CSR_STIMECMP
context->stimecmp = csr_read(CSR_STIMECMP);
csr_write(CSR_STIMECMP, ULONG_MAX);
csr_write(CSR_STIMECMP, context->stimecmp);
csr_write(CSR_STIMECMP, ULONG_MAX);
csr_write(CSR_STIMECMP, ULONG_MAX);
csr_write(CSR_STIMECMP, next_tval & 0xFFFFFFFF);
csr_write(CSR_STIMECMP, next_tval);
csr_write(CSR_STIMECMP, cval);
return csr_read(CSR_STIMECMP);