Hi Mykola,
Sequence of next 3 patches (and previous one) really puzzles me. Can you
first implement hyp_resume() function, then add PSCI_SYSTEM_SUSPEND call
and only then implement system_suspend() function? Why do this backwards?
Mykola Kvach <xakep.ama...@gmail.com> writes:
> From: Mirela Simonovic <mirela.simono...@aggios.com>
>
> Invoke PSCI SYSTEM_SUSPEND to finalize Xen's suspend sequence on ARM64
> platforms.
> Pass the resume entry point (hyp_resume) as the first argument to EL3. The
> resume
> handler is currently a stub and will be implemented later in assembly. Ignore
> the
> context ID argument, as is done in Linux.
>
> Only enable this path when CONFIG_SYSTEM_SUSPEND is set and
> PSCI version is >= 1.0.
>
> Signed-off-by: Mirela Simonovic <mirela.simono...@aggios.com>
> Signed-off-by: Saeed Nowshadi <saeed.nowsh...@xilinx.com>
> Signed-off-by: Mykyta Poturai <mykyta_potu...@epam.com>
> Signed-off-by: Mykola Kvach <mykola_kv...@epam.com>
> ---
> Changes in v4:
> - select the appropriate PSCI SYSTEM_SUSPEND function ID based on platform
> - update comments and commit message to reflect recent changes
>
> Changes in v3:
> - return PSCI_NOT_SUPPORTED instead of a hardcoded 1 on ARM32
> - check PSCI version before invoking SYSTEM_SUSPEND in
> call_psci_system_suspend
> ---
> xen/arch/arm/arm64/head.S | 8 ++++++++
> xen/arch/arm/include/asm/psci.h | 1 +
> xen/arch/arm/include/asm/suspend.h | 2 ++
> xen/arch/arm/psci.c | 23 ++++++++++++++++++++++-
> xen/arch/arm/suspend.c | 5 +++++
> 5 files changed, 38 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
> index 72c7b24498..3522c497c5 100644
> --- a/xen/arch/arm/arm64/head.S
> +++ b/xen/arch/arm/arm64/head.S
> @@ -561,6 +561,14 @@ END(efi_xen_start)
>
> #endif /* CONFIG_ARM_EFI */
>
> +#ifdef CONFIG_SYSTEM_SUSPEND
> +
> +FUNC(hyp_resume)
> + b .
> +END(hyp_resume)
> +
> +#endif /* CONFIG_SYSTEM_SUSPEND */
> +
> /*
> * Local variables:
> * mode: ASM
> diff --git a/xen/arch/arm/include/asm/psci.h b/xen/arch/arm/include/asm/psci.h
> index 48a93e6b79..bb3c73496e 100644
> --- a/xen/arch/arm/include/asm/psci.h
> +++ b/xen/arch/arm/include/asm/psci.h
> @@ -23,6 +23,7 @@ int call_psci_cpu_on(int cpu);
> void call_psci_cpu_off(void);
> void call_psci_system_off(void);
> void call_psci_system_reset(void);
> +int call_psci_system_suspend(void);
>
> /* Range of allocated PSCI function numbers */
> #define PSCI_FNUM_MIN_VALUE _AC(0,U)
> diff --git a/xen/arch/arm/include/asm/suspend.h
> b/xen/arch/arm/include/asm/suspend.h
> index 78d0e2383b..55041a5d06 100644
> --- a/xen/arch/arm/include/asm/suspend.h
> +++ b/xen/arch/arm/include/asm/suspend.h
> @@ -7,6 +7,8 @@
>
> int host_system_suspend(void);
>
> +void hyp_resume(void);
> +
> #endif /* CONFIG_SYSTEM_SUSPEND */
>
> #endif /* __ASM_ARM_SUSPEND_H__ */
> diff --git a/xen/arch/arm/psci.c b/xen/arch/arm/psci.c
> index b6860a7760..c9d126b195 100644
> --- a/xen/arch/arm/psci.c
> +++ b/xen/arch/arm/psci.c
> @@ -17,17 +17,20 @@
> #include <asm/cpufeature.h>
> #include <asm/psci.h>
> #include <asm/acpi.h>
> +#include <asm/suspend.h>
>
> /*
> * While a 64-bit OS can make calls with SMC32 calling conventions, for
> * some calls it is necessary to use SMC64 to pass or return 64-bit values.
> - * For such calls PSCI_0_2_FN_NATIVE(x) will choose the appropriate
> + * For such calls PSCI_*_FN_NATIVE(x) will choose the appropriate
> * (native-width) function ID.
> */
> #ifdef CONFIG_ARM_64
> #define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN64_##name
> +#define PSCI_1_0_FN_NATIVE(name) PSCI_1_0_FN64_##name
> #else
> #define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN32_##name
> +#define PSCI_1_0_FN_NATIVE(name) PSCI_1_0_FN32_##name
> #endif
>
> uint32_t psci_ver;
> @@ -60,6 +63,24 @@ void call_psci_cpu_off(void)
> }
> }
>
> +int call_psci_system_suspend(void)
> +{
> +#ifdef CONFIG_SYSTEM_SUSPEND
> + struct arm_smccc_res res;
> +
> + if ( psci_ver < PSCI_VERSION(1, 0) )
> + return PSCI_NOT_SUPPORTED;
> +
> + /* 2nd argument (context ID) is not used */
> + arm_smccc_smc(PSCI_1_0_FN_NATIVE(SYSTEM_SUSPEND), __pa(hyp_resume),
> &res);
> + return PSCI_RET(res);
> +#else
> + dprintk(XENLOG_WARNING,
> + "SYSTEM_SUSPEND not supported (CONFIG_SYSTEM_SUSPEND
> disabled)\n");
> + return PSCI_NOT_SUPPORTED;
> +#endif
> +}
> +
> void call_psci_system_off(void)
> {
> if ( psci_ver > PSCI_VERSION(0, 1) )
> diff --git a/xen/arch/arm/suspend.c b/xen/arch/arm/suspend.c
> index abf4b928ce..11e86b7f51 100644
> --- a/xen/arch/arm/suspend.c
> +++ b/xen/arch/arm/suspend.c
> @@ -1,5 +1,6 @@
> /* SPDX-License-Identifier: GPL-2.0-only */
>
> +#include <asm/psci.h>
> #include <xen/console.h>
> #include <xen/cpu.h>
> #include <xen/llc-coloring.h>
> @@ -70,6 +71,10 @@ static long system_suspend(void *data)
> */
> update_boot_mapping(true);
>
> + status = call_psci_system_suspend();
> + if ( status )
> + dprintk(XENLOG_WARNING, "PSCI system suspend failed, err=%d\n",
> status);
So this is where missing call to PSCI_SYSTEM_SUSPEND is...
> +
> system_state = SYS_STATE_resume;
> update_boot_mapping(false);
--
WBR, Volodymyr
