Hi Connie, On 11/19/25 2:44 PM, Cornelia Huck wrote: > This requires a bit of care, since we still have to handle the EL > specific part (DCZID_EL0.DZP). Callers can set/access dcz_blocksize what do you mean by EL specific part?
you may simply say that at the moment only bs field is handled as part of cpu.dcz_blocklen so you replace all the users of that field by accessors to the isar.idreg[] storage > via a wrapper working on DCZID_EL.BS. > > KVM currently does not support DCZID_EL0 via ONE_REG, and actually > does not need to work with it, so provide a dummy value for now. > > Signed-off-by: Cornelia Huck <[email protected]> > --- > > This is another followup on the ID register rework. The last missing set > of registers are CCSIDR* and friends, then we should be able to switch > to autogenerated registers (probably with a different script than the > last attempt.) > > --- > target/arm/cpu-sysregs.h.inc | 1 + > target/arm/cpu.c | 2 +- > target/arm/cpu.h | 15 +++++++++++++-- > target/arm/cpu64.c | 4 ++-- > target/arm/helper.c | 3 ++- > target/arm/kvm.c | 7 +++++++ > target/arm/tcg/cpu64.c | 22 +++++++++++----------- > target/arm/tcg/helper-a64.c | 2 +- > target/arm/tcg/mte_helper.c | 4 ++-- > target/arm/tcg/translate-a64.c | 2 +- > 10 files changed, 41 insertions(+), 21 deletions(-) > > diff --git a/target/arm/cpu-sysregs.h.inc b/target/arm/cpu-sysregs.h.inc > index 2bb2861c6234..7f3aa8b991aa 100644 > --- a/target/arm/cpu-sysregs.h.inc > +++ b/target/arm/cpu-sysregs.h.inc > @@ -39,3 +39,4 @@ DEF(ID_MMFR5_EL1, 3, 0, 0, 3, 6) > DEF(CLIDR_EL1, 3, 1, 0, 0, 1) > DEF(ID_AA64ZFR0_EL1, 3, 0, 0, 4, 4) > DEF(CTR_EL0, 3, 3, 0, 0, 1) > +DEF(DCZID_EL0, 3, 3, 0, 0, 7) > diff --git a/target/arm/cpu.c b/target/arm/cpu.c > index 39292fb9bc1f..ad99233839c0 100644 > --- a/target/arm/cpu.c > +++ b/target/arm/cpu.c > @@ -2184,7 +2184,7 @@ static void arm_cpu_realizefn(DeviceState *dev, Error > **errp) > #endif > > if (tcg_enabled()) { > - int dcz_blocklen = 4 << cpu->dcz_blocksize; > + int dcz_blocklen = 4 << get_dcz_blocksize(cpu); > > /* > * We only support DCZ blocklen that fits on one page. > diff --git a/target/arm/cpu.h b/target/arm/cpu.h > index 39f2b2e54deb..e3fa6ebda3f2 100644 > --- a/target/arm/cpu.h > +++ b/target/arm/cpu.h > @@ -1111,8 +1111,6 @@ struct ArchCPU { > bool prop_pauth_qarma5; > bool prop_lpa2; > > - /* DCZ blocksize, in log_2(words), ie low 4 bits of DCZID_EL0 */ > - uint8_t dcz_blocksize; > /* GM blocksize, in log_2(words), ie low 4 bits of GMID_EL0 */ > uint8_t gm_blocksize; > > @@ -1178,6 +1176,19 @@ struct ARMCPUClass { > ResettablePhases parent_phases; > }; > > +static inline uint8_t get_dcz_blocksize(ARMCPU *cpu) While at it I would replace dcz_blocksize by dczid_el0_bs to be more explicit > +{ > + return cpu->isar.idregs[DCZID_EL0_IDX] & 0xf; extract64? > +} > + > +static inline void set_dcz_blocksize(ARMCPU *cpu, uint8_t bs) > +{ > + uint64_t dczid = cpu->isar.idregs[DCZID_EL0_IDX]; > + > + /* keep dzp unchanged */ > + cpu->isar.idregs[DCZID_EL0_IDX] = (dczid & ~0xf) | bs; deposit64? > +} > + > /* Callback functions for the generic