powerpc/ps3: Rework htab code to remove ioremap

Rework the PS3 MMU hash table code to remove the need to ioremap the
hash table by using the HV calls lv1_insert_htab_entry() and
lv1_read_htab_entries().

This fixes a runtime failure on the PS3 introduced by the powerpc
ioremap_prot rework of commit a1f242ff460e4b50a045fa237c3c56cce9eabf83
("powerpc ioremap_prot").

Signed-off-by: Masakazu Mokuno <mokuno@sm.sony.co.jp>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 91 insertions, 179 deletions

diff --git a/arch/powerpc/platforms/ps3/htab.c b/arch/powerpc/platforms/ps3/htab.c
index 1cf901fa903..6eb1d4d182c 100644
--- a/arch/powerpc/platforms/ps3/htab.c
+++ b/arch/powerpc/platforms/ps3/htab.c
@@ -29,138 +29,75 @@
 
 #include "platform.h"
 
-#if defined(DEBUG)
-#define DBG udbg_printf
-#else
-#define DBG pr_debug
-#endif
-
-static struct hash_pte *htab;
-static unsigned long htab_addr;
-static unsigned char *bolttab;
-static unsigned char *inusetab;
-
-static DEFINE_SPINLOCK(ps3_bolttab_lock);
-
-#define debug_dump_hpte(_a, _b, _c, _d, _e, _f, _g) \
-        _debug_dump_hpte(_a, _b, _c, _d, _e, _f, _g, __func__, __LINE__)
-static void _debug_dump_hpte(unsigned long pa, unsigned long va,
-        unsigned long group, unsigned long bitmap, struct hash_pte lhpte,
-        int psize, unsigned long slot, const char* func, int line)
-{
-        DBG("%s:%d: pa     = %lxh\n", func, line, pa);
-        DBG("%s:%d: lpar   = %lxh\n", func, line,
-                ps3_mm_phys_to_lpar(pa));
-        DBG("%s:%d: va     = %lxh\n", func, line, va);
-        DBG("%s:%d: group  = %lxh\n", func, line, group);
-        DBG("%s:%d: bitmap = %lxh\n", func, line, bitmap);
-        DBG("%s:%d: hpte.v = %lxh\n", func, line, lhpte.v);
-        DBG("%s:%d: hpte.r = %lxh\n", func, line, lhpte.r);
-        DBG("%s:%d: psize  = %xh\n", func, line, psize);
-        DBG("%s:%d: slot   = %lxh\n", func, line, slot);
-}
+/**
+ * enum lpar_vas_id - id of LPAR virtual address space.
+ * @lpar_vas_id_current: Current selected virtual address space
+ *
+ * Identify the target LPAR address space.
+ */
+
+enum ps3_lpar_vas_id {
+        PS3_LPAR_VAS_ID_CURRENT = 0,
+};
+
+
+static DEFINE_SPINLOCK(ps3_htab_lock);
 
 static long ps3_hpte_insert(unsigned long hpte_group, unsigned long va,
         unsigned long pa, unsigned long rflags, unsigned long vflags,
         int psize, int ssize)
 {
-        unsigned long slot;
-        struct hash_pte lhpte;
-        int secondary = 0;
-        unsigned long result;
-        unsigned long bitmap;
+        int result;
+        u64 hpte_v, hpte_r;
+        u64 inserted_index;
+        u64 evicted_v, evicted_r;
+        u64 hpte_v_array[4], hpte_rs;
         unsigned long flags;
-        unsigned long p_pteg, s_pteg, b_index, b_mask, cb, ci;
-
-        vflags &= ~HPTE_V_SECONDARY; /* this bit is ignored */
-
-        lhpte.v = hpte_encode_v(va, psize, MMU_SEGSIZE_256M) |
-                vflags | HPTE_V_VALID;
-        lhpte.r = hpte_encode_r(ps3_mm_phys_to_lpar(pa), psize) | rflags;
-
-        p_pteg = hpte_group / HPTES_PER_GROUP;
-        s_pteg = ~p_pteg & htab_hash_mask;
-
-        spin_lock_irqsave(&ps3_bolttab_lock, flags);
-
-        BUG_ON(bolttab[p_pteg] == 0xff && bolttab[s_pteg] == 0xff);
+        long ret = -1;
 
