| Message ID | 20220209124135.69183-1-agraf@csgraf.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/2] hvf: arm: Use macros for sysreg shift/masking | expand |
LGTM Reviewed-by: Cameron Esfahani <dirty@apple.com <mailto:dirty@apple.com>> Cameron > On Feb 9, 2022, at 4:41 AM, Alexander Graf <agraf@csgraf.de> wrote: > > We are parsing the syndrome field for sysregs in multiple places across > the hvf code, but repeat shift/mask operations with hard coded constants > every time. This is an error prone approach and makes it harder to reason > about the correctness of these operations. > > Let's introduce macros that allow us to unify the constants used as well > as create new helpers to extract fields from the sysreg value. > > Suggested-by: Peter Maydell <peter.maydell@linaro.org> > Signed-off-by: Alexander Graf <agraf@csgraf.de> > --- > target/arm/hvf/hvf.c | 69 ++++++++++++++++++++++++++++++-------------- > 1 file changed, 47 insertions(+), 22 deletions(-) > > diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c > index 92ad0d29c4..8d0447ab01 100644 > --- a/target/arm/hvf/hvf.c > +++ b/target/arm/hvf/hvf.c > @@ -35,9 +35,34 @@ > ENCODE_AA64_CP_REG(CP_REG_ARM64_SYSREG_CP, crn, crm, op0, op1, op2) > #define PL1_WRITE_MASK 0x4 > > +#define SYSREG_OP0_SHIFT 20 > +#define SYSREG_OP0_MASK 0x3 > +#define SYSREG_OP0(sysreg) ((sysreg >> SYSREG_OP0_SHIFT) & SYSREG_OP0_MASK) > +#define SYSREG_OP1_SHIFT 14 > +#define SYSREG_OP1_MASK 0x7 > +#define SYSREG_OP1(sysreg) ((sysreg >> SYSREG_OP1_SHIFT) & SYSREG_OP1_MASK) > +#define SYSREG_CRN_SHIFT 10 > +#define SYSREG_CRN_MASK 0xf > +#define SYSREG_CRN(sysreg) ((sysreg >> SYSREG_CRN_SHIFT) & SYSREG_CRN_MASK) > +#define SYSREG_CRM_SHIFT 1 > +#define SYSREG_CRM_MASK 0xf > +#define SYSREG_CRM(sysreg) ((sysreg >> SYSREG_CRM_SHIFT) & SYSREG_CRM_MASK) > +#define SYSREG_OP2_SHIFT 17 > +#define SYSREG_OP2_MASK 0x7 > +#define SYSREG_OP2(sysreg) ((sysreg >> SYSREG_OP2_SHIFT) & SYSREG_OP2_MASK) > + > #define SYSREG(op0, op1, crn, crm, op2) \ > - ((op0 << 20) | (op2 << 17) | (op1 << 14) | (crn << 10) | (crm << 1)) > -#define SYSREG_MASK SYSREG(0x3, 0x7, 0xf, 0xf, 0x7) > + ((op0 << SYSREG_OP0_SHIFT) | \ > + (op1 << SYSREG_OP1_SHIFT) | \ > + (crn << SYSREG_CRN_SHIFT) | \ > + (crm << SYSREG_CRM_SHIFT) | \ > + (op2 << SYSREG_OP2_SHIFT)) > +#define SYSREG_MASK \ > + SYSREG(SYSREG_OP0_MASK, \ > + SYSREG_OP1_MASK, \ > + SYSREG_CRN_MASK, \ > + SYSREG_CRM_MASK, \ > + SYSREG_OP2_MASK) > #define SYSREG_OSLAR_EL1 SYSREG(2, 0, 1, 0, 4) > #define SYSREG_OSLSR_EL1 SYSREG(2, 0, 1, 1, 4) > #define SYSREG_OSDLR_EL1 SYSREG(2, 0, 1, 3, 4) > @@ -783,21 +808,21 @@ static int hvf_sysreg_read(CPUState *cpu, uint32_t reg, uint32_t rt) > default: > cpu_synchronize_state(cpu); > trace_hvf_unhandled_sysreg_read(env->pc, reg, > - (reg >> 20) & 0x3, > - (reg >> 14) & 0x7, > - (reg >> 10) & 0xf, > - (reg >> 1) & 0xf, > - (reg >> 17) & 0x7); > + SYSREG_OP0(reg), > + SYSREG_OP1(reg), > + SYSREG_CRN(reg), > + SYSREG_CRM(reg), > + SYSREG_OP2(reg)); > hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized()); > return 1; > } > > trace_hvf_sysreg_read(reg, > - (reg >> 20) & 0x3, > - (reg >> 14) & 0x7, > - (reg >> 10) & 0xf, > - (reg >> 1) & 0xf, > - (reg >> 17) & 0x7, > + SYSREG_OP0(reg), > + SYSREG_OP1(reg), > + SYSREG_CRN(reg), > + SYSREG_CRM(reg), > + SYSREG_OP2(reg), > val); > hvf_set_reg(cpu, rt, val); > > @@ -886,11 +911,11 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val) > CPUARMState *env = &arm_cpu->env; > > trace_hvf_sysreg_write(reg, > - (reg >> 20) & 