Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 776 insertions, 0 deletions

diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
new file mode 100644
index 000000000..ca4a302d4
--- /dev/null
+++ b/arch/parisc/kernel/cache.c
@@ -0,0 +1,776 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1999-2006 Helge Deller <deller@gmx.de> (07-13-1999)
+ * Copyright (C) 1999 SuSE GmbH Nuernberg
+ * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
+ *
+ * Cache and TLB management
+ *
+ */
+ 
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <asm/pdc.h>
+#include <asm/cache.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <asm/sections.h>
+#include <asm/shmparam.h>
+#include <asm/mmu_context.h>
+
+int split_tlb __ro_after_init;
+int dcache_stride __ro_after_init;
+int icache_stride __ro_after_init;
+EXPORT_SYMBOL(dcache_stride);
+
+void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
+EXPORT_SYMBOL(flush_dcache_page_asm);
+void purge_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
+void flush_icache_page_asm(unsigned long phys_addr, unsigned long vaddr);
+
+/* Internal implementation in arch/parisc/kernel/pacache.S */
+void flush_data_cache_local(void *);  /* flushes local data-cache only */
+void flush_instruction_cache_local(void); /* flushes local code-cache only */
+
+/* On some machines (i.e., ones with the Merced bus), there can be
+ * only a single PxTLB broadcast at a time; this must be guaranteed
+ * by software. We need a spinlock around all TLB flushes to ensure
+ * this.
+ */
+DEFINE_SPINLOCK(pa_tlb_flush_lock);
+
+#if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
+int pa_serialize_tlb_flushes __ro_after_init;
+#endif
+
+struct pdc_cache_info cache_info __ro_after_init;
+#ifndef CONFIG_PA20
+static struct pdc_btlb_info btlb_info __ro_after_init;
+#endif
+
+DEFINE_STATIC_KEY_TRUE(parisc_has_cache);
+DEFINE_STATIC_KEY_TRUE(parisc_has_dcache);
+DEFINE_STATIC_KEY_TRUE(parisc_has_icache);
+
+static void cache_flush_local_cpu(void *dummy)
+{
+	if (static_branch_likely(&parisc_has_icache))
+		flush_instruction_cache_local();
+	if (static_branch_likely(&parisc_has_dcache))
+		flush_data_cache_local(NULL);
+}
+
+void flush_cache_all_local(void)
+{
+	cache_flush_local_cpu(NULL);
+}
+
+void flush_cache_all(void)
+{
+	if (static_branch_likely(&parisc_has_cache))
+		on_each_cpu(cache_flush_local_cpu, NULL, 1);
+}
+
+static inline void flush_data_cache(void)
+{
+	if (static_branch_likely(&parisc_has_dcache))
+		on_each_cpu(flush_data_cache_local, NULL, 1);
+}
+
+
+/* Kernel virtual address of pfn.  */
+#define pfn_va(pfn)	__va(PFN_PHYS(pfn))
+
+void
+__update_cache(pte_t pte)
+{
+	unsigned long pfn = pte_pfn(pte);
+	struct page *page;
+
+	/* We don't have pte special.  As a result, we can be called with
+	   an invalid pfn and we don't need to flush the kernel dcache page.
