[PATCH] powerpc: fixup QE_General4 errata
From: Joakim Tjernlund <hidden>
Date: 2011-08-23 12:38:18
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
QE_General4 should only round up the divisor iff divisor is > 3. Rounding up lower divisors makes the error too big, causing USB on MPC832x to fail. Signed-off-by: Joakim Tjernlund <redacted> --- arch/powerpc/sysdev/qe_lib/qe.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/sysdev/qe_lib/qe.c b/arch/powerpc/sysdev/qe_lib/qe.c
index 093e0ae..5399316 100644
--- a/arch/powerpc/sysdev/qe_lib/qe.c
+++ b/arch/powerpc/sysdev/qe_lib/qe.c@@ -216,7 +216,7 @@ int qe_setbrg(enum qe_clock brg, unsigned int rate, unsigned int multiplier) /* Errata QE_General4, which affects some MPC832x and MPC836x SOCs, says that the BRG divisor must be even if you're not using divide-by-16 mode. */ - if (!div16 && (divisor & 1)) + if (!div16 && (divisor & 1) && (divisor > 3)) divisor++; tempval = ((divisor - 1) << QE_BRGC_DIVISOR_SHIFT) |
--
1.7.3.4