u-boot/arch/x86/cpu/lapic.c
Bin Meng aaaa55751a x86: Remove SMP limitation in lapic_setup()
At present LAPIC is enabled and configured as virtual wire mode
in lapic_setup() only when CONFIG_SMP is on. This limitation is
however not necessary as for uniprocessor this is still needed.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-05-23 15:27:41 +08:00

159 lines
3.7 KiB
C

/*
* From coreboot file of same name
*
* Copyright (C) 2008-2009 coresystems GmbH
* Copyright (C) 2014 Google, Inc
*
* SPDX-License-Identifier: GPL-2.0
*/
#include <common.h>
#include <asm/io.h>
#include <asm/lapic.h>
#include <asm/msr.h>
#include <asm/msr-index.h>
#include <asm/post.h>
unsigned long lapic_read(unsigned long reg)
{
return readl(LAPIC_DEFAULT_BASE + reg);
}
#define xchg(ptr, v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v), (ptr), \
sizeof(*(ptr))))
struct __xchg_dummy { unsigned long a[100]; };
#define __xg(x) ((struct __xchg_dummy *)(x))
/*
* Note: no "lock" prefix even on SMP. xchg always implies lock anyway.
*
* Note 2: xchg has side effect, so that attribute volatile is necessary,
* but generally the primitive is invalid, *ptr is output argument.
*/
static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
int size)
{
switch (size) {
case 1:
__asm__ __volatile__("xchgb %b0,%1"
: "=q" (x)
: "m" (*__xg(ptr)), "0" (x)
: "memory");
break;
case 2:
__asm__ __volatile__("xchgw %w0,%1"
: "=r" (x)
: "m" (*__xg(ptr)), "0" (x)
: "memory");
break;
case 4:
__asm__ __volatile__("xchgl %0,%1"
: "=r" (x)
: "m" (*__xg(ptr)), "0" (x)
: "memory");
break;
}
return x;
}
void lapic_write(unsigned long reg, unsigned long v)
{
(void)xchg((volatile unsigned long *)(LAPIC_DEFAULT_BASE + reg), v);
}
void enable_lapic(void)
{
if (!IS_ENABLED(CONFIG_INTEL_QUARK)) {
msr_t msr;
msr = msr_read(MSR_IA32_APICBASE);
msr.hi &= 0xffffff00;
msr.lo |= MSR_IA32_APICBASE_ENABLE;
msr.lo &= ~MSR_IA32_APICBASE_BASE;
msr.lo |= LAPIC_DEFAULT_BASE;
msr_write(MSR_IA32_APICBASE, msr);
}
}
void disable_lapic(void)
{
if (!IS_ENABLED(CONFIG_INTEL_QUARK)) {
msr_t msr;
msr = msr_read(MSR_IA32_APICBASE);
msr.lo &= ~MSR_IA32_APICBASE_ENABLE;
msr_write(MSR_IA32_APICBASE, msr);
}
}
unsigned long lapicid(void)
{
return lapic_read(LAPIC_ID) >> 24;
}
static void lapic_wait_icr_idle(void)
{
do { } while (lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY);
}
int lapic_remote_read(int apicid, int reg, unsigned long *pvalue)
{
int timeout;
unsigned long status;
int result;
lapic_wait_icr_idle();
lapic_write(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(apicid));
lapic_write(LAPIC_ICR, LAPIC_DM_REMRD | (reg >> 4));
timeout = 0;
do {
status = lapic_read(LAPIC_ICR) & LAPIC_ICR_RR_MASK;
} while (status == LAPIC_ICR_RR_INPROG && timeout++ < 1000);
result = -1;
if (status == LAPIC_ICR_RR_VALID) {
*pvalue = lapic_read(LAPIC_RRR);
result = 0;
}
return result;
}
void lapic_setup(void)
{
/* Only Pentium Pro and later have those MSR stuff */
debug("Setting up local apic: ");
/* Enable the local apic */
enable_lapic();
/* Set Task Priority to 'accept all' */
lapic_write(LAPIC_TASKPRI,
lapic_read(LAPIC_TASKPRI) & ~LAPIC_TPRI_MASK);
/* Put the local apic in virtual wire mode */
lapic_write(LAPIC_SPIV, (lapic_read(LAPIC_SPIV) &
~(LAPIC_VECTOR_MASK)) | LAPIC_SPIV_ENABLE);
lapic_write(LAPIC_LVT0, (lapic_read(LAPIC_LVT0) &
~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
LAPIC_SEND_PENDING | LAPIC_LVT_RESERVED_1 |
LAPIC_DELIVERY_MODE_MASK)) |
(LAPIC_LVT_REMOTE_IRR | LAPIC_SEND_PENDING |
LAPIC_DELIVERY_MODE_EXTINT));
lapic_write(LAPIC_LVT1, (lapic_read(LAPIC_LVT1) &
~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
LAPIC_SEND_PENDING | LAPIC_LVT_RESERVED_1 |
LAPIC_DELIVERY_MODE_MASK)) |
(LAPIC_LVT_REMOTE_IRR | LAPIC_SEND_PENDING |
LAPIC_DELIVERY_MODE_NMI));
debug("apic_id: 0x%02lx, ", lapicid());
debug("done.\n");
post_code(POST_LAPIC);
}