Aaron Durbin (adurbin@google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3169
-gerrit
commit 0d9fe82d753b3960b8105c9c7d9590330852f50f Author: Aaron Durbin adurbin@chromium.org Date: Wed May 1 15:39:28 2013 -0500
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 --- src/cpu/intel/haswell/Kconfig | 3 +- src/cpu/intel/haswell/Makefile.inc | 3 ++ src/cpu/intel/haswell/tsc_freq.c | 31 +++++++++++++++ src/northbridge/intel/haswell/Makefile.inc | 1 - src/northbridge/intel/haswell/udelay.c | 63 ------------------------------ 5 files changed, 36 insertions(+), 65 deletions(-)
diff --git a/src/cpu/intel/haswell/Kconfig b/src/cpu/intel/haswell/Kconfig index 13861f9..152059f 100644 --- a/src/cpu/intel/haswell/Kconfig +++ b/src/cpu/intel/haswell/Kconfig @@ -8,7 +8,8 @@ config CPU_SPECIFIC_OPTIONS def_bool y select SMP select SSE2 - select UDELAY_LAPIC + select UDELAY_TSC + select TSC_CONSTANT_RATE select SMM_TSEG select SMM_MODULES select RELOCATABLE_MODULES diff --git a/src/cpu/intel/haswell/Makefile.inc b/src/cpu/intel/haswell/Makefile.inc index 90ffd66..60c061d 100644 --- a/src/cpu/intel/haswell/Makefile.inc +++ b/src/cpu/intel/haswell/Makefile.inc @@ -1,7 +1,9 @@ ramstage-y += haswell_init.c subdirs-y += ../../x86/name ramstage-y += mp_init.c +ramstage-y += tsc_freq.c romstage-y += romstage.c +romstage-y += tsc_freq.c
ramstage-$(CONFIG_GENERATE_ACPI_TABLES) += acpi.c ramstage-$(CONFIG_HAVE_SMI_HANDLER) += smmrelocate.c @@ -10,6 +12,7 @@ ramstage-$(CONFIG_MONOTONIC_TIMER_MSR) += monotonic_timer.c cpu_microcode-$(CONFIG_CPU_MICROCODE_CBFS_GENERATE) += microcode_blob.c
smm-$(CONFIG_HAVE_SMI_HANDLER) += finalize.c +smm-$(CONFIG_HAVE_SMI_HANDLER) += tsc_freq.c
cpu_incs += $(src)/cpu/intel/haswell/cache_as_ram.inc
diff --git a/src/cpu/intel/haswell/tsc_freq.c b/src/cpu/intel/haswell/tsc_freq.c new file mode 100644 index 0000000..0a78053 --- /dev/null +++ b/src/cpu/intel/haswell/tsc_freq.c @@ -0,0 +1,31 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2013 Google, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <stdint.h> +#include <cpu/x86/msr.h> +#include <cpu/x86/tsc.h> +#include "cpu/intel/haswell/haswell.h" + +unsigned long tsc_freq_mhz(void) +{ + msr_t platform_info; + + platform_info = rdmsr(MSR_PLATFORM_INFO); + return HASWELL_BCLK * ((platform_info.lo >> 8) & 0xff); +} diff --git a/src/northbridge/intel/haswell/Makefile.inc b/src/northbridge/intel/haswell/Makefile.inc index 896360d..b2ac85e 100644 --- a/src/northbridge/intel/haswell/Makefile.inc +++ b/src/northbridge/intel/haswell/Makefile.inc @@ -29,7 +29,6 @@ romstage-y += early_init.c romstage-y += report_platform.c romstage-y += ../../../arch/x86/lib/walkcbfs.S
-smm-$(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 f5d541e..0000000 --- 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))); -}
-
Aaron Durbin