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IRQ assignment: add & enable 32bit PCI BIOS call for PCI_SET_INTERRUPT.
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@crazii
crazii committed Jan 19, 2024
1 parent 2a430d4 commit 0d5691f
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Showing 2 changed files with 184 additions and 7 deletions.
164 changes: 159 additions & 5 deletions mpxplay/au_cards/pcibios.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -372,13 +372,17 @@ typedef struct
_Static_assert(sizeof(IRQRoutingTable) == 16, "size error");

#include "../../sbemu/dpmi/dbgutil.h"
//#include "../../sbemu/pic.h"
#include "../../sbemu/pic.h"
#include <dpmi.h>
//copied & modified from usbddos
//https://people.freebsd.org/~jhb/papers/bsdcan/2007/article/node4.html
//https://people.freebsd.org/~jhb/papers/bsdcan/2007/article/node5.html
//PCI BIOS SPECIFICATION Revision 2.1
uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
{
if(!pcibios_GetBus())
return 0xFF;

uint8_t INTPIN = pcibios_ReadConfig_Byte(ppkey, PCIR_INTR_PIN);
_LOG("INTPIN: INT%c#, bdf: %d %d %d\n", 'A'+INTPIN-1, ppkey->bBus, ppkey->bDev, ppkey->bFunc);
if(INTPIN > 4 || INTPIN < 1) //[1,4]
Expand Down Expand Up @@ -522,7 +526,7 @@ uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
pcibios_WriteConfig_Byte(ppkey, PCIR_INTR_LN, irq); //found a shared IRQ, it's gonna work.
else if(map != 0) //no conflict
{
_LOG("PCI dedicated IRQ map: %x", (uint16_t)r.EBX);
_LOG("PCI dedicated IRQ map: %x\n", (uint16_t)r.EBX);
if(map&(uint16_t)r.EBX)
map &= (uint16_t)r.EBX; //prefer PCI dedicated IRQ

Expand All @@ -541,9 +545,10 @@ uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
assert(irq > 2 && irq <= 15);

//ENTER_CRITICAL;
//mask out the IRQ incase it's not handled by BIOS by deafult, and system will be overwhelmed by the IRQ
//mask out the IRQ incase it's not handled by BIOS by deafult (not the default IRQ used by BIOS setup), and system will be overwhelmed by the IRQ
//code outside is responsible to unmask it.
//PIC_MaskIRQ(irq);
uint16_t irqmask = PIC_GetIRQMask();
PIC_MaskIRQ(irq);

pcibios_clear_regs(r);
r.EAX = (PCI_FUNCTION_ID<<8)|PCI_SET_INTERRUPT;
Expand All @@ -553,7 +558,156 @@ uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
r.SS = rmstack.segment;
r.SP = STACK_SIZE;
_LOG("PCI_SET_INTERRUPT INT%c#->%d\n", 'A'+INTPIN-1, irq);

#define USE_P32_CALL 1 //32bit protected mode call. if this doesn't work for some PCs, then the final solution should be programming the interrupt router.
typedef struct
{
char signature[4];
uint32_t entry; //physical addr
uint8_t reivision;
uint8_t len; //in paragraph
uint8_t checksum;
uint8_t zero[5];
}BIOS32SD;
_Static_assert(sizeof(BIOS32SD) == 16, "size error");

char* scanarea = (char*)malloc(0xFFFFF-0xE0000);
dosget(scanarea, 0xE0000, 0xFFFFF-0xE0000);
const BIOS32SD* sd = NULL;
int count = (0xFFFFF-0xE0000)/sizeof(BIOS32SD);
for(int i = 0; i < count; ++i)
{
const BIOS32SD* test = (const BIOS32SD*)(scanarea + i * sizeof(BIOS32SD));
if(memcmp(test->signature,"_32_", 4) == 0 && memcmp(test->zero,"\0\0\0\0\0", 5) == 0 && test->len == 1)
{
const char* bytes = (const char*)test;
uint8_t checksum = 0;
for(int i = 0; i < 16; i++)
checksum += bytes[i];
if(checksum == 0)
{
sd = test;
break;
}
}
}
if(sd == NULL) //not found
{
free(scanarea);
pds_dpmi_dos_freemem(&rmstack);
pds_dpmi_dos_freemem(&dosmem);
free(table);
return 0xFF;
}
_LOG("Found BIOS32 Service Directory at %x, entry point %x\n", (uintptr_t)sd-(uintptr_t)scanarea + 0xE0000, sd->entry);

