cbfs: new API and better program loading

A new CBFS API is introduced to allow making CBFS access
easier for providing multiple CBFS sources. That is achieved
by decoupling the cbfs source from a CBFS file. A CBFS
source is described by a descriptor. It contains the necessary
properties for walking a CBFS to locate a file. The CBFS
file is then decoupled from the CBFS descriptor in that it's
no longer needed to access the contents of the file.

All of this is accomplished using the regions infrastructure
by repsenting CBFS sources and files as region_devices. Because
region_devices can be chained together forming subregions this
allows one to decouple a CBFS source from a file. This also allows
one to provide CBFS files that came from other sources for
payload and/or stage loading.

The program loading takes advantage of those very properties
by allowing multiple sources for locating a program. Because of
this we can reduce the overhead of loading programs because
it's all done in the common code paths. Only locating the
program is per source.

Change-Id: I339b84fce95f03d1dbb63a0f54a26be5eb07f7c8
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/9134
Tested-by: build bot (Jenkins)
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

1 files changed, 53 insertions, 96 deletions

diff --git a/src/vendorcode/google/chromeos/vboot2/vboot_loader.c b/src/vendorcode/google/chromeos/vboot2/vboot_loader.c
index 226578bc8c..5248305a04 100644
--- a/src/vendorcode/google/chromeos/vboot2/vboot_loader.c
+++ b/src/vendorcode/google/chromeos/vboot2/vboot_loader.c
@@ -98,7 +98,8 @@ static int vboot_loader_active(struct prog *prog)
 		printk(BIOS_DEBUG, "VBOOT: Loading verstage.\n");
 
 		/* load verstage from RO */
-		if (cbfs_load_prog_stage(CBFS_DEFAULT_MEDIA, &verstage))
+		if (cbfs_boot_locate(&verstage.rdev, verstage.name, NULL) ||
+		    cbfs_prog_stage_load(&verstage))
 			die("failed to load verstage");
 
 		/* verify and select a slot */
@@ -118,29 +119,34 @@ static int vboot_loader_active(struct prog *prog)
 
 	wd = vboot_get_working_data();
 
-	if (vboot_is_slot_selected(wd)) {
-		if (IS_ENABLED(CONFIG_MULTIPLE_CBFS_INSTANCES) &&
-		    run_verification) {
-			/* RW A or B */
-			struct region_device fw_main;
-
-			if (vb2_get_selected_region(wd, &fw_main))
-				die("failed to reference selected region\n");
-			cbfs_set_header_offset(region_device_offset(&fw_main));
-		}
+	if (vboot_is_slot_selected(wd))
 		return 1;
-	}
 
 	return 0;
 }
 
-static int vboot_fw_region(int fw_index, const struct region_device *fw_main,
-				struct region_device *fw)
+static int vboot_locate_by_components(const struct region_device *fw_main,
+					struct prog *prog)
 {
 	struct vboot_components *fw_info;
 	size_t metadata_sz;
 	size_t offset;
 	size_t size;
+	struct region_device *fw = &prog->rdev;
+	int fw_index = 0;
+
+	if (prog->type == PROG_ROMSTAGE)
+		fw_index = CONFIG_VBOOT_ROMSTAGE_INDEX;
+	else if (prog->type == PROG_RAMSTAGE)
+		fw_index = CONFIG_VBOOT_RAMSTAGE_INDEX;
+	else if (prog->type == PROG_PAYLOAD)
+		fw_index = CONFIG_VBOOT_BOOT_LOADER_INDEX;
+	else if (prog->type == PROG_REFCODE)
+		fw_index = CONFIG_VBOOT_REFCODE_INDEX;
+	else if (prog->type == PROG_BL31)
+		fw_index = CONFIG_VBOOT_BL31_INDEX;
+	else
+		die("Invalid program type for vboot.");
 
 	metadata_sz = sizeof(*fw_info);
 	metadata_sz += MAX_PARSED_FW_COMPONENTS * sizeof(fw_info->entries[0]);
@@ -153,7 +159,7 @@ static int vboot_fw_region(int fw_index, const struct region_device *fw_main,
 	}
 
 	if (fw_index >= fw_info->num_components) {
-		printk(BIOS_INFO, "invalid stage index: %d\n", fw_index);
+		printk(BIOS_INFO, "invalid index: %d\n", fw_index);
 		rdev_munmap(fw_main, fw_info);
 		return -1;
 	}
@@ -163,16 +169,44 @@ static int vboot_fw_region(int fw_index, const struct region_device *fw_main,
 	rdev_munmap(fw_main, fw_info);
 
 	if (rdev_chain(fw, fw_main, offset, size)) {
-		printk(BIOS_INFO, "invalid stage address or size\n");
+		printk(BIOS_INFO, "invalid offset or size\n");
 		return -1;
 	}
 
