The next command reveals the variety of efficiency cores and effectivity cores and the CPU sort:

sysctl -a|egrep 'brand_string|(perflevel.*(physicalcpu:|title))'

On my MacBook Professional M1 this provides the next output:

hw.perflevel0.physicalcpu: 8
hw.perflevel0.title: Efficiency
hw.perflevel1.physicalcpu: 2
hw.perflevel1.title: Effectivity
machdep.cpu.brand_string: Apple M1 Professional

You can even enter this shorter command to get the caches sizes as nicely:

sysctl -a|grep perfl

On my MacBook Professional M1 this produces:

hw.perflevel0.physicalcpu: 8
hw.perflevel0.physicalcpu_max: 8
hw.perflevel0.logicalcpu: 8
hw.perflevel0.logicalcpu_max: 8
hw.perflevel0.l1icachesize: 196608 
hw.perflevel0.l1dcachesize: 131072
hw.perflevel0.l2cachesize: 12582912
hw.perflevel0.cpusperl2: 4
hw.perflevel0.title: Efficiency
hw.perflevel1.physicalcpu: 2
hw.perflevel1.physicalcpu_max: 2
hw.perflevel1.logicalcpu: 2
hw.perflevel1.logicalcpu_max: 2
hw.perflevel1.l1icachesize: 131072
hw.perflevel1.l1dcachesize: 65536
hw.perflevel1.l2cachesize: 4194304
hw.perflevel1.cpusperl2: 2
hw.perflevel1.title: Effectivity
hw.nperflevels: 2