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haswell: Parallel AP bringup

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This patch parallelizes the AP startup for Haswell-based devices. It
does not touch the generic secondary startup code. Instead it provides
its own MP support matching up with the Haswell BWG. It seemed to be too
much trouble to support the old startup way and this new way. Because of
that parallel loading is the only thing supported.

A couple of things to note:
1. Micrcode needs to be loaded twice. Once before MTRR and caching is
   enabled. And a second time after SMM relocation.
2. The sipi_vector is entirely self-contained. Once it is loaded and
   written back to RAM the APs do not access memory outside of the
   sipi_vector load location until a sync up in ramstage.
3. SMM relocation is kicked off by an IPI to self w/ SMI set as the
   destination mode.

The following are timings from cbmem with dev mode disabled and recovery mode
enabled to boot directly into the kernel. This was done on the
baskingridge CRB with a 4-core 8-thread CPU and 2 DIMMs 1GiB each. The
kernel has console enabled on the serial port. Entry 70 is the device
initialization, and that is where the APs are brought up. With these two
examples it looks to shave off ~200 ms of boot time.

Before:
   1:55,382
   2:57,606 (2,223)
   3:3,108,983 (3,051,377)
   4:3,110,084 (1,101)
   8:3,113,109 (3,024)
   9:3,156,694 (43,585)
  10:3,156,815 (120)
  30:3,157,110 (295)
  40:3,158,180 (1,069)
  50:3,160,157 (1,977)
  60:3,160,366 (208)
  70:4,221,044 (1,060,677)
  75:4,221,062 (18)
  80:4,227,185 (6,122)
  90:4,227,669 (484)
  99:4,265,596 (37,927)
1000:4,267,822 (2,225)
1001:4,268,507 (685)
1002:4,268,780 (272)
1003:4,398,676 (129,896)
1004:4,398,979 (303)
1100:7,477,601 (3,078,621)
1101:7,480,210 (2,608)

After:
   1:49,518
   2:51,778 (2,259)
   3:3,081,186 (3,029,407)
   4:3,082,252 (1,066)
   8:3,085,137 (2,884)
   9:3,130,339 (45,202)
  10:3,130,518 (178)
  30:3,130,544 (26)
  40:3,131,125 (580)
  50:3,133,023 (1,897)
  60:3,133,278 (255)
  70:4,009,259 (875,980)
  75:4,009,273 (13)
  80:4,015,947 (6,674)
  90:4,016,430 (482)
  99:4,056,265 (39,835)
1000:4,058,492 (2,226)
1001:4,059,176 (684)
1002:4,059,450 (273)
1003:4,189,333 (129,883)
1004:4,189,770 (436)
1100:7,262,358 (3,072,588)
1101:7,263,926 (1,567)

Booted the baskingridge board as noted above. Also analyzed serial
messages with pcserial enabled.

Change-Id: Ifedc7f787953647c228b11afdb725686e38c4098
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2779
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This commit is contained in:
Aaron Durbin
2013-01-15 08:27:05 -06:00
committed by Ronald G. Minnich
parent 98ffb426f4
commit 305b1f0d30
8 changed files with 844 additions and 103 deletions
Download Patch File Download Diff File Expand all files Collapse all files

