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From: Marek Vasut <marex@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 07/13] i.MX28: Shut down the LCD controller before reset
Date: Tue,  1 May 2012 23:03:46 +0200	[thread overview]
Message-ID: <1335906232-24549-8-git-send-email-marex@denx.de> (raw)
In-Reply-To: <1335906232-24549-1-git-send-email-marex@denx.de>

If the LCD controller is on before the CPU goes into reset, the traffic on LCDIF
data pins interferes with the BootROM's boot mode sampling. So shut the
controller down.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Detlev Zundel <dzu@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
---
 arch/arm/cpu/arm926ejs/mx28/mx28.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/arm926ejs/mx28/mx28.c b/arch/arm/cpu/arm926ejs/mx28/mx28.c
index 865dbb3..a82ff25 100644
--- a/arch/arm/cpu/arm926ejs/mx28/mx28.c
+++ b/arch/arm/cpu/arm926ejs/mx28/mx28.c
@@ -51,9 +51,16 @@ void reset_cpu(ulong ignored) __attribute__((noreturn));
 
 void reset_cpu(ulong ignored)
 {
-
 	struct mx28_rtc_regs *rtc_regs =
 		(struct mx28_rtc_regs *)MXS_RTC_BASE;
+	struct mx28_lcdif_regs *lcdif_regs =
+		(struct mx28_lcdif_regs *)MXS_LCDIF_BASE;
+
+	/*
+	 * Shut down the LCD controller as it interferes with BootROM boot mode
+	 * pads sampling.
+	 */
+	writel(LCDIF_CTRL_RUN, &lcdif_regs->hw_lcdif_ctrl_clr);
 
 	/* Wait 1 uS before doing the actual watchdog reset */
 	writel(1, &rtc_regs->hw_rtc_watchdog);
-- 
1.7.10

  parent reply	other threads:[~2012-05-01 21:03 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-01 21:03 [U-Boot] [PATCH 00/13] M28EVK/i.MX28 improvements Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 01/13] FEC: Abstract out register setup Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 02/13] M28EVK: Implement support for new board V2.0 Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 03/13] M28EVK: Add SD update command Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 04/13] i.MX28: Improve passing of data from SPL to U-Boot Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 05/13] i.MX28: Implement boot pads sampling and reporting Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 06/13] i.MX28: Add LCDIF register definitions Marek Vasut
2012-05-01 21:03 ` Marek Vasut [this message]
2012-05-01 21:03 ` [U-Boot] [PATCH 08/13] i.MX28: Add LRADC " Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 09/13] i.MX28: Add LRADC init to i.MX28 SPL Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 10/13] i.MX28: Reorder battery status functions in SPL Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 11/13] i.MX28: Add battery boot components to SPL Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 12/13] i.MX28: Check if WP detection is implemented at all Marek Vasut
2012-05-01 21:03 ` [U-Boot] [PATCH 13/13] i.MX28: Avoid redefining serial_put[cs]() Marek Vasut
2012-05-01 21:05 ` [U-Boot] [PATCH 00/13] M28EVK/i.MX28 improvements Marek Vasut
  -- strict thread matches above, loose matches on Subject: below --
2012-05-01 21:09 Marek Vasut
2012-05-01 21:09 ` [U-Boot] [PATCH 07/13] i.MX28: Shut down the LCD controller before reset Marek Vasut

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