diff --git a/ipc.h b/ipc.h
index 263ce36..1470bda 100644
--- a/ipc.h
+++ b/ipc.h
@@ -68,12 +68,8 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #define IPC_SDMMC_ACK	0x0000
 #define IPC_SDMMC_READ	0x0001
 #define IPC_SDMMC_WRITE	0x0002
-/*#define IPC_SD_MOUNT	0x0000
-#define IPC_SD_SELECT	0x0001
-#define IPC_SD_GETSTATE	0x0002
-#define IPC_SD_READ	0x0003
-#define IPC_SD_WRITE	0x0004
-#define IPC_SD_GETSIZE	0x0005*/
+#define IPC_SDMMC_STATE 0x0003
+#define IPC_SDMMC_SIZE	0x0004
 
 #define IPC_KEYS_GETOTP	0x0000
 #define IPC_KEYS_GETEEP	0x0001
diff --git a/sdmmc.c b/sdmmc.c
index d8b4257..e4ae424 100644
--- a/sdmmc.c
+++ b/sdmmc.c
@@ -444,6 +444,75 @@ int sdmmc_write(struct device *dev, u32 blk_start, u32 blk_count, void *data)
 	return 0;
 }
 
+int sdmmc_get_sectors(struct device *dev)
+{
+	int no = (int)dev;
+	struct sdmmc_card *c = &cards[no];
+	struct sdmmc_command cmd;
+	u8 *resp;
+
+	if (c->inserted == 0) {
+		gecko_printf("sdmmc: READ: no card inserted.\n");
+		return -1;
+	}
+
+	if (c->selected == 0) {
+		if (sdmmc_select(dev) < 0) {
+			gecko_printf("sdmmc: READ: cannot select card.\n");
+			return -1;
+		}
+	}
+
+	if (c->new_card == 1) {
+		gecko_printf("sdmmc: new card inserted but not acknowledged yet.\n");
+		return -1;
+	}
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.c_opcode = MMC_SEND_CSD;
+	cmd.c_arg = ((u32)c->rca)<<16;
+	cmd.c_flags = SCF_RSP_R2;
+	sdmmc_host_exec_command(c, &cmd);
+	if (cmd.c_error) {
+		gecko_printf("sdmmc: MMC_SEND_CSD failed for "
+				"card %d with %d", no, cmd.c_error);
+		return -1;
+	}
+
+	resp = (u8 *)cmd.c_resp;
+
+	int num_sectors;
+
+	if (resp[13] == 0xe) { // sdhc
+		unsigned int c_size = resp[7] << 16 | resp[6] << 8 | resp[5];
+//		sdhc_error(sdhci->reg_base, "sdhc mode, c_size=%u, card size = %uk", c_size, (c_size + 1)* 512);
+//		sdhci->timeout = 250 * 1000000; // spec says read timeout is 100ms and write/erase timeout is 250ms
+		num_sectors = (c_size + 1) * 1024; // number of 512-byte sectors
+		}
+	else {
+		unsigned int taac, nsac, read_bl_len, c_size, c_size_mult;
+		taac = resp[13];
+		nsac = resp[12];
+		read_bl_len = resp[9] & 0xF;
+		
+		c_size = (resp[8] & 3) << 10;
+		c_size |= (resp[7] << 2);
+		c_size |= (resp[6] >> 6);
+		c_size_mult = (resp[5] & 3) << 1;
+		c_size_mult |= resp[4] >> 7;
+//		sdhc_error(sdhci->reg_base, "taac=%u nsac=%u read_bl_len=%u c_size=%u c_size_mult=%u card size=%u bytes",
+//			taac, nsac, read_bl_len, c_size, c_size_mult, (c_size + 1) * (4 << c_size_mult) * (1 << read_bl_len));
+//		static const unsigned int time_unit[] = {1, 10, 100, 1000, 10000, 100000, 1000000, 10000000};
+//		static const unsigned int time_value[] = {1, 10, 12, 13, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80}; // must div by 10
+//		sdhci->timeout = time_unit[taac & 7] * time_value[(taac >> 3) & 0xf] / 10;
+//		sdhc_error(sdhci->reg_base, "calculated timeout =  %uns", sdhci->timeout);
+		num_sectors = (c_size + 1) * (4 << c_size_mult) * (1 << read_bl_len) / 512;
+	}
+//	sdhc_error(sdhci->reg_base, "num sectors = %u", sdhci->num_sectors);
+	
+	return num_sectors;
+}
+
 void sdmmc_ipc(volatile ipc_request *req)
 {
 	int ret;
@@ -466,6 +535,14 @@ void sdmmc_ipc(volatile ipc_request *req)
 				req->args[1], (void *)req->args[2]);
 		ipc_post(req->code, req->tag, 1, ret);
 		break;
+	case IPC_SDMMC_STATE:
+		ipc_post(req->code, req->tag, 1,
+				sdmmc_check_card(SDMMC_DEFAULT_DEVICE));
+		break;
+	case IPC_SDMMC_SIZE:
+		ipc_post(req->code, req->tag, 1,
+				sdmmc_get_sectors(SDMMC_DEFAULT_DEVICE));
+		break;
 	}
 }