From mboxrd@z Thu Jan 1 00:00:00 1970 From: York Sun Date: Thu, 1 May 2014 15:13:57 -0700 Subject: [U-Boot] [Patch v3 1/2] common/board_f: Preserve early global data In-Reply-To: <1398980503.15726.36.camel@snotra.buserror.net> References: <1398906061-7119-1-git-send-email-yorksun@freescale.com> <5362B9B7.3040703@freescale.com> <1398979305.15726.26.camel@snotra.buserror.net> <5362BCBC.8080802@freescale.com> <1398980503.15726.36.camel@snotra.buserror.net> Message-ID: <5362C725.4020304@freescale.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 05/01/2014 02:41 PM, Scott Wood wrote: > On Thu, 2014-05-01 at 14:29 -0700, York Sun wrote: >> On 05/01/2014 02:21 PM, Scott Wood wrote: >>> On Thu, 2014-05-01 at 14:16 -0700, York Sun wrote: >>>> On 05/01/2014 08:54 AM, Simon Glass wrote: >>>>> Hi York, >>>>> >>>>> On 30 April 2014 18:01, York Sun wrote: >>>>>> Some platforms (including mpc85xx, mpc86xx) use global data before calling >>>>>> function baord_inti_f(). This data should not be cleared later. Any arch >>>>>> which needs to preserve global data should define CONFIG_SYS_EARLY_GD. >>>>>> >>>>>> Signed-off-by: York Sun >>>>>> CC: Scott Wood >>>>>> CC: Simon Glass >>>>>> --- >>>>>> Change log >>>>>> >>>>>> v3: Introduce CONFIG_SYS_EARLY_GD instead of using a list >>>>>> v2: Instead of adding back gd init for all PPC, preserve gd for mpc85xx and mpc86xx. >>>>>> >>>>>> README | 3 +++ >>>>>> arch/powerpc/include/asm/config.h | 2 ++ >>>>>> arch/x86/include/asm/config.h | 1 + >>>>>> common/board_f.c | 10 +++++----- >>>>>> 4 files changed, 11 insertions(+), 5 deletions(-) >>>>>> >>>>>> diff --git a/README b/README >>>>>> index 12758dc..1a51b11 100644 >>>>>> --- a/README >>>>>> +++ b/README >>>>>> @@ -440,6 +440,9 @@ The following options need to be configured: >>>>>> supported, core will start to execute uboot when wakes up. >>>>>> >>>>>> - Generic CPU options: >>>>>> + CONFIG_SYS_EARLY_GD >>>>>> + Defines global data is used before board_init_f(). >>>>>> + >>>>> >>>>> This looks like a good solution, but I believe that 'early' is in fact >>>>> where we are headed. So perhaps you should create an inverted option >>>>> and define it for archs that don't support it? >>>> >>>> I don't disagree for the long term. But since we just start to convert to >>>> generic board, fewer archs need this than those don't. I suggest we try this and >>>> when most archs convert to generic board, we can invert it if needed. >>> >>> Why wait to do it right? Which arches actually don't need this, given >>> that Simon said he thinks ARM needs it as well? >>> >> >> Adding something I can't test? > > By that rationale nobody could ever make changes that aren't localized > to a few boards. That type of development produces the sort of mess > that the generic board is meant to remedy. > >> Even Simon said he thinks ARM needs it, it is not what current code has. If I >> revert this logic, >> >> #ifdef CONFIG_SYS_GLOBAL_DATA_STACK > > This looks like a global stack of data, not global data on the stack. > > How about CONFIG_SYS_GENERIC_GLOBAL_DATA? > >> gd_dt data; >> >> gd = &data; >> zero_global_data(); >> #endif >> >> I need to add #define CONFIG_SYS_GLOBAL_DATA_STACK to the board/arch who needs >> it. I have no idea which needs in the 70+ boards with CONFIG_DISPLAY_BOARDINFO >> defined. > > I see only 10 boards that currently use CONFIG_SYS_GENERIC_BOARD in > include/configs, plus sandbox and x86 which hide it in config.mk. I > don't know what CONFIG_DISPLAY_BOARDINFO has to do with it. To invert > the symbol, add the new symbol to all of the current users. Removal > from ARM boards can come afterward if it's confirmed that it's the right > thing to do. I made a typo when I search it. Yes, it is only 10 boards. I can add the new macro to their arch header file. York York