[SPARC64]: Break up inherit_prom_mappings() into it's constituent parts.

This thing was just a huge monolithic mess, so chop it up.

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

1 files changed, 160 insertions, 141 deletions

diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index 141d4cc5fc53..11d2187990d4 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -362,84 +362,107 @@ unsigned long prom_virt_to_phys(unsigned long promva, int *error)
         return(base + (promva & (BASE_PAGE_SIZE - 1)));
 }
 
-static void inherit_prom_mappings(void)
+static inline int in_obp_range(unsigned long vaddr)
 {
-        unsigned long phys_page, tte_vaddr, tte_data;
-        void (*remap_func)(unsigned long, unsigned long, int);
-        pmd_t *pmdp;
-        pte_t *ptep;
-        int node, n, i, tsz;
+        return (vaddr >= LOW_OBP_ADDRESS &&
+                vaddr < HI_OBP_ADDRESS);
+}
 
-        node = prom_finddevice("/virtual-memory");
-        n = prom_getproplen(node, "translations");
-        if (n == 0 || n == -1) {
-                prom_printf("prom_mappings: Couldn't get size.\n");
-                prom_halt();
-        }
-        n += 24 * sizeof(struct linux_prom_translation);
-        if (n > sizeof(prom_trans)) {
-                prom_printf("prom_mappings: prom_trans too small, "
-                            "need %Zd bytes\n", n);
-                prom_halt();
-        }
-        tsz = n;
-        if ((n = prom_getproperty(node, "translations",
-                                  (char *)&prom_trans[0], tsz)) == -1) {
-                prom_printf("prom_mappings: Couldn't get property.\n");
-                prom_halt();
+/* The obp translations are saved based on 8k pagesize, since obp can
+ * use a mixture of pagesizes. Misses to the LOW_OBP_ADDRESS ->
+ * HI_OBP_ADDRESS range are handled in entry.S and do not use the vpte
+ * scheme (also, see rant in inherit_locked_prom_mappings()).
+ */
+static void build_obp_range(unsigned long start, unsigned long end, unsigned long data)
+{
+        unsigned long vaddr;
+
+        for (vaddr = start; vaddr < end; vaddr += BASE_PAGE_SIZE) {
+                unsigned long val;
+                pmd_t *pmdp;
+                pte_t *ptep;
+
+                pmdp = prompmd + ((vaddr >> 23) & 0x7ff);
+                if (pmd_none(*pmdp)) {
+                        ptep = __alloc_bootmem(BASE_PAGE_SIZE,
+                                               BASE_PAGE_SIZE,
+                                               bootmap_base);
+                        if (ptep == NULL)
+                                early_pgtable_allocfail("pte");
+                        memset(ptep, 0, BASE_PAGE_SIZE);
+                        pmd_set(pmdp, ptep);
+                }
+                ptep = (pte_t *)__pmd_page(*pmdp) +
+                        ((vaddr >> 13) & 0x3ff);
+
+                val = data;
+
+                /* Clear diag TTE bits. */
+                if (tlb_type == spitfire)
+                        val &= ~0x0003fe0000000000UL;
+
+                set_pte_at(&init_mm, vaddr,
+                           ptep, __pte(val | _PAGE_MODIFIED));
+                data += BASE_PAGE_SIZE;
         }
-        n = n / sizeof(struct linux_prom_translation);
+}
 
