Re: [Qemu-devel] [PATCH v2 14/23] target-arm: add banked coprocessor register type and macros

[Sergey Fedorov]

On 22.05.2014 15:49, Aggeler Fabian wrote:
> On 22 May 2014, at 09:41, Edgar E. Iglesias <address@hidden> wrote:
>
>> On Tue, May 13, 2014 at 06:15:59PM +0200, Fabian Aggeler wrote:
>>> Banked CP registers can be defined with a A32_BANKED_REG macro which defines
>>> a non-secure instance of the register followed by an adjacent secure 
>>> instance.
>>> Using a union makes the code backwards-compatible since the non-secure
>>> instance can normally be accessed by its existing name.
>>>
>>> When translating a banked CP register access instruction in monitor mode,
>>> the SCR.NS bit determines which instance is going to be accessed.
>>>
>>> If EL3 is operating in Aarch64 state coprocessor registers are not
>>> banked anymore but in some cases have its own _EL3 instance.
>> Hi
>>
>> Regarding the sctlr regs and the banking of S/NS regs in general, I
>> think the general pattern should be to arrayify the regs that need
>> to be indexed by EL.
>>
>> This is an example of a structure (indexed by EL) with the aarch32
>> struct beeing here to help clarify.
>> union {
>>    struct {
>>        uint64_t pad;
>>        uint64_t sctlr_ns;
>>        uint64_t hsctlr;
>>        uint64_t sctlr_s;
>>    } aarch32;
>>    uint64_t sctlr_el[4];
>> }
>>
>> I think we would naturally want to register this for AArch32 as banked
>> with NS=sctlr_el[1] and S=sctlr_el[3].
>>
>> Another register example is FAR. For FAR, things look like this
>> (when EL2 is available and ignoring DFAR for clarity):
>> union {
>>    struct {
>>        uint64_t pad;
>>        uint64_t ifar_ns;
>>        uint64_t ifar_s;
>>    } aarch32;
>>    uint64_t far_el[4];
>> }
>>
>> Preferably we need something that can handle both cases.
>> An option could be to arrayify the .fieldoffset in reginfos?
>> If we don't want hardcoded TZ knowledge in the generic cpreg accessors,
>> maybe there could be a generic function that returns the .fieldoffset
>> index based on CPUState (e.g NS=0, S=1 etc). Or maybe specialized
>> read/write fns would be enough.
>>
>> Just an idea to get the discussion going.
>>
>> struct ARMCPRegInfo {
>> ....
>>    union {
>>        ptrdiff_t fieldoffset;
>>        ptrdiff_t fieldoffsets[2];
>>    };
>> };
>>
>> unsigned int arm_cpreg_tzbank_idx(CPUARMState *env)
>> {
>>    return is_a64(env) ? 0 : arm_is_secure(env);
>> }
>>
>> Example:
>>    { .name = "FAR_EL1", .state = ARM_CP_STATE_BOTH,
>>      .opc0 = 3, .crn = 6, .crm = 0, .opc1 = 0, .opc2 = 0,
>>      .access = PL1_RW,
>>      .fieldindex_fn = arm_cpreg_tzbank_idx,
>>      .fieldoffsets[] = { offsetof(CPUARMState, cp15.far_el[1]),
>>                          offsetof(CPUARMState, cp15.far_el[2])},
>>      .resetvalue = 0, },
>>
>>      ARMCPRegInfo sctlr = {
>>          .name = "SCTLR", .state = ARM_CP_STATE_BOTH,
>>          .opc0 = 3, .crn = 1, .crm = 0, .opc1 = 0, .opc2 = 0,
>>          .access = PL1_RW,
>>          .fieldindex_fn = arm_cpreg_tzbank_idx,
>>          .fieldoffsets[] = { offsetof(CPUARMState, cp15.sctlr_el[1]),
>>                              offsetof(CPUARMState, cp15.sctlr_el[3]),
>>          },
>>          /* Assuming raw_write and raw_read respect the indexing.  */
>>          .writefn = sctlr_write, .resetvalue = cpu->reset_sctlr,
>>          .raw_writefn = raw_write,
>>      };
>>
>> Best regards,
>> Edgar
>>
> Hi Edgar
>
> Thanks for joining the discussion. I like the idea of arrayifying the cp 
> regs, also for banking. 
