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path: root/arch/arm/cpu/armv7/start.S
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2016-10-06ARM: Introduce function to switch to hypervisor modeKeerthy
On some of the SoCs one cannot enable hypervisor mode directly from the u-boot because the ROM code puts the chip to supervisor mode after it jumps to boot loader. Hence introduce a weak function which can be overridden based on the SoC type and switch to hypervisor mode in a custom way. Cc: beagleboard-x15@googlegroups.com Signed-off-by: Keerthy <j-keerthy@ti.com> Reviewed-by: Tom Rini <trini@konsulko.com>
2016-06-12arm: Allow skipping of low-level init with I-cache onSimon Glass
At present CONFIG_SKIP_LOWLEVEL_INIT prevents U-Boot from calling lowlevel_init(). This means that the instruction cache is not enabled and the board runs very slowly. What is really needed in many cases is to skip the call to lowlevel_init() but still perform CP15 init. Add an option to handle this. Reviewed-by: Heiko Schocher <hs@denx.de> Tested-on: smartweb, corvus, taurus, axm Tested-by: Heiko Schocher <hs@denx.de> Reviewed-by: Joe Hershberger <joe.hershberger@ni.com> Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Andreas Bießmann <andreas@biessmann.org>
2015-08-12ARM: Introduce erratum workaround for 801819Nishanth Menon
Add workaround for Cortex-A15 ARM erratum 801819 which says in summary that "A livelock can occur in the L2 cache arbitration that might prevent a snoop from completing. Under certain conditions this can cause the system to deadlock. " Recommended workaround is as follows: Do both of the following: 1) Do not use the write-back no-allocate memory type. 2) Do not issue write-back cacheable stores at any time when the cache is disabled (SCTLR.C=0) and the MMU is enabled (SCTLR.M=1). Because it is implementation defined whether cacheable stores update the cache when the cache is disabled it is not expected that any portable code will execute cacheable stores when the cache is disabled. For implementations of Cortex-A15 configured without the “L2 arbitration register slice” option (typically one or two core systems), you must also do the following: 3) Disable write-streaming in each CPU by setting ACTLR[28:25] = 0b1111 So, we provide an option to disable write streaming on OMAP5 and DRA7. It is a rare condition to occur and may be enabled selectively based on platform acceptance of risk. Applies to: A15 revisions r2p0, r2p1, r2p2, r2p3 or r2p4 and REVIDR[3] is set to 0. Note: certain unicore SoCs *might* not have REVIDR[3] not set, but might not meet the condition for the erratum to occur when they donot have ACP (Accelerator Coherency Port) hooked to ACE (AXI Coherency Extensions). Such SoCs will need the work around handled in the SoC specific manner, since there is no ARM generic manner to detect such configurations. Based on ARM errata Document revision 18.0 (22 Nov 2013) Suggested-by: Richard Woodruff <r-woodruff2@ti.com> Suggested-by: Brad Griffis <bgriffis@ti.com> Reviewed-by: Brad Griffis <bgriffis@ti.com> Signed-off-by: Nishanth Menon <nm@ti.com>
2015-07-07armv7: better comment in start.SPavel Machek
Fix big/small letters in comment. Signed-off-by: Pavel Machek <pavel@denx.de> Tested-by: Marek Vasut <marex@denx.de>
2015-03-24remove unnecessary version.h includesRob Herring
Various files are needlessly rebuilt every time due to the version and build time changing. As version.h is not actually needed, remove the include. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Stefano Babic <sbabic@denx.de> Cc: Minkyu Kang <mk7.kang@samsung.com> Cc: Marek Vasut <marex@denx.de> Cc: Tom Warren <twarren@nvidia.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Macpaul Lin <macpaul@andestech.com> Cc: Wolfgang Denk <wd@denx.de> Cc: York Sun <yorksun@freescale.com> Cc: Stefan Roese <sr@denx.de> Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org> Cc: Simon Glass <sjg@chromium.org> Cc: Philippe Reynes <tremyfr@yahoo.fr> Cc: Eric Jarrige <eric.jarrige@armadeus.org> Cc: "David Müller" <d.mueller@elsoft.ch> Cc: Phil Edworthy <phil.edworthy@renesas.com> Cc: Robert Baldyga <r.baldyga@samsung.com> Cc: Torsten Koschorrek <koschorrek@synertronixx.de> Cc: Anatolij Gustschin <agust@denx.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Łukasz Majewski <l.majewski@samsung.com>
2015-03-13ARM: Introduce erratum workaround for 621766Nishanth Menon