timer's timers. */ > void arm_gt_ptimer_cb(void *opaque); > void arm_gt_vtimer_cb(void *opaque); > diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c > index ae84d8e42050..23924f251020 100644 > --- a/target/arm/cpu64.c > +++ b/target/arm/cpu64.c > @@ -689,7 +689,7 @@ static void aarch64_a57_initfn(Object *obj) > cpu->ccsidr[1] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 3, 64, 48 * KiB, 2); > /* 2048KB L2 cache */ > cpu->ccsidr[2] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 16, 64, 2 * MiB, 7); > - cpu->dcz_blocksize = 4; /* 64 bytes */ > + set_dcz_blocksize(cpu, 4); /* 64 bytes */ > cpu->gic_num_lrs = 4; > cpu->gic_vpribits = 5; > cpu->gic_vprebits = 5; > @@ -751,7 +751,7 @@ static void aarch64_a53_initfn(Object *obj) > cpu->ccsidr[1] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 1, 64, 32 * KiB, 2); > /* 1024KB L2 cache */ > cpu->ccsidr[2] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 16, 64, 1 * MiB, 7); > - cpu->dcz_blocksize = 4; /* 64 bytes */ > + set_dcz_blocksize(cpu, 4); /* 64 bytes */ > cpu->gic_num_lrs = 4; > cpu->gic_vpribits = 5; > cpu->gic_vprebits = 5; > diff --git a/target/arm/helper.c b/target/arm/helper.c > index 27ebc6f29b82..8dfeaff25350 100644 > --- a/target/arm/helper.c > +++ b/target/arm/helper.c > @@ -3324,7 +3324,8 @@ static uint64_t aa64_dczid_read(CPUARMState *env, const > ARMCPRegInfo *ri) the name of the function seems to indicate you read the whole DCZID but I see the DZP bit is tweaked below. Do you get why we can't return the raw id reg? > if (aa64_zva_access(env, NULL, false) == CP_ACCESS_OK) { > dzp_bit = 0; > } > - return cpu->dcz_blocksize | dzp_bit; > + nit spurious NL > + return cpu->isar.idregs[DCZID_EL0_IDX] | dzp_bit; > } > > static CPAccessResult sp_el0_access(CPUARMState *env, const ARMCPRegInfo *ri, > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > index 0d57081e69fb..5d65f64addc6 100644 > --- a/target/arm/kvm.c > +++ b/target/arm/kvm.c > @@ -2020,6 +2020,13 @@ int kvm_arch_init_vcpu(CPUState *cs) > } > cpu->mp_affinity = mpidr & ARM64_AFFINITY_MASK; > > + /* > + * We currently do not need this, except for tcg. Should KVM gain support > + * for accessing DCZID_EL0 via ONE_REG, we'll overwrite this below. Just > + * set a dummy value that corresponds to the minimum value for FEAT_MTE2. > + */ > + set_dcz_blocksize(cpu, 2); it is not clear to me why we need that? > + > return kvm_arm_init_cpreg_list(cpu); > } > > diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c > index 6871956382f7..d86fc38e7157 100644 > --- a/target/arm/tcg/cpu64.c > +++ b/target/arm/tcg/cpu64.c > @@ -72,7 +72,7 @@ static void aarch64_a35_initfn(Object *obj) > SET_IDREG(isar, ID_AA64MMFR0, 0x00101122); > SET_IDREG(isar, ID_AA64MMFR1, 0); > SET_IDREG(isar, CLIDR, 0x0a200023); > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > > /* From B2.4 AArch64 Virtual Memory control registers */ > cpu->reset_sctlr = 0x00c50838; > @@ -219,7 +219,7 @@ static void aarch64_a55_initfn(Object *obj) > /* Ordered by B2.4 AArch64 registers by functional group */ > SET_IDREG(isar, CLIDR, 