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* Add GPL-2.0+ SPDX-License-Identifier to source filesWolfgang Denk2013-07-24-6059/+380
| | | | | | Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
* arm:exynos:fix: Fix clock calculation for Exynos4210 based targets.Łukasz Majewski2013-07-16-5/+4
| | | | | | | | | | | Provide proper setting for the APLL fout frequency calculation for Exynos4 based targets (especially Exynos4210 - Trats board). Signed-off-by: Lukasz Majewski <l.majewski@samsung.com> Cc: Minkyu Kang <mk7.kang@samsung.com> Acked-by: Minkyu Kang <mk7.kang@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Tested-by: Simon Glass <sjg@chromium.org>
* Merge branch 'master' of git://git.denx.de/u-boot-armTom Rini2013-07-12-13/+3222
|\ | | | | | | | | | | | | | | | | | | Fix a trivial conflict in arch/arm/dts/exynos5250.dtsi about gpio and serial. Conflicts: arch/arm/dts/exynos5250.dtsi Signed-off-by: Tom Rini <trini@ti.com>
| * Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master'Albert ARIBAUD2013-07-10-9/+3202
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| | * arm: exynos: fix clock calculationMinkyu Kang2013-07-09-5/+38
| | | | | | | | | | | | | | | | | | | | | | | | There are differnce with clock calcuation by cpu variations. This patch will fix it according to user manual. Signed-off-by: Minkyu Kang <mk7.kang@samsung.com> Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
| | * EXYNOS: Move files from board/samsung to arch/armRajeshwari Shinde2013-07-05-4/+3074
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch performs the following: 1) Convert the assembly code for memory and clock initialization to C code. 2) Move the memory and clock init codes from board/samsung to arch/arm 3) Creat a common lowlevel_init file across Exynos4 and Exynos5. Converted the common lowlevel_init from assembly to C-code 4) Made spl_boot.c and tzpc_init.c common for both exynos4 and exynos5. 5) Enable CONFIG_SKIP_LOWLEVEL_INIT as stack pointer initialisation is already done in _main. 6) exynos-uboot-spl.lds made common across SMDKV310, Origen and SMDK5250. TEST: Tested SD-MMC boot on SMDK5250 and Origen. Tested USB and SPI boot on SMDK5250 Compile tested for SMDKV310. Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| | * EXYNOS4210: Configure GPIO for uartRajeshwari Shinde2013-07-05-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch configures the gpio values for UART on Origen and SMDKV310 using pinmux Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| | * EXYNOS: Add API for power reset and exit wakeupRajeshwari Shinde2013-07-05-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | This patch adds APIs to get power reset status and exit the wakeup condition for both exynos5 and exynos4 Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| * | ARM: OMAP: GPIO: Fix valid range and enable usage of all GPIOs on OMAP5Axel Lin2013-07-02-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The omap_gpio driver is used by AM33XX, OMAP3/4, OMAP54XX and DRA7XX SoCs. These SoCs have different gpio count but currently omap_gpio driver uses hard coded 192 which is wrong. This patch fixes this issue by: 1. Move define of OMAP_MAX_GPIO to all arch/arm/include/asm/arch-omap*/gpio.h. 2. Update gpio bank settings and enable GPIO modules 7 & 8 clocks for OMAP5. Thanks for Lubomir Popov to provide valuable comments to fix this issue. Signed-off-by: Axel Lin <axel.lin@ingics.com> Tested-by: Lubomir Popov <lpopov@mm-sol.com> Acked-by: Heiko Schocher <hs@denx.de>
| * | ARM: OMAP4+: Fix MA detection during SDRAM_AUTO_DETECTIONLokesh Vutla2013-07-02-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During SDRAM_AUTO_DETECTION MA is not configured. For Soc's > OMAP4460 MA is present. So populating MA for the same. Tested on OMAP4430 PANDA, OMAP4460 PANDA. Reported-by: Dan Murphy <dmurphy@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
| * | Merge branch 'u-boot-imx/master' into 'u-boot-arm/master'Albert ARIBAUD2013-06-28-0/+10
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| | * | mx27: add i2c clocktrem2013-06-26-0/+2
| | | | | | | | | | | | | | | | | | | | Signed-off-by: Eric Jarrige <eric.jarrige@armadeus.org> Signed-off-by: Philippe Reynes <tremyfr@yahoo.fr>
| | * | mx27: add function enable_cachestrem2013-06-26-0/+8
| | | | | | | | | | | | | | | | Signed-off-by: Philippe Reynes <tremyfr@yahoo.fr>
| * | | pxa: use -mcpu=xscale compiler optionMike Dunn2013-06-22-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass '-mcpu=xscale' to the compiler instead of march and mtune. This will cause gcc to define the __XSCALE__ macro. Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
| * | | pxa: turn icache off in cpu_init_crit()Mike Dunn2013-06-22-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The comment in the low-level initialization function cpu_init_crit() says that the caches are being disabled, but (oddly) the icache is actually turned on. This is probably not a good idea prior to relocating code, so this patch turns it off. Tested on the pxa270. Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
