All of lore.kernel.org
 help / color / mirror / Atom feed
From: Fabio Estevam <festevam@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] mxs: Explain why some mx23 DDR registers are not configured
Date: Sun,  5 May 2013 23:11:59 -0300	[thread overview]
Message-ID: <1367806319-22295-1-git-send-email-festevam@gmail.com> (raw)

From: Fabio Estevam <fabio.estevam@freescale.com>

Put an explanation in the source code as to why some DDR registers do not
need to be configured.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
 arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
index 41fb803..060fdb7 100644
--- a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
+++ b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
@@ -127,6 +127,15 @@ static void initialize_dram_values(void)
 
 	mxs_adjust_memory_params(dram_vals);
 
+	/*
+	 * HW_DRAM_CTL27, HW_DRAM_CTL28 and HW_DRAM_CTL35 are not initialized as
+	 * per FSL bootlets code.
+	 *
+	 * mx23 Reference Manual marks HW_DRAM_CTL27 and HW_DRAM_CTL28 as
+	 * "reserved".
+	 * HW_DRAM_CTL8 is setup as the last element.
+	 * So skip the initialization of these HW_DRAM_CTL registers.
+	 */
 	for (i = 0; i < ARRAY_SIZE(dram_vals); i++) {
 		if (i == 8 || i == 27 || i == 28 || i == 35)
 			continue;
-- 
1.7.9.5

             reply	other threads:[~2013-05-06  2:11 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-06  2:11 Fabio Estevam [this message]
2013-05-06  7:57 ` [U-Boot] [PATCH] mxs: Explain why some mx23 DDR registers are not configured Stefano Babic

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=1367806319-22295-1-git-send-email-festevam@gmail.com \
    --to=festevam@gmail.com \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.