// Code for manipulating stack locations.
//
-// Copyright (C) 2009-2014 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2009-2015 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "output.h" // dprintf
#include "romfile.h" // romfile_loadint
#include "stacks.h" // struct mutex_s
+#include "string.h" // memset
#include "util.h" // useRTC
#define MAIN_STACK_MAX (1024*1024)
u8 cmosindex;
u8 a20;
u16 ss, fs, gs;
+ u32 cr0;
struct descloc_s gdt;
-} Call32Data VARLOW;
+} Call16Data VARLOW;
-#define C32_SLOPPY 1
-#define C32_SMM 2
+#define C16_BIG 1
+#define C16_SMM 2
int HaveSmmCall32 VARFSEG;
-// Backup state in preparation for call32_smm()
-static void
-call32_smm_prep(void)
-{
+// Backup state in preparation for call32
+static int
+call32_prep(u8 method)
+{
+ if (!CONFIG_CALL32_SMM || method != C16_SMM) {
+ // Backup cr0
+ u32 cr0 = cr0_read();
+ if (cr0 & CR0_PE)
+ // Called in 16bit protected mode?!
+ return -1;
+ SET_LOW(Call16Data.cr0, cr0);
+
+ // Backup fs/gs and gdt
+ SET_LOW(Call16Data.fs, GET_SEG(FS));
+ SET_LOW(Call16Data.gs, GET_SEG(GS));
+ struct descloc_s gdt;
+ sgdt(&gdt);
+ SET_LOW(Call16Data.gdt.length, gdt.length);
+ SET_LOW(Call16Data.gdt.addr, gdt.addr);
+
+ // Enable a20 and backup its previous state
+ SET_LOW(Call16Data.a20, set_a20(1));
+ }
+
+ // Backup ss
+ SET_LOW(Call16Data.ss, GET_SEG(SS));
+
// Backup cmos index register and disable nmi
u8 cmosindex = inb(PORT_CMOS_INDEX);
outb(cmosindex | NMI_DISABLE_BIT, PORT_CMOS_INDEX);
inb(PORT_CMOS_DATA);
- SET_LOW(Call32Data.cmosindex, cmosindex);
-
- // Backup ss
- SET_LOW(Call32Data.ss, GET_SEG(SS));
+ SET_LOW(Call16Data.cmosindex, cmosindex);
- SET_LOW(Call32Data.method, C32_SMM);
+ SET_LOW(Call16Data.method, method);
+ return 0;
}
-// Restore state backed up during call32_smm()
-static void
-call32_smm_post(void)
+// Restore state backed up during call32
+static u8
+call32_post(void)
{
- SET_LOW(Call32Data.method, 0);
- SET_LOW(Call32Data.ss, 0);
+ u8 method = GET_LOW(Call16Data.method);
+ SET_LOW(Call16Data.method, 0);
+ SET_LOW(Call16Data.ss, 0);
+
+ if (!CONFIG_CALL32_SMM || method != C16_SMM) {
+ // Restore a20
+ set_a20(GET_LOW(Call16Data.a20));
+
+ // Restore gdt and fs/gs
+ struct descloc_s gdt;
+ gdt.length = GET_LOW(Call16Data.gdt.length);
+ gdt.addr = GET_LOW(Call16Data.gdt.addr);
+ lgdt(&gdt);
+ SET_SEG(FS, GET_LOW(Call16Data.fs));
+ SET_SEG(GS, GET_LOW(Call16Data.gs));
+
+ // Restore cr0
+ u32 cr0_caching = GET_LOW(Call16Data.cr0) & (CR0_CD|CR0_NW);
+ if (cr0_caching)
+ cr0_mask(CR0_CD|CR0_NW, cr0_caching);
+ }
// Restore cmos index register
- outb(GET_LOW(Call32Data.cmosindex), PORT_CMOS_INDEX);
+ outb(GET_LOW(Call16Data.cmosindex), PORT_CMOS_INDEX);
inb(PORT_CMOS_DATA);
+ return method;
+}
+
+// Force next call16() to restore to a pristine cpu environment state
+static void
+call16_override(int big)
+{
+ ASSERT32FLAT();
+ if (getesp() > BUILD_STACK_ADDR)
+ panic("call16_override with invalid stack\n");