+	   This occurs with FireGL card in C8000.  */
+	if (!pfn_valid(pfn))
+		return;
+
+	page = pfn_to_page(pfn);
+	if (page_mapping_file(page) &&
+	    test_bit(PG_dcache_dirty, &page->flags)) {
+		flush_kernel_dcache_page_addr(pfn_va(pfn));
+		clear_bit(PG_dcache_dirty, &page->flags);
+	} else if (parisc_requires_coherency())
+		flush_kernel_dcache_page_addr(pfn_va(pfn));
+}
+
+void
+show_cache_info(struct seq_file *m)
+{
+	char buf[32];
+
+	seq_printf(m, "I-cache\t\t: %ld KB\n", 
+		cache_info.ic_size/1024 );
+	if (cache_info.dc_loop != 1)
+		snprintf(buf, 32, "%lu-way associative", cache_info.dc_loop);
+	seq_printf(m, "D-cache\t\t: %ld KB (%s%s, %s, alias=%d)\n",
+		cache_info.dc_size/1024,
+		(cache_info.dc_conf.cc_wt ? "WT":"WB"),
+		(cache_info.dc_conf.cc_sh ? ", shared I/D":""),
+		((cache_info.dc_loop == 1) ? "direct mapped" : buf),
+		cache_info.dc_conf.cc_alias
+	);
+	seq_printf(m, "ITLB entries\t: %ld\n" "DTLB entries\t: %ld%s\n",
+		cache_info.it_size,
+		cache_info.dt_size,
+		cache_info.dt_conf.tc_sh ? " - shared with ITLB":""
+	);
+		
+#ifndef CONFIG_PA20
+	/* BTLB - Block TLB */
+	if (btlb_info.max_size==0) {
+		seq_printf(m, "BTLB\t\t: not supported\n" );
+	} else {
+		seq_printf(m, 
+		"BTLB fixed\t: max. %d pages, pagesize=%d (%dMB)\n"
+		"BTLB fix-entr.\t: %d instruction, %d data (%d combined)\n"
+		"BTLB var-entr.\t: %d instruction, %d data (%d combined)\n",
+		btlb_info.max_size, (int)4096,
+		btlb_info.max_size>>8,
+		btlb_info.fixed_range_info.num_i,
+		btlb_info.fixed_range_info.num_d,
+		btlb_info.fixed_range_info.num_comb, 
+		btlb_info.variable_range_info.num_i,
+		btlb_info.variable_range_info.num_d,
+		btlb_info.variable_range_info.num_comb
+		);
+	}
+#endif
+}
+
+void __init 
+parisc_cache_init(void)
+{
+	if (pdc_cache_info(&cache_info) < 0)
+		panic("parisc_cache_init: pdc_cache_info failed");
+
+#if 0
+	printk("ic_size %lx dc_size %lx it_size %lx\n",
+		cache_info.ic_size,
+		cache_info.dc_size,
+		cache_info.it_size);
+
+	printk("DC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
+		cache_info.dc_base,
+		cache_info.dc_stride,
+		cache_info.dc_count,
+		cache_info.dc_loop);
+
+	printk("dc_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
+		*(unsigned long *) (&cache_info.dc_conf),
+		cache_info.dc_conf.cc_alias,
+		cache_info.dc_conf.cc_block,
+		cache_info.dc_conf.cc_line,
+		cache_info.dc_conf.cc_shift);
+	printk("	wt %d sh %d cst %d hv %d\n",
+		cache_info.dc_conf.cc_wt,
+		cache_info.dc_conf.cc_sh,
+		cache_info.dc_conf.cc_cst,
+		cache_info.dc_conf.cc_hv);
+
+	printk("IC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
+		cache_info.ic_base,
+		cache_info.ic_stride,
+		cache_info.ic_count,
+		cache_info.ic_loop);
+
+	printk("IT  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx off_base 0x%lx off_stride 0x%lx off_count 0x%lx\n",
+		cache_info.it_sp_base,
+		cache_info.it_sp_stride,
+		cache_info.it_sp_count,
+		cache_info.it_loop,
+		cache_info.it_off_base,
+		cache_info.it_off_stride,
+		cache_info.it_off_count);
+
+	printk("DT  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx off_base 0x%lx off_stride 0x%lx off_count 0x%lx\n",
+		cache_info.dt_sp_base,
+		cache_info.dt_sp_stride,
+		cache_info.dt_sp_count,
+		cache_info.dt_loop,
+		cache_info.dt_off_base,
+		cache_info.dt_off_stride,
+		cache_info.dt_off_count);
+
+	printk("ic_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