> Since your patches are doing this anyways for EL registers I wanted to change 
> the registers
> which do not have EL3/EL2 equivalents (DACR, PAR,…) to use the same 
> mechanism. These
> registers are the third case which you haven’t mentioned in your examples 
> above, where we only
> have one reg in Aarch64 but two (s/ns) in Aarch32. So I in my eyes it didn’t 
> make sense to make
> the array bigger than needed, that’s why I went for 2 entries only. But if it 
> allows us map it easier
> or in a more consistent way I don’t see why we cannot do it.
>
> union {
>    struct {
>        uint64_t par_ns;
>        uint64_t par_s;
>    } aarch32;
>    uint64_t par_el[2];
> }
>
> We should probably also get rid of the macros I used to define the banked 
> registers, to make the code 
> look more uniform. Using your idea of arrayifying fieldset too, we could get 
> rid of the additional cpreg 
> definitions. Do we need to specify a .fieldindex_fn for every cpreg in this 
> case? 
> Isn’t it the same for all the cpregs which are banked (two fieldoffsets, the 
> first one for non-secure and
> the second entry for secure)? But then we still need to know whether this 
> register is banked or common.
>
> But what about accessing them not from within a cpreg read/write instruction? 
> We will have at least 3 
> cases of different indexes ({ns=1, s=2}, {ns=1, s=3}, {ns=0, s=1}). Although 
> by padding the last case 
> we could merge it with the first one so we only have 2 ways of accessing a 
> banked register, which was
> also the case in my patches, for which I introduced macros. Any ideas how to 
> simplify that?
>
> Thanks,
> Fabian

Hi

Speculating on some changes to reginfo's fieldoffset, it is worth to
notice that then CPU state save/load could need to be adjusted. Keeping
separate reginfo for each banked register in the hash table would
eliminate any changes to CPU state save/load.

Regards,
Sergey

>>
>>
>>
>>> Signed-off-by: Sergey Fedorov <address@hidden>
>>> Signed-off-by: Fabian Aggeler <address@hidden>
>>> ---
>>> target-arm/cpu.h       | 121 
>>> +++++++++++++++++++++++++++++++++++++++++++++----
>>> target-arm/helper.c    |  64 ++++++++++++++++++++++++--
>>> target-arm/translate.c |  19 +++++---
>>> 3 files changed, 184 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/target-arm/cpu.h b/target-arm/cpu.h
>>> index a970d55..9e325ac 100644
>>> --- a/target-arm/cpu.h
>>> +++ b/target-arm/cpu.h
>>> @@ -80,6 +80,16 @@
>>> #define offsetofhigh32(S, M) (offsetof(S, M) + sizeof(uint32_t))
>>> #endif
>>>
>>> +/* Define a banked coprocessor register state field. Use %name as the
>>> + * register field name for the secure instance. The non-secure instance
>>> + * has a "_nonsecure" suffix.
>>> + */
>>> +#define A32_BANKED_REG(type, name) \
>>> +    union { \
>>> +        type name; \
>>> +        type name##_banked[2]; \
>>> +    }
>>> +
>>> /* Meanings of the ARMCPU object's two inbound GPIO lines */
>>> #define ARM_CPU_IRQ 0
>>> #define ARM_CPU_FIQ 1
>>> @@ -89,6 +99,7 @@ typedef void ARMWriteCPFunc(void *opaque, int cp_info,
>>> typedef uint32_t ARMReadCPFunc(void *opaque, int cp_info,
>>>                                int dstreg, int operand);
>>>
>>> +
>>> struct arm_boot_info;
>>>
>>> #define NB_MMU_MODES 5
>>> @@ -673,6 +684,78 @@ static inline bool arm_el_is_aa64(CPUARMState *env, 
>>> int el)
>>>     return arm_feature(env, ARM_FEATURE_AARCH64);
>>> }
>>>
>>> +/* When EL3 is operating in Aarch32 state, the NS-bit determines
>>> + * whether the secure instance of a cp-register should be used. */
>>> +#define USE_SECURE_REG(env) ( \
>>> +                        arm_feature(env, ARM_FEATURE_SECURITY_EXTENSIONS) 
>>> && \
>>> +                        !arm_el_is_aa64(env, 3) && \
