From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 401RGD2CH3zDqjw for ; Wed, 14 Mar 2018 20:27:48 +1100 (AEDT) In-Reply-To: <20180215154924.22005-1-vaibhav@linux.vnet.ibm.com> To: Vaibhav Jain , linuxppc-dev@lists.ozlabs.org, Frederic Barrat From: Michael Ellerman Cc: Philippe Bergheaud , Alastair D'Silva , Vaibhav Jain , Andrew Donnellan , Christophe Lombard Subject: Re: [v2] cxl: Check if PSL data-cache is available before issue flush request Message-Id: <401RGD0D76z9sVV@ozlabs.org> Date: Wed, 14 Mar 2018 20:27:47 +1100 (AEDT) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2018-02-15 at 15:49:24 UTC, Vaibhav Jain wrote: > PSL9D doesn't have a data-cache that needs to be flushed before > resetting the card. However when cxl tries to flush data-cache on such > a card, it times-out as PSL_Control register never indicates flush > operation complete due to missing data-cache. This is usually > indicated in the kernel logs with this message: > > "WARNING: cache flush timed out" > > To fix this the patch checks PSL_Debug register CDC-Field(BIT:27) > which indicates the absence of a data-cache and sets a flag > 'no_data_cache' in 'struct cxl_native' to indicate this. When > cxl_data_cache_flush() is called it checks the flag and if set bails > out early without requesting a data-cache flush operation to the PSL. > > Signed-off-by: Vaibhav Jain > Acked-by: Andrew Donnellan > Acked-by: Frederic Barrat Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/94322ed8e857e3b2a33cf75118051a cheers