cbmem.h: Change return type of cbmem_get_region

The underlying IMD function already returns an integer which indicates
success or failure.

This removes the need to have initialized variables that need to be
checked for NULL later. In some cases this actually adds the appropriate
check for returned values.

Dying is appropriate if cbmem is not found as it is essential to the
bootflow.

Change-Id: Ib3e09a75380faf9f533601368993261f042422ef
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84039
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

7 files changed, 23 insertions, 15 deletions

diff --git a/src/arch/x86/postcar_loader.c b/src/arch/x86/postcar_loader.c
index 2d7bb48d7d..aac4af8568 100644
--- a/src/arch/x86/postcar_loader.c
+++ b/src/arch/x86/postcar_loader.c
@@ -147,7 +147,8 @@ static void postcar_flush_cache(void)
 	uintptr_t stage_cache_base;
 	size_t stage_cache_size;
 
-	cbmem_get_region((void **)&cbmem_base, &cbmem_size);
+	if (cbmem_get_region((void **)&cbmem_base, &cbmem_size))
+		die("Could not find cbmem region");
 	prog_segment_loaded(cbmem_base, cbmem_size, SEG_FINAL);
 	if (CONFIG(TSEG_STAGE_CACHE) && !romstage_handoff_is_resume()) {
 		stage_cache_external_region((void **)&stage_cache_base, &stage_cache_size);
diff --git a/src/include/cbmem.h b/src/include/cbmem.h
index de305ae0a0..fd258cda4e 100644
--- a/src/include/cbmem.h
+++ b/src/include/cbmem.h
@@ -102,7 +102,7 @@ void cbmem_run_init_hooks(int is_recovery);
 /* Add the cbmem memory used to the memory map at boot. */
 void cbmem_add_bootmem(void);
 /* Return the cbmem memory used */
-void cbmem_get_region(void **baseptr, size_t *size);
+int cbmem_get_region(void **baseptr, size_t *size);
 void cbmem_list(void);
 void cbmem_add_records_to_cbtable(struct lb_header *header);
 
diff --git a/src/lib/fit_payload.c b/src/lib/fit_payload.c
index 21bc4e87ed..aea1ba75e9 100644
--- a/src/lib/fit_payload.c
+++ b/src/lib/fit_payload.c
@@ -110,8 +110,8 @@ static void add_cb_fdt_data(struct device_tree *tree)
 {
 	u32 addr_cells = 1, size_cells = 1;
 	u64 reg_addrs[2], reg_sizes[2];
-	void *baseptr = NULL;
-	size_t size = 0;
+	void *baseptr;
+	size_t size;
 
 	static const char *firmware_path[] = {"firmware", NULL};
 	struct device_tree_node *firmware_node = dt_find_node(tree->root,
@@ -140,8 +140,7 @@ static void add_cb_fdt_data(struct device_tree *tree)
 
 	/* Second is the CBMEM area (which usually includes the coreboot
 	table). */
-	cbmem_get_region(&baseptr, &size);
-	if (!baseptr || size == 0) {
+	if (cbmem_get_region(&baseptr, &size)) {
 		printk(BIOS_WARNING, "FIT: CBMEM pointer/size not found!\n");
 		return;
 	}
diff --git a/src/lib/imd_cbmem.c b/src/lib/imd_cbmem.c
index a88cf98d6c..2fc54bfff7 100644
--- a/src/lib/imd_cbmem.c
+++ b/src/lib/imd_cbmem.c
@@ -193,16 +193,19 @@ void *cbmem_entry_start(const struct cbmem_entry *entry)
 
 void cbmem_add_bootmem(void)
 {
-	void *baseptr = NULL;
-	size_t size = 0;
+	void *baseptr;
+	size_t size;
 
-	cbmem_get_region(&baseptr, &size);
+	if (cbmem_get_region(&baseptr, &size)) {
+		printk(BIOS_ERR, "CBMEM pointer/size not found!\n");
+		return;
+	}
 	bootmem_add_range((uintptr_t)baseptr, size, BM_MEM_TABLE);
 }
 