-        /* The obp translations are saved based on 8k pagesize, since obp
-         * can use a mixture of pagesizes. Misses to the 0xf0000000 ->
-         * 0x100000000, ie obp range, are handled in entry.S and do not
-         * use the vpte scheme (see rant: inherit_locked_prom_mappings).
-         */
 #define OBP_PMD_SIZE 2048
-        prompmd = __alloc_bootmem(OBP_PMD_SIZE, OBP_PMD_SIZE, bootmap_base);
+static void build_obp_pgtable(int prom_trans_ents)
+{
+        int i;
+
+        prompmd = __alloc_bootmem(OBP_PMD_SIZE, OBP_PMD_SIZE,
+                                  bootmap_base);
         if (prompmd == NULL)
                 early_pgtable_allocfail("pmd");
         memset(prompmd, 0, OBP_PMD_SIZE);
-        for (i = 0; i < n; i++) {
-                unsigned long vaddr;
-
-                if (prom_trans[i].virt >= LOW_OBP_ADDRESS && prom_trans[i].virt < HI_OBP_ADDRESS) {
-                        for (vaddr = prom_trans[i].virt;
-                             ((vaddr < prom_trans[i].virt + prom_trans[i].size) && 
-                             (vaddr < HI_OBP_ADDRESS));
-                             vaddr += BASE_PAGE_SIZE) {
-                                unsigned long val;
-
-                                pmdp = prompmd + ((vaddr >> 23) & 0x7ff);
-                                if (pmd_none(*pmdp)) {
-                                        ptep = __alloc_bootmem(BASE_PAGE_SIZE,
-                                                               BASE_PAGE_SIZE,
-                                                               bootmap_base);
-                                        if (ptep == NULL)
-                                                early_pgtable_allocfail("pte");
-                                        memset(ptep, 0, BASE_PAGE_SIZE);
-                                        pmd_set(pmdp, ptep);
-                                }
-                                ptep = (pte_t *)__pmd_page(*pmdp) +
-                                                ((vaddr >> 13) & 0x3ff);
+        for (i = 0; i < prom_trans_ents; i++) {
+                unsigned long start, end;
 
-                                val = prom_trans[i].data;
+                if (!in_obp_range(prom_trans[i].virt))
+                        continue;
 
-                                /* Clear diag TTE bits. */
-                                if (tlb_type == spitfire)
-                                        val &= ~0x0003fe0000000000UL;
+                start = prom_trans[i].virt;
+                end = start + prom_trans[i].size;
+                if (end > HI_OBP_ADDRESS)
+                        end = HI_OBP_ADDRESS;
 
-                                set_pte_at(&init_mm, vaddr,
-                                           ptep, __pte(val | _PAGE_MODIFIED));
-                                prom_trans[i].data += BASE_PAGE_SIZE;
-                        }
-                }
+                build_obp_range(start, end, prom_trans[i].data);
         }
         prom_pmd_phys = __pa(prompmd);
+}
 
-        /* Now fixup OBP's idea about where we really are mapped. */
-        prom_printf("Remapping the kernel... ");
+/* Read OBP translations property into 'prom_trans[]'.
+ * Return the number of entries.
+ */
+static int read_obp_translations(void)
+{
+        int n, node;
 
+        node = prom_finddevice("/virtual-memory");
+        n = prom_getproplen(node, "translations");
+        if (unlikely(n == 0 || n == -1)) {
+                prom_printf("prom_mappings: Couldn't get size.\n");
+                prom_halt();
+        }
+        if (unlikely(n > sizeof(prom_trans))) {
+                prom_printf("prom_mappings: Size %Zd is too big.\n", n);
+                prom_halt();
+        }
+
+        if ((n = prom_getproperty(node, "translations",
+                                  (char *)&prom_trans[0],
+                                  sizeof(prom_trans))) == -1) {
+                prom_printf("prom_mappings: Couldn't get property.\n");
+                prom_halt();
+        }
+        n = n / sizeof(struct linux_prom_translation);
+        return n;
+}
+
+static inline void early_spitfire_errata32(void)
+{
         /* Spitfire Errata #32 workaround */
         /* NOTE: Using plain zero for the context value is
          *       correct here, we are not using the Linux trap
@@ -449,23 +472,13 @@ static void inherit_prom_mappings(void)
         __asm__ __volatile__("stxa      %0, [%1] %2\n\t"
                              "flush     %%g6"
                              : /* No outputs */
-                             : "r" (0), "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));
-
-        switch (tlb_type) {
-        default:
-        case spitfire:
-                phys_page = spitfire_get_dtlb_data(sparc64_highest_locked_tlbent());
-                break;
-
-        case cheetah:
-        case cheetah_plus:
-                phys_page = cheetah_get_litlb_data(sparc64_highest_locked_tlbent());
-                break;
-        };
+                             : "r" (0), "r" (PRIMARY_CONTEXT),
+                               "i" (ASI_DMMU));
+}
 
