Aaron Durbin (adurbin@google.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/3207
-gerrit
commit d96ec2b94d4c07452cf6a9ab8e77af6f48a42476 Author: Aaron Durbin adurbin@chromium.org Date: Mon May 6 12:22:23 2013 -0500
x86: add thread support
Thread support is added for the x86 architecture. Both the local apic and the tsc udelay() functions have a call to thread_yield_microseconds() so as to provide an opportunity to run pending threads.
Change-Id: Ie39b9eb565eb189676c06645bdf2a8720fe0636a Signed-off-by: Aaron Durbin adurbin@chromium.org --- src/Kconfig | 2 +- src/arch/x86/lib/Makefile.inc | 2 ++ src/arch/x86/lib/c_start.S | 9 ++++++ src/arch/x86/lib/thread.c | 58 ++++++++++++++++++++++++++++++++++++++ src/arch/x86/lib/thread_switch.S | 58 ++++++++++++++++++++++++++++++++++++++ src/cpu/intel/haswell/mp_init.c | 2 ++ src/cpu/x86/lapic/apic_timer.c | 4 +++ src/cpu/x86/lapic/lapic_cpu_init.c | 2 ++ src/cpu/x86/tsc/delay_tsc.c | 4 +++ 9 files changed, 140 insertions(+), 1 deletion(-)
diff --git a/src/Kconfig b/src/Kconfig index 5dcd7ba..9fde0e4 100644 --- a/src/Kconfig +++ b/src/Kconfig @@ -326,7 +326,7 @@ config TIMER_QUEUE
config COOP_MULTITASKING def_bool n - depends on TIMER_QUEUE + depends on TIMER_QUEUE && ARCH_X86 help Cooperative multitasking allows callbacks to be multiplexed on the main thread of ramstage. With this enabled it allows for multiple diff --git a/src/arch/x86/lib/Makefile.inc b/src/arch/x86/lib/Makefile.inc index 82f4e62..7cdd3c6 100644 --- a/src/arch/x86/lib/Makefile.inc +++ b/src/arch/x86/lib/Makefile.inc @@ -9,6 +9,8 @@ ramstage-y += memset.c ramstage-y += memcpy.c ramstage-y += ebda.c ramstage-y += rom_media.c +ramstage-$(CONFIG_COOP_MULTITASKING) += thread.c +ramstage-$(CONFIG_COOP_MULTITASKING) += thread_switch.S
romstage-$(CONFIG_EARLY_CONSOLE) += romstage_console.c romstage-y += cbfs_and_run.c diff --git a/src/arch/x86/lib/c_start.S b/src/arch/x86/lib/c_start.S index 32af0cc..e9d072f 100644 --- a/src/arch/x86/lib/c_start.S +++ b/src/arch/x86/lib/c_start.S @@ -10,6 +10,11 @@ _stack: .space CONFIG_MAX_CPUS*CONFIG_STACK_SIZE _estack: +#if CONFIG_COOP_MULTITASKING +.global thread_stacks +thread_stacks: +.space CONFIG_STACK_SIZE*CONFIG_NUM_THREADS +#endif
.section ".textfirst", "ax", @progbits .code32 @@ -45,6 +50,10 @@ _start: /* set new stack */ movl $_estack, %esp
+#if CONFIG_COOP_MULTITASKING + /* Push the thread pointer. */ + pushl $0 +#endif /* Push the cpu index and struct cpu */ pushl $0 pushl $0 diff --git a/src/arch/x86/lib/thread.c b/src/arch/x86/lib/thread.c new file mode 100644 index 0000000..06f8a15 --- /dev/null +++ b/src/arch/x86/lib/thread.c @@ -0,0 +1,58 @@ +/* + * 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 <thread.h> + +/* The stack frame looks like the following after a pushad instruction. */ +struct pushad_regs { + uint32_t edi; /* Offset 0x00 */ + uint32_t esi; /* Offset 0x04 */ + uint32_t ebp; /* Offset 0x08 */ + uint32_t esp; /* Offset 0x0c */ + uint32_t ebx; /* Offset 0x10 */ + uint32_t edx; /* Offset 0x14 */ + uint32_t ecx; /* Offset 0x18 */ + uint32_t eax; /* Offset 0x1c */ +}; + +static inline uintptr_t push_stack(uintptr_t cur_stack, uintptr_t value) +{ + uintptr_t *addr; + + cur_stack -= sizeof(value); + addr = (uintptr_t *)cur_stack; + *addr = value; + return cur_stack; +} + +void arch_prepare_thread(struct thread *t, + void asmlinkage (*thread_entry)(void *), void *arg) +{ + uintptr_t stack = t->stack_current; + + /* Imitate thread_entry(t) with return address of 0. thread_entry() + * is assumed to never return. */ + stack = push_stack(stack, (uintptr_t)arg); + stack = push_stack(stack, (uintptr_t)0); + stack = push_stack(stack, (uintptr_t)thread_entry); + /* Make room for the registers. Ignore intial values. */ + stack -= sizeof(struct pushad_regs); + + t->stack_current = stack; +} diff --git a/src/arch/x86/lib/thread_switch.S b/src/arch/x86/lib/thread_switch.S new file mode 100644 index 0000000..8de1948 --- /dev/null +++ b/src/arch/x86/lib/thread_switch.S @@ -0,0 +1,58 @@ +/* + * 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 + */ +.code32 +.text + +/* + * stack layout after pushad: + * +------------+ + * | save stack | <-- esp + 0x28 + * +------------+ + * | new stack | <-- esp + 0x24 + * +------------+ + * | ret addr | <-- esp + 0x20 + * +------------+ + * | eax | <-- esp + 0x1c + * +------------+ + * | ecx | <-- esp + 0x18 + * +------------+ + * | edx | <-- esp + 0x14 + * +------------+ + * | ebx | <-- esp + 0x10 + * +------------+ + * | orig esp | <-- esp + 0x0c + * +------------+ + * | ebp | <-- esp + 0x08 + * +------------+ + * | esi | <-- esp + 0x04 + * +------------+ + * | edi | <-- esp + 0x00 + * +------------+ + */ +.globl switch_to_thread +switch_to_thread: + pusha + /* Save the current stack */ + movl 0x28(%esp), %ebx + movl %esp, (%ebx) + /* Switch to the new stack. */ + movl 0x24(%esp), %eax + movl %eax, %esp + popa + ret diff --git a/src/cpu/intel/haswell/mp_init.c b/src/cpu/intel/haswell/mp_init.c index deba629..357fbb2 100644 --- a/src/cpu/intel/haswell/mp_init.c +++ b/src/cpu/intel/haswell/mp_init.c @@ -36,6 +36,7 @@ #include <lib.h> #include <smp/atomic.h> #include <smp/spinlock.h> +#include <thread.h> #include "haswell.h"
/* This needs to match the layout in the .module_parametrs section. */ @@ -163,6 +164,7 @@ static void asmlinkage ap_init(unsigned int cpu, void *microcode_ptr) info = cpu_info(); info->index = cpu; info->cpu = cpu_devs[cpu]; + thread_init_cpu_info_non_bsp(info);
apic_id_table[info->index] = lapicid(); info->cpu->path.apic.apic_id = apic_id_table[info->index]; diff --git a/src/cpu/x86/lapic/apic_timer.c b/src/cpu/x86/lapic/apic_timer.c index 749fef0..e5ce62f 100644 --- a/src/cpu/x86/lapic/apic_timer.c +++ b/src/cpu/x86/lapic/apic_timer.c @@ -21,6 +21,7 @@ #include <stdint.h> #include <console/console.h> #include <delay.h> +#include <thread.h> #include <arch/io.h> #include <arch/cpu.h> #include <cpu/x86/car.h> @@ -95,6 +96,9 @@ void udelay(u32 usecs) { u32 start, value, ticks;
+ if (!thread_yield_microseconds(usecs)) + return; + if (!timer_fsb || (lapic_read(LAPIC_LVTT) & (LAPIC_LVT_TIMER_PERIODIC | LAPIC_LVT_MASKED)) != (LAPIC_LVT_TIMER_PERIODIC | LAPIC_LVT_MASKED)) diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c index 69430d5..fbc8aa4 100644 --- a/src/cpu/x86/lapic/lapic_cpu_init.c +++ b/src/cpu/x86/lapic/lapic_cpu_init.c @@ -32,6 +32,7 @@ #include <smp/spinlock.h> #include <cpu/cpu.h> #include <cpu/intel/speedstep.h> +#include <thread.h>
#if CONFIG_SMP && CONFIG_MAX_CPUS > 1 /* This is a lot more paranoid now, since Linux can NOT handle @@ -292,6 +293,7 @@ int start_cpu(device_t cpu) info = (struct cpu_info *)stack_end; info->index = index; info->cpu = cpu; + thread_init_cpu_info_non_bsp(info);
/* Advertise the new stack and index to start_cpu */ secondary_stack = stack_end; diff --git a/src/cpu/x86/tsc/delay_tsc.c b/src/cpu/x86/tsc/delay_tsc.c index 0e2a9c0..b8f2503 100644 --- a/src/cpu/x86/tsc/delay_tsc.c +++ b/src/cpu/x86/tsc/delay_tsc.c @@ -4,6 +4,7 @@ #include <cpu/x86/tsc.h> #include <smp/spinlock.h> #include <delay.h> +#include <thread.h>
#if !defined(__PRE_RAM__)
@@ -176,6 +177,9 @@ void udelay(unsigned us) unsigned long long current; unsigned long long clocks;
+ if (!thread_yield_microseconds(us)) + return; + start = rdtscll(); clocks = us; clocks *= get_clocks_per_usec();