lib/fmap: Add optional pre-RAM cache

This patch adds an optional pre-RAM cache for the FMAP which most
platforms should be able to use, complementing the recently added
post-RAM FMAP cache in CBMEM. vboot systems currently read the FMAP
about half a dozen times from flash in verstage, which will all be
coalesced into a single read with this patch. It will also help
future vboot improvements since when FMAP reads become "free" vboot
doesn't need to keep track of so much information separately.

In order to make sure we have a single, well-defined point where the new
cache is first initialized, eliminate the build-time hardcoding of the
CBFS section offsets, so that all CBFS accesses explicitly read the
FMAP.

Add FMAP_CACHEs to all platforms that can afford it (other than the
RISC-V things where I have no idea how they work), trying to take the
space from things that look like they were oversized anyway (pre-RAM
consoles and CBFS caches).

Change-Id: I2820436776ef620bdc4481b5cd4b6957764248ea
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36657
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Joel Kitching <kitching@google.com>

1 files changed, 6 insertions, 17 deletions

diff --git a/util/cbfstool/fmaptool.c b/util/cbfstool/fmaptool.c
index faf65081fd..1c01ec0da9 100644
--- a/util/cbfstool/fmaptool.c
+++ b/util/cbfstool/fmaptool.c
@@ -24,6 +24,7 @@
 #define STDIN_FILENAME_SENTINEL "-"
 
 #define HEADER_FMAP_OFFSET "FMAP_OFFSET"
+#define HEADER_FMAP_SIZE "FMAP_SIZE"
 
 enum fmaptool_return {
 	FMAPTOOL_EXIT_SUCCESS = 0,
@@ -83,7 +84,8 @@ static void list_cbfs_section_names(FILE *out)
 }
 
 static bool write_header(const char *out_fname,
-					const struct flashmap_descriptor *root)
+			 const struct flashmap_descriptor *root,
+			 const int fmap_size)
 {
 	assert(out_fname);
 
@@ -100,21 +102,8 @@ static bool write_header(const char *out_fname,
 
 	fputs("#ifndef FMAPTOOL_GENERATED_HEADER_H_\n", header);
 	fputs("#define FMAPTOOL_GENERATED_HEADER_H_\n\n", header);
-	fprintf(header, "#define %s %#x\n\n", HEADER_FMAP_OFFSET, fmap_offset);
-
-	/* also add defines for each CBFS-carrying fmap region: base and size */
-	cbfs_section_iterator_t cbfs_it = cbfs_sections_iterator();
-	while (cbfs_it) {
-		const struct flashmap_descriptor *item =
-				cbfs_sections_iterator_deref(cbfs_it);
-		assert(item->offset_known && item->size_known);
-		unsigned abs_base = fmd_calc_absolute_offset(root, item->name);
-		fprintf(header, "#define ___FMAP__%s_BASE 0x%x\n",
-			item->name, abs_base);
-		fprintf(header, "#define ___FMAP__%s_SIZE 0x%x\n",
-			item->name, item->size);
-		cbfs_sections_iterator_advance(&cbfs_it);
-	}
+	fprintf(header, "#define %s %#x\n", HEADER_FMAP_OFFSET, fmap_offset);
+	fprintf(header, "#define %s %#x\n\n", HEADER_FMAP_SIZE, fmap_size);
 
 	fputs("#endif\n", header);
 
@@ -245,7 +234,7 @@ int main(int argc, char **argv)
 	fmap_destroy(flashmap);
 
 	if (args.header_filename &&
-			!write_header(args.header_filename, descriptor)) {
+			!write_header(args.header_filename, descriptor, size)) {
 		full_fmd_cleanup(&descriptor);
 		return FMAPTOOL_EXIT_FAILED_WRITING_HEADER;
 	}