diff options
Diffstat (limited to 'arch/powerpc/platforms/iseries/htab.c')
| -rw-r--r-- | arch/powerpc/platforms/iseries/htab.c | 256 |
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 00000000000..431b22767d0 --- /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(); +} |