* | | | exynos: Avoid function instrumentation for microsecond timerSimon Glass2013-06-26-1/+1
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | For tracing to work it has to be able to access the microsecond timer without causing a recursive call to the function entry/exit handlers. Add attributes to the relevant functions to support this. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Simon Glass <sjg@chromium.org>
* | | arm: make __rel_dyn_{start, end} compiler-generatedAlbert ARIBAUD2013-06-21-4/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change is only done where needed: some linker scripts may contain relocation symbols yet remain unchanged. __rel_dyn_start and __rel_dyn_end each requires its own output section; putting them in relocation sections changes their flags and breaks relocation. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Tested-by: Lubomir Popov <lpopov@mm-sol.com> Tested-by: Jeroen Hofstee <jeroen@myspectrum.nl> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
* | | arm: make __image_copy_{start, end} compiler-generatedAlbert ARIBAUD2013-06-21-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change is only done where needed: some linker scripts may contain __image_copy_{start,end} yet remain unchanged. Also, __image_copy_end needs its own section; putting it in relocation sections changes their flags and makes relocation break. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Tested-by: Lubomir Popov <lpopov@mm-sol.com> Tested-by: Jeroen Hofstee <jeroen@myspectrum.nl> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
* | | remove all references to .dynsymAlbert ARIBAUD2013-06-21-25/+3
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Discard all .dynsym sections from linker scripts Remove all __dynsym_start definitions from linker scripts Remove all __dynsym_start references from the codebase Note: this touches include/asm-generic/sections.h, which is not ARM-specific, but actual uses of __dynsym_start are only in ARM, so this patch can safely go through the ARM repository. Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net> Tested-by: Lubomir Popov <lpopov@mm-sol.com> Tested-by: Jeroen Hofstee <jeroen@myspectrum.nl> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
* | Merge branch 'u-boot-ti/master' into 'u-boot-arm/master'Albert ARIBAUD2013-06-19-2/+47
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| * | arm, am33xx: move uart soft reset code to common placeHeiko Schocher2013-06-18-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | move uart soft reset code to common place and call this function from board code, instead of copy and paste this code for every board. Signed-off-by: Heiko Schocher <hs@denx.de> Cc: Matt Porter <mporter@ti.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Tom Rini <trini@ti.com> Cc: Enric Balletbo i Serra <eballetbo@iseebcn.com> Acked-by: Tom Rini <trini@ti.com> [trini: Fix igep0033 build, remove 'regval' on pcm051] Signed-off-by: Tom Rini <trini@ti.com>
| * | arm, am335x: make mpu pll config configurableHeiko Schocher2013-06-18-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | upcoming support for siemens boards switches mpu pll clk in board code. So make this configurable. Signed-off-by: Heiko Schocher <hs@denx.de> Cc: Tom Rini <trini@ti.com>
| * | arm, am33xx: move rtc32k_enable() to common placeHeiko Schocher2013-06-18-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | move rtc32k_enable() to common place so all am33xx boards can use it. Signed-off-by: Heiko Schocher <hs@denx.de> Cc: Matt Porter <mporter@ti.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Tom Rini <trini@ti.com> Cc: Enric Balletbo i Serra <eballetbo@iseebcn.com>
* | | Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master'Albert ARIBAUD2013-06-19-7/+64
|\ \ \ | |/ / |/| | | | | | | | Conflicts: spl/Makefile
| * | EXYNOS5: DWMMC: Initialise the local variable to avoid unwanted results.Amar2013-06-13-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch initialises the local variable 'shift' to zero. The uninitialised local variable 'shift' had garbage value and was resulting in unwnated results in the functions exynos5_get_mmc_clk() and exynos4_get_mmc_clk(). Signed-off-by: Amar <amarendra.xt@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Acked-by: Jaehoon Chung <jh80.chung@samsung.com> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| * | exynos: update tzpc to make it common for exynos4 and exynos5Inderpal Singh2013-06-04-7/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This requires that cpu_is_exynos4/5 should be made available before tzpc_init. Hence this patch also makes necessary changes to have cpu_info in spl and invokes arch_cpu_init before tzpc_init in low_level_init.S for smdk5250. Signed-off-by: Inderpal Singh <inderpal.singh@linaro.org> Acked-by: Chander Kashyap <chander.kashyap@linaro.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| * | exynos: move tzpc_init to armv7/exynosInderpal Singh2013-06-04-1/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tzpc_init is common for all exynos5 boards, hence move it to armv7/exynos so that all other boards can use it. Also update the smdk5250 Makefile and config file. Signed-off-by: Inderpal Singh <inderpal.singh@linaro.org> Acked-by: Chander Kashyap <chander.kashyap@linaro.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