+ memset(&Call16Data, 0, sizeof(Call16Data));
+ if (big) {
+ Call16Data.method = C16_BIG;
+ Call16Data.a20 = 1;
+ } else {
+ Call16Data.a20 = !CONFIG_DISABLE_A20;
+ }
+}
+
+// 16bit handler code called from call16() / call16_smm()
+u32 VISIBLE16
+call16_helper(u32 eax, u32 edx, u32 (*func)(u32 eax, u32 edx))
+{
+ u8 method = call32_post();
+ u32 ret = func(eax, edx);
+ call32_prep(method);
+ return ret;
}
#define ASM32_SWITCH16 " .pushsection .text.32fseg." UNIQSEC "\n .code16\n"
{
ASSERT16();
dprintf(9, "call32_smm %p %x\n", func, eax);
- call32_smm_prep();
+ call32_prep(C16_SMM);
u32 bkup_esp;
asm volatile(
// Backup esp / set esp to flat stack location
: "=&r" (bkup_esp), "+r" (eax)
: "r" (func)
: "eax", "ecx", "edx", "ebx", "cc", "memory");
- call32_smm_post();
+ call32_post();
dprintf(9, "call32_smm done %p %x\n", func, eax);
return eax;
}
-// 16bit handler code called from call16_smm()
-u32 VISIBLE16
-call16_smm_helper(u32 eax, u32 edx, u32 (*func)(u32 eax, u32 edx))
-{
- if (!CONFIG_CALL32_SMM)
- return eax;
- call32_smm_post();
- u32 ret = func(eax, edx);
- call32_smm_prep();
- return ret;
-}
-
static u32
call16_smm(u32 eax, u32 edx, void *func)
{
return eax;
func -= BUILD_BIOS_ADDR;
dprintf(9, "call16_smm %p %x %x\n", func, eax, edx);
- u32 stackoffset = Call32Data.ss << 4;
+ u32 stackoffset = Call16Data.ss << 4;
asm volatile(
// Restore esp
" subl %0, %%esp\n"
ASM32_SWITCH16
"1:movl %1, %%eax\n"
" movl %3, %%ecx\n"
- " calll _cfunc16_call16_smm_helper\n"
+ " calll _cfunc16_call16_helper\n"
" movl %%eax, %1\n"
" movl $" __stringify(CALL32SMM_CMDID) ", %%eax\n"
return eax;
}
-// Backup state in preparation for call32_sloppy()
-static void
-call32_sloppy_prep(void)
-{
- // Backup cmos index register and disable nmi
- u8 cmosindex = inb(PORT_CMOS_INDEX);
- outb(cmosindex | NMI_DISABLE_BIT, PORT_CMOS_INDEX);
- inb(PORT_CMOS_DATA);
- SET_LOW(Call32Data.cmosindex, cmosindex);
-
- // Enable a20 and backup it's previous state
- SET_LOW(Call32Data.a20, set_a20(1));
-
- // Backup ss/fs/gs and gdt
- SET_LOW(Call32Data.ss, GET_SEG(SS));
- SET_LOW(Call32Data.fs, GET_SEG(FS));
- SET_LOW(Call32Data.gs, GET_SEG(GS));
- struct descloc_s gdt;
- sgdt(&gdt);
- SET_LOW(Call32Data.gdt.length, gdt.length);
- SET_LOW(Call32Data.gdt.addr, gdt.addr);
-
- SET_LOW(Call32Data.method, C32_SLOPPY);
-}
-
-// Restore state backed up during call32_sloppy()
-static void
-call32_sloppy_post(void)
-{
- SET_LOW(Call32Data.method, 0);
- SET_LOW(Call32Data.ss, 0);
-
- // Restore gdt and fs/gs
- struct descloc_s gdt;
- gdt.length = GET_LOW(Call32Data.gdt.length);
- gdt.addr = GET_LOW(Call32Data.gdt.addr);
- lgdt(&gdt);
- SET_SEG(FS, GET_LOW(Call32Data.fs));
- SET_SEG(GS, GET_LOW(Call32Data.gs));
-
- // Restore a20
- set_a20(GET_LOW(Call32Data.a20));
-
- // Restore cmos index register
- outb(GET_LOW(Call32Data.cmosindex), PORT_CMOS_INDEX);
- inb(PORT_CMOS_DATA);
-}
-
-// Call a C function in 32bit mode. This clobbers the 16bit segment
-// selector registers.
