Patched in Tegra support.

1 files changed, 44 insertions, 35 deletions

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index 5e5b30601bb..d5f9c35a583 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -95,6 +95,7 @@ handler:							;\
         /* r1, EPCR, ESR a already saved */                     ;\
         l.sw    PT_GPR2(r1),r2                                  ;\
         l.sw    PT_GPR3(r1),r3                                  ;\
+        l.sw    PT_ORIG_GPR11(r1),r11                           ;\
         /* r4 already save */                                   ;\
         l.sw    PT_GPR5(r1),r5                                  ;\
         l.sw    PT_GPR6(r1),r6                                  ;\
@@ -124,9 +125,7 @@ handler:							;\
         /* r30 already save */                                  ;\
 /*        l.sw    PT_GPR30(r1),r30*/                                    ;\
         l.sw    PT_GPR31(r1),r31                                        ;\
-        /* Store -1 in orig_gpr11 for non-syscall exceptions */ ;\
-        l.addi  r30,r0,-1                                       ;\
-        l.sw    PT_ORIG_GPR11(r1),r30
+        l.sw    PT_SYSCALLNO(r1),r0
 
 #define UNHANDLED_EXCEPTION(handler,vector)                     \
         .global handler                                         ;\
@@ -134,6 +133,7 @@ handler:							;\
         /* r1, EPCR, ESR already saved */                       ;\
         l.sw    PT_GPR2(r1),r2                                  ;\
         l.sw    PT_GPR3(r1),r3                                  ;\
+        l.sw    PT_ORIG_GPR11(r1),r11                           ;\
         l.sw    PT_GPR5(r1),r5                                  ;\
         l.sw    PT_GPR6(r1),r6                                  ;\
         l.sw    PT_GPR7(r1),r7                                  ;\
@@ -162,9 +162,7 @@ handler:							;\
         /* r31 already saved */                                 ;\
         l.sw    PT_GPR30(r1),r30                                        ;\
 /*        l.sw    PT_GPR31(r1),r31      */                              ;\
-        /* Store -1 in orig_gpr11 for non-syscall exceptions */ ;\
-        l.addi  r30,r0,-1                                       ;\
-        l.sw    PT_ORIG_GPR11(r1),r30                           ;\
+        l.sw    PT_SYSCALLNO(r1),r0                             ;\
         l.addi  r3,r1,0                                         ;\
         /* r4 is exception EA */                                ;\
         l.addi  r5,r0,vector                                    ;\
@@ -556,7 +554,6 @@ ENTRY(_sys_call_handler)
         l.sw    PT_GPR9(r1),r9
         /* r10 already saved */
         l.sw    PT_GPR11(r1),r11
-        /* orig_gpr11 must be set for syscalls */
         l.sw    PT_ORIG_GPR11(r1),r11
         /* r12,r13 already saved */
 
@@ -570,6 +567,9 @@ ENTRY(_sys_call_handler)
         /* r30 is the only register we clobber in the fast path */
         /* r30 already saved */
 /*      l.sw    PT_GPR30(r1),r30 */
+        /* This is used by do_signal to determine whether to check for
+         * syscall restart or not */
+        l.sw    PT_SYSCALLNO(r1),r11
 
 _syscall_check_trace_enter:
         /* If TIF_SYSCALL_TRACE is set, then we want to do syscall tracing */
@@ -731,7 +731,7 @@ _syscall_trace_enter:
          * so that we can do the syscall for real and return to the syscall
          * hot path.
          */
-        l.lwz   r11,PT_GPR11(r1)
+        l.lwz   r11,PT_SYSCALLNO(r1)
         l.lwz   r3,PT_GPR3(r1)
         l.lwz   r4,PT_GPR4(r1)
         l.lwz   r5,PT_GPR5(r1)
@@ -894,16 +894,6 @@ ENTRY(ret_from_fork)
         l.jal   schedule_tail
          l.nop
 
