Commit graph

146 commits

Author SHA1 Message Date
Simon Glass
d9d7c20b73 treewide: Drop bootm_headers_t typedef
This is not needed and we should avoid typedefs. Use the struct instead.

Signed-off-by: Simon Glass <sjg@chromium.org>
2022-09-29 16:07:57 -04:00
Weijie Gao
2948d9cf86 mips: add support for noncached_alloc()
This patch adds support for noncached_alloc() which was only supported by
ARM platform.

Unlike the ARM platform, MMU is not used in u-boot for MIPS. Instead, KSEG
is provided to access uncached memory. So most code of this patch is copied
from cache.c of ARM platform, with only two differences:
1. MMU is untouched in noncached_set_region()
2. Address returned by noncached_alloc() is converted using KSEG1ADDR()

Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
2022-07-13 23:03:37 +02:00
Simon Glass
d67f9e35c4 mips: Avoid using config_enabled() directly
Use IS_ENABLED() instead, which is the correct macro for checking a CONFIG
option.

Signed-off-by: Simon Glass <sjg@chromium.org>
2022-02-08 23:07:59 -05:00
Marek Vasut
1f391c3454 lmb: Switch to generic arch_lmb_reserve_generic()
Switch arc/arm/m68k/microblaze/mips/ppc arch_lmb_reserve() to
arch_lmb_reserve_generic().

Reviewed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Alexey Brodkin <alexey.brodkin@synopsys.com>
Cc: Angelo Dureghello <angelo@sysam.it>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Cc: Hai Pham <hai.pham.ud@renesas.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tom Rini <trini@konsulko.com>
Cc: Wolfgang Denk <wd@denx.de>
2021-09-23 14:15:32 -04:00
Simon Glass
401d1c4f5d common: Drop asm/global_data.h from common header
Move this out of the common header and include it only where needed.  In
a number of cases this requires adding "struct udevice;" to avoid adding
another large header or in other cases replacing / adding missing header
files that had been pulled in, very indirectly.   Finally, we have a few
cases where we did not need to include <asm/global_data.h> at all, so
remove that include.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
2021-02-02 15:33:42 -05:00
Ovidiu Panait
130845bac1 common: board_r: Drop arch-specific ifdefs around initr_trap
In order to remove the arch-specific ifdefs around initr_trap, introduce
arch_initr_trap weak initcall. Implementations for ppc/m68k/mips have
been moved to arch/<arch>/lib/traps.c

Default implementation is a nop stub.

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2021-01-15 14:36:12 -05:00
Stefan Roese
e207f2256f global: Move from bi_memstart/memsize -> gd->ram_base/ram_size
With the planned removal of bi_memstart & bi_memsize, this patch now
moves the references to the better suiting gd->ram_base/ram_size
variables.

Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
2020-08-26 09:19:34 +02:00
Daniel Schwierzeck
81d4b14f7e mips: sync asm/mipsregs.h with Linux 5.7
Sync asm/mipsregs.h with Linux 5.7. Also replace the custom
symbols EBASE_CPUNUM and EBASE_WG with the according symbols
from Linux.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Daniel Schwierzeck
dd1bb42305 mips: remove deprecated UNCACHED_SDRAM() macro
This macro only served as a wrapper for CKSEG1ADDR() with an
exception for CONFIG_TB0229. CONFIG_TB0229 doesn't exist, thus
use CKSEG1ADDR() directly.

This also prepares for an upcoming asm header sync with Linux.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Daniel Schwierzeck
60772433dd mips: refactor disabling of caches
Logically this code belongs to cache_init.S.

If a complex SoC needs to replace the generic cache init,
mips_cache_disable() can now be called from custom start.S files.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Daniel Schwierzeck
b55e07e565 mips: add KSEG1 wrapper for change_k0_cca
change_k0_cca() is called multiple times. Move the code for
changing to KSEG1 to a macro to avoid code duplication.

