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u-boot-brain/arch/arm/cpu/armv8/Kconfig

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armv8/vexpress64: make multientry conditional While the Freescale ARMv8 board LS2085A will enter U-Boot both on a master and a secondary (slave) CPU, this is not the common behaviour on ARMv8 platforms. The norm is that U-Boot is entered from the master CPU only, while the other CPUs are kept in WFI (wait for interrupt) state. The code determining which CPU we are running on is using the MPIDR register, but the definition of that register varies with platform to some extent, and handling multi-cluster platforms (such as the Juno) will become cumbersome. It is better to only enable the multiple entry code on machines that actually need it and disable it by default. Make the single entry default and add a special ARMV8_MULTIENTRY KConfig option to be used by the platforms that need multientry and set it for the LS2085A. Delete all use of the CPU_RELEASE_ADDR from the Vexpress64 boards as it is just totally unused and misleading, and make it conditional in the generic start.S code. This makes the Juno platform start U-Boot properly. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-09 18:53:21 +09:00
if ARM64
config ARMV8_MULTIENTRY
kconfig: use bool instead of boolean for type definition attributes Linux stopped the use of keyword 'boolean' in Kconfig. Refer to commit 6341e62b212a2541efb0160c470e90bd226d5496 ("kconfig: use bool instead of boolean for type definition attributes") in Linux Kernel. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-08-12 10:26:50 +09:00
bool "Enable multiple CPUs to enter into U-Boot"
armv8/vexpress64: make multientry conditional While the Freescale ARMv8 board LS2085A will enter U-Boot both on a master and a secondary (slave) CPU, this is not the common behaviour on ARMv8 platforms. The norm is that U-Boot is entered from the master CPU only, while the other CPUs are kept in WFI (wait for interrupt) state. The code determining which CPU we are running on is using the MPIDR register, but the definition of that register varies with platform to some extent, and handling multi-cluster platforms (such as the Juno) will become cumbersome. It is better to only enable the multiple entry code on machines that actually need it and disable it by default. Make the single entry default and add a special ARMV8_MULTIENTRY KConfig option to be used by the platforms that need multientry and set it for the LS2085A. Delete all use of the CPU_RELEASE_ADDR from the Vexpress64 boards as it is just totally unused and misleading, and make it conditional in the generic start.S code. This makes the Juno platform start U-Boot properly. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-09 18:53:21 +09:00
arm64: add better and more generic spin-table support There are two enable methods supported by ARM64 Linux; psci and spin-table. The latter is simpler and helpful for quick SoC bring up. My main motivation for this patch is to improve the spin-table support, which allows us to boot an ARMv8 system without the ARM Trusted Firmware. Currently, we have multi-entry code in arch/arm/cpu/armv8/start.S and the spin-table is supported in a really ad-hoc way, and I see some problems: - We must hard-code CPU_RELEASE_ADDR so that it matches the "cpu-release-addr" property in the DT that comes from the kernel tree. - The Documentation/arm64/booting.txt in Linux requires that the release address must be zero-initialized, but it is not cared by the common code in U-Boot. We must do it in a board function. - There is no systematic way to protect the spin-table code from the kernel. We are supposed to do it in a board specific manner, but it is difficult to predict where the spin-table code will be located after the relocation. So, it also makes difficult to hard-code /memreserve/ in the DT of the kernel. So, here is a patch to solve those problems; the DT is run-time modified to reserve the spin-table code (+ cpu-release-addr). Also, the "cpu-release-addr" property is set to an appropriate address after the relocation, which means we no longer need the hard-coded CPU_RELEASE_ADDR. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-06-27 19:31:05 +09:00
config ARMV8_SPIN_TABLE
bool "Support spin-table enable method"
depends on ARMV8_MULTIENTRY && OF_LIBFDT
help
Say Y here to support "spin-table" enable method for booting Linux.
To use this feature, you must do:
- Specify enable-method = "spin-table" in each CPU node in the
Device Tree you are using to boot the kernel
- Let secondary CPUs in U-Boot (in a board specific manner)
before the master CPU jumps to the kernel
U-Boot automatically does:
- Set "cpu-release-addr" property of each CPU node
(overwrites it if already exists).
- Reserve the code for the spin-table and the release address
via a /memreserve/ region in the Device Tree.
armv8/vexpress64: make multientry conditional While the Freescale ARMv8 board LS2085A will enter U-Boot both on a master and a secondary (slave) CPU, this is not the common behaviour on ARMv8 platforms. The norm is that U-Boot is entered from the master CPU only, while the other CPUs are kept in WFI (wait for interrupt) state. The code determining which CPU we are running on is using the MPIDR register, but the definition of that register varies with platform to some extent, and handling multi-cluster platforms (such as the Juno) will become cumbersome. It is better to only enable the multiple entry code on machines that actually need it and disable it by default. Make the single entry default and add a special ARMV8_MULTIENTRY KConfig option to be used by the platforms that need multientry and set it for the LS2085A. Delete all use of the CPU_RELEASE_ADDR from the Vexpress64 boards as it is just totally unused and misleading, and make it conditional in the generic start.S code. This makes the Juno platform start U-Boot properly. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-09 18:53:21 +09:00
endif
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