fsp platfoms: add prototype & consolidate main entry-point

- In '-ffreestanding' main() is just as any other function and so
it needs a type-signature. Fixes a clang warning.

- Bay Trail and Rangeley have the updated romstage.c with the code
moved into the chipset, put the prototype in romstage.c.

- The sandybridge code has not been updated, so the prototype
for it goes into chipset_fsp_util.h, next to the prototype for
romstage_main_continue.

- Correct the return value of baytrail main() from void * to void
and remove the unnecessary asmlinkage tag. I'm surprised that this
didn't generate a warning...

Change-Id: I85ac0797d1e55d2b7ffdca039a52820d7827e704
Signed-off-by: Martin Roth <martin.roth@se-eng.com>
Reviewed-on: http://review.coreboot.org/7724
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>

src/mainboard/intel/cougar_canyon2/romstage.c

@@ -172,7 +172,6 @@ static void rcba_config(void)
 	RCBA32(FD) = reg32;
 }
 
-void main(FSP_INFO_HEADER *fsp_info_header); // XXX find a better place dorothy
 void main(FSP_INFO_HEADER *fsp_info_header)
 {
 #if IS_ENABLED(CONFIG_HAVE_ACPI_RESUME)

src/northbridge/intel/fsp_sandybridge/fsp/chipset_fsp_util.h

@@ -60,6 +60,9 @@
 #define FSP_IMAGE_ID_DWORD1 0x00505346
 #endif
 
+#ifdef __PRE_RAM__
+void main(FSP_INFO_HEADER *fsp_info_header);
 void romstage_main_continue(EFI_STATUS status, VOID *HobListPtr);
+#endif
 
 #endif /* CHIPSET_FSP_UTIL_H */

src/soc/intel/fsp_baytrail/baytrail/romstage.h

@@ -29,9 +29,9 @@ void report_platform_info(void);
 
 #include <stdint.h>
 #include <arch/cpu.h>
+#include <drivers/intel/fsp/fsp_util.h>
 
-#include <fsptypes.h>
-
+void main(FSP_INFO_HEADER *fsp_info_header);
 void romstage_main_continue(EFI_STATUS status, void *hob_list_ptr);
 uint32_t chipset_prev_sleep_state(uint32_t clear);
 

src/soc/intel/fsp_baytrail/romstage/romstage.c

@@ -152,7 +152,7 @@ static void baytrail_rtc_init(void)
 }
 
 /* Entry from cache-as-ram.inc. */
-void * asmlinkage main(FSP_INFO_HEADER *fsp_info_header)
+void main(FSP_INFO_HEADER *fsp_info_header)
 {
 	const unsigned long func_dis = PMC_BASE_ADDRESS + FUNC_DIS;
 	const unsigned long func_dis2 = PMC_BASE_ADDRESS + FUNC_DIS2;

src/southbridge/intel/fsp_rangeley/romstage.h

@@ -27,9 +27,9 @@
 
 #include <stdint.h>
 #include <arch/cpu.h>
+#include <drivers/intel/fsp/fsp_util.h>
 
-#include <fsptypes.h>
-
+void main(FSP_INFO_HEADER *fsp_info_header);
 void early_mainboard_romstage_entry(void);
 void late_mainboard_romstage_entry(void);
 void get_func_disables(uint32_t *mask);