Also fix missing change to KSEG1 when changing to CONF_CM_CACHABLE_COW.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Stefan Roese
60a0559b7f mips: cache: Make invalidate_dcache_range() weak to enable overwrite
This patch adds __weak to invalidate_dcache_range() in lib/cache.c. This
makes it possible to overwrite this function by a platforms specific
version, which will be done for Octeon.

Signed-off-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Stefan Roese
1d4ba15c6f mips: cache: Make flush_cache() weak to enable overwrite
This patch adds __weak to flush_cache() in lib/cache.c. This makes it
possible to overwrite this function by a platforms specific version,
like done with the Octeon base port.

Signed-off-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Stefan Roese
2eed3dca22 mips: cache: Allow using CONFIG_MIPS_L2_CACHE without CONFIG_MIPS_CM
This patch enables the usage of CONFIG_MIPS_L2_CACHE without
CONFIG_MIPS_CM, which is what is needed for the newly added Octeon
platform.

Signed-off-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Stefan Roese
c372813105 mips: reloc: Change R_MIPS_NONE to catch pre-reloc BSS usage
This patch changes the R_MIPS_NONE define from 0 to a magic value. This
makes it possible to better detect any forbidden pre-relocation usage
of BSS variables, as they are often zero'ed and then relocation is
stopped too early.

Additionally the error message is improved to also print the faulting
address. This helps finding the root-cause for this breakage by
comparing this address with the values in System.map.

This patch helps a lot when working on pre-relocation code, like the
Octeon DDR init code, where such variables have hit me multiple times
now.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
2020-07-18 14:23:25 +02:00
Stefan Roese
a02bc1f992 mips: traps: Set WG bit in EBase register on Octeon
WG (bit 11) needs to be set on Octeon to enable writing bits 63:30 of
the exception base register.

Signed-off-by: Stefan Roese <sr@denx.de>
2020-07-18 14:23:25 +02:00
Simon Glass
cd93d625fd common: Drop linux/bitops.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 21:19:23 -04:00
Simon Glass
eb41d8a1be common: Drop linux/bug.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 21:19:23 -04:00
Simon Glass
25a5818ff8 common: Drop asm/ptrace.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 21:19:23 -04:00
Simon Glass
f7ae49fc4f common: Drop log.h from common header
Move this header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 21:19:18 -04:00
Simon Glass
0914011310 command: Remove the cmd_tbl_t typedef
We should not use typedefs in U-Boot. They cannot be used as forward
declarations which means that header files must include the full header to
access them.

Drop the typedef and rename the struct to remove the _s suffix which is
now not useful.

This requires quite a few header-file additions.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 18:36:55 -04:00
Simon Glass
691d719db7 common: Drop init.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 17:33:33 -04:00
Simon Glass
4d72caa5b9 common: Drop image.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 17:33:33 -04:00
Simon Glass
52f2423804 common: Drop bootstage.h from common header
Move this fairly uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 17:33:33 -04:00
Simon Glass
90526e9fba common: Drop net.h from common header
Move this header out of the common header. Network support is used in
quite a few places but it still does not warrant blanket inclusion.

Note that this net.h header itself has quite a lot in it. It could be
split into the driver-mode support, functions, structures, checksumming,
etc.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 17:33:31 -04:00
Stefan Roese
2a9d68e41f mips: spl: Flush cache before jumping to U-Boot proper
This patch adds a MIPS specific jump_to_image_no_args() implementation,
which flushes the U-Boot proper image loaded from the boot device in
SPL before jumping to it.

It has been noticed on MT76x8, that this cache flush is needed. Other
MIPS platforms might need it as well.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Weijie Gao <weijie.gao@mediatek.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2020-04-27 20:29:33 +02:00
Weijie Gao
71059736b8 mips: add support to restore exception vector base before booting linux
In U-Boot the exception vector base will be moved to top of memory, to be
used to display register dump when exception occurs.

But some old linux kernel does not honor the base set in CP0_EBASE. A
modified exception vector base will cause kernel crash.

