[U-Boot] [PATCH v2 31/51] x86: Add support for running Intel reference code

[Simon Glass]

Intel has invented yet another binary blob which firmware is required to
run. This is run after SDRAM is ready. It is linked to load at a particular
address, typically 0, but is a relocatable ELF so can be moved if required.

Add support for this in the build system. The file should be placed in the
board directory, and called refcode.elf.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v2:
- Fix 'PCB' typo (should be 'PCH')

 Makefile                   | 14 +++++++++++++-
 arch/x86/Kconfig           | 11 +++++++++++
 arch/x86/include/asm/cpu.h | 12 ++++++++++++
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index fadf1a3..3fbaea4 100644
--- a/Makefile
+++ b/Makefile
@@ -1044,6 +1044,10 @@ ifneq ($(CONFIG_HAVE_VGA_BIOS),)
 IFDTOOL_FLAGS += -w $(CONFIG_VGA_BIOS_ADDR):$(srctree)/board/$(BOARDDIR)/$(CONFIG_VGA_BIOS_FILE)
 endif
 
+ifneq ($(CONFIG_HAVE_REFCODE),)
+IFDTOOL_FLAGS += -w $(CONFIG_X86_REFCODE_ADDR):refcode.bin
+endif
+
 quiet_cmd_ifdtool = IFDTOOL $@
 cmd_ifdtool  = $(IFDTOOL) -c -r $(CONFIG_ROM_SIZE) u-boot.tmp;
 ifneq ($(CONFIG_HAVE_INTEL_ME),)
@@ -1052,7 +1056,15 @@ endif
 cmd_ifdtool += $(IFDTOOL) $(IFDTOOL_FLAGS) u-boot.tmp;
 cmd_ifdtool += mv u-boot.tmp $@
 
-u-boot.rom: u-boot-x86-16bit.bin u-boot.bin FORCE
+refcode.bin: $(srctree)/board/$(BOARDDIR)/refcode.bin FORCE
+	$(call if_changed,copy)
+
+quiet_cmd_ldr = LD      $@
+cmd_ldr = $(LD) $(LDFLAGS_$(@F)) \
+	       $(filter-out FORCE,$^) -o $@
+
+u-boot.rom: u-boot-x86-16bit.bin u-boot.bin FORCE \
+		$(if $(CONFIG_HAVE_REFCODE),refcode.bin)
 	$(call if_changed,ifdtool)
 
 OBJCOPYFLAGS_u-boot-x86-16bit.bin := -O binary -j .start16 -j .resetvec
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 64c824f..1a9fa40 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -327,6 +327,17 @@ config DCACHE_RAM_MRC_VAR_SIZE
 	  memory reference code and must be set correctly or the board will
 	  not boot.
 
+config HAVE_REFCODE
+        bool "Add a Reference Code binary"
+        help
+          Select this option to add a Reference Code binary to the resulting
+          U-Boot image. This is an Intel binary blob that handles system
+          initialisation, in this case the PCH and System Agent.
+
+          Note: Without this binary (on platforms that need it such as
+          broadwell) U-Boot will be missing some critical setup steps.
+          Various peripherals may fail to work.
+
 config SMP
 	bool "Enable Symmetric Multiprocessing"
 	default n
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index 85386da..7892757 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -275,4 +275,16 @@ u32 cpu_get_family_model(void);
  */
 u32 cpu_get_stepping(void);
 
+/**
+ * cpu_run_reference_code() - Run the platform reference code
+ *
+ * Some platforms require a binary blob to be executed once SDRAM is
+ * available. This is used to set up various platform features, such as the
+ * platform controller hub (PCH). This function should be implemented by the
+ * CPU-specific code.
+ *
+ * @return 0 on success, -ve on failure
+ */
+int cpu_run_reference_code(void);
+
 #endif
-- 
2.7.0.rc3.207.g0ac5344