[SPARC64]: Implement sun4v TSB miss handlers.

When we register a TSB with the hypervisor, so that it or hardware can
handle TLB misses and do the TSB walk for us, the hypervisor traps
down to these trap when it incurs a TSB miss.

Processing is simple, we load the missing virtual address and context,
and do a full page table walk.

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 84 insertions, 9 deletions

diff --git a/arch/sparc64/kernel/sun4v_tlb_miss.S b/arch/sparc64/kernel/sun4v_tlb_miss.S
index 58ea5dd8573c..b8678b5557aa 100644
--- a/arch/sparc64/kernel/sun4v_tlb_miss.S
+++ b/arch/sparc64/kernel/sun4v_tlb_miss.S
@@ -187,6 +187,57 @@ sun4v_dtlb_prot:
         ba,pt           %xcc, sparc64_realfault_common
          mov            FAULT_CODE_DTLB | FAULT_CODE_WRITE, %g4
 
+        /* Called from trap table with &trap_block[smp_processor_id()] in
+         * %g5 and SCRATCHPAD_UTSBREG1 contents in %g1.
+         */
+sun4v_itsb_miss:
+        ldx     [%g5 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_I_ADDR_OFFSET], %g4
+        ldx     [%g5 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_I_CTX_OFFSET], %g5
+
+        srlx    %g4, 22, %g7
+        sllx    %g5, 48, %g6
+        or      %g6, %g7, %g6
+        brz,pn  %g5, kvmap_itlb_4v
+         nop
+
+        ba,pt   %xcc, sun4v_tsb_miss_common
+         mov    FAULT_CODE_ITLB, %g3
+
+        /* Called from trap table with &trap_block[smp_processor_id()] in
+         * %g5 and SCRATCHPAD_UTSBREG1 contents in %g1.
+         */
+sun4v_dtsb_miss:
+        ldx     [%g5 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_D_ADDR_OFFSET], %g4
+        ldx     [%g5 + TRAP_PER_CPU_FAULT_INFO + HV_FAULT_D_CTX_OFFSET], %g5
+
+        srlx    %g4, 22, %g7
+        sllx    %g5, 48, %g6
+        or      %g6, %g7, %g6
+        brz,pn  %g5, kvmap_dtlb_4v
+         nop
+
+        mov     FAULT_CODE_DTLB, %g3
+
+        /* Create TSB pointer into %g1.  This is something like:
+         *
+         * index_mask = (512 << (tsb_reg & 0x7UL)) - 1UL;
+         * tsb_base = tsb_reg & ~0x7UL;
+         * tsb_index = ((vaddr >> PAGE_SHIFT) & tsb_mask);
+         * tsb_ptr = tsb_base + (tsb_index * 16);
+         */
+sun4v_tsb_miss_common:
+        and     %g1, 0x7, %g2
+        andn    %g1, 0x7, %g1
+        mov     512, %g7
+        sllx    %g7, %g2, %g7
+        sub     %g7, 1, %g7
+        srlx    %g4, PAGE_SHIFT, %g2
+        and     %g2, %g7, %g2
+        sllx    %g2, 4, %g2
+        ba,pt   %xcc, tsb_miss_page_table_walk
+         add    %g1, %g2, %g1
+
+
 #define BRANCH_ALWAYS   0x10680000
 #define NOP             0x01000000
 #define SUN4V_DO_PATCH(OLD, NEW)        \
diff --git a/arch/sparc64/kernel/tsb.S b/arch/sparc64/kernel/tsb.S
index 819a6ef9799f..c848c8847cdc 100644
--- a/arch/sparc64/kernel/tsb.S
+++ b/arch/sparc64/kernel/tsb.S
@@ -35,8 +35,11 @@ tsb_miss_itlb:
          nop
 
         /* The sun4v TLB miss handlers jump directly here instead
-         * of tsb_miss_{d,i}tlb with the missing virtual address
-         * already loaded into %g4.
+         * of tsb_miss_{d,i}tlb with registers setup as follows:
+         *
+         * %g4: missing virtual address
+         * %g1: TSB entry address loaded
+         * %g6: TAG TARGET ((vaddr >> 22) | (ctx << 48))
          */
 tsb_miss_page_table_walk:
         TRAP_LOAD_PGD_PHYS(%g7, %g5)
diff --git a/arch/sparc64/kernel/ttable.S b/arch/sparc64/kernel/ttable.S
index 1608ba4bf1c1..a9d210e11eb3 100644
--- a/arch/sparc64/kernel/ttable.S
+++ b/arch/sparc64/kernel/ttable.S
@@ -1,7 +1,6 @@
-/* $Id: ttable.S,v 1.38 2002/02/09 19:49:30 davem Exp $
- * ttable.S: Sparc V9 Trap Table(s) with SpitFire/Cheetah extensions.
+/* ttable.S: Sparc V9 Trap Table(s) with SpitFire/Cheetah/SUN4V extensions.
  *
- * Copyright (C) 1996, 2001 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996, 2001, 2006 David S. Miller (davem@davemloft.net)
  */
 