-        bitmap = (inusetab[p_pteg] << 8) | inusetab[s_pteg];
+        /*
+         * lv1_insert_htab_entry() will search for victim
+         * entry in both primary and secondary pte group
+         */
+        vflags &= ~HPTE_V_SECONDARY;
 
-        if (bitmap == 0xffff) {
-                /*
-                 * PTEG is full. Search for victim.
-                 */
-                bitmap &= ~((bolttab[p_pteg] << 8) | bolttab[s_pteg]);
-                do {
-                        ci = mftb() & 15;
-                        cb = 0x8000UL >> ci;
-                } while ((cb & bitmap) == 0);
-        } else {
-                /*
-                 * search free slot in hardware order
-                 *      [primary]       0, 2, 4, 6, 1, 3, 5, 7
-                 *      [secondary]     0, 2, 4, 6, 1, 3, 5, 7
-                 */
-                for (ci = 0; ci < HPTES_PER_GROUP; ci += 2) {
-                        cb = 0x8000UL >> ci;
-                        if ((cb & bitmap) == 0)
-                                goto found;
-                }
-                for (ci = 1; ci < HPTES_PER_GROUP; ci += 2) {
-                        cb = 0x8000UL >> ci;
-                        if ((cb & bitmap) == 0)
-                                goto found;
-                }
-                for (ci = HPTES_PER_GROUP; ci < HPTES_PER_GROUP*2; ci += 2) {
-                        cb = 0x8000UL >> ci;
-                        if ((cb & bitmap) == 0)
-                                goto found;
-                }
-                for (ci = HPTES_PER_GROUP+1; ci < HPTES_PER_GROUP*2; ci += 2) {
-                        cb = 0x8000UL >> ci;
-                        if ((cb & bitmap) == 0)
-                                goto found;
-                }
-        }
+        hpte_v = hpte_encode_v(va, psize, ssize) | vflags | HPTE_V_VALID;
+        hpte_r = hpte_encode_r(ps3_mm_phys_to_lpar(pa), psize) | rflags;
 
-found:
-        if (ci < HPTES_PER_GROUP) {
-                slot = p_pteg * HPTES_PER_GROUP + ci;
-        } else {
-                slot = s_pteg * HPTES_PER_GROUP + (ci & 7);
-                /* lhpte.dw0.dw0.h = 1; */
-                vflags |= HPTE_V_SECONDARY;
-                lhpte.v |= HPTE_V_SECONDARY;
-        }
+        spin_lock_irqsave(&ps3_htab_lock, flags);
 
-        result = lv1_write_htab_entry(0, slot, lhpte.v, lhpte.r);
+        /* talk hvc to replace entries BOLTED == 0 */
+        result = lv1_insert_htab_entry(PS3_LPAR_VAS_ID_CURRENT, hpte_group,
+                                       hpte_v, hpte_r,
+                                       HPTE_V_BOLTED, 0,
+                                       &inserted_index,
+                                       &evicted_v, &evicted_r);
 
         if (result) {
-                debug_dump_hpte(pa, va, hpte_group, bitmap, lhpte, psize, slot);
+                /* all entries bolted !*/
+                pr_info("%s:result=%d va=%lx pa=%lx ix=%lx v=%lx r=%lx\n",
+                        __func__, result, va, pa, hpte_group, hpte_v, hpte_r);
                 BUG();
         }
 
         /*
-         * If used slot is not in primary HPTE group,
-         * the slot should be in secondary HPTE group.
+         * see if the entry is inserted into secondary pteg
          */
+        result = lv1_read_htab_entries(PS3_LPAR_VAS_ID_CURRENT,
+                                       inserted_index & ~0x3UL,
+                                       &hpte_v_array[0], &hpte_v_array[1],
+                                       &hpte_v_array[2], &hpte_v_array[3],
+                                       &hpte_rs);
+        BUG_ON(result);
 
