[Cbe-oss-dev] [PATCH] fix cbe_thermal for legacy SLOF tree.

[Jean-Christophe Dubois]

On some legacy SLOF tree the generic code is unable to ioremap some Cell BE 
registers. Therefore the "generic" functions are returning a NULL pointer, 
triggering a crash on such platforms.

Let's handle this more gracefully.

Signed-off-by: Jean-Christophe DUBOIS <jcd at tribudubois.net>

Index: linux-2.6.22-rc4/arch/powerpc/platforms/cell/cbe_thermal.c
===================================================================
--- linux-2.6.22-rc4.orig/arch/powerpc/platforms/cell/cbe_thermal.c
+++ linux-2.6.22-rc4/arch/powerpc/platforms/cell/cbe_thermal.c
@@ -108,6 +108,11 @@ static ssize_t spu_show_temp(struct sys_
 
 	pmd_regs = get_pmd_regs(sysdev);
 
+	if (!pmd_regs) {
+		WARN_ON_ONCE(!pmd_regs);
+		return 0;
+	}
+
 	value = spu_read_register_value(sysdev, &pmd_regs->ts_ctsr1);
 
 	return sprintf(buf, "%d\n", reg_to_temp(value));
@@ -117,6 +122,11 @@ static ssize_t show_throttle(struct cbe_
 {
 	u64 value;
 
+	if (!pmd_regs) {
+		WARN_ON_ONCE(!pmd_regs);
+		return 0;
+	}
+
 	value = in_be64(&pmd_regs->tm_tpr.val);
 	/* access the corresponding byte */
 	value >>= pos;
@@ -186,6 +196,12 @@ static ssize_t ppe_show_temp(struct sys_
 	u64 value;
 
 	pmd_regs = cbe_get_cpu_pmd_regs(sysdev->id);
+
+	if (!pmd_regs) {
+		WARN_ON_ONCE(!pmd_regs);
+		return 0;
+	}
+
 	value = in_be64(&pmd_regs->ts_ctsr2);
 
 	value = (value >> pos) & 0x3f;
@@ -339,8 +355,19 @@ static void __init init_default_values(v
 	for_each_possible_cpu (cpu) {
 		pr_debug("processing cpu %d\n", cpu);
 		sysdev = get_cpu_sysdev(cpu);
+
+		if (!sysdev) {
+			WARN_ON_ONCE(!sysdev);
+			continue;
+		}
+
 		pmd_regs = cbe_get_cpu_pmd_regs(sysdev->id);
 
+		if (!pmd_regs) {
+			WARN_ON_ONCE(!pmd_regs);
+			continue;
+		}
+
 		out_be64(&pmd_regs->tm_str2, str2);
 		out_be64(&pmd_regs->tm_str1.val, str1.val);
 		out_be64(&pmd_regs->tm_tpr.val, tpr.val);