-        /* Check if we are a kernel thread */
-        l.sfeqi r20,0
-        l.bf    1f
-         l.nop
-
-        /* ...we are a kernel thread so invoke the requested callback */
-        l.jalr  r20
-         l.or   r3,r22,r0
-
-1:
         /* _syscall_returns expect r11 to contain return value */
         l.lwz   r11,PT_GPR11(r1)
 
@@ -925,6 +915,26 @@ ENTRY(ret_from_fork)
         l.j     _syscall_return
          l.nop
 
+/* Since syscalls don't save call-clobbered registers, the args to
+ * kernel_thread_helper will need to be passed through callee-saved
+ * registers and copied to the parameter registers when the thread
+ * begins running.
+ *
+ * See arch/openrisc/kernel/process.c:
+ * The args are passed as follows:
+ *   arg1 (r3) : passed in r20
+ *   arg2 (r4) : passed in r22
+ */
+
+ENTRY(_kernel_thread_helper)
+        l.or    r3,r20,r0
+        l.or    r4,r22,r0
+        l.movhi r31,hi(kernel_thread_helper)
+        l.ori   r31,r31,lo(kernel_thread_helper)
+        l.jr    r31
+         l.nop
+
+
 /* ========================================================[ switch ] === */
 
 /*
@@ -1034,13 +1044,8 @@ ENTRY(_switch)
         /* Unwind stack to pre-switch state */
         l.addi  r1,r1,(INT_FRAME_SIZE)
 
-        /* Return via the link-register back to where we 'came from', where
-         * that may be either schedule(), ret_from_fork(), or
-         * ret_from_kernel_thread().  If we are returning to a new thread,
-         * we are expected to have set up the arg to schedule_tail already,
-         * hence we do so here unconditionally:
-         */
-        l.lwz   r3,TI_STACK(r3)         /* Load 'prev' as schedule_tail arg */
+        /* Return via the link-register back to where we 'came from', where that can be
+         * either schedule() or return_from_fork()... */
         l.jr    r9
          l.nop
 
@@ -1071,18 +1076,22 @@ _fork_save_extra_regs_and_call:
         l.jr    r29
          l.sw    PT_GPR28(r1),r28
 
-ENTRY(__sys_clone)
-        l.movhi r29,hi(sys_clone)
-        l.ori   r29,r29,lo(sys_clone)
+ENTRY(sys_clone)
+        l.movhi r29,hi(_sys_clone)
+        l.ori   r29,r29,lo(_sys_clone)
         l.j     _fork_save_extra_regs_and_call
          l.addi r7,r1,0
 
-ENTRY(__sys_fork)
-        l.movhi r29,hi(sys_fork)
-        l.ori   r29,r29,lo(sys_fork)
+ENTRY(sys_fork)
+        l.movhi r29,hi(_sys_fork)
+        l.ori   r29,r29,lo(_sys_fork)
         l.j     _fork_save_extra_regs_and_call
          l.addi r3,r1,0
 
+ENTRY(sys_execve)
+        l.j     _sys_execve
+         l.addi r6,r1,0
+
 ENTRY(sys_sigaltstack)
         l.j     _sys_sigaltstack
          l.addi r5,r1,0
@@ -1108,10 +1117,10 @@ ENTRY(sys_rt_sigreturn)
 ENTRY(sys_or1k_atomic)
         /* FIXME: This ignores r3 and always does an XCHG */
         DISABLE_INTERRUPTS(r17,r19)
-        l.lwz   r29,0(r4)
-        l.lwz   r27,0(r5)
-        l.sw    0(r4),r27
-        l.sw    0(r5),r29
+        l.lwz   r30,0(r4)
+        l.lwz   r28,0(r5)
+        l.sw    0(r4),r28
+        l.sw    0(r5),r30
         ENABLE_INTERRUPTS(r17)
         l.jr    r9
          l.or   r11,r0,r0