wifi: iwlwifi: uefi: cache the DSM functions

Just like we did for ACPI, cache the UEFI values to avoid reading the
tables over and over again.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20260111193638.15871db3cfab.Ib39db197646cc303d60bb12448794d20f6ccbd15@changeid

2 files changed, 51 insertions, 16 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/runtime.h b/drivers/net/wireless/intel/iwlwifi/fw/runtime.h
index b9e5f8ea8f94..a655bca75301 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/runtime.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/runtime.h
@@ -216,7 +216,7 @@ struct iwl_fw_runtime {
 	u8 uefi_tables_lock_status;
 	struct iwl_phy_specific_cfg phy_filters;
 
-#ifdef CONFIG_ACPI
+#if defined(CONFIG_ACPI) || defined(CONFIG_EFI)
 	u32 dsm_funcs_valid;
 	u32 dsm_values[DSM_FUNC_NUM_FUNCS];
 #endif
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
index 4ae4d215e633..acccb22a833c 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
@@ -721,17 +721,12 @@ out:
 	return ret;
 }
 
-int iwl_uefi_get_dsm(struct iwl_fw_runtime *fwrt, enum iwl_dsm_funcs func,
-		     u32 *value)
+static int iwl_uefi_load_dsm_values(struct iwl_fw_runtime *fwrt)
 {
 	struct uefi_cnv_var_general_cfg *data;
 	int ret = -EINVAL;
 
-	BUILD_BUG_ON(ARRAY_SIZE(data->functions) < DSM_FUNC_NUM_FUNCS);
-
-	/* Not supported function index */
-	if (func >= DSM_FUNC_NUM_FUNCS || func == 5)
-		return -EOPNOTSUPP;
+	BUILD_BUG_ON(ARRAY_SIZE(data->functions) < ARRAY_SIZE(fwrt->dsm_values));
 
 	data = iwl_uefi_get_verified_variable(fwrt->trans, IWL_UEFI_DSM_NAME,
 					      "DSM", sizeof(*data), NULL);
@@ -744,23 +739,63 @@ int iwl_uefi_get_dsm(struct iwl_fw_runtime *fwrt, enum iwl_dsm_funcs func,
 		goto out;
 	}
 
-	if (!(data->functions[DSM_FUNC_QUERY] & BIT(func))) {
-		IWL_DEBUG_RADIO(fwrt, "DSM func %d not in 0x%x\n",
-				func, data->functions[DSM_FUNC_QUERY]);
-		goto out;
-	}
+	fwrt->dsm_funcs_valid = data->functions[DSM_FUNC_QUERY];
 
-	*value = data->functions[func];
+	/*
+	 * Make sure we don't load the DSM values twice. Set this only after we
+	 * validated the DSM table so that if the table in UEFI is not valid,
+	 * we will fallback to ACPI.
+	 */
+	fwrt->dsm_funcs_valid |= BIT(DSM_FUNC_QUERY);
 
-	IWL_DEBUG_RADIO(fwrt,
-			"UEFI: DSM func=%d: value=%d\n", func, *value);
+	for (int func = 1; func < ARRAY_SIZE(fwrt->dsm_values); func++) {
+		if (!(fwrt->dsm_funcs_valid & BIT(func))) {
+			IWL_DEBUG_RADIO(fwrt, "DSM func %d not in 0x%x\n",
+					func, fwrt->dsm_funcs_valid);
+			continue;
+		}
 
+		fwrt->dsm_values[func] = data->functions[func];
+
+		IWL_DEBUG_RADIO(fwrt,
+				"UEFI: DSM func=%d: value=%d\n", func,
+				fwrt->dsm_values[func]);
+	}
 	ret = 0;
+
 out:
 	kfree(data);
 	return ret;
 }
 
+int iwl_uefi_get_dsm(struct iwl_fw_runtime *fwrt, enum iwl_dsm_funcs func,
+		     u32 *value)
+{
+	/* Not supported function index */
+	if (func >= DSM_FUNC_NUM_FUNCS || func == 5)
+		return -EOPNOTSUPP;
+
+	if (!fwrt->dsm_funcs_valid) {
+		int ret = iwl_uefi_load_dsm_values(fwrt);
+
+		if (ret)
+			return ret;
+	}
+
+	if (!(fwrt->dsm_funcs_valid & BIT(func))) {
+		IWL_DEBUG_RADIO(fwrt, "DSM func %d not in 0x%x\n",
+				func, fwrt->dsm_funcs_valid);
+		return -EINVAL;
+	}
+
+	*value = fwrt->dsm_values[func];
+
+	IWL_DEBUG_RADIO(fwrt,
+			"UEFI: DSM func=%d: value=%d\n", func, *value);
+
+	return 0;
+}
+
 int iwl_uefi_get_puncturing(struct iwl_fw_runtime *fwrt)
 {
 	struct uefi_cnv_var_puncturing_data *data;