>>> +                        !((env)->cp15.c1_scr & 1/*NS*/))
>>> +
>>> +#define NONSECURE_BANK 0
>>> +#define SECURE_BANK 1
>>> +
>>> +#define A32_BANKED_REG_GET(env, regname) \
>>> +    ((USE_SECURE_REG(env)) ? \
>>> +            (env)->cp15.regname##_banked[SECURE_BANK] : \
>>> +            (env)->cp15.regname)
>>> +
>>> +#define A32_MAPPED_EL3_REG_GET(env, regname) \
>>> +    (((arm_el_is_aa64(env, 3) && arm_current_pl(env) == 3) || \
>>> +      (USE_SECURE_REG(env))) ? \
>>> +            (env)->cp15.regname##_el3 : \
>>> +            (env)->cp15.regname##_el1)
>>> +
>>> +#define A32_BANKED_REG_SET(env, regname, val) \
>>> +        do { \
>>> +            if (USE_SECURE_REG(env)) { \
>>> +                (env)->cp15.regname##_banked[SECURE_BANK] = (val); \
>>> +            } else { \
>>> +                (env)->cp15.regname = (val); \
>>> +            } \
>>> +        } while (0)
>>> +
>>> +#define A32_MAPPED_EL3_REG_SET(env, regname, val) \
>>> +        do { \
>>> +            if ((arm_el_is_aa64(env, 3) && arm_current_pl(env) == 3) || \
>>> +                    (USE_SECURE_REG(env))) { \
>>> +                (env)->cp15.regname##_el3 = (val); \
>>> +            } else { \
>>> +                (env)->cp15.regname##_el1 = (val); \
>>> +            } \
>>> +        } while (0)
>>> +
>>> +
>>> +#define A32_BANKED_CURRENT_REG_GET(env, regname) \
>>> +    ((!arm_el_is_aa64(env, 3) && arm_is_secure(env)) ? \
>>> +            (env)->cp15.regname##_banked[SECURE_BANK] : \
>>> +            (env)->cp15.regname)
>>> +
>>> +#define A32_MAPPED_EL3_CURRENT_REG_GET(env, regname) \
>>> +    (((arm_el_is_aa64(env, 3) && arm_current_pl(env) == 3) || \
>>> +      (!arm_el_is_aa64(env, 3) && arm_is_secure(env))) ? \
>>> +            (env)->cp15.regname##_el3 : \
>>> +            (env)->cp15.regname##_el1)
>>> +
>>> +#define A32_BANKED_CURRENT_REG_SET(env, regname, val) \
>>> +        do { \
>>> +            if (!arm_el_is_aa64(env, 3) && arm_is_secure(env)) { \
>>> +                (env)->cp15.regname##_banked[SECURE_BANK] = (val); \
>>> +            } else { \
>>> +                (env)->cp15.regname = (val); \
>>> +            } \
>>> +        } while (0)
>>> +
>>> +#define A32_MAPPED_EL3_CURRENT_REG_SET(env, regname, val) \
>>> +        do { \
>>> +            if ((arm_el_is_aa64(env, 3) && arm_current_pl(env) == 3) || \
>>> +                    (!arm_el_is_aa64(env, 3) && arm_is_secure(env))) { \
>>> +                (env)->cp15.regname##_el3 = (val); \
>>> +            } else { \
>>> +                (env)->cp15.regname##_el1 = (val); \
>>> +            } \
>>> +        } while (0)
>>> +
>>> +
>>> void arm_cpu_list(FILE *f, fprintf_function cpu_fprintf);
>>>
>>> /* Interface between CPU and Interrupt controller.  */
>>> @@ -691,6 +774,7 @@ void armv7m_nvic_complete_irq(void *opaque, int irq);
>>>  *  Crn, Crm, opc1, opc2 fields
>>>  *  32 or 64 bit register (ie is it accessed via MRC/MCR
>>>  *    or via MRRC/MCRR?)
>>> + *  nonsecure/secure bank (Aarch32 only)
>>>  * We allow 4 bits for opc1 because MRRC/MCRR have a 4 bit field.
>>>  * (In this case crn and opc2 should be zero.)
>>>  * For AArch64, there is no 32/64 bit size distinction;
>>> @@ -708,9 +792,16 @@ void armv7m_nvic_complete_irq(void *opaque, int irq);
>>> #define CP_REG_AA64_SHIFT 28
>>> #define CP_REG_AA64_MASK (1 << CP_REG_AA64_SHIFT)
>>>
>>> -#define ENCODE_CP_REG(cp, is64, crn, crm, opc1, opc2)   \
>>> -    (((cp) << 16) | ((is64) << 15) | ((crn) << 11) |    \
>>> -     ((crm) << 7) | ((opc1) << 3) | (opc2))
>>> +/* To enable banking of coprocessor registers depending on ns-bit we
>>> + * add a bit to distinguish between secure and non-secure cpregs in the
>>> + * hashtable.