This patch adds an option to enable reset exception vector base to its
previous value, or a user configured value before booting linux kernel.

Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
2020-04-27 20:29:33 +02:00
Stefan Roese
fb9acad305 mips: cmd: go: Flush cache before jumping to app/image
It has been noticed on MT7628/88 platforms, that booting the RAM image
does not work reliably. Sometimes it works and sometimes not. Debugging
showed that this "might" be a cache related issue as very strange
errors occurred (e.g. output corrupted etc).

This patch adds a cache flush for the complete SDRAM area to the go cmd
before jumping to the entry point for the MIPS architecture. The
complete area is flushed as we don't know at this point, how big the
area of the "application" really is.

Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Tested-by: Mauro Condarelli <mc5686@mclink.it>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Mauro Condarelli <mc5686@mclink.it>
Cc: Weijie Gao <weijie.gao@mediatek.com>
2020-04-09 19:00:00 +02:00
Alex Nemirovsky
ebdc278954 MIPS: allow override of flush_dcache_range()
Useful in custom HW designs which have a need to flush dcache
range in a completely non standard way.

Signed-off-by: Alex Nemirovsky <alex.nemirovsky@cortina-access.com>
2020-04-09 18:55:59 +02:00
Simon Glass
db41d65a97 common: Move hang() to the same header as panic()
At present panic() is in the vsprintf.h header file. That does not seem
like an obvious choice for hang(), even though it relates to panic(). So
let's put hang() in its own header.

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Migrate a few more files]
Signed-off-by: Tom Rini <trini@konsulko.com>
2020-01-17 17:53:40 -05:00
Simon Glass
941338725d common: Move relocate_code() to init.h
This is an init function so move it out of the common header. Avoid using
the typedef so that we don't have to include the global_data header file.

Also tidy up the function style in comments while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-01-17 13:26:49 -05:00
Simon Glass
d67bdaa799 common: Move trap_init() out of common.h
Move this function into the init.h header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2019-12-02 18:25:25 -05:00
Simon Glass
1eb69ae498 common: Move ARM cache operations out of common.h
These functions are CPU-related and do not use driver model. Move them to
cpu_func.h

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:24:58 -05:00
Simon Glass
9edefc2776 common: Move some cache and MMU functions out of common.h
These functions belong in cpu_func.h. Another option would be cache.h
but that code uses driver model and we have not moved these cache
functions to use driver model. Since they are CPU-related it seems
reasonable to put them here.

Move them over.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:23:55 -05:00
Ramon Fried
22247c63ac MIPS: add compile time definition of L2 cache size
If configuration is set to skip low level init, automatic
probe of L2 cache size is not performed and the size is set to 0.
Flushing or invalidating the L2 cache will fail in this case.

Add a static configuration (SYS_DCACHE_LINE_SIZE) with default set to 0.

Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
2019-10-25 17:20:43 +02:00
Simon Glass
4bfd1f5d62 env: Move env_init() to env.h
Move env_init() over to the new header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
2019-08-11 16:43:41 -04:00
Horatiu Vultur
6943cc9732 arch: mips: Update initrd_start and initrd_end
Microsemi SoC defines CONFIG_SYS_SDRAM_BASE to be 0x80000000, which
represents the start of kseg0 and represents a virtual address. Meaning
that the initrd_start and initrd_end point somewhere kseg0.
When these parameters are passed to linux kernel through DT
they are pointing somewhere in kseg0 which is a virtual address but linux
kernel expects the addresses to be physical addresses(in kuseg) because
it is converting the physical address to a virtual one.

Therefore update the uboot to pass the physical address of initrd_start
and initrd_end by converting them using the function virt_to_phys before
setting up the DT.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2019-05-03 16:42:23 +02:00
Horatiu Vultur
e515166636 bootm: mips: Remove boot_reloc_ramdisk
Remove the function boot_reloc_ramdisk in the file arch/mips/lib/bootm
because it is relocating again the ramdisk. The function do_bootm_states()
already relocates the ramdisk even if it is a legacy uImage or a FIT image.

