Commit Graph

171 Commits

Author SHA1 Message Date
Wolfgang Denk
ea882baf9c New implementation for internal handling of environment variables.
Motivation:

* Old environment code used a pessimizing implementation:
  - variable lookup used linear search => slow
  - changed/added variables were added at the end, i. e. most
    frequently used variables had the slowest access times => slow
  - each setenv() would calculate the CRC32 checksum over the whole
    environment block => slow
* "redundant" envrionment was locked down to two copies
* No easy way to implement features like "reset to factory defaults",
  or to select one out of several pre-defined (previously saved) sets
  of environment settings ("profiles")
* No easy way to import or export environment settings

======================================================================

API Changes:

- Variable names starting with '#' are no longer allowed

  I didn't find any such variable names being used; it is highly
  recommended to follow standard conventions and start variable names
  with an alphanumeric character

- "printenv" will now print a backslash at the end of all but the last
  lines of a multi-line variable value.

  Multi-line variables have never been formally defined, allthough
  there is no reason not to use them. Now we define rules how to deal
  with them, allowing for import and export.

- Function forceenv() and the related code in saveenv() was removed.
  At the moment this is causing build problems for the only user of
  this code (schmoogie - which has no entry in MAINTAINERS); may be
  fixed later by implementing the "env set -f" feature.

Inconsistencies:

- "printenv" will '\\'-escape the '\n' in multi-line variables, while
  "printenv var" will not do that.

======================================================================

Advantages:

- "printenv" output much better readable (sorted)
- faster!
- extendable (additional variable properties can be added)
- new, powerful features like "factory reset" or easy switching
  between several different environment settings ("profiles")

Disadvantages:

- Image size grows by typically 5...7 KiB (might shrink a bit again on
  systems with redundant environment with a following patch series)

======================================================================

Implemented:

- env command with subcommands:

  - env print [arg ...]

    same as "printenv": print environment

  - env set [-f] name [arg ...]

    same as "setenv": set (and delete) environment variables

    ["-f" - force setting even for read-only variables - not
    implemented yet.]

  - end delete [-f] name

    not implemented yet

    ["-f" - force delete even for read-only variables]

  - env save

    same as "saveenv": save environment

  - env export [-t | -b | -c] addr [size]

    export internal representation (hash table) in formats usable for
    persistent storage or processing:

	-t:	export as text format; if size is given, data will be
		padded with '\0' bytes; if not, one terminating '\0'
		will be added (which is included in the "filesize"
		setting so you can for exmple copy this to flash and
		keep the termination).
	-b:	export as binary format (name=value pairs separated by
		'\0', list end marked by double "\0\0")
	-c:	export as checksum protected environment format as
		used for example by "saveenv" command
	addr:	memory address where environment gets stored
	size:	size of output buffer

	With "-c" and size is NOT given, then the export command will
	format the data as currently used for the persistent storage,
	i. e. it will use CONFIG_ENV_SECT_SIZE as output block size and
	prepend a valid CRC32 checksum and, in case of resundant
	environment, a "current" redundancy flag. If size is given, this
	value will be used instead of CONFIG_ENV_SECT_SIZE; again, CRC32
	checksum and redundancy flag will be inserted.

	With "-b" and "-t", always only the real data (including a
	terminating '\0' byte) will be written; here the optional size
	argument will be used to make sure not to overflow the user
	provided buffer; the command will abort if the size is not
	sufficient. Any remainign space will be '\0' padded.

        On successful return, the variable "filesize" will be set.
        Note that filesize includes the trailing/terminating '\0'
        byte(s).

        Usage szenario: create a text snapshot/backup of the current
	settings:

		=> env export -t 100000
		=> era ${backup_addr} +${filesize}
		=> cp.b 100000 ${backup_addr} ${filesize}

	Re-import this snapshot, deleting all other settings:

		=> env import -d -t ${backup_addr}

  - env import [-d] [-t | -b | -c] addr [size]

    import external format (text or binary) into hash table,
    optionally deleting existing values:

	-d:	delete existing environment before importing;
		otherwise overwrite / append to existion definitions
	-t:	assume text format; either "size" must be given or the
		text data must be '\0' terminated
	-b:	assume binary format ('\0' separated, "\0\0" terminated)
	-c:	assume checksum protected environment format
	addr:	memory address to read from
	size:	length of input data; if missing, proper '\0'
		termination is mandatory

  - env default -f

    reset default environment: drop all environment settings and load
    default environment

  - env ask name [message] [size]

    same as "askenv": ask for environment variable

  - env edit name

    same as "editenv": edit environment variable

  - env run

    same as "run": run commands in an environment variable

======================================================================

TODO:

- drop default env as implemented now; provide a text file based
  initialization instead (eventually using several text files to
  incrementally build it from common blocks) and a tool to convert it
  into a binary blob / object file.

- It would be nice if we could add wildcard support for environment
  variables; this is needed for variable name auto-completion,
  but it would also be nice to be able to say "printenv ip*" or
  "printenv *addr*"

- Some boards don't link any more due to the grown code size:
  DU405, canyonlands, sequoia, socrates.

	=> cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
	       Stefan Roese <sr@denx.de>,
	       Heiko Schocher <hs@denx.de>

- Dropping forceenv() causes build problems on schmoogie

	=> cc: Sergey Kubushyn <ksi@koi8.net>

- Build tested on PPC and ARM only; runtime tested with NOR and NAND
  flash only => needs testing!!

