powerpc/maple: Register CPC925 EDAC device on all boards with CPC925

Currently Maple setup code creates cpc925_edac device only on
Motorola ATCA-6101 blade. Make setup code check bridge revision
and enable EDAC on all U3H bridges.

Verified on Momentum MapleD (ppc970fx kit) board.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 19 insertions, 22 deletions

diff --git a/arch/powerpc/platforms/maple/setup.c b/arch/powerpc/platforms/maple/setup.c
index fe34c3d9bb74..5b3388b9f911 100644
--- a/arch/powerpc/platforms/maple/setup.c
+++ b/arch/powerpc/platforms/maple/setup.c
@@ -338,35 +338,16 @@ define_machine(maple) {
 #ifdef CONFIG_EDAC
 /*
  * Register a platform device for CPC925 memory controller on
- * Motorola ATCA-6101 blade.
+ * all boards with U3H (CPC925) bridge.
  */
-#define MAPLE_CPC925_MODEL      "Motorola,ATCA-6101"
 static int __init maple_cpc925_edac_setup(void)
 {
         struct platform_device *pdev;
         struct device_node *np = NULL;
         struct resource r;
-        const unsigned char *model;
         int ret;
-
-        np = of_find_node_by_path("/");
-        if (!np) {
-                printk(KERN_ERR "%s: Unable to get root node\n", __func__);
-                return -ENODEV;
-        }
-
-        model = (const unsigned char *)of_get_property(np, "model", NULL);
-        if (!model) {
-                printk(KERN_ERR "%s: Unabel to get model info\n", __func__);
-                of_node_put(np);
-                return -ENODEV;
-        }
-
-        ret = strcmp(model, MAPLE_CPC925_MODEL);
-        of_node_put(np);
-
-        if (ret != 0)
-                return 0;
+        volatile void __iomem *mem;
+        u32 rev;
 
         np = of_find_node_by_type(NULL, "memory-controller");
         if (!np) {
@@ -384,6 +365,22 @@ static int __init maple_cpc925_edac_setup(void)
                 return -ENODEV;
         }
 
+        mem = ioremap(r.start, resource_size(&r));
+        if (!mem) {
+                printk(KERN_ERR "%s: Unable to map memory-controller memory\n",
+                                __func__);
+                return -ENOMEM;
+        }
+
+        rev = __raw_readl(mem);
+        iounmap(mem);
+
+        if (rev < 0x34 || rev > 0x3f) { /* U3H */
+                printk(KERN_ERR "%s: Non-CPC925(U3H) bridge revision: %02x\n",
+                        __func__, rev);
+                return 0;
+        }
+
         pdev = platform_device_register_simple("cpc925_edac", 0, &r, 1);
         if (IS_ERR(pdev))
                 return PTR_ERR(pdev);