621766: Under a specific set of conditions, executing a sequence of NEON or vfp load instructions can cause processor deadlock Impacts: Every Cortex-A8 processors with revision lower than r2p1 Work around: Set L1NEON to 1 Based on ARM errata Document revision 20.0 (13 Nov 2010) Signed-off-by: Nishanth Menon <nm@ti.com> Tested-by: Matt Porter <mporter@konsulko.com> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-03-13ARM: Introduce erratum workaround for 430973Nishanth Menon
430973: Stale prediction on replaced inter working branch causes Cortex-A8 to execute in the wrong ARM/Thumb state Impacts: Every Cortex-A8 processors with revision lower than r2p1 Work around: Set IBE to 1 Based on ARM errata Document revision 20.0 (13 Nov 2010) Signed-off-by: Nishanth Menon <nm@ti.com> Tested-by: Matt Porter <mporter@konsulko.com> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-03-13ARM: Introduce erratum workaround for 454179Nishanth Menon
454179: Stale prediction may inhibit target address misprediction on next predicted taken branch Impacts: Every Cortex-A8 processors with revision lower than r2p1 Work around: Set IBE and disable branch size mispredict to 1 Also provide a hook for SoC specific handling to take place if needed. Based on ARM errata Document revision 20.0 (13 Nov 2010) Signed-off-by: Nishanth Menon <nm@ti.com> Tested-by: Matt Porter <mporter@konsulko.com> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-03-13ARM: Introduce erratum workaround for 798870Nishanth Menon
Add workaround for Cortex-A15 ARM erratum 798870 which says "If back-to-back speculative cache line fills (fill A and fill B) are issued from the L1 data cache of a CPU to the L2 cache, the second request (fill B) is then cancelled, and the second request would have detected a hazard against a recent write or eviction (write B) to the same cache line as fill B then the L2 logic might deadlock." Implementations for SoC families such as Exynos, OMAP5/DRA7 etc will be widely different. Every SoC has slightly different manner of setting up access to L2ACLR and similar registers since the Secure Monitor handling of Secure Monitor Call(smc) is diverse. Hence an weak function is introduced which may be overriden to implement SoC specific accessor implementation. Based on ARM errata Document revision 18.0 (22 Nov 2013) Signed-off-by: Nishanth Menon <nm@ti.com> Tested-by: Matt Porter <mporter@konsulko.com> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-02-16sunxi: Support the FEL boot mode in the regular u-boot buildSiarhei Siamashka
So that the CONFIG_SPL_FEL option is not needed anymore. And the regular SPL binary, generated by the default u-boot build, is now also bootable over USB in the FEL mode. The SPL still can boot from the SD card too. A bunch of system registers need to be saved/restored in order to ensure that the IRQ handler still works in the BROM FEL code after getting control back from the SPL. This is done in the sunxi code instead of abusing ifdefs in 'start.S'. The decision whether to load the main u-boot binary from the SD card or return to the FEL code in the BROM is done at runtime. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> [hdegoede@redhat.com: Since we now restore various regs before returning to the FEL BROM code we can drop the sunxi specific #ifdefs in start.S] Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-02-16sunxi: Normalise FEL supportSimon Glass
Make sunxi's FEL code fit with the normal U-Boot boot sequence instead of creating its own. There are some #ifdefs required in start.S. Future work will hopefully remove these. This series is available at u-boot-dm, branch sunxi-working. Signed-off-by: Simon Glass <sjg@chromium.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-02-16arm: Allow lr to be saved by board codeSimon Glass
The link register value can be required on some boards (e.g. FEL mode on sunxi) so use a branch instruction to jump to save_boot_params() instead of a branch link. This requires a branch back to save_boot_params_ret so adjust the users to deal with this. For exynos just drop the function since it doesn't do anything. Signed-off-by: Simon Glass <sjg@chromium.org> Acked-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-01-30ARM: armv7 fix spelling of SCTRLPeng Fan
SCTLR is the abbreviation of System Control Register, so we should use SCTLR but not SCTRL. Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
2014-10-29arm: relocate the exception vectorsGeorges Savoundararadj
This commit relocates the exception vectors. As ARM1176 and ARMv7 have the security extensions, it uses VBAR. For the other ARM processors, it copies the relocated exception vectors to the correct address: 0x00000000 or 0xFFFF0000. Signed-off-by: Georges Savoundararadj <savoundg@gmail.com> Acked-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Cc: Tom Warren <twarren@nvidia.com>
