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2017-06-12sunxi: psci: Move entry address setting to separate functionChen-Yu Tsai
Currently we set the entry address in the psci_cpu_on function. However R40 has a different register for this. This resulted in an #ifdef / #else block in psci_cpu_on, which we avoided having in the first place. Move this part into a separate function, defined differently for the R40 as opposed to the other single cluster platforms. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
2017-04-20sunxi: Add PSCI support for R40Chen-Yu Tsai
The R40's CPU controls are a combination of sun6i and sun7i. All controls are in the CPUCFG block, and it seems the R40 does not have a PRCM block. The core reset, power gating and clamp controls are grouped like sun6i. Last, the R40 does not have a secure SRAM block. This patch adds a PSCI implementation for CPU bring-up and hotplug for the R40. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2017-04-05ARM: rename CONFIG_TIMER_CLK_FREQ to COUNTER_FREQUENCYAndre Przywara
Many ARMv8 boards define a constant COUNTER_FREQUENCY to specify the frequency of the ARM Generic Timer (aka. arch timer). ARMv7 boards traditionally used CONFIG_TIMER_CLK_FREQ for the same purpose. It seems useful to unify them. Since there are less occurences of the latter version, lets convert all users over to COUNTER_FREQUENCY. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Jagan Teki <jagan@openedev.com>
2016-08-05ARM: Rework and correct barrier definitionsTom Rini
As part of testing booting Linux kernels on Rockchip devices, it was discovered by Ziyuan Xu and Sandy Patterson that we had multiple and for some cases incomplete isb definitions. This was causing a failure to boot of the Linux kernel. In order to solve this problem as well as cover any corner cases that we may also have had a number of changes are made in order to consolidate things. First, <asm/barriers.h> now becomes the source of isb/dsb/dmb definitions. This however introduces another complexity. Due to needing to build SPL for 32bit tegra with -march=armv4 we need to borrow the __LINUX_ARM_ARCH__ logic from the Linux Kernel in a more complete form. Move this from arch/arm/lib/Makefile to arch/arm/Makefile and add a comment about it. Now that we can always know what the target CPU is capable off we can get always do the correct thing for the barrier. The final part of this is that need to be consistent everywhere and call isb()/dsb()/dmb() and NOT call ISB/DSB/DMB in some cases and the function names in others. Reviewed-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Acked-by: Ziyuan Xu <xzy.xu@rock-chips.com> Acked-by: Sandy Patterson <apatterson@sightlogix.com> Reported-by: Ziyuan Xu <xzy.xu@rock-chips.com> Reported-by: Sandy Patterson <apatterson@sightlogix.com> Signed-off-by: Tom Rini <trini@konsulko.com>
2016-07-15ARM: PSCI: Switch to per-CPU target PC storage in secure data sectionChen-Yu Tsai
Now that we have a secure data section and space to store per-CPU target PC address, switch to it instead of storing the target PC on the stack. Also save clobbered r4-r7 registers on the stack and restore them on return in psci_cpu_on for Tegra, i.MX7, and LS102xA platforms. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-07-15ARM: Move __secure definition to common asm/secure.hChen-Yu Tsai
sunxi and i.mx7 both define the __secure modifier to put functions in the secure section. Move this to a common place. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-07-15ARM: PSCI: Remove unused psci_text_end symbolChen-Yu Tsai
psci_text_end was used to calculate the PSCI stack address following the secure monitor text. Now that we have an explicit secure stack section, this is no longer used. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-07-15sunxi: Move remaining PSCI assembly code to CChen-Yu Tsai
This patch finishes the rewrite of sunxi specific PSCI parts into C code. The assembly-only stack setup code has been factored out into a common function for ARMv7. The GIC setup code can be renamed as psci_arch_init. And we can use an empty stub function for psci_text_end. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-07-15ARM: PSCI: Split out common stack setup code from psci_arch_initChen-Yu Tsai
Every platform has the same stack setup code in assembly as part of psci_arch_init. Move this out into a common separate function, psci_stack_setup, for all platforms. This will allow us to move the remaining parts of psci_arch_init into C code, or drop it entirely. Also provide a stub no-op psci_arch_init for platforms that don't need their own specific setup code. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-06-20sunxi: Add PSCI implementation in CChen-Yu Tsai