+		*(unsigned long *) (&cache_info.ic_conf),
+		cache_info.ic_conf.cc_alias,
+		cache_info.ic_conf.cc_block,
+		cache_info.ic_conf.cc_line,
+		cache_info.ic_conf.cc_shift);
+	printk("	wt %d sh %d cst %d hv %d\n",
+		cache_info.ic_conf.cc_wt,
+		cache_info.ic_conf.cc_sh,
+		cache_info.ic_conf.cc_cst,
+		cache_info.ic_conf.cc_hv);
+
+	printk("D-TLB conf: sh %d page %d cst %d aid %d sr %d\n",
+		cache_info.dt_conf.tc_sh,
+		cache_info.dt_conf.tc_page,
+		cache_info.dt_conf.tc_cst,
+		cache_info.dt_conf.tc_aid,
+		cache_info.dt_conf.tc_sr);
+
+	printk("I-TLB conf: sh %d page %d cst %d aid %d sr %d\n",
+		cache_info.it_conf.tc_sh,
+		cache_info.it_conf.tc_page,
+		cache_info.it_conf.tc_cst,
+		cache_info.it_conf.tc_aid,
+		cache_info.it_conf.tc_sr);
+#endif
+
+	split_tlb = 0;
+	if (cache_info.dt_conf.tc_sh == 0 || cache_info.dt_conf.tc_sh == 2) {
+		if (cache_info.dt_conf.tc_sh == 2)
+			printk(KERN_WARNING "Unexpected TLB configuration. "
+			"Will flush I/D separately (could be optimized).\n");
+
+		split_tlb = 1;
+	}
+
+	/* "New and Improved" version from Jim Hull 
+	 *	(1 << (cc_block-1)) * (cc_line << (4 + cnf.cc_shift))
+	 * The following CAFL_STRIDE is an optimized version, see
+	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023625.html
+	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023671.html
+	 */
+#define CAFL_STRIDE(cnf) (cnf.cc_line << (3 + cnf.cc_block + cnf.cc_shift))
+	dcache_stride = CAFL_STRIDE(cache_info.dc_conf);
+	icache_stride = CAFL_STRIDE(cache_info.ic_conf);
+#undef CAFL_STRIDE
+
+#ifndef CONFIG_PA20
+	if (pdc_btlb_info(&btlb_info) < 0) {
+		memset(&btlb_info, 0, sizeof btlb_info);
+	}
+#endif
+
+	if ((boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) ==
+						PDC_MODEL_NVA_UNSUPPORTED) {
+		printk(KERN_WARNING "parisc_cache_init: Only equivalent aliasing supported!\n");
+#if 0
+		panic("SMP kernel required to avoid non-equivalent aliasing");
+#endif
+	}
+}
+
+void disable_sr_hashing(void)
+{
+	int srhash_type, retval;
+	unsigned long space_bits;
+
+	switch (boot_cpu_data.cpu_type) {
+	case pcx: /* We shouldn't get this far.  setup.c should prevent it. */
+		BUG();
+		return;
+
+	case pcxs:
+	case pcxt:
+	case pcxt_:
+		srhash_type = SRHASH_PCXST;
+		break;
+
+	case pcxl:
+		srhash_type = SRHASH_PCXL;
+		break;
+
+	case pcxl2: /* pcxl2 doesn't support space register hashing */
+		return;
+
+	default: /* Currently all PA2.0 machines use the same ins. sequence */
+		srhash_type = SRHASH_PA20;
+		break;
+	}
+
+	disable_sr_hashing_asm(srhash_type);
+
+	retval = pdc_spaceid_bits(&space_bits);
+	/* If this procedure isn't implemented, don't panic. */
+	if (retval < 0 && retval != PDC_BAD_OPTION)
+		panic("pdc_spaceid_bits call failed.\n");
+	if (space_bits != 0)
+		panic("SpaceID hashing is still on!\n");
+}
+
+static inline void
+__flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
+		   unsigned long physaddr)
+{
+	if (!static_branch_likely(&parisc_has_cache))
+		return;
+	preempt_disable();
+	flush_dcache_page_asm(physaddr, vmaddr);
+	if (vma->vm_flags & VM_EXEC)
+		flush_icache_page_asm(physaddr, vmaddr);
+	preempt_enable();
+}
+
+static void flush_user_cache_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+	unsigned long flags, space, pgd, prot;
+#ifdef CONFIG_TLB_PTLOCK
+	unsigned long pgd_lock;
+#endif
+
+	vmaddr &= PAGE_MASK;
+
+	preempt_disable();
+
