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

[Sergey Fedorov <serge.fdrv@gmail.com>]

13.05.2014 20:15, Fabian Aggeler wrote:
> @@ -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.
>   */

I think it could be done with just adding a single flag indicating that
NS tag of reginfo should be considered, otherwise insert reginfo into
the hashtable twice.
In order to distinguish 64 bit register, there is already ARM_CP_64BIT
macro defined.

Regards,
Sergey

>  #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.