The relocation in the function do_bootm_states() was introduce in the
commit c2e7e72bb9 ("bootm: relocate ramdisk
if CONFIG_SYS_BOOT_RAMDISK_HIGH set")

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2019-04-12 17:32:50 +02:00
Daniel Schwierzeck
46203baf66 MIPS: cache: remove config option CONFIG_SYS_MIPS_CACHE_MODE
Caches should be configured to mode CONF_CM_CACHABLE_NONCOHERENT
(or CONF_CM_CACHABLE_COW when a CM is available). There is no
need to make this configurable.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-09-22 21:04:10 +02:00
Daniel Schwierzeck
5ef337a037 MIPS: cache: make index base address configurable
The index base address used for the cache initialisation is currently
hard-coded to CKSEG0. Make this value configurable if a MIPS system
needs to have a different address (e.g. in SRAM or ScratchPad RAM).

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-09-22 21:02:03 +02:00
Daniel Schwierzeck
b838586086 MIPS: cache: optimise changing of k0 CCA mode
Changing the Cache Coherency Algorithm (CCA) for kernel mode
requires executing from KSEG1. Thus do a jump from KSEG0 to KSEG1
before changing the CCA mode. Jump back to KSEG0 afterwards.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-09-22 21:02:03 +02:00
Daniel Schwierzeck
2f85c2be21 MIPS: cache: reimplement dcache_[status, enable, disable]
Those functions are not needed during cache init and can be
implemented in C. Only support the safe disabling of caches when
this is required for booting an OS. Reenabling caches is much
harder to implement if an optional coherency manager must be
supported. As there is no real use-case anyway, dcache_enable
is implemented with an error message.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-09-22 21:02:03 +02:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Alexey Brodkin
4280342adb fdt: Implement weak arch_fixup_fdt()
Only ARM and in some configs MIPS really implement arch_fixup_fdt().
Others just use the same boilerplate which is not good by itself,
but what's worse if we try to build with disabled CONFIG_CMD_BOOTM
and enabled CONFIG_OF_LIBFDT we'll hit an unknown symbol which was
apparently implemented in arch/xxx/lib/bootm.c.

Now with weak arch_fixup_fdt() right in image-fdt.c where it is
used we get both items highlighted above fixed.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: York Sun <york.sun@nxp.com>
Cc: Stefan Roese <sr@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2018-02-18 12:53:38 -07:00
Paul Burton
cc4f36435f MIPS: Break out of cache loops for unimplemented caches
If we run on a CPU which doesn't implement a particular cache then we
would previously get stuck in an infinite loop, executing a cache op on
the first "line" of the missing cache & then incrementing the address by
0. This was being avoided for the L2 caches, but not for the L1s. Fix
this by generalising the check for a zero line size & avoiding the cache
op loop when this is the case.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: u-boot@lists.denx.de
2017-11-28 21:59:30 +01:00
Paul Burton
d8b326976a MIPS: Clear instruction hazards in flush_cache()
When writing code, for example during relocation, we ensure that the
icache has a coherent view of the new instructions with a call to
flush_cache(). This handles the bulk of the work to ensure the new
instructions will execute as expected, however it does not ensure that
the CPU pipeline doesn't already contain instructions taken from a stale
view of the affected memory. This could theoretically be a problem for
relocation, but in practice typically isn't because we sync caches for
enough code after the entry point of the newly written code that by the
time the CPU pipeline might possibly fetch any of it we'll have long ago
written it back & invalidated any stale icache entries. This is however
a problem for shorter regions of code.