550
src/cpu/intel/haswell/mp_init.c Normal file
View File

@ -0,0 +1,550 @@
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2013 ChromeOS Authors
*
* 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 <console/console.h>
#include <stdint.h>
#include <rmodule.h>
#include <arch/cpu.h>
#include <cpu/cpu.h>
#include <cpu/intel/microcode.h>
#include <cpu/x86/cache.h>
#include <cpu/x86/lapic.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/smm.h>
#include <delay.h>
#include <device/device.h>
#include <device/path.h>
#include <lib.h>
#include <smp/atomic.h>
#include <smp/spinlock.h>
#include "haswell.h"
/* This needs to match the layout in the .module_parametrs section. */
struct sipi_params {
u16 gdtlimit;
u32 gdt;
u16 unused;
u32 idt_ptr;
u32 stack_top;
u32 stack_size;
u32 microcode_ptr;
u32 msr_table_ptr;
u32 msr_count;
u32 c_handler;
u32 c_handler_arg;
u8 apic_to_cpu_num[CONFIG_MAX_CPUS];
} __attribute__((packed));
/* This also needs to match the assembly code for saved MSR encoding. */
struct saved_msr {
u32 index;
u32 lo;
u32 hi;
} __attribute__((packed));
/* The sipi vector rmodule is included in the ramstage using 'objdump -B'. */
extern char _binary_sipi_vector_start[];
/* These symbols are defined in c_start.S. */
extern char gdt[];
extern char gdt_limit[];
extern char idtarg[];
/* This table keeps track of each CPU's APIC id. */
static u8 apic_id_table[CONFIG_MAX_CPUS];
static device_t cpu_devs[CONFIG_MAX_CPUS];
/* Number of APs checked that have checked in. */
static atomic_t num_aps;
/* Barrier to stop APs from performing SMM relcoation. */
static int smm_relocation_barrier_begin __attribute__ ((aligned (64)));
static inline void wait_for_barrier(volatile int *barrier)
{
while (*barrier == 0) {
asm ("pause");
}
}
static inline void release_barrier(volatile int *barrier)
{
*barrier = 1;
}
static void ap_wait_for_smm_relocation_begin(void)
{
wait_for_barrier(&smm_relocation_barrier_begin);
}
/* Returns 1 if timeout waiting for APs. 0 if target aps found. */
static int wait_for_aps(int target, int total_delay, int delay_step)
{
int timeout = 0;
int delayed = 0;
while (atomic_read(&num_aps) != target) {
udelay(delay_step);
delayed += delay_step;
if (delayed >= total_delay) {
timeout = 1;
break;
}
}
return timeout;
}
void release_aps_for_smm_relocation(void)
{
release_barrier(&smm_relocation_barrier_begin);
}
/* The mtrr code sets up ROM caching on the BSP, but not the others. However,
* the boot loader payload disables this. In order for Linux not to complain
* ensure the caching is disabled for tha APs before going to sleep. */
static void cleanup_rom_caching(void)
{
#if CONFIG_CACHE_ROM
msr_t msr;
unsigned int last_var_mtrr;
msr = rdmsr(MTRRcap_MSR);
last_var_mtrr = (msr.lo & 0xff) - 1;
/* Check if the MTRR is valid. */
msr = rdmsr(MTRRphysMask_MSR(last_var_mtrr));
if ((msr.lo & MTRRphysMaskValid) == 0)
return;
msr = rdmsr(MTRRphysBase_MSR(last_var_mtrr));
/* Assum that if the MTRR is of write protected type, the MTRR is used
* to cache the ROM. */
if ((msr.lo & MTRR_NUM_TYPES) == MTRR_TYPE_WRPROT) {
msr.lo = msr.hi = 0;
disable_cache();
wrmsr(MTRRphysMask_MSR(last_var_mtrr), msr);
wrmsr(MTRRphysBase_MSR(last_var_mtrr), msr);
enable_cache();
}
#endif
}
/* By the time APs call ap_init() caching has been setup, and microcode has