int bios32cs = __dpmi_create_alias_descriptor(_my_cs());
int bios32ds = __dpmi_create_alias_descriptor(_my_ds());
__dpmi_set_descriptor_access_rights(bios32cs, __dpmi_get_descriptor_access_rights(bios32cs)|0x08); //code/exec

uint32_t base = sd->entry&~0xFFF; //although it is physical addr, should be under 1M, phyiscal mapping not needed
__dpmi_set_segment_base_address(bios32cs, base);
__dpmi_set_segment_base_address(bios32ds, base);
__dpmi_set_segment_limit(bios32cs, 8192-1); //spec required 2 pages
__dpmi_set_segment_limit(bios32ds, 8192-1);
uint32_t pci32entry = 0;
uint32_t size = 0;
uint32_t eip = sd->entry - base;
free(scanarea);

_ASM_BEGINP
_ASM(pushad)
_ASM(push ds)

_ASM_MOVP(eax, %4) //bios32cs
_ASM(push eax)
_ASM_MOVP(eax, %5) //eip
_ASM(push eax)

_ASM(mov eax, 0x049435024) //$PCI
_ASM(xor ebx, ebx)

_ASM_MOVP(edx, %3) //bios32ds
_ASM(mov ds, edx)
_ASM(mov edx, esp)
_ASM(call far ptr ss:[edx])
_ASM(add esp, 8)
_ASM(pop ds)

_ASM(test al, al)
_ASM(jnz failed)
_ASM_MOVP(%0, ebx)
_ASM_MOVP(%1, ecx)
_ASM_MOVP(%2, edx)
_ASMLBL(failed:)
_ASM(popad)

_ASM_PLIST
_ASM_P _ASM_OP(base) _ASM_OP2(size) _ASM_OP2(pci32entry)
_ASM_P _ASM_IP(bios32ds) _ASM_IP2(bios32cs) _ASM_IP2(eip)
_ASM_P _ASM_CLOBBER(eax) _ASM_CLOBBER2(ebx) _ASM_CLOBBER2(ecx) _ASM_CLOBBER2(edx)
_ASM_ENDP
if(base == 0 || size == 0)
{
_LOG("32bit PCI BIOS not found.\n");
pds_dpmi_dos_freemem(&rmstack);
pds_dpmi_dos_freemem(&dosmem);
free(table);
return 0xFF;
}

_LOG("Found 32bit PCI BIOS, base: %x, entry %x, size: %x\n", base, pci32entry, size);
//const int CS_BASE = 0xF000; //spec required CS base //I think it's a typo in the spec
const int CS_BASE = 0xF0000;
size += max(CS_BASE - base, base - CS_BASE);
pci32entry += base;
base = CS_BASE;
pci32entry -= base;
__dpmi_set_segment_base_address(bios32cs, base);
__dpmi_set_segment_base_address(bios32ds, 0xF0000); //spec required DS base
__dpmi_set_segment_limit(bios32cs, size-1);
__dpmi_set_segment_limit(bios32ds, 64*1024-1); //spec required DS size
uint8_t errorcode = 0;

r.EAX = (PCI_FUNCTION_ID<<8)|PCI_SET_INTERRUPT;
r.ECX = (((uint32_t)irq)<<8) | (0xA + INTPIN - 1); //cl=INTPIN (0xA~0xD), ch=IRQ
r.EBX = (((uint32_t)ppkey->bBus)<<8) | ((ppkey->bDev<<3)&0xFF) | (ppkey->bFunc&0x7); //bh=bus, bl=dev|func
_LOG("EAX: %08lx, ECX: %08lx, EBX: %08lx\n", r.EAX, r.ECX, r.EBX);
_ASM_BEGINP
_ASM(pushad)
_ASM(push ds)

_ASM_MOVP(eax, %2) //bios32cs
_ASM(push eax)
_ASM_MOVP(eax, %3) //pci32entry
_ASM(push eax)

_ASM_MOVP(eax, %4)
_ASM_MOVP(ebx, %5)
_ASM_MOVP(ecx, %6)

