From: Marc Leeman <mleeman@users.sourceforge.net>
To: u-boot@lists.denx.de
Subject: [U-Boot-Users] [patch] master read fix mpc8245
Date: Tue, 11 May 2004 10:29:25 +0200 [thread overview]
Message-ID: <20040511082925.GD14935@smtp.barco.com> (raw)
Reading PPC Memory from another device with the PPC as PCI target device
corrupts data due to interenal hardware buffering. Fix to disable these
buffers with no performance influence.
a detailed description is available upon request (pdf, mailinglist
bounces).
-------------- next part --------------
--- u-boot-1.1.1.orig/cpu/mpc824x/cpu_init.c 2003-06-27 23:32:33.000000000 +0200
+++ u-boot-1.1.1/cpu/mpc824x/cpu_init.c 2004-05-10 14:08:17.000000000 +0200
@@ -102,7 +102,25 @@ cpu_init_f (void)
CONFIG_WRITE_BYTE(AMBOR, val & 0xDF);
CONFIG_WRITE_BYTE(AMBOR, val | 0x20);
CONFIG_WRITE_BYTE(AMBOR, val & 0xDF);
+#ifdef CONFIG_MPC8245
+ /* silicon bug 28 MPC8245 */
+ CONFIG_READ_BYTE(AMBOR,val);
+ CONFIG_WRITE_BYTE(AMBOR,val|0x1);
+
+ CONFIG_READ_BYTE(PCMBCR,val);
+ /* in order not to corrupt data which is being read over the PCI bus
+ * with the PPC as master, we need to reduce the number of PCMRBs to 1,
+ * 4.11 in the processor user manual
+ * */
+#if 1
+ CONFIG_WRITE_BYTE(PCMBCR,(val|0xC0)); /* 1 PCMRB */
+#else
+ CONFIG_WRITE_BYTE(PCMBCR,(val|0x80)); /* 2 PCMRBs */
+ CONFIG_WRITE_BYTE(PCMBCR,(val|0x40)); /* 3 PCMRBs */
+#endif
+#endif
+
CONFIG_READ_WORD(PICR1, val);
#if defined(CONFIG_MPC8240)
CONFIG_WRITE_WORD( PICR1,
-------------- next part --------------
--- u-boot-1.1.1.orig/include/mpc824x.h 2002-11-03 01:33:12.000000000 +0100
+++ u-boot-1.1.1/include/mpc824x.h 2004-05-10 14:03:56.000000000 +0200
@@ -297,6 +297,7 @@
#define PBESR 0x800000c7 /* PCI Bus Error Status Register */
#define PBEAR 0x800000c8 /* Processor/PCI Bus Error Status Register */
#define AMBOR 0x800000e0 /* Address Map B Options Register */
+#define PCMBCR 0x800000e1 /* PCI/Memory Buffer Copnfiguration */
#define MCCR1 0x800000f0 /* Memory Control Configuration Register 1 */
#define MCCR2 0x800000f4 /* Memory Control Configuration Register 2 */
#define MCCR3 0x800000f8 /* Memory Control Configuration Register 3 */
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
Url : http://lists.denx.de/pipermail/u-boot/attachments/20040511/b9982a7e/attachment.pgp
next reply other threads:[~2004-05-11 8:29 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-05-11 8:29 Marc Leeman [this message]
2004-05-11 8:56 ` [U-Boot-Users] [patch] master read fix mpc8245 Wolfgang Denk
2004-07-13 6:09 ` Gleb Natapov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20040511082925.GD14935@smtp.barco.com \
--to=mleeman@users.sourceforge.net \
--cc=u-boot@lists.denx.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox