arch/tile: parameterize system PLs to support KVM port

While not a port to KVM (yet), this change modifies the kernel
to be able to build either at PL1 or at PL2 with a suitable
config switch.  Pushing up this change avoids handling branch
merge issues going forward with the KVM work.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

1 files changed, 36 insertions, 31 deletions

diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S
index f87c5c044d6b..206dc7e1fe36 100644
--- a/arch/tile/kernel/intvec_32.S
+++ b/arch/tile/kernel/intvec_32.S
@@ -32,8 +32,8 @@
 # error "No support for kernel preemption currently"
 #endif
 
-#if INT_INTCTRL_1 < 32 || INT_INTCTRL_1 >= 48
-# error INT_INTCTRL_1 coded to set high interrupt mask
+#if INT_INTCTRL_K < 32 || INT_INTCTRL_K >= 48
+# error INT_INTCTRL_K coded to set high interrupt mask
 #endif
 
 #define PTREGS_PTR(reg, ptreg) addli reg, sp, C_ABI_SAVE_AREA_SIZE + (ptreg)
@@ -132,8 +132,8 @@ intvec_\vecname:
 
         /* Temporarily save a register so we have somewhere to work. */
 
-        mtspr   SYSTEM_SAVE_1_1, r0
-        mfspr   r0, EX_CONTEXT_1_1
+        mtspr   SPR_SYSTEM_SAVE_K_1, r0
+        mfspr   r0, SPR_EX_CONTEXT_K_1
 
         /* The cmpxchg code clears sp to force us to reset it here on fault. */
         {
@@ -167,18 +167,18 @@ intvec_\vecname:
          * The page_fault handler may be downcalled directly by the
          * hypervisor even when Linux is running and has ICS set.
          *
-         * In this case the contents of EX_CONTEXT_1_1 reflect the
+         * In this case the contents of EX_CONTEXT_K_1 reflect the
          * previous fault and can't be relied on to choose whether or
          * not to reinitialize the stack pointer.  So we add a test
-         * to see whether SYSTEM_SAVE_1_2 has the high bit set,
+         * to see whether SYSTEM_SAVE_K_2 has the high bit set,
          * and if so we don't reinitialize sp, since we must be coming
          * from Linux.  (In fact the precise case is !(val & ~1),
          * but any Linux PC has to have the high bit set.)
          *
-         * Note that the hypervisor *always* sets SYSTEM_SAVE_1_2 for
+         * Note that the hypervisor *always* sets SYSTEM_SAVE_K_2 for
          * any path that turns into a downcall to one of our TLB handlers.
          */
-        mfspr   r0, SYSTEM_SAVE_1_2
+        mfspr   r0, SPR_SYSTEM_SAVE_K_2
         {
          blz    r0, 0f    /* high bit in S_S_1_2 is for a PC to use */
          move   r0, sp
@@ -187,12 +187,12 @@ intvec_\vecname:
 
 2:
         /*
-         * SYSTEM_SAVE_1_0 holds the cpu number in the low bits, and
+         * SYSTEM_SAVE_K_0 holds the cpu number in the low bits, and
          * the current stack top in the higher bits.  So we recover
          * our stack top by just masking off the low bits, then
          * point sp at the top aligned address on the actual stack page.
          */
-        mfspr   r0, SYSTEM_SAVE_1_0
+        mfspr   r0, SPR_SYSTEM_SAVE_K_0
         mm      r0, r0, zero, LOG2_THREAD_SIZE, 31
 
