diff options
Diffstat (limited to 'src/cpu/x86')
| -rw-r--r-- | src/cpu/x86/lapic/Config.lb | 8 | ||||
| -rw-r--r-- | src/cpu/x86/lapic/apic_timer.c | 67 | ||||
| -rw-r--r-- | src/cpu/x86/lapic/lapic_cpu_init.c | 2 | ||||
| -rw-r--r-- | src/cpu/x86/tsc/delay_tsc.c | 4 |
4 files changed, 78 insertions, 3 deletions
diff --git a/src/cpu/x86/lapic/Config.lb b/src/cpu/x86/lapic/Config.lb index 8b5eaa376e..b0636f3abd 100644 --- a/src/cpu/x86/lapic/Config.lb +++ b/src/cpu/x86/lapic/Config.lb @@ -1,3 +1,11 @@ +uses CONFIG_UDELAY_LAPIC + object lapic.o object lapic_cpu_init.o object secondary.S + +if CONFIG_UDELAY_LAPIC + default HAVE_INIT_TIMER=1 + object apic_timer.o +end + diff --git a/src/cpu/x86/lapic/apic_timer.c b/src/cpu/x86/lapic/apic_timer.c new file mode 100644 index 0000000000..a4737b3e7c --- /dev/null +++ b/src/cpu/x86/lapic/apic_timer.c @@ -0,0 +1,67 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2007 Advanced Micro Devices, Inc. + * Copyright (C) 2009 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 <stdint.h> +#include <delay.h> +#include <cpu/x86/msr.h> +#include <cpu/x86/lapic.h> + +/* NOTE: This code uses global variables, so it can not be used during + * memory init. + */ + +#define FSB_CLOCK_STS 0xcd + +static u32 timer_fsb = 200; // default to 200MHz + +void init_timer(void) +{ + msr_t fsb_clock_sts; + + /* Set the apic timer to no interrupts and periodic mode */ + lapic_write(LAPIC_LVTT, (1 << 17) | (1<< 16) | (0 << 12) | (0 << 0)); + + /* Set the divider to 1, no divider */ + lapic_write(LAPIC_TDCR, LAPIC_TDR_DIV_1); + + /* Set the initial counter to 0xffffffff */ + lapic_write(LAPIC_TMICT, 0xffffffff); + + /* Set FSB frequency to a reasonable value */ + fsb_clock_sts = rdmsr(FSB_CLOCK_STS); + switch ((fsb_clock_sts.lo >> 4) & 0x07) { + case 0: timer_fsb = 266; break; + case 1: timer_fsb = 133; break; + case 2: timer_fsb = 200; break; + case 3: timer_fsb = 166; break; + case 5: timer_fsb = 100; break; + } +} + +void udelay(u32 usecs) +{ + u32 start, value, ticks; + /* Calculate the number of ticks to run, our FSB runs at timer_fsb Mhz */ + ticks = usecs * timer_fsb; + start = lapic_read(LAPIC_TMCCT); + do { + value = lapic_read(LAPIC_TMCCT); + } while((start - value) < ticks); +} diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c index 4f910d0caf..6d912e62d4 100644 --- a/src/cpu/x86/lapic/lapic_cpu_init.c +++ b/src/cpu/x86/lapic/lapic_cpu_init.c @@ -55,7 +55,7 @@ static void copy_secondary_start_to_1m_below(void) /* need to save it for RAM resume */ lowmem_backup_size = code_size; lowmem_backup = malloc(code_size); - lowmem_backup_ptr = (unsigned char *)start_eip; + lowmem_backup_ptr = (char *)start_eip; if (lowmem_backup == NULL) die("Out of backup memory\n"); diff --git a/src/cpu/x86/tsc/delay_tsc.c b/src/cpu/x86/tsc/delay_tsc.c index 946d2cf512..72b1f7196c 100644 --- a/src/cpu/x86/tsc/delay_tsc.c +++ b/src/cpu/x86/tsc/delay_tsc.c @@ -106,10 +106,10 @@ static unsigned long long calibrate_tsc(void) printk_spew("Calibrating delay loop...\n"); start = rdtscll(); - // no udivdi3, dammit. + // no udivdi3 because we don't like libgcc. (only in x86emu) // so we count to 1<< 20 and then right shift 20 for(count = 0; count < (1<<20); count ++) - outb(0x80, 0x80); + inb(0x80); end = rdtscll(); #if 0 |