sparc64: Adjust KTSB assembler to support larger physical addresses.

As currently coded the KTSB accesses in the kernel only support up to
47 bits of physical addressing.

Adjust the instruction and patching sequence in order to support
arbitrary 64 bits addresses.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>

2 files changed, 37 insertions, 21 deletions

diff --git a/arch/sparc/include/asm/tsb.h b/arch/sparc/include/asm/tsb.h
index 2e268b646348..a2f541905715 100644
--- a/arch/sparc/include/asm/tsb.h
+++ b/arch/sparc/include/asm/tsb.h
@@ -256,8 +256,6 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
         (KERNEL_TSB_SIZE_BYTES / 16)
 #define KERNEL_TSB4M_NENTRIES   4096
 
-#define KTSB_PHYS_SHIFT         15
-
         /* Do a kernel TSB lookup at tl>0 on VADDR+TAG, branch to OK_LABEL
          * on TSB hit.  REG1, REG2, REG3, and REG4 are used as temporaries
          * and the found TTE will be left in REG1.  REG3 and REG4 must
@@ -266,17 +264,15 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
          * VADDR and TAG will be preserved and not clobbered by this macro.
          */
 #define KERN_TSB_LOOKUP_TL1(VADDR, TAG, REG1, REG2, REG3, REG4, OK_LABEL) \
-661:    sethi           %hi(swapper_tsb), REG1;                 \
-        or              REG1, %lo(swapper_tsb), REG1; \
+661:    sethi           %uhi(swapper_tsb), REG1; \
+        sethi           %hi(swapper_tsb), REG2; \
+        or              REG1, %ulo(swapper_tsb), REG1; \
+        or              REG2, %lo(swapper_tsb), REG2; \
         .section        .swapper_tsb_phys_patch, "ax"; \
         .word           661b; \
         .previous; \
-661:    nop; \
-        .section        .tsb_ldquad_phys_patch, "ax"; \
-        .word           661b; \
-        sllx            REG1, KTSB_PHYS_SHIFT, REG1; \
-        sllx            REG1, KTSB_PHYS_SHIFT, REG1; \
-        .previous; \
+        sllx            REG1, 32, REG1; \
+        or              REG1, REG2, REG1; \
         srlx            VADDR, PAGE_SHIFT, REG2; \
         and             REG2, (KERNEL_TSB_NENTRIES - 1), REG2; \
         sllx            REG2, 4, REG2; \
@@ -291,17 +287,15 @@ extern struct tsb_phys_patch_entry __tsb_phys_patch, __tsb_phys_patch_end;
          * we can make use of that for the index computation.
          */
 #define KERN_TSB4M_LOOKUP_TL1(TAG, REG1, REG2, REG3, REG4, OK_LABEL) \
-661:    sethi           %hi(swapper_4m_tsb), REG1;           \
-        or              REG1, %lo(swapper_4m_tsb), REG1; \
+661:    sethi           %uhi(swapper_4m_tsb), REG1; \
+        sethi           %hi(swapper_4m_tsb), REG2; \
+        or              REG1, %ulo(swapper_4m_tsb), REG1; \
+        or              REG2, %lo(swapper_4m_tsb), REG2; \
         .section        .swapper_4m_tsb_phys_patch, "ax"; \
         .word           661b; \
         .previous; \
-661:    nop; \
-        .section        .tsb_ldquad_phys_patch, "ax"; \
-        .word           661b; \
-        sllx            REG1, KTSB_PHYS_SHIFT, REG1; \
-        sllx            REG1, KTSB_PHYS_SHIFT, REG1; \
-        .previous; \
+        sllx            REG1, 32, REG1; \
+        or              REG1, REG2, REG1; \
         and             TAG, (KERNEL_TSB4M_NENTRIES - 1), REG2; \
         sllx            REG2, 4, REG2; \
         add             REG1, REG2, REG2; \
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index c241c5723373..35fcc9cb960d 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1733,19 +1733,41 @@ static void __init tsb_phys_patch(void)
 static struct hv_tsb_descr ktsb_descr[NUM_KTSB_DESCR];
 extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];
 
+/* The swapper TSBs are loaded with a base sequence of:
+ *
+ *      sethi   %uhi(SYMBOL), REG1
+ *      sethi   %hi(SYMBOL), REG2
+ *      or      REG1, %ulo(SYMBOL), REG1
+ *      or      REG2, %lo(SYMBOL), REG2
+ *      sllx    REG1, 32, REG1
+ *      or      REG1, REG2, REG1
+ *
+ * When we use physical addressing for the TSB accesses, we patch the
+ * first four instructions in the above sequence.
+ */
+
 static void patch_one_ktsb_phys(unsigned int *start, unsigned int *end, unsigned long pa)
 {
-        pa >>= KTSB_PHYS_SHIFT;
+        unsigned long high_bits, low_bits;
+
+        high_bits = (pa >> 32) & 0xffffffff;
+        low_bits = (pa >> 0) & 0xffffffff;
 
         while (start < end) {
                 unsigned int *ia = (unsigned int *)(unsigned long)*start;
 
-                ia[0] = (ia[0] & ~0x3fffff) | (pa >> 10);
+                ia[0] = (ia[0] & ~0x3fffff) | (high_bits >> 10);
                 __asm__ __volatile__("flush     %0" : : "r" (ia));
 
-                ia[1] = (ia[1] & ~0x3ff) | (pa & 0x3ff);
+                ia[1] = (ia[1] & ~0x3fffff) | (low_bits >> 10);
                 __asm__ __volatile__("flush     %0" : : "r" (ia + 1));
 
+                ia[2] = (ia[2] & ~0x1fff) | (high_bits & 0x3ff);
+                __asm__ __volatile__("flush     %0" : : "r" (ia + 2));
+
+                ia[3] = (ia[3] & ~0x1fff) | (low_bits & 0x3ff);
+                __asm__ __volatile__("flush     %0" : : "r" (ia + 3));
+
                 start++;
         }
 }