sfc: parse headers of devlink flash images

This parsing is necessary to obtain the metadata which will be
 used in a subsequent patch to write the image to the device.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://patch.msgid.link/65318300f3f1b1462925f917f7c0d0ac833955ae.1739186253.git.ecree.xilinx@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Edward Cree

drivers/net/ethernet/sfc/Makefile

@@ -7,7 +7,7 @@ sfc-y			+= efx.o efx_common.o efx_channels.o nic.o \
 			   mcdi_functions.o mcdi_filters.o mcdi_mon.o \
 			   ef100.o ef100_nic.o ef100_netdev.o \
 			   ef100_ethtool.o ef100_rx.o ef100_tx.o \
-			   efx_devlink.o
+			   efx_devlink.o efx_reflash.o
 sfc-$(CONFIG_SFC_MTD)	+= mtd.o
 sfc-$(CONFIG_SFC_SRIOV)	+= sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o \
                            mae.o tc.o tc_bindings.o tc_counters.o \

drivers/net/ethernet/sfc/efx_devlink.c

@@ -19,6 +19,7 @@
 #include "mae.h"
 #include "ef100_rep.h"
 #endif
+#include "efx_reflash.h"
 
 struct efx_devlink {
 	struct efx_nic *efx;
@@ -615,7 +616,19 @@ static int efx_devlink_info_get(struct devlink *devlink,
 	return 0;
 }
 
+static int efx_devlink_flash_update(struct devlink *devlink,
+				    struct devlink_flash_update_params *params,
+				    struct netlink_ext_ack *extack)
+{
+	struct efx_devlink *devlink_private = devlink_priv(devlink);
+	struct efx_nic *efx = devlink_private->efx;
+
+	return efx_reflash_flash_firmware(efx, params->fw, extack);
+}
+
 static const struct devlink_ops sfc_devlink_ops = {
+	.supported_flash_update_params	= 0,
+	.flash_update			= efx_devlink_flash_update,
 	.info_get			= efx_devlink_info_get,
 };
 