0x3, > - (reg >> 14) & 0x7, > - (reg >> 10) & 0xf, > - (reg >> 1) & 0xf, > - (reg >> 17) & 0x7, > + SYSREG_OP0(reg), > + SYSREG_OP1(reg), > + SYSREG_CRN(reg), > + SYSREG_CRM(reg), > + SYSREG_OP2(reg), > val); > > switch (reg) { > @@ -960,11 +985,11 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val) > default: > cpu_synchronize_state(cpu); > trace_hvf_unhandled_sysreg_write(env->pc, reg, > - (reg >> 20) & 0x3, > - (reg >> 14) & 0x7, > - (reg >> 10) & 0xf, > - (reg >> 1) & 0xf, > - (reg >> 17) & 0x7); > + SYSREG_OP0(reg), > + SYSREG_OP1(reg), > + SYSREG_CRN(reg), > + SYSREG_CRM(reg), > + SYSREG_OP2(reg)); > hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized()); > return 1; > } > -- > 2.32.0 (Apple Git-132) >
On 9/2/22 13:41, Alexander Graf wrote: > We are parsing the syndrome field for sysregs in multiple places across > the hvf code, but repeat shift/mask operations with hard coded constants > every time. This is an error prone approach and makes it harder to reason > about the correctness of these operations. > > Let's introduce macros that allow us to unify the constants used as well > as create new helpers to extract fields from the sysreg value. > > Suggested-by: Peter Maydell <peter.maydell@linaro.org> > Signed-off-by: Alexander Graf <agraf@csgraf.de> > --- > target/arm/hvf/hvf.c | 69 ++++++++++++++++++++++++++++++-------------- > 1 file changed, 47 insertions(+), 22 deletions(-) > > diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c > index 92ad0d29c4..8d0447ab01 100644 > --- a/target/arm/hvf/hvf.c > +++ b/target/arm/hvf/hvf.c > @@ -35,9 +35,34 @@ > ENCODE_AA64_CP_REG(CP_REG_ARM64_SYSREG_CP, crn, crm, op0, op1, op2) > #define PL1_WRITE_MASK 0x4 > > +#define SYSREG_OP0_SHIFT 20 > +#define SYSREG_OP0_MASK 0x3 > +#define SYSREG_OP0(sysreg) ((sysreg >> SYSREG_OP0_SHIFT) & SYSREG_OP0_MASK) > +#define SYSREG_OP1_SHIFT 14 > +#define SYSREG_OP1_MASK 0x7 > +#define SYSREG_OP1(sysreg) ((sysreg >> SYSREG_OP1_SHIFT) & SYSREG_OP1_MASK) > +#define SYSREG_CRN_SHIFT 10 > +#define SYSREG_CRN_MASK 0xf > +#define SYSREG_CRN(sysreg) ((sysreg >> SYSREG_CRN_SHIFT) & SYSREG_CRN_MASK) > +#define SYSREG_CRM_SHIFT 1 > +#define SYSREG_CRM_MASK 0xf > +#define SYSREG_CRM(sysreg) ((sysreg >> SYSREG_CRM_SHIFT) & SYSREG_CRM_MASK) > +#define SYSREG_OP2_SHIFT 17 > +#define SYSREG_OP2_MASK 0x7 > +#define SYSREG_OP2(sysreg) ((sysreg >> SYSREG_OP2_SHIFT) & SYSREG_OP2_MASK) Alternatively easier to read using the "hw/registerfields.h" macros: FIELD(SYSREG, OP0, 20, 2) FIELD(SYSREG, OP2, 17, 3) FIELD(SYSREG, OP1, 14, 3) FIELD(SYSREG, CRN, 10, 4) FIELD(SYSREG, CRM, 1, 4) Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
On Wed, 9 Feb 2022 at 12:41, Alexander Graf <agraf@csgraf.de> wrote: > > We are parsing the syndrome field for sysregs in multiple places across > the hvf code, but repeat shift/mask operations with hard coded constants > every time. This is an error prone approach and makes it harder to reason > about the correctness of these operations. > > Let's introduce macros that allow us to unify the constants used as well > as create new helpers to extract fields from the sysreg value. > > Suggested-by: Peter Maydell <peter.maydell@linaro.org> > Signed-off-by: Alexander Graf <agraf@csgraf.de> Applied this and patch 2/2 to target-arm.next, thanks. (If you can send multi-patch sets with a cover letter that helps the automated tools, by the way.) -- PMM
diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c index 92ad0d29c4..8d0447ab01 100644 --- a/target/arm/hvf/hvf.c +++ b/target/arm/hvf/hvf.c @@ -35,9 +35,34 @@ ENCODE_AA64_CP_REG(CP_REG_ARM64_SYSREG_CP, crn, crm, op0, op1, op2) #define PL1_WRITE_MASK 0x4 +#define SYSREG_OP0_SHIFT 20 +#define SYSREG_OP0_MASK 0x3 +#define SYSREG_OP0(sysreg) ((sysreg >> SYSREG_OP0_SHIFT) & SYSREG_OP0_MASK) +#define SYSREG_OP1_SHIFT 14 +#define SYSREG_OP1_MASK 0x7 +#define SYSREG_OP1(sysreg) ((sysreg >> SYSREG_OP1_SHIFT) & SYSREG_OP1_MASK) +#define SYSREG_CRN_SHIFT 10 +#define SYSREG_CRN_MASK 0xf +#define SYSREG_CRN(sysreg) ((sysreg >> SYSREG_CRN_SHIFT) & SYSREG_CRN_MASK) +#define SYSREG_CRM_SHIFT 1 +#define SYSREG_CRM_MASK 0xf +#define SYSREG_CRM(sysreg) ((sysreg >> SYSREG_CRM_SHIFT) & SYSREG_CRM_MASK) +#define SYSREG_OP2_SHIFT 17 +#define SYSREG_OP2_MASK 0x7 +#define SYSREG_OP2(sysreg) ((sysreg >> SYSREG_OP2_SHIFT) & SYSREG_OP2_MASK) + #define SYSREG(op0, op1, crn, crm, op2) \ - ((op0 << 20) | (op2 << 17) | (op1 << 14) | (crn << 10) | (crm << 1)) -#define SYSREG_MASK SYSREG(0x3, 0x7, 0xf, 0xf, 0x7) + ((op0 << SYSREG_OP0_SHIFT) | \ + (op1 << SYSREG_OP1_SHIFT) | \ + (crn << SYSREG_CRN_SHIFT) | \ + (crm << SYSREG_CRM_SHIFT) | \ + (op2 << SYSREG_OP2_SHIFT)) +#define SYSREG_MASK \ + SYSREG(SYSREG_OP0_MASK, \ + SYSREG_OP1_MASK, \ + SYSREG_CRN_MASK, \ + SYSREG_CRM_MASK, \ + SYSREG_OP2_MASK) #define SYSREG_OSLAR_EL1 SYSREG(2, 0, 1, 0, 4) #define SYSREG_OSLSR_EL1 SYSREG(2, 0, 1, 1, 4) #define SYSREG_OSDLR_EL1 SYSREG(2, 0, 1, 3, 4) @@ -783,21 +808,21 @@ static int hvf_sysreg_read(CPUState *cpu, uint32_t reg, uint32_t rt) default: cpu_synchronize_state(cpu); trace_hvf_unhandled_sysreg_read(env->pc, reg, - (reg >> 20) & 0x3, - (reg >> 14) & 0x7, - (reg >> 10) & 0xf, - (reg >> 1) & 0xf, - (reg >> 17) & 0x7); + SYSREG_OP0(reg), + SYSREG_OP1(reg), + SYSREG_CRN(reg), + SYSREG_CRM(reg), + SYSREG_OP2(reg)); hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized()); return 1; } trace_hvf_sysreg_read(reg, - (reg >> 20) & 0x3, - (reg >> 14) & 0x7, - (reg >> 10) & 0xf, - (reg >> 1) & 0xf, - (reg >> 17) & 0x7, + SYSREG_OP0(reg), + SYSREG_OP1(reg), + SYSREG_CRN(reg), + SYSREG_CRM(reg), + SYSREG_OP2(reg), val); hvf_set_reg(cpu, rt, val); @@ -886,11 +911,11 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val) CPUARMState *env = &arm_cpu->env; trace_hvf_sysreg_write(reg, - (reg >> 20) & 0x3, - (reg >> 14) & 0x7, - (reg >> 10) & 0xf, - (reg >> 1) & 0xf, - (reg >> 17) & 0x7, + SYSREG_OP0(reg), + SYSREG_OP1(reg), + SYSREG_CRN(reg), + SYSREG_CRM(reg), + SYSREG_OP2(reg), val); switch (reg) { @@ -960,11 +985,11 @@ static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val) default: cpu_synchronize_state(cpu); trace_hvf_unhandled_sysreg_write(env->pc, reg, - (reg >> 20) & 0x3, - (reg >> 14) & 0x7, - (reg >> 10) & 0xf, - (reg >> 1) & 0xf, - (reg >> 17) & 0x7); + SYSREG_OP0(reg), + SYSREG_OP1(reg), + SYSREG_CRN(reg), + SYSREG_CRM(reg), + SYSREG_OP2(reg)); hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized()); return 1; }
We are parsing the syndrome field for sysregs in multiple places across the hvf code, but repeat shift/mask operations with hard coded constants every time. This is an error prone approach and makes it harder to reason about the correctness of these operations. Let's introduce macros that allow us to unify the constants used as well as create new helpers to extract fields from the sysreg value. Suggested-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Alexander Graf <agraf@csgraf.de> --- target/arm/hvf/hvf.c | 69 ++++++++++++++++++++++++++++++-------------- 1 file changed, 47 insertions(+), 22 deletions(-)