[src/trunk]: src/sys/dev/fdt Add some helpers to find the stdout device.

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e5a8fe04d425
branches:  trunk
changeset: 823403:e5a8fe04d425
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Fri Apr 21 23:35:01 2017 +0000

description:
Add some helpers to find the stdout device.

diffstat:

 sys/dev/fdt/fdt_subr.c |  56 ++++++++++++++++++++++++++++++++++++++++++++++++-
 sys/dev/fdt/fdtvar.h   |   6 ++++-
 2 files changed, 59 insertions(+), 3 deletions(-)

diffs (92 lines):

diff -r 0f85709b914b -r e5a8fe04d425 sys/dev/fdt/fdt_subr.c
--- a/sys/dev/fdt/fdt_subr.c    Fri Apr 21 23:07:45 2017 +0000
+++ b/sys/dev/fdt/fdt_subr.c    Fri Apr 21 23:35:01 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: fdt_subr.c,v 1.7 2017/04/21 21:08:57 jmcneill Exp $ */
+/* $NetBSD: fdt_subr.c,v 1.8 2017/04/21 23:35:01 jmcneill Exp $ */
 
 /*-
  * Copyright (c) 2015 Jared D. McNeill <jmcneill%invisible.ca@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fdt_subr.c,v 1.7 2017/04/21 21:08:57 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fdt_subr.c,v 1.8 2017/04/21 23:35:01 jmcneill Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -216,3 +216,55 @@
 
        return 0;
 }
+
+const char *
+fdtbus_get_stdout_path(void)
+{
+       const int off = fdt_path_offset(fdtbus_get_data(), "/chosen");
+       if (off < 0)
+               return NULL;
+       
+       return fdt_getprop(fdtbus_get_data(), off, "stdout-path", NULL);
+}
+
+int
+fdtbus_get_stdout_phandle(void)
+{
+       const char *prop, *p;
+       int off, len;
+
+       prop = fdtbus_get_stdout_path();
+       if (prop == NULL)
+               return -1;
+
+       p = strchr(prop, ':');
+       len = p == NULL ? strlen(prop) : (p - prop);
+       if (*prop != '/') {
+               /* Alias */
+               prop = fdt_get_alias_namelen(fdtbus_get_data(), prop, len);
+               if (prop == NULL)
+                       return -1;
+               len = strlen(prop);
+       }
+       off = fdt_path_offset_namelen(fdtbus_get_data(), prop, len);
+       if (off < 0)
+               return -1;
+
+       return fdtbus_offset2phandle(off);
+}
+
+int
+fdtbus_get_stdout_speed(void)
+{
+       const char *prop, *p;
+
+       prop = fdtbus_get_stdout_path();
+       if (prop == NULL)
+               return -1;
+
+       p = strchr(prop, ':');
+       if (p == NULL)
+               return -1;
+
+       return (int)strtoul(p + 1, NULL, 10);
+}
diff -r 0f85709b914b -r e5a8fe04d425 sys/dev/fdt/fdtvar.h
--- a/sys/dev/fdt/fdtvar.h      Fri Apr 21 23:07:45 2017 +0000
+++ b/sys/dev/fdt/fdtvar.h      Fri Apr 21 23:35:01 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: fdtvar.h,v 1.9 2017/04/16 12:24:57 jmcneill Exp $ */
+/* $NetBSD: fdtvar.h,v 1.10 2017/04/21 23:35:01 jmcneill Exp $ */
 
 /*-
  * Copyright (c) 2015 Jared D. McNeill <jmcneill%invisible.ca@localhost>
@@ -165,4 +165,8 @@
 int            fdtbus_offset2phandle(int);
 bool           fdtbus_get_path(int, char *, size_t);
 
+const char *   fdtbus_get_stdout_path(void);
+int            fdtbus_get_stdout_phandle(void);
+int            fdtbus_get_stdout_speed(void);
+
 #endif /* _DEV_FDT_FDTVAR_H */