s390/boot: Convert cmma_test_essa() to extable

Shorten cmma_test_essa() and use regular EX_TABLE program check handling.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 98649e5049895dc08052e733e032b04fc5d1394d..978a779a6d47c027d7b9ceb0103a21e37ae21b42 100644 (file)
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -147,30 +147,17 @@ static void detect_facilities(void)
 
 static int cmma_test_essa(void)
 {
-       unsigned long reg1, reg2, tmp = 0;
+       unsigned long tmp = 0;
        int rc = 1;
-       psw_t old;
 
        /* Test ESSA_GET_STATE */
        asm volatile(
-               "       mvc     0(16,%[psw_old]),0(%[psw_pgm])\n"
-               "       epsw    %[reg1],%[reg2]\n"
-               "       st      %[reg1],0(%[psw_pgm])\n"
-               "       st      %[reg2],4(%[psw_pgm])\n"
-               "       larl    %[reg1],1f\n"
-               "       stg     %[reg1],8(%[psw_pgm])\n"
                "       .insn   rrf,0xb9ab0000,%[tmp],%[tmp],%[cmd],0\n"
-               "       la      %[rc],0\n"
-               "1:     mvc     0(16,%[psw_pgm]),0(%[psw_old])\n"
-               : [reg1] "=&d" (reg1),
-                 [reg2] "=&a" (reg2),
-                 [rc] "+&d" (rc),
-                 [tmp] "=&d" (tmp),
-                 "+Q" (get_lowcore()->program_new_psw),
-                 "=Q" (old)
-               : [psw_old] "a" (&old),
-                 [psw_pgm] "a" (&get_lowcore()->program_new_psw),
-                 [cmd] "i" (ESSA_GET_STATE)
+               "0:     lhi     %[rc],0\n"
+               "1:\n"
+               EX_TABLE(0b, 1b)
+               : [rc] "+d" (rc), [tmp] "+d" (tmp)
+               : [cmd] "i" (ESSA_GET_STATE)
                : "cc", "memory");
        return rc;
 }