2014-05-15arm: move exception handling out of start.S filesAlbert ARIBAUD
Exception handling is basically identical for all ARM targets. Factorize it out of the various start.S files and into a single vectors.S file, and adjust linker scripts accordingly. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-05-15arm: remove unused _end_vect and _vectors_end symbolsAlbert ARIBAUD
Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-04-07ARM: Add workaround for Cortex-A9 errata 761320Nitin Garg
Full cache line writes to the same memory region from at least two processors might deadlock the processor. Exists on r1, r2, r3 revisions. Signed-off-by: Nitin Garg <nitin.garg@freescale.com> Acked-by: Fabio Estevam <fabio.estevam@freescale.com>
2014-04-07ARM: Add workaround for Cortex-A9 errata 794072Nitin Garg
A short loop including a DMB instruction might cause a denial of service on another processor which executes a CP15 broadcast operation. Exists on r1, r2, r3, r4 revisions. Signed-off-by: Nitin Garg <nitin.garg@freescale.com> Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
2014-02-26arm: remove unneeded symbol offsets and _TEXT_BASEAlbert ARIBAUD
Remove the last uses of symbol offsets in ARM U-Boot. Remove some needless uses of _TEXT_BASE. Remove all _TEXT_BASE definitions. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-01-26ARM: armv7: Make indirect vector addresses globlMarek Vasut
Make indirect vectors addresses global, so they can be replaced by various code that needs to do so. For example the MX6 PCI express driver needs to temporarily replace data abort handler when reading the config space. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Eric Nelson <eric.nelson@boundarydevices.com> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Stefano Babic <sbabic@denx.de>
2013-10-14Coding Style cleanup: remove trailing white spaceWolfgang Denk
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-07-24Add GPL-2.0+ SPDX-License-Identifier to source filesWolfgang Denk
Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
2013-05-30arm: factorize relocate_code routineAlbert ARIBAUD
Replace all relocate_code routines from ARM start.S files with a single instance in file arch/arm/lib/relocate.S. For PXA, this requires moving the dcache unlocking code from within relocate_code into c_runtime_cpu_setup. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Tested-by: Simon Glass <sjg@chromium.org>
2013-05-30arm: do not compile relocate_code() for SPL buildsAlbert ARIBAUD
Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Tested-by: Simon Glass <sjg@chromium.org>
2013-04-15Tegra: Restore cp15 VBAR _start vector write for ARMv7Tom Warren
A start vector fix was added by AneeshV for OMAP4 (commit 0d479b53), and caused the old monilithic Tegra builds to hang due to an undefined instruction trap. Previously, the code needed to run on both the AVP (ARM7TDI) and A9, and the AVP doesn't have a CP15 register. I corrected this in commit 6d6c0bae w/#ifndef CONFIG_TEGRA, but now that we use SPL, and boot the AVP w/o any ARMv7 code, I can revert my change, and make Aneesh's change apply to Tegra. Signed-off-by: Tom Warren <twarren@nvidia.com>
2013-04-15ARMv7: start.S: stay in HYP mode if u-boot is entered in itAndre Przywara
The KVM and Xen hypervisors for the Cortex-A15 virtualization implementation need to be entered in HYP mode. Should the primary board firmware already enter HYP mode (Calxeda firmware does that), we should not deliberately drop back to SVC mode. Since U-boot does not use the MMU, running in HYP mode is just fine. Signed-off-by: Andre Przywara <andre.przywara@linaro.org>
2013-04-13BUGFIX: arm: data abort in get_bad_stack_swiTetsuyuki Kobayashi
When swi instruction is executed, it is expected to get message "software interrupt" in console and dump registers and reboot, as do_software_interrupt() in arch/arm/lib/interrupts.c. But, actually it causes data abort accessing wrong address in get_bad_stack_swi macro in arch/arm/cpu/v7/start.S. This patch fixes this problem. The same mistake in arch/arm/cpu/{arm1136,arm1176,pxa}/start.S. Signed-off-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
2013-04-12arm: Remove unused relocate_code() parametersBenoît Thébaudeau
Commit e05e5de7fae5bec79617e113916dac6631251156 made the 2 1st parameters of ARM's relocate_code() useless since it moved the code handling them to crt0.S. So, drop these parameters. Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-04-12arm: relocate_code(): Use __image_copy_end for end of relocationBenoît Thébaudeau
