assets: abstract away the firmware assets used for booting

As there can be more than one source of firmware assets this
patch generalizes the notion of locating a particular asset.
struct asset is added along with some helper functions for
working on assets as a first class citizen.

Change-Id: I2ce575d1e5259aed4c34c3dcfd438abe9db1d7b9
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10264
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins)

src/include/assets.h

@@ -0,0 +1,91 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2015 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc.
+ */
+#ifndef ASSETS_H
+#define ASSETS_H
+
+#include <region.h>
+
+/* An asset represents data used to boot the system. It can be found within
+ * CBFS or some other mechanism. While CBFS can be a source of an asset, note
+ * that using the asset API implies querying of other sources. */
+
+enum asset_type {
+	ASSET_UNKNOWN,
+	ASSET_VERSTAGE,
+	ASSET_ROMSTAGE,
+	ASSET_RAMSTAGE,
+	ASSET_REFCODE,
+	ASSET_PAYLOAD,
+	ASSET_BL31,
+};
+
+struct asset {
+	enum asset_type type;
+	const char *name;
+	struct region_device rdev;
+};
+
+static inline const char *asset_name(const struct asset *asset)
+{
+	return asset->name;
+}
+
+static inline enum asset_type asset_type(const struct asset *asset)
+{
+	return asset->type;
+}
+
+static struct region_device *asset_rdev(struct asset *asset)
+{
+	return &asset->rdev;
+}
+
+static inline size_t asset_size(const struct asset *asset)
+{
+	return region_device_sz(&asset->rdev);
+}
+
+/* Returns NULL on error. */
+static inline void *asset_mmap(const struct asset *asset)
+{
+	return rdev_mmap_full(&asset->rdev);
+}
+
+#define ASSET_INIT(type_, name_)	\
+	{				\
+		.type = (type_),	\
+		.name = (name_),	\
+	}
+
+/* Locate the asset as described by the parameter. It will query all known
+ * asset providers. Returns 0 on success. < 0 on error. */
+int asset_locate(struct asset *asset);
+
+struct asset_provider {
+	const char *name;
+	/* Determines if the provider is the active one. If so returns 1 else 0
+	 * or < 0 on error. */
+	int (*is_active)(struct asset *asset);
+	/* Returns < 0 on error or 0 on success. This function locates
+	 * the rdev representing the file data associated with the passed in
+	 * prog. */
+	int (*locate)(struct asset *asset);
+};
+
+#endif /* ASSETS_H */

src/include/program_loading.h

@@ -22,7 +22,7 @@
 
 #include <stdint.h>
 #include <stddef.h>
-#include <region.h>
+#include <assets.h>
 
 enum {
 	/* Last segment of program. Can be used to take different actions for
@@ -34,40 +34,49 @@ enum {
  * set on the last segment loaded. */
 void arch_segment_loaded(uintptr_t start, size_t size, int flags);
 
-enum prog_type {
-	PROG_VERSTAGE,
-	PROG_ROMSTAGE,
-	PROG_RAMSTAGE,
-	PROG_REFCODE,
-	PROG_PAYLOAD,
-	PROG_BL31,
-};
-
 /* Representation of a program. */
 struct prog {
-	enum prog_type type;
-	const char *name;
-	/* Source of program content to load. After loading program it
-	 * represents the memory region of the stages and payload. For
-	 * architectures that use a bounce buffer then it would represent
-	 * the bounce buffer. */
-	struct region_device rdev;
+	/* The region_device within the asset is the source of program content
+	 * to load. After loading program it represents the memory region of
+	 * the stages and payload. For architectures that use a bounce buffer
+	 * then it would represent the bounce buffer. */
+	struct asset asset;
 	/* Entry to program with optional argument. It's up to the architecture
 	 * to decide if argument is passed. */
 	void (*entry)(void *);
 	void *arg;
 };
 
+#define PROG_INIT(type_, name_)				\
+	{						\
+		.asset = ASSET_INIT(type_, name_),	\
+	}
+
+static inline const char *prog_name(const struct prog *prog)
+{
+	return asset_name(&prog->asset);
+}
+
+static inline enum asset_type prog_type(const struct prog *prog)
+{
+	return asset_type(&prog->asset);
+}
+
+static inline struct region_device *prog_rdev(struct prog *prog)
+{
+	return asset_rdev(&prog->asset);
+}
+
 /* Only valid for loaded programs. */
 static inline size_t prog_size(const struct prog *prog)
 {
-	return region_device_sz(&prog->rdev);
+	return asset_size(&prog->asset);
 }
 
 /* Only valid for loaded programs. */
 static inline void *prog_start(const struct prog *prog)
 {
-	return rdev_mmap_full(&prog->rdev);
+	return asset_mmap(&prog->asset);
 }
 
 static inline void *prog_entry(const struct prog *prog)
@@ -86,7 +95,7 @@ extern const struct mem_region_device addrspace_32bit;
 static inline void prog_memory_init(struct prog *prog, uintptr_t ptr,
 					size_t size)
 {
-	rdev_chain(&prog->rdev, &addrspace_32bit.rdev, ptr, size);
+	rdev_chain(&prog->asset.rdev, &addrspace_32bit.rdev, ptr, size);
 }
 
 static inline void prog_set_area(struct prog *prog, void *start, size_t size)
@@ -101,7 +110,11 @@ static inline void prog_set_entry(struct prog *prog, void *e, void *arg)
 }
 
 /* Locate the identified program to run. Return 0 on success. < 0 on error. */
-int prog_locate(struct prog *prog);
+static inline int prog_locate(struct prog *prog)
+{
+	return asset_locate(&prog->asset);
+}
+
 /* Run the program described by prog. */
 void prog_run(struct prog *prog);
 /* Per architecture implementation running a program. */