Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg...

[~andy/linux] / arch / powerpc / kernel / machine_kexec.c

diff --git a/arch/powerpc/kernel/machine_kexec.c b/arch/powerpc/kernel/machine_kexec.c
index ac2a21f45c757a41f8ab639abca5a449d6576207..d59e2b1bdcbac7f1f64cf9d7289092345323f315 100644 (file)
--- a/arch/powerpc/kernel/machine_kexec.c
+++ b/arch/powerpc/kernel/machine_kexec.c
@@ -13,13 +13,17 @@
 #include <linux/reboot.h>
 #include <linux/threads.h>
 #include <linux/lmb.h>
+#include <linux/of.h>
 #include <asm/machdep.h>
 #include <asm/prom.h>
+#include <asm/sections.h>
 
 void machine_crash_shutdown(struct pt_regs *regs)
 {
        if (ppc_md.machine_crash_shutdown)
                ppc_md.machine_crash_shutdown(regs);
+       else
+               default_machine_crash_shutdown(regs);
 }
 
 /*
@@ -31,11 +35,8 @@ int machine_kexec_prepare(struct kimage *image)
 {
        if (ppc_md.machine_kexec_prepare)
                return ppc_md.machine_kexec_prepare(image);
-       /*
-        * Fail if platform doesn't provide its own machine_kexec_prepare
-        * implementation.
-        */
-       return -ENOSYS;
+       else
+               return default_machine_kexec_prepare(image);
 }
 
 void machine_kexec_cleanup(struct kimage *image)
@@ -52,13 +53,11 @@ void machine_kexec(struct kimage *image)
 {
        if (ppc_md.machine_kexec)
                ppc_md.machine_kexec(image);
-       else {
-               /*
-                * Fall back to normal restart if platform doesn't provide
-                * its own kexec function, and user insist to kexec...
-                */
-               machine_restart(NULL);
-       }
+       else
+               default_machine_kexec(image);
+
+       /* Fall back to normal restart if we're still alive. */
+       machine_restart(NULL);
        for(;;);
 }
 
@@ -94,10 +93,35 @@ void __init reserve_crashkernel(void)
                                KDUMP_KERNELBASE);
 
        crashk_res.start = KDUMP_KERNELBASE;
+#else
+       if (!crashk_res.start) {
+               /*
+                * unspecified address, choose a region of specified size
+                * can overlap with initrd (ignoring corruption when retained)
+                * ppc64 requires kernel and some stacks to be in first segemnt
+                */
+               crashk_res.start = KDUMP_KERNELBASE;
+       }
+
+       crash_base = PAGE_ALIGN(crashk_res.start);
+       if (crash_base != crashk_res.start) {
+               printk("Crash kernel base must be aligned to 0x%lx\n",
+                               PAGE_SIZE);
+               crashk_res.start = crash_base;
+       }
+
 #endif
        crash_size = PAGE_ALIGN(crash_size);
        crashk_res.end = crashk_res.start + crash_size - 1;
 
+       /* The crash region must not overlap the current kernel */
+       if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
+               printk(KERN_WARNING
+                       "Crash kernel can not overlap current kernel\n");
+               crashk_res.start = crashk_res.end = 0;
+               return;
+       }
+
        /* Crash kernel trumps memory limit */
        if (memory_limit && memory_limit <= crashk_res.end) {
                memory_limit = crashk_res.end + 1;
@@ -118,3 +142,71 @@ int overlaps_crashkernel(unsigned long start, unsigned long size)
 {
        return (start + size) > crashk_res.start && start <= crashk_res.end;
 }
+
+/* Values we need to export to the second kernel via the device tree. */
+static unsigned long kernel_end;
+static unsigned long crashk_size;
+
+static struct property kernel_end_prop = {
+       .name = "linux,kernel-end",
+       .length = sizeof(unsigned long),
+       .value = &kernel_end,
+};
+
+static struct property crashk_base_prop = {
+       .name = "linux,crashkernel-base",
+       .length = sizeof(unsigned long),
+       .value = &crashk_res.start,
+};
+
+static struct property crashk_size_prop = {
+       .name = "linux,crashkernel-size",
+       .length = sizeof(unsigned long),
+       .value = &crashk_size,
+};
+
+static void __init export_crashk_values(struct device_node *node)
+{
+       struct property *prop;
+
+       /* There might be existing crash kernel properties, but we can't
+        * be sure what's in them, so remove them. */
+       prop = of_find_property(node, "linux,crashkernel-base", NULL);
+       if (prop)
+               prom_remove_property(node, prop);
+
+       prop = of_find_property(node, "linux,crashkernel-size", NULL);
+       if (prop)
+               prom_remove_property(node, prop);
+
+       if (crashk_res.start != 0) {
+               prom_add_property(node, &crashk_base_prop);
+               crashk_size = crashk_res.end - crashk_res.start + 1;
+               prom_add_property(node, &crashk_size_prop);
+       }
+}
+
+static int __init kexec_setup(void)
+{
+       struct device_node *node;
+       struct property *prop;
+
+       node = of_find_node_by_path("/chosen");
+       if (!node)
+               return -ENOENT;
+
+       /* remove any stale properties so ours can be found */
+       prop = of_find_property(node, kernel_end_prop.name, NULL);
+       if (prop)
+               prom_remove_property(node, prop);
+
+       /* information needed by userspace when using default_machine_kexec */
+       kernel_end = __pa(_end);
+       prom_add_property(node, &kernel_end_prop);
+
+       export_crashk_values(node);
+
+       of_node_put(node);
+       return 0;
+}
+late_initcall(kexec_setup);