[coreboot-gerrit] Patch set updated for coreboot: cpu: create an empty file when no microcode files are given

[Alexander Couzens (lynxis@fe80.eu)]

Alexander Couzens (lynxis at fe80.eu) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/12109

-gerrit

commit 9dd465a7427aa9284509f68718f53e551efe780f
Author: Alexander Couzens <lynxis at fe80.eu>
Date:   Wed Oct 21 12:02:39 2015 +0200

    cpu: create an empty file when no microcode files are given
    
    Having an empty microcode file makes it more easy to debug
    in comparison to a not existing file in cbfs. There are some
    platforms (e.g. ep80579) which support microcode updates but
    not having any microcode updates yet in our tree.
    
    These platform hang the build because `cat` is called with no
    parameters.
    
    Change-Id: I2699bde0c62ae62ca888686f8b496e845c36d970
    Signed-off-by: Alexander Couzens <lynxis at fe80.eu>
---
 src/cpu/Makefile.inc                | 2 +-
 src/cpu/intel/microcode/microcode.c | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/cpu/Makefile.inc b/src/cpu/Makefile.inc
index d939061..52b58f7 100644
--- a/src/cpu/Makefile.inc
+++ b/src/cpu/Makefile.inc
@@ -40,7 +40,7 @@ endif
 $(obj)/cpu_microcode_blob.bin: $$(cpu_microcode_bins)
 	@printf "    MICROCODE  $(subst $(obj)/,,$(@))\n"
 	@echo $(cpu_microcode_bins)
-	cat $+ > $@
+	cat /dev/null $+ > $@
 
 cbfs-files-$(cbfs_include_ucode) += cpu_microcode_blob.bin
 cpu_microcode_blob.bin-file := $(cpu_ucode_cbfs_file)
diff --git a/src/cpu/intel/microcode/microcode.c b/src/cpu/intel/microcode/microcode.c
index 8791a2e..76d9e10 100644
--- a/src/cpu/intel/microcode/microcode.c
+++ b/src/cpu/intel/microcode/microcode.c
@@ -141,6 +141,8 @@ const void *intel_microcode_find(void)
 	if (ucode_updates == NULL)
 		return NULL;
 #endif
+	if (microcode_len == 0)
+		return NULL;
 
 	/* CPUID sets MSR 0x8B iff a microcode update has been loaded. */
 	msr.lo = 0;