 #include <linux/config.h>
@@ -22,7 +21,8 @@ tl0_iax:	membar #Sync
 tl0_resv009:    BTRAP(0x9)
 tl0_iae:        membar #Sync
                 TRAP_NOSAVE_7INSNS(__spitfire_access_error)
-tl0_resv00b:    BTRAP(0xb) BTRAP(0xc) BTRAP(0xd) BTRAP(0xe) BTRAP(0xf)
+tl0_itsb_4v:    SUN4V_ITSB_MISS
+tl0_resv00c:    BTRAP(0xc) BTRAP(0xd) BTRAP(0xe) BTRAP(0xf)
 tl0_ill:        membar #Sync
                 TRAP_7INSNS(do_illegal_instruction)
 tl0_privop:     TRAP(do_privop)
@@ -38,7 +38,7 @@ tl0_div0:	TRAP(do_div0)
 tl0_resv029:    BTRAP(0x29) BTRAP(0x2a) BTRAP(0x2b) BTRAP(0x2c) BTRAP(0x2d) BTRAP(0x2e)
 tl0_resv02f:    BTRAP(0x2f)
 tl0_dax:        TRAP_NOSAVE(__spitfire_data_access_exception)
-tl0_resv031:    BTRAP(0x31)
+tl0_dtsb_4v:    SUN4V_DTSB_MISS
 tl0_dae:        membar #Sync
                 TRAP_NOSAVE_7INSNS(__spitfire_access_error)
 tl0_resv033:    BTRAP(0x33)
@@ -185,7 +185,8 @@ tl1_iax:	TRAP_NOSAVE(__spitfire_insn_access_exception_tl1)
 tl1_resv009:    BTRAPTL1(0x9)
 tl1_iae:        membar #Sync
                 TRAP_NOSAVE_7INSNS(__spitfire_access_error)
-tl1_resv00b:    BTRAPTL1(0xb) BTRAPTL1(0xc) BTRAPTL1(0xd) BTRAPTL1(0xe) BTRAPTL1(0xf)
+tl1_itsb_4v:    SUN4V_ITSB_MISS
+tl1_resv00c:    BTRAPTL1(0xc) BTRAPTL1(0xd) BTRAPTL1(0xe) BTRAPTL1(0xf)
 tl1_ill:        TRAPTL1(do_ill_tl1)
 tl1_privop:     BTRAPTL1(0x11)
 tl1_resv012:    BTRAPTL1(0x12) BTRAPTL1(0x13) BTRAPTL1(0x14) BTRAPTL1(0x15)
@@ -201,7 +202,7 @@ tl1_div0:	TRAPTL1(do_div0_tl1)
 tl1_resv029:    BTRAPTL1(0x29) BTRAPTL1(0x2a) BTRAPTL1(0x2b) BTRAPTL1(0x2c)
 tl1_resv02d:    BTRAPTL1(0x2d) BTRAPTL1(0x2e) BTRAPTL1(0x2f)
 tl1_dax:        TRAP_NOSAVE(__spitfire_data_access_exception_tl1)
-tl1_resv031:    BTRAPTL1(0x31)
+tl1_dtsb_4v:    SUN4V_DTSB_MISS
 tl1_dae:        membar #Sync
                 TRAP_NOSAVE_7INSNS(__spitfire_access_error)
 tl1_resv033:    BTRAPTL1(0x33)
diff --git a/include/asm-sparc64/ttable.h b/include/asm-sparc64/ttable.h
index f912f52c0c7f..972f913709a3 100644
--- a/include/asm-sparc64/ttable.h
+++ b/include/asm-sparc64/ttable.h
@@ -180,6 +180,26 @@
 #define KPROBES_TRAP(lvl) TRAP_ARG(bad_trap, lvl)
 #endif
 
+#define SUN4V_ITSB_MISS                         \
+        mov     SCRATCHPAD_CPUID, %g1;          \
+        ldxa    [%g1] ASI_SCRATCHPAD, %g2;      \
+        ldxa    [%g1 + %g1] ASI_SCRATCHPAD, %g1;\
+        sethi   %hi(trap_block), %g5;           \
+        sllx    %g2, TRAP_BLOCK_SZ_SHIFT, %g2;  \
+        or      %g5, %lo(trap_block), %g5;      \
+        ba,pt   %xcc, sun4v_itsb_miss;          \
+         add    %g5, %g2, %g5;
+
+#define SUN4V_DTSB_MISS                         \
+        mov     SCRATCHPAD_CPUID, %g1;          \
+        ldxa    [%g1] ASI_SCRATCHPAD, %g2;      \
+        ldxa    [%g1 + %g1] ASI_SCRATCHPAD, %g1;\
+        sethi   %hi(trap_block), %g5;           \
+        sllx    %g2, TRAP_BLOCK_SZ_SHIFT, %g2;  \
+        or      %g5, %lo(trap_block), %g5;      \
+        ba,pt   %xcc, sun4v_dtsb_miss;          \
+         add    %g5, %g2, %g5;
+
 /* Before touching these macros, you owe it to yourself to go and
  * see how arch/sparc64/kernel/winfixup.S works... -DaveM
  *