_ASM_MOVP(edx, %1) //bios32ds
_ASM(mov ds, edx)
_ASM(mov edx, esp)
_ASM(call far ptr ss:[edx])
_ASM(add esp, 8)
_ASM(pop ds)

_ASM_MOVP(%0, ah)
_ASM(popad)

_ASM_PLIST
_ASM_P _ASM_OP(errorcode)
_ASM_P _ASM_IP(bios32ds) _ASM_IP2(bios32cs) _ASM_IP2(pci32entry) _ASM_IP2(r.EAX) _ASM_IP2(r.EBX) _ASM_IP2(r.ECX)
_ASM_P _ASM_CLOBBER(eax) _ASM_CLOBBER2(ebx) _ASM_CLOBBER2(ecx) _ASM_CLOBBER2(edx)
_ASM_ENDP
r.EAX = errorcode<<8;
__dpmi_free_ldt_descriptor(bios32ds);
__dpmi_free_ldt_descriptor(bios32cs);
#if USE_P32_CALL
#else
pds_dpmi_realmodeint_call(PCI_SERVICE, &r);
#endif

if(((r.EAX>>8)&0xFF) == PCI_SUCCESSFUL)
{
Expand Down Expand Up @@ -586,6 +740,7 @@ uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
else
{
_LOG("PCI_SET_INTERRUPT failed %x\n", ((r.EAX>>8)&0xFF));
PIC_SetIRQMask(irqmask);
irq = 0xFF;
}

Expand Down Expand Up @@ -619,4 +774,3 @@ uint8_t pcibios_AssignIRQ(pci_config_s* ppkey)
free(table);
return irq;
}
#undef BUFSIZE
27 changes: 25 additions & 2 deletions sbemu/platform.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@ static uint32_t PLTFM_BSF(uint32_t x) { uint32_t i; __asm {bsf eax, x; mov i, ea

//looks ugly. only if we can work preprocessing with raw string literals (R"()")
//raw string can work with preprocessor using gcc -E or cpp in the triditional way. need a special pass for file with asm
#define _ASM_BEGIN asm __volatile__(".intel_syntax noprefix\n\t"
#define _ASM_BEGIN __asm__ __volatile__(".intel_syntax noprefix\n\t"
#define _ASM_END ".att_syntax noprefix");
#define _ASM(...) #__VA_ARGS__"\n\t"
#define _ASMLBL _ASM
Expand All @@ -95,6 +95,17 @@ static uint32_t PLTFM_BSF(uint32_t x) { uint32_t i; __asm {bsf eax, x; mov i, ea
#define _ASM_END16 ".code32\n\t" _ASM_END
#define _ASM_BEGIN32 _ASM_BEGIN
#define _ASM_END32 _ASM_END
#define _ASM_MOVP(x,y) ".att_syntax noprefix\n\t" "mov "#y","#x"\n\t" ".intel_syntax noprefix\n\t"
#define _ASM_P :
#define _ASM_OP(x) "=m"(x)
#define _ASM_IP(x) "m"(x)
#define _ASM_OP2(x) ,"=m"(x)
#define _ASM_IP2(x) ,"m"(x)
#define _ASM_CLOBBER(x) #x
#define _ASM_CLOBBER2(x) ,#x
#define _ASM_PLIST ".att_syntax noprefix\n\t"
#define _ASM_BEGINP _ASM_BEGIN
#define _ASM_ENDP );

#define NOP() asm __volatile__("nop")
#define CLI() asm __volatile__("cli")
Expand Down Expand Up @@ -167,7 +178,19 @@ static inline uint16_t PLTFM_CPU_FLAGS() { uint16_t (* volatile VFN)(void) = &PL
#define _ASM_LIDT(x)
#define _ASM_LGDT(x)
#define _ASM_SIDT(x)
#define _ASM_SGDT(x)
#define _ASM_SGDT(x)

#define _ASM_PLIST
#define _ASM_P
#define _ASM_OP(x)
#define _ASM_IP(x)
#define _ASM_OP2(x)
#define _ASM_IP2(x)
#define _ASM_CLOBBER(x)
#define _ASM_CLOBBER2(x)
#define _ASM_MOVP(x,y)
#define _ASM_BEGINP {
#define _ASM_ENDP }

//not defined
extern void NOP();
Expand Down

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