drivers/net/ethernet/sfc/efx_reflash.c

@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/****************************************************************************
+ * Driver for AMD network controllers and boards
+ * Copyright (C) 2025, Advanced Micro Devices, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#include <linux/crc32.h>
+#include <net/devlink.h>
+#include "efx_reflash.h"
+#include "net_driver.h"
+#include "fw_formats.h"
+#include "mcdi_pcol.h"
+#include "mcdi.h"
+
+/* Try to parse a Reflash header at the specified offset */
+static bool efx_reflash_parse_reflash_header(const struct firmware *fw,
+					     size_t header_offset, u32 *type,
+					     u32 *subtype, const u8 **data,
+					     size_t *data_size)
+{
+	size_t header_end, trailer_offset, trailer_end;
+	u32 magic, version, payload_size, header_len;
+	const u8 *header, *trailer;
+	u32 expected_crc, crc;
+
+	if (check_add_overflow(header_offset, EFX_REFLASH_HEADER_LENGTH_OFST +
+					      EFX_REFLASH_HEADER_LENGTH_LEN,
+			       &header_end))
+		return false;
+	if (fw->size < header_end)
+		return false;
+
+	header = fw->data + header_offset;
+	magic = get_unaligned_le32(header + EFX_REFLASH_HEADER_MAGIC_OFST);
+	if (magic != EFX_REFLASH_HEADER_MAGIC_VALUE)
+		return false;
+
+	version = get_unaligned_le32(header + EFX_REFLASH_HEADER_VERSION_OFST);
+	if (version != EFX_REFLASH_HEADER_VERSION_VALUE)
+		return false;
+
+	payload_size = get_unaligned_le32(header + EFX_REFLASH_HEADER_PAYLOAD_SIZE_OFST);
+	header_len = get_unaligned_le32(header + EFX_REFLASH_HEADER_LENGTH_OFST);
+	if (check_add_overflow(header_offset, header_len, &trailer_offset) ||
+	    check_add_overflow(trailer_offset, payload_size, &trailer_offset) ||
+	    check_add_overflow(trailer_offset, EFX_REFLASH_TRAILER_LEN,
+			       &trailer_end))
+		return false;
+	if (fw->size < trailer_end)
+		return false;
+
+	trailer = fw->data + trailer_offset;
+	expected_crc = get_unaligned_le32(trailer + EFX_REFLASH_TRAILER_CRC_OFST);
+	/* Addition could overflow u32, but not size_t since we already
+	 * checked trailer_offset didn't overflow.  So cast to size_t first.
+	 */
+	crc = crc32_le(0, header, (size_t)header_len + payload_size);
+	if (crc != expected_crc)
+		return false;
+
+	*type = get_unaligned_le32(header + EFX_REFLASH_HEADER_FIRMWARE_TYPE_OFST);
+	*subtype = get_unaligned_le32(header + EFX_REFLASH_HEADER_FIRMWARE_SUBTYPE_OFST);
+	if (*type == EFX_REFLASH_FIRMWARE_TYPE_BUNDLE) {
+		/* All the bundle data is written verbatim to NVRAM */
+		*data = fw->data;
+		*data_size = fw->size;
+	} else {
+		/* Other payload types strip the reflash header and trailer
+		 * from the data written to NVRAM
+		 */
+		*data = header + header_len;
+		*data_size = payload_size;
+	}
+
+	return true;
+}
+
+/* Map from FIRMWARE_TYPE to NVRAM_PARTITION_TYPE */
+static int efx_reflash_partition_type(u32 type, u32 subtype,
+				      u32 *partition_type,
+				      u32 *partition_subtype)
+{
+	int rc = 0;
+
+	switch (type) {
+	case EFX_REFLASH_FIRMWARE_TYPE_BOOTROM:
+		*partition_type = NVRAM_PARTITION_TYPE_EXPANSION_ROM;
+		*partition_subtype = subtype;
+		break;
+	case EFX_REFLASH_FIRMWARE_TYPE_BUNDLE:
+		*partition_type = NVRAM_PARTITION_TYPE_BUNDLE;
+		*partition_subtype = subtype;
+		break;
+	default:
+		/* Not supported */
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+/* Try to parse a SmartNIC image header at the specified offset */
+static bool efx_reflash_parse_snic_header(const struct firmware *fw,
+					  size_t header_offset,
+					  u32 *partition_type,
+					  u32 *partition_subtype,
+					  const u8 **data, size_t *data_size)
+{
+	u32 magic, version, payload_size, header_len, expected_crc, crc;
+	size_t header_end, payload_end;
+	const u8 *header;
+
+	if (check_add_overflow(header_offset, EFX_SNICIMAGE_HEADER_MINLEN,
+			       &header_end) ||
+	    fw->size < header_end)
+		return false;
+
+	header = fw->data + header_offset;
+	magic = get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_MAGIC_OFST);
+	if (magic != EFX_SNICIMAGE_HEADER_MAGIC_VALUE)
+		return false;
+
+	version = get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_VERSION_OFST);
+	if (version != EFX_SNICIMAGE_HEADER_VERSION_VALUE)
+		return false;
+
+	header_len = get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_LENGTH_OFST);
+	if (check_add_overflow(header_offset, header_len, &header_end))
+		return false;
+	payload_size = get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_PAYLOAD_SIZE_OFST);
+	if (check_add_overflow(header_end, payload_size, &payload_end) ||
+	    fw->size < payload_end)
+		return false;
+
+	expected_crc = get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_CRC_OFST);
+
+	/* Calculate CRC omitting the expected CRC field itself */
+	crc = crc32_le(~0, header, EFX_SNICIMAGE_HEADER_CRC_OFST);
+	crc = ~crc32_le(crc,
+			header + EFX_SNICIMAGE_HEADER_CRC_OFST +
+			EFX_SNICIMAGE_HEADER_CRC_LEN,
+			header_len + payload_size - EFX_SNICIMAGE_HEADER_CRC_OFST -
+			EFX_SNICIMAGE_HEADER_CRC_LEN);
+	if (crc != expected_crc)
+		return false;
+
+	*partition_type =
