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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/mm/tlb_nohash.c
Initial import
Diffstat (limited to 'arch/powerpc/mm/tlb_nohash.c')
-rw-r--r--arch/powerpc/mm/tlb_nohash.c760
1 files changed, 760 insertions, 0 deletions
diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
new file mode 100644
index 000000000..cbd3d0698
--- /dev/null
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -0,0 +1,760 @@
+/*
+ * This file contains the routines for TLB flushing.
+ * On machines where the MMU does not use a hash table to store virtual to
+ * physical translations (ie, SW loaded TLBs or Book3E compilant processors,
+ * this does -not- include 603 however which shares the implementation with
+ * hash based processors)
+ *
+ * -- BenH
+ *
+ * Copyright 2008,2009 Ben Herrenschmidt <benh@kernel.crashing.org>
+ * IBM Corp.
+ *
+ * Derived from arch/ppc/mm/init.c:
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * 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 <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/preempt.h>
+#include <linux/spinlock.h>
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
+#include <linux/hugetlb.h>
+
+#include <asm/tlbflush.h>
+#include <asm/tlb.h>
+#include <asm/code-patching.h>
+#include <asm/hugetlb.h>
+#include <asm/paca.h>
+
+#include "mmu_decl.h"
+
+/*
+ * This struct lists the sw-supported page sizes. The hardawre MMU may support
+ * other sizes not listed here. The .ind field is only used on MMUs that have
+ * indirect page table entries.
+ */
+#ifdef CONFIG_PPC_BOOK3E_MMU
+#ifdef CONFIG_PPC_FSL_BOOK3E
+struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
+ [MMU_PAGE_4K] = {
+ .shift = 12,
+ .enc = BOOK3E_PAGESZ_4K,
+ },
+ [MMU_PAGE_2M] = {
+ .shift = 21,
+ .enc = BOOK3E_PAGESZ_2M,
+ },
+ [MMU_PAGE_4M] = {
+ .shift = 22,
+ .enc = BOOK3E_PAGESZ_4M,
+ },
+ [MMU_PAGE_16M] = {
+ .shift = 24,
+ .enc = BOOK3E_PAGESZ_16M,
+ },
+ [MMU_PAGE_64M] = {
+ .shift = 26,
+ .enc = BOOK3E_PAGESZ_64M,
+ },
+ [MMU_PAGE_256M] = {
+ .shift = 28,
+ .enc = BOOK3E_PAGESZ_256M,
+ },
+ [MMU_PAGE_1G] = {
+ .shift = 30,
+ .enc = BOOK3E_PAGESZ_1GB,
+ },
+};
+#else
+struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT] = {
+ [MMU_PAGE_4K] = {
+ .shift = 12,
+ .ind = 20,
+ .enc = BOOK3E_PAGESZ_4K,
+ },
+ [MMU_PAGE_16K] = {
+ .shift = 14,
+ .enc = BOOK3E_PAGESZ_16K,
+ },
+ [MMU_PAGE_64K] = {
+ .shift = 16,
+ .ind = 28,
+ .enc = BOOK3E_PAGESZ_64K,
+ },
+ [MMU_PAGE_1M] = {
+ .shift = 20,
+ .enc = BOOK3E_PAGESZ_1M,
+ },
+ [MMU_PAGE_16M] = {
+ .shift = 24,
+ .ind = 36,
+ .enc = BOOK3E_PAGESZ_16M,
+ },
+ [MMU_PAGE_256M] = {
+ .shift = 28,
+ .enc = BOOK3E_PAGESZ_256M,
+ },
+ [MMU_PAGE_1G] = {
+ .shift = 30,
+ .enc = BOOK3E_PAGESZ_1GB,
+ },
+};
+#endif /* CONFIG_FSL_BOOKE */
+
+static inline int mmu_get_tsize(int psize)
+{
+ return mmu_psize_defs[psize].enc;
+}
+#else
+static inline int mmu_get_tsize(int psize)
+{
+ /* This isn't used on !Book3E for now */
+ return 0;
+}
+#endif /* CONFIG_PPC_BOOK3E_MMU */
+
+/* The variables below are currently only used on 64-bit Book3E
+ * though this will probably be made common with other nohash
+ * implementations at some point
+ */
+#ifdef CONFIG_PPC64
+
+int mmu_linear_psize; /* Page size used for the linear mapping */
+int mmu_pte_psize; /* Page size used for PTE pages */
+int mmu_vmemmap_psize; /* Page size used for the virtual mem map */
+int book3e_htw_mode; /* HW tablewalk? Value is PPC_HTW_* */
+unsigned long linear_map_top; /* Top of linear mapping */
+
+
+/*
+ * Number of bytes to add to SPRN_SPRG_TLB_EXFRAME on crit/mcheck/debug
+ * exceptions. This is used for bolted and e6500 TLB miss handlers which
+ * do not modify this SPRG in the TLB miss code; for other TLB miss handlers,
+ * this is set to zero.