-static u32
-call32_sloppy(void *func, u32 eax)
+// Call a 32bit SeaBIOS function from a 16bit SeaBIOS function.
+u32 VISIBLE16
+__call32(void *func, u32 eax, u32 errret)
{
ASSERT16();
- call32_sloppy_prep();
+ if (CONFIG_CALL32_SMM && GET_GLOBAL(HaveSmmCall32))
+ return call32_smm(func, eax);
+ // Jump direclty to 32bit mode - this clobbers the 16bit segment
+ // selector registers.
+ int ret = call32_prep(C16_BIG);
+ if (ret)
+ return errret;
u32 bkup_ss, bkup_esp;
asm volatile(
// Backup ss/esp / set esp to flat stack location
// Transition to 32bit mode, call func, return to 16bit
" movl $(" __stringify(BUILD_BIOS_ADDR) " + 1f), %%edx\n"
- " jmp transition32\n"
+ " jmp transition32_nmi_off\n"
ASM16_SWITCH32
"1:calll *%3\n"
" movl $2f, %%edx\n"
: "=&r" (bkup_ss), "=&r" (bkup_esp), "+a" (eax)
: "r" (func)
: "ecx", "edx", "cc", "memory");
- call32_sloppy_post();
+ call32_post();
return eax;
}
-// 16bit handler code called from call16_sloppy()
-u32 VISIBLE16
-call16_sloppy_helper(u32 eax, u32 edx, u32 (*func)(u32 eax, u32 edx))
-{
- call32_sloppy_post();
- u32 ret = func(eax, edx);
- call32_sloppy_prep();
- return ret;
-}
-
-// Jump back to 16bit mode while in 32bit mode from call32_sloppy()
+// Call a 16bit SeaBIOS function, restoring the mode from last call32().
static u32
-call16_sloppy(u32 eax, u32 edx, void *func)
+call16(u32 eax, u32 edx, void *func)
{
ASSERT32FLAT();
if (getesp() > MAIN_STACK_MAX)
- panic("call16_sloppy with invalid stack\n");
+ panic("call16 with invalid stack\n");
+ if (CONFIG_CALL32_SMM && Call16Data.method == C16_SMM)
+ return call16_smm(eax, edx, func);
+
+ extern void transition16big(void);
+ extern void transition16(void);
+ void *thunk = transition16;
+ if (Call16Data.method == C16_BIG || in_post())
+ thunk = transition16big;
func -= BUILD_BIOS_ADDR;
- u32 stackseg = Call32Data.ss;
+ u32 stackseg = Call16Data.ss;
asm volatile(
// Transition to 16bit mode
" movl $(1f - " __stringify(BUILD_BIOS_ADDR) "), %%edx\n"
- " jmp transition16big\n"
+ " jmp *%%ecx\n"
// Setup ss/esp and call func
ASM32_SWITCH16
- "1:movl %3, %%ecx\n"
- " shll $4, %3\n"
+ "1:movl %2, %%ecx\n"
+ " shll $4, %2\n"
" movw %%cx, %%ss\n"
- " subl %3, %%esp\n"
+ " subl %2, %%esp\n"
" movw %%cx, %%ds\n"
- " movl %2, %%edx\n"
- " movl %1, %%ecx\n"
- " calll _cfunc16_call16_sloppy_helper\n"
+ " movl %4, %%edx\n"
+ " movl %3, %%ecx\n"
+ " calll _cfunc16_call16_helper\n"
// Return to 32bit and restore esp
" movl $2f, %%edx\n"
- " jmp transition32\n"
- ASM32_BACK32
- "2:addl %3, %%esp\n"
- : "+a" (eax)
- : "r" (func), "r" (edx), "r" (stackseg)
- : "edx", "ecx", "cc", "memory");
- return eax;
-}
-
-// Call a 32bit SeaBIOS function from a 16bit SeaBIOS function.
