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crypto: caam - increase TRNG clocks per sample

we need to configure the TRNG to use more clocks per sample
to handle the two back-to-back 64KiB random descriptor requests
on higher frequency P5040s.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Kim Phillips 12 years ago
parent
commit
a5bbf6fa79
1 changed files with 3 additions and 3 deletions
  1. 3 3
      drivers/crypto/caam/ctrl.c

+ 3 - 3
drivers/crypto/caam/ctrl.c

@@ -129,7 +129,7 @@ static int instantiate_rng(struct device *jrdev)
 
 /*
  * By default, the TRNG runs for 200 clocks per sample;
- * 800 clocks per sample generates better entropy.
+ * 1600 clocks per sample generates better entropy.
  */
 static void kick_trng(struct platform_device *pdev)
 {
@@ -144,9 +144,9 @@ static void kick_trng(struct platform_device *pdev)
 
 	/* put RNG4 into program mode */
 	setbits32(&r4tst->rtmctl, RTMCTL_PRGM);
-	/* 800 clocks per sample */
+	/* 1600 clocks per sample */
 	val = rd_reg32(&r4tst->rtsdctl);
-	val = (val & ~RTSDCTL_ENT_DLY_MASK) | (800 << RTSDCTL_ENT_DLY_SHIFT);
+	val = (val & ~RTSDCTL_ENT_DLY_MASK) | (1600 << RTSDCTL_ENT_DLY_SHIFT);
 	wr_reg32(&r4tst->rtsdctl, val);
 	/* min. freq. count */
 	wr_reg32(&r4tst->rtfrqmin, 400);