exo: add smcAmsGetEmummcConfig

exosphere/src/smc_ams.c

@@ -13,8 +13,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
- 
- 
+
+
 #include <stdatomic.h>
 #include <stdbool.h>
 #include <stdint.h>
@@ -26,6 +26,8 @@
 #include "synchronization.h"
 #include "memory_map.h"
 #include "mmu.h"
+#include "userpage.h"
+#include "exocfg.h"
 
 static atomic_flag g_ams_userpage_mapped = ATOMIC_FLAG_INIT;
 static atomic_flag g_ams_iram_page_mapped = ATOMIC_FLAG_INIT;
@@ -94,42 +96,42 @@ uint32_t ams_iram_copy(smc_args_t *args) {
     /* args->X[2] = IRAM address, must be 4-byte aligned. */
     /* args->X[3] = size (must be <= 0x1000 and 4-byte aligned). */
     /* args->X[4] = 0 for read, 1 for write. */
-    
+
     const uintptr_t dram_address = (uintptr_t)args->X[1];
     const uintptr_t iram_address = (uintptr_t)args->X[2];
     const uintptr_t dram_page_offset = (dram_address & 0xFFFULL);
     const uintptr_t iram_page_offset = (iram_address & 0xFFFULL);
     const size_t size = args->X[3];
     const uint32_t option = (uint32_t)args->X[4];
-            
+
     /* Validate addresses. */
     if (!ams_is_user_addr_valid(dram_address) || !ams_is_iram_addr_valid(iram_address)) {
         return 2;
     }
-    
+
     /* Validate size. */
     if (size > 0x1000 || (size + dram_page_offset) > 0x1000 || (size + iram_page_offset) > 0x1000) {
         return 2;
     }
-    
+
     /* Validate alignment. */
     if (size % sizeof(uint32_t) || dram_page_offset % sizeof(uint32_t) || iram_page_offset % sizeof(uint32_t)) {
         return 2;
     }
-    
+
     /* Validate argument. */
     if (option != 0 && option != 1) {
         return 2;
     }
-    
+
     /* Map pages. */
     ams_map_userpage(dram_address);
     ams_map_irampage(iram_address);
-    
+
     /* Set source/destination for copy. */
     volatile uint32_t *dram_ptr = (volatile uint32_t *)(AMS_USER_PAGE_SECURE_MONITOR_ADDR + dram_page_offset);
     volatile uint32_t *iram_ptr = (volatile uint32_t *)(AMS_IRAM_PAGE_SECURE_MONITOR_ADDR + iram_page_offset);
-    
+
     volatile uint32_t *dst;
     volatile uint32_t *src;
     const size_t num_dwords = size / sizeof(uint32_t);
@@ -140,19 +142,19 @@ uint32_t ams_iram_copy(smc_args_t *args) {
         dst = iram_ptr;
         src = dram_ptr;
     }
-    
+
     /* Actually copy data. */
     for (size_t i = 0; i < num_dwords; i++) {
         dst[i] = src[i];
     }
-    
+
     /* Flush! */
-    flush_dcache_range((void *)dst, (void *)(dst + num_dwords));    
-    
+    flush_dcache_range((void *)dst, (void *)(dst + num_dwords));
+
     /* Unmap pages. */
     ams_unmap_irampage();
     ams_unmap_userpage();
-    
+
     return 0;
 }
 
@@ -222,3 +224,50 @@ uint32_t ams_write_address(smc_args_t *args) {
 
     return 0;
 }
+
+uint32_t ams_get_emummc_config(smc_args_t *args) {
+    /* This retrieves configuration for the current emummc context. */
+    /* args->X[1] = MMC id, must be size-bytes aligned and readable by EL0. */
+    /* args->X[2] = Pointer to output (for path for filebased), must be at least 0x80 bytes. */
+    upage_ref_t page_ref;
+    const uint32_t mmc_id = (uint32_t)args->X[1];
+    void *user_address = (void *)args->X[2];
+    const exo_emummc_config_t *emummc_cfg = exosphere_get_emummc_config();
+
+    if (mmc_id != EMUMMC_MMC_NAND) {
+        /* Emummc config for non-NAND storage is not yet implemented. */
+        return 1;
+    }
+
+    if (emummc_cfg->base_cfg.type == EMUMMC_TYPE_NONE) {
+        /* Just copy base config. */
+        memset(args, 0, sizeof(*args));
+        memcpy(&args->X[1], emummc_cfg, sizeof(emummc_cfg->base_cfg));
+        _Static_assert(sizeof(emummc_cfg->base_cfg) <= sizeof(*args) - sizeof(args->X[0]), "Emunand base config too big!");
+        return 0;
+    } else if (emummc_cfg->base_cfg.type == EMUMMC_TYPE_PARTITION) {
+        /* Copy base config and partition config. */
+        memset(args, 0, sizeof(*args));
+        memcpy(&args->X[1], emummc_cfg, sizeof(emummc_cfg->base_cfg) + sizeof(emummc_cfg->partition_cfg));
+        _Static_assert(sizeof(emummc_cfg->base_cfg) + sizeof(emummc_cfg->partition_cfg) <= sizeof(*args) - sizeof(args->X[0]), "Emunand partition config too big!");
+        return 0;
+    } else if (emummc_cfg->base_cfg.type == EMUMMC_TYPE_FILES) {
+        /* Copy path to userpage. */
+        /* Initialize page reference. */
+        if (upage_init(&page_ref, user_address) == 0) {
+            return 2;
+        }
+        /* Copy result output back to user. */
+        if (secure_copy_to_user(&page_ref, user_address, &emummc_cfg->file_cfg, sizeof(emummc_cfg->file_cfg)) == 0) {
+            return 2;
+        }
+
+        /* Copy base config afterwards, since this can't fail. */
+        memset(args, 0, sizeof(*args));
+        memcpy(&args->X[1], emummc_cfg, sizeof(emummc_cfg->base_cfg));
+        _Static_assert(sizeof(emummc_cfg->base_cfg) <= sizeof(*args) - sizeof(args->X[0]), "Emunand base config too big!");
+        return 0;
+    } else {
+        return 2;
+    }
+}