Re: [PATCH v2] cxl: Set the valid bit in PE for dedicated mode

[Frederic Barrat <fbarrat@linux.vnet.ibm.com>]

Le 04/09/2017 à 10:48, Vaibhav Jain a écrit :
> Make sure to set the valid-bit in software-state field of the
> populated PE. This was earlier missing for dedicated mode AFUs, hence
> was causing a PSL freeze when the AFU was activated.
> 
> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
> ---
> Changelog:
> 
> v2 -> Removed a call to smp_wmb() after setting the bit [Michael Ellerman]
> ---

Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>


> 
>   drivers/misc/cxl/native.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
> index 4a82c313cf71..75df74d59527 100644
> --- a/drivers/misc/cxl/native.c
> +++ b/drivers/misc/cxl/native.c
> @@ -897,6 +897,14 @@ int cxl_attach_dedicated_process_psl9(struct cxl_context *ctx, u64 wed, u64 amr)
>   	if (ctx->afu->adapter->native->sl_ops->update_dedicated_ivtes)
>   		afu->adapter->native->sl_ops->update_dedicated_ivtes(ctx);
> 
> +	ctx->elem->software_state = cpu_to_be32(CXL_PE_SOFTWARE_STATE_V);
> +	/*
> +	 * Ideally we should do a wmb() here to make sure the changes to the
> +	 * PE are visible to the card before we call afu_enable.
> +	 * On ppc64 though all mmios are preceded by a 'sync' instruction hence
> +	 * we dont dont need one here.
> +	 */
> +
>   	result = cxl_ops->afu_reset(afu);
>   	if (result)
>   		return result;
>