android_kernel_xiaomi_sm8350/arch/sparc64/prom/tree.c
David S. Miller c73fcc846c [SPARC]: Fix serial console device detection.
The current scheme works on static interpretation of text names, which
is wrong.

The output-device setting, for example, must be resolved via an alias
or similar to a full path name to the console device.

Paths also contain an optional set of 'options', which starts with a
colon at the end of the path.  The option area is used to specify
which of two serial ports ('a' or 'b') the path refers to when a
device node drives multiple ports.  'a' is assumed if the option
specification is missing.

This was caught by the UltraSPARC-T1 simulator.  The 'output-device'
property was set to 'ttya' and we didn't pick upon the fact that this
is an OBP alias set to '/virtual-devices/console'.  Instead we saw it
as the first serial console device, instead of the hypervisor console.

The infrastructure is now there to take advantage of this to resolve
the console correctly even in multi-head situations in fbcon too.

Thanks to Greg Onufer for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-20 16:59:26 -07:00

315 lines
6.6 KiB
C

/* $Id: tree.c,v 1.10 1998/01/10 22:39:00 ecd Exp $
* tree.c: Basic device tree traversal/scanning for the Linux
* prom library.
*
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <linux/string.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/ldc.h>
/* Return the child of node 'node' or zero if no this node has no
* direct descendent.
*/
__inline__ int
__prom_getchild(int node)
{
return p1275_cmd ("child", P1275_INOUT(1, 1), node);
}
__inline__ int
prom_getchild(int node)
{
int cnode;
if(node == -1) return 0;
cnode = __prom_getchild(node);
if(cnode == -1) return 0;
return (int)cnode;
}
__inline__ int
prom_getparent(int node)
{
int cnode;
if(node == -1) return 0;
cnode = p1275_cmd ("parent", P1275_INOUT(1, 1), node);
if(cnode == -1) return 0;
return (int)cnode;
}
/* Return the next sibling of node 'node' or zero if no more siblings
* at this level of depth in the tree.
*/
__inline__ int
__prom_getsibling(int node)
{
return p1275_cmd(prom_peer_name, P1275_INOUT(1, 1), node);
}
__inline__ int
prom_getsibling(int node)
{
int sibnode;
if (node == -1)
return 0;
sibnode = __prom_getsibling(node);
if (sibnode == -1)
return 0;
return sibnode;
}
/* Return the length in bytes of property 'prop' at node 'node'.
* Return -1 on error.
*/
__inline__ int
prom_getproplen(int node, const char *prop)
{
if((!node) || (!prop)) return -1;
return p1275_cmd ("getproplen",
P1275_ARG(1,P1275_ARG_IN_STRING)|
P1275_INOUT(2, 1),
node, prop);
}
/* Acquire a property 'prop' at node 'node' and place it in
* 'buffer' which has a size of 'bufsize'. If the acquisition
* was successful the length will be returned, else -1 is returned.
*/
__inline__ int
prom_getproperty(int node, const char *prop, char *buffer, int bufsize)
{
int plen;
plen = prom_getproplen(node, prop);
if ((plen > bufsize) || (plen == 0) || (plen == -1)) {
return -1;
} else {
/* Ok, things seem all right. */
return p1275_cmd(prom_getprop_name,
P1275_ARG(1,P1275_ARG_IN_STRING)|
P1275_ARG(2,P1275_ARG_OUT_BUF)|
P1275_INOUT(4, 1),
node, prop, buffer, P1275_SIZE(plen));
}
}
/* Acquire an integer property and return its value. Returns -1
* on failure.
*/
__inline__ int
prom_getint(int node, const char *prop)
{
int intprop;
if(prom_getproperty(node, prop, (char *) &intprop, sizeof(int)) != -1)
return intprop;
return -1;
}
/* Acquire an integer property, upon error return the passed default
* integer.
*/
int
prom_getintdefault(int node, const char *property, int deflt)
{
int retval;
retval = prom_getint(node, property);