 0:
@@ -254,7 +254,7 @@ intvec_\vecname:
          sw     sp, r3
          addli  sp, sp, PTREGS_OFFSET_PC - PTREGS_OFFSET_REG(3)
         }
-        mfspr   r0, EX_CONTEXT_1_0
+        mfspr   r0, SPR_EX_CONTEXT_K_0
         .ifc \processing,handle_syscall
         /*
          * Bump the saved PC by one bundle so that when we return, we won't
@@ -267,7 +267,7 @@ intvec_\vecname:
          sw     sp, r0
          addli  sp, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
         }
-        mfspr   r0, EX_CONTEXT_1_1
+        mfspr   r0, SPR_EX_CONTEXT_K_1
         {
          sw     sp, r0
          addi   sp, sp, PTREGS_OFFSET_FAULTNUM - PTREGS_OFFSET_EX1
@@ -289,7 +289,7 @@ intvec_\vecname:
          .endif
          addli  sp, sp, PTREGS_OFFSET_REG(0) - PTREGS_OFFSET_FAULTNUM
         }
-        mfspr   r0, SYSTEM_SAVE_1_1    /* Original r0 */
+        mfspr   r0, SPR_SYSTEM_SAVE_K_1    /* Original r0 */
         {
          sw     sp, r0
          addi   sp, sp, -PTREGS_OFFSET_REG(0) - 4
@@ -309,12 +309,12 @@ intvec_\vecname:
          * See discussion below at "finish_interrupt_save".
          */
         .ifc \c_routine, do_page_fault
-        mfspr   r2, SYSTEM_SAVE_1_3   /* address of page fault */
-        mfspr   r3, SYSTEM_SAVE_1_2   /* info about page fault */
+        mfspr   r2, SPR_SYSTEM_SAVE_K_3   /* address of page fault */
+        mfspr   r3, SPR_SYSTEM_SAVE_K_2   /* info about page fault */
         .else
         .ifc \vecnum, INT_DOUBLE_FAULT
         {
-         mfspr  r2, SYSTEM_SAVE_1_2   /* double fault info from HV */
+         mfspr  r2, SPR_SYSTEM_SAVE_K_2   /* double fault info from HV */
          movei  r3, 0
         }
         .else
@@ -467,7 +467,7 @@ intvec_\vecname:
         /* Load tp with our per-cpu offset. */
 #ifdef CONFIG_SMP
         {
-         mfspr  r20, SYSTEM_SAVE_1_0
+         mfspr  r20, SPR_SYSTEM_SAVE_K_0
          moveli r21, lo16(__per_cpu_offset)
         }
         {
@@ -487,7 +487,7 @@ intvec_\vecname:
          * We load flags in r32 here so we can jump to .Lrestore_regs
          * directly after do_page_fault_ics() if necessary.
          */
-        mfspr   r32, EX_CONTEXT_1_1
+        mfspr   r32, SPR_EX_CONTEXT_K_1
         {
          andi   r32, r32, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
          PTREGS_PTR(r21, PTREGS_OFFSET_FLAGS)
@@ -957,11 +957,11 @@ STD_ENTRY(interrupt_return)
         pop_reg_zero r21, r3, sp, PTREGS_OFFSET_EX1 - PTREGS_OFFSET_PC
         pop_reg_zero lr, r4, sp, PTREGS_OFFSET_REG(52) - PTREGS_OFFSET_EX1
         {
-         mtspr  EX_CONTEXT_1_0, r21
+         mtspr  SPR_EX_CONTEXT_K_0, r21
          move   r5, zero
         }
         {
-         mtspr  EX_CONTEXT_1_1, lr
+         mtspr  SPR_EX_CONTEXT_K_1, lr
          andi   lr, lr, SPR_EX_CONTEXT_1_1__PL_MASK  /* mask off ICS */
         }
 
@@ -1199,7 +1199,7 @@ STD_ENTRY(interrupt_return)
         STD_ENDPROC(interrupt_return)
 
         /*
-         * This interrupt variant clears the INT_INTCTRL_1 interrupt mask bit
+         * This interrupt variant clears the INT_INTCTRL_K interrupt mask bit
          * before returning, so we can properly get more downcalls.
          */
         .pushsection .text.handle_interrupt_downcall,"ax"
@@ -1208,11 +1208,11 @@ handle_interrupt_downcall:
         check_single_stepping normal, .Ldispatch_downcall
 .Ldispatch_downcall:
 
-        /* Clear INTCTRL_1 from the set of interrupts we ever enable. */
+        /* Clear INTCTRL_K from the set of interrupts we ever enable. */
         GET_INTERRUPTS_ENABLED_MASK_PTR(r30)
         {
          addi   r30, r30, 4
-         movei  r31, INT_MASK(INT_INTCTRL_1)
+         movei  r31, INT_MASK(INT_INTCTRL_K)
         }
         {
          lw     r20, r30
@@ -1227,7 +1227,7 @@ handle_interrupt_downcall:
         }
         FEEDBACK_REENTER(handle_interrupt_downcall)
 
