In the current version of dtc, if one has the line:

/config/ = "northbridge/amd/geodelx";

Then the file northbridge/amd/geodelx/dts is read in and processed. 
Magic(TM) appends the name "/dts" to the path. 

This hack is fine with chips that only do one thing. 
But some (all) northbridge parts play several roles: APIC cluster, PCI domain
device, and PCI device. The result is a need for more than one dts, since
there are three possible devices, with three types of IDs, and so on. 

To keep things sane, I am proposing to enable multiple dts files in a
directory, names (e.g., nothing required here):
domaindts
pcidts
apicdts

(of course these names can be anything, this is just an example).
This change will require a change to the dtc, since we can no longer
assume just one dts file, and hence need a way to name these different 
files. 

The proposed change is very simple. We now require the full path name 
for the file, and eliminate the Magic(TM).

So, 
/config/ = "northbridge/amd/geodelx/pcidts";

will open the pcidts file. 
/config/ = "northbridge/amd/geodelx/domaindts";
will open the domain dts. 

Maybe we should just call it domain and pci and apic? works for me.
/config/ = "northbridge/amd/geodelx/domain";
/config/ = "northbridge/amd/geodelx/pcibridge";
/config/ = "northbridge/amd/geodelx/apic";

Changes: 
dtc.c: create a new function, fopenfile, that will only open a path if it 
really is a file. Modify dtc_open_file to use this function. fopenfile
assumes "-" means stdin; should it, or should I move that assumption back
to dtc_open_file?
dtc.h: add prototypes
dtc-parser.y: Given a config path, open the path.
southbridge/amd/cs5536/cs5536.c: example of how C code changes


Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>

Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>

Please see the comments below, but they do not have to be addressed for
this commit, just keep them in mind for future commits in that area.



git-svn-id: svn://coreboot.org/repository/coreboot-v3@566 f3766cd6-281f-0410-b1cd-43a5c92072e9

southbridge/amd/cs5536/cs5536.c

@@ -172,7 +172,7 @@ static void enable_ide_nand_flash_header(void)
  *
  * @param sb Southbridge config structure.
  */
-static void lpc_init(struct southbridge_amd_cs5536_config *sb)
+static void lpc_init(struct southbridge_amd_cs5536_dts_config *sb)
 {
 	struct msr msr;
 
@@ -220,7 +220,7 @@ static void lpc_init(struct southbridge_amd_cs5536_config *sb)
  *
  * @param sb Southbridge config structure.
  */
-static void uarts_init(struct southbridge_amd_cs5536_config *sb)
+static void uarts_init(struct southbridge_amd_cs5536_dts_config *sb)
 {
 	struct msr msr;
 	u16 addr = 0;
@@ -383,7 +383,7 @@ static void uarts_init(struct southbridge_amd_cs5536_config *sb)
  *
  * @param sb Southbridge config structure.
  */
-static void enable_USB_port4(struct southbridge_amd_cs5536_config *sb)
+static void enable_USB_port4(struct southbridge_amd_cs5536_dts_config *sb)
 {
 	u32 *bar;
 	struct msr msr;
@@ -475,7 +475,7 @@ void chipsetinit(void)
 {
 	struct device *dev;
 	struct msr msr;
-	struct southbridge_amd_cs5536_config *sb;
+	struct southbridge_amd_cs5536_dts_config *sb;
 	const struct msrinit *csi;
 
 	post_code(P80_CHIPSET_INIT);
@@ -486,7 +486,7 @@ void chipsetinit(void)
 		       __FUNCTION__);
 		return;
 	}
-	sb = (struct southbridge_amd_cs5536_config *)dev->device_configuration;
+	sb = (struct southbridge_amd_cs5536_dts_config *)dev->device_configuration;
 
 #if 0
 	if (!IsS3Resume())
@@ -548,8 +548,8 @@ void chipsetinit(void)
  */
 static void southbridge_init(struct device *dev)
 {
-	struct southbridge_amd_cs5536_config *sb =
-	    (struct southbridge_amd_cs5536_config *)dev->device_configuration;
+	struct southbridge_amd_cs5536_dts_config *sb =
+	    (struct southbridge_amd_cs5536_dts_config *)dev->device_configuration;
 
 	/*
 	 * struct device *gpiodev;

util/dtc/dtc-parser.y

@@ -121,17 +121,16 @@ proplist:	propdef proplist {
 config:        DT_CONFIG '(' 
 		includepath {
 			void switchin(FILE *f);
-
-			/* switch ... */
-			char path[1024];
 			FILE *f;
+			/* The need for a cast here is silly */
+			char *name = (char *)$3.val;
+
 			/* TODO: keep track of which of these we have read in. If we have already done it, then 
 			  * don't do it twice. 
 			  */
-			sprintf(path, "%s/dts", $3.val);
-			f  = fopen(path, "r");
+			f  = fopenfile(name);
 			if (! f){
-				perror(path);
+				perror(name);
 				exit(1);
 			}
 			switchin(f);

util/dtc/dtc.c

@@ -61,14 +61,39 @@ void fill_fullpaths(struct node *tree, char *prefix)
 		fill_fullpaths(child, tree->fullpath);
 }
 
-static FILE *dtc_open_file(char *fname)
+/* How stupid is POSIX? This stupid: you can fopen a directory if mode
+ * is "r", but then there is very little you can do with it except get errors. 
+ * This function now makes sure that the thing you open is a file. 
+ */
+FILE *fopenfile(char *fname)
 {
-	FILE *f;
+	FILE *f = NULL;
 
-	if (streq(fname, "-"))
+	if (streq(fname, "-")){
 		f = stdin;
-	else
+	} else {
+		struct stat buf;
+		if (stat(fname, &buf) < 0) {
+			errno = EISDIR;
+			goto no;
+		}
+
+		if (! S_ISREG(buf.st_mode)){
+			errno = EISDIR;
+			goto no;
+		}
+
 		f = fopen(fname, "r");
+	}
+
+no:
+
+	return f;
+}
+
+FILE *dtc_open_file(char *fname)
+{
+	FILE *f = fopenfile(fname);
 
 	if (! f)
 		die("Couldn't open \"%s\": %s\n", fname, strerror(errno));
@@ -76,6 +101,7 @@ static FILE *dtc_open_file(char *fname)
 	return f;
 }
 
+
 static void usage(void)
 {
 	fprintf(stderr, "Usage:\n");

util/dtc/dtc.h

@@ -31,6 +31,8 @@
 #include <errno.h>
 #include <unistd.h>
 #include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 
 /* also covers (part of?) linux's byteswap.h functionality */
 #include "endian.h"
@@ -236,5 +238,6 @@ struct boot_info *dt_from_fs(char *dirname);
 
 char *join_path(char *path, char *name);
 void fill_fullpaths(struct node *tree, char *prefix);
-
+FILE *fopenfile(char *fname);
+FILE *dtc_open_file(char *fname);
 #endif /* _DTC_H */