0x82000023); > cpu->ctr = 0x84448004; /* L1Ip = VIPT */ > - cpu->dcz_blocksize = 4; /* 64 bytes */ > + set_dcz_blocksize(cpu, 4); /* 64 bytes */ > SET_IDREG(isar, ID_AA64DFR0, 0x0000000010305408ull); > SET_IDREG(isar, ID_AA64ISAR0, 0x0000100010211120ull); > SET_IDREG(isar, ID_AA64ISAR1, 0x0000000000100001ull); > @@ -325,7 +325,7 @@ static void aarch64_a72_initfn(Object *obj) > cpu->ccsidr[1] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 3, 64, 48 * KiB, 2); > /* 1MB L2 cache */ > cpu->ccsidr[2] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 16, 64, 1 * MiB, 7); > - cpu->dcz_blocksize = 4; /* 64 bytes */ > + set_dcz_blocksize(cpu, 4); /* 64 bytes */ > cpu->gic_num_lrs = 4; > cpu->gic_vpribits = 5; > cpu->gic_vprebits = 5; > @@ -352,7 +352,7 @@ static void aarch64_a76_initfn(Object *obj) > /* Ordered by B2.4 AArch64 registers by functional group */ > SET_IDREG(isar, CLIDR, 0x82000023); > cpu->ctr = 0x8444C004; > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > SET_IDREG(isar, ID_AA64DFR0, 0x0000000010305408ull); > SET_IDREG(isar, ID_AA64ISAR0, 0x0000100010211120ull); > SET_IDREG(isar, ID_AA64ISAR1, 0x0000000000100001ull); > @@ -424,7 +424,7 @@ static void aarch64_a78ae_initfn(Object *obj) > /* Ordered by 3.2.4 AArch64 registers by functional group */ > SET_IDREG(isar, CLIDR, 0x82000023); > cpu->ctr = 0x9444c004; > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > SET_IDREG(isar, ID_AA64DFR0, 0x0000000110305408ull); > SET_IDREG(isar, ID_AA64ISAR0, 0x0010100010211120ull); > SET_IDREG(isar, ID_AA64ISAR1, 0x0000000001200031ull); > @@ -517,7 +517,7 @@ static void aarch64_a64fx_initfn(Object *obj) > cpu->ccsidr[1] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 4, 256, 64 * KiB, 2); > /* 8MB L2 cache */ > cpu->ccsidr[2] = make_ccsidr(CCSIDR_FORMAT_LEGACY, 16, 256, 8 * MiB, 7); > - cpu->dcz_blocksize = 6; /* 256 bytes */ > + set_dcz_blocksize(cpu, 6); /* 256 bytes */ > cpu->gic_num_lrs = 4; > cpu->gic_vpribits = 5; > cpu->gic_vprebits = 5; > @@ -673,7 +673,7 @@ static void aarch64_neoverse_n1_initfn(Object *obj) > /* Ordered by B2.4 AArch64 registers by functional group */ > SET_IDREG(isar, CLIDR, 0x82000023); > cpu->ctr = 0x8444c004; > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > SET_IDREG(isar, ID_AA64DFR0, 0x0000000110305408ull); > SET_IDREG(isar, ID_AA64ISAR0, 0x0000100010211120ull); > SET_IDREG(isar, ID_AA64ISAR1, 0x0000000000100001ull); > @@ -749,7 +749,7 @@ static void aarch64_neoverse_v1_initfn(Object *obj) > /* Ordered by 3.2.4 AArch64 registers by functional group */ > SET_IDREG(isar, CLIDR, 0x82000023); > cpu->ctr = 0xb444c004; /* With DIC and IDC set */ > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > SET_IDREG(isar, ID_AA64AFR0, 0x00000000); > SET_IDREG(isar, ID_AA64AFR1, 0x00000000); > SET_IDREG(isar, ID_AA64DFR0, 0x000001f210305519ull); > @@ -1011,7 +1011,7 @@ static void aarch64_a710_initfn(Object *obj) > SET_IDREG(isar, CLIDR, 0x0000001482000023ull); > cpu->gm_blocksize = 4; > cpu->ctr = 0x000000049444c004ull; > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > /* TODO FEAT_MPAM: mpamidr_el1 = 