+ */
+int extlb_level_exc;
+
+#endif /* CONFIG_PPC64 */
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+/* next_tlbcam_idx is used to round-robin tlbcam entry assignment */
+DEFINE_PER_CPU(int, next_tlbcam_idx);
+EXPORT_PER_CPU_SYMBOL(next_tlbcam_idx);
+#endif
+
+/*
+ * Base TLB flushing operations:
+ *
+ * - flush_tlb_mm(mm) flushes the specified mm context TLB's
+ * - flush_tlb_page(vma, vmaddr) flushes one page
+ * - flush_tlb_range(vma, start, end) flushes a range of pages
+ * - flush_tlb_kernel_range(start, end) flushes kernel pages
+ *
+ * - local_* variants of page and mm only apply to the current
+ * processor
+ */
+
+/*
+ * These are the base non-SMP variants of page and mm flushing
+ */
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+ unsigned int pid;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (pid != MMU_NO_CONTEXT)
+ _tlbil_pid(pid);
+ preempt_enable();
+}
+EXPORT_SYMBOL(local_flush_tlb_mm);
+
+void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
+ int tsize, int ind)
+{
+ unsigned int pid;
+
+ preempt_disable();
+ pid = mm ? mm->context.id : 0;
+ if (pid != MMU_NO_CONTEXT)
+ _tlbil_va(vmaddr, pid, tsize, ind);
+ preempt_enable();
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+ __local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
+ mmu_get_tsize(mmu_virtual_psize), 0);
+}
+EXPORT_SYMBOL(local_flush_tlb_page);
+
+/*
+ * And here are the SMP non-local implementations
+ */
+#ifdef CONFIG_SMP
+
+static DEFINE_RAW_SPINLOCK(tlbivax_lock);
+
+static int mm_is_core_local(struct mm_struct *mm)
+{
+ return cpumask_subset(mm_cpumask(mm),
+ topology_thread_cpumask(smp_processor_id()));
+}
+
+struct tlb_flush_param {
+ unsigned long addr;
+ unsigned int pid;
+ unsigned int tsize;
+ unsigned int ind;
+};
+
+static void do_flush_tlb_mm_ipi(void *param)
+{
+ struct tlb_flush_param *p = param;
+
+ _tlbil_pid(p ? p->pid : 0);
+}
+
+static void do_flush_tlb_page_ipi(void *param)
+{
+ struct tlb_flush_param *p = param;
+
+ _tlbil_va(p->addr, p->pid, p->tsize, p->ind);
+}
+
+
+/* Note on invalidations and PID:
+ *
+ * We snapshot the PID with preempt disabled. At this point, it can still
+ * change either because:
+ * - our context is being stolen (PID -> NO_CONTEXT) on another CPU
+ * - we are invaliating some target that isn't currently running here
+ * and is concurrently acquiring a new PID on another CPU
+ * - some other CPU is re-acquiring a lost PID for this mm
+ * etc...
+ *
+ * However, this shouldn't be a problem as we only guarantee
+ * invalidation of TLB entries present prior to this call, so we
+ * don't care about the PID changing, and invalidating a stale PID
+ * is generally harmless.