>>> + */
>>> +#define CP_REG_NS_SHIFT 27
>>> +#define CP_REG_NS_MASK(nsbit) (nsbit << CP_REG_NS_SHIFT)
>>> +
>>> +#define ENCODE_CP_REG(cp, is64, crn, crm, opc1, opc2, ns)   \
>>> +    (CP_REG_NS_MASK(ns) | ((cp) << 16) | ((is64) << 15) |   \
>>> +     ((crn) << 11) | ((crm) << 7) | ((opc1) << 3) | (opc2))
>>>
>>> #define ENCODE_AA64_CP_REG(cp, crn, crm, op0, op1, op2) \
>>>     (CP_REG_AA64_MASK |                                 \
>>> @@ -771,6 +862,14 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t 
>>> cpregid)
>>>  * IO indicates that this register does I/O and therefore its accesses
>>>  * need to be surrounded by gen_io_start()/gen_io_end(). In particular,
>>>  * registers which implement clocks or timers require this.
>>> + * In an implementation with Security Extensions supporting Aarch32 cp 
>>> regs can
>>> + * be banked or common. If a register is common it references the same 
>>> variable
>>> + * from both worlds (non-secure and secure). For cp regs which neither set
>>> + * ARM_CP_SECURE nor ARM_CP_NONSECURE (default) we assume it's common and 
>>> it
>>> + * will be inserted twice into the hashtable. If a register has
>>> + * ARM_CP_BANKED/ARM_CP_BANKED_64BIT set, it will be inserted twice but 
>>> with
>>> + * different offset respectively. This way Aarch32 registers which can be
>>> + * mapped to Aarch64 PL3 registers can be inserted individually.
>>>  */
>>> #define ARM_CP_SPECIAL 1
>>> #define ARM_CP_CONST 2
>>> @@ -779,16 +878,20 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t 
>>> cpregid)
>>> #define ARM_CP_OVERRIDE 16
>>> #define ARM_CP_NO_MIGRATE 32
>>> #define ARM_CP_IO 64
>>> -#define ARM_CP_NOP (ARM_CP_SPECIAL | (1 << 8))
>>> -#define ARM_CP_WFI (ARM_CP_SPECIAL | (2 << 8))
>>> -#define ARM_CP_NZCV (ARM_CP_SPECIAL | (3 << 8))
>>> -#define ARM_CP_CURRENTEL (ARM_CP_SPECIAL | (4 << 8))
>>> -#define ARM_CP_DC_ZVA (ARM_CP_SPECIAL | (5 << 8))
>>> +#define ARM_CP_SECURE (1 << 7)
>>> +#define ARM_CP_NONSECURE (1 << 8)
>>> +#define ARM_CP_BANKED (ARM_CP_NONSECURE | ARM_CP_SECURE)
>>> +#define ARM_CP_BANKED_64BIT ((1 << 9) | ARM_CP_BANKED)
>>> +#define ARM_CP_NOP (ARM_CP_SPECIAL | (1 << 10))
>>> +#define ARM_CP_WFI (ARM_CP_SPECIAL | (2 << 10))
>>> +#define ARM_CP_NZCV (ARM_CP_SPECIAL | (3 << 10))
>>> +#define ARM_CP_CURRENTEL (ARM_CP_SPECIAL | (4 << 10))
>>> +#define ARM_CP_DC_ZVA (ARM_CP_SPECIAL | (5 << 10))
>>> #define ARM_LAST_SPECIAL ARM_CP_DC_ZVA
>>> /* Used only as a terminator for ARMCPRegInfo lists */
>>> #define ARM_CP_SENTINEL 0xffff
>>> /* Mask of only the flag bits in a type field */
>>> -#define ARM_CP_FLAG_MASK 0x7f
>>> +#define ARM_CP_FLAG_MASK 0x3ff
>>>
>>> /* Valid values for ARMCPRegInfo state field, indicating which of
>>>  * the AArch32 and AArch64 execution states this register is visible in.
>>> diff --git a/target-arm/helper.c b/target-arm/helper.c
>>> index 9326ef8..98c3dc9 100644
>>> --- a/target-arm/helper.c
>>> +++ b/target-arm/helper.c
>>> @@ -2703,7 +2703,7 @@ CpuDefinitionInfoList 
>>> *arch_query_cpu_definitions(Error **errp)
>>>
>>> static void add_cpreg_to_hashtable(ARMCPU *cpu, const ARMCPRegInfo *r,
>>>                                    void *opaque, int state,
>>> -                                   int crm, int opc1, int opc2)
>>> +                                   int crm, int opc1, int opc2, int nsbit)
>>> {
>>>     /* Private utility function for define_one_arm_cp_reg_with_opaque():
>>>      * add a single reginfo struct to the hash table.
