diff options
Diffstat (limited to 'payloads/libpayload/i386/head.S')
| -rw-r--r-- | payloads/libpayload/i386/head.S | 47 |
1 files changed, 21 insertions, 26 deletions
diff --git a/payloads/libpayload/i386/head.S b/payloads/libpayload/i386/head.S index 1278bdf4ed..e05cb3ed30 100644 --- a/payloads/libpayload/i386/head.S +++ b/payloads/libpayload/i386/head.S @@ -26,60 +26,55 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ - + .global _entry, _leave .text .align 4 -/* Our entry point - assume that the CPU is in - * 32 bit protected mode and all segments are in a - * flat model. Thats our operating mode, so we won't - * change anything +/* + * Our entry point - assume that the CPU is in 32 bit protected mode and + * all segments are in a flat model. That's our operating mode, so we won't + * change anything. */ - _entry: call _init - /* We're back - go back to the bootloader */ + /* We're back - go back to the bootloader. */ ret -/* This function saves off the previous stack and - switches us to our own execution enviornment -*/ - +/* + * This function saves off the previous stack and switches us to our + * own execution environment. + */ _init: - /* No interrupts, please */ + /* No interrupts, please. */ cli - /* Get the current stack pointer */ + /* Get the current stack pointer. */ movl %esp, %esi movl _istack, %ebx - /* lret needs %cs in the stack, so copy it over */ + /* lret needs %cs in the stack, so copy it over. */ movw %cs, 4(%ebx) - /* Exchange the current stack pointer for the one in - the initial stack (which happens to be the new - stack pointer) */ - + /* + * Exchange the current stack pointer for the one in the initial + * stack (which happens to be the new stack pointer). + */ xchgl %esi, 16(%ebx) - /* Set the new stack pointer */ + /* Set the new stack pointer. */ movl %esi, %esp - /* Return into the main entry function - and go - */ - + /* Return into the main entry function and go. */ lret _leave: movl _istack, %ebx - /* Restore the stack pointer from the storage area */ + /* Restore the stack pointer from the storage area. */ movl 16(%ebx), %esp - /* Return to the original context */ + /* Return to the original context. */ lret - |