| * | Exynos5: clock: Update the equation to calculate PLL output frequencyAkshay Saraswat2013-05-21-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to the latest exynos5 user manual, the equation for calculating PLL output was changed to FOUT= MDIV x FIN/(PDIV x 2^SDIV) earlier it was FOUT= MDIV x FIN/(PDIV x 2^(SDIV -1)) So updating the clock code accordingly. Signed-off-by: Hatim Ali <hatim.rv@samsung.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
* | | arm: pxa: config option for PXA270 turbo modeSergey Yanovich2013-06-12-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | PXA270 CPU has turbo mode. The mode is 2.5 times faster than the default run mode. Activating the mode early significantly speeds up boot process. Signed-off-by: Sergey Yanovich <ynvich@gmail.com>
* | | arm: da830: moved pinmux configurations to the arch treeVishwanathrao Badarkhe, Manish2013-06-10-0/+152
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move pinmux configurations for the DA830 SoCs from board file to the arch tree so that it can be used for all da830 based devices. Also, avoids duplicate pinmuxing in case of NAND. Signed-off-by: Vishwanathrao Badarkhe, Manish <manishv.b@ti.com> Reviewed-by: Tom Rini <trini@ti.com> Acked-by: Christian Riesch <christian.riesch@omicron.at>
* | | OMAP5: Enable access to auxclk registersLubomir Popov2013-06-10-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | auxclk0 and auxclk1 are utilized on some OMAP5 boards. Define the infrastructure needed for accessing them without using magic numbers. Also remove unrelated TPS62361 defines from clocks.h Signed-off-by: Lubomir Popov <lpopov@mm-sol.com>
* | | arm: Remove OMAP2420H4 and all omap24xx supportTom Rini2013-06-10-18/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The omap2420H4 was the only mainline omap24xx board. Prior to being fixed by Jon Hunter in time for v2013.04 it had been functionally broken for a very long time. Remove this board as there's not been interest in it in U-Boot for quite a long time. Signed-off-by: Tom Rini <trini@ti.com>
* | | ARM: DRA7xx: EMIF: Change settings required for EVM boardSricharan R2013-06-10-24/+213
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DRA7 EVM board has the below configuration. Adding the settings for the same here. 2Gb_1_35V_DDR3L part * 2 on EMIF1 2Gb_1_35V_DDR3L part * 4 on EMIF2 Signed-off-by: Sricharan R <r.sricharan@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: DRA7xx: clocks: Update PLL valuesLokesh Vutla2013-06-10-43/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update PLL values. SYS_CLKSEL value for 20MHz is changed to 2. In other platforms SYS_CLKSEL value 2 represents reserved. But in sys_clk array ind 1 is used for 13Mhz. Since other platforms are not using 13Mhz, reusing index 1 for 20MHz. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com> Signed-off-by: Sricharan R <r.sricharan@ti.com>
* | | ARM: DRA7xx: Correct the SYS_CLK to 20MHZSricharan R2013-06-10-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sys_clk on the dra evm board is 20MHZ. Changing the configuration for the same. And also moving V_SCLK, V_OSCK defines to arch/clock.h for OMAP4+ boards. Signed-off-by: Sricharan R <r.sricharan@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: DRA7xx: Do not enable srcomp for DRA7xx Soc'sLokesh Vutla2013-06-10-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | Slew rate compensation cells are not present for DRA7xx Soc's. So return from function srcomp_enable() if soc is not OMAP54xx. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: OMAP5: DRA7xx: support class 0 optimized voltagesNishanth Menon2013-06-10-12/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DRA752 now uses AVS Class 0 voltages which are voltages in efuse. This means that we can now use the optimized voltages which are stored as mV values in efuse and program PMIC accordingly. This allows us to go with higher OPP as needed in the system without the need for implementing complex AVS logic. Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: DRA7xx: clocks: Fixing i2c_init for PMICLokesh Vutla2013-06-10-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | In DRA7xx Soc's voltage scaling is done using GPI2C. So i2c_init should happen before scaling. I2C driver uses __udelay which needs timer to be initialized. So moving timer_init just before voltage scaling. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: DRA7xx: power Add support for tps659038 PMICLokesh Vutla2013-06-10-1/+60
| | | | | | | | | | | | | | | | | | | | | | | | TPS659038 is the power IC used in DRA7XX boards. Adding support for this and also adding pmic data for DRA7XX boards. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: OMAP4+: pmic: Make generic bus init and write functionsLokesh Vutla2013-06-10-6/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Voltage scaling can be done in two ways: -> Using SR I2C -> Using GP I2C In order to support both, have a function pointer in pmic_data so that we can call as per our requirement. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: OMAP2+: Rename asm/arch/clocks.h asm/arch/clock.hLokesh Vutla2013-06-10-6/+6
