Import

api/Makefile

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+#
+# (C) Copyright 2007 Semihalf
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# 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 Foundatio; either version 2 of
+# the License, or (at your option) any later version.
+#
+# 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., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+include $(TOPDIR)/config.mk
+
+LIB	= $(obj)libapi.o
+
+COBJS-$(CONFIG_API) += api.o api_display.o api_net.o api_storage.o \
+		       api_platform-$(ARCH).o
+
+COBJS	:= $(COBJS-y)
+SRCS	:= $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+
+$(LIB):	$(obj).depend $(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend

api/README

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+U-Boot machine/arch independent API for external apps
+=====================================================
+
+1.  Main assumptions
+
+  - there is a single entry point (syscall) to the API
+
+  - per current design the syscall is a C-callable function in the U-Boot
+    text, which might evolve into a real syscall using machine exception trap
+    once this initial version proves functional
+
+  - the consumer app is responsible for producing appropriate context (call
+    number and arguments)
+
+  - upon entry, the syscall dispatches the call to other (existing) U-Boot
+    functional areas like networking or storage operations
+
+  - consumer application will recognize the API is available by searching
+    a specified (assumed by convention) range of address space for the
+    signature
+
+  - the U-Boot integral part of the API is meant to be thin and non-intrusive,
+    leaving as much processing as possible on the consumer application side,
+    for example it doesn't keep states, but relies on hints from the app and
+    so on
+
+  - optional (CONFIG_API)
+
+
+2. Calls
+
+  - console related (getc, putc, tstc etc.)
+  - system (reset, platform info)
+  - time (delay, current)
+  - env vars (enumerate all, get, set)
+  - devices (enumerate all, open, close, read, write); currently two classes
+    of devices are recognized and supported: network and storage (ide, scsi,
+    usb etc.)
+
+
+3. Structure overview
+
+  - core API, integral part of U-Boot, mandatory
+    - implements the single entry point (mimics UNIX syscall)
+
+  - glue
+    - entry point at the consumer side, allows to make syscall, mandatory
+      part
+
+    - helper conveniency wrappers so that consumer app does not have to use
+      the syscall directly, but in a more friendly manner (a la libc calls),
+      optional part
+
+  - consumer application
+    - calls directly, or leverages the provided glue mid-layer