if(retval == -1) return deflt;
return retval;
}
/* Acquire a boolean property, 1=TRUE 0=FALSE. */
int
prom_getbool(int node, const char *prop)
{
int retval;
retval = prom_getproplen(node, prop);
if(retval == -1) return 0;
return 1;
}
/* Acquire a property whose value is a string, returns a null
* string on error. The char pointer is the user supplied string
* buffer.
*/
void
prom_getstring(int node, const char *prop, char *user_buf, int ubuf_size)
{
int len;
len = prom_getproperty(node, prop, user_buf, ubuf_size);
if(len != -1) return;
user_buf[0] = 0;
return;
}
/* Does the device at node 'node' have name 'name'?
* YES = 1 NO = 0
*/
int
prom_nodematch(int node, const char *name)
{
char namebuf[128];
prom_getproperty(node, "name", namebuf, sizeof(namebuf));
if(strcmp(namebuf, name) == 0) return 1;
return 0;
}
/* Search siblings at 'node_start' for a node with name
* 'nodename'. Return node if successful, zero if not.
*/
int
prom_searchsiblings(int node_start, const char *nodename)
{
int thisnode, error;
char promlib_buf[128];
for(thisnode = node_start; thisnode;
thisnode=prom_getsibling(thisnode)) {
error = prom_getproperty(thisnode, "name", promlib_buf,
sizeof(promlib_buf));
/* Should this ever happen? */
if(error == -1) continue;
if(strcmp(nodename, promlib_buf)==0) return thisnode;
}
return 0;
}
/* Return the first property type for node 'node'.
* buffer should be at least 32B in length
*/
__inline__ char *
prom_firstprop(int node, char *buffer)
{
*buffer = 0;
if(node == -1) return buffer;
p1275_cmd ("nextprop", P1275_ARG(2,P1275_ARG_OUT_32B)|
P1275_INOUT(3, 0),
node, (char *) 0x0, buffer);
return buffer;
}
/* Return the property type string after property type 'oprop'
* at node 'node' . Returns NULL string if no more
* property types for this node.
*/
__inline__ char *
prom_nextprop(int node, const char *oprop, char *buffer)
{
char buf[32];
if(node == -1) {
*buffer = 0;
return buffer;
}
if (oprop == buffer) {
strcpy (buf, oprop);
oprop = buf;
}
p1275_cmd ("nextprop", P1275_ARG(1,P1275_ARG_IN_STRING)|
P1275_ARG(2,P1275_ARG_OUT_32B)|
P1275_INOUT(3, 0),
node, oprop, buffer);
return buffer;
}
int
prom_finddevice(const char *name)
{
if (!name)
return 0;
return p1275_cmd(prom_finddev_name,
P1275_ARG(0,P1275_ARG_IN_STRING)|
P1275_INOUT(1, 1),
name);
}
int prom_node_has_property(int node, const char *prop)
{
char buf [32];
*buf = 0;
do {
prom_nextprop(node, buf, buf);
if(!strcmp(buf, prop))
return 1;
} while (*buf);
return 0;
}
/* Set property 'pname' at node 'node' to value 'value' which has a length
* of 'size' bytes. Return the number of bytes the prom accepted.
*/
int
prom_setprop(int node, const char *pname, char *value, int size)
{
if (size == 0)
return 0;
if ((pname == 0) || (value == 0))
return 0;
#ifdef CONFIG_SUN_LDOMS
if (ldom_domaining_enabled) {
ldom_set_var(pname, value);
return 0;
}
#endif
return p1275_cmd ("setprop", P1275_ARG(1,P1275_ARG_IN_STRING)|
P1275_ARG(2,P1275_ARG_IN_BUF)|
P1275_INOUT(4, 1),
node, pname, value, P1275_SIZE(size));
}
__inline__ int
prom_inst2pkg(int inst)
{
int node;
node = p1275_cmd ("instance-to-package", P1275_INOUT(1, 1), inst);
if (node == -1) return 0;
return node;
}
/* Return 'node' assigned to a particular prom 'path'
* FIXME: Should work for v0 as well
*/
int
prom_pathtoinode(const char *path)
{
int node, inst;
inst = prom_devopen (path);
if (inst == 0) return 0;
node = prom_inst2pkg (inst);
prom_devclose (inst);
if (node == -1) return 0;
return node;
}
int prom_ihandle2path(int handle, char *buffer, int bufsize)
{
return p1275_cmd("instance-to-path",
P1275_ARG(1,P1275_ARG_OUT_BUF)|
P1275_INOUT(3, 1),
handle, buffer, P1275_SIZE(bufsize));
}