+ */
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+ unsigned int pid;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ goto no_context;
+ if (!mm_is_core_local(mm)) {
+ struct tlb_flush_param p = { .pid = pid };
+ /* Ignores smp_processor_id() even if set. */
+ smp_call_function_many(mm_cpumask(mm),
+ do_flush_tlb_mm_ipi, &p, 1);
+ }
+ _tlbil_pid(pid);
+ no_context:
+ preempt_enable();
+}
+EXPORT_SYMBOL(flush_tlb_mm);
+
+void __flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
+ int tsize, int ind)
+{
+ struct cpumask *cpu_mask;
+ unsigned int pid;
+
+ /*
+ * This function as well as __local_flush_tlb_page() must only be called
+ * for user contexts.
+ */
+ if (unlikely(WARN_ON(!mm)))
+ return;
+
+ preempt_disable();
+ pid = mm->context.id;
+ if (unlikely(pid == MMU_NO_CONTEXT))
+ goto bail;
+ cpu_mask = mm_cpumask(mm);
+ if (!mm_is_core_local(mm)) {
+ /* If broadcast tlbivax is supported, use it */
+ if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) {
+ int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL);
+ if (lock)
+ raw_spin_lock(&tlbivax_lock);
+ _tlbivax_bcast(vmaddr, pid, tsize, ind);
+ if (lock)
+ raw_spin_unlock(&tlbivax_lock);
+ goto bail;
+ } else {
+ struct tlb_flush_param p = {
+ .pid = pid,
+ .addr = vmaddr,
+ .tsize = tsize,
+ .ind = ind,
+ };
+ /* Ignores smp_processor_id() even if set in cpu_mask */
+ smp_call_function_many(cpu_mask,
+ do_flush_tlb_page_ipi, &p, 1);
+ }
+ }
+ _tlbil_va(vmaddr, pid, tsize, ind);
+ bail:
+ preempt_enable();
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ if (vma && is_vm_hugetlb_page(vma))
+ flush_hugetlb_page(vma, vmaddr);
+#endif
+
+ __flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
+ mmu_get_tsize(mmu_virtual_psize), 0);
+}
+EXPORT_SYMBOL(flush_tlb_page);
+
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_PPC_47x
+void __init early_init_mmu_47x(void)
+{
+#ifdef CONFIG_SMP
+ unsigned long root = of_get_flat_dt_root();
+ if (of_get_flat_dt_prop(root, "cooperative-partition", NULL))
+ mmu_clear_feature(MMU_FTR_USE_TLBIVAX_BCAST);
+#endif /* CONFIG_SMP */
+}
+#endif /* CONFIG_PPC_47x */
+
+/*
+ * Flush kernel TLB entries in the given range
+ */
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+#ifdef CONFIG_SMP
+ preempt_disable();
+ smp_call_function(do_flush_tlb_mm_ipi, NULL, 1);
+ _tlbil_pid(0);
+ preempt_enable();
+#else
+ _tlbil_pid(0);
+#endif
+}
+EXPORT_SYMBOL(flush_tlb_kernel_range);
+
+/*
+ * Currently, for range flushing, we just do a full mm flush. This should
+ * be optimized based on a threshold on the size of the range, since
+ * some implementation can stack multiple tlbivax before a tlbsync but
+ * for now, we keep it that way
+ */
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+
+{
+ flush_tlb_mm(vma->vm_mm);
+}
+EXPORT_SYMBOL(flush_tlb_range);
+
+void tlb_flush(struct mmu_gather *tlb)
+{
+ flush_tlb_mm(tlb->mm);
+}
+
+/*
+ * Below are functions specific to the 64-bit variant of Book3E though that
+ * may change in the future
+ */
+
+#ifdef CONFIG_PPC64
+
+/*
+ * Handling of virtual linear page tables or indirect TLB entries
+ * flushing when PTE pages are freed
+ */
+void tlb_flush_pgtable(struct mmu_gather *tlb, unsigned long address)
