X-Git-Url: http://git.joshuawise.com/netwatch.git/blobdiff_plain/ed22a6995cddb7b61503fdca859267ef85b3bdd3..5e93b6b390b19dcfe8dbd4bd8bfac37e50bab28f:/aseg-paging/pagingstub.c?ds=sidebyside diff --git a/aseg-paging/pagingstub.c b/aseg-paging/pagingstub.c index 0115713..7d430b9 100644 --- a/aseg-paging/pagingstub.c +++ b/aseg-paging/pagingstub.c @@ -5,6 +5,7 @@ #include #include #include +#include #include "traps.h" #include "../net/net.h" #include "vga-overlay.h" @@ -12,12 +13,10 @@ extern void smi_init(); #include "vm_flags.h" +extern void smi_entry(); void set_cr0(unsigned int); void ps_switch_stack (void (*call)(), int stack); -extern int entry_initialized; -extern int _bss, _bssend, _end; -void smi_entry(); #define get_cr0() \ ({ \ register unsigned int _temp__; \ @@ -35,107 +34,166 @@ void smi_entry(); #define MAP_FLAGS (PTE_PRESENT | PTE_READ_WRITE) -void * pt_setup(int smbase, int tseg_start, int tseg_size) { +static int initialized = 0; +static int paging_enb = 0; +static unsigned long *pd; + +extern int _bss, _bssend, _end; + +static unsigned long curmapped = 0xFFFFFFFF; + +unsigned long v2p(void *virt) +{ + unsigned long _virt = (unsigned long)virt; + + if (!paging_enb) + return _virt; + + if (_virt >= 0xA0000 && _virt < 0xC0000) + return _virt; + if (_virt >= 0x200000 && _virt < 0x300000) + return _virt - 0x200000 + /* XXX */ 0x1FF82000; + if (_virt >= 0x1F0000 && _virt < 0x1F2000) + return _virt - 0x1F0000 + 0x1FF80000; + if ((_virt & ~0xFFF) == 0x4000) + return _virt - 0x4000 + curmapped; + + outputf("WARNING: v2p(%08x)", _virt); + return 0xFFFFFFFF; +} + +void *p2v(unsigned long phys) +{ + if (!paging_enb) + return (void*)phys; + + if (phys >= 0xA0000 && phys < 0xC0000) + return (void*)phys; + if (phys >= 0x1FF82000 && phys < 0x20000000) + return (void*)(phys - 0x1FF82000 + 0x200000); + if (phys >= 0x1FF80000 && phys < 0x1FF82000) + return (void*)(phys - 0x1FF80000 + 0x1F0000); + + if ((phys & ~0xFFF) != curmapped) /* If it's not mapped, map it in. */ + { + curmapped = phys & ~0xFFF; + addmap(0x4000, curmapped); + asm volatile("invlpg 0x4000"); + } + return (void*)(0x4000 + (phys & 0xFFF)); +} + +int addmap(unsigned long vaddr, unsigned long paddr) +{ + unsigned long pde = ((unsigned long *)p2v((unsigned long)pd))[PDE_FOR(vaddr)]; + unsigned long *pt; + + if (!(pde & PTE_PRESENT)) + return -1; + + pt = (unsigned long *)p2v(ADDR_12_MASK(pde)); + pt[PTE_FOR(vaddr)] = paddr | PTE_PRESENT | PTE_READ_WRITE; + + return 0; +} + +void *demap(unsigned long client_pd, unsigned long vaddr) +{ + unsigned long pde = ((unsigned long *)p2v(client_pd))[PDE_FOR(vaddr)]; + unsigned long pte; + + if (!(pde & PTE_PRESENT)) + return (void*)0x0; + pte = ((unsigned long *)p2v(ADDR_12_MASK(pde)))[PTE_FOR(vaddr)]; + if (!(pte & PTE_PRESENT)) + return (void*)0x0; + return p2v((pte & ~0xFFF) + (vaddr & 0xFFF)); +} + +static void pt_setup(int tseg_start, int tseg_size) { int i; - outb(0x80, 0x51); - /* The page directory and page table live at SMBASE and SMBASE + 0x1000, - * respectively; clear them. */ - int * pagedirectory = (int *) tseg_start; - int * pagetable = (int *) (tseg_start + 0x1000); + /* The page directory and page table live at TSEG and TSEG + 0x1000, + * respectively. */ + unsigned long *pagedirectory = (unsigned long *) tseg_start; + unsigned long *pagetable = (unsigned long *) (tseg_start + 0x1000); + + pd = pagedirectory; /* Clear out the page directory except for one entry pointing to the * page table, and clear the page table entirely. */ - outb(0x80, 0x52); pagedirectory[0] = (tseg_start + 0x1000) | PTE_PRESENT | PTE_READ_WRITE; - outb(0x80, 0x53); for (i = 1; i < 1024; i++) - { pagedirectory[i] = 0; - } - outb(0x80, 0x54); for (i = 0; i < 1024; i++) - { pagetable[i] = 0; - } - outb(0x80, 0x55); - - /* The page at 0x10000 - 0x10FFF points to the SMI entry point, - * SMBASE + 0x8000. */ - pagetable[16] = (0x8000 + smbase) | MAP_FLAGS; - - /* 0x11000 to 0x1EFFF map to the rest of ASEG up to SMBASE + 0xF000; - * the page containing the saved state is not mappped to our code - * region. */ - - for (i = 0; i < 8; i++) - { - pagetable[17 + i] = (i * 0x1000 + smbase) | MAP_FLAGS; - } - - for (i = 0; i < 6; i++) - { - pagetable[25 + i] = (smbase + 0x9000 + i * 0x1000) | MAP_FLAGS; - } - - outb(0x80, 0x56); - /* Map 0xA8000 to itself. */ - for (i = 0; i < 32; i++) { - pagetable[0xA0 + i] = (0xA0000 + i * 0x1000) | MAP_FLAGS; - } + /* Map 0x0A0000:0x0BFFFF to itself. */ + for (i = 0; i < 32; i++) + addmap(0xA0000 + i * 0x1000, 0xA0000 + i * 0x1000); - /* Map 0x200000 to TSEG */ - for (i = 0; i < 128; i++) { - pagetable[0x200 + i] = (tseg_start + 0x2000 + i * 0x1000) | MAP_FLAGS; - } + /* Map 0x200000:0x300000 to TSEG data */ + for (i = 0; i < 256; i++) + addmap(0x200000 + i * 0x1000, tseg_start + (i + 2) * 0x1000); - /* Map 0x300000 -> 0x200000, so we can copy our code out of + /* Map 0x300000:0x400000 to 0x200000, so we can copy our code out of * RAM the first time around */ - for (i = 0; i < 256; i++) { - pagetable[0x300 + i] = (0x200000 + i * 0x1000) | MAP_FLAGS; - } + for (i = 0; i < 256; i++) + addmap(0x300000 + i * 0x1000, 0x200000 + i * 0x1000); - outb(0x80, 0x57); - return pagedirectory; + /* Map 0x1F0000:0x1F2000 to TSEG paging info */ + for (i = 0; i < 2; i++) + addmap(0x1F0000 + i * 0x1000, tseg_start + i * 0x1000); } void c_entry(void) { - unsigned char *bp; + paging_enb = 0; - outb(0x80, 0x41); - if (!entry_initialized) - pt_setup(0xA0000, 0x1FF80000, 0x80000); + outb(0x80, 0x01); + if (!initialized) + pt_setup(0x1FF80000, 0x80000); + outb(0x80, 0x02); /* Enable paging. */ - outb(0x80, 0x42); - set_cr3(0x1FF80000); + set_cr3((unsigned long)pd); set_cr0(get_cr0() | CR0_PG); - - outb(0x80, 0x43); + outb(0x80, 0x03); + paging_enb = 1; - if (!entry_initialized) { + /* If this is the first goround, copy in data. */ + if (!initialized) + { + unsigned char *p; - /* If needed, copy in data. */ - for (bp = (void *)0x200000; (void *)bp < (void *)&_bss; bp++) - *bp = *(bp + 0x100000); - for (bp = (void *)&_bss; (void *)bp < (void *)&_bssend; bp++) - *bp = 0; + outb(0x80, 0x04); + for (p = (void *)0x200000; (void *)p < (void *)&_bss; p++) + *p = *(p + 0x100000); + for (p = (void *)&_bss; (void *)p < (void *)&_bssend; p++) + *p = 0; + outb(0x80, 0x05); + + /* Only now is it safe to call other functions. */ serial_init(); - dolog("Paging enabled."); + dolog("Evacuation to TSEG complete."); } + + outb(0x80, 0x06); traps_install(); + + outb(0x80, 0x07); - if (!entry_initialized) { - smi_init(); + if (!initialized) + { + smi_init(); /* Run the firstrun. */ + outb(0x80, 0x08); - entry_initialized = 1; + initialized = 1; } - - outb(0x80, 0x44); + + outb(0x80, 0x09); ps_switch_stack(smi_entry, 0x270000); outb(0x80, 0xFA); }