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-rw-r--r--arch/powerpc/platforms/iseries/htab.c254
1 files changed, 254 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/iseries/htab.c b/arch/powerpc/platforms/iseries/htab.c
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+++ b/arch/powerpc/platforms/iseries/htab.c
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+/*
+ * iSeries hashtable management.
+ * Derived from pSeries_htab.c
+ *
+ * SMP scalability work:
+ * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <asm/machdep.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/abs_addr.h>
+#include <linux/spinlock.h>
+
+#include "call_hpt.h"
+
+static spinlock_t iSeries_hlocks[64] __cacheline_aligned_in_smp =
+ { [0 ... 63] = SPIN_LOCK_UNLOCKED};
+
+/*
+ * Very primitive algorithm for picking up a lock
+ */
+static inline void iSeries_hlock(unsigned long slot)
+{
+ if (slot & 0x8)
+ slot = ~slot;
+ spin_lock(&iSeries_hlocks[(slot >> 4) & 0x3f]);
+}
+
+static inline void iSeries_hunlock(unsigned long slot)
+{
+ if (slot & 0x8)
+ slot = ~slot;
+ spin_unlock(&iSeries_hlocks[(slot >> 4) & 0x3f]);
+}
+
+long iSeries_hpte_insert(unsigned long hpte_group, unsigned long va,
+ unsigned long pa, unsigned long rflags,
+ unsigned long vflags, int psize)
+{
+ long slot;
+ hpte_t lhpte;
+ int secondary = 0;
+
+ BUG_ON(psize != MMU_PAGE_4K);
+
+ /*
+ * The hypervisor tries both primary and secondary.
+ * If we are being called to insert in the secondary,
+ * it means we have already tried both primary and secondary,
+ * so we return failure immediately.
+ */
+ if (vflags & HPTE_V_SECONDARY)
+ return -1;
+
+ iSeries_hlock(hpte_group);
+
+ slot = HvCallHpt_findValid(&lhpte, va >> HW_PAGE_SHIFT);
+ if (unlikely(lhpte.v & HPTE_V_VALID)) {
+ if (vflags & HPTE_V_BOLTED) {
+ HvCallHpt_setSwBits(slot, 0x10, 0);
+ HvCallHpt_setPp(slot, PP_RWXX);
+ iSeries_hunlock(hpte_group);
+ if (slot < 0)
+ return 0x8 | (slot & 7);
+ else
+ return slot & 7;
+ }
+ BUG();
+ }
+
+ if (slot == -1) { /* No available entry found in either group */
+ iSeries_hunlock(hpte_group);
+ return -1;
+ }
+
+ if (slot < 0) { /* MSB set means secondary group */
+ vflags |= HPTE_V_SECONDARY;
+ secondary = 1;
+ slot &= 0x7fffffffffffffff;
+ }
+
+
+ lhpte.v = hpte_encode_v(va, MMU_PAGE_4K) | vflags | HPTE_V_VALID;
+ lhpte.r = hpte_encode_r(phys_to_abs(pa), MMU_PAGE_4K) | rflags;
+
+ /* Now fill in the actual HPTE */
+ HvCallHpt_addValidate(slot, secondary, &lhpte);
+
+ iSeries_hunlock(hpte_group);
+
+ return (secondary << 3) | (slot & 7);
+}
+
+static unsigned long iSeries_hpte_getword0(unsigned long slot)
+{
+ hpte_t hpte;
+
+ HvCallHpt_get(&hpte, slot);
+ return hpte.v;
+}
+
+static long iSeries_hpte_remove(unsigned long hpte_group)
+{
+ unsigned long slot_offset;
+ int i;
+ unsigned long hpte_v;
+
+ /* Pick a random slot to start at */
+ slot_offset = mftb() & 0x7;
+
+ iSeries_hlock(hpte_group);
+
+ for (i = 0; i < HPTES_PER_GROUP; i++) {
+ hpte_v = iSeries_hpte_getword0(hpte_group + slot_offset);
+
+ if (! (hpte_v & HPTE_V_BOLTED)) {
+ HvCallHpt_invalidateSetSwBitsGet(hpte_group +
+ slot_offset, 0, 0);
+ iSeries_hunlock(hpte_group);
+ return i;
+ }
+
+ slot_offset++;
+ slot_offset &= 0x7;
+ }
+
+ iSeries_hunlock(hpte_group);
+
+ return -1;
+}
+
+/*
+ * The HyperVisor expects the "flags" argument in this form:
+ * bits 0..59 : reserved
+ * bit 60 : N
+ * bits 61..63 : PP2,PP1,PP0
+ */
+static long iSeries_hpte_updatepp(unsigned long slot, unsigned long newpp,
+ unsigned long va, int psize, int local)
+{
+ hpte_t hpte;
+ unsigned long want_v;
+
+ iSeries_hlock(slot);
+
+ HvCallHpt_get(&hpte, slot);
+ want_v = hpte_encode_v(va, MMU_PAGE_4K);
+
+ if (HPTE_V_COMPARE(hpte.v, want_v) && (hpte.v & HPTE_V_VALID)) {
+ /*
+ * Hypervisor expects bits as NPPP, which is
+ * different from how they are mapped in our PP.
