diff --git a/src/kboot.c b/src/kboot.c
index a0656dc7..cca409cc 100644
--- a/src/kboot.c
+++ b/src/kboot.c
@@ -1841,23 +1841,17 @@ static int dt_set_display(void)
     return dt_vram_reserved_region(disp_cfg->dcp_alias, "disp0");
 }
 
-static int dt_set_sio_fwdata(void)
+static int dt_set_sio_fwdata(const char *adt_path, const char *fdt_alias)
 {
-    const char *path = "sio";
-
-    int node = fdt_path_offset(dt, path);
+    int node = fdt_path_offset(dt, fdt_alias);
     if (node < 0) {
-        printf("FDT: '%s' node not found\n", path);
+        printf("FDT: '%s' node not found\n", fdt_alias);
         return 0;
     }
 
-    int ret = sio_setup_fwdata();
-    if (ret < 0)
-        bail("FDT: failed to set up SIO firmware data: %d\n", ret);
-
     int phandle = fdt_get_phandle(dt, node);
     uint32_t max_phandle;
-    ret = fdt_find_max_phandle(dt, &max_phandle);
+    int ret = fdt_find_max_phandle(dt, &max_phandle);
     if (ret)
         bail("FDT: failed to get max phandle: %d\n", ret);
 
@@ -1865,11 +1859,15 @@ static int dt_set_sio_fwdata(void)
         phandle = ++max_phandle;
         ret = fdt_setprop_u32(dt, node, "phandle", phandle);
         if (ret != 0)
-            bail("FDT: couldn't set '%s.phandle' property: %d\n", path, ret);
+            bail("FDT: couldn't set '%s.phandle' property: %d\n", fdt_alias, ret);
     }
 
-    for (int i = 0; i < sio_num_fwdata; i++) {
-        struct sio_mapping *mapping = &sio_fwdata[i];
+    struct sio_data *siodata = sio_setup_fwdata(adt_path);
+    if (!siodata)
+        bail("FDT: failed to set up SIO(%s) firmware data\n", adt_path);
+
+    for (int i = 0; i < siodata->num_fwdata; i++) {
+        struct sio_mapping *mapping = &siodata->fwdata[i];
 
         char node_name[64];
         snprintf(node_name, sizeof(node_name), "sio-firmware-data@%lx", mapping->phys);
@@ -1885,23 +1883,50 @@ static int dt_set_sio_fwdata(void)
         if (ret < 0)
             return ret;
 
-        ret = dt_device_add_mem_region(path, mem_phandle, NULL);
+        ret = dt_device_add_mem_region(fdt_alias, mem_phandle, NULL);
         if (ret < 0)
             return ret;
     }
 
-    node = fdt_path_offset(dt, path);
+    node = fdt_path_offset(dt, fdt_alias);
     if (node < 0)
-        bail("FDT: '%s' not found\n", path);
+        bail_cleanup("FDT: '%s' not found\n", fdt_alias);
 
-    for (int i = 0; i < sio_num_fwparams; i++) {
-        struct sio_fwparam *param = &sio_fwparams[i];
+    for (int i = 0; i < siodata->num_fwparams; i++) {
+        struct sio_fwparam *param = &siodata->fwparams[i];
 
         if (fdt_appendprop_u32(dt, node, "apple,sio-firmware-params", param->key))
-            bail("FDT: couldn't append to SIO parameters\n");
+            bail_cleanup("FDT: couldn't append to SIO parameters\n");
 
         if (fdt_appendprop_u32(dt, node, "apple,sio-firmware-params", param->value))
-            bail("FDT: couldn't append to SIO parameters\n");
+            bail_cleanup("FDT: couldn't append to SIO parameters\n");
+    }
+
+err:
+    free(siodata);
+    return 0;
+}
+
+static int dt_setup_sio(void)
+{
+    static const char *sio_names[2] = {"sio", "sio1"};
+
+    for (size_t i = 0; i < ARRAY_SIZE(sio_names); i++) {
+
+        int node = fdt_path_offset(dt, sio_names[i]);
+        if (node < 0)
+            continue;
+
+        char adt_path[16];
+        snprintf(adt_path, sizeof(adt_path), "/arm-io/%s", sio_names[i]);
+
+        if (dt_reserve_asc_firmware(adt_path, NULL, sio_names[i], true, 0))
+            continue;
+        if (dt_set_sio_fwdata(adt_path, sio_names[i]))
+            continue;
+
+        node = fdt_path_offset(dt, sio_names[i]);
+        fdt_setprop_string(dt, node, "status", "okay");
     }
 