+{
+ int tsize = mmu_psize_defs[mmu_pte_psize].enc;
+
+ if (book3e_htw_mode != PPC_HTW_NONE) {
+ unsigned long start = address & PMD_MASK;
+ unsigned long end = address + PMD_SIZE;
+ unsigned long size = 1UL << mmu_psize_defs[mmu_pte_psize].shift;
+
+ /* This isn't the most optimal, ideally we would factor out the
+ * while preempt & CPU mask mucking around, or even the IPI but
+ * it will do for now
+ */
+ while (start < end) {
+ __flush_tlb_page(tlb->mm, start, tsize, 1);
+ start += size;
+ }
+ } else {
+ unsigned long rmask = 0xf000000000000000ul;
+ unsigned long rid = (address & rmask) | 0x1000000000000000ul;
+ unsigned long vpte = address & ~rmask;
+
+#ifdef CONFIG_PPC_64K_PAGES
+ vpte = (vpte >> (PAGE_SHIFT - 4)) & ~0xfffful;
+#else
+ vpte = (vpte >> (PAGE_SHIFT - 3)) & ~0xffful;
+#endif
+ vpte |= rid;
+ __flush_tlb_page(tlb->mm, vpte, tsize, 0);
+ }
+}
+
+static void setup_page_sizes(void)
+{
+ unsigned int tlb0cfg;
+ unsigned int tlb0ps;
+ unsigned int eptcfg;
+ int i, psize;
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ unsigned int mmucfg = mfspr(SPRN_MMUCFG);
+ int fsl_mmu = mmu_has_feature(MMU_FTR_TYPE_FSL_E);
+
+ if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V1) {
+ unsigned int tlb1cfg = mfspr(SPRN_TLB1CFG);
+ unsigned int min_pg, max_pg;
+
+ min_pg = (tlb1cfg & TLBnCFG_MINSIZE) >> TLBnCFG_MINSIZE_SHIFT;
+ max_pg = (tlb1cfg & TLBnCFG_MAXSIZE) >> TLBnCFG_MAXSIZE_SHIFT;
+
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def;
+ unsigned int shift;
+
+ def = &mmu_psize_defs[psize];
+ shift = def->shift;
+
+ if (shift == 0 || shift & 1)
+ continue;
+
+ /* adjust to be in terms of 4^shift Kb */
+ shift = (shift - 10) >> 1;
+
+ if ((shift >= min_pg) && (shift <= max_pg))
+ def->flags |= MMU_PAGE_SIZE_DIRECT;
+ }
+
+ goto out;
+ }
+
+ if (fsl_mmu && (mmucfg & MMUCFG_MAVN) == MMUCFG_MAVN_V2) {
+ u32 tlb1cfg, tlb1ps;
+
+ tlb0cfg = mfspr(SPRN_TLB0CFG);
+ tlb1cfg = mfspr(SPRN_TLB1CFG);
+ tlb1ps = mfspr(SPRN_TLB1PS);
+ eptcfg = mfspr(SPRN_EPTCFG);
+
+ if ((tlb1cfg & TLBnCFG_IND) && (tlb0cfg & TLBnCFG_PT))
+ book3e_htw_mode = PPC_HTW_E6500;
+
+ /*
+ * We expect 4K subpage size and unrestricted indirect size.
+ * The lack of a restriction on indirect size is a Freescale
+ * extension, indicated by PSn = 0 but SPSn != 0.
+ */
+ if (eptcfg != 2)
+ book3e_htw_mode = PPC_HTW_NONE;
+
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+
+ if (tlb1ps & (1U << (def->shift - 10))) {
+ def->flags |= MMU_PAGE_SIZE_DIRECT;
+
+ if (book3e_htw_mode && psize == MMU_PAGE_2M)
+ def->flags |= MMU_PAGE_SIZE_INDIRECT;
+ }
+ }
+
+ goto out;
+ }
+#endif
+
+ tlb0cfg = mfspr(SPRN_TLB0CFG);
+ tlb0ps = mfspr(SPRN_TLB0PS);
+ eptcfg = mfspr(SPRN_EPTCFG);
+
+ /* Look for supported direct sizes */
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+
+ if (tlb0ps & (1U << (def->shift - 10)))
+ def->flags |= MMU_PAGE_SIZE_DIRECT;
+ }
+
+ /* Indirect page sizes supported ? */
+ if ((tlb0cfg & TLBnCFG_IND) == 0 ||
+ (tlb0cfg & TLBnCFG_PT) == 0)
+ goto out;
+
+ book3e_htw_mode = PPC_HTW_IBM;
+
+ /* Now, we only deal with one IND page size for each
+ * direct size. Hopefully all implementations today are
+ * unambiguous, but we might want to be careful in the
+ * future.