* been loaded. */
static void ap_init(unsigned int cpu, void *microcode_ptr)
{
struct cpu_info *info;
/* Signal that the AP has arrived. */
atomic_inc(&num_aps);
/* Ensure the local apic is enabled */
enable_lapic();
info = cpu_info();
info->index = cpu;
info->cpu = cpu_devs[cpu];
apic_id_table[info->index] = lapicid();
info->cpu->path.apic.apic_id = apic_id_table[info->index];
/* Call through the cpu driver's initialization. */
cpu_initialize(info->index);
ap_wait_for_smm_relocation_begin();
smm_initiate_relocation();
/* After SMM relocation a 2nd microcode load is required. */
intel_microcode_load_unlocked(microcode_ptr);
/* Cleanup ROM caching. */
cleanup_rom_caching();
/* FIXME(adurbin): park CPUs properly -- preferably somewhere in a
* reserved part of memory that the OS cannot get to. */
stop_this_cpu();
}
static void setup_default_sipi_vector_params(struct sipi_params *sp)
{
int i;
sp->gdt = (u32)&gdt;
sp->gdtlimit = (u32)&gdt_limit;
sp->idt_ptr = (u32)&idtarg;
sp->stack_size = CONFIG_STACK_SIZE;
sp->stack_top = (u32)&_estack;
/* Adjust the stack top to take into account cpu_info. */
sp->stack_top -= sizeof(struct cpu_info);
/* Default to linear APIC id space. */
for (i = 0; i < CONFIG_MAX_CPUS; i++)
sp->apic_to_cpu_num[i] = i;
}
#define NUM_FIXED_MTRRS 11
static unsigned int fixed_mtrrs[NUM_FIXED_MTRRS] = {
MTRRfix64K_00000_MSR, MTRRfix16K_80000_MSR, MTRRfix16K_A0000_MSR,
MTRRfix4K_C0000_MSR, MTRRfix4K_C8000_MSR, MTRRfix4K_D0000_MSR,
MTRRfix4K_D8000_MSR, MTRRfix4K_E0000_MSR, MTRRfix4K_E8000_MSR,
MTRRfix4K_F0000_MSR, MTRRfix4K_F8000_MSR,
};
static inline struct saved_msr *save_msr(int index, struct saved_msr *entry)
{
msr_t msr;
msr = rdmsr(index);
entry->index = index;
entry->lo = msr.lo;
entry->hi = msr.hi;
/* Return the next entry. */
entry++;
return entry;
}
static int save_bsp_msrs(char *start, int size)
{
int msr_count;
int num_var_mtrrs;
struct saved_msr *msr_entry;
int i;
msr_t msr;
/* Determine number of MTRRs need to be saved. */
msr = rdmsr(MTRRcap_MSR);
num_var_mtrrs = msr.lo & 0xff;
/* 2 * num_var_mtrrs for base and mask. +1 for IA32_MTRR_DEF_TYPE. */
msr_count = 2 * num_var_mtrrs + NUM_FIXED_MTRRS + 1;
if ((msr_count * sizeof(struct saved_msr)) > size) {
printk(BIOS_CRIT, "Cannot mirror all %d msrs.\n", msr_count);
return -1;
}
msr_entry = (void *)start;
for (i = 0; i < NUM_FIXED_MTRRS; i++) {
msr_entry = save_msr(fixed_mtrrs[i], msr_entry);
}
for (i = 0; i < num_var_mtrrs; i++) {
msr_entry = save_msr(MTRRphysBase_MSR(i), msr_entry);
msr_entry = save_msr(MTRRphysMask_MSR(i), msr_entry);
}
msr_entry = save_msr(MTRRdefType_MSR, msr_entry);
return msr_count;
}
/* The SIPI vector is loaded at the SMM_DEFAULT_BASE. The reason is at the
* memory range is already reserved so the OS cannot use it. That region is
* free to use for AP bringup before SMM is initialized. */
static u32 sipi_vector_location = SMM_DEFAULT_BASE;
static int sipi_vector_location_size = SMM_DEFAULT_SIZE;
static int load_sipi_vector(const void *microcode_patch)
{
struct rmodule sipi_mod;
int module_size;
int num_msrs;
struct sipi_params *sp;
char *mod_loc = (void *)sipi_vector_location;
const int loc_size = sipi_vector_location_size;
if (rmodule_parse(&_binary_sipi_vector_start, &sipi_mod)) {