In preparation for later patches which write shorter segments of code,
ensure any instruction hazards are cleared by flush_cache() by
introducing & using a new instruction_hazard_barrier() function which
makes use of the jr.hb instruction to clear the hazard.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: u-boot@lists.denx.de
2017-11-28 21:59:30 +01:00
Paul Burton
219c2db384 MIPS: Ensure cache ops complete in cache maintenance functions
A typical use of cache maintenance functions is to force writeback of
data which a device is about to read using DMA - for example a
descriptor or command structure. Such users of cache maintenance
functions require that operations on the cache have completed before
they proceed to instruct a device to read memory. This requires that we
place a completion barrier (ie. sync instruction) between the cache ops
and whatever write informs the device to perform DMA.

Whilst strictly speaking this isn't all users of the cache maintenance
functions & we could instead place the barriers in the drivers that
require them, it would be much more invasive to do so than to just have
the barrier be the default by placing it in the cache functions
themselves. The cost is low enough that it shouldn't matter to us in any
rare cases that we use the cache functions when not performing DMA.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: u-boot@lists.denx.de
2017-11-28 21:59:30 +01:00
Simon Glass
00caae6d47 env: Rename getenv/_f() to env_get()
We are now using an env_ prefix for environment functions. Rename these
two functions for consistency. Also add function comments in common.h.

Quite a few places use getenv() in a condition context, provoking a
warning from checkpatch. These are fixed up in this patch also.

Suggested-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Simon Glass <sjg@chromium.org>
2017-08-16 08:30:24 -04:00
Zubair Lutfullah Kakakhel
48bfc31b64 MIPS: bootm: Fix broken boot_env_legacy codepath
This patch fixes 2 bugs introduced by the following commit

2bb5b63 MIPS: bootm: rework and fix broken bootm code

The CONFIG_IS_ENABLED macro prepends 'CONFIG_' Hence, remove CONFIG_
from CONFIG_MIPS_BOOT_ENV_LEGACY usage.

Also, 2bb5b63 reworks bootm so that linux_env_legacy runs before
linux_cmdline_legacy. However, linux_env_legacy depends on
linux_cmdline_legacy running first as linux_cmdline_init initialilzes
linux_argp which linux_env_legacy later depends on during its
initialization.

Reorder the code so that linux_cmdline_legacy runs before
linux_env_legacy.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
2017-07-25 20:44:00 +02:00
Paul Burton
703ec9ddf9 MIPS: Stop building position independent code
U-Boot has up until now built with -fpic for the MIPS architecture,
producing position independent code which uses indirection through a
global offset table, making relocation fairly straightforward as it
simply involves patching up GOT entries.

Using -fpic does however have some downsides. The biggest of these is
that generated code is bloated in various ways. For example, function
calls are indirected through the GOT & the t9 register:

  8f998064   lw     t9,-32668(gp)
  0320f809   jalr   t9

Without -fpic the call is simply:

  0f803f01   jal    be00fc04 <puts>

This is more compact & faster (due to the lack of the load & the
dependency the jump has on its result). It is also easier to read &
debug because the disassembly shows what function is being called,
rather than just an offset from gp which would then have to be looked up
in the ELF to discover the target function.

Another disadvantage of -fpic is that each function begins with a
sequence to calculate the value of the gp register, for example:

  3c1c0004   lui    gp,0x4
  279c3384   addiu  gp,gp,13188
  0399e021   addu   gp,gp,t9

Without using -fpic this sequence no longer appears at the start of each
function, reducing code size considerably.

This patch switches U-Boot from building with -fpic to building with
-fno-pic, in order to gain the benefits described above. The cost of
this is an extra step during the build process to extract relocation
data from the ELF & write it into a new .rel section in a compact
format, plus the added complexity of dealing with multiple types of
relocation rather than the single type that applied to the GOT. The
benefit is smaller, cleaner, more debuggable code. The relocate_code()
function is reimplemented in C to handle the new relocation scheme,
which also makes it easier to read & debug.

Taking maltael_defconfig as an example the size of u-boot.bin built
using the Codescape MIPS 2016.05-06 toolchain (gcc 4.9.2, binutils
2.24.90) shrinks from 254KiB to 224KiB.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: u-boot@lists.denx.de
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Tested-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
2017-07-25 20:44:00 +02:00