+ */
+ for (i = 0; i < 3; i++) {
+ unsigned int ps, sps;
+
+ sps = eptcfg & 0x1f;
+ eptcfg >>= 5;
+ ps = eptcfg & 0x1f;
+ eptcfg >>= 5;
+ if (!ps || !sps)
+ continue;
+ for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+
+ if (ps == (def->shift - 10))
+ def->flags |= MMU_PAGE_SIZE_INDIRECT;
+ if (sps == (def->shift - 10))
+ def->ind = ps + 10;
+ }
+ }
+
+out:
+ /* Cleanup array and print summary */
+ pr_info("MMU: Supported page sizes\n");
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ struct mmu_psize_def *def = &mmu_psize_defs[psize];
+ const char *__page_type_names[] = {
+ "unsupported",
+ "direct",
+ "indirect",
+ "direct & indirect"
+ };
+ if (def->flags == 0) {
+ def->shift = 0;
+ continue;
+ }
+ pr_info(" %8ld KB as %s\n", 1ul << (def->shift - 10),
+ __page_type_names[def->flags & 0x3]);
+ }
+}
+
+static void setup_mmu_htw(void)
+{
+ /*
+ * If we want to use HW tablewalk, enable it by patching the TLB miss
+ * handlers to branch to the one dedicated to it.
+ */
+
+ switch (book3e_htw_mode) {
+ case PPC_HTW_IBM:
+ patch_exception(0x1c0, exc_data_tlb_miss_htw_book3e);
+ patch_exception(0x1e0, exc_instruction_tlb_miss_htw_book3e);
+ break;
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ case PPC_HTW_E6500:
+ extlb_level_exc = EX_TLB_SIZE;
+ patch_exception(0x1c0, exc_data_tlb_miss_e6500_book3e);
+ patch_exception(0x1e0, exc_instruction_tlb_miss_e6500_book3e);
+ break;
+#endif
+ }
+ pr_info("MMU: Book3E HW tablewalk %s\n",
+ book3e_htw_mode != PPC_HTW_NONE ? "enabled" : "not supported");
+}
+
+/*
+ * Early initialization of the MMU TLB code
+ */
+static void early_init_this_mmu(void)
+{
+ unsigned int mas4;
+
+ /* Set MAS4 based on page table setting */
+
+ mas4 = 0x4 << MAS4_WIMGED_SHIFT;
+ switch (book3e_htw_mode) {
+ case PPC_HTW_E6500:
+ mas4 |= MAS4_INDD;
+ mas4 |= BOOK3E_PAGESZ_2M << MAS4_TSIZED_SHIFT;
+ mas4 |= MAS4_TLBSELD(1);
+ mmu_pte_psize = MMU_PAGE_2M;
+ break;
+
+ case PPC_HTW_IBM:
+ mas4 |= MAS4_INDD;
+#ifdef CONFIG_PPC_64K_PAGES
+ mas4 |= BOOK3E_PAGESZ_256M << MAS4_TSIZED_SHIFT;
+ mmu_pte_psize = MMU_PAGE_256M;
+#else
+ mas4 |= BOOK3E_PAGESZ_1M << MAS4_TSIZED_SHIFT;
+ mmu_pte_psize = MMU_PAGE_1M;
+#endif
+ break;
+
+ case PPC_HTW_NONE:
+#ifdef CONFIG_PPC_64K_PAGES
+ mas4 |= BOOK3E_PAGESZ_64K << MAS4_TSIZED_SHIFT;
+#else
+ mas4 |= BOOK3E_PAGESZ_4K << MAS4_TSIZED_SHIFT;
+#endif
+ mmu_pte_psize = mmu_virtual_psize;
+ break;
+ }
+ mtspr(SPRN_MAS4, mas4);
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
+ unsigned int num_cams;
+
+ /* use a quarter of the TLBCAM for bolted linear map */
+ num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;
+ linear_map_top = map_mem_in_cams(linear_map_top, num_cams);
+ }
+#endif
+
+ /* A sync won't hurt us after mucking around with
+ * the MMU configuration
+ */
+ mb();
+}
+
+static void __init early_init_mmu_global(void)
+{
+ /* XXX This will have to be decided at runtime, but right
+ * now our boot and TLB miss code hard wires it. Ideally
+ * we should find out a suitable page size and patch the
+ * TLB miss code (either that or use the PACA to store
+ * the value we want)
+ */
+ mmu_linear_psize = MMU_PAGE_1G;
+
+ /* XXX This should be decided at runtime based on supported
+ * page sizes in the TLB, but for now let's assume 16M is
+ * always there and a good fit (which it probably is)
+ *
+ * Freescale booke only supports 4K pages in TLB0, so use that.
