sbi_cppc_write is never passed the full 64-bit value when __riscv_xlen == 32

[repnop]

opensbi/lib/sbi/sbi_ecall_cppc.c

Line 36 in 791704c

ret = sbi_cppc_write(regs->a0, regs->a1);

Unless there's something I've missed in the SBI specification about CPPC register values never exceeding 32-bits when XLEN is 32, this line is wrong whenever the code is compiled for __riscv_xlen == 32, as it implicitly promotes the unsigned long (32-bits) to a uint64_t instead of reading the full 64-bit value out of a1 and a2 and combining them into a 64-bit value.

[avpatel]

Yes, this line needs to be fixed for RV32. Please send a patch to the OpenSBI mailing list.