microblaze: Save and restore r3/r4 in SAVE/RESTORE_REGS macros
Save and restore R3/R4 registers in macros. This change
help to cleanup entry.S.
In ret_from_trap function we are saving returning value from
syscall to pt_regs on stack that's why we don't need to save and
restore these values before kernel functions (schedule, do_signal).
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S
index d40a59f..8f90ce7 100644
--- a/arch/microblaze/kernel/entry.S
+++ b/arch/microblaze/kernel/entry.S
@@ -194,6 +194,8 @@
#define SAVE_REGS \
swi r2, r1, PTO+PT_R2; /* Save SDA */ \
+ swi r3, r1, PTO+PT_R3; \
+ swi r4, r1, PTO+PT_R4; \
swi r5, r1, PTO+PT_R5; \
swi r6, r1, PTO+PT_R6; \
swi r7, r1, PTO+PT_R7; \
@@ -228,6 +230,8 @@
mts rmsr , r11; \
nop; \
lwi r2, r1, PTO+PT_R2; /* restore SDA */ \
+ lwi r3, r1, PTO+PT_R3; \
+ lwi r4, r1, PTO+PT_R4; \
lwi r5, r1, PTO+PT_R5; \
lwi r6, r1, PTO+PT_R6; \
lwi r7, r1, PTO+PT_R7; \
@@ -379,13 +383,12 @@
/* We re-enable BIP bit before state restore */
C_ENTRY(ret_from_trap):
set_bip; /* Ints masked for state restore*/
- lwi r11, r1, PTO+PT_MODE;
-/* See if returning to kernel mode, if so, skip resched &c. */
- bnei r11, 2f;
-
swi r3, r1, PTO + PT_R3
swi r4, r1, PTO + PT_R4
+ lwi r11, r1, PTO+PT_MODE;
+/* See if returning to kernel mode, if so, skip resched &c. */
+ bnei r11, 2f;
/* We're returning to user mode, so check for various conditions that
* trigger rescheduling. */
/* FIXME: Restructure all these flag checks. */
@@ -422,9 +425,6 @@
/* Finally, return to user state. */
1:
- lwi r3, r1, PTO + PT_R3; /* restore syscall result */
- lwi r4, r1, PTO + PT_R4;
-
swi r0, r0, PER_CPU(KM); /* Now officially in user state. */
swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE); /* save current */
VM_OFF;
@@ -522,10 +522,6 @@
swi r11, r1, (PT_R1-PT_SIZE); /* Save original SP. */ \
lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */\
addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\
- /* store return registers separately because \
- * this macros is use for others exceptions */ \
- swi r3, r1, PTO + PT_R3; \
- swi r4, r1, PTO + PT_R4; \
SAVE_REGS \
/* PC, before IRQ/trap - this is one instruction above */ \
swi r17, r1, PTO+PT_PC; \
@@ -543,10 +539,6 @@
tophys(r1,r1); \
\
addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */\
- /* store return registers separately because this macros \
- * is use for others exceptions */ \
- swi r3, r1, PTO + PT_R3; \
- swi r4, r1, PTO + PT_R4; \
SAVE_REGS \
/* PC, before IRQ/trap - this is one instruction above FIXME*/ \
swi r17, r1, PTO+PT_PC; \
@@ -689,9 +681,7 @@
* traps), but signal handlers may want to examine or change the
* complete register state. Here we save anything not saved by
* the normal entry sequence, so that it may be safely restored
- * (in a possibly modified form) after do_signal returns.
- * store return registers separately because this macros is use
- * for others exceptions */
+ * (in a possibly modified form) after do_signal returns. */
la r5, r1, PTO; /* Arg 1: struct pt_regs *regs */
addi r7, r0, 0; /* Arg 3: int in_syscall */
bralid r15, do_signal; /* Handle any signals */
@@ -703,8 +693,6 @@
VM_OFF;
tophys(r1,r1);
- lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */
- lwi r4, r1, PTO+PT_R4;
RESTORE_REGS;
addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */
@@ -713,8 +701,6 @@
/* Return to kernel state. */
2: VM_OFF;
tophys(r1,r1);
- lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */
- lwi r4, r1, PTO+PT_R4;
RESTORE_REGS;
addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */
@@ -753,10 +739,6 @@
/* save registers */
/* MS: Make room on the stack -> activation record */
addik r1, r1, -STATE_SAVE_SIZE;
-/* MS: store return registers separately because
- * this macros is use for others exceptions */
- swi r3, r1, PTO + PT_R3;
- swi r4, r1, PTO + PT_R4;
SAVE_REGS
/* MS: store mode */
addi r11, r0, 1; /* MS: Was in kernel-mode. */
@@ -776,8 +758,6 @@
tophys(r1,r1);
/* save registers */
addik r1, r1, -STATE_SAVE_SIZE;
- swi r3, r1, PTO+PT_R3;
- swi r4, r1, PTO+PT_R4;
SAVE_REGS
/* calculate mode */
swi r0, r1, PTO + PT_MODE;
@@ -829,8 +809,6 @@
swi CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE);
VM_OFF;
tophys(r1,r1);
- lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */
- lwi r4, r1, PTO + PT_R4;
RESTORE_REGS
addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */
lwi r1, r1, PT_R1 - PT_SIZE;
@@ -859,8 +837,6 @@
#endif
VM_OFF /* MS: turn off MMU */
tophys(r1,r1)
- lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */
- lwi r4, r1, PTO + PT_R4;
RESTORE_REGS
addik r1, r1, STATE_SAVE_SIZE /* MS: Clean up stack space. */
tovirt(r1,r1);
@@ -893,8 +869,6 @@
lwi r11, r0, TOPHYS(r0_ram + PTO + PT_R11); /* restore r11 */
addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */
- swi r3, r1, PTO + PT_R3;
- swi r4, r1, PTO + PT_R4;
SAVE_REGS;
addi r11, r0, 1; /* Was in kernel-mode. */
@@ -910,8 +884,6 @@
tophys(r1,r1);
addik r1, r1, -STATE_SAVE_SIZE; /* Make room on the stack. */
- swi r3, r1, PTO + PT_R3;
- swi r4, r1, PTO + PT_R4;
SAVE_REGS;
swi r0, r1, PTO+PT_MODE; /* Was in user-mode. */
@@ -979,8 +951,6 @@
VM_OFF;
tophys(r1,r1);
- lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */
- lwi r4, r1, PTO+PT_R4;
RESTORE_REGS
addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */
@@ -992,8 +962,6 @@
/* Return to kernel state. */
2: VM_OFF;
tophys(r1,r1);
- lwi r3, r1, PTO+PT_R3; /* restore saved r3, r4 registers */
- lwi r4, r1, PTO+PT_R4;
RESTORE_REGS
addik r1, r1, STATE_SAVE_SIZE /* Clean up stack space. */