zen/zenxfi: adjust maximum emi voltage

Running at 130MHz is unsafe since on those targets, we disable memory frequency
scaling because it is unstable. That leads to situation where cpu is running at
64MHz and VDD is at 1.050V. But on STMP3700, the EMI uses the VDD rail instead
of a dedicated VDDMEM rail as on STMP3780. Thus we are essentially running the
EMI at 130MHz at 1.050V when the minimum recommened voltage is 1.2V. This commit
runs the EMI at 64MHz all the time on the ZEN and ZEN X-Fi which will lead to
reduce performance but hopefully increases stability.

Change-Id: Ida6c2ec130b1778973e383d7c44a06a6ca8f9268

1 files changed, 2 insertions, 2 deletions

diff --git a/firmware/target/arm/imx233/system-imx233.c b/firmware/target/arm/imx233/system-imx233.c
index 860039b85f..165a32d143 100644
--- a/firmware/target/arm/imx233/system-imx233.c
+++ b/firmware/target/arm/imx233/system-imx233.c
@@ -286,8 +286,8 @@ struct cpufreq_profile_t
 /* Some devices don't handle very well memory frequency changes, so avoid them
  * by running at highest speed at all time */
 #if defined(CREATIVE_ZEN) || defined(CREATIVE_ZENXFI)
-#define EMIFREQ_NORMAL  IMX233_EMIFREQ_130_MHz
-#define EMIFREQ_MAX     IMX233_EMIFREQ_130_MHz
+#define EMIFREQ_NORMAL  IMX233_EMIFREQ_64_MHz
+#define EMIFREQ_MAX     IMX233_EMIFREQ_64_MHz
 #else /* weird targets */
 #define EMIFREQ_NORMAL  IMX233_EMIFREQ_64_MHz
 #define EMIFREQ_MAX     IMX233_EMIFREQ_130_MHz