-u32 VISIBLE16
-call32(void *func, u32 eax, u32 errret)
-{
- ASSERT16();
- if (CONFIG_CALL32_SMM && GET_GLOBAL(HaveSmmCall32))
- return call32_smm(func, eax);
- u32 cr0 = getcr0();
- if (cr0 & CR0_PE)
- // Called in 16bit protected mode?!
- return errret;
- return call32_sloppy(func, eax);
-}
-
-// Call a 16bit SeaBIOS function from a 32bit SeaBIOS function.
-static u32
-call16(u32 eax, u32 edx, void *func)
-{
- ASSERT32FLAT();
- if (getesp() > BUILD_STACK_ADDR)
- panic("call16 with invalid stack\n");
- func -= BUILD_BIOS_ADDR;
- asm volatile(
- // Transition to 16bit mode
- " movl $(1f - " __stringify(BUILD_BIOS_ADDR) "), %%edx\n"
- " jmp transition16\n"
- // Call func
- ASM32_SWITCH16
- "1:movl %2, %%edx\n"
- " calll *%1\n"
- // Return to 32bit
- " movl $2f, %%edx\n"
- " jmp transition32\n"
- ASM32_BACK32
- "2:\n"
- : "+a" (eax)
- : "r" (func), "r" (edx)
- : "edx", "ecx", "cc", "memory");
- return eax;
-}
-
-// Call a 16bit SeaBIOS function in "big real" mode.
-static u32
-call16big(u32 eax, u32 edx, void *func)
-{
- ASSERT32FLAT();
- if (getesp() > BUILD_STACK_ADDR)
- panic("call16big with invalid stack\n");
- func -= BUILD_BIOS_ADDR;
- asm volatile(
- // Transition to 16bit mode
- " movl $(1f - " __stringify(BUILD_BIOS_ADDR) "), %%edx\n"
- " jmp transition16big\n"
- // Call func
- ASM32_SWITCH16
- "1:movl %2, %%edx\n"
- " calll *%1\n"
- // Return to 32bit
- " movl $2f, %%edx\n"
- " jmp transition32\n"
+ " jmp transition32_nmi_off\n"
ASM32_BACK32
- "2:\n"
- : "+a" (eax)
+ "2:addl %2, %%esp\n"
+ : "+a" (eax), "+c"(thunk), "+r"(stackseg)
: "r" (func), "r" (edx)
- : "edx", "ecx", "cc", "memory");
+ : "edx", "cc", "memory");
return eax;
}
-// Call a 16bit SeaBIOS function, restoring the mode from last call32().
-static u32
-call16_back(u32 eax, u32 edx, void *func)
-{
- ASSERT32FLAT();
- if (CONFIG_CALL32_SMM && Call32Data.method == C32_SMM)
- return call16_smm(eax, edx, func);
- if (Call32Data.method == C32_SLOPPY)
- return call16_sloppy(eax, edx, func);
- if (in_post())
- return call16big(eax, edx, func);
- return call16(eax, edx, func);
-}
-
/****************************************************************
* Extra 16bit stack
// Switch to the extra stack and call a function.
u32
-stack_hop(u32 eax, u32 edx, void *func)
+__stack_hop(u32 eax, u32 edx, void *func)
{
if (on_extra_stack())
return ((u32 (*)(u32, u32))func)(eax, edx);
// Switch back to original caller's stack and call a function.
u32
-stack_hop_back(u32 eax, u32 edx, void *func)
+__stack_hop_back(u32 eax, u32 edx, void *func)
{
if (!MODESEGMENT)
- return call16_back(eax, edx, func);
+ return call16(eax, edx, func);
if (!MODE16 || !on_extra_stack())
return ((u32 (*)(u32, u32))func)(eax, edx);
ASSERT16();
_farcall16(struct bregs *callregs, u16 callregseg)
{
if (need_hop_back()) {
- extern void _cfunc16__farcall16(void);
- stack_hop_back((u32)callregs, callregseg, _cfunc16__farcall16);
+ stack_hop_back(_farcall16, callregs, callregseg);
return;
}
ASSERT16();
: "ebx", "ecx", "esi", "edi", "cc", "memory");
}
+// Invoke external 16bit code.
