Cleanups

Replace a printf with a DBG in timer_rtdsc.c
Replace a printf in timer.c with assert
Return proper error codes from timer drivers

Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>

src/arch/i386/drivers/timer_rtdsc.c

 
 #include <gpxe/init.h>
 #include <gpxe/timer.h>
+#include <errno.h>
 #include <stdio.h>
 #include <bits/cpu.h>
 #include <bits/timer2.h>
 		}
 	}
 
-	printf("RTDSC timer not available on this machine.\n");
-	return 1;
+	DBG("RTDSC timer not available on this machine.\n");
+	return -ENODEV;
 }
 
 struct timer rtdsc_ts __timer (01) = {

src/arch/i386/include/bits/errfile.h

 #define ERRFILE_undionly	 ( ERRFILE_ARCH | ERRFILE_NET | 0x00030000 )
 #define ERRFILE_undirom		 ( ERRFILE_ARCH | ERRFILE_NET | 0x00040000 )
 
+#define ERRFILE_timer_rtdsc    ( ERRFILE_ARCH | ERRFILE_DRIVER | 0x00000000 )
+#define ERRFILE_timer_bios     ( ERRFILE_ARCH | ERRFILE_DRIVER | 0x00010000 )
+
 /** @} */
 
 #endif /* _BITS_ERRFILE_H */

src/core/timer.c

 	struct timer *ts;
 
 	for (ts = ts_table; ts < ts_table_end; ts++) {
-		if (ts->init && !ts->init()) {
+		if (ts->init && ts->init() >= 0) {
 			used_ts = ts;
 			break;
 		}
 	}
 
-	if (!used_ts) {
-		printf("No timer available. This should never happen. Expect gPXE to die soon.\n");
-		/* Panic */
-	}
-
+	assert(used_ts);
 }
 
 struct init_fn ts_init_fn __init_fn ( INIT_NORMAL ) = {