From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Thu, 18 Jan 2018 10:14:06 +0000 Subject: [PATCH v6 02/12] drivers: base: cacheinfo: setup DT cache properties early In-Reply-To: <15884ccc-2cfb-da91-5844-369d8237175d@arm.com> References: <20180113005920.28658-1-jeremy.linton@arm.com> <20180113005920.28658-3-jeremy.linton@arm.com> <20180115123338.GB5473@e107155-lin> <65f78c99-8b86-0098-7ced-899840a4bf16@arm.com> <15884ccc-2cfb-da91-5844-369d8237175d@arm.com> Message-ID: <05a8b375-70c4-34d4-6cde-8dd4cd62c10b@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 17/01/18 18:51, Jeremy Linton wrote: > Hi, > > On 01/17/2018 12:20 PM, Sudeep Holla wrote: >> >> >> On 16/01/18 21:07, Jeremy Linton wrote: >>> Hi, >>> >>> On 01/15/2018 06:33 AM, Sudeep Holla wrote: >>>> On Fri, Jan 12, 2018 at 06:59:10PM -0600, Jeremy Linton wrote: >>>>> The original intent in cacheinfo was that an architecture >>>>> specific populate_cache_leaves() would probe the hardware >>>>> and then cache_shared_cpu_map_setup() and >>>>> cache_override_properties() would provide firmware help to >>>>> extend/expand upon what was probed. Arm64 was really >>>>> the only architecture that was working this way, and >>>>> with the removal of most of the hardware probing logic it >>>>> became clear that it was possible to simplify the logic a bit. >>>>> >>>>> This patch combines the walk of the DT nodes with the >>>>> code updating the cache size/line_size and nr_sets. >>>>> cache_override_properties() (which was DT specific) is >>>>> then removed. The result is that cacheinfo.of_node is >>>>> no longer used as a temporary place to hold DT references >>>>> for future calls that update cache properties. That change >>>>> helps to clarify its one remaining use (matching >>>>> cacheinfo nodes that represent shared caches) which >>>>> will be used by the ACPI/PPTT code in the following patches. >>>>> >>>>> Cc: Palmer Dabbelt >>>>> Cc: Albert Ou >>>>> Signed-off-by: Jeremy Linton >>>>> --- >>>>> ?? arch/riscv/kernel/cacheinfo.c |? 1 + >>>>> ?? drivers/base/cacheinfo.c????? | 65 >>>>> +++++++++++++++++++------------------------ >>>>> ?? include/linux/cacheinfo.h???? |? 1 + >>>>> ?? 3 files changed, 31 insertions(+), 36 deletions(-) >>>>> >>>>> diff --git a/arch/riscv/kernel/cacheinfo.c >>>>> b/arch/riscv/kernel/cacheinfo.c >>>>> index 10ed2749e246..6f4500233cf8 100644 >>>>> --- a/arch/riscv/kernel/cacheinfo.c >>>>> +++ b/arch/riscv/kernel/cacheinfo.c >>>>> @@ -30,6 +30,7 @@ static void ci_leaf_init(struct cacheinfo >>>>> *this_leaf, >>>>> ?????????? CACHE_WRITE_BACK >>>>> ?????????? | CACHE_READ_ALLOCATE >>>>> ?????????? | CACHE_WRITE_ALLOCATE; >>>>> +??? cache_of_set_props(this_leaf, node); >>>> >>>> This may be necessary but can it be done as later patch ? So far >>>> nothing >>>> is added that may break riscv IIUC. >>> >>> Well I think you have a bisection issue where the additional information >>> will disappear between this patch and wherever we put this code back in. >>> >> >> Hmm, I am sorry but I fail to see the issue. Before this change, >> populate_cache_leaves just populated the info as per ci_leaf_init in >> arch/riscv/kernel/cacheinfo.c and cache_override_properties used to fill >> the remaining. >> >> After this patch, the same is achieved in cache_shared_cpu_map_setup. >> >> In both case, it was by the end of detect_cache_attributes, so I see no >> issue. >> > > > Hi, > > I must be misunderstanding something. > Looks like I was missing to understand something :) > AFAIK, The code in cache_setup_of_node() won't call cache_of_set_props() > because it returns when there is an existing of_node (fw_unique) created > by the riscv populate_cache_leaves(). That's why I'm making the direct > call here. If we fail to get that change in place before > cache_override_properties() is removed then the fields not set by the > riscv code (size/etc) will be missing. Indeed. I am trying to avoid use of cache_of_set_props outside. How about skipping setting up of fw_unique in ci_leaf_init instead ? -- Regards, Sudeep