To make the PSCI backend more maintainable and easier to port to newer SoCs, rewrite the current PSCI implementation in C. Some inline assembly bits are required to access coprocessor registers. PSCI stack setup is the only part left completely in assembly. In theory this part could be split out of psci_arch_init into a separate common function, and psci_arch_init could be completely in C. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-06-20sunxi: Add base address for GICChen-Yu Tsai
Instead of hardcoding the GIC addresses in the PSCI implementation, provide a base address in the cpu header. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-06-20sunxi: Make CPUCFG_BASE macro names the same across familiesChen-Yu Tsai
Use SUNXI_CPUCFG_BASE across all families. This makes writing common PSCI code easier. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-04-01sunxi: Move cpu independent code to mach directoryAlexander Graf
Some of the code in arch/arm/cpu/armv7/sunxi is actually armv7 specific, while most of it is just generic code that could as well be used on an AArch64 SoC. Move all files that are not really tied to armv7 into a new mach-sunxi directory. Signed-off-by: Alexander Graf <agraf@suse.de> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-03-31sunxi: usb_phy: Add support for A83T USB PHYsChen-Yu Tsai
The A83T has 3 USB PHYs: 1 for USB OTG, 1 for standard USB 1.1/2.0 host, 1 for USB HSIC. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-03-31sunxi: Print soc-id from sram controller for sun8i boardsHans de Goede
As the need for various magic sram pokes has shown this maybe useful info to have. e.g. this shows one of my a23 tablets having an id of 1661 rather then the usual 1650 for the a23. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-31sunxi: Add conditional magic sram poke for A33Hans de Goede
I noticed that for certain SoC versions boot0 does a magic poke when build for A33. I'm not aware of this actually being necessary anywhere, but better safe then sorry. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-23sunxi: A83T: fix 32bit overflow warningvishnupatekar
In mctl_channel_init, (0x50<<26) which overflows 32bit. It was supposed to be 0x50<<16,corrected now. Reported-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-03-23sunxi: Fix gmac not working due to cpu_eth_init no longer being calledHans de Goede
cpu_eth_init is no longer called for dm enabled eth drivers, this was causing the sunxi gmac eth controller to no longer work in u-boot. This commit fixes this by calling the clock, reset and pinmux setup function from s_init() and enabling the phy power pin (if any) from board_init(). The enabling of phy power cannot be done from s_init because it uses dm and dm is not ready yet at this point. Note that the mdelay is dropped as the phy gets enabled much earlier now, so it is no longer needed. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Tested-by: Karsten Merker <merker@debian.org> Tested-by: Michael Haas <haas@computerlinguist.org>
2016-03-23sunxi: Add support for USB vbus pin for USB3Hans de Goede
The H3 has USB0 - USB3, add support for having a USB vbus pin for USB3. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-23sunxi: Fix clock_twi_onoff for sun9iHans de Goede
Fix a copy and paste error which caused us to use the uart rather then the twi reset bits in clock_twi_onoff for sun9i. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-23sunxi: Fix clock_twi_onoff for sun8i-a83Hans de Goede
clock_sun8i_a83.c did not contain a clock_twi_onoff implementation at all, this is fixed by moving the clock_sun6i.c implementation, which is correct for the a83 too, to a shared location. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-23sunxi: Fix clock_twi_onoff for sun6iHans de Goede
The clock_sun6i.c implementation was not deasserting the reset for the regular i2c controllers, this commit fixes this. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-03-23sunxi: A23: Fix some revisions needing a different magic sram pokeHans de Goede
I've had this one a23 tablet which would not boot and I've finally figured out what the problem is by looking at the released boot0 code, it seems the magic sram controller poke which we need to do in s_init() depends on the revision of the a23. Specifically this change is needed to get the A23 SoC I have with the following serial to boot: "E6071AB 26Y7". Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2016-02-23sunxi: H3: Add support for the host usb-physJelle van der Waa
Add support for phy 1-3. Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl> [hdegoede@redhat.com: use setclrbits_le32 instead of read-modify-write] Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Add support for LPDDR3 for A83TVishnu Patekar
