timer: Add generic udelay() implementation

Add GENERIC_UDELAY Kconfig option so that a generic
udelay() implementation is provided utilizing the
monotonic timer. That way each board/chipset doesn't
need to duplicate the same udelay(). Additionally,
assume that GENERIC_UDELAY implies init_timer()
is not required.

BUG=None
BRANCH=None
TEST=Built nyan, ryu, and rambi. May need help testing.

Change-Id: I7f511a2324b5aa5d1b2959f4519be85a6a7360e8
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 1a85fbcad778933d13eaef545135abe7e4de46ed
Original-Change-Id: Idd26de19eefc91ee3b0ceddfb1bc2152e19fd8ab
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/219719
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9334
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
This commit is contained in:
Aaron Durbin
2014-09-25 10:05:15 -05:00
committed by Patrick Georgi
parent 23b4e4c4e8
commit e5e36306a9
19 changed files with 24 additions and 240 deletions

View File

@@ -22,6 +22,8 @@ bootblock-y += prog_ops.c
bootblock-y += cbfs.c cbfs_core.c
bootblock-$(CONFIG_COMMON_CBFS_SPI_WRAPPER) += cbfs_spi.c
bootblock-$(CONFIG_GENERIC_UDELAY) += timer.c
bootblock-$(CONFIG_CONSOLE_CBMEM) += cbmem_console.c
bootblock-y += memchr.c
bootblock-y += memcmp.c
@@ -61,6 +63,8 @@ romstage-$(CONFIG_ARCH_ROMSTAGE_X86_32) += gcc.c
ramstage-$(CONFIG_ARCH_RAMSTAGE_X86_32) += gcc.c
endif
romstage-$(CONFIG_GENERIC_UDELAY) += timer.c
ramstage-y += prog_ops.c
ramstage-y += hardwaremain.c
ramstage-y += selfboot.c
@@ -89,6 +93,7 @@ ramstage-y += memrange.c
ramstage-$(CONFIG_COOP_MULTITASKING) += thread.c
ramstage-$(CONFIG_TIMER_QUEUE) += timer_queue.c
ramstage-$(CONFIG_TERTIARY_BOARD_ID) += tristate_gpios.c
ramstage-$(CONFIG_GENERIC_UDELAY) += timer.c
romstage-y += cbmem_common.c dynamic_cbmem.c
ramstage-y += cbmem_common.c dynamic_cbmem.c

42
src/lib/timer.c Normal file
View File

@@ -0,0 +1,42 @@
/*
* This file is part of the coreboot project.
*
* Copyright 2014 Google Inc.
*
* 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; version 2 of the License.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <console/console.h>
#include <timer.h>
#include <delay.h>
#include <thread.h>
void udelay(unsigned usec)
{
struct stopwatch sw;
/*
* As the timer granularity is in microseconds pad the
* requested delay by one to get at least >= requested usec delay.
*/
usec += 1;
if (!thread_yield_microseconds(usec))
return;
stopwatch_init_usecs_expire(&sw, usec);
while (!stopwatch_expired(&sw))
;
}