Re: [coreboot] r964 - coreboot-v3/util/x86emu

[Jordan Crouse]

On 29/10/08 15:00 -0600, Myles Watson wrote:
> > Modified:
> >   coreboot-v3/util/x86emu/vm86.c
> > Log:
> > This patch makes the vm86 call succeed. It
> > moves the run_bios function down so it can call setup_realmode_idt
> > adds the __attribute__((regnum(0))) to biosint because it is called from
> >
> > assembly
>
> Anybody who wants to test this in SimNOW either needs to unshare pci and
> printk, or remove calls into the ROM while the VGA ROM is running.
> Otherwise when the ROM gets sized, your code disappears.
>
> Signed-off-by: Myles Watson

We already have Simnow ifdefs in the code - would those help to make 
the code work out of the box?

Jordan
> Thanks,l
> Myles
> Index: util/x86emu/vm86.c
>
> --- util/x86emu/vm86.c	(revision 964)
> +++ util/x86emu/vm86.c	(working copy)
> @@ -29,6 +29,8 @@
>  #include <string.h>
>  #include <io.h>
>
> +#define CONFIG_CMD(bdf, where)   (0x80000000 | (bdf) | ((where & 0xff) & ~3) | ((where & 0xf00)<<16) )
>
> /* The address arguments to this function are PHYSICAL ADDRESSES */
>  static void real_mode_switch_call_vga(unsigned long devfn)
>  {
> @@ -418,28 +420,15 @@
>    cs = cs_ip >> 16;
>    flags = stackflags;
> printk(BIOS_DEBUG, "biosint: INT# 0x%lx\n", intnumber);
> printk(BIOS_DEBUG, "biosint: eax 0x%lx ebx 0x%lx ecx 0x%lx edx 0x%lx\n",
>       eax, ebx, ecx, edx);
> printk(BIOS_DEBUG, "biosint: ebp 0x%lx esp 0x%lx edi 0x%lx esi 0x%lx\n",
>      ebp, esp, edi, esi);
> printk(BIOS_DEBUG, "biosint:  ip 0x%lx   cs 0x%lx  flags 0x%lx\n",
>      ip, cs, flags);
> // cases in a good compiler are just as good as your own tables.
>  switch (intnumber) {
>  case 0 ... 15:
>   // These are not BIOS service, but the CPU-generated exceptions
> printk(BIOS_INFO, "biosint: Oops, exception %lu\n", intnumber);
> if (esp < 0x1000) {
> 	printk(BIOS_DEBUG, "Stack contents: ");
> while (esp < 0x1000) {
> 		printk(BIOS_DEBUG, "0x%04x ", *(unsigned short *) esp);
> 	esp += 2;
> }
> 	printk(BIOS_DEBUG, "\n");
> }
> printk(BIOS_DEBUG, "biosint: Bailing out\n");
> // "longjmp"
> vga_exit();
> break;
>
> @@ -458,8 +447,6 @@
>    			&ebx, &edx, &ecx, &eax, &flags);
>    	break;
>    default:
> printk(BIOS_INFO, "BIOSINT: Unsupport int #0x%lx\n",
> 	    intnumber);
> break;
> }
> if (ret)
>
> @@ -598,7 +585,6 @@
>    		// devfn is an int, so we mask it off.
>    		busdevfn = (dev->bus->secondary << 8)
>    			| (dev->path.pci.devfn & 0xff);
> 	printk(BIOS_DEBUG, "0x%x: return 0x%x\n", func, busdevfn);
> *pebx = busdevfn;
> retval = 0;
> } else {
>
> @@ -618,54 +604,74 @@
>    	unsigned short word;
>    	unsigned char byte;
>    	unsigned char reg;
> struct bus *pbus;
>
> devfn = *pebx & 0xff;
> bus = *pebx >> 8;
> reg = *pedi;
> dev = dev_find_slot(bus, devfn);
> if (! dev) {
> 	printk(BIOS_DEBUG, "0x%x: BAD DEVICE bus %d devfn 0x%x\n", func, bus, devfn);
> // idiots. the pcibios guys assumed you'd never pass a bad bus/devfn!
> *peax = PCIBIOS_BADREG;
> retval = -1;
> }
> pbus = dev->bus;
> while (pbus && pbus->dev && !ops_pci_bus(pbus)) {
> 	pbus = pbus->dev->bus;
> }
> switch(func) {
> case READCONFBYTE:
> 	byte = pci_read_config8(dev, reg);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn),
> 			reg),
> 		0xCF8);
> 	byte =  inb(0xCFC + (reg & 3));
> *pecx = byte;
> break;
> case READCONFWORD:
> 	word = pci_read_config16(dev, reg);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn), reg),
> 		0xCF8);
> 	word = inw(0xCFC + (reg & 2));
> *pecx = word;
> break;
> case READCONFDWORD:
> 	dword = pci_read_config32(dev, reg);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn), reg),
> 		0xCF8);
> 	dword = inl(0xCFC);
> *pecx = dword;
> break;
> case WRITECONFBYTE:
> 	byte = *pecx;
> 	pci_write_config8(dev, reg, byte);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn), reg),
> 		0xCF8);
> 	outb(byte, 0xCFC + (reg & 3));
> break;
> case WRITECONFWORD:
> 	word = *pecx;
> 	pci_write_config16(dev, reg, word);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn), reg),
> 		0xCF8);
> 	outw(word, 0xCFC + (reg & 2));
> break;
> case WRITECONFDWORD:
> 	dword = *pecx;
> 	pci_write_config32(dev, reg, dword);
> 	outl(CONFIG_CMD(PCI_BDEVFN(dev->bus->secondary,
> 				   dev->path.pci.devfn), reg),
> 		0xCF8);
> 	outl(dword, 0xCFC);
> break;
>
> }
>
> if (retval)
> 	retval = PCIBIOS_BADREG;
> printk(BIOS_DEBUG, "0x%x: bus %d devfn 0x%x reg 0x%x val 0x%lx\n",
> 	     func, bus, devfn, reg, *pecx);
> *peax = 0;
> retval = 0;
> }
> break;
> default:
> printk(BIOS_ERR, "UNSUPPORTED PCIBIOS FUNCTION 0x%x\n",  func);
> break;
> }
>