[U-Boot-Users] [PATCH] fix system config overwrite @ MPC834x

[Andre Schwarz]

Kim,

during 83xx setup the "System I/O configuration register high" gets 
overwritten
with user defined value if CFG_SICRH is defined.

Regarding to the MPC834x manual (Table 5-28 reve.1) bits 28+29 of SICRH 
must keep
their reset value regardless of configuration.

On my board (using RGMII) those bits are set after reset - yet it's 
unclear where they come from.

The patch keeps both bits on MPC834x.


Cheers,
Andre

Signed-off-by: Andre Schwarz <andre.schwarz at matrix-vision.de>
--

 cpu/mpc83xx/cpu_init.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/cpu/mpc83xx/cpu_init.c b/cpu/mpc83xx/cpu_init.c
index fba5b02..66cc1c2 100644
--- a/cpu/mpc83xx/cpu_init.c
+++ b/cpu/mpc83xx/cpu_init.c
@@ -59,6 +59,8 @@ static void config_qe_ioports(void)
  */
 void cpu_init_f (volatile immap_t * im)
 {
+    u32 tmp_sicrh = 0;
+
     /* Pointer is writable since we allocated a register for it */
     gd = (gd_t *) (CFG_INIT_RAM_ADDR + CFG_GBL_DATA_OFFSET);
 
@@ -181,7 +183,11 @@ void cpu_init_f (volatile immap_t * im)
 
     /* System General Purpose Register */
 #ifdef CFG_SICRH
-    im->sysconf.sicrh = CFG_SICRH;
+#ifdef CONFIG_MPC834X
+    /* regarding to MPC34x manual rev.1 bits 28..29 must be preserved */
+    tmp_sicrh = im->sysconf.sicrh & 0x0000000C;
+#endif
+    im->sysconf.sicrh = CFG_SICRH | tmp_sicrh;
 #endif
 #ifdef CFG_SICRL
     im->sysconf.sicrl = CFG_SICRL;


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