Re: [Qemu-devel] [PATCH v1 07/16] target-arm: Add HCR_EL2

["Alex Bennée" <alex.bennee@linaro.org>]

Edgar E. Iglesias writes:

> From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
>
> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
> ---
>  target-arm/cpu.h    | 35 +++++++++++++++++++++++++++++++++++
>  target-arm/helper.c | 27 +++++++++++++++++++++++++++
>  2 files changed, 62 insertions(+)
>
> diff --git a/target-arm/cpu.h b/target-arm/cpu.h
> index ef6a95d..b446478 100644
> --- a/target-arm/cpu.h
> +++ b/target-arm/cpu.h
> @@ -184,6 +184,7 @@ typedef struct CPUARMState {
>                          MPU write buffer control.  */
>          uint32_t pmsav5_data_ap; /* PMSAv5 MPU data access permissions */
>          uint32_t pmsav5_insn_ap; /* PMSAv5 MPU insn access permissions */
> +        uint64_t hcr_el2; /* Hypervisor configuration register */
>          uint32_t ifsr_el2; /* Fault status registers.  */
>          uint64_t esr_el[4];
>          uint32_t c6_region[8]; /* MPU base/size registers.  */
> @@ -526,6 +527,40 @@ static inline void xpsr_write(CPUARMState *env, uint32_t val, uint32_t mask)
>      }
>  }
>  
> +#define HCR_VM        (1ULL << 0)
> +#define HCR_SWIO      (1ULL << 1)
> +#define HCR_PTW       (1ULL << 2)
> +#define HCR_FMO       (1ULL << 3)
> +#define HCR_IMO       (1ULL << 4)
> +#define HCR_AMO       (1ULL << 5)
> +#define HCR_VF        (1ULL << 6)
> +#define HCR_VI        (1ULL << 7)
> +#define HCR_VSE       (1ULL << 8)
> +#define HCR_FB        (1ULL << 9)
> +#define HCR_DC        (1ULL << 12)
> +#define HCR_TWI       (1ULL << 13)
> +#define HCR_TWE       (1ULL << 14)
> +#define HCR_TID0      (1ULL << 15)
> +#define HCR_TID1      (1ULL << 16)
> +#define HCR_TID2      (1ULL << 17)
> +#define HCR_TID3      (1ULL << 18)
> +#define HCR_TSC       (1ULL << 19)
> +#define HCR_TIDCP     (1ULL << 20)
> +#define HCR_TACR      (1ULL << 21)
> +#define HCR_TSW       (1ULL << 22)
> +#define HCR_TPC       (1ULL << 23)
> +#define HCR_TPU       (1ULL << 24)
> +#define HCR_TTLB      (1ULL << 25)
> +#define HCR_TVM       (1ULL << 26)
> +#define HCR_TGE       (1ULL << 27)
> +#define HCR_TDZ       (1ULL << 28)
> +#define HCR_HCD       (1ULL << 29)
> +#define HCR_TRVM      (1ULL << 30)
> +#define HCR_RW        (1ULL << 31)
> +#define HCR_CD        (1ULL << 32)
> +#define HCR_ID        (1ULL << 33)
> +#define HCR_RES0_MASK ((1ULL << 34) - 1)

Hmm isn't that actually HCR_MASK? I would expect the mask for the RES0
bits to be ~((1ULL << 34) - 1) but it's not actually used for that hence
the name confusion.

> +
>  /* Return the current FPSCR value.  */
>  uint32_t vfp_get_fpscr(CPUARMState *env);
>  void vfp_set_fpscr(CPUARMState *env, uint32_t val);
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index de5ee40..cf877ae 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -2107,10 +2107,37 @@ static const ARMCPRegInfo v8_el3_no_el2_cp_reginfo[] = {
>        .opc0 = 3, .opc1 = 4, .crn = 12, .crm = 0, .opc2 = 0,
>        .access = PL2_RW,
>        .readfn = arm_cp_read_zero, .writefn = arm_cp_write_ignore },
> +    { .name = "HCR_EL2", .state = ARM_CP_STATE_AA64,
> +      .type = ARM_CP_NO_MIGRATE,
> +      .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 0,
> +      .readfn = arm_cp_read_zero, .writefn = arm_cp_write_ignore },
>      REGINFO_SENTINEL
>  };
>  
> +static void hcr_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value)
> +{
> +    ARMCPU *cpu = arm_env_get_cpu(env);
> +    uint64_t res0_mask = HCR_RES0_MASK;
> +
> +    if (!arm_feature(env, ARM_FEATURE_EL3)) {
> +        res0_mask &= ~HCR_HCD;
> +    }
> +
> +    /* Clear RES0 bits.  */
> +    value &= res0_mask;
> +
> +    if ((raw_read(env, ri) ^ value) & HCR_VM) {
> +        /* Flush the TLB when turning VM on/off.  */
> +        tlb_flush(CPU(cpu), 1);
> +    }
> +    raw_write(env, ri, value);
> +}
> +
>  static const ARMCPRegInfo v8_el2_cp_reginfo[] = {
> +    { .name = "HCR_EL2", .state = ARM_CP_STATE_AA64,
> +      .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 0,
> +      .access = PL2_RW, .fieldoffset = offsetof(CPUARMState, cp15.hcr_el2),
> +      .writefn = hcr_write },
>      { .name = "ELR_EL2", .state = ARM_CP_STATE_AA64,
>        .type = ARM_CP_NO_MIGRATE,
>        .opc0 = 3, .opc1 = 4, .crn = 4, .crm = 0, .opc2 = 1,

-- 
Alex Bennée