sandbox: Add an option to display of-platdata in SPL

At present we don't have a test that of-platdata can be accessed in SPL.
Add this in as a command-line option to SPL.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/cpu/spl.c b/arch/sandbox/cpu/spl.c
index 42c149a..49f9864 100644
--- a/arch/sandbox/cpu/spl.c
+++ b/arch/sandbox/cpu/spl.c
@@ -44,5 +44,19 @@
 
 void spl_board_init(void)
 {
+	struct sandbox_state *state = state_get_current();
+	struct udevice *dev;
+
 	preloader_console_init();
+	if (state->show_of_platdata) {
+		/*
+		 * Scan all the devices so that we can output their platform
+		 * data. See sandbox_spl_probe().
+		 */
+		printf("Scanning misc devices\n");
+		for (uclass_first_device(UCLASS_MISC, &dev);
+		     dev;
+		     uclass_next_device(&dev))
+			;
+	}
 }
diff --git a/arch/sandbox/cpu/start.c b/arch/sandbox/cpu/start.c
index 2ee3b48..28ca353 100644
--- a/arch/sandbox/cpu/start.c
+++ b/arch/sandbox/cpu/start.c
@@ -283,6 +283,15 @@
 SANDBOX_CMDLINE_OPT_SHORT(log_level, 'L', 1,
 			  "Set log level (0=panic, 7=debug)");
 
+static int sandbox_cmdline_cb_show_of_platdata(struct sandbox_state *state,
+					       const char *arg)
+{
+	state->show_of_platdata = true;
+
+	return 0;
+}
+SANDBOX_CMDLINE_OPT(show_of_platdata, 0, "Show of-platdata in SPL");
+
 int board_run_command(const char *cmdline)
 {
 	printf("## Commands are disabled. Please enable CONFIG_CMDLINE.\n");
diff --git a/arch/sandbox/cpu/u-boot-spl.lds b/arch/sandbox/cpu/u-boot-spl.lds
index f97abdf..de65b01 100644
--- a/arch/sandbox/cpu/u-boot-spl.lds
+++ b/arch/sandbox/cpu/u-boot-spl.lds
@@ -14,7 +14,7 @@
 	}
 
 	__u_boot_sandbox_option_start = .;
-	_u_boot_sandbox_getopt : { *(.u_boot_sandbox_getopt) }
+	_u_boot_sandbox_getopt : { KEEP(*(.u_boot_sandbox_getopt)) }
 	__u_boot_sandbox_option_end = .;
 
 	__bss_start = .;
diff --git a/arch/sandbox/include/asm/state.h b/arch/sandbox/include/asm/state.h
index dcb6d5f..0a2e3c4 100644
--- a/arch/sandbox/include/asm/state.h
+++ b/arch/sandbox/include/asm/state.h
@@ -89,6 +89,7 @@
 	bool skip_delays;		/* Ignore any time delays (for test) */
 	bool show_test_output;		/* Don't suppress stdout in tests */
 	int default_log_level;		/* Default log level for sandbox */
+	bool show_of_platdata;		/* Show of-platdata in SPL */
 
 	/* Pointer to information for each SPI bus/cs */
 	struct sandbox_spi_info spi[CONFIG_SANDBOX_SPI_MAX_BUS]