+ */
+ if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
+ mmu_vmemmap_psize = MMU_PAGE_4K;
+ else
+ mmu_vmemmap_psize = MMU_PAGE_16M;
+
+ /* XXX This code only checks for TLB 0 capabilities and doesn't
+ * check what page size combos are supported by the HW. It
+ * also doesn't handle the case where a separate array holds
+ * the IND entries from the array loaded by the PT.
+ */
+ /* Look for supported page sizes */
+ setup_page_sizes();
+
+ /* Look for HW tablewalk support */
+ setup_mmu_htw();
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
+ if (book3e_htw_mode == PPC_HTW_NONE) {
+ extlb_level_exc = EX_TLB_SIZE;
+ patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
+ patch_exception(0x1e0,
+ exc_instruction_tlb_miss_bolted_book3e);
+ }
+ }
+#endif
+
+ /* Set the global containing the top of the linear mapping
+ * for use by the TLB miss code
+ */
+ linear_map_top = memblock_end_of_DRAM();
+}
+
+static void __init early_mmu_set_memory_limit(void)
+{
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
+ /*
+ * Limit memory so we dont have linear faults.
+ * Unlike memblock_set_current_limit, which limits
+ * memory available during early boot, this permanently
+ * reduces the memory available to Linux. We need to
+ * do this because highmem is not supported on 64-bit.
+ */
+ memblock_enforce_memory_limit(linear_map_top);
+ }
+#endif
+
+ memblock_set_current_limit(linear_map_top);
+}
+
+/* boot cpu only */
+void __init early_init_mmu(void)
+{
+ early_init_mmu_global();
+ early_init_this_mmu();
+ early_mmu_set_memory_limit();
+}
+
+void early_init_mmu_secondary(void)
+{
+ early_init_this_mmu();
+}
+
+void setup_initial_memory_limit(phys_addr_t first_memblock_base,
+ phys_addr_t first_memblock_size)
+{
+ /* On non-FSL Embedded 64-bit, we adjust the RMA size to match
+ * the bolted TLB entry. We know for now that only 1G
+ * entries are supported though that may eventually
+ * change.
+ *
+ * on FSL Embedded 64-bit, we adjust the RMA size to match the
+ * first bolted TLB entry size. We still limit max to 1G even if
+ * the TLB could cover more. This is due to what the early init
+ * code is setup to do.
+ *
+ * We crop it to the size of the first MEMBLOCK to
+ * avoid going over total available memory just in case...
+ */
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {
+ unsigned long linear_sz;
+ linear_sz = calc_cam_sz(first_memblock_size, PAGE_OFFSET,
+ first_memblock_base);
+ ppc64_rma_size = min_t(u64, linear_sz, 0x40000000);
+ } else
+#endif
+ ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000);
+
+ /* Finally limit subsequent allocations */
+ memblock_set_current_limit(first_memblock_base + ppc64_rma_size);
+}
+#else /* ! CONFIG_PPC64 */
+void __init early_init_mmu(void)
+{
+#ifdef CONFIG_PPC_47x
+ early_init_mmu_47x();
+#endif
+}
+#endif /* CONFIG_PPC64 */