     return 0;
@@ -2294,9 +2319,7 @@ int kboot_prepare_dt(void *fdt)
         return -1;
     if (dt_disable_missing_devs("i2c", "i2c@", 8))
         return -1;
-    if (dt_reserve_asc_firmware("/arm-io/sio", NULL, "sio", true, 0))
-        return -1;
-    if (dt_set_sio_fwdata())
+    if (dt_setup_sio())
         return -1;
     if (dt_reserve_asc_firmware("/arm-io/isp", "/arm-io/isp0", "isp", false, isp_iova_base()))
         return -1;
diff --git a/src/sio.c b/src/sio.c
index 0008d9c3..150d8305 100644
--- a/src/sio.c
+++ b/src/sio.c
@@ -13,23 +13,16 @@
 #define SIO_KEY(s)  _SIO_KEY(#s)
 #define _SIO_KEY(s) (((s)[0] << 24) | ((s)[1] << 16) | ((s)[2] << 8) | (s)[3])
 
-#define MAX_FWDATA   6
-#define MAX_FWPARAMS 16
-
-int sio_num_fwdata;
-struct sio_mapping *sio_fwdata;
-int sio_num_fwparams;
-struct sio_fwparam *sio_fwparams;
-
-static void *alloc_mapped_data(size_t size, u64 *iova)
+static void *alloc_mapped_data(struct sio_data *siodata, size_t size, u64 *iova)
 {
-    if (sio_num_fwdata >= MAX_FWDATA)
+    if (siodata->num_fwdata >= MAX_FWDATA)
         return NULL;
 
-    struct sio_mapping *mapping = &sio_fwdata[sio_num_fwdata];
+    struct sio_mapping *mapping = &siodata->fwdata[siodata->num_fwdata];
 
 #ifdef MERGE_SIO_FWDATA
-    if (sio_num_fwdata && ALIGN_UP((mapping - 1)->size, SZ_16K) >= (mapping - 1)->size + size) {
+    if (siodata->num_fwdata &&
+        ALIGN_UP((mapping - 1)->size, SZ_16K) >= (mapping - 1)->size + size) {
         mapping--;
         *iova = mapping->iova + mapping->size;
         mapping->size = ALIGN_UP(mapping->size + size, SZ_4K);
@@ -37,8 +30,8 @@ static void *alloc_mapped_data(size_t size, u64 *iova)
     }
 #endif
 
-    if (!sio_num_fwdata++)
-        mapping->iova = *iova = 0x30000;
+    if (!siodata->num_fwdata++)
+        mapping->iova = *iova = siodata->iova_base;
     else
         mapping->iova = *iova = ALIGN_UP((mapping - 1)->iova + (mapping - 1)->size, SZ_16K);
     mapping->size = ALIGN_UP(size, SZ_4K);
@@ -49,32 +42,32 @@ done:
     return (void *)((*iova - mapping->iova) + mapping->phys);
 }
 
-static void mapping_fixup(void)
+static void mapping_fixup(struct sio_data *siodata)
 {
-    for (int i = 0; i < sio_num_fwdata; i++) {
-        struct sio_mapping *mapping = &sio_fwdata[i];
+    for (int i = 0; i < siodata->num_fwdata; i++) {
+        struct sio_mapping *mapping = &siodata->fwdata[i];
         mapping->size = ALIGN_UP(mapping->size, SZ_16K);
     }
 }
 
-static void *add_fwdata(size_t size, u32 param_id)
+static void *add_fwdata(struct sio_data *siodata, size_t size, u32 param_id)
 {
-    if (sio_num_fwparams + 1 >= MAX_FWPARAMS)
+    if (siodata->num_fwparams + 1 >= MAX_FWPARAMS)
         return NULL;
 
     u64 iova;
-    void *p = alloc_mapped_data(size, &iova);
+    void *p = alloc_mapped_data(siodata, size, &iova);
 
     if (!p)
         return NULL;
 
-    struct sio_fwparam *param = &sio_fwparams[sio_num_fwparams];
+    struct sio_fwparam *param = &siodata->fwparams[siodata->num_fwparams];
     param->key = param_id;
     param->value = iova >> 12;
     param++;
     param->key = param_id + 1;
     param->value = size;
-    sio_num_fwparams += 2;
+    siodata->num_fwparams += 2;
 
     return p;
 }
@@ -152,29 +145,19 @@ int find_key_index(const char *keylist[], u32 needle)
     return i;
 }
 
-int sio_setup_fwdata(void)
+struct sio_data *sio_setup_fwdata(const char *adt_path)
 {
-    int ret = -ENOMEM;
+    struct sio_data *siodata = calloc(1, sizeof(struct sio_data));
 
-    if (sio_fwdata)
-        return 0;
+    if (!siodata)
+        return NULL;
 
-    sio_fwdata = calloc(MAX_FWDATA, sizeof(*sio_fwdata));
-    if (!sio_fwdata)
-        return -ENOMEM;
-    sio_num_fwdata = 0;
+    siodata->iova_base = 0x30000;
 
