]> git.dujemihanovic.xyz Git - u-boot.git/commit
MPC83XX: Fix GPIO configuration - set gpio level before direction
authorNick Spence <nick.spence@freescale.com>
Sat, 23 Aug 2008 06:52:50 +0000 (23:52 -0700)
committerKim Phillips <kim.phillips@freescale.com>
Wed, 3 Sep 2008 21:06:46 +0000 (16:06 -0500)
commitd9fe88173cb4f7d293796ffe10c7a0d3d426d8f9
tree1e41ed69bee55104040500de9cbfd8f86bc896c6
parent628ffd73bcff0c9f3bc5a8eeb2c7455fe9d28a51
MPC83XX: Fix GPIO configuration - set gpio level before direction

Set DAT value before DIR values to avoid creating glitches on the
GPIO signals.

Set gpio level register before direction register to inhibit
glitches on high level output pins.

Dir and data gets cleared at powerup, so high level output lines see
a short low pulse between setting the direction and level registers.

Issue was seen on a new board with the nReset line of the NOR flash
connected to a GPIO. Setting the direction register puts the NOR flash
in reset so the next instruction to set the level cannot get executed.

Signed-off-by: Nick Spence <nick.spence@freescale.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
cpu/mpc83xx/cpu_init.c