On 2020-03-25 20:34:02 Wed, Nicholas Piggin wrote:
> In the interest of reducing code and possible failures in the
> machine check and system reset paths, grab the "ibm,nmi-interlock"
> token at init time.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mah...@linux.ibm.com>
Thanks,
-Mahesh.
> ---
> arch/powerpc/include/asm/firmware.h | 1 +
> arch/powerpc/platforms/pseries/ras.c | 2 +-
> arch/powerpc/platforms/pseries/setup.c | 13 ++++++++++---
> 3 files changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/firmware.h
> b/arch/powerpc/include/asm/firmware.h
> index ca33f4ef6cb4..6003c2e533a0 100644
> --- a/arch/powerpc/include/asm/firmware.h
> +++ b/arch/powerpc/include/asm/firmware.h
> @@ -128,6 +128,7 @@ extern void machine_check_fwnmi(void);
>
> /* This is true if we are using the firmware NMI handler (typically LPAR) */
> extern int fwnmi_active;
> +extern int ibm_nmi_interlock_token;
>
> extern unsigned int __start___fw_ftr_fixup, __stop___fw_ftr_fixup;
>
> diff --git a/arch/powerpc/platforms/pseries/ras.c
> b/arch/powerpc/platforms/pseries/ras.c
> index 1d7f973c647b..c74d5e740922 100644
> --- a/arch/powerpc/platforms/pseries/ras.c
> +++ b/arch/powerpc/platforms/pseries/ras.c
> @@ -458,7 +458,7 @@ static struct rtas_error_log *fwnmi_get_errinfo(struct
> pt_regs *regs)
> */
> static void fwnmi_release_errinfo(void)
> {
> - int ret = rtas_call(rtas_token("ibm,nmi-interlock"), 0, 1, NULL);
> + int ret = rtas_call(ibm_nmi_interlock_token, 0, 1, NULL);
> if (ret != 0)
> printk(KERN_ERR "FWNMI: nmi-interlock failed: %d\n", ret);
> }
> diff --git a/arch/powerpc/platforms/pseries/setup.c
> b/arch/powerpc/platforms/pseries/setup.c
> index 17d17f064a2d..c31acd7ce0c0 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -83,6 +83,7 @@ unsigned long CMO_PageSize = (ASM_CONST(1) <<
> IOMMU_PAGE_SHIFT_4K);
> EXPORT_SYMBOL(CMO_PageSize);
>
> int fwnmi_active; /* TRUE if an FWNMI handler is present */
> +int ibm_nmi_interlock_token;
>
> static void pSeries_show_cpuinfo(struct seq_file *m)
> {
> @@ -113,9 +114,14 @@ static void __init fwnmi_init(void)
> struct slb_entry *slb_ptr;
> size_t size;
> #endif
> + int ibm_nmi_register_token;
>
> - int ibm_nmi_register = rtas_token("ibm,nmi-register");
> - if (ibm_nmi_register == RTAS_UNKNOWN_SERVICE)
> + ibm_nmi_register_token = rtas_token("ibm,nmi-register");
> + if (ibm_nmi_register_token == RTAS_UNKNOWN_SERVICE)
> + return;
> +
> + ibm_nmi_interlock_token = rtas_token("ibm,nmi-interlock");
> + if (WARN_ON(ibm_nmi_interlock_token == RTAS_UNKNOWN_SERVICE))
> return;
>
> /* If the kernel's not linked at zero we point the firmware at low
> @@ -123,7 +129,8 @@ static void __init fwnmi_init(void)
> system_reset_addr = __pa(system_reset_fwnmi) - PHYSICAL_START;
> machine_check_addr = __pa(machine_check_fwnmi) - PHYSICAL_START;
>
> - if (0 == rtas_call(ibm_nmi_register, 2, 1, NULL, system_reset_addr,
> + if (0 == rtas_call(ibm_nmi_register_token, 2, 1, NULL,
> + system_reset_addr,
> machine_check_addr))
> fwnmi_active = 1;
>
> --
> 2.23.0
>
--
Mahesh J Salgaonkar