printk(BIOS_CRIT, "Unable to parse sipi module.\n");
return -1;
}
if (rmodule_entry_offset(&sipi_mod) != 0) {
printk(BIOS_CRIT, "SIPI module entry offset is not 0!\n");
return -1;
}
if (rmodule_load_alignment(&sipi_mod) != 4096) {
printk(BIOS_CRIT, "SIPI module load alignment(%d) != 4096.\n",
rmodule_load_alignment(&sipi_mod));
return -1;
}
module_size = rmodule_memory_size(&sipi_mod);
/* Align to 4 bytes. */
module_size += 3;
module_size &= ~3;
if (module_size > loc_size) {
printk(BIOS_CRIT, "SIPI module size (%d) > region size (%d).\n",
module_size, loc_size);
return -1;
}
num_msrs = save_bsp_msrs(&mod_loc[module_size], loc_size - module_size);
if (num_msrs < 0) {
printk(BIOS_CRIT, "Error mirroring BSP's msrs.\n");
return -1;
}
if (rmodule_load(mod_loc, &sipi_mod)) {
printk(BIOS_CRIT, "Unable to load SIPI module.\n");
return -1;
}
sp = rmodule_parameters(&sipi_mod);
if (sp == NULL) {
printk(BIOS_CRIT, "SIPI module has no parameters.\n");
return -1;
}
setup_default_sipi_vector_params(sp);
/* Setup MSR table. */
sp->msr_table_ptr = (u32)&mod_loc[module_size];
sp->msr_count = num_msrs;
/* Provide pointer to microcode patch. */
sp->microcode_ptr = (u32)microcode_patch;
/* The microcode pointer is passed on through to the c handler so
* that it can be loaded again after SMM relocation. */
sp->c_handler_arg = (u32)microcode_patch;
sp->c_handler = (u32)&ap_init;
/* Make sure SIPI vector hits RAM so the APs that come up will see
* the startup code even if the caches are disabled. */
wbinvd();
return 0;
}
static int allocate_cpu_devices(struct bus *cpu_bus, int *total_hw_threads)
{
int i;
int num_threads;
int num_cores;
int max_cpus;
struct cpu_info *info;
msr_t msr;
info = cpu_info();
cpu_devs[info->index] = info->cpu;
apic_id_table[info->index] = info->cpu->path.apic.apic_id;
msr = rdmsr(CORE_THREAD_COUNT_MSR);
num_threads = (msr.lo >> 0) & 0xffff;
num_cores = (msr.lo >> 16) & 0xffff;
printk(BIOS_DEBUG, "CPU has %u cores, %u threads enabled.\n",
num_cores, num_threads);
max_cpus = num_threads;
*total_hw_threads = num_threads;
if (num_threads > CONFIG_MAX_CPUS) {
printk(BIOS_CRIT, "CPU count(%d) exceeds CONFIG_MAX_CPUS(%d)\n",
num_threads, CONFIG_MAX_CPUS);
max_cpus = CONFIG_MAX_CPUS;
}
for (i = 1; i < max_cpus; i++) {
struct device_path cpu_path;
device_t new;
/* Build the cpu device path */
cpu_path.type = DEVICE_PATH_APIC;
cpu_path.apic.apic_id = info->cpu->path.apic.apic_id + i;
/* Allocate the new cpu device structure */
new = alloc_find_dev(cpu_bus, &cpu_path);
if (new == NULL) {
printk(BIOS_CRIT, "Could not allocte cpu device\n");
max_cpus--;
}
cpu_devs[i] = new;
}
return max_cpus;
}
int setup_ap_init(struct bus *cpu_bus, int *max_cpus,
const void *microcode_patch)
{
int num_cpus;
int hw_threads;
/* Default to currently running CPU. */
num_cpus = allocate_cpu_devices(cpu_bus, &hw_threads);
/* Load the SIPI vector. */
if (load_sipi_vector(microcode_patch))
return -1;
*max_cpus = num_cpus;
if (num_cpus < hw_threads) {
printk(BIOS_CRIT,
"ERROR: More HW threads (%d) than support (%d).\n",
hw_threads, num_cpus);
return -1;
}
return 0;
}
/* Returns 1 for timeout. 0 on success. */
static int apic_wait_timeout(int total_delay, int delay_step)
{
int total = 0;
int timeout = 0;
while (lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY) {
udelay(delay_step);
