+ if ((cha_vid & CHA_ID_RNG_MASK) >> CHA_ID_RNG_SHIFT >= 4) {
+ ctrlpriv->rng4_sh_init =
+ rd_reg32(&topregs->ctrl.r4tst[0].rdsta);
+ /*
+ * If the secure keys (TDKEK, JDKEK, TDSK), were already
+ * generated, signal this to the function that is instantiating
+ * the state handles. An error would occur if RNG4 attempts
+ * to regenerate these keys before the next POR.
+ */
+ gen_sk = ctrlpriv->rng4_sh_init & RDSTA_SKVN ? 0 : 1;
+ ctrlpriv->rng4_sh_init &= RDSTA_IFMASK;
+ do {
+ int inst_handles =
+ rd_reg32(&topregs->ctrl.r4tst[0].rdsta) &
+ RDSTA_IFMASK;
+ /*
+ * If either SH were instantiated by somebody else
+ * (e.g. u-boot) then it is assumed that the entropy
+ * parameters are properly set and thus the function
+ * setting these (kick_trng(...)) is skipped.
+ * Also, if a handle was instantiated, do not change
+ * the TRNG parameters.
+ */
+ if (!(ctrlpriv->rng4_sh_init || inst_handles)) {
+ kick_trng(pdev, ent_delay);
+ ent_delay += 400;
+ }
+ /*
+ * if instantiate_rng(...) fails, the loop will rerun
+ * and the kick_trng(...) function will modfiy the
+ * upper and lower limits of the entropy sampling
+ * interval, leading to a sucessful initialization of
+ * the RNG.
+ */
+ ret = instantiate_rng(dev, inst_handles,
+ gen_sk);
+ } while ((ret == -EAGAIN) && (ent_delay < RTSDCTL_ENT_DLY_MAX));