wifi: iwlwifi: pnvm: handle memory descriptor tlv

When PNVM is obtained from UEFI, there's an additional memory
descriptor TLV that has to be handled. It is the same TLV that
holds data in the reduced power tables. Also, in this TLV, the
actual data is located after address and size, so add the
corresponding offset.

Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230606103519.8c5f5ee8e30b.Id1893c9dec140b5ba4abe8a121c2e1a1d121d2d7@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 59 insertions, 17 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c b/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
index 82eb32e67a2c..650e4bde9c17 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/pnvm.c
@@ -127,6 +127,11 @@ static int iwl_pnvm_handle_section(struct iwl_trans *trans, const u8 *data,
 
 			break;
 		}
+		case IWL_UCODE_TLV_MEM_DESC:
+			if (iwl_uefi_handle_tlv_mem_desc(trans, data, tlv_len,
+							 pnvm_data))
+				return -EINVAL;
+			break;
 		case IWL_UCODE_TLV_PNVM_SKU:
 			IWL_DEBUG_FW(trans,
 				     "New PNVM section started, stop parsing.\n");
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
index 488b9fb79743..9877988db0d2 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
@@ -17,6 +17,12 @@
 				  0xb2, 0xec, 0xf5, 0xa3,	\
 				  0x59, 0x4f, 0x4a, 0xea)
 
+struct iwl_uefi_pnvm_mem_desc {
+	__le32 addr;
+	__le32 size;
+	const u8 data[];
+} __packed;
+
 static void *iwl_uefi_get_variable(efi_char16_t *name, efi_guid_t *guid,
 				   unsigned long *data_size)
 {
@@ -70,6 +76,42 @@ void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
 	return data;
 }
 
+int iwl_uefi_handle_tlv_mem_desc(struct iwl_trans *trans, const u8 *data,
+				 u32 tlv_len, struct iwl_pnvm_image *pnvm_data)
+{
+	const struct iwl_uefi_pnvm_mem_desc *desc = (const void *)data;
+	u32 data_len;
+
+	if (tlv_len < sizeof(*desc)) {
+		IWL_DEBUG_FW(trans, "TLV len (%d) is too small\n", tlv_len);
+		return -EINVAL;
+	}
+
+	data_len = tlv_len - sizeof(*desc);
+
+	IWL_DEBUG_FW(trans,
+		     "Handle IWL_UCODE_TLV_MEM_DESC, len %d data_len %d\n",
+		     tlv_len, data_len);
+
+	if (le32_to_cpu(desc->size) != data_len) {
+		IWL_DEBUG_FW(trans, "invalid mem desc size %d\n", desc->size);
+		return -EINVAL;
+	}
+
+	if (pnvm_data->n_chunks == IPC_DRAM_MAP_ENTRY_NUM_MAX) {
+		IWL_DEBUG_FW(trans, "too many payloads to allocate in DRAM.\n");
+		return -EINVAL;
+	}
+
+	IWL_DEBUG_FW(trans, "Adding data (size %d)\n", data_len);
+
+	pnvm_data->chunks[pnvm_data->n_chunks].data = desc->data;
+	pnvm_data->chunks[pnvm_data->n_chunks].len = data_len;
+	pnvm_data->n_chunks++;
+
+	return 0;
+}
+
 static int iwl_uefi_reduce_power_section(struct iwl_trans *trans,
 					 const u8 *data, size_t len,
 					 struct iwl_pnvm_image *pnvm_data)
@@ -97,25 +139,11 @@ static int iwl_uefi_reduce_power_section(struct iwl_trans *trans,
 		data += sizeof(*tlv);
 
 		switch (tlv_type) {
-		case IWL_UCODE_TLV_MEM_DESC: {
-			IWL_DEBUG_FW(trans,
-				     "Got IWL_UCODE_TLV_MEM_DESC len %d\n",
-				     tlv_len);
-
-			if (pnvm_data->n_chunks == IPC_DRAM_MAP_ENTRY_NUM_MAX) {
-				IWL_DEBUG_FW(trans,
-				"too many payloads to allocate in DRAM.\n");
+		case IWL_UCODE_TLV_MEM_DESC:
+			if (iwl_uefi_handle_tlv_mem_desc(trans, data, tlv_len,
+							 pnvm_data))
 				return -EINVAL;
-			}
-
-			IWL_DEBUG_FW(trans, "Adding data (size %d)\n", tlv_len);
-
-			pnvm_data->chunks[pnvm_data->n_chunks].data = data;
-			pnvm_data->chunks[pnvm_data->n_chunks].len = tlv_len;
-			pnvm_data->n_chunks++;
-
 			break;
-		}
 		case IWL_UCODE_TLV_PNVM_SKU:
 			IWL_DEBUG_FW(trans,
 				     "New REDUCE_POWER section started, stop parsing.\n");
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.h b/drivers/net/wireless/intel/iwlwifi/fw/uefi.h
index dc7ccf49d92d..1369cc4855c3 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.h
@@ -46,6 +46,8 @@ int iwl_uefi_reduce_power_parse(struct iwl_trans *trans,
 				const u8 *data, size_t len,
 				struct iwl_pnvm_image *pnvm_data);
 void iwl_uefi_get_step_table(struct iwl_trans *trans);
+int iwl_uefi_handle_tlv_mem_desc(struct iwl_trans *trans, const u8 *data,
+				 u32 tlv_len, struct iwl_pnvm_image *pnvm_data);
 #else /* CONFIG_EFI */
 static inline void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
 {
@@ -69,6 +71,13 @@ iwl_uefi_get_reduced_power(struct iwl_trans *trans, size_t *len)
 static inline void iwl_uefi_get_step_table(struct iwl_trans *trans)
 {
 }
+
+static inline int
+iwl_uefi_handle_tlv_mem_desc(struct iwl_trans *trans, const u8 *data,
+			     u32 tlv_len, struct iwl_pnvm_image *pnvm_data)
+{
+	return 0;
+}
 #endif /* CONFIG_EFI */
 
 #if defined(CONFIG_EFI) && defined(CONFIG_ACPI)