+ */
+ HvCallHpt_setPp(slot, (newpp & 0x3) | ((newpp & 0x4) << 1));
+ iSeries_hunlock(slot);
+ return 0;
+ }
+ iSeries_hunlock(slot);
+
+ return -1;
+}
+
+/*
+ * Functions used to find the PTE for a particular virtual address.
+ * Only used during boot when bolting pages.
+ *
+ * Input : vpn : virtual page number
+ * Output: PTE index within the page table of the entry
+ * -1 on failure
+ */
+static long iSeries_hpte_find(unsigned long vpn)
+{
+ hpte_t hpte;
+ long slot;
+
+ /*
+ * The HvCallHpt_findValid interface is as follows:
+ * 0xffffffffffffffff : No entry found.
+ * 0x00000000xxxxxxxx : Entry found in primary group, slot x
+ * 0x80000000xxxxxxxx : Entry found in secondary group, slot x
+ */
+ slot = HvCallHpt_findValid(&hpte, vpn);
+ if (hpte.v & HPTE_V_VALID) {
+ if (slot < 0) {
+ slot &= 0x7fffffffffffffff;
+ slot = -slot;
+ }
+ } else
+ slot = -1;
+ return slot;
+}
+
+/*
+ * Update the page protection bits. Intended to be used to create
+ * guard pages for kernel data structures on pages which are bolted
+ * in the HPT. Assumes pages being operated on will not be stolen.
+ * Does not work on large pages.
+ *
+ * No need to lock here because we should be the only user.
+ */
+static void iSeries_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
+ int psize)
+{
+ unsigned long vsid,va,vpn;
+ long slot;
+
+ BUG_ON(psize != MMU_PAGE_4K);
+
+ vsid = get_kernel_vsid(ea);
+ va = (vsid << 28) | (ea & 0x0fffffff);
+ vpn = va >> HW_PAGE_SHIFT;
+ slot = iSeries_hpte_find(vpn);
+ if (slot == -1)
+ panic("updateboltedpp: Could not find page to bolt\n");
+ HvCallHpt_setPp(slot, newpp);
+}
+
+static void iSeries_hpte_invalidate(unsigned long slot, unsigned long va,
+ int psize, int local)
+{
+ unsigned long hpte_v;
+ unsigned long avpn = va >> 23;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ iSeries_hlock(slot);
+
+ hpte_v = iSeries_hpte_getword0(slot);
+
+ if ((HPTE_V_AVPN_VAL(hpte_v) == avpn) && (hpte_v & HPTE_V_VALID))
+ HvCallHpt_invalidateSetSwBitsGet(slot, 0, 0);
+
+ iSeries_hunlock(slot);
+
+ local_irq_restore(flags);
+}
+
+void hpte_init_iSeries(void)
+{
+ ppc_md.hpte_invalidate = iSeries_hpte_invalidate;
+ ppc_md.hpte_updatepp = iSeries_hpte_updatepp;
+ ppc_md.hpte_updateboltedpp = iSeries_hpte_updateboltedpp;
+ ppc_md.hpte_insert = iSeries_hpte_insert;
+ ppc_md.hpte_remove = iSeries_hpte_remove;
+
+ htab_finish_init();
+}