bios: add command returning card-detect pin status

litex/soc/software/bios/cmds/cmd_litesdcard.c

@@ -10,6 +10,22 @@
 #include "../command.h"
 #include "../helpers.h"
 
+/**
+ * Command "sdcard_detect"
+ *
+ * Detect SDcard
+ *
+ */
+#ifdef CSR_SDPHY_BASE
+static void sdcard_detect_handler(int nb_params, char **params)
+{
+	uint8_t cd = sdphy_card_detect_read();
+	printf("SDCard %sinserted.\n", cd ? "not " : "");
+}
+
+define_command(sdcard_detect, sdcard_detect_handler, "Detect SDCard", LITESDCARD_CMDS);
+#endif
+
 /**
  * Command "sdcard_init"
  *