0x0000_0001_0006_003f */ > > /* Section B.5.2: PMCR_EL0 */ > @@ -1113,7 +1113,7 @@ static void aarch64_neoverse_n2_initfn(Object *obj) > SET_IDREG(isar, CLIDR, 0x0000001482000023ull); > cpu->gm_blocksize = 4; > cpu->ctr = 0x00000004b444c004ull; > - cpu->dcz_blocksize = 4; > + set_dcz_blocksize(cpu, 4); > /* TODO FEAT_MPAM: mpamidr_el1 = 0x0000_0001_001e_01ff */ > > /* Section B.7.2: PMCR_EL0 */ > @@ -1377,7 +1377,7 @@ void aarch64_max_tcg_initfn(Object *obj) > * blocksize since we don't have to follow what the hardware does. > */ > cpu->ctr = 0x80038003; /* 32 byte I and D cacheline size, VIPT icache */ > - cpu->dcz_blocksize = 7; /* 512 bytes */ > + set_dcz_blocksize(cpu, 7); /* 512 bytes */ > #endif > cpu->gm_blocksize = 6; /* 256 bytes */ > > diff --git a/target/arm/tcg/helper-a64.c b/target/arm/tcg/helper-a64.c > index ba1d775d818e..045a00b43373 100644 > --- a/target/arm/tcg/helper-a64.c > +++ b/target/arm/tcg/helper-a64.c > @@ -792,7 +792,7 @@ void HELPER(dc_zva)(CPUARMState *env, uint64_t vaddr_in) > * (which matches the usual QEMU behaviour of not implementing either > * alignment faults or any memory attribute handling). > */ > - int blocklen = 4 << env_archcpu(env)->dcz_blocksize; > + int blocklen = 4 << get_dcz_blocksize(env_archcpu(env)); > uint64_t vaddr = vaddr_in & ~(blocklen - 1); > int mmu_idx = arm_env_mmu_index(env); > void *mem; > diff --git a/target/arm/tcg/mte_helper.c b/target/arm/tcg/mte_helper.c > index bb48fe359b8c..20f8351d8676 100644 > --- a/target/arm/tcg/mte_helper.c > +++ b/target/arm/tcg/mte_helper.c > @@ -545,7 +545,7 @@ void HELPER(stzgm_tags)(CPUARMState *env, uint64_t ptr, > uint64_t val) > * i.e. 32 bytes, which is an unreasonably small dcz anyway, > * to make sure that we can access one complete tag byte here. > */ > - log2_dcz_bytes = env_archcpu(env)->dcz_blocksize + 2; > + log2_dcz_bytes = get_dcz_blocksize(env_archcpu(env)) + 2; > log2_tag_bytes = log2_dcz_bytes - (LOG2_TAG_GRANULE + 1); > dcz_bytes = (intptr_t)1 << log2_dcz_bytes; > tag_bytes = (intptr_t)1 << log2_tag_bytes; > @@ -945,7 +945,7 @@ uint64_t HELPER(mte_check_zva)(CPUARMState *env, uint32_t > desc, uint64_t ptr) > * i.e. 32 bytes, which is an unreasonably small dcz anyway, to make > * sure that we can access one complete tag byte here. > */ > - log2_dcz_bytes = env_archcpu(env)->dcz_blocksize + 2; > + log2_dcz_bytes = get_dcz_blocksize(env_archcpu(env)) + 2; > log2_tag_bytes = log2_dcz_bytes - (LOG2_TAG_GRANULE + 1); > dcz_bytes = (intptr_t)1 << log2_dcz_bytes; > tag_bytes = (intptr_t)1 << log2_tag_bytes; > diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c > index 08b21d7dbfa6..c72611e55e45 100644 > --- a/target/arm/tcg/translate-a64.c > +++ b/target/arm/tcg/translate-a64.c > @@ -10712,7 +10712,7 @@ static void > aarch64_tr_init_disas_context(DisasContextBase *dcbase, > dc->vec_stride = 0; > dc->cp_regs = arm_cpu->cp_regs; > dc->features = env->features; > - dc->dcz_blocksize = arm_cpu->dcz_blocksize; > + dc->dcz_blocksize = get_dcz_blocksize(arm_cpu); > dc->gm_blocksize = arm_cpu->gm_blocksize; > > #ifdef CONFIG_USER_ONLY Thanks Eric
