diff --git a/hw/sd/sdmmc-internal.h b/hw/sd/sdmmc-internal.h
index d8bf17d204..306ffa7f53 100644
--- a/hw/sd/sdmmc-internal.h
+++ b/hw/sd/sdmmc-internal.h
@@ -11,6 +11,103 @@
 #ifndef SDMMC_INTERNAL_H
 #define SDMMC_INTERNAL_H
 
+/*
+ * EXT_CSD fields
+ */
+
+#define EXT_CSD_CMDQ_MODE_EN            15      /* R/W */
+#define EXT_CSD_FLUSH_CACHE             32      /* W */
+#define EXT_CSD_CACHE_CTRL              33      /* R/W */
+#define EXT_CSD_POWER_OFF_NOTIFICATION  34      /* R/W */
+#define EXT_CSD_PACKED_FAILURE_INDEX    35      /* RO */
+#define EXT_CSD_PACKED_CMD_STATUS       36      /* RO */
+#define EXT_CSD_EXP_EVENTS_STATUS       54      /* RO, 2 bytes */
+#define EXT_CSD_EXP_EVENTS_CTRL         56      /* R/W, 2 bytes */
+#define EXT_CSD_DATA_SECTOR_SIZE        61      /* R */
+#define EXT_CSD_GP_SIZE_MULT            143     /* R/W */
+#define EXT_CSD_PARTITION_SETTING_COMPLETED 155 /* R/W */
+#define EXT_CSD_PARTITION_ATTRIBUTE     156     /* R/W */
+#define EXT_CSD_PARTITION_SUPPORT       160     /* RO */
+#define EXT_CSD_HPI_MGMT                161     /* R/W */
+#define EXT_CSD_RST_N_FUNCTION          162     /* R/W */
+#define EXT_CSD_BKOPS_EN                163     /* R/W */
+#define EXT_CSD_BKOPS_START             164     /* W */
+#define EXT_CSD_SANITIZE_START          165     /* W */
+#define EXT_CSD_WR_REL_PARAM            166     /* RO */
+#define EXT_CSD_RPMB_MULT               168     /* RO */
+#define EXT_CSD_FW_CONFIG               169     /* R/W */
+#define EXT_CSD_BOOT_WP                 173     /* R/W */
+#define EXT_CSD_ERASE_GROUP_DEF         175     /* R/W */
+#define EXT_CSD_PART_CONFIG             179     /* R/W */
+#define EXT_CSD_ERASED_MEM_CONT         181     /* RO */
+#define EXT_CSD_BUS_WIDTH               183     /* R/W */
+#define EXT_CSD_STROBE_SUPPORT          184     /* RO */
+#define EXT_CSD_HS_TIMING               185     /* R/W */
+#define EXT_CSD_POWER_CLASS             187     /* R/W */
+#define EXT_CSD_REV                     192     /* RO */
+#define EXT_CSD_STRUCTURE               194     /* RO */
+#define EXT_CSD_CARD_TYPE               196     /* RO */
+#define EXT_CSD_DRIVER_STRENGTH         197     /* RO */
+#define EXT_CSD_OUT_OF_INTERRUPT_TIME   198     /* RO */
+#define EXT_CSD_PART_SWITCH_TIME        199     /* RO */
+#define EXT_CSD_PWR_CL_52_195           200     /* RO */
+#define EXT_CSD_PWR_CL_26_195           201     /* RO */
+#define EXT_CSD_PWR_CL_52_360           202     /* RO */
+#define EXT_CSD_PWR_CL_26_360           203     /* RO */
+#define EXT_CSD_SEC_CNT                 212     /* RO, 4 bytes */
+#define EXT_CSD_S_A_TIMEOUT             217     /* RO */
+#define EXT_CSD_S_C_VCCQ                219     /* RO */
+#define EXT_CSD_S_C_VCC                 220     /* RO */
+#define EXT_CSD_REL_WR_SEC_C            222     /* RO */
+#define EXT_CSD_HC_WP_GRP_SIZE          221     /* RO */
+#define EXT_CSD_ERASE_TIMEOUT_MULT      223     /* RO */
+#define EXT_CSD_HC_ERASE_GRP_SIZE       224     /* RO */
+#define EXT_CSD_ACC_SIZE                225     /* RO */
+#define EXT_CSD_BOOT_MULT               226     /* RO */
+#define EXT_CSD_BOOT_INFO               228     /* RO */
+#define EXT_CSD_SEC_TRIM_MULT           229     /* RO */
+#define EXT_CSD_SEC_ERASE_MULT          230     /* RO */
+#define EXT_CSD_SEC_FEATURE_SUPPORT     231     /* RO */
+#define EXT_CSD_TRIM_MULT               232     /* RO */
+#define EXT_CSD_PWR_CL_200_195          236     /* RO */
+#define EXT_CSD_PWR_CL_200_360          237     /* RO */
+#define EXT_CSD_PWR_CL_DDR_52_195       238     /* RO */
+#define EXT_CSD_PWR_CL_DDR_52_360       239     /* RO */
+#define EXT_CSD_BKOPS_STATUS            246     /* RO */
+#define EXT_CSD_POWER_OFF_LONG_TIME     247     /* RO */
+#define EXT_CSD_GENERIC_CMD6_TIME       248     /* RO */
+#define EXT_CSD_CACHE_SIZE              249     /* RO, 4 bytes */
+#define EXT_CSD_PWR_CL_DDR_200_360      253     /* RO */
+#define EXT_CSD_FIRMWARE_VERSION        254     /* RO, 8 bytes */
+#define EXT_CSD_PRE_EOL_INFO            267     /* RO */
+#define EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A      268     /* RO */
+#define EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_B      269     /* RO */
+#define EXT_CSD_CMDQ_DEPTH              307     /* RO */
+#define EXT_CSD_CMDQ_SUPPORT            308     /* RO */
+#define EXT_CSD_SUPPORTED_MODE          493     /* RO */
+#define EXT_CSD_TAG_UNIT_SIZE           498     /* RO */
+#define EXT_CSD_DATA_TAG_SUPPORT        499     /* RO */
+#define EXT_CSD_MAX_PACKED_WRITES       500     /* RO */
+#define EXT_CSD_MAX_PACKED_READS        501     /* RO */
+#define EXT_CSD_BKOPS_SUPPORT           502     /* RO */
+#define EXT_CSD_HPI_FEATURES            503     /* RO */
+#define EXT_CSD_S_CMD_SET               504     /* RO */
+
+/*
+ * EXT_CSD field definitions
+ */
+
+#define EXT_CSD_WR_REL_PARAM_EN         (1 << 2)
+#define EXT_CSD_WR_REL_PARAM_EN_RPMB_REL_WR     (1 << 4)
+
+#define EXT_CSD_PART_CONFIG_ACC_MASK    (0x7)
+#define EXT_CSD_PART_CONFIG_ACC_DEFAULT (0x0)
+#define EXT_CSD_PART_CONFIG_ACC_BOOT0   (0x1)
+
+#define EXT_CSD_PART_CONFIG_EN_MASK     (0x7 << 3)
+#define EXT_CSD_PART_CONFIG_EN_BOOT0    (0x1 << 3)
+#define EXT_CSD_PART_CONFIG_EN_USER     (0x7 << 3)
+
 #define SDMMC_CMD_MAX 64
 
 /**
