Changeset 3cc110f in mainline

Timestamp:

2009-10-22T17:35:18Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

5328d63

Parents:

8e000b8d

Message:

Autodetect SYSENTER support in uspace.

Files:

• kernel/arch/ia32/src/userspace.c (modified) (1 diff)
• uspace/lib/libc/arch/ia32/src/entry.s (modified) (3 diffs)
• uspace/srv/loader/arch/ia32/ia32.s (modified) (1 diff)

kernel/arch/ia32/src/userspace.c

@@ -70 +70 @@
                 "movl %[uarg], %%eax\n"
                 
-                /* %ebx is defined to hold pcb_ptr - set it to 0 */
-                "xorl %%ebx, %%ebx\n"
+                /* %edi is defined to hold pcb_ptr - set it to 0 */
+                "xorl %%edi, %%edi\n"
                 
                 "iret\n"

uspace/lib/libc/arch/ia32/src/entry.s

@@ -27 +27 @@
 #
 
+INTEL_CPUID_STANDARD = 1
+INTEL_SEP = 11
+
 .section .init, "ax"
 
@@ -35 +38 @@
 ## User-space task entry point
 #
-# %ebx contains the PCB pointer
+# %edi contains the PCB pointer
 #
 __entry:
@@ -44 +47 @@
         # Do not set %gs, it contains descriptor that can see TLS
 
+        # Detect the mechanism used for making syscalls
+        movl $(INTEL_CPUID_STANDARD), %eax
+        cpuid
+        bt $(INTEL_SEP), %edx
+        jnc 0f
+        leal __syscall_fast_func, %eax
+        movl $__syscall_fast, (%eax)
+0:
+
         # Pass the PCB pointer to __main as the first argument
-        pushl %ebx
+        pushl %edi
         call __main
 

uspace/srv/loader/arch/ia32/ia32.s

@@ -40 +40 @@
         movl 0x8(%ebp), %eax
 
-        # %ebx := pcb
-        # pcb is passed to the entry point int %ebx
-        mov 0xc(%ebp), %ebx
+        # %edi := pcb
+        # pcb is passed to the entry point in %edi
+        mov 0xc(%ebp), %edi
 
         # Save a tiny bit of stack space