>>> @@ -2726,6 +2726,34 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, 
>>> const ARMCPRegInfo *r,
>>>         }
>>> #endif
>>>     }
>>> +
>>> +    if ((r->type & ARM_CP_BANKED) == ARM_CP_BANKED && !nsbit) {
>>> +        if (r2->fieldoffset) {
>>> +            /* We simplify register definitions by providing a type
>>> +             * ARM_CP_BANKED, for which the fieldoffset of the secure 
>>> instance
>>> +             * will be increased to point at the second entry of the array.
>>> +             *
>>> +             * We cannot use is64 or the type ARM_CP_STATE_BOTH to know how
>>> +             * wide the banked register is because some registers are 64bit
>>> +             * wide but the register is not defined as 64bit because it is
>>> +             * mapped to the lower 32 bit.
>>> +             * Therefore two separate types for 64bit banked registers and
>>> +             * 32bit registers are used 
>>> (ARM_CP_BANKED/ARM_CP_BANKED_64BIT).
>>> +             */
>>> +            r2->fieldoffset +=
>>> +                    ((r->type & ARM_CP_BANKED_64BIT) == 
>>> ARM_CP_BANKED_64BIT) ?
>>> +                            sizeof(uint64_t) : sizeof(uint32_t);
>>> +        }
>>> +    }
>>> +    /* For A32 we want to be able to know whether the secure or non-secure
>>> +     * instance wants to be accessed. A64 does not know this banking scheme
>>> +     * anymore, but it might use the same readfn/writefn as A32 which might
>>> +     * rely on it (e.g. in the case of ARM_CP_STATE_BOTH).
>>> +     * Reset the type according to ns-bit passed as argument.
>>> +     */
>>> +    r2->type &= ~(ARM_CP_NONSECURE | ARM_CP_SECURE);
>>> +    r2->type |= nsbit ? ARM_CP_NONSECURE : ARM_CP_SECURE;
>>> +
>>>     if (state == ARM_CP_STATE_AA64) {
>>>         /* To allow abbreviation of ARMCPRegInfo
>>>          * definitions, we treat cp == 0 as equivalent to
>>> @@ -2737,7 +2765,7 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, const 
>>> ARMCPRegInfo *r,
>>>         *key = ENCODE_AA64_CP_REG(r2->cp, r2->crn, crm,
>>>                                   r2->opc0, opc1, opc2);
>>>     } else {
>>> -        *key = ENCODE_CP_REG(r2->cp, is64, r2->crn, crm, opc1, opc2);
>>> +        *key = ENCODE_CP_REG(r2->cp, is64, r2->crn, crm, opc1, opc2, 
>>> nsbit);
>>>     }
>>>     if (opaque) {
>>>         r2->opaque = opaque;
>>> @@ -2773,9 +2801,10 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, 
>>> const ARMCPRegInfo *r,
>>>         oldreg = g_hash_table_lookup(cpu->cp_regs, key);
>>>         if (oldreg && !(oldreg->type & ARM_CP_OVERRIDE)) {
>>>             fprintf(stderr, "Register redefined: cp=%d %d bit "
>>> -                    "crn=%d crm=%d opc1=%d opc2=%d, "
>>> +                    "crn=%d crm=%d opc1=%d opc2=%d ns=%d, "
>>>                     "was %s, now %s\n", r2->cp, 32 + 32 * is64,
>>>                     r2->crn, r2->crm, r2->opc1, r2->opc2,
>>> +                    (r2->type & ARM_CP_NONSECURE),
>>>                     oldreg->name, r2->name);
>>>             g_assert_not_reached();
>>>         }
>>> @@ -2886,8 +2915,33 @@ void define_one_arm_cp_reg_with_opaque(ARMCPU *cpu,
>>>                     if (r->state != state && r->state != ARM_CP_STATE_BOTH) 
>>> {
>>>                         continue;
>>>                     }
>>> -                    add_cpreg_to_hashtable(cpu, r, opaque, state,
>>> -                                           crm, opc1, opc2);
>>> +
>>> +                    if (state == ARM_CP_STATE_AA32) {
>>> +                        if ((r->type & ARM_CP_BANKED) == ARM_CP_BANKED ||
>>> +                                (r->type & ARM_CP_BANKED) == 0) {
>>> +                            /* Under Aarch32 CP registers can be common
>>> +                             * (same for secure and non-secure world) or 
>>> banked.