-void cbmem_get_region(void **baseptr, size_t *size)
+int cbmem_get_region(void **baseptr, size_t *size)
 {
-	imd_region_used(&imd, baseptr, size);
+	return imd_region_used(&imd, baseptr, size);
 }
 
 #if ENV_PAYLOAD_LOADER || (CONFIG(EARLY_CBMEM_LIST) && ENV_HAS_CBMEM)
diff --git a/src/security/memory/memory_clear.c b/src/security/memory/memory_clear.c
index 9af3205b0e..9a8a23a1f7 100644
--- a/src/security/memory/memory_clear.c
+++ b/src/security/memory/memory_clear.c
@@ -74,12 +74,13 @@ static void clear_memory(void *unused)
 			BM_MEM_RAM);
 
 	/* Add reserved entries */
-	void *baseptr = NULL;
-	size_t size = 0;
+	void *baseptr;
+	size_t size;
 
 	/* Only skip CBMEM, stage program, stack and heap are included there. */
 
-	cbmem_get_region(&baseptr, &size);
+	if (cbmem_get_region(&baseptr, &size))
+		die("Could not find cbmem region");
 	memranges_insert(&mem, (uintptr_t)baseptr, size, BM_MEM_TABLE);
 
 	if (ENV_X86) {
diff --git a/src/soc/intel/xeon_sp/memmap.c b/src/soc/intel/xeon_sp/memmap.c
index bf4c13e4d3..b70c1cc75a 100644
--- a/src/soc/intel/xeon_sp/memmap.c
+++ b/src/soc/intel/xeon_sp/memmap.c
@@ -35,7 +35,8 @@ void fill_postcar_frame(struct postcar_frame *pcf)
 	size_t cbmem_size;
 
 	/* Try account for the CBMEM region currently used and for future use */
-	cbmem_get_region((void **)&cbmem_base, &cbmem_size);
+	if (cbmem_get_region((void **)&cbmem_base, &cbmem_size))
+		die("Could not find cbmem region");
 	printk(BIOS_DEBUG, "top_of_ram = 0x%lx\n", top_of_ram);
 	printk(BIOS_DEBUG, "cbmem base_ptr: 0x%lx, size: 0x%zx\n", cbmem_base, cbmem_size);
 	/* Assume 4MiB will be enough for future cbmem objects (FSP-S, ramstage, ...) */
diff --git a/tests/lib/Makefile.mk b/tests/lib/Makefile.mk
index 7fc5471529..1a96c7d620 100644
--- a/tests/lib/Makefile.mk
+++ b/tests/lib/Makefile.mk
@@ -55,6 +55,7 @@ hexstrtobin-test-srcs += src/lib/hexstrtobin.c
 imd-test-srcs += tests/lib/imd-test.c
 imd-test-srcs += tests/stubs/console.c
 imd-test-srcs += src/lib/imd.c
+imd-test-srcs += tests/stubs/die.c
 
 timestamp-test-srcs += tests/lib/timestamp-test.c
 timestamp-test-srcs += tests/stubs/timestamp.c
@@ -85,12 +86,14 @@ imd_cbmem-ramstage-test-srcs += tests/lib/imd_cbmem-test.c
 imd_cbmem-ramstage-test-srcs += tests/stubs/console.c
 imd_cbmem-ramstage-test-srcs += src/lib/imd.c
 imd_cbmem-ramstage-test-mocks += cbmem_top_chipset
+imd_cbmem-ramstage-test-srcs += tests/stubs/die.c
 
 imd_cbmem-romstage-test-stage := romstage
 imd_cbmem-romstage-test-srcs += tests/lib/imd_cbmem-test.c
 imd_cbmem-romstage-test-srcs += tests/stubs/console.c
 imd_cbmem-romstage-test-srcs += src/lib/imd.c
 imd_cbmem-romstage-test-mocks += cbmem_top_chipset
+imd_cbmem-romstage-test-srcs += tests/stubs/die.c
 
 region_file-test-srcs += tests/lib/region_file-test.c
 region_file-test-srcs += src/commonlib/region.c