cpc925_edac: Support single-processor configurations
If second CPU is not enabled, CPC925 EDAC driver will spill out warnings
about errors on second Processor Interface. Support masking that out,
by detecting at runtime which CPUs are present in device tree.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Harry Ciao <qingtao.cao@windriver.com>
Cc: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/drivers/edac/cpc925_edac.c b/drivers/edac/cpc925_edac.c
index a687a0d..a774c0d 100644
--- a/drivers/edac/cpc925_edac.c
+++ b/drivers/edac/cpc925_edac.c
@@ -90,6 +90,7 @@
ECC_MASK_ENABLE = (APIMASK_ECC_UE_H | APIMASK_ECC_CE_H |
APIMASK_ECC_UE_L | APIMASK_ECC_CE_L),
};
+#define APIMASK_ADI(n) CPC925_BIT(((n)+1))
/************************************************************
* Processor Interface Exception Register (APIEXCP)
@@ -581,16 +582,73 @@
}
/******************** CPU err device********************************/
+static u32 cpc925_cpu_mask_disabled(void)
+{
+ struct device_node *cpus;
+ struct device_node *cpunode = NULL;
+ static u32 mask = 0;
+
+ /* use cached value if available */
+ if (mask != 0)
+ return mask;
+
+ mask = APIMASK_ADI0 | APIMASK_ADI1;
+
+ cpus = of_find_node_by_path("/cpus");
+ if (cpus == NULL) {
+ cpc925_printk(KERN_DEBUG, "No /cpus node !\n");
+ return 0;
+ }
+
+ while ((cpunode = of_get_next_child(cpus, cpunode)) != NULL) {
+ const u32 *reg = of_get_property(cpunode, "reg", NULL);
+
+ if (strcmp(cpunode->type, "cpu")) {
+ cpc925_printk(KERN_ERR, "Not a cpu node in /cpus: %s\n", cpunode->name);
+ continue;
+ }
+
+ if (reg == NULL || *reg > 2) {
+ cpc925_printk(KERN_ERR, "Bad reg value at %s\n", cpunode->full_name);
+ continue;
+ }
+
+ mask &= ~APIMASK_ADI(*reg);
+ }
+
+ if (mask != (APIMASK_ADI0 | APIMASK_ADI1)) {
+ /* We assume that each CPU sits on it's own PI and that
+ * for present CPUs the reg property equals to the PI
+ * interface id */
+ cpc925_printk(KERN_WARNING,
+ "Assuming PI id is equal to CPU MPIC id!\n");
+ }
+
+ of_node_put(cpunode);
+ of_node_put(cpus);
+
+ return mask;
+}
+
/* Enable CPU Errors detection */
static void cpc925_cpu_init(struct cpc925_dev_info *dev_info)
{
u32 apimask;
+ u32 cpumask;
apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
- if ((apimask & CPU_MASK_ENABLE) == 0) {
- apimask |= CPU_MASK_ENABLE;
- __raw_writel(apimask, dev_info->vbase + REG_APIMASK_OFFSET);
+
+ cpumask = cpc925_cpu_mask_disabled();
+ if (apimask & cpumask) {
+ cpc925_printk(KERN_WARNING, "CPU(s) not present, "
+ "but enabled in APIMASK, disabling\n");
+ apimask &= ~cpumask;
}
+
+ if ((apimask & CPU_MASK_ENABLE) == 0)
+ apimask |= CPU_MASK_ENABLE;
+
+ __raw_writel(apimask, dev_info->vbase + REG_APIMASK_OFFSET);
}
/* Disable CPU Errors detection */
@@ -622,6 +680,9 @@
if ((apiexcp & CPU_EXCP_DETECTED) == 0)
return;
+ if ((apiexcp & ~cpc925_cpu_mask_disabled()) == 0)
+ return;
+
apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
cpc925_printk(KERN_INFO, "Processor Interface Fault\n"
"Processor Interface register dump:\n");