-    sio_fwparams = calloc(MAX_FWPARAMS, sizeof(*sio_fwdata));
-    if (!sio_fwparams) {
-        free(sio_fwdata);
-        return -ENOMEM;
-    }
-    sio_num_fwparams = 0;
-
-    int node = adt_path_offset(adt, "/arm-io/sio");
+    int node = adt_path_offset(adt, adt_path);
     if (node < 0) {
-        printf("%s: missing node\n", __func__);
-        goto err_inval;
+        printf("%s: missing node %s\n", __func__, adt_path);
+        goto err;
     }
 
     for (int i = 0; i < (int)ARRAY_SIZE(copy_rules); i++) {
@@ -182,8 +165,8 @@ int sio_setup_fwdata(void)
         u32 len;
 
         if (!rule->prop) {
-            if (!add_fwdata(rule->blobsize, rule->fw_param))
-                goto err_nomem;
+            if (!add_fwdata(siodata, rule->blobsize, rule->fw_param))
+                goto err;
 
             continue;
         }
@@ -191,26 +174,26 @@ int sio_setup_fwdata(void)
         const u8 *adt_blob = adt_getprop(adt, node, rule->prop, &len);
         if (!adt_blob) {
             printf("%s: missing ADT property '%s'\n", __func__, rule->prop);
-            goto err_inval;
+            goto err;
         }
 
         if (!rule->keyed) {
-            u8 *sio_blob = add_fwdata(len, rule->fw_param);
+            u8 *sio_blob = add_fwdata(siodata, len, rule->fw_param);
             if (!sio_blob)
-                goto err_nomem;
+                goto err;
             memcpy8(sio_blob, (void *)adt_blob, len);
             continue;
         }
 
         int nkeys = find_key_index(rule->keys, 0);
-        u8 *sio_blob = add_fwdata(nkeys * rule->blobsize, rule->fw_param);
+        u8 *sio_blob = add_fwdata(siodata, nkeys * rule->blobsize, rule->fw_param);
         if (!sio_blob)
-            goto err_nomem;
+            goto err;
 
         if (len % (rule->blobsize + 4) != 0) {
             printf("%s: bad length %d of ADT property '%s', expected multiple of %d + 4\n",
                    __func__, len, rule->prop, rule->blobsize);
-            goto err_inval;
+            goto err;
         }
 
         for (u32 off = 0; off + rule->blobsize <= len; off += (rule->blobsize + 4)) {
@@ -221,36 +204,26 @@ int sio_setup_fwdata(void)
             if (key_idx >= nkeys) {
                 printf("%s: unknown key %x found in ADT property '%s'\n", __func__, key,
                        rule->prop);
-                goto err_inval;
+                goto err;
             }
 
             memcpy8(sio_blob + (key_idx * rule->blobsize), (void *)(p + 4), rule->blobsize);
         }
     }
 
-    mapping_fixup();
+    mapping_fixup(siodata);
 
-    return 0;
-
-err_inval:
-    ret = -EINVAL;
-    goto err;
-err_nomem:
-    ret = -ENOMEM;
-    goto err;
+    return siodata;
 
 err:
     for (int i = 0; i < MAX_FWDATA; i++) {
-        if (!sio_fwdata[i].size)
+        if (!siodata->fwdata[i].size)
             break;
         // No way to give back memory with the top of memory
         // allocator.
         // free((void *)sio_fwdata[i].phys);
     }
-    free(sio_fwdata);
-    free(sio_fwparams);
-    sio_fwdata = NULL;
-    sio_fwparams = NULL;
+    free(siodata);
 
-    return ret;
+    return NULL;
 }
diff --git a/src/sio.h b/src/sio.h
index be8f63bd..2ad41f57 100644
--- a/src/sio.h
+++ b/src/sio.h
@@ -3,6 +3,8 @@
 #ifndef SIO_H
 #define SIO_H
 
+#include "types.h"
+
 struct sio_mapping {
     u64 phys;
     u64 iova;
@@ -14,11 +16,17 @@ struct sio_fwparam {
     u32 value;
 };
 
-extern int sio_num_fwdata;
-extern struct sio_mapping *sio_fwdata;
-extern int sio_num_fwparams;
-extern struct sio_fwparam *sio_fwparams;
+#define MAX_FWDATA   6
+#define MAX_FWPARAMS 16
 
-int sio_setup_fwdata(void);
+struct sio_data {
+    u64 iova_base;
+    struct sio_mapping fwdata[MAX_FWDATA];
+    struct sio_fwparam fwparams[MAX_FWPARAMS];
+    int num_fwdata;
+    int num_fwparams;
+};
+
+struct sio_data *sio_setup_fwdata(const char *adt_path);
 
 #endif