total += delay_step;
if (total >= total_delay) {
timeout = 1;
break;
}
}
return timeout;
}
int start_aps(struct bus *cpu_bus, int ap_count)
{
int sipi_vector;
if (ap_count == 0)
return 0;
/* The vector is sent as a 4k aligned address in one byte. */
sipi_vector = sipi_vector_location >> 12;
if (sipi_vector > 256) {
printk(BIOS_CRIT, "SIPI vector too large! 0x%08x\n",
sipi_vector);
return -1;
}
printk(BIOS_DEBUG, "Attempting to start %d APs\n", ap_count);
if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
printk(BIOS_DEBUG, "Waiting for ICR not to be busy...");
if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
printk(BIOS_DEBUG, "timed out. Aborting.\n");
return -1;
} else
printk(BIOS_DEBUG, "done.\n");
}
/* Send INIT IPI to all but self. */
lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
LAPIC_DM_INIT);
printk(BIOS_DEBUG, "Waiting for INIT to complete...");
/* Wait for 10 ms to complete. */
if (apic_wait_timeout(10000 /* 10 ms */, 100 /* us */)) {
printk(BIOS_DEBUG, "timed out. Bailing. \n");
return -1;
} else {
printk(BIOS_DEBUG, "done.\n");
}
/* Send 1st SIPI */
if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
printk(BIOS_DEBUG, "Waiting for ICR not to be busy...");
if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
printk(BIOS_DEBUG, "timed out. Aborting.\n");
return -1;
} else
printk(BIOS_DEBUG, "done.\n");
}
lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
LAPIC_DM_STARTUP | sipi_vector);
printk(BIOS_DEBUG, "Waiting for 1st SIPI to complete...");
if (apic_wait_timeout(10000 /* 10 ms */, 50 /* us */)) {
printk(BIOS_DEBUG, "timed out.\n");
return -1;
} else {
printk(BIOS_DEBUG, "done.\n");
}
/* Wait for CPUs to check in up to 200 us. */
wait_for_aps(ap_count, 200 /* us */, 15 /* us */);
/* Send 2nd SIPI */
if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
printk(BIOS_DEBUG, "Waiting for ICR not to be busy...");
if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
printk(BIOS_DEBUG, "timed out. Aborting.\n");
return -1;
} else
printk(BIOS_DEBUG, "done.\n");
}
lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
LAPIC_DM_STARTUP | sipi_vector);
printk(BIOS_DEBUG, "Waiting for 2nd SIPI to complete...");
if (apic_wait_timeout(10000 /* 10 ms */, 50 /* us */)) {
printk(BIOS_DEBUG, "timed out.\n");
return -1;
} else {
printk(BIOS_DEBUG, "done.\n");
}
/* Wait for CPUs to check in. */
if (wait_for_aps(ap_count, 10000 /* 10 ms */, 50 /* us */)) {
printk(BIOS_DEBUG, "Not all APs checked in: %d/%d.\n",
atomic_read(&num_aps), ap_count);
return -1;
}
return 0;
}
DECLARE_SPIN_LOCK(smm_relocation_lock);
void smm_initiate_relocation(void)
{
spin_lock(&smm_relocation_lock);
if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
printk(BIOS_DEBUG, "Waiting for ICR not to be busy...");
if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
printk(BIOS_DEBUG, "timed out. Aborting.\n");
spin_unlock(&smm_relocation_lock);
return;
} else
printk(BIOS_DEBUG, "done.\n");
}
lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(lapicid()));
lapic_write_around(LAPIC_ICR, LAPIC_INT_ASSERT | LAPIC_DM_SMI);
if (apic_wait_timeout(1000 /* 1 ms */, 100 /* us */)) {
printk(BIOS_DEBUG, "SMI Relocation timed out.\n");
} else
printk(BIOS_DEBUG, "Relocation complete.\n");
spin_unlock(&smm_relocation_lock);
}