 	return 0;
 }
 
+static int vboot_locate_by_multi_cbfs(const struct region_device *fw_main,
+					struct prog *prog)
+{
+	struct cbfsd cbfs;
+	struct region_device rdev;
+	struct cbfs_props props;
+
+	if (cbfs_boot_region_properties(&props))
+		return -1;
+
+	if (rdev_chain(&rdev, fw_main, props.offset, props.size))
+		return -1;
+
+	cbfs.rdev = &rdev;
+	cbfs.align = props.align;
+
+	return cbfs_locate(&prog->rdev, &cbfs, prog->name, NULL);
+}
+
+static int vboot_prog_locate(const struct region_device *fw_main,
+				struct prog *prog)
+{
+	if (IS_ENABLED(CONFIG_MULTIPLE_CBFS_INSTANCES))
+		return vboot_locate_by_multi_cbfs(fw_main, prog);
+	else
+		return vboot_locate_by_components(fw_main, prog);
+}
+
 /* This function is only called when vboot_loader_active() returns 1. That
  * means we are taking vboot paths. */
-static int vboot_prepare(struct prog *prog)
+static int vboot_locate(struct prog *prog)
 {
 	struct vb2_working_data *wd;
 	struct region_device fw_main;
@@ -183,92 +217,15 @@ static int vboot_prepare(struct prog *prog)
 	if (verstage_should_load() && !IS_ENABLED(CONFIG_RETURN_FROM_VERSTAGE))
 		return 0;
 
-	/* In the multi cbfs case the cbfs offset pointer has already been
-	 * updated after firmware verification. */
-	if (IS_ENABLED(CONFIG_MULTIPLE_CBFS_INSTANCES)) {
-		if (!ENV_RAMSTAGE &&
-		    cbfs_load_prog_stage(CBFS_DEFAULT_MEDIA, prog) != 0)
-			return -1;
-
-		/* Need to load payload. */
-		if (ENV_RAMSTAGE) {
-			void *payload;
-			size_t size;
-
-			payload = cbfs_get_file_content(CBFS_DEFAULT_MEDIA,
-							prog->name,
-							CBFS_TYPE_PAYLOAD,
-							&size);
-
-			if (payload == NULL)
-				die("Couldn't load payload\n");
-
-			prog_set_area(prog, payload, size);
-		}
-		return 0;
-	}
-
 	wd = vboot_get_working_data();
 	if (vb2_get_selected_region(wd, &fw_main))
 		die("failed to reference selected region\n");
 
-	/* Load payload in ramstage. */
-	if (ENV_RAMSTAGE) {
-		struct region_device payload;
-		void *payload_ptr;
-
-		if (vboot_fw_region(CONFIG_VBOOT_BOOT_LOADER_INDEX,
-						&fw_main, &payload))
-			die("Couldn't load payload.");
-
-		payload_ptr = rdev_mmap_full(&payload);
-
-		if (payload_ptr == NULL)
-			die("Couldn't load payload.");
-
-		prog_set_area(prog, payload_ptr, region_device_sz(&payload));
-	} else {
-		struct region_device stage;
-		int stage_index = 0;
-
-		if (prog->type == PROG_ROMSTAGE)
-			stage_index = CONFIG_VBOOT_ROMSTAGE_INDEX;
-		else if (prog->type == PROG_RAMSTAGE)
-			stage_index = CONFIG_VBOOT_RAMSTAGE_INDEX;
-		else
-			die("Invalid program type for vboot.");
-
-		if (vboot_fw_region(stage_index, &fw_main, &stage))
-			die("Vboot stage load failed.");
-
-		if (ENV_ROMSTAGE && IS_ENABLED(CONFIG_RELOCATABLE_RAMSTAGE)) {
-			void *stage_ptr;
-			struct rmod_stage_load rmod_ram = {
-				.cbmem_id = CBMEM_ID_RAMSTAGE,
-				.prog = prog,
-			};
-
-			stage_ptr = rdev_mmap_full(&stage);
-
-			if (stage_ptr == NULL)
-				die("Vboot couldn't load stage.");
-
-			if (rmodule_stage_load(&rmod_ram, stage_ptr))
-				die("Vboot couldn't load stage");
-		} else {
-			size_t offset = region_device_offset(&stage);
-
-			if (cbfs_load_prog_stage_by_offset(CBFS_DEFAULT_MEDIA,
-								prog, offset))
-				die("Vboot couldn't load stage");
-		}
-	}
-
-	return 0;
+	return vboot_prog_locate(&fw_main, prog);
 }
 
 const struct prog_loader_ops vboot_loader = {
 	.name = "VBOOT",
 	.is_loader_active = vboot_loader_active,
-	.prepare = vboot_prepare,
+	.locate = vboot_locate,
 };