microblaze: Completely remove working with R11 register

We don't need to save R11 register. There is easy way
to use only R1 which is saved and restore later.

Signed-off-by: Michal Simek <monstr@monstr.eu>

diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index 1f40280..9b8e072 100644 (file)
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -273,18 +273,15 @@
 C_ENTRY(_user_exception):
        swi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP)) /* save stack */
        addi    r14, r14, 4     /* return address is 4 byte after call */
-       swi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */
 
-       mfs     r11, rmsr
+       mfs     r1, rmsr
        nop
-       andi    r11, r11, MSR_UMS
-       bnei    r11, 1f
+       andi    r1, r1, MSR_UMS
+       bnei    r1, 1f
 
 /* Kernel-mode state save - kernel execve */
-       lwi     r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
-       tophys(r1,r11);
-       swi     r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */
+       lwi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
+       tophys(r1,r1);
 
        addik   r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */
        SAVE_REGS
@@ -296,7 +293,6 @@ C_ENTRY(_user_exception):
 
 /* User-mode state save.  */
 1:
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */
        lwi     r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */
        tophys(r1,r1);
        lwi     r1, r1, TS_THREAD_INFO; /* get stack from task_struct */
@@ -506,18 +502,15 @@ C_ENTRY(sys_rt_sigreturn_wrapper):
 
 #define SAVE_STATE     \
        swi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* save stack */     \
-       swi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */  \
        /* See if already in kernel mode.*/                             \
-       mfs     r11, rmsr;                                              \
+       mfs     r1, rmsr;                                               \
        nop;                                                            \
-       andi    r11, r11, MSR_UMS;                                      \
-       bnei    r11, 1f;                                                \
+       andi    r1, r1, MSR_UMS;                                        \
+       bnei    r1, 1f;                                         \
        /* Kernel-mode state save.  */                                  \
        /* Reload kernel stack-ptr. */                                  \
-       lwi     r11, r0, TOPHYS(PER_CPU(ENTRY_SP));                     \
-       tophys(r1,r11);                                                 \
-       swi     r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */       \
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\
+       lwi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP));                      \
+       tophys(r1,r1);                                                  \
        addik   r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack.  */\
        SAVE_REGS                                                       \
        /* PC, before IRQ/trap - this is one instruction above */       \
@@ -528,13 +521,11 @@ C_ENTRY(sys_rt_sigreturn_wrapper):
        brid    2f;                                                     \
        nop;                            /* Fill delay slot */           \
 1:     /* User-mode state save.  */                                    \
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\
        lwi     r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\
        tophys(r1,r1);                                                  \
        lwi     r1, r1, TS_THREAD_INFO; /* get the thread info */       \
        addik   r1, r1, THREAD_SIZE;    /* calculate kernel stack pointer */\
        tophys(r1,r1);                                                  \
-                                                                       \
        addik   r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack.  */\
        SAVE_REGS                                                       \
        /* PC, before IRQ/trap - this is one instruction above FIXME*/  \
@@ -726,20 +717,15 @@ C_ENTRY(_interrupt):
 /* MS: we are in physical address */
 /* Save registers, switch to proper stack, convert SP to virtual.*/
        swi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
-       swi     r11, r0, TOPHYS(PER_CPU(R11_SAVE));
        /* MS: See if already in kernel mode. */
-       mfs     r11, rmsr
+       mfs     r1, rmsr
        nop
-       andi    r11, r11, MSR_UMS
-       bnei    r11, 1f
+       andi    r1, r1, MSR_UMS
+       bnei    r1, 1f
 
 /* Kernel-mode state save. */
-       or      r11, r1, r0
-       tophys(r1,r11); /* MS: I have in r1 physical address where stack is */
-/* MS: Save original SP - position PT_R1 to next stack frame 4 *1 - 152*/
-       swi     r11, r1, (PT_R1 - PT_SIZE);
-/* MS: restore r11 because of saving in SAVE_REGS */
-       lwi     r11, r0, TOPHYS(PER_CPU(R11_SAVE));
+       lwi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
+       tophys(r1,r1); /* MS: I have in r1 physical address where stack is */
        /* save registers */
 /* MS: Make room on the stack -> activation record */
        addik   r1, r1, -STATE_SAVE_SIZE;
@@ -752,8 +738,6 @@ C_ENTRY(_interrupt):
 
 1:
 /* User-mode state save. */
-/* MS: restore r11 -> FIXME move before SAVE_REG */
-       lwi     r11, r0, TOPHYS(PER_CPU(R11_SAVE));
  /* MS: get the saved current */
        lwi     r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
        tophys(r1,r1);
@@ -855,16 +839,13 @@ C_ENTRY(_debug_exception):
        /* BIP bit is set on entry, no interrupts can occur */
        swi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP))
 
-       swi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* Save r11 */
-       mfs     r11, rmsr
+       mfs     r1, rmsr
        nop
-       andi    r11, r11, MSR_UMS
-       bnei    r11, 1f
+       andi    r1, r1, MSR_UMS
+       bnei    r1, 1f
        /* Kernel-mode state save.  */
-       lwi     r11, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
-       tophys(r1,r11);
-       swi     r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */
+       lwi     r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
+       tophys(r1,r1);
 
        addik   r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack.  */
        SAVE_REGS;
@@ -874,7 +855,6 @@ C_ENTRY(_debug_exception):
        brid    2f;
        nop;                            /* Fill delay slot */
 1:      /* User-mode state save.  */
-       lwi     r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */
        lwi     r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */
        tophys(r1,r1);
        lwi     r1, r1, TS_THREAD_INFO; /* get the thread info */
@@ -887,7 +867,7 @@ C_ENTRY(_debug_exception):
        swi     r0, r1, PTO+PT_MODE; /* Was in user-mode.  */
        lwi     r11, r0, TOPHYS(PER_CPU(ENTRY_SP));
        swi     r11, r1, PTO+PT_R1; /* Store user SP.  */
-2:     lwi     CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));
+2:
        /* Save away the syscall number.  */
        swi     r0, r1, PTO+PT_R0;
        tovirt(r1,r1)