[PATCH rebased] powerpc/fadump: when fadump is supported register the fadump sysfs files.

[Michal Suchanek <msuchanek@suse.de>]

Currently it is not possible to distinguish the case when fadump is
supported by firmware and disabled in kernel and completely unsupported
using the kernel sysfs interface. User can investigate the devicetree
but it is more reasonable to provide sysfs files in case we get some
fadumpv2 in the future.

With this patch sysfs files are available whenever fadump is supported
by firmware.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
Rebase on top of http://patchwork.ozlabs.org/patch/1150160/
[v5,31/31] powernv/fadump: support holes in kernel boot memory area
---
 arch/powerpc/kernel/fadump.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 4b1bb3c55cf9..7ad424729e9c 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1319,13 +1319,9 @@ static void fadump_init_files(void)
  */
 int __init setup_fadump(void)
 {
-	if (!fw_dump.fadump_enabled)
-		return 0;
-
-	if (!fw_dump.fadump_supported) {
+	if (!fw_dump.fadump_supported && fw_dump.fadump_enabled) {
 		printk(KERN_ERR "Firmware-assisted dump is not supported on"
 			" this hardware\n");
-		return 0;
 	}
 
 	fadump_show_config();
@@ -1333,19 +1329,26 @@ int __init setup_fadump(void)
 	 * If dump data is available then see if it is valid and prepare for
 	 * saving it to the disk.
 	 */
-	if (fw_dump.dump_active) {
+	if (fw_dump.fadump_enabled) {
+		if (fw_dump.dump_active) {
+			/*
+			 * if dump process fails then invalidate the
+			 * registration and release memory before proceeding
+			 * for re-registration.
+			 */
+			if (fw_dump.ops->fadump_process(&fw_dump) < 0)
+				fadump_invalidate_release_mem();
+		}
 		/*
-		 * if dump process fails then invalidate the registration
-		 * and release memory before proceeding for re-registration.
+		 * Initialize the kernel dump memory structure for FAD
+		 * registration.
 		 */
-		if (fw_dump.ops->fadump_process(&fw_dump) < 0)
-			fadump_invalidate_release_mem();
-	}
-	/* Initialize the kernel dump memory structure for FAD registration. */
-	else if (fw_dump.reserve_dump_area_size)
-		fw_dump.ops->fadump_init_mem_struct(&fw_dump);
+		else if (fw_dump.reserve_dump_area_size)
+			fw_dump.ops->fadump_init_mem_struct(&fw_dump);
 
-	fadump_init_files();
+	}
+	if (fw_dump.fadump_supported)
+		fadump_init_files();
 
 	return 1;
 }
-- 
2.22.0