Use __image_copy_end instead of __bss_start for the end of the image to relocate. This is the same as commit 033ca72, but applied to all ARM start.S. This is a more appropriate symbol naming for an image copy & relocate feature, and this also saves a useless copy of data put between __image_copy_end and __bss_start in linker scripts (e.g. relocation information, or MMU initialization tables used only before jumping to the relocated image). Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-04-12arm: relocate_code(): Remove useless relocation offset computationBenoît Thébaudeau
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-04-12arm: relocate_code() is no longer noreturnBenoît Thébaudeau
Commit e05e5de7fae5bec79617e113916dac6631251156 made ARM's relocate_code() return to its caller, but it did not update its declaration accordingly. Fixing this function declaration fixes dropped C code following calls to relocate_code(). Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-04-12arm: start.S: Fix _TEXT_BASE for SPLBenoît Thébaudeau
_TEXT_BASE must be set to CONFIG_SPL_TEXT_BASE for generic SPL, and to CONFIG_SYS_TEXT_BASE for non-SPL builds. Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Reviewed-by: Tom Rini <trini@ti.com>
2013-03-28armv7: do not relocate _start twiceVincent Stehlé
The _start symbol is already relocated, so do not add the relocation the second time in c_runtime_cpu_setup. This fixes e.g. the abort exception handling path, which ended in double fault due to bad address in VBAR. Signed-off-by: Vincent Stehlé <v-stehle@ti.com> Reported-by: Lubomir Popov <lpopov@mm-sol.com>
2013-03-22ARM: implement erratum 716044 workaroundStephen Warren
Add common code to enable the workaround for ARM erratum 716044. This will be enabled for Tegra. Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-03-18Merge branch 'master' of git://git.denx.de/u-boot-armTom Rini
Albert's rework of the linker scripts conflicted with Simon's making everyone use __bss_end. We also had a minor conflict over README.scrapyard being added to in mainline and enhanced in u-boot-arm/master with proper formatting. Conflicts: arch/arm/cpu/ixp/u-boot.lds arch/arm/cpu/u-boot.lds arch/arm/lib/Makefile board/actux1/u-boot.lds board/actux2/u-boot.lds board/actux3/u-boot.lds board/dvlhost/u-boot.lds board/freescale/mx31ads/u-boot.lds doc/README.scrapyard include/configs/tegra-common.h Build tested for all of ARM and run-time tested on am335x_evm. Signed-off-by: Tom Rini <trini@ti.com>
2013-03-15Replace __bss_end__ with __bss_endSimon Glass
Note this is a tree-wide change affecting multiple architectures. At present we use __bss_start, but mostly __bss_end__. This seems inconsistent and in a number of places __bss_end is used instead. Change to use __bss_end for the BSS end symbol throughout U-Boot. This makes it possible to use the asm-generic/sections.h file on all archs. Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-13ARM: implement some Cortex-A9 errata workaroundsStephen Warren
Various errata exist in the Cortex-A9 CPU, and may be worked around by setting some bits in a CP15 diagnostic register. Add code to implement the workarounds, enabled by new CONFIG_ options. This code was taken from the Linux kernel, v3.8, arch/arm/mm/proc-v7.S, and modified to remove the logic to conditionally apply the WAR (since we know exactly which CPU we're running on given the U-Boot configuration), and use r0 instead of r10 for consistency with the rest of U-Boot's cpu_init_cp15(). Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Simon Glass <sjg@chromium.org>
2013-01-16Tegra30: Add generic Tegra30 build supportTom Warren
This patch adds basic Tegra30 (T30) build support - no specific board is targeted. Signed-off-by: Tom Warren <twarren@nvidia.com> Reviewed-by: Stephen Warren <swarren@nvidia.com>
2013-01-08arm: move C runtime setup code in crt0.SAlbert ARIBAUD
Move all the C runtime setup code from every start.S in arch/arm into arch/arm/lib/crt0.S. This covers the code sequence from setting up the initial stack to calling into board_init_r(). Also, rewrite the C runtime setup and make functions board_init_*() and relocate_code() behave according to normal C semantics (no jumping across the C stack any more, etc). Some SPL targets had to be touched because they use start.S explicitly or for some reason; the relevant maintainers and custodians are cc:ed. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2012-10-04armv7 cpu_init_crit: Simplify codeBenoît Thébaudeau
