adding a bunch of code (vesa, keyb, mouse, etc) to the menu

[cdmenu] / menu / src / dos / cdpmi.c

diff --git a/menu/src/dos/cdpmi.c b/menu/src/dos/cdpmi.c
new file mode 100644 (file)
index 0000000..9ffb8c6
--- /dev/null
+++ b/menu/src/dos/cdpmi.c
@@ -0,0 +1,103 @@
+#include <stdio.h>
+#include <i86.h>
+#include "cdpmi.h"
+#include "logger.h"
+
+#define LOWBUF_SIZE            8192
+#define RMSTACK_SIZE   4096
+
+static char *lowbuf, *lowfree;
+static uint16_t lowbuf_sel, lowbuf_seg;
+
+int dpmi_init(void)
+{
+       if(!(lowbuf_seg = dpmi_alloc(LOWBUF_SIZE >> 4, &lowbuf_sel))) {
+               errormsg("DPMI init failed to allocate low memory buffer\n");
+               return -1;
+       }
+       lowbuf = (char*)((intptr_t)lowbuf_seg << 4);
+       lowfree = lowbuf + RMSTACK_SIZE;
+       return 0;
+}
+
+void dpmi_cleanup(void)
+{
+       if(!lowbuf_sel) return;
+       dpmi_free(lowbuf_sel);
+       lowbuf = 0;
+       lowbuf_sel = 0;
+       lowbuf_seg = 0;
+}
+
+void *dpmi_lowbuf(void)
+{
+       return lowfree;
+}
+
+uint16_t dpmi_alloc(unsigned int par, uint16_t *sel)
+{
+       union REGS regs = {0};
+
+       regs.w.ax = 0x100;
+       regs.w.bx = par;
+       int386(0x31, &regs, &regs);
+       if(regs.w.cflag != 0) {
+               return 0;
+       }
+       *sel = regs.w.dx;
+       return regs.w.ax;
+}
+
+void dpmi_free(uint16_t sel)
+{
+       union REGS regs = {0};
+
+       regs.w.ax = 0x101;
+       regs.w.dx = sel;
+       int386(0x31, &regs, &regs);
+}
+
+int dpmi_rmint(int inum, struct dpmi_regs *dregs)
+{
+       union REGS regs = {0};
+       struct SREGS sregs = {0};
+
+       regs.x.eax = 0x300;
+       regs.x.ebx = inum;
+       sregs.es = FP_SEG(dregs);
+       regs.x.edi = FP_OFF(dregs);
+       sregs.ss = lowbuf_seg;  /* 4k real mode stack */
+       int386x(0x31, &regs, &regs, &sregs);
+       if(regs.x.cflag != 0) {
+               return -1;
+       }
+       return 0;
+}
+
+void *dpmi_mmap(uint32_t phys_addr, unsigned int size)
+{
+       union REGS regs = {0};
+
+       regs.w.ax = 0x800;
+       regs.w.bx = phys_addr >> 16;
+       regs.w.cx = phys_addr & 0xffff;
+       regs.w.si = size >> 16;
+       regs.w.di = size & 0xffff;
+       int386(0x31, &regs, &regs);
+       if(regs.w.cflag != 0) {
+               return 0;
+       }
+
+       return (void*)(((intptr_t)regs.w.bx << 16) | (intptr_t)regs.w.cx);
+}
+
+void dpmi_munmap(void *ptr)
+{
+       union REGS regs = {0};
+       intptr_t addr = (intptr_t)ptr;
+
+       regs.w.ax = 0x801;
+       regs.w.bx = addr >> 16;
+       regs.w.cx = addr & 0xffff;
+       int386(0x31, &regs, &regs);
+}