[PATCH] remoteproc: pru: Fix firmware loading crashes on K3 SoCs

[Suman Anna]

On 3/23/21 6:20 PM, Mathieu Poirier wrote:
> On Mon, Mar 15, 2021 at 03:58:59PM -0500, Suman Anna wrote:
>> The K3 PRUs are 32-bit processors and in general have some limitations
>> in using the standard ARMv8 memcpy function for loading firmware segments,
>> so the driver already uses a custom memcpy implementation. This added
>> logic however is limited to only IRAMs at the moment, but the loading
>> into Data RAMs is not completely ok either and does generate a kernel
>> crash for unaligned accesses.
>>
>> Fix these crashes by removing the existing IRAM logic limitation and
>> extending the custom memcpy usage to Data RAMs as well for all K3 SoCs.
>>
>> Fixes: 1d39f4d19921 ("remoteproc: pru: Add support for various PRU cores on K3 AM65x SoCs")
>> Signed-off-by: Suman Anna <s-anna at ti.com>
> 
> Probably a good idea to CC stable as well...
> 
> Reviewed-by: Mathieu Poirier <mathieu.poirier at linaro.org>

Thanks Mathieu. This patch is already staged on Bjorn's rproc-fixes branch
though and part of linux-next since next-20210319. I have posted an additional
3-patch series for some more PRU fixes. Do you want me to post a v2 for those
with stable Cc'd?

regards
Suman

> 
>> ---
>>  drivers/remoteproc/pru_rproc.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
>> index 2667919d76b3..16979c1cd2f4 100644
>> --- a/drivers/remoteproc/pru_rproc.c
>> +++ b/drivers/remoteproc/pru_rproc.c
>> @@ -585,7 +585,7 @@ pru_rproc_load_elf_segments(struct rproc *rproc, const struct firmware *fw)
>>  			break;
>>  		}
>>  
>> -		if (pru->data->is_k3 && is_iram) {
>> +		if (pru->data->is_k3) {
>>  			ret = pru_rproc_memcpy(ptr, elf_data + phdr->p_offset,
>>  					       filesz);
>>  			if (ret) {
>> -- 
>> 2.30.1
>>