[U-Boot] [PATCH 3/4 V2] i.MX28: Add delay after CPU bypass is cleared

Marek Vasut marex at denx.de
Thu May 3 17:47:20 CEST 2012


This solves issues when larger amount of DRAM is used. Behave the
same in case of CPU bypass as we do in case of EMI bypass, wait
15 ms. We need to wait until the clock domain stabilizes.

Signed-off-by: Marek Vasut <marex at denx.de>
Cc: Wolfgang Denk <wd at denx.de>
Cc: Detlev Zundel <dzu at denx.de>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Fabio Estevam <festevam at gmail.com>
---

V2: Change the description, this issue seemed to have been caused by not
    waiting after frobbing with the CPU bypass, it was unrelated to memory,
    but had a direct impact, causing trouble. This was yet another X-File
    of the imx-bootlets, sigh.

 arch/arm/cpu/arm926ejs/mx28/spl_mem_init.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/cpu/arm926ejs/mx28/spl_mem_init.c b/arch/arm/cpu/arm926ejs/mx28/spl_mem_init.c
index 0d13537..a9b1bb6 100644
--- a/arch/arm/cpu/arm926ejs/mx28/spl_mem_init.c
+++ b/arch/arm/cpu/arm926ejs/mx28/spl_mem_init.c
@@ -149,6 +149,8 @@ void mx28_mem_setup_cpu_and_hbus(void)
 	/* Disable CPU bypass */
 	writel(CLKCTRL_CLKSEQ_BYPASS_CPU,
 		&clkctrl_regs->hw_clkctrl_clkseq_clr);
+
+	early_delay(15000);
 }
 
 void mx28_mem_setup_vdda(void)
-- 
1.7.10



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