On Wed, Jun 28, 2023 at 06:30:24PM -0300, Daniel Henrique Barboza wrote: > Next patch will add KVM specific user properties for both MISA and > multi-letter extensions. For MISA extensions we want to make use of what > is already available in misa_ext_cfgs[] to avoid code repetition. > > misa_ext_info_arr[] array will hold name and description for each MISA > extension that misa_ext_cfgs[] is declaring. We'll then use this new > array in KVM code to avoid duplicating strings. > > There's nothing holding us back from doing the same with multi-letter > extensions. For now doing just with MISA extensions is enough. > > Suggested-by: Andrew Jones <ajo...@ventanamicro.com> > Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com> > --- > target/riscv/cpu.c | 83 ++++++++++++++++++++++++++++++---------------- > target/riscv/cpu.h | 7 +++- > 2 files changed, 61 insertions(+), 29 deletions(-) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index 2485e820f8..90dd2078ae 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -1558,33 +1558,57 @@ static void cpu_get_misa_ext_cfg(Object *obj, Visitor > *v, const char *name, > visit_type_bool(v, name, &value, errp); > } > > -static const RISCVCPUMisaExtConfig misa_ext_cfgs[] = { > - {.name = "a", .description = "Atomic instructions", > - .misa_bit = RVA, .enabled = true}, > - {.name = "c", .description = "Compressed instructions", > - .misa_bit = RVC, .enabled = true}, > - {.name = "d", .description = "Double-precision float point", > - .misa_bit = RVD, .enabled = true}, > - {.name = "f", .description = "Single-precision float point", > - .misa_bit = RVF, .enabled = true}, > - {.name = "i", .description = "Base integer instruction set", > - .misa_bit = RVI, .enabled = true}, > - {.name = "e", .description = "Base integer instruction set (embedded)", > - .misa_bit = RVE, .enabled = false}, > - {.name = "m", .description = "Integer multiplication and division", > - .misa_bit = RVM, .enabled = true}, > - {.name = "s", .description = "Supervisor-level instructions", > - .misa_bit = RVS, .enabled = true}, > - {.name = "u", .description = "User-level instructions", > - .misa_bit = RVU, .enabled = true}, > - {.name = "h", .description = "Hypervisor", > - .misa_bit = RVH, .enabled = true}, > - {.name = "x-j", .description = "Dynamic translated languages", > - .misa_bit = RVJ, .enabled = false}, > - {.name = "v", .description = "Vector operations", > - .misa_bit = RVV, .enabled = false}, > - {.name = "g", .description = "General purpose (IMAFD_Zicsr_Zifencei)", > - .misa_bit = RVG, .enabled = false}, > +typedef struct misa_ext_info { > + const char *name; > + const char *description; > +} MISAExtInfo; > + > +#define MISA_EXT_INFO(_idx, _propname, _descr) \ > + [(_idx - 'A')] = {.name = _propname, .description = _descr}
We don't have to give up on passing RV* to this macro. Directly using __builtin_ctz() with a constant should work, i.e. #define MISA_EXT_INFO(_bit, _propname, _descr) \ [__builtin_ctz(_bit)] = {.name = _propname, .description = _descr} and then MISA_EXT_INFO(RVA, "a", "Atomic instructions"), MISA_EXT_INFO(RVD, "d", "Double-precision float point"), ... (We don't need the ctz32() wrapper since we know we'll never input zero to __builtin_ctz().) > + > +static const MISAExtInfo misa_ext_info_arr[] = { > + MISA_EXT_INFO('A', "a", "Atomic instructions"), > + MISA_EXT_INFO('C', "c", "Compressed instructions"), > + MISA_EXT_INFO('D', "d", "Double-precision float point"), > + MISA_EXT_INFO('F', "f", "Single-precision float point"), > + MISA_EXT_INFO('I', "i", "Base integer instruction set"), > + MISA_EXT_INFO('E', "e", "Base integer instruction set (embedded)"), > + MISA_EXT_INFO('M', "m", "Integer multiplication and division"), > + MISA_EXT_INFO('S', "s", "Supervisor-level instructions"), > + MISA_EXT_INFO('U', "u", "User-level instructions"), > + MISA_EXT_INFO('H', "h", "Hypervisor"), > + MISA_EXT_INFO('J', "x-j", "Dynamic translated languages"), > + MISA_EXT_INFO('V', "v", "Vector operations"), > + MISA_EXT_INFO('G', "g", "General purpose (IMAFD_Zicsr_Zifencei)"), > +}; > + > +const char *riscv_get_misa_ext_name(uint32_t bit) > +{ > + return misa_ext_info_arr[ctz32(bit)].name; > +} > + > +const char *riscv_get_misa_ext_descr(uint32_t bit) nit: I'd prefer riscv_get_misa_ext_description() for the name. > +{ > + return misa_ext_info_arr[ctz32(bit)].description; > +} > + > +#define MISA_CFG(_bit, _enabled) \ > + {.misa_bit = _bit, .enabled = _enabled} > + > +static RISCVCPUMisaExtConfig misa_ext_cfgs[] = { > + MISA_CFG(RVA, true), > + MISA_CFG(RVC, true), > + MISA_CFG(RVD, true), > + MISA_CFG(RVF, true), > + MISA_CFG(RVI, true), > + MISA_CFG(RVE, false), > + MISA_CFG(RVM, true), > + MISA_CFG(RVS, true), > + MISA_CFG(RVU, true), > + MISA_CFG(RVH, true), > + MISA_CFG(RVJ, false), > + MISA_CFG(RVV, false), > + MISA_CFG(RVG, false), > }; > > static void riscv_cpu_add_misa_properties(Object *cpu_obj) > @@ -1592,7 +1616,10 @@ static void riscv_cpu_add_misa_properties(Object > *cpu_obj) > int i; > > for (i = 0; i < ARRAY_SIZE(misa_ext_cfgs); i++) { > - const RISCVCPUMisaExtConfig *misa_cfg = &misa_ext_cfgs[i]; > + RISCVCPUMisaExtConfig *misa_cfg = &misa_ext_cfgs[i]; > + > + misa_cfg->name = riscv_get_misa_ext_name(misa_cfg->misa_bit); > + misa_cfg->description = riscv_get_misa_ext_descr(misa_cfg->misa_bit); This might be necessary for the KVM side, but we should be able to avoid this runtime setting here where the compiler can be certain everything is a constant. We just need the old MISA_CFG() back, slightly tweaked to use __builtin_ctz(). > > object_property_add(cpu_obj, misa_cfg->name, "bool", > cpu_get_misa_ext_cfg, > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h > index cc20ee25a7..acae118b9b 100644 > --- a/target/riscv/cpu.h > +++ b/target/riscv/cpu.h > @@ -41,7 +41,10 @@ > > #define RV(x) ((target_ulong)1 << (x - 'A')) > > -/* Consider updating misa_ext_cfgs[] when adding new MISA bits here */ > +/* > + * Consider updating misa_ext_info_arr[] and misa_ext_cfgs[] > + * when adding new MISA bits here. > + */ > #define RVI RV('I') > #define RVE RV('E') /* E and I are mutually exclusive */ > #define RVM RV('M') > @@ -56,6 +59,8 @@ > #define RVJ RV('J') > #define RVG RV('G') > > +const char *riscv_get_misa_ext_name(uint32_t bit); > +const char *riscv_get_misa_ext_descr(uint32_t bit); > > /* Privileged specification version */ > enum { > -- > 2.41.0 > Thanks, drew