[Crash-utility] [PATCH] Fix display processor speed on ppc/ppc64

[Pavan Naregundi]

Hi Everyone,

On Power6 crash displays "MACHINE: ppc64 (unknown Mhz)" for processor
speed upon initialization and by the "sys" sub-command.

# crash

crash 5.0.1
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This GDB was configured as "powerpc64-unknown-linux-gnu"...

      KERNEL: /boot/vmlinux-2.6.32.9-0.5-ppc64
    DUMPFILE: /dev/mem
        CPUS: 5
        DATE: Thu Mar 18 03:13:59 2010
      UPTIME: 04:11:31
LOAD AVERAGE: 0.34, 0.15, 0.05
       TASKS: 319
    NODENAME: brucelp3
     RELEASE: 2.6.32.9-0.5-ppc64
     VERSION: #1 SMP 2010-03-15 12:22:00 +0100
     MACHINE: ppc64  (unknown Mhz) ======> display unknown Mhz
      MEMORY: 1 GB
         PID: 17788
     COMMAND: "crash"
        TASK: c00000003ae58b80  [THREAD_INFO: c00000003df68000]
         CPU: 6
       STATE: TASK_RUNNING (ACTIVE)
=====================

When investigated this issue was absence of 'have_of' symbol in current
kernels. Below is the commit which removed the support of 'have_of'.

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=6b82b3e4b54b2fce2ca11976c535012b836b2016


This patch overcomes the use of 'have_of' variable.. Please review this
patch..

Regards,
Pavan
IBM Linux Technology Center

---
diff -Naur a/ppc64.c b/ppc64.c
--- a/ppc64.c	2010-03-24 10:14:33.000000000 +0530
+++ b/ppc64.c	2010-03-24 10:14:51.000000000 +0530
@@ -742,7 +742,7 @@
 ppc64_processor_speed(void)
 {
         ulong res, value, ppc_md, md_setup_res;
-        ulong we_have_of, prep_setup_res;
+        ulong prep_setup_res;
         ulong node, type, name, properties;
 	char str_buf[32];
 	uint len;
@@ -751,22 +751,12 @@
         if (machdep->mhz)
                 return(machdep->mhz);
 
-        /* first, check if the have_of variable a) exists, and b) is
TRUE */
-        if(symbol_exists("have_of")) {
-                get_symbol_data("have_of", sizeof(void *),
&we_have_of);
-        } else {
-                we_have_of = 0;
-        }
-
-        if(we_have_of) {
+        if(symbol_exists("allnodes")) {
                 /* we have a machine with open firmware, so search the
OF nodes
                  * for cpu nodes.
                  * Too bad we can't call kernel helper functions
here :)
                  */
 
-                if(!symbol_exists("allnodes"))
-                        return (machdep->mhz = 0);
-
                 get_symbol_data("allnodes", sizeof(void *), &node);
                 while(node) {
                         readmem(node+OFFSET(device_node_type),
diff -Naur a/ppc.c b/ppc.c
--- a/ppc.c	2010-03-24 10:14:33.000000000 +0530
+++ b/ppc.c	2010-03-24 10:14:51.000000000 +0530
@@ -461,7 +461,7 @@
 ppc_processor_speed(void)
 {
 	ulong res, value, ppc_md, md_setup_res;
-	ulong we_have_of, prep_setup_res;
+	ulong prep_setup_res;
 	ulong node, type, name, properties;
 	char str_buf[16];
 	ulong len, mhz = 0;
@@ -469,22 +469,12 @@
 	if (machdep->mhz)
 		return(machdep->mhz);
 
-	/* first, check if the have_of variable a) exists, and b) is TRUE */
-	if(symbol_exists("have_of")) {
-		get_symbol_data("have_of", sizeof(void *), &we_have_of);
-	} else {
-		we_have_of = 0;
-	}
-
-	if(we_have_of) {
+	if(symbol_exists("allnodes")) {
 		/* we have a machine with open firmware, so search the OF nodes 
 		 * for cpu nodes.
 		 * Too bad we can't call kernel helper functions here :)
 		 */
 		
-		if(!symbol_exists("allnodes"))
-			return (machdep->mhz = 0);
-		
 		get_symbol_data("allnodes", sizeof(void *), &node);
 		while(node) {
 			readmem(node+OFFSET(device_node_type),