From 7cb1ba9a61b244800eb65c08729f75d85a504de3 Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Wed, 1 May 2013 15:39:28 -0500 Subject: 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 Reviewed-on: http://review.coreboot.org/3169 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Ronald G. Minnich --- src/northbridge/intel/haswell/Makefile.inc | 1 - src/northbridge/intel/haswell/udelay.c | 63 ------------------------------ 2 files changed, 64 deletions(-) delete mode 100644 src/northbridge/intel/haswell/udelay.c (limited to 'src/northbridge/intel') 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 -#include -#include -#include -#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))); -} -- cgit v1.2.3