preserve partition table when using -linux option

[qemu] / hw / pc.c

diff --git a/hw/pc.c b/hw/pc.c
index 5431a41..d0fcb0f 100644 (file)
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -76,6 +76,10 @@ static void cmos_init(int ram_size, int boot_device)
     /* various important CMOS locations needed by PC/Bochs bios */
 
     /* memory size */
+    val = 640; /* base memory in K */
+    rtc_set_memory(s, 0x15, val);
+    rtc_set_memory(s, 0x16, val >> 8);
+
     val = (ram_size / 1024) - 1024;
     if (val > 65535)
         val = 65535;
@@ -177,6 +181,17 @@ static uint32_t speaker_ioport_read(void *opaque, uint32_t addr)
       (dummy_refresh_clock << 4);
 }
 
+static void ioport92_write(void *opaque, uint32_t addr, uint32_t val)
+{
+    cpu_x86_set_a20(cpu_single_env, (val >> 1) & 1);
+    /* XXX: bit 0 is fast reset */
+}
+
+static uint32_t ioport92_read(void *opaque, uint32_t addr)
+{
+    return ((cpu_single_env->a20_mask >> 20) & 1) << 1;
+}
+
 /***********************************************************/
 /* Bochs BIOS debug ports */
 
@@ -291,12 +306,14 @@ void pc_init(int ram_size, int vga_ram_size, int boot_device,
     
     /* setup basic memory access */
     cpu_register_physical_memory(0xc0000, 0x10000, 0xc0000 | IO_MEM_ROM);
+    cpu_register_physical_memory(0xd0000, 0x20000, IO_MEM_UNASSIGNED);
     cpu_register_physical_memory(0xf0000, 0x10000, 0xf0000 | IO_MEM_ROM);
     
     bochs_bios_init();
 
     if (linux_boot) {
         uint8_t bootsect[512];
+        uint8_t old_bootsect[512];
 
         if (bs_table[0] == NULL) {
             fprintf(stderr, "A disk image must be given for 'hda' when booting a Linux kernel\n");
@@ -310,6 +327,11 @@ void pc_init(int ram_size, int vga_ram_size, int boot_device,
             exit(1);
         }
 
+        if (bdrv_read(bs_table[0], 0, old_bootsect, 1) >= 0) {
+            /* copy the MSDOS partition table */
+            memcpy(bootsect + 0x1be, old_bootsect + 0x1be, 0x40);
+        }
+
         bdrv_set_boot_sector(bs_table[0], bootsect, sizeof(bootsect));
 
         /* now we can load the kernel */
@@ -355,6 +377,9 @@ void pc_init(int ram_size, int vga_ram_size, int boot_device,
     register_ioport_read(0x61, 1, 1, speaker_ioport_read, NULL);
     register_ioport_write(0x61, 1, 1, speaker_ioport_write, NULL);
 
+    register_ioport_read(0x92, 1, 1, ioport92_read, NULL);
+    register_ioport_write(0x92, 1, 1, ioport92_write, NULL);
+
     pic_init();
     pit_init(0x40, 0);