Banana-pi M3 has LPDDR3 DRAM. this adds support for LPDDR3 for A83T. Mostly the timing parameters are different from DDR3. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Groundwork to support new dram type for A83TVishnu Patekar
Different A83T boards have different DRAM types. Banapi M3 has LPDDR3, Allwinner Homlet v1.2 has DDR3. This adds groundwork to support for new DRAM type for A83T. Introduce CONFIG_DRAM_TYPE, It'll be 3 for DDR3 and 7 for LPDDR3, must be set in respective board defconfig. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Redundant code cleanup from a83t dram initVishnu Patekar
This removes the redundant lines of code from mctl_sys_init. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Support PSCI ops on Allwinner H3Chen-Yu Tsai
H3 has the same power sequencing procedure as the A31/A31s, which includes the power clamps. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Support H3 CCU security switchesChen-Yu Tsai
H3's CCU includes some switches which disable non-secure access to some of the more critical clock controls, such as MBUS, PLLs, and main platform busses. Configure them to enable non-secure access. For now the only SoC that has this feature is the H3. For other platforms just use a default (weak) empty function so things do not break. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-26sunxi: Support Secure Memory Touch Arbiter (SMTA) in sun8i H3Chen-Yu Tsai
Secure Memory Touch Arbiter is the same thing as the TrustZone Protection Controller found on A31/A31s. Access to many peripherals on the H3 can be controlled by the SMTA, and the settings default to secure access only. This patch supports the new settings, and sets them to allow non-secure access. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2016-01-21sunxi: Add support for the I2C controller which is part of the PRCMJelle van der Waa
Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl> [hdegoede@redhat.com: Minor cleanups] Signed-off-by: Hans de Goede <hdegoede@redhat.com> applied with fixing 2 checkpatch warnings: WARNING: please, no space before tabs Signed-off-by: Heiko Schocher <hs@denx.de>
2015-12-10sunxi: Fix H3 DRAM DQ read delay configurationJens Kuske
The read delays were set incorrectly, leading to reliability issues at higher DRAM clock speeds. This commit adjusts this to match the vendor boot0 behaviour. Signed-off-by: Jens Kuske <jenskuske@gmail.com> Tested-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sun4i: clock: Cleanup some whitespace errorsOlliver Schinagl
Add some spaces around operators. Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: twi: Enable clocks on sun7iOlliver Schinagl
Commit 6c739c5d added code to enable i2c bus 4 and 5 on the sun7i SoC but forgot to extend the range check in clock_twi_onoff, resulting in the clock not getting enabled. The range-check is not needed at all, since clock_twi_onoff only gets called with such high indexes when CONFIG_I2C3_ENABLE / CONFIG_I2C4_ENABLE is set and Kconfig already only allows these on sun6i / sun7i. This commit removes the range-check all together fixing i2c bus 4 and 5 not working on sun7i. Signed-off-by: Olliver Schinagl <o.schinagl@ultimaker.com> [hdegoede@redhat.com] Remove range check instead of extending it Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: Add support for Allwinner A83T DRAMvishnupatekar
Add support for A83T dram. Register are different from sun8i A33. init code is similar to A33 dram init. hope we'll shift duplicate code in dram_sun8i_* to dram helper in future. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: clk: add basic clocks for A83Tvishnupatekar
Add basic clocks pll1, pll5, and some default values from allwinner u-boot. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> [hdegoede@redhat.com] Fix PLL6 init to run at 600 MHz instead of 288 MHz, fixing the mmc support not working [hdegoede@redhat.com] Fix PLL init code to properly wait for the PLL-s to stabilize, fixing cold-booting directly from sdcard not working Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: power: enabled support for axp818vishnupatekar
Enabled support for AXP818 in SPL and u-boot. DCDC1, DCDC2, DCDC3 and DCSC5 are enabled. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: Add support for UART0 in PB pin group on A83Tvishnupatekar
On A83T, PB9,PB10 are UART0 pins. On allwinner A83T Dev board(h8homlet), this uart0 serial connector is exposed. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-12-10sunxi: Add Machine Support for A83T SOCvishnupatekar
Allwinner A83T is octa-core cortex-a7 SOC. This enables support for A83T. SMP is not yet supported. Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-11-22sunxi: clock: Set AHB1 clock frequency to 200MHz on Allwinner H3Siarhei Siamashka
