sandbox: Add a way to skip time delays

Some tests are slow due to delays which are unnecessary on sandbox. The
worst offender is USB where we lose two seconds. Add a way to disable time
delays.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/sandbox/cpu/cpu.c

@@ -37,7 +37,10 @@ void sandbox_exit(void)
 /* delay x useconds */
 void __udelay(unsigned long usec)
 {
-	os_usleep(usec);
+	struct sandbox_state *state = state_get_current();
+
+	if (!state->skip_delays)
+		os_usleep(usec);
 }
 
 int cleanup_before_linux(void)

arch/sandbox/cpu/state.c

@@ -337,6 +337,20 @@ struct sandbox_state *state_get_current(void)
 	return state;
 }
 
+void state_set_skip_delays(bool skip_delays)
+{
+	struct sandbox_state *state = state_get_current();
+
+	state->skip_delays = skip_delays;
+}
+
+bool state_get_skip_delays(void)
+{
+	struct sandbox_state *state = state_get_current();
+
+	return state->skip_delays;
+}
+
 int state_init(void)
 {
 	state = &main_state;

arch/sandbox/include/asm/state.h

@@ -63,6 +63,7 @@ struct sandbox_state {
 	enum reset_t last_reset;	/* Last reset type */
 	bool reset_allowed[RESET_COUNT];	/* Allowed reset types */
 	enum state_terminal_raw term_raw;	/* Terminal raw/cooked */
+	bool skip_delays;		/* Ignore any time delays (for test) */
 
 	/* Pointer to information for each SPI bus/cs */
 	struct sandbox_spi_info spi[CONFIG_SANDBOX_SPI_MAX_BUS]
@@ -184,6 +185,24 @@ int sandbox_write_state(struct sandbox_state *state, const char *fname);
  */
 int state_setprop(int node, const char *prop_name, const void *data, int size);
 
+/**
+ * Control skipping of time delays
+ *
+ * Some tests have unnecessay time delays (e.g. USB). Allow these to be
+ * skipped to speed up testing
+ *
+ * @param skip_delays	true to skip delays from now on, false to honour delay
+ *			requests
+ */
+void state_set_skip_delays(bool skip_delays);
+
+/**
+ * See if delays should be skipped
+ *
+ * @return true if delays should be skipped, false if they should be honoured
+ */
+bool state_get_skip_delays(void);
+
 /**
  * Initialize the test system state
  */