| | | | | | | | | | | | | | | | | | | | | To be consistent with other ARM platforms, renaming asm/arch-omap*/clocks.h to asm/arch-omap*/clock.h Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: OMAP5: clocks: Do not enable sgx clocksSricharan R2013-06-10-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | SGX clocks should be enabled only for OMAP5 ES1.0. So this can be removed. Signed-off-by: Sricharan R <r.sricharan@ti.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | ARM: OMAP4+: Cleanup header filesLokesh Vutla2013-06-10-0/+5
| | | | | | | | | | | | | | | | | | | | | After having the u-boot clean up series, there are many definitions that are unused in header files. Removing all those unused ones. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
* | | OMAP5: Fix bug in omap5_es1_prcm structLubomir Popov2013-06-10-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The newly introduced function setup_warmreset_time(), called from within prcm_init(), tries to write to the prm_rsttime OMAP5 register. The struct member holding this register's address is however initialized for OMAP5 ES2.0 only. On ES1.0 devices this uninitialized value causes a second (warm) reset at startup. Add .prm_rsttime address init to the ES1.0 struct. Signed-off-by: Lubomir Popov <lpopov@mm-sol.com> Acked-by: Tom Rini <trini@ti.com>
* | | OMAP5: add ABB setup for MPU voltage domainAndrii Tseglytskyi2013-06-10-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | Patch adds a call of abb_setup() function, and proper registers definitions needed for ABB setup sequence. ABB is initialized for MPU voltage domain. Signed-off-by: Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
* | | OMAP3+: introduce generic ABB supportAndrii Tseglytskyi2013-06-10-0/+206
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adaptive Body Biasing (ABB) modulates transistor bias voltages dynamically in order to optimize switching speed versus leakage. Adaptive Body-Bias ldos are present for some voltage domains starting with OMAP3630. There are three modes of operation: * Bypass - the default, it just follows the vdd voltage * Foward Body-Bias - applies voltage bias to increase transistor performance at the cost of power. Used to operate safely at high OPPs. * Reverse Body-Bias - applies voltage bias to decrease leakage and save power. Used to save power at lower OPPs. Signed-off-by: Andrii Tseglytskyi <andrii.tseglytskyi@ti.com> Acked-by: Nishanth Menon <nm@ti.com>
* | | Merge branch 'u-boot-imx/master' into 'u-boot-arm/master'Albert ARIBAUD2013-06-08-3/+491
|\ \ \ | | |/ | |/| | | | | | | Conflicts: drivers/serial/Makefile
| * | arm: mxs: Fix vectoring table craftingMarek Vasut2013-06-03-3/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vectoring table has to be placed at 0x0, but U-Boot on MX23/MX28 starts from RAM, so the vectoring table at 0x0 is not present. Craft code that will be placed at 0x0 and will redirect interrupt vectoring to proper location of the U-Boot in RAM. Signed-off-by: Marek Vasut <marex@denx.de> CC: Stefano Babic <sbabic@denx.de> CC: Fabio Estevam <fabio.estevam@freescale.com> Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
| * | arm: vf610: Add Vybrid VF610 CPU supportAlison Wang2013-06-03-0/+469
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds generic codes to support Freescale's Vybrid VF610 CPU. It aligns Vybrid VF610 platform with i.MX platform. As there are some differences between VF610 and i.MX platforms, the specific codes are in the arch/arm/cpu/armv7/vf610 directory. Signed-off-by: Alison Wang <b18965@freescale.com> Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
* | | ARM: tegra: only enable SCU on Tegra20Tom Warren2013-06-06-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The non-SPL build of U-Boot on Tegra only runs on a single CPU, and hence there is no need to enable the SCU when running U-Boot. If an SMP OS is booted, and it needs the SCU enabled, it will enable the SCU itself. U-Boot doing so is redundant. The one exception is Tegra20, where an enabled SCU is required for some aspects of PCIe to work correctly. Some Tegra SoCs contain CPUs without a software-controlled SCU. In this case, attempting to turn it on actively causes problems. This is the case for Tegra114. For example, when running Linux, the first (or at least some very early) user-space process will trigger the following kernel message: Unhandled fault: imprecise external abort (0x406) at 0x00000000 This is typically accompanied by that process receving a fatal signal, and exiting. Since this process is usually pid 1, this causes total system boot failure. Signed-off-by: Tom Warren <twarren@nvidia.com> [swarren, fleshed out description, ported to upstream chipid APIs] Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Tom Warren <twarren@nvidia.com>