>>> +                             * Register definitions with neither secure nor
>>> +                             * non-secure type set (common) or with both 
>>> bits
>>> +                             * set (banked) will be inserted twice into the
>>> +                             * hashtable.
>>> +                             */
>>> +                            add_cpreg_to_hashtable(cpu, r, opaque, state,
>>> +                                    crm, opc1, opc2, 0);
>>> +                            add_cpreg_to_hashtable(cpu, r, opaque, state,
>>> +                                    crm, opc1, opc2, 1);
>>> +                        } else {
>>> +                            /* Only one of both bank types were specified 
>>> */
>>> +                            add_cpreg_to_hashtable(cpu, r, opaque, state,
>>> +                                    crm, opc1, opc2,
>>> +                                    (r->type & ARM_CP_NONSECURE) ? 1 : 0);
>>> +                        }
>>> +                    } else {
>>> +                        /* Aarch64 registers get mapped to non-secure 
>>> instance
>>> +                         * of Aarch32 */
>>> +                        add_cpreg_to_hashtable(cpu, r, opaque, state,
>>> +                                crm, opc1, opc2, 1);
>>> +                    }
>>>                 }
>>>             }
>>>         }
>>> diff --git a/target-arm/translate.c b/target-arm/translate.c
>>> index bbd4c77..3a429ac 100644
>>> --- a/target-arm/translate.c
>>> +++ b/target-arm/translate.c
>>> @@ -6866,7 +6866,7 @@ static int disas_neon_data_insn(CPUARMState * env, 
>>> DisasContext *s, uint32_t ins
>>>
>>> static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t 
>>> insn)
>>> {
>>> -    int cpnum, is64, crn, crm, opc1, opc2, isread, rt, rt2;
>>> +    int cpnum, is64, crn, crm, opc1, opc2, isread, rt, rt2, ns;
>>>     const ARMCPRegInfo *ri;
>>>
>>>     cpnum = (insn >> 8) & 0xf;
>>> @@ -6937,8 +6937,11 @@ static int disas_coproc_insn(CPUARMState * env, 
>>> DisasContext *s, uint32_t insn)
>>>     isread = (insn >> 20) & 1;
>>>     rt = (insn >> 12) & 0xf;
>>>
>>> +    /* Monitor mode is always treated as secure but cp register 
>>> reads/writes
>>> +     * can access secure and non-secure instances using SCR.NS bit*/
>>> +    ns = IS_NS(s) ? 1 : !USE_SECURE_REG(env);
>>>     ri = get_arm_cp_reginfo(s->cp_regs,
>>> -                            ENCODE_CP_REG(cpnum, is64, crn, crm, opc1, 
>>> opc2));
>>> +            ENCODE_CP_REG(cpnum, is64, crn, crm, opc1, opc2, ns));
>>>     if (ri) {
>>>         /* Check access permissions */
>>>         if (!cp_access_ok(s->current_pl, ri, isread)) {
>>> @@ -7125,12 +7128,16 @@ static int disas_coproc_insn(CPUARMState * env, 
>>> DisasContext *s, uint32_t insn)
>>>      */
>>>     if (is64) {
>>>         qemu_log_mask(LOG_UNIMP, "%s access to unsupported AArch32 "
>>> -                      "64 bit system register cp:%d opc1: %d crm:%d\n",
>>> -                      isread ? "read" : "write", cpnum, opc1, crm);
>>> +                      "64 bit system register cp:%d opc1: %d crm:%d "
>>> +                      "(%s)\n",
>>> +                      isread ? "read" : "write", cpnum, opc1, crm,
>>> +                      ns ? "non-secure" : "secure");
>>>     } else {
>>>         qemu_log_mask(LOG_UNIMP, "%s access to unsupported AArch32 "
>>> -                      "system register cp:%d opc1:%d crn:%d crm:%d 
>>> opc2:%d\n",
>>> -                      isread ? "read" : "write", cpnum, opc1, crn, crm, 
>>> opc2);
>>> +                      "system register cp:%d opc1:%d crn:%d crm:%d opc2:%d 
>>> "
>>> +                      "(%s)\n",
>>> +                      isread ? "read" : "write", cpnum, opc1, crn, crm, 
>>> opc2,
>>> +                      ns ? "non-secure" : "secure");
>>>     }
>>>
>>>     return 1;
>>> -- 
>>> 1.8.3.2
>>>
>