void
farcall16(struct bregs *callregs)
{
- extern void _cfunc16__farcall16(void);
- call16((u32)callregs, 0, _cfunc16__farcall16);
+ call16_override(0);
+ _farcall16(callregs, 0);
}
+// Invoke external 16bit code in "big real" mode.
void
farcall16big(struct bregs *callregs)
{
- extern void _cfunc16__farcall16(void);
- call16big((u32)callregs, 0, _cfunc16__farcall16);
+ call16_override(1);
+ _farcall16(callregs, 0);
}
// Invoke a 16bit software interrupt.
callregs->code.offset = offset;
if (!MODESEGMENT) {
callregs->code.seg = SEG_BIOS;
- _farcall16((void*)callregs - Call32Data.ss * 16, Call32Data.ss);
+ _farcall16((void*)callregs - Call16Data.ss * 16, Call16Data.ss);
return;
}
callregs->code.seg = GET_SEG(CS);
{
extern void reset_vector(void) __noreturn;
if (!MODE16)
- call16_back(0, 0, reset_vector);
+ call16(0, 0, reset_vector);
reset_vector();
}
return (void*)ALIGN_DOWN(esp, THREADSTACKSIZE);
}
-static int ThreadControl;
+static u8 CanInterrupt, ThreadControl;
// Initialize the support for internal threads.
void
-thread_init(void)
+thread_setup(void)
{
+ CanInterrupt = 1;
if (! CONFIG_THREADS)
return;
ThreadControl = romfile_loadint("etc/threads", 1);
int
threads_during_optionroms(void)
{
- return CONFIG_THREADS && ThreadControl == 2 && in_post();
+ return CONFIG_THREADS && CONFIG_RTC_TIMER && ThreadControl == 2 && in_post();
}
// Switch to next thread stack.
void VISIBLE16
check_irqs(void)
{
+ if (!MODESEGMENT && !CanInterrupt) {
+ // Can't enable interrupts (PIC and/or IVT not yet setup)
+ cpu_relax();
+ return;
+ }
if (need_hop_back()) {
- extern void _cfunc16_check_irqs(void);
- stack_hop_back(0, 0, _cfunc16_check_irqs);
+ stack_hop_back(check_irqs, 0, 0);
return;
}
+ if (MODE16)
+ clock_poll_irq();
asm volatile("sti ; nop ; rep ; nop ; cli ; cld" : : :"memory");
}
wait_irq(void)
{
if (need_hop_back()) {
- extern void _cfunc16_wait_irq(void);
- stack_hop_back(0, 0, _cfunc16_wait_irq);
+ stack_hop_back(wait_irq, 0, 0);
return;
}
asm volatile("sti ; hlt ; cli ; cld": : :"memory");
void
yield_toirq(void)
{
- if (!MODESEGMENT && have_threads()) {
- // Threads still active - do a yield instead.
+ if (!CONFIG_HARDWARE_IRQ
+ || (!MODESEGMENT && (have_threads() || !CanInterrupt))) {
+ // Threads still active or irqs not available - do a yield instead.
yield();
return;
}
void
check_preempt(void)
{
- extern void _cfunc32flat_yield_preempt(void);
if (CONFIG_THREADS && GET_GLOBAL(CanPreempt) && have_threads())
- call32(_cfunc32flat_yield_preempt, 0, 0);
+ call32(yield_preempt, 0, 0);
}
}
u32
-call32_params(void *func, u32 eax, u32 edx, u32 ecx, u32 errret)
+__call32_params(void *func, u32 eax, u32 edx, u32 ecx, u32 errret)
{
ASSERT16();
struct call32_params_s params = {func, eax, edx, ecx};
- extern void _cfunc32flat_call32_params_helper(void);
- return call32(_cfunc32flat_call32_params_helper
- , (u32)MAKE_FLATPTR(GET_SEG(SS), ¶ms), errret);
+ return call32(call32_params_helper, MAKE_FLATPTR(GET_SEG(SS), ¶ms)
+ , errret);
}
Code Review / kvmfornfv.git / blobdiff