multiboot: Allow searching in volume 0 for redirect file

Searching in volume 0 is necessary for multiboot targets with only
one drive, like the M3K/Q1/ErosQ. Without this the search code will
never look at the redirect file on these targets.

The search bound is configured with a setting MULTIBOOT_MIN_VOLUME,
which defaults to 0, but is defined to 1 for Sansa players so they
keep their old behavior.

Change-Id: I6dc5cf98db4258731de2c68c3ab1182b4a4a655b

1 files changed, 6 insertions, 0 deletions

diff --git a/firmware/export/config.h b/firmware/export/config.h
index 7002b2a3c5..6465bdcb0e 100644
--- a/firmware/export/config.h
+++ b/firmware/export/config.h
@@ -869,6 +869,12 @@ Lyre prototype 1 */
 #define HAVE_MULTIBOOT
 #endif
 
+/* The lowest numbered volume to read a multiboot redirect from; default is to
+ * allow any volume but some targets may wish to exclude the internal drive. */
+#if defined(HAVE_MULTIBOOT) && !defined(MULTIBOOT_MIN_VOLUME)
+# define MULTIBOOT_MIN_VOLUME 0
+#endif
+
 #ifndef NUM_DRIVES
 #define NUM_DRIVES 1
 #endif