powerpc: Move iSeries_htab.c to powerpc/platforms/iseries

And rename it to htab.c

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

1 files changed, 256 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/iseries/htab.c b/arch/powerpc/platforms/iseries/htab.c
new file mode 100644
index 000000000000..431b22767d06
--- /dev/null
+++ b/arch/powerpc/platforms/iseries/htab.c
@@ -0,0 +1,256 @@
+/*
+ * 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/iSeries/HvCallHpt.h>
+#include <asm/abs_addr.h>
+#include <linux/spinlock.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]);
+}
+
+static long iSeries_hpte_insert(unsigned long hpte_group, unsigned long va,
+				unsigned long prpn, unsigned long vflags,
+				unsigned long rflags)
+{
+	unsigned long arpn;
+	long slot;
+	hpte_t lhpte;
+	int secondary = 0;
+
+	/*
+	 * 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 >> PAGE_SHIFT);
+	BUG_ON(lhpte.v & HPTE_V_VALID);
+
+	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_VALID;
+		secondary = 1;
+		slot &= 0x7fffffffffffffff;
+	}
+
+	arpn = phys_to_abs(prpn << PAGE_SHIFT) >> PAGE_SHIFT;
+
+	lhpte.v = (va >> 23) << HPTE_V_AVPN_SHIFT | vflags | HPTE_V_VALID;
+	lhpte.r = (arpn << HPTE_R_RPN_SHIFT) | rflags;
+
+	/* Now fill in the actual HPTE */
+	HvCallHpt_addValidate(slot, secondary, &lhpte);
+
+	iSeries_hunlock(hpte_group);
+
+	return (secondary << 3) | (slot & 7);
+}
+
+long iSeries_hpte_bolt_or_insert(unsigned long hpte_group,
+		unsigned long va, unsigned long prpn, unsigned long vflags,
+		unsigned long rflags)
+{
+	long slot;
+	hpte_t lhpte;
+
+	slot = HvCallHpt_findValid(&lhpte, va >> PAGE_SHIFT);
+
+	if (lhpte.v & HPTE_V_VALID) {
+		/* Bolt the existing HPTE */
+		HvCallHpt_setSwBits(slot, 0x10, 0);
+		HvCallHpt_setPp(slot, PP_RWXX);
+		return 0;
+	}
+
+	return iSeries_hpte_insert(hpte_group, va, prpn, vflags, rflags);
+}
+
+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 large, int local)
+{
+	hpte_t hpte;
+	unsigned long avpn = va >> 23;
+
+	iSeries_hlock(slot);
+
+	HvCallHpt_get(&hpte, slot);
+	if ((HPTE_V_AVPN_VAL(hpte.v) == avpn) && (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)
+{
+	unsigned long vsid,va,vpn;
+	long slot;
+
+	vsid = get_kernel_vsid(ea);
+	va = (vsid << 28) | (ea & 0x0fffffff);
+	vpn = va >> 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 large, 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();
+}