We don't need to return to cpu_init_crit after calling lowlevel_init, so lowlevel_init can directly return to the caller of cpu_init_crit. Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Cc: Albert Aribaud <albert.u.boot@aribaud.net>
2012-09-27SPL: Create arch/arm/lib/spl.c for board_init_f and jump_to_image_linuxTom Rini
In SPL (CONFIG_SPL_FRAMEWORK) board_init_f must setup the stack pointer, clear the BSS and call board_init_r. We mark this as weak as some platforms may need to perform additional initalization at this point. We provide a gd that we know will be in a usable location, once the BSS has been cleared to help with this as well. Finally, we no longer call relocate_code so remove that from the armv7 version. Next, both board_init_f and jump_to_image_linux are going to be inherently arch-specific, so move these versions to arch/arm/lib/spl.c Signed-off-by: Tom Rini <trini@ti.com>
2012-09-01arm: bugfix: save_boot_params_default accesses uninitalized stack when -O0Tetsuyuki Kobayashi
save_boot_params_default() in cpu.c accesses uninitialized stack area when it compiled with -O0 (not optimized). This patch removes save_boot_params_default() and put the equivalent in start.S Signed-off-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp> Acked-by: Tom Rini <trini@ti.com>
2012-09-01tegra20: enable SPL for tegra20 boardsAllen Martin
Add SPL options to tegra20 config files and enable SPL build for tegra20 boards. Also remove redundant code from u-boot that is not contained in SPL. Signed-off-by: Allen Martin <amartin@nvidia.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Tested-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-09-01tegra20: rename tegra2 -> tegra20Allen Martin
This is make naming consistent with the kernel and devicetree and in preparation of pulling out the common tegra20 code. Signed-off-by: Allen Martin <amartin@nvidia.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Tested-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-07-20arm: Fix to mistake clean the memory spaceZhong Hongbo
In currently, when __bss_start is equal to __bss_end__, The bss loop will clear all the things in memory space. But just only when __bss_end__ greater than __bss_start__, we do the clear bss section operation. Signed-off-by: Zhong Hongbo <bocui107@gmail.com> Acked-by: Andreas Bießmann <andreas.devel@googlemail.com>
2012-07-07arm: bugfix: Move vector table before jumping relocated codeTetsuyuki Kobayashi
Interrupts and exceptions doesn't work in relocated code. It badly use IRQ_STACK_START_IN in rom area as interrupt stack. It is because the vecotr table is not moved to ram area. This patch moves vector table before jumping relocated code. Signed-off-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp> Tested-by: Tom Rini <trini@ti.com>
2012-05-15armv7: add appropriate headers for assembly functionsAneesh V
Use ENTRY and ENDPROC with assembly functions to ensure necessary assembler directives for all functions. Signed-off-by: Aneesh V <aneesh@ti.com> Acked-by: Mike Frysinger <vapier@gentoo.org>
2011-12-21arm: Tegra: fix undefined instruction hang immediately after resetTom Warren
commit 0d479b53 (Aneesh V) added code for OMAP4 that doesn't execute on Tegra, due to the AVP (ARM7TDI) not having a CP15. Result was an undefined instruction hang just after reset. Signed-off-by: Tom Warren <twarren@nvidia.com> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Tom Rini <trini@ti.com> Acked-by: Aneesh V <aneesh@ti.com>
2011-12-09tegra2: Remove unneeded boot codeSimon Glass
Since we have cache support built in we can remove Tegra's existing cache initialization code amd other related dead code. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>
2011-12-09arm: Move CP15 init out of cpu_init_crit()Simon Glass
Some SOCs have do not start up with their 'main' CPU. The first U-Boot code may then be executed with a CPU which does not have a CP15, or not a useful one. Here we split the initialization of CP15 into a separate call, which can be performed later if required. Once the main CPU is running, you should call cpu_init_cp15() to perform this init as early as possible. Existing ARMv7 boards which define CONFIG_SKIP_LOWLEVEL_INIT should not need to change, this CP15 init is still skipped in that case. The only impact for these boards is that the cpu_init_cp15() will be available even if it is never used on these boards. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Tom Warren <twarren@nvidia.com>