From: Wolfgang Denk <wd@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 01/10] arm: Compile cache_disable() with -O2 to avoid failure
Date: Sat, 03 Nov 2012 13:29:11 +0100 [thread overview]
Message-ID: <20121103122911.4587A200255@gemini.denx.de> (raw)
In-Reply-To: <1351813330-23741-1-git-send-email-sjg@chromium.org>
Dear Simon Glass,
In message <1351813330-23741-1-git-send-email-sjg@chromium.org> you wrote:
> It is good to have these functions written in C instead of assembler,
> but with -O0 the cache_disable() function doesn't return. Rather than
> revert to assembler, this fix just forces this to be built with -O2.
NAK.
This is vodoo programming to fix a problem which is obviously not
correctly understood (and fixed), so the real cause remains unfixed.
> +/*
> + * Big hack warning!
> + *
> + * Devs like to compile with -O0 to get a nice debugging illusion. But this
We don't use -O0 normally, and actually there are more places in the
code that are likely to cause problems or to actually break when
using -O0.
> + * function does not survive that since -O0 causes the compiler to read the
> + * PC back from the stack after the dcache flush. Might it be possible to fix
> + * this by flushing the write buffer?
> + */
"compiler to read the PC back from the stack after the dcache flush" -
can you please explain what exactly this means, and which exact
problem it causes?
> +static void cache_disable(uint32_t cache_bit) __attribute__ ((optimize(2)));
Sorry, I will not accept this.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
backups: always in season, never out of style.
next prev parent reply other threads:[~2012-11-03 12:29 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-01 23:42 [U-Boot] [PATCH 01/10] arm: Compile cache_disable() with -O2 to avoid failure Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 02/10] arm: move flush_dcache_all() to just before disable cache Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 03/10] arm: Keep track of the tlb size as well as its location Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 04/10] arm: Move fdt check earlier so that board_early_init_f() can use it Simon Glass
2012-11-03 14:56 ` Wolfgang Denk
2012-11-03 21:53 ` Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 05/10] arm: Add CONFIG_DELAY_ENVIRONMENT to delay environment loading Simon Glass
2012-11-03 12:30 ` Wolfgang Denk
2012-11-07 0:16 ` Simon Glass
2013-01-18 12:06 ` Lucas Stach
2013-01-18 13:29 ` Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 06/10] arm: Add CONFIG_DISPLAY_BOARDINFO_LATE to display board info on LCD Simon Glass
2012-11-03 12:33 ` Wolfgang Denk
2012-11-15 22:37 ` Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 07/10] arm: Add option to display customised memory information Simon Glass
2012-11-03 14:54 ` Wolfgang Denk
2012-11-15 22:45 ` Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 08/10] arm: Make interrupts.o and reset.o in libarm also appear in SPL Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 09/10] arm: Move bootstage record for board_init_f() to after arch_cpu_init() Simon Glass
2012-11-03 14:55 ` Wolfgang Denk
2012-11-07 0:51 ` Simon Glass
2012-11-07 13:18 ` Wolfgang Denk
2012-11-22 14:57 ` Simon Glass
2012-11-01 23:42 ` [U-Boot] [PATCH 10/10] arm: Tabify code for MMC initialization Simon Glass
2012-11-03 8:32 ` [U-Boot] [PATCH 01/10] arm: Compile cache_disable() with -O2 to avoid failure Marek Vasut
2012-11-03 12:29 ` Wolfgang Denk [this message]
2012-11-07 0:45 ` Simon Glass
2012-11-07 12:55 ` Wolfgang Denk
2012-11-07 15:42 ` Simon Glass
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