According to IMX28CEC rev. 4, 10/2018, Table 15. Recommended Operating Conditions, page 16, the VDDD should be set to 1.55V when the CPU is operating at 454MHz. This is the case in U-Boot, hence increase the VDDD voltage. This fixes instability when performing TFTP transfers. Increase the brownout threshold to 1.4V. The documentation recommends 1.45V setting for the brownout, however, this triggers failure during power block init, so keep the brownout slightly lower.

Signed-off-by: Marek Vasut marex@denx.de Cc: Stefano Babic sbabic@denx.de --- arch/arm/cpu/arm926ejs/mxs/spl_power_init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c b/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c index a5c528a18d..7a1b39844e 100644 --- a/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c +++ b/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c @@ -1254,8 +1254,8 @@ void mxs_power_init(void) debug("SPL: Setting VDDIO to 3V3 (brownout @ 3v15)\n"); mxs_power_set_vddx(&mxs_vddio_cfg, 3300, 3150);

- debug("SPL: Setting VDDD to 1V5 (brownout @ 1v315)\n"); - mxs_power_set_vddx(&mxs_vddd_cfg, 1500, 1315); + debug("SPL: Setting VDDD to 1V55 (brownout @ 1v400)\n"); + mxs_power_set_vddx(&mxs_vddd_cfg, 1550, 1400); #ifdef CONFIG_MX23 debug("SPL: Setting mx23 VDDMEM to 2V5 (brownout @ 1v7)\n"); mxs_power_set_vddx(&mxs_vddmem_cfg, 2500, 1700);