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authorAaron Durbin <adurbin@chromium.org>2013-05-01 15:39:28 -0500
committerRonald G. Minnich <rminnich@gmail.com>2013-05-07 18:32:41 +0200
commit7cb1ba9a61b244800eb65c08729f75d85a504de3 (patch)
treed18c0a0964ebc7b92ddc443774055da043dd7a52 /src/northbridge
parent935850e08293cec1cb27d12358b27285e780566a (diff)
haswell: use tsc for udelay()
Instead of using the local apic timer for udelay() use the tsc. That way SMM, romstage, and ramstage all use the same delay functionality. Change-Id: I024de5af01eb5de09318e13d0428ee98c132f594 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/3169 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/northbridge')
-rw-r--r--src/northbridge/intel/haswell/Makefile.inc1
-rw-r--r--src/northbridge/intel/haswell/udelay.c63
2 files changed, 0 insertions, 64 deletions
diff --git a/src/northbridge/intel/haswell/Makefile.inc b/src/northbridge/intel/haswell/Makefile.inc
index 896360d9ec..b2ac85ec6d 100644
--- a/src/northbridge/intel/haswell/Makefile.inc
+++ b/src/northbridge/intel/haswell/Makefile.inc
@@ -29,7 +29,6 @@ romstage-y += early_init.c
romstage-y += report_platform.c
romstage-y += ../../../arch/x86/lib/walkcbfs.S
-smm-$(CONFIG_HAVE_SMI_HANDLER) += udelay.c
smm-$(CONFIG_HAVE_SMI_HANDLER) += finalize.c
# We don't ship that, but booting without it is bound to fail
diff --git a/src/northbridge/intel/haswell/udelay.c b/src/northbridge/intel/haswell/udelay.c
deleted file mode 100644
index f5d541e8e1..0000000000
--- a/src/northbridge/intel/haswell/udelay.c
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2007-2008 coresystems GmbH
- *
- * 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 <delay.h>
-#include <stdint.h>
-#include <cpu/x86/tsc.h>
-#include <cpu/x86/msr.h>
-#include "cpu/intel/haswell/haswell.h"
-
-/* Simple 32- to 64-bit multiplication. Uses 16-bit words to avoid overflow. */
-static inline void multiply_to_tsc(tsc_t *const tsc, const u32 a, const u32 b)
-{
- tsc->lo = (a & 0xffff) * (b & 0xffff);
- tsc->hi = ((tsc->lo >> 16)
- + ((a & 0xffff) * (b >> 16))
- + ((b & 0xffff) * (a >> 16)));
- tsc->lo = ((tsc->hi & 0xffff) << 16) | (tsc->lo & 0xffff);
- tsc->hi = ((a >> 16) * (b >> 16)) + (tsc->hi >> 16);
-}
-
-void udelay(u32 us)
-{
- u32 dword;
- tsc_t tsc, tsc1, tscd;
- msr_t msr;
- u32 divisor;
- u32 d; /* ticks per us */
-
- msr = rdmsr(MSR_PLATFORM_INFO);
- divisor = (msr.lo >> 8) & 0xff;
-
- d = HASWELL_BCLK * divisor;
- multiply_to_tsc(&tscd, us, d);
-
- tsc1 = rdtsc();
- dword = tsc1.lo + tscd.lo;
- if ((dword < tsc1.lo) || (dword < tscd.lo)) {
- tsc1.hi++;
- }
- tsc1.lo = dword;
- tsc1.hi += tscd.hi;
-
- do {
- tsc = rdtsc();
- } while ((tsc.hi < tsc1.hi)
- || ((tsc.hi == tsc1.hi) && (tsc.lo <= tsc1.lo)));
-}