cbfstool: Do host space address conversion earlier when adding files

In cbfs_add_component(), the |offset| variable confusingly jumps back
and forth between host address space and flash address space in some
cases. This patch tries to clean that logic up a bit by converting it
to flash address space very early in the function, and then keeping it
that way afterwards. convert() implementations that need the host
address space value should store it in a different variable to reduce
the risk of confusion. This should also fix a tiny issue where
--gen-attribute might have previously encoded the base address as given
in CBFS -- it probably makes more sense to always have it store a
consistent format (i.e. always flash address).

Also revert the unnecessary check for --base-address in
add_topswap_bootblock() that was added in CB:59877. On closer
inspection, the function actually doesn't use the passed in *offset at
all and uses it purely as an out-parameter. So while our current
Makefile does pass --base-address when adding the bootblock, it actually
has no effect and is redundant for the topswap case.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Idf4721c5b0700789ddb81c1618d740b3e7f486cb
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60018
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>

util/cbfstool/cbfstool.c

@@ -779,11 +779,6 @@ static int add_topswap_bootblock(struct buffer *buffer, uint32_t *offset)
 {
 	size_t bb_buf_size = buffer_size(buffer);
 
-	if (!param.baseaddress_assigned) {
-		ERROR("--topswap-size must also have --base-address\n");
-		return 1;
-	}
-
 	if (bb_buf_size > param.topswap_size) {
 		ERROR("Bootblock bigger than the topswap boundary\n");
 		ERROR("size = %zd, ts = %d\n", bb_buf_size,
@@ -826,7 +821,9 @@ static int cbfs_add_component(const char *filename,
 	/*
 	 * The steps used to determine the final placement offset in CBFS, in order:
 	 *
-	 * 1. If --base-address was passed, that value is used.
+	 * 1. If --base-address was passed, that value is used. If it was passed in the host
+	 *    address space, convert it to flash address space. (After that, |*offset| is always
+	 *    in the flash address space.)
 	 *
 	 * 2. The convert() function may write a location back to |offset|, usually by calling
 	 *    do_cbfs_locate(). In this case, it needs to ensure that the location found can fit
@@ -909,6 +906,10 @@ static int cbfs_add_component(const char *filename,
 		if (add_topswap_bootblock(&buffer, &offset))
 			goto error;
 
+	/* With --base-address we allow host space addresses -- if so, convert it here. */
+	if (IS_HOST_SPACE_ADDRESS(offset))
+		offset = convert_addr_space(param.image_region, offset);
+
 	if (convert && convert(&buffer, &offset, header) != 0) {
 		ERROR("Failed to parse file '%s'.\n", filename);
 		goto error;
@@ -975,9 +976,6 @@ static int cbfs_add_component(const char *filename,
 			goto error;
 	}
 
-	if (IS_HOST_SPACE_ADDRESS(offset))
-		offset = convert_addr_space(param.image_region, offset);
-
 	if (cbfs_add_entry(&image, &buffer, offset, header, len_align) != 0) {
 		ERROR("Failed to add '%s' into ROM image.\n", filename);
 		goto error;
@@ -1060,10 +1058,12 @@ static int cbfstool_convert_fsp(struct buffer *buffer,
 	 * There are 4 different cases here:
 	 *
 	 * 1. --xip and --base-address: we need to place the binary at the given base address
-	 *    in the CBFS image and relocate it to that address. *offset was already filled in.
+	 *    in the CBFS image and relocate it to that address. *offset was already filled in,
+	 *    but we need to convert it to the host address space for relocation.
 	 *
 	 * 2. --xip but no --base-address: we implicitly force a 4K minimum alignment so that
 	 *    relocation can occur. Call do_cbfs_locate() here to find an appropriate *offset.
+	 *    This also needs to be converted to the host address space for relocation.
 	 *
 	 * 3. No --xip but a --base-address: special case where --base-address does not have its
 	 *    normal meaning, instead we use it as the relocation target address. We explicitly
@@ -1079,10 +1079,8 @@ static int cbfstool_convert_fsp(struct buffer *buffer,
 			if (do_cbfs_locate(offset, 0))
 				return -1;
 		}
-		if (!IS_HOST_SPACE_ADDRESS(*offset))
+		assert(!IS_HOST_SPACE_ADDRESS(*offset));
 		address = convert_addr_space(param.image_region, *offset);
-		else
-			address = *offset;
 	} else {
 		if (param.baseaddress_assigned == 0) {
 			INFO("Honoring pre-linked FSP module, no relocation.\n");
@@ -1143,16 +1141,10 @@ static int cbfstool_convert_mkstage(struct buffer *buffer, uint32_t *offset,
 		return -1;
 
 	if (param.stage_xip) {
-		/*
+		uint32_t host_space_address = convert_addr_space(param.image_region, *offset);
-		 * Ensure the address is a memory mapped one. This assumes
+		assert(IS_HOST_SPACE_ADDRESS(host_space_address));
-		 * x86 semantics about the boot media being directly mapped
+		ret = parse_elf_to_xip_stage(buffer, &output, host_space_address,
-		 * below 4GiB in the CPU address space.
+					     param.ignore_section, stageheader);
-		 **/
-		*offset = convert_addr_space(param.image_region, *offset);
-
-		ret = parse_elf_to_xip_stage(buffer, &output, *offset,
-					     param.ignore_section,
-					     stageheader);
 	} else {
 		ret = parse_elf_to_stage(buffer, &output, param.ignore_section,
 					 stageheader);