[U-Boot] [PATCH 2/2] i.MX: shut down video before launch of O/S

[Eric Nelson]

Hi Fabio,

On 09/21/2012 03:41 PM, Fabio Estevam wrote:
> Hi Eric,
>
> Thanks for working on this. I will try it probably tomorrow.
>
> On Fri, Sep 21, 2012 at 5:36 PM, Eric Nelson
> <eric.nelson at boundarydevices.com>  wrote:
>> Signed-off-by: Eric Nelson<eric.nelson at boundarydevices.com>
>
> Please add a commit log description. This is an important bug fix.
>
> With the framebuffer enabled in U-boot, I get kernel hangs at
> aproximately 50% of the times I boot a 2.6.35 kernel on a mx53qsb.
>

Ok.

>> ---
>>   arch/arm/imx-common/Makefile     |    1 +
>>   arch/arm/imx-common/preboot_os.c |   34 ++++++++++++++++++++++++++++++++++
>>   2 files changed, 35 insertions(+), 0 deletions(-)
>>   create mode 100644 arch/arm/imx-common/preboot_os.c
>>
>> diff --git a/arch/arm/imx-common/Makefile b/arch/arm/imx-common/Makefile
>> index b3e608e..31dc52e 100644
>> --- a/arch/arm/imx-common/Makefile
>> +++ b/arch/arm/imx-common/Makefile
>> @@ -32,6 +32,7 @@ COBJS-y       = iomux-v3.o timer.o cpu.o speed.o
>>   COBJS-$(CONFIG_I2C_MXC) += i2c-mxv7.o
>>   endif
>>   COBJS-$(CONFIG_CMD_BMODE) += cmd_bmode.o
>> +COBJS-y += preboot_os.o
>>   COBJS  := $(sort $(COBJS-y))
>>
>>   SRCS   := $(SOBJS:.o=.S) $(COBJS:.o=.c)
>> diff --git a/arch/arm/imx-common/preboot_os.c b/arch/arm/imx-common/preboot_os.c
>> new file mode 100644
>> index 0000000..ed7a9e0
>> --- /dev/null
>> +++ b/arch/arm/imx-common/preboot_os.c
>
> Do we really need a new file to store a single function?
>
> What about placing it at arch/arm/imx-common/cpu.c ?
>
That seems reasonable.

>> @@ -0,0 +1,34 @@
>> +/*
>> + * Copyright (C) 2012 Boundary Devices Inc.
>> + *
>> + * See file CREDITS for list of people who contributed to this
>> + * project.
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License as
>> + * published by the Free Software Foundation; either version 2 of
>> + * the License, or (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
>> + * MA 02111-1307 USA
>> + */
>> +#include<common.h>
>> +
>> +#if defined(CONFIG_VIDEO_IPUV3)
>> +#include<ipu_pixfmt.h>
>> +#endif
>
> ifdef's for headers is not recommended.
>

Ok.

>> +
>> +void arch_preboot_os(void)
>> +{
>> +#if defined(CONFIG_VIDEO_IPUV3)
>> +       /* disable video before launching O/S */
>> +       ipuv3_fb_shutdown();
>> +#endif
>
> The #if defined(CONFIG_VIDEO_IPUV3) could go outside of the arch_preboot_os().
>

That occurred to me as well, but I figured this might not be the only
bit that could/should/might be shut down prior to O/S boot (USB?) and
that this would make that clearer.

Regards,


Eric