-        phys_page &= _PAGE_PADDR;
-        phys_page += ((unsigned long)&prom_boot_page -
-                      (unsigned long)KERNBASE);
+static void lock_remap_func_page(unsigned long phys_page)
+{
+        unsigned long tte_data = (phys_page | pgprot_val(PAGE_KERNEL));
 
         if (tlb_type == spitfire) {
                 /* Lock this into i/d tlb entry 59 */
@@ -478,13 +491,12 @@ static void inherit_prom_mappings(void)
                         "stxa   %0, [%1] %6\n\t"
                         "membar #Sync\n\t"
                         "flush  %%g6"
-                        : : "r" (phys_page | _PAGE_VALID | _PAGE_SZ8K | _PAGE_CP |
-                                 _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W),
-                        "r" (59 << 3), "r" (TLB_TAG_ACCESS),
-                        "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS),
-                        "i" (ASI_IMMU), "i" (ASI_ITLB_DATA_ACCESS)
-                        : "memory");
-        } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
+                : /* no outputs */
+                : "r" (tte_data), "r" (59 << 3), "r" (TLB_TAG_ACCESS),
+                  "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS),
+                  "i" (ASI_IMMU), "i" (ASI_ITLB_DATA_ACCESS)
+                : "memory");
+        } else {
                 /* Lock this into i/d tlb-0 entry 11 */
                 __asm__ __volatile__(
                         "stxa   %%g0, [%2] %3\n\t"
@@ -495,87 +507,80 @@ static void inherit_prom_mappings(void)
                         "stxa   %0, [%1] %6\n\t"
                         "membar #Sync\n\t"
                         "flush  %%g6"
-                        : : "r" (phys_page | _PAGE_VALID | _PAGE_SZ8K | _PAGE_CP |
-                                 _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W),
-                        "r" ((0 << 16) | (11 << 3)), "r" (TLB_TAG_ACCESS),
-                        "i" (ASI_DMMU), "i" (ASI_DTLB_DATA_ACCESS),
-                        "i" (ASI_IMMU), "i" (ASI_ITLB_DATA_ACCESS)
+                        : /* no outputs */
+                        : "r" (tte_data), "r" ((0 << 16) | (11 << 3)),
+                          "r" (TLB_TAG_ACCESS), "i" (ASI_DMMU),
+                          "i" (ASI_DTLB_DATA_ACCESS), "i" (ASI_IMMU),
+                          "i" (ASI_ITLB_DATA_ACCESS)
                         : "memory");
-        } else {
-                /* Implement me :-) */
-                BUG();
         }
+}
+
+static void remap_kernel(void)
+{
+        unsigned long phys_page, tte_vaddr, tte_data;
+        void (*remap_func)(unsigned long, unsigned long, int);
+        int tlb_ent = sparc64_highest_locked_tlbent();
+
+        early_spitfire_errata32();
+
+        if (tlb_type == spitfire)
+                phys_page = spitfire_get_dtlb_data(tlb_ent);
+        else
+                phys_page = cheetah_get_ldtlb_data(tlb_ent);
+
+        phys_page &= _PAGE_PADDR;
+        phys_page += ((unsigned long)&prom_boot_page -
+                      (unsigned long)KERNBASE);
+
+        lock_remap_func_page(phys_page);
 
         tte_vaddr = (unsigned long) KERNBASE;
 
-        /* Spitfire Errata #32 workaround */
-        /* NOTE: Using plain zero for the context value is
-         *       correct here, we are not using the Linux trap
-         *       tables yet so we should not use the special
-         *       UltraSPARC-III+ page size encodings yet.
-         */
-        __asm__ __volatile__("stxa      %0, [%1] %2\n\t"
-                             "flush     %%g6"
-                             : /* No outputs */
-                             : "r" (0),
-                             "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));
+        early_spitfire_errata32();
 
         if (tlb_type == spitfire)
-                tte_data = spitfire_get_dtlb_data(sparc64_highest_locked_tlbent());
+                tte_data = spitfire_get_dtlb_data(tlb_ent);
         else
-                tte_data = cheetah_get_ldtlb_data(sparc64_highest_locked_tlbent());
+                tte_data = cheetah_get_ldtlb_data(tlb_ent);
 
         kern_locked_tte_data = tte_data;
 
         remap_func = (void *)  ((unsigned long) &prom_remap -
                                 (unsigned long) &prom_boot_page);
 