+		get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_PARTITION_TYPE_OFST);
+	*partition_subtype =
+		get_unaligned_le32(header + EFX_SNICIMAGE_HEADER_PARTITION_SUBTYPE_OFST);
+	*data = fw->data;
+	*data_size = fw->size;
+	return true;
+}
+
+/* Try to parse a SmartNIC bundle header at the specified offset */
+static bool efx_reflash_parse_snic_bundle_header(const struct firmware *fw,
+						 size_t header_offset,
+						 u32 *partition_type,
+						 u32 *partition_subtype,
+						 const u8 **data,
+						 size_t *data_size)
+{
+	u32 magic, version, bundle_type, header_len, expected_crc, crc;
+	size_t header_end;
+	const u8 *header;
+
+	if (check_add_overflow(header_offset, EFX_SNICBUNDLE_HEADER_LEN,
+			       &header_end))
+		return false;
+	if (fw->size < header_end)
+		return false;
+
+	header = fw->data + header_offset;
+	magic = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_MAGIC_OFST);
+	if (magic != EFX_SNICBUNDLE_HEADER_MAGIC_VALUE)
+		return false;
+
+	version = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_VERSION_OFST);
+	if (version != EFX_SNICBUNDLE_HEADER_VERSION_VALUE)
+		return false;
+
+	bundle_type = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_BUNDLE_TYPE_OFST);
+	if (bundle_type != NVRAM_PARTITION_TYPE_BUNDLE)
+		return false;
+
+	header_len = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_LENGTH_OFST);
+	if (header_len != EFX_SNICBUNDLE_HEADER_LEN)
+		return false;
+
+	expected_crc = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_CRC_OFST);
+	crc = ~crc32_le(~0, header, EFX_SNICBUNDLE_HEADER_CRC_OFST);
+	if (crc != expected_crc)
+		return false;
+
+	*partition_type = NVRAM_PARTITION_TYPE_BUNDLE;
+	*partition_subtype = get_unaligned_le32(header + EFX_SNICBUNDLE_HEADER_BUNDLE_SUBTYPE_OFST);
+	*data = fw->data;
+	*data_size = fw->size;
+	return true;
+}
+
+/* Try to find a valid firmware payload in the firmware data.
+ * When we recognise a valid header, we parse it for the partition type
+ * (so we know where to ask the MC to write it to) and the location of
+ * the data blob to write.
+ */
+static int efx_reflash_parse_firmware_data(const struct firmware *fw,
+					   u32 *partition_type,
+					   u32 *partition_subtype,
+					   const u8 **data, size_t *data_size)
+{
+	size_t header_offset;
+	u32 type, subtype;
+
+	/* Some packaging formats (such as CMS/PKCS#7 signed images)
+	 * prepend a header for which finding the size is a non-trivial
+	 * task, so step through the firmware data until we find a valid
+	 * header.
+	 *
+	 * The checks are intended to reject firmware data that is clearly not
+	 * in the expected format.  They do not need to be exhaustive as the
+	 * running firmware will perform its own comprehensive validity and
+	 * compatibility checks during the update procedure.
+	 *
+	 * Firmware packages may contain multiple reflash images, e.g. a
+	 * bundle containing one or more other images.  Only check the
+	 * outermost container by stopping after the first candidate image
+	 * found even it is for an unsupported partition type.
+	 */
+	for (header_offset = 0; header_offset < fw->size; header_offset++) {
+		if (efx_reflash_parse_snic_bundle_header(fw, header_offset,
+							 partition_type,
+							 partition_subtype,
+							 data, data_size))
+			return 0;
+
+		if (efx_reflash_parse_snic_header(fw, header_offset,
+						  partition_type,
+						  partition_subtype, data,
+						  data_size))
+			return 0;
+
+		if (efx_reflash_parse_reflash_header(fw, header_offset, &type,
+						     &subtype, data, data_size))
+			return efx_reflash_partition_type(type, subtype,
+							  partition_type,
+							  partition_subtype);
+	}
+
+	return -EINVAL;
+}
+
+int efx_reflash_flash_firmware(struct efx_nic *efx, const struct firmware *fw,
+			       struct netlink_ext_ack *extack)
+{
+	struct devlink *devlink = efx->devlink;
+	u32 type, data_subtype;
+	size_t data_size;
+	const u8 *data;
+	int rc;
+
+	if (!efx_has_cap(efx, BUNDLE_UPDATE)) {
+		NL_SET_ERR_MSG_MOD(extack, "NVRAM bundle updates are not supported by the firmware");
+		return -EOPNOTSUPP;
+	}
+
+	devlink_flash_update_status_notify(devlink, "Checking update", NULL, 0, 0);
+
+	rc = efx_reflash_parse_firmware_data(fw, &type, &data_subtype, &data,
+					     &data_size);
+	if (rc) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Firmware image validation check failed");
+		goto out;
+	}
+
+	rc = -EOPNOTSUPP;
+
+out:
+	devlink_flash_update_status_notify(devlink, rc ? "Update failed" :
+							 "Update complete",
+					   NULL, 0, 0);
+	return rc;
+}

drivers/net/ethernet/sfc/efx_reflash.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/****************************************************************************
+ * Driver for AMD network controllers and boards
+ * Copyright (C) 2025, Advanced Micro Devices, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#ifndef _EFX_REFLASH_H
+#define _EFX_REFLASH_H
+
+#include "net_driver.h"
+#include <linux/firmware.h>
+
+int efx_reflash_flash_firmware(struct efx_nic *efx, const struct firmware *fw,
+			       struct netlink_ext_ack *extack);
+
+#endif /* _EFX_REFLASH_H */