Hello Mathieu,
On 5/28/24 23:30, Mathieu Poirier wrote:
> On Tue, May 21, 2024 at 10:09:59AM +0200, Arnaud Pouliquen wrote:
>> 1) on start:
>> - Using the TEE loader, the resource table is loaded by an external entity.
>> In such case the resource table address is not find from the firmware but
>> provided by the TEE remoteproc framework.
>> Use the rproc_get_loaded_rsc_table instead of rproc_find_loaded_rsc_table
>> - test that rproc->cached_table is not null before performing the memcpy
>>
>> 2)on stop
>> The use of the cached_table seems mandatory:
>> - during recovery sequence to have a snapshot of the resource table
>> resources used,
>> - on stop to allow for the deinitialization of resources after the
>> the remote processor has been shutdown.
>> However if the TEE interface is being used, we first need to unmap the
>> table_ptr before setting it to rproc->cached_table.
>> The update of rproc->table_ptr to rproc->cached_table is performed in
>> tee_remoteproc.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliq...@foss.st.com>
>> ---
>> drivers/remoteproc/remoteproc_core.c | 31 +++++++++++++++++++++-------
>> 1 file changed, 23 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/remoteproc/remoteproc_core.c
>> b/drivers/remoteproc/remoteproc_core.c
>> index 42bca01f3bde..3a642151c983 100644
>> --- a/drivers/remoteproc/remoteproc_core.c
>> +++ b/drivers/remoteproc/remoteproc_core.c
>> @@ -1267,6 +1267,7 @@ EXPORT_SYMBOL(rproc_resource_cleanup);
>> static int rproc_set_rsc_table_on_start(struct rproc *rproc, const struct
>> firmware *fw)
>> {
>> struct resource_table *loaded_table;
>> + struct device *dev = &rproc->dev;
>>
>> /*
>> * The starting device has been given the rproc->cached_table as the
>> @@ -1276,12 +1277,21 @@ static int rproc_set_rsc_table_on_start(struct rproc
>> *rproc, const struct firmwa
>> * this information to device memory. We also update the table_ptr so
>> * that any subsequent changes will be applied to the loaded version.
>> */
>> - loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
>> - if (loaded_table) {
>> - memcpy(loaded_table, rproc->cached_table, rproc->table_sz);
>> - rproc->table_ptr = loaded_table;
>> + if (rproc->tee_interface) {
>> + loaded_table = rproc_get_loaded_rsc_table(rproc,
>> &rproc->table_sz);
>> + if (IS_ERR(loaded_table)) {
>> + dev_err(dev, "can't get resource table\n");
>> + return PTR_ERR(loaded_table);
>> + }
>> + } else {
>> + loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
>> }
>>
>> + if (loaded_table && rproc->cached_table)
>> + memcpy(loaded_table, rproc->cached_table, rproc->table_sz);
>> +
>
> Why is this not part of the else {} above as it was the case before this
> patch?
> And why was an extra check for ->cached_table added?
Here we have to cover 2 use cases if rproc->tee_interface is set.
1) The remote processor is in stop state
- loaded_table points to the resource table in the remote memory and
- rproc->cached_table is null
=> no memcopy
2) crash recovery
- loaded_table points to the resource table in the remote memory
- rproc-cached_table point to a copy of the resource table
=> need to perform the memcpy to reapply settings in the resource table
I can duplicate the memcpy in if{} and else{} but this will be similar code
as needed in both case.
Adding rproc->cached_table test if proc->tee_interface=NULL seems also
reasonable as a memcpy from 0 should not be performed.
>
> This should be a simple change, i.e introduce an if {} else {} block to take
> care of the two scenarios. Plus the comment is misplaced now.
What about split it in 2 patches?
- one adding the test on rproc->cached_table for the memcpy
- one adding the if {} else {}?
Thanks,
Arnaud
>
> More comments tomorrow.
>
> Thanks,
> Mathieu
>
>> + rproc->table_ptr = loaded_table;
>> +
>> return 0;
>> }
>>
>> @@ -1318,11 +1328,16 @@ static int rproc_reset_rsc_table_on_stop(struct
>> rproc *rproc)
>> kfree(rproc->clean_table);
>>
>> out:
>> - /*
>> - * Use a copy of the resource table for the remainder of the
>> - * shutdown process.
>> + /* If the remoteproc_tee interface is used, then we have first to unmap
>> the resource table
>> + * before updating the proc->table_ptr reference.
>> */
>> - rproc->table_ptr = rproc->cached_table;
>> + if (!rproc->tee_interface) {
>> + /*
>> + * Use a copy of the resource table for the remainder of the
>> + * shutdown process.
>> + */
>> + rproc->table_ptr = rproc->cached_table;
>> + }
>> return 0;
>> }
>>
>> --
>> 2.25.1
>>
