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2019-08-26riscv: add SPL supportLukas Auer
U-Boot SPL on the generic RISC-V CPU supports two boot flows, directly jumping to the image and via OpenSBI firmware. In the first case, both U-Boot SPL and proper must be compiled to run in the same privilege mode. Using OpenSBI firmware, U-Boot SPL must be compiled for machine mode and U-Boot proper for supervisor mode. To be able to use SPL, boards have to provide a supported SPL boot device. Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Tested-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26riscv: add run mode configuration for SPLLukas Auer
U-Boot SPL can be run in a different privilege mode from U-Boot proper. Add new configuration entries for SPL to allow the run mode to be configured independently of U-Boot proper. Extend all uses of the CONFIG_RISCV_SMODE and CONFIG_RISCV_MMODE configuration symbols to also cover the SPL equivalents. Ensure that files compatible with only one privilege mode are not included in builds targeting an incompatible privilege mode. Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> Tested-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-02-27riscv: generic: Ensure that U-Boot runs within 4GB for 64bit systemsAnup Patel
On 64bit systems, the DRAM top can be easily beyond 4GB and U-Boot DMA mapping APIs will generate DMA addresses beyond 4GB. This breaks DMA programming in 32bit DMA capable devices (such as Cadence MACB ethernet). For example, If DRAM is more then 2GB on QEMU sifive_u machine then Cadence MACB ethernet stops working for U-Boot because it is a 32bit DMA capable device. To handle 32bit DMA capable devices on 64bit systems, we provide custom implementation of board_get_usable_ram_top() which ensures that usable ram top is not more then 4GB. This in-turn ensures that U-Boot always runs within 4GB hence DMA addresses generated by DMA mapping APIs will be within 4GB too. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alexander Graf <agraf@suse.de> Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-02-27riscv: Rename cpu/qemu to cpu/genericAnup Patel
The QEMU CPU support under arch/riscv is pretty much generic and works fine for SiFive Unleashed as well. In fact, there will be quite a few RISC-V SOCs for which QEMU CPU support will work fine. This patch renames cpu/qemu to cpu/generic to indicate the above fact. If there are SOC specific errata workarounds required in cpu/generic then those can be done at runtime in cpu/generic based on CPU vendor specific DT compatible string. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alexander Graf <agraf@suse.de> Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>