-        /* Allow INTCTRL_1 to be enabled next time we enable interrupts. */
+        /* Allow INTCTRL_K to be enabled next time we enable interrupts. */
         lw      r20, r30
         or      r20, r20, r31
         sw      r30, r20
@@ -1509,7 +1509,7 @@ handle_ill:
 /* Various stub interrupt handlers and syscall handlers */
 
 STD_ENTRY_LOCAL(_kernel_double_fault)
-        mfspr   r1, EX_CONTEXT_1_0
+        mfspr   r1, SPR_EX_CONTEXT_K_0
         move    r2, lr
         move    r3, sp
         move    r4, r52
@@ -1518,7 +1518,7 @@ STD_ENTRY_LOCAL(_kernel_double_fault)
         STD_ENDPROC(_kernel_double_fault)
 
 STD_ENTRY_LOCAL(bad_intr)
-        mfspr   r2, EX_CONTEXT_1_0
+        mfspr   r2, SPR_EX_CONTEXT_K_0
         panic   "Unhandled interrupt %#x: PC %#lx"
         STD_ENDPROC(bad_intr)
 
@@ -1560,7 +1560,7 @@ STD_ENTRY(_sys_clone)
  * a page fault which would assume the stack was valid, it does
  * save/restore the stack pointer and zero it out to make sure it gets reset.
  * Since we always keep interrupts disabled, the hypervisor won't
- * clobber our EX_CONTEXT_1_x registers, so we don't save/restore them
+ * clobber our EX_CONTEXT_K_x registers, so we don't save/restore them
  * (other than to advance the PC on return).
  *
  * We have to manually validate the user vs kernel address range
@@ -1766,7 +1766,7 @@ ENTRY(sys_cmpxchg)
         /* Do slow mtspr here so the following "mf" waits less. */
         {
          move   sp, r27
-         mtspr  EX_CONTEXT_1_0, r28
+         mtspr  SPR_EX_CONTEXT_K_0, r28
         }
         mf
 
@@ -1785,7 +1785,7 @@ ENTRY(sys_cmpxchg)
         }
         {
          move   sp, r27
-         mtspr  EX_CONTEXT_1_0, r28
+         mtspr  SPR_EX_CONTEXT_K_0, r28
         }
         iret
 
@@ -1813,7 +1813,7 @@ ENTRY(sys_cmpxchg)
 #endif
 
         /* Issue the slow SPR here while the tns result is in flight. */
-        mfspr   r28, EX_CONTEXT_1_0
+        mfspr   r28, SPR_EX_CONTEXT_K_0
 
         {
          addi   r28, r28, 8    /* return to the instruction after the swint1 */
@@ -1901,7 +1901,7 @@ ENTRY(sys_cmpxchg)
 .Lcmpxchg64_mismatch:
         {
          move   sp, r27
-         mtspr  EX_CONTEXT_1_0, r28
+         mtspr  SPR_EX_CONTEXT_K_0, r28
         }
         mf
         {
@@ -1982,8 +1982,13 @@ int_unalign:
         int_hand     INT_PERF_COUNT, PERF_COUNT, \
                      op_handle_perf_interrupt, handle_nmi
         int_hand     INT_INTCTRL_3, INTCTRL_3, bad_intr
+#if CONFIG_KERNEL_PL == 2
+        dc_dispatch  INT_INTCTRL_2, INTCTRL_2
+        int_hand     INT_INTCTRL_1, INTCTRL_1, bad_intr
+#else
         int_hand     INT_INTCTRL_2, INTCTRL_2, bad_intr
         dc_dispatch  INT_INTCTRL_1, INTCTRL_1
+#endif
         int_hand     INT_INTCTRL_0, INTCTRL_0, bad_intr
         int_hand     INT_MESSAGE_RCV_DWNCL, MESSAGE_RCV_DWNCL, \
                      hv_message_intr, handle_interrupt_downcall