diff options
author | David Hendricks <dhendrix@chromium.org> | 2013-04-12 15:11:05 -0700 |
---|---|---|
committer | Ronald G. Minnich <rminnich@gmail.com> | 2013-04-17 23:06:40 +0200 |
commit | 1fb11d105b4cc0d424884a08814f65e73d36504a (patch) | |
tree | 003151ff5de224099d7d746d8da12b9db8605876 /src/arch/armv7/lib | |
parent | 1a0b5e1c0594cb1bfe5094ad0c6eb183c9f3a593 (diff) |
armv7/exynos5250: Deprecate sdelay in favor of udelay
This gets rid of the clock-tick based sdelay in favor of udelay().
udelay() is more consistent and easier to work with, and this allows
us to carry one less variation of timers (and headers and sources...).
Every 1 unit in the sdelay() argument was assumed to cause a delay of
2 clock ticks (@1.7GHz). So the conversion factor is roughly:
sdelay(N) = udelay(((N * 2) / 1.7 * 10^9) * 10^6)
= udelay((N * 2) / (1.7 * 10^3))
The sdelay() periods used were:
sdelay(100) --> udelay(1)
sdelay(0x10000) --> udelay(78) (rounded up to udelay(100))
There was one instance of sdelay(10000), which looked like sort of a
typo since sdelay(0x10000) was used elsewhere. sdelay(10000) should
approximate to about 12us, so we'll stick with that for now and leave
a note.
Change-Id: I5e7407865ceafa701eea1d613bbe50cf4734f33e
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/3079
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/arch/armv7/lib')
-rw-r--r-- | src/arch/armv7/lib/Makefile.inc | 1 | ||||
-rw-r--r-- | src/arch/armv7/lib/syslib.c | 39 |
2 files changed, 0 insertions, 40 deletions
diff --git a/src/arch/armv7/lib/Makefile.inc b/src/arch/armv7/lib/Makefile.inc index 0cb5737f25..b10c1abc76 100644 --- a/src/arch/armv7/lib/Makefile.inc +++ b/src/arch/armv7/lib/Makefile.inc @@ -5,7 +5,6 @@ bootblock-y += cache.c romstage-y += cache.c romstage-y += div0.c -romstage-y += syslib.c romstage-$(CONFIG_EARLY_CONSOLE) += early_console.c ramstage-y += div0.c diff --git a/src/arch/armv7/lib/syslib.c b/src/arch/armv7/lib/syslib.c deleted file mode 100644 index a6ed080157..0000000000 --- a/src/arch/armv7/lib/syslib.c +++ /dev/null @@ -1,39 +0,0 @@ -/* - * (C) Copyright 2008 - * Texas Instruments, <www.ti.com> - * - * Richard Woodruff <r-woodruff2@ti.com> - * Syed Mohammed Khasim <khasim@ti.com> - * - * 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 <arch/io.h> -#include <system.h> /* FIXME: dumping ground for prototypes */ - -/************************************************************ - * sdelay() - simple spin loop. Will be constant time as - * its generally used in bypass conditions only. This - * is necessary until timers are accessible. - * - * not inline to increase chances its in cache when called - *************************************************************/ -void sdelay(unsigned long loops) -{ - __asm__ volatile ("1:\n" "subs %0, %1, #1\n" - "bne 1b":"=r" (loops):"0"(loops)); -} - |