[U-Boot] [PATCH v2 3/9] riscv: implement IPI platform functions using SBI

[Atish Patra]

On 3/5/19 2:54 PM, Lukas Auer wrote:
> The supervisor binary interface (SBI) provides the necessary functions
> to implement the platform IPI functions riscv_send_ipi() and
> riscv_clear_ipi(). Use it to implement them.
> 
> This adds support for inter-processor interrupts (IPIs) on RISC-V CPUs
> running in supervisor mode. Support for machine mode is already
> available for CPUs that include the SiFive CLINT.
> 
> Signed-off-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> Reviewed-by: Anup Patel <anup.patel at wdc.com>
> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
> ---
> 
> Changes in v2: None
> 
>   arch/riscv/Kconfig       |  5 +++++
>   arch/riscv/lib/Makefile  |  1 +
>   arch/riscv/lib/sbi_ipi.c | 25 +++++++++++++++++++++++++
>   3 files changed, 31 insertions(+)
>   create mode 100644 arch/riscv/lib/sbi_ipi.c
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 4d7a115569..9da609b33b 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -139,4 +139,9 @@ config NR_CPUS
>   	  Stack memory is pre-allocated. U-Boot must therefore know the
>   	  maximum number of CPUs that may be present.
>   
> +config SBI_IPI
> +	bool
> +	default y if RISCV_SMODE
> +	depends on SMP
> +
>   endmenu
> diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
> index 19370f9749..35dbf643e4 100644
> --- a/arch/riscv/lib/Makefile
> +++ b/arch/riscv/lib/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_RISCV_RDTIME) += rdtime.o
>   obj-$(CONFIG_SIFIVE_CLINT) += sifive_clint.o
>   obj-y	+= interrupts.o
>   obj-y	+= reset.o
> +obj-$(CONFIG_SBI_IPI) += sbi_ipi.o
>   obj-y   += setjmp.o
>   obj-$(CONFIG_SMP) += smp.o
>   
> diff --git a/arch/riscv/lib/sbi_ipi.c b/arch/riscv/lib/sbi_ipi.c
> new file mode 100644
> index 0000000000..170346da68
> --- /dev/null
> +++ b/arch/riscv/lib/sbi_ipi.c
> @@ -0,0 +1,25 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2019 Fraunhofer AISEC,
> + * Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> + */
> +
> +#include <common.h>
> +#include <asm/sbi.h>
> +
> +int riscv_send_ipi(int hart)
> +{
> +	ulong mask;
> +
> +	mask = 1UL << hart;
> +	sbi_send_ipi(&mask);
> +
> +	return 0;
> +}
> +
> +int riscv_clear_ipi(int hart)
> +{
> +	sbi_clear_ipi();
> +
> +	return 0;
> +}
> 

LGTM.

Reviewed-by: Atish Patra <atish.patra at wdc.com>

Regards,
Atish