+        early_spitfire_errata32();
 
-        /* Spitfire Errata #32 workaround */
-        /* NOTE: Using plain zero for the context value is
-         *       correct here, we are not using the Linux trap
-         *       tables yet so we should not use the special
-         *       UltraSPARC-III+ page size encodings yet.
-         */
-        __asm__ __volatile__("stxa      %0, [%1] %2\n\t"
-                             "flush     %%g6"
-                             : /* No outputs */
-                             : "r" (0),
-                             "r" (PRIMARY_CONTEXT), "i" (ASI_DMMU));
-
-        remap_func((tlb_type == spitfire ?
-                    (spitfire_get_dtlb_data(sparc64_highest_locked_tlbent()) & _PAGE_PADDR) :
-                    (cheetah_get_litlb_data(sparc64_highest_locked_tlbent()) & _PAGE_PADDR)),
-                   (unsigned long) KERNBASE,
-                   prom_get_mmu_ihandle());
-
+        phys_page = tte_data & _PAGE_PADDR;
+        remap_func(phys_page, KERNBASE, prom_get_mmu_ihandle());
         if (bigkernel)
-                remap_func(((tte_data + 0x400000) & _PAGE_PADDR),
-                        (unsigned long) KERNBASE + 0x400000, prom_get_mmu_ihandle());
+                remap_func(phys_page + 0x400000,
+                           KERNBASE + 0x400000,
+                           prom_get_mmu_ihandle());
 
         /* Flush out that temporary mapping. */
         spitfire_flush_dtlb_nucleus_page(0x0);
         spitfire_flush_itlb_nucleus_page(0x0);
 
         /* Now lock us back into the TLBs via OBP. */
-        prom_dtlb_load(sparc64_highest_locked_tlbent(), tte_data, tte_vaddr);
-        prom_itlb_load(sparc64_highest_locked_tlbent(), tte_data, tte_vaddr);
+        prom_dtlb_load(tlb_ent, tte_data, tte_vaddr);
+        prom_itlb_load(tlb_ent, tte_data, tte_vaddr);
         if (bigkernel) {
-                prom_dtlb_load(sparc64_highest_locked_tlbent()-1, tte_data + 0x400000, 
-                                                                tte_vaddr + 0x400000);
-                prom_itlb_load(sparc64_highest_locked_tlbent()-1, tte_data + 0x400000, 
-                                                                tte_vaddr + 0x400000);
+                prom_dtlb_load(tlb_ent - 1,
+                               tte_data + 0x400000, 
+                               tte_vaddr + 0x400000);
+                prom_itlb_load(tlb_ent - 1,
+                               tte_data + 0x400000, 
+                               tte_vaddr + 0x400000);
         }
+}
 
-        /* Re-read translations property. */
-        if ((n = prom_getproperty(node, "translations",
-                                  (char *)&prom_trans[0], tsz)) == -1) {
-                prom_printf("prom_mappings: Can't reread prom_trans.\n");
-                prom_halt();
-        }
-        n = n / sizeof(struct linux_prom_translation);
+static void readjust_prom_translations(void)
+{
+        int nents, i;
 
-        for (i = 0; i < n; i++) {
+        nents = read_obp_translations();
+        for (i = 0; i < nents; i++) {
                 unsigned long vaddr = prom_trans[i].virt;
                 unsigned long size = prom_trans[i].size;
 
@@ -601,6 +606,20 @@ static void inherit_prom_mappings(void)
                         }
                 }
         }
+}
+
+static void inherit_prom_mappings(void)
+{
+        int n;
+
+        n = read_obp_translations();
+        build_obp_pgtable(n);
+
+        /* Now fixup OBP's idea about where we really are mapped. */
+        prom_printf("Remapping the kernel... ");
+        remap_kernel();
+
+        readjust_prom_translations();
 
         prom_printf("done.\n");