-        if ((hpte_group ^ slot) & ~(HPTES_PER_GROUP - 1)) {
-                secondary = 1;
-                b_index = s_pteg;
-        } else {
-                secondary = 0;
-                b_index = p_pteg;
-        }
+        if (hpte_v_array[inserted_index % 4] & HPTE_V_SECONDARY)
+                ret = (inserted_index & 7) | (1 << 3);
+        else
+                ret = inserted_index & 7;
 
-        b_mask = (lhpte.v & HPTE_V_BOLTED) ? 1 << 7 : 0 << 7;
-        bolttab[b_index] |= b_mask >> (slot & 7);
-        b_mask = 1 << 7;
-        inusetab[b_index] |= b_mask >> (slot & 7);
-        spin_unlock_irqrestore(&ps3_bolttab_lock, flags);
+        spin_unlock_irqrestore(&ps3_htab_lock, flags);
 
-        return (slot & 7) | (secondary << 3);
+        return ret;
 }
 
 static long ps3_hpte_remove(unsigned long hpte_group)
@@ -172,39 +109,48 @@ static long ps3_hpte_remove(unsigned long hpte_group)
 static long ps3_hpte_updatepp(unsigned long slot, unsigned long newpp,
         unsigned long va, int psize, int ssize, int local)
 {
+        int result;
+        u64 hpte_v, want_v, hpte_rs;
+        u64 hpte_v_array[4];
         unsigned long flags;
-        unsigned long result;
-        unsigned long pteg, bit;
-        unsigned long hpte_v, want_v;
+        long ret;
 
-        want_v = hpte_encode_v(va, psize, MMU_SEGSIZE_256M);
+        want_v = hpte_encode_v(va, psize, ssize);
 
-        spin_lock_irqsave(&ps3_bolttab_lock, flags);
+        spin_lock_irqsave(&ps3_htab_lock, flags);
 
-        hpte_v = htab[slot].v;
-        if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID)) {
-                spin_unlock_irqrestore(&ps3_bolttab_lock, flags);
-
-                /* ps3_hpte_insert() will be used to update PTE */
-                return -1;
-        }
-
-        result = lv1_write_htab_entry(0, slot, 0, 0);
+        result = lv1_read_htab_entries(PS3_LPAR_VAS_ID_CURRENT, slot & ~0x3UL,
+                                       &hpte_v_array[0], &hpte_v_array[1],
+                                       &hpte_v_array[2], &hpte_v_array[3],
+                                       &hpte_rs);
 
         if (result) {
-                DBG("%s: va=%lx slot=%lx psize=%d result = %ld (0x%lx)\n",
-                       __func__, va, slot, psize, result, result);
+                pr_info("%s: res=%d read va=%lx slot=%lx psize=%d\n",
+                        __func__, result, va, slot, psize);
                 BUG();
         }
 
-        pteg = slot / HPTES_PER_GROUP;
-        bit = slot % HPTES_PER_GROUP;
-        inusetab[pteg] &= ~(0x80 >> bit);
+        hpte_v = hpte_v_array[slot % 4];
 
-        spin_unlock_irqrestore(&ps3_bolttab_lock, flags);
+        /*
+         * As lv1_read_htab_entries() does not give us the RPN, we can
+         * not synthesize the new hpte_r value here, and therefore can
+         * not update the hpte with lv1_insert_htab_entry(), so we
+         * insted invalidate it and ask the caller to update it via
+         * ps3_hpte_insert() by returning a -1 value.
+         */
+        if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID)) {
+                /* not found */
+                ret = -1;
+        } else {
+                /* entry found, just invalidate it */
+                result = lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT,
+                                              slot, 0, 0);
+                ret = -1;
+        }
 
