Re: [PATCH V2] MPC52XX: Don't touch pipelining for MPC5200B

From: Wolfram Sang <redacted>
To: Arnd Bergmann <arnd@arndb.de>
Cc: <redacted>
Sent: Monday, August 18, 2008 9:18:31 AM
Subject: [PATCH V2] MPC52XX: Don't touch pipelining for MPC5200B


MPC5200 needs to have pipelining disabled for ATA to work. MPC5200B does not.
So, for the latter, don't touch the original setting from the bootloader.

Signed-off-by: Wolfram Sang 
---
Hello Arnd,

On Mon, Aug 18, 2008 at 12:49:36PM +0200, Arnd Bergmann wrote:

quoted

Please make this a run-time conditional instead of compile-time.

Like this?

..................................................................

This needs some testing IMHO. Most configs in U-Boot tend to enable pipelining,
which then used to be disabled by the kernel. So, on the one hand, this change
would enable what is originally wanted; on the other hand, systems may run
under a new configuration and need to be checked for regressions. Especially as
there can be puzzling effects, like for one setup here, FEC only works reliably
with pipelining enabled.

arch/powerpc/platforms/52xx/mpc52xx_common.c |    7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

Index: arch/powerpc/platforms/52xx/mpc52xx_common.c
===================================================================

--- arch/powerpc/platforms/52xx/mpc52xx_common.c.orig
+++ arch/powerpc/platforms/52xx/mpc52xx_common.c

@@ -99,11 +99,14 @@
    out_be32(&xlb->master_pri_enable, 0xff);
    out_be32(&xlb->master_priority, 0x11111111);

-    /* Disable XLB pipelining