The 3.4 kernel from the Allwinner SDK is clocking AHB1 at 200MHz on Allwinner H3 and using PLL6 as the clock source (PLL6/3). This can be verified by reading the value of the AHB1_APB1_CFG_REG register via /dev/mem. It always reads as 0x3180 regardless of the current cpufreq operating point. So this configuration should be safe for use in U-Boot too. PLL6 also needs to be configured before it is used as the clock source, according to the "CCU / Programming Guidelines" section of the Allwinner manual. The current low AHB1 clock speed is limiting the USB transfer speed when booting via FEL. This patch can increase the FEL USB transfer speed from ~510 KB/s to ~950 KB/s. Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-11-22sunxi: Add H3 DRAM initialization supportJens Kuske
Based on existing A23/A33 code and the original H3 boot0. Signed-off-by: Jens Kuske <jenskuske@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-11-22sunxi: Add basic H3 supportJens Kuske
Add initial sun8i H3 support, only uart + mmc are supported for now. Signed-off-by: Jens Kuske <jenskuske@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-11-18spl: mmc: add support for BOOT_DEVICE_MMC2Nikita Kiryanov
Currently the mmc device that SPL looks at is always mmc0, regardless of the BOOT_DEVICE_MMCx value. This forces some boards to implement hacks in order to boot from other mmc devices. Make SPL take into account the correct mmc device. Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-11-18spl: change return values of spl_*_load_image()Nikita Kiryanov
Make spl_*_load_image() functions return a value instead of hanging if a problem is encountered. This enables main spl code to make the decision whether to hang or not, thus preparing it to support alternative boot devices. Some boot devices (namely nand and spi) do not hang on error. Instead, they return normally and SPL proceeds to boot the contents of the load address. This is considered a bug and is rectified by hanging on error for these devices as well. Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il> Cc: Igor Grinberg <grinberg@compulab.co.il> Cc: Tom Rini <trini@konsulko.com> Cc: Simon Glass <sjg@chromium.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Hans De Goede <hdegoede@redhat.com> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: Jagan Teki <jteki@openedev.com> Reviewed-by: Tom Rini <trini@konsulko.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2015-10-20sunxi: board: Only try to use the MMC related functions if enabledMaxime Ripard
So far, even if CONFIG_MMC was not enabled the board code was trying to use the MMC-related functions, resulting in linker errors. Protect those calls by an ifdef. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-10-20sunxi: power: Unify axp pmic function namesHans de Goede
Stop prefixing the axp functions for setting voltages, etc. with the model number, there ever is only one pmic driver built into u-boot, this allows simplifying the callers. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2015-10-20sunxi: Switch to using malloc_simple for the splHans de Goede
common/dlmalloc.c is quite big, both in .text and .data usage. E.g. for a Mele_M9 sun6i board build this reduces .text from 0x4214 to 0x3b94 bytes, and .data from 0x54c to 0x144 bytes. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk> Reviewed-by: Tom Rini <trini@konsulko.com>
2015-09-29sunxi: retrieve FEL-provided values to environment variablesBernhard Nortmann
This patch extends the misc_init_r() function on sunxi boards to test for the presence of a suitable "sunxi" SPL header. If found, and the loader ("fel" utility) provided a non-zero value for the boot.scr address, then the corresponding environment variable fel_scriptaddr gets set. misc_init_r() also sets (or clears) the "fel_booted" variable depending on the active boot device, using the same logic as spl_boot_device(). The goal is to provide sufficient information (within the U-Boot environment) to make intelligent decisions on how to continue the boot process, allowing specific customizations for the "FEL boot" case. Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-09-29sunxi: Simplify spl board_init_f functionHans de Goede
crt0.S will both memset the bss sectioan and call board_init_r for us, so there is no need to do either ourselves. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Ian Campbell <ijc@hellion.org.uk>
2015-08-31sunxi: Enable non-secure access to RTC on sun6i (A31s)Chen-Yu Tsai
On the A31s the RTC is by default secured. Thus when u-boot loads the kernel in non-secure world, the RTC is unavailable. The SoC has a TrustZone Protection Controller, which can be used to enable non-secure access to the RTC. On the A31 the TZPC doesn't seem to do anything, i.e. changes to its register contents do not affect access to the RTC. Signed-off-by: Chen-Yu Tsai <wens@csie.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>