-        /* ps3_hpte_insert() will be used to update PTE */
-        return -1;
+        spin_unlock_irqrestore(&ps3_htab_lock, flags);
+        return ret;
 }
 
 static void ps3_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
@@ -217,45 +163,35 @@ static void ps3_hpte_invalidate(unsigned long slot, unsigned long va,
         int psize, int ssize, int local)
 {
         unsigned long flags;
-        unsigned long result;
-        unsigned long pteg, bit;
+        int result;
+
+        spin_lock_irqsave(&ps3_htab_lock, flags);
 
-        spin_lock_irqsave(&ps3_bolttab_lock, flags);
-        result = lv1_write_htab_entry(0, slot, 0, 0);
+        result = lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT, slot, 0, 0);
 
         if (result) {
-                DBG("%s: va=%lx slot=%lx psize=%d result = %ld (0x%lx)\n",
-                       __func__, va, slot, psize, result, result);
+                pr_info("%s: res=%d va=%lx slot=%lx psize=%d\n",
+                        __func__, result, va, slot, psize);
                 BUG();
         }
 
-        pteg = slot / HPTES_PER_GROUP;
-        bit = slot % HPTES_PER_GROUP;
-        inusetab[pteg] &= ~(0x80 >> bit);
-        spin_unlock_irqrestore(&ps3_bolttab_lock, flags);
+        spin_unlock_irqrestore(&ps3_htab_lock, flags);
 }
 
 static void ps3_hpte_clear(void)
 {
-        int result;
-
-        DBG(" -> %s:%d\n", __func__, __LINE__);
+        unsigned long hpte_count = (1UL << ppc64_pft_size) >> 4;
+        u64 i;
 
-        result = lv1_unmap_htab(htab_addr);
-        BUG_ON(result);
+        for (i = 0; i < hpte_count; i++)
+                lv1_write_htab_entry(PS3_LPAR_VAS_ID_CURRENT, i, 0, 0);
 
         ps3_mm_shutdown();
         ps3_mm_vas_destroy();
-
-        DBG(" <- %s:%d\n", __func__, __LINE__);
 }
 
 void __init ps3_hpte_init(unsigned long htab_size)
 {
-        long bitmap_size;
-
-        DBG(" -> %s:%d\n", __func__, __LINE__);
-
         ppc_md.hpte_invalidate = ps3_hpte_invalidate;
         ppc_md.hpte_updatepp = ps3_hpte_updatepp;
         ppc_md.hpte_updateboltedpp = ps3_hpte_updateboltedpp;
@@ -264,28 +200,5 @@ void __init ps3_hpte_init(unsigned long htab_size)
         ppc_md.hpte_clear_all = ps3_hpte_clear;
 
         ppc64_pft_size = __ilog2(htab_size);
-
-        bitmap_size = htab_size / sizeof(struct hash_pte) / 8;
-
-        bolttab = __va(lmb_alloc(bitmap_size, 1));
-        inusetab = __va(lmb_alloc(bitmap_size, 1));
-
-        memset(bolttab, 0, bitmap_size);
-        memset(inusetab, 0, bitmap_size);
-
-        DBG(" <- %s:%d\n", __func__, __LINE__);
 }
 
-void __init ps3_map_htab(void)
-{
-        long result;
-        unsigned long htab_size = (1UL << ppc64_pft_size);
-
-        result = lv1_map_htab(0, &htab_addr);
-
-        htab = (__force struct hash_pte *)ioremap_flags(htab_addr, htab_size,
-                                            pgprot_val(PAGE_READONLY_X));
-
-        DBG("%s:%d: lpar %016lxh, virt %016lxh\n", __func__, __LINE__,
-                htab_addr, (unsigned long)htab);
-}
diff --git a/arch/powerpc/platforms/ps3/setup.c b/arch/powerpc/platforms/ps3/setup.c
index a413abbd412..77bc330263c 100644
--- a/arch/powerpc/platforms/ps3/setup.c
+++ b/arch/powerpc/platforms/ps3/setup.c
@@ -201,7 +201,6 @@ static void __init ps3_setup_arch(void)
                ps3_firmware_version.rev);
 
         ps3_spu_set_platform();
-        ps3_map_htab();
 
 #ifdef CONFIG_SMP
         smp_init_ps3();