[U-Boot] [PATCH 1/4] crypto/fsl: Introduce API to save/restore job-ring context

[Bryan O'Donoghue]

On 25/04/2019 23:13, Breno Matheus Lima wrote:
> Hi Bryan,
> 
> Em ter, 23 de abr de 2019 às 07:20, Bryan O'Donoghue
> <bryan.odonoghue at linaro.org> escreveu:
>>
>> We need to handle the case where DEK blobs are passed to the BootROM. In
>> this case, unlike in HAB authentication the BootROM checks job-ring
>> ownership set to secure world.
>>
>> One possible solution is to set the job-ring ownership to the expected
>> state for DEK blobs and then restore to whatever the run-time wants.
>>
>> For the case where Linux runs in normal-world we would want to set the
>> job-ring ownership to normal-world.
>>
>> The first step in the ownership context switch dance is making an API to do
>> it.
>>
>> This patch introduces:
>>
>> void __weak sec_set_jr_context_secure(void);
>> void __weak sec_set_jr_context_normal(void);
>>
>> This can be over-ridden for a given architecture, as will be necessary for
>> the MPC85xxx
>>
>> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue at linaro.org>
>> ---
>>   drivers/crypto/fsl/jr.c | 38 ++++++++++++++++++++++++++++++++++++++
>>   include/fsl_sec.h       |  3 +++
>>   2 files changed, 41 insertions(+)
>>
>> diff --git a/drivers/crypto/fsl/jr.c b/drivers/crypto/fsl/jr.c
>> index cc8d3b02a5..7b13aa4a61 100644
>> --- a/drivers/crypto/fsl/jr.c
>> +++ b/drivers/crypto/fsl/jr.c
>> @@ -574,6 +574,44 @@ static int rng_init(uint8_t sec_idx)
>>          return ret;
>>   }
>>   #endif
>> +
>> +static void __sec_set_jr_context_secure(uint8_t sec_idx)
>> +{
>> +       ccsr_sec_t *sec = (void *)SEC_ADDR(sec_idx);
>> +       uint32_t jrown_ns;
>> +       int i;
>> +
>> +       for (i = 0; i < ARRAY_SIZE(sec->jrliodnr); i++) {
>> +               jrown_ns = sec_in32(&sec->jrliodnr[i].ms);
>> +               jrown_ns &= ~(JROWN_NS | JRMID_NS);
> 
> We have the following definition at drivers/crypto/fsl/jr.h:
> 
> #define JRMID_NS 0x00000001
> 
> Seems that we are setting JROWN_MID field which is not TrustZone
> related, from i.MX7D Security Reference Manual:
> 
> Job Ring Owner's MID. This field defines the MID of the bus master
> that is permitted to read or write the registers that are specific to
> a particular Job Ring. These registers include the job ring
> configuration registers, the interrupt registers, the CAAM Secure
> Memory Access Permissions and Secure Memory Access Group registers and
> the ring buffer registers.

Hrmm, just seeing your response now Breno.

What we have is:
include/fsl_sec.h:#define JR_MID    2    /* Matches ROM configuration */

There's a decent argument to read what the BootROM has set for JR_MID 
and write it back ...

Let me include that in v2.

---
bod