(fwrt->dev, data,
+					 ACPI_WRDD_WIFI_DATA_SIZE,
 					 &tbl_rev);
 	if (IS_ERR(wifi_pkg)) {
 		ret = PTR_ERR(wifi_pkg);
@@ -360,7 +361,6 @@ int iwl_acpi_get_mcc(struct device *dev, char *mcc)
 	kfree(data);
 	return ret;
 }
-IWL_EXPORT_SYMBOL(iwl_acpi_get_mcc);
 
 int iwl_acpi_get_pwr_limit(struct iwl_fw_runtime *fwrt, u64 *dflt_pwr_limit)
 {

drivers/net/wireless/intel/iwlwifi/fw/acpi.h

@@ -149,12 +149,12 @@ int iwl_acpi_get_dsm_u32(struct device *dev, int rev, int func,
 /**
  * iwl_acpi_get_mcc - read MCC from ACPI, if available
  *
- * @dev: the struct device
+ * @fwrt: the fw runtime struct
  * @mcc: output buffer (3 bytes) that will get the MCC
  *
  * This function tries to read the current MCC from ACPI if available.
  */
-int iwl_acpi_get_mcc(struct device *dev, char *mcc);
+int iwl_acpi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc);
 
 int iwl_acpi_get_pwr_limit(struct iwl_fw_runtime *fwrt, u64 *dflt_pwr_limit);
 
@@ -207,7 +207,7 @@ static inline int iwl_acpi_get_dsm_u32(struct device *dev, int rev, int func,
 	return -ENOENT;
 }
 
-static inline int iwl_acpi_get_mcc(struct device *dev, char *mcc)
+static inline int iwl_acpi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc)
 {
 	return -ENOENT;
 }

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

@@ -36,6 +36,7 @@ IWL_BIOS_TABLE_LOADER(wgds_table);
 IWL_BIOS_TABLE_LOADER(ppag_table);
 IWL_BIOS_TABLE_LOADER_DATA(tas_table, struct iwl_tas_data);
 IWL_BIOS_TABLE_LOADER_DATA(pwr_limit, u64);
+IWL_BIOS_TABLE_LOADER_DATA(mcc, char);
 
 
 static const struct dmi_system_id dmi_ppag_approved_list[] = {

drivers/net/wireless/intel/iwlwifi/fw/regulatory.h

@@ -139,4 +139,6 @@ int iwl_bios_get_tas_table(struct iwl_fw_runtime *fwrt,
 
 int iwl_bios_get_pwr_limit(struct iwl_fw_runtime *fwrt,
 			   u64 *dflt_pwr_limit);
+
+int iwl_bios_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc);
 #endif /* __fw_regulatory_h__ */

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

@@ -621,3 +621,34 @@ int iwl_uefi_get_pwr_limit(struct iwl_fw_runtime *fwrt,
 	kfree(data);
 	return ret;
 }
+
+int iwl_uefi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc)
+{
+	struct uefi_cnv_var_wrdd *data;
+	int ret = 0;
+
+	data = iwl_uefi_get_verified_variable(fwrt->trans, IWL_UEFI_WRDD_NAME,
+					      "WRDD", sizeof(*data), NULL);
+	if (IS_ERR(data))
+		return -EINVAL;
+
+	if (data->revision != IWL_UEFI_WRDD_REVISION) {
+		ret = -EINVAL;
+		IWL_DEBUG_RADIO(fwrt, "Unsupported UEFI WRDD revision:%d\n",
+				data->revision);
+		goto out;
+	}
+
+	if (data->mcc != UEFI_MCC_CHINA) {
+		ret = -EINVAL;
+		IWL_DEBUG_RADIO(fwrt, "UEFI WRDD is supported only for CN\n");
+		goto out;
+	}
+
+	mcc[0] = (data->mcc >> 8) & 0xff;
+	mcc[1] = data->mcc & 0xff;
+	mcc[2] = '\0';
+out:
+	kfree(data);
+	return ret;
+}

drivers/net/wireless/intel/iwlwifi/fw/uefi.h

@@ -18,6 +18,7 @@
 #define IWL_UEFI_PPAG_NAME		L"UefiCnvWlanPPAG"
 #define IWL_UEFI_WTAS_NAME		L"UefiCnvWlanWTAS"
 #define IWL_UEFI_SPLC_NAME		L"UefiCnvWlanSPLC"
+#define IWL_UEFI_WRDD_NAME		L"UefiCnvWlanWRDD"
 
 
 #define IWL_SGOM_MAP_SIZE		339
@@ -30,6 +31,7 @@
 #define IWL_UEFI_MAX_PPAG_REV		3
 #define IWL_UEFI_WTAS_REVISION		1
 #define IWL_UEFI_SPLC_REVISION		0
+#define IWL_UEFI_WRDD_REVISION		0
 
 struct pnvm_sku_package {
 	u8 rev;
@@ -142,6 +144,17 @@ struct uefi_cnv_var_splc {
 	u32 default_pwr_limit;
 } __packed;
 
+#define UEFI_MCC_CHINA 0x434e
+
+/* struct uefi_cnv_var_wrdd - WRDD table as defined in UEFI
+ * @revision: the revision of the table
+ * @mcc: country identifier as defined in ISO/IEC 3166-1 Alpha 2 code
+ */
+struct uefi_cnv_var_wrdd {
+	u8 revision;
+	u32 mcc;
+} __packed;
+
 /*
  * This is known to be broken on v4.19 and to work on v5.4.  Until we
  * figure out why this is the case and how to make it work, simply
@@ -164,6 +177,7 @@ int iwl_uefi_get_tas_table(struct iwl_fw_runtime *fwrt,
 			   struct iwl_tas_data *data);
 int iwl_uefi_get_pwr_limit(struct iwl_fw_runtime *fwrt,
 			   u64 *dflt_pwr_limit);
+int iwl_uefi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc);
 #else /* CONFIG_EFI */
 static inline void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
 {
@@ -227,6 +241,11 @@ static inline int iwl_uefi_get_pwr_limit(struct iwl_fw_runtime *fwrt,
 	*dflt_pwr_limit = 0;
 	return 0;
 }
+
+static inline int iwl_uefi_get_mcc(struct iwl_fw_runtime *fwrt, char *mcc)
+{
+	return -ENOENT;
+}
 #endif /* CONFIG_EFI */
 
 #if defined(CONFIG_EFI) && defined(CONFIG_ACPI)

drivers/net/wireless/intel/iwlwifi/mvm/nvm.c

@@ -590,7 +590,7 @@ int iwl_mvm_init_mcc(struct iwl_mvm *mvm)
 		return -EIO;
 
 	if (iwl_mvm_is_wifi_mcc_supported(mvm) &&
-	    !iwl_acpi_get_mcc(mvm->dev, mcc)) {
+	    !iwl_bios_get_mcc(&mvm->fwrt, mcc)) {
 		kfree(regd);
 		regd = iwl_mvm_get_regdomain(mvm->hw->wiphy, mcc,
 					     MCC_SOURCE_BIOS, NULL);