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
Cc: Stefan Roese <sr@denx.de>,
Cc: Heiko Schocher <hs@denx.de>
Cc: Sergey Kubushyn <ksi@koi8.net>
2010-09-19 19:29:48 +02:00
Wolfgang Denk
91a76751a0 Make getenv() work before relocation.
So far, getenv() would work before relocation is most cases, even
though it was not intended to be used that way.  When switching to a
hash table based implementation, this would break a number of boards.

For convenience, we make getenv() check if it's running before
relocation and, if so, use getenv_f() internally.

Note that this is limited to simple cases, as we use a small static
buffer (32 bytes) in the global data for this purpose.

For this reason, it is also not a good idea to convert all current
uses of getenv_f() into getenv() - some of the existing use cases need
to be able to deal with longer variable values, so getenv_f() is still
needed and recommended for use before relocation.

Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:48 +02:00
Thomas Chou
7a6a7d10e6 nios2: fix out of reach case for do_reset
There is a limitation (or bug?) of nios2 toolchain. The nios2 gcc
didn't generate correct code when the reset vector is passed as a
constant. It just generated a direct "call", which was wrong when
the reset vector was not located in the same 256MB span as u-boot.

The "Nios II Processor Reference Handbook" said,
"call can transfer execution anywhere within the 256 MByte range
determined by PC31..28. The Nios II GNU linker does not automatically
handle cases in which the address is out of this range."

So we have to use registered "callr" instruction to do the job.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-08-19 22:15:49 -04:00
Thomas Chou
62a0557382 nios2: fix bootm error on fdt args
We should check argv[3] only if there are enough args. Otherwise,
it might cause invalid memory access fault.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-08-19 22:15:49 -04:00
Thomas Chou
6db6c18b50 nios2: add gpio_request
This will be used by nand_plat.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-07-12 11:30:51 -04:00
Thomas Chou
06c5d30dc3 nios2: add fdt support
This patch adds fdt support to boot linux, followed Michal's
work on microblaze.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-07-12 11:30:51 -04:00
Thomas Chou
cb2da50f0f nios2: use gc sections to reduce image size
Follow the discussion of Charles Manning and Mike Frysinger.
Using gc_sections helps reduce image size.

Configuring for nios2-generic board...
Before,
   text    data     bss     dec     hex filename
 123979    3724   22892  150595   24c43 /tmp/u-boot/u-boot
After,
   text    data     bss     dec     hex filename
 115983    3800   22732  142515   22cb3 /tmp/u-boot/u-boot

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-07-12 11:30:51 -04:00
Wolfgang Denk
54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00
Thomas Chou
6803336c9f nios2: allow STANDALONE_LOAD_ADDR overriding
This patch allows users to override default STANDALONE_LOAD_ADDR.
The gcclibdir path was duplicated in the standalone Makefile and
can be removed.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-05-28 10:56:04 -04:00
Thomas Chou
8d52ea6db4 nios2: fix div64 issue for gcc4
This patch fixes the run-time error on div64 when built with
gcc4, which was reported by jhwu0625 on nios forum. It merges
math support from libgcc of gcc4. This patch is copied from
nios2-linux.

It works with both gcc3 and gcc4. The old mult.c, divmod.c and
math.h are removed.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-05-28 10:56:03 -04:00
Thomas Chou
0df01fd3d7 nios2: fix r15 issue for gcc4
The "-ffixed-r15" option doesn't work well for gcc4. Since we
don't use gp for small data with option "-G0", we can use gp
as global data pointer. This allows compiler to use r15. It
is necessary for gcc4 to work properly.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-05-28 10:56:03 -04:00
Thomas Chou
cedd341d55 nios2: add gpio support
This patch adds driver for a trivial gpio core, which is described
in http://nioswiki.com/GPIO. It is used for gpio led and nand flash
interface in u-boot.

When CONFIG_SYS_GPIO_BASE is not defined, board may provide
its own driver.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Tested-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-05-28 10:56:03 -04:00
Thomas Chou
441cac10d8 nios2: fix no flash, add nand and mmc init in board.c
This patch fixes error when CONFIG_SYS_NO_FLASH. And adds
nand flash and mmc initialization, which should go before
env initialization.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-24 18:21:23 -04:00
Thomas Chou
fd2712d0b1 nios2: consolidate reset initialization
Global interrupt should be disabled from the beginning.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-24 18:21:23 -04:00
Thomas Chou
7e812f2e9c nios2: add dma_alloc_coherent
This function return cache-line aligned allocation which is mapped
to uncached io region.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-24 18:21:22 -04:00
Thomas Chou
0dc1c7f692 nios2: add 64 bits swab support
This patch adds 64 bits swab support. Most 32 bits processors use
this. We need 64 bits swab for UBI.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-24 18:21:22 -04:00
Thomas Chou
dd168ef5b8 nios2: allow link script overriding from boards
This patch allow boards to override the default link script.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-24 18:21:22 -04:00
Scott McNutt
254ab7bd46 nios2: Move individual board linker scripts to common script in cpu tree.
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
2010-04-16 16:12:39 -04:00
Peter Tyser
37e4dafaae nios2: Move cpu/nios2/* to arch/nios2/cpu/*
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:27 +02:00
Peter Tyser
819833af39 Move architecture-specific includes to arch/$ARCH/include/asm
This helps to clean up the include/ directory so that it only contains
non-architecture-specific headers and also matches Linux's directory
layout which many U-Boot developers are already familiar with.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:12 +02:00
Peter Tyser
ea0364f1bb Move lib_$ARCH directories to arch/$ARCH/lib
Also move lib_$ARCH/config.mk to arch/$ARCH/config.mk

This change is intended to clean up the top-level directory structure
and more closely mimic Linux's directory organization.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:03 +02:00