[PATCH v4 08/16] lib: sbi: Extend sbi_hsm_hart_start() for domains

[Anup Patel]

> -----Original Message-----
> From: Anup Patel <Anup.Patel at wdc.com>
> Sent: 20 October 2020 15:09
> To: Atish Patra <Atish.Patra at wdc.com>; Alistair Francis
> <Alistair.Francis at wdc.com>
> Cc: Anup Patel <anup at brainfault.org>; opensbi at lists.infradead.org; Anup
> Patel <Anup.Patel at wdc.com>
> Subject: [PATCH v4 08/16] lib: sbi: Extend sbi_hsm_hart_start() for domains
> 
> The sbi_hsm_hart_start() should consider the domain under which we are
> trying to start the HART. This will help ensure that HART A can start HART B
> only if both HARTs A and B belong to the same domain.
> 
> We also have a special case when we bring-up boot HART of non-root
> domains in sbi_domain_finalize() where we should skip domain checks in
> sbi_hsm_hart_start(). To achieve this, sbi_hsm_hart_start() should do
> domain checks only when domain parameter is non-NULL.
> 
> This patch extends sbi_hsm_hart_start() as-per above.
> 
> Signed-off-by: Anup Patel <anup.patel at wdc.com>
> Reviewed-by: Atish Patra <atish.patra at wdc.com>
> ---
>  include/sbi/sbi_hsm.h   |  5 +++--
>  lib/sbi/sbi_domain.c    |  6 ++++--
>  lib/sbi/sbi_ecall_hsm.c |  4 ++--
>  lib/sbi/sbi_hsm.c       | 19 ++++++++++---------
>  4 files changed, 19 insertions(+), 15 deletions(-)
> 
> diff --git a/include/sbi/sbi_hsm.h b/include/sbi/sbi_hsm.h index
> 296b267..4823383 100644
> --- a/include/sbi/sbi_hsm.h
> +++ b/include/sbi/sbi_hsm.h
> @@ -25,8 +25,9 @@ struct sbi_scratch;
>  int sbi_hsm_init(struct sbi_scratch *scratch, u32 hartid, bool cold_boot);
> void __noreturn sbi_hsm_exit(struct sbi_scratch *scratch);
> 
> -int sbi_hsm_hart_start(struct sbi_scratch *scratch, u32 hartid,
> -		       ulong saddr, ulong smode, ulong priv);
> +int sbi_hsm_hart_start(struct sbi_scratch *scratch,
> +		       const struct sbi_domain *dom,
> +		       u32 hartid, ulong saddr, ulong smode, ulong priv);
>  int sbi_hsm_hart_stop(struct sbi_scratch *scratch, bool exitnow);  int
> sbi_hsm_hart_get_state(const struct sbi_domain *dom, u32 hartid);  int
> sbi_hsm_hart_state_to_status(int state); diff --git a/lib/sbi/sbi_domain.c
> b/lib/sbi/sbi_domain.c index 86dfefd..9bde5fb 100644
> --- a/lib/sbi/sbi_domain.c
> +++ b/lib/sbi/sbi_domain.c
> @@ -324,8 +324,10 @@ int sbi_domain_finalize(struct sbi_scratch *scratch,
> u32 cold_hartid)
>  			scratch->next_mode = dom->next_mode;
>  			scratch->next_arg1 = dom->next_arg1;
>  		} else {
> -			rc = sbi_hsm_hart_start(scratch, dhart, dom-
> >next_addr,
> -					dom->next_mode, dom-
> >next_arg1);
> +			rc = sbi_hsm_hart_start(scratch, NULL, dhart,
> +						dom->next_addr,
> +						dom->next_mode,
> +						dom->next_arg1);
>  			if (rc)
>  				return rc;
>  		}
> diff --git a/lib/sbi/sbi_ecall_hsm.c b/lib/sbi/sbi_ecall_hsm.c index
> 3698a41..376740c 100644
> --- a/lib/sbi/sbi_ecall_hsm.c
> +++ b/lib/sbi/sbi_ecall_hsm.c
> @@ -28,8 +28,8 @@ static int sbi_ecall_hsm_handler(unsigned long extid,
> unsigned long funcid,
>  	case SBI_EXT_HSM_HART_START:
>  		smode = csr_read(CSR_MSTATUS);
>  		smode = (smode & MSTATUS_MPP) >>
> MSTATUS_MPP_SHIFT;
> -		ret = sbi_hsm_hart_start(scratch, args[0], args[1],
> -					 smode, args[2]);
> +		ret = sbi_hsm_hart_start(scratch, sbi_domain_thishart_ptr(),
> +					 args[0], args[1], smode, args[2]);
>  		break;
>  	case SBI_EXT_HSM_HART_STOP:
>  		ret = sbi_hsm_hart_stop(scratch, TRUE); diff --git
> a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c index 65e7f3d..8121efb 100644
> --- a/lib/sbi/sbi_hsm.c
> +++ b/lib/sbi/sbi_hsm.c
> @@ -205,17 +205,23 @@ fail_exit:
>  	sbi_hart_hang();
>  }
> 
> -int sbi_hsm_hart_start(struct sbi_scratch *scratch, u32 hartid,
> -		       ulong saddr, ulong smode, ulong priv)
> +int sbi_hsm_hart_start(struct sbi_scratch *scratch,
> +		       const struct sbi_domain *dom,
> +		       u32 hartid, ulong saddr, ulong smode, ulong priv)
>  {
> -	int rc;
>  	unsigned long init_count;
>  	unsigned int hstate;
>  	struct sbi_scratch *rscratch;
>  	struct sbi_hsm_data *hdata;
>  	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
> 
> -	if (smode != PRV_M && smode != PRV_S && smode != PRV_U)
> +	/* For now, we only allow start mode to be S-mode or U-mode. */
> +	if (smode != PRV_S && smode != PRV_U)
> +		return SBI_EINVAL;
> +	if (dom && !sbi_domain_is_assigned_hart(dom, hartid))
> +		return SBI_EINVAL;
> +	if (dom && !sbi_domain_check_addr(dom, saddr, smode,
> +					  SBI_DOMAIN_EXECUTE))
>  		return SBI_EINVAL;
> 
>  	rscratch = sbi_hartid_to_scratch(hartid); @@ -234,11 +240,6 @@ int
> sbi_hsm_hart_start(struct sbi_scratch *scratch, u32 hartid,
>  	if (hstate != SBI_HART_STOPPED)
>  		return SBI_EINVAL;
> 
> -	rc = sbi_hart_pmp_check_addr(scratch, saddr, smode, PMP_X);
> -	if (rc)
> -		return rc;
> -	//TODO: We also need to check saddr for valid physical address as
> well.
> -
>  	init_count = sbi_init_count(hartid);
>  	rscratch->next_arg1 = priv;
>  	rscratch->next_addr = saddr;
> --
> 2.25.1

Applied this patch to the riscv/opensbi repo

Regards,
Anup