[PATCH] powerpc/pseries: advertise Hot Plug Event support to firmware

[Nathan Fontenot]

On 02/20/2017 07:12 PM, Michael Roth wrote:
> With the inclusion of:
> 
>   powerpc/pseries: Implement indexed-count hotplug memory remove
>   powerpc/pseries: Implement indexed-count hotplug memory add
> 
> we now have complete handling of the RTAS hotplug event format
> as described by PAPR via ACR "PAPR Changes for Hotplug RTAS Events".
> 
> This capability is indicated by byte 6, bit 5 of architecture
> option vector 5, and allows for greater control over cpu/memory/pci
> hot plug/unplug operations.
> 
> Existing pseries kernels will utilize this capability based on the
> existence of the /event-sources/hot-plug-events DT property, so we
> only need to advertise it via CAS and do not need a corresponding
> FW_FEATURE_* value to test for.
> 
> Cc: Michael Ellerman <mpe at ellerman.id.au>
> Cc: Nathan Fontenot <nfont at linux.vnet.ibm.com>
> Cc: David Gibson <david at gibson.dropbear.id.au>
> Signed-off-by: Michael Roth <mdroth at linux.vnet.ibm.com>

Reviewed-by: Nathan Fontenot <nfont at linux.vnet.ibm.com>

> ---
>  arch/powerpc/include/asm/prom.h | 1 +
>  arch/powerpc/kernel/prom_init.c | 2 +-
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
> index 2c8001c..4a90634 100644
> --- a/arch/powerpc/include/asm/prom.h
> +++ b/arch/powerpc/include/asm/prom.h
> @@ -153,6 +153,7 @@ struct of_drconf_cell {
>  #define OV5_XCMO		0x0440	/* Page Coalescing */
>  #define OV5_TYPE1_AFFINITY	0x0580	/* Type 1 NUMA affinity */
>  #define OV5_PRRN		0x0540	/* Platform Resource Reassignment */
> +#define OV5_HP_EVT		0x0604	/* Hot Plug Event support */
>  #define OV5_RESIZE_HPT		0x0601	/* Hash Page Table resizing */
>  #define OV5_PFO_HW_RNG		0x1180	/* PFO Random Number Generator */
>  #define OV5_PFO_HW_842		0x1140	/* PFO Compression Accelerator */
> diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
> index f3c8799..1a835e7 100644
> --- a/arch/powerpc/kernel/prom_init.c
> +++ b/arch/powerpc/kernel/prom_init.c
> @@ -839,7 +839,7 @@ struct ibm_arch_vec __cacheline_aligned ibm_architecture_vec = {
>  		0,
>  #endif
>  		.associativity = OV5_FEAT(OV5_TYPE1_AFFINITY) | OV5_FEAT(OV5_PRRN),
> -		.bin_opts = OV5_FEAT(OV5_RESIZE_HPT),
> +		.bin_opts = OV5_FEAT(OV5_RESIZE_HPT) | OV5_FEAT(OV5_HP_EVT),
>  		.micro_checkpoint = 0,
>  		.reserved0 = 0,
>  		.max_cpus = cpu_to_be32(NR_CPUS),	/* number of cores supported */
>