+	/* Set context for flush */
+	local_irq_save(flags);
+	prot = mfctl(8);
+	space = mfsp(SR_USER);
+	pgd = mfctl(25);
+#ifdef CONFIG_TLB_PTLOCK
+	pgd_lock = mfctl(28);
+#endif
+	switch_mm_irqs_off(NULL, vma->vm_mm, NULL);
+	local_irq_restore(flags);
+
+	flush_user_dcache_range_asm(vmaddr, vmaddr + PAGE_SIZE);
+	if (vma->vm_flags & VM_EXEC)
+		flush_user_icache_range_asm(vmaddr, vmaddr + PAGE_SIZE);
+	flush_tlb_page(vma, vmaddr);
+
+	/* Restore previous context */
+	local_irq_save(flags);
+#ifdef CONFIG_TLB_PTLOCK
+	mtctl(pgd_lock, 28);
+#endif
+	mtctl(pgd, 25);
+	mtsp(space, SR_USER);
+	mtctl(prot, 8);
+	local_irq_restore(flags);
+
+	preempt_enable();
+}
+
+static inline pte_t *get_ptep(struct mm_struct *mm, unsigned long addr)
+{
+	pte_t *ptep = NULL;
+	pgd_t *pgd = mm->pgd;
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	if (!pgd_none(*pgd)) {
+		p4d = p4d_offset(pgd, addr);
+		if (!p4d_none(*p4d)) {
+			pud = pud_offset(p4d, addr);
+			if (!pud_none(*pud)) {
+				pmd = pmd_offset(pud, addr);
+				if (!pmd_none(*pmd))
+					ptep = pte_offset_map(pmd, addr);
+			}
+		}
+	}
+	return ptep;
+}
+
+static inline bool pte_needs_flush(pte_t pte)
+{
+	return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_NO_CACHE))
+		== (_PAGE_PRESENT | _PAGE_ACCESSED);
+}
+
+void flush_dcache_page(struct page *page)
+{
+	struct address_space *mapping = page_mapping_file(page);
+	struct vm_area_struct *mpnt;
+	unsigned long offset;
+	unsigned long addr, old_addr = 0;
+	unsigned long count = 0;
+	unsigned long flags;
+	pgoff_t pgoff;
+
+	if (mapping && !mapping_mapped(mapping)) {
+		set_bit(PG_dcache_dirty, &page->flags);
+		return;
+	}
+
+	flush_kernel_dcache_page_addr(page_address(page));
+
+	if (!mapping)
+		return;
+
+	pgoff = page->index;
+
+	/*
+	 * We have carefully arranged in arch_get_unmapped_area() that
+	 * *any* mappings of a file are always congruently mapped (whether
+	 * declared as MAP_PRIVATE or MAP_SHARED), so we only need
+	 * to flush one address here for them all to become coherent
+	 * on machines that support equivalent aliasing
+	 */
+	flush_dcache_mmap_lock_irqsave(mapping, flags);
+	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
+		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+		addr = mpnt->vm_start + offset;
+		if (parisc_requires_coherency()) {
+			pte_t *ptep;
+
+			ptep = get_ptep(mpnt->vm_mm, addr);
+			if (ptep && pte_needs_flush(*ptep))
+				flush_user_cache_page(mpnt, addr);
+		} else {
+			/*
+			 * The TLB is the engine of coherence on parisc:
+			 * The CPU is entitled to speculate any page
+			 * with a TLB mapping, so here we kill the
+			 * mapping then flush the page along a special
+			 * flush only alias mapping. This guarantees that
+			 * the page is no-longer in the cache for any
+			 * process and nor may it be speculatively read
+			 * in (until the user or kernel specifically
+			 * accesses it, of course)
+			 */
+			flush_tlb_page(mpnt, addr);
+			if (old_addr == 0 || (old_addr & (SHM_COLOUR - 1))
+					!= (addr & (SHM_COLOUR - 1))) {
+				__flush_cache_page(mpnt, addr, page_to_phys(page));
+				/*
+				 * Software is allowed to have any number
+				 * of private mappings to a page.
+				 */
+				if (!(mpnt->vm_flags & VM_SHARED))
+					continue;
+				if (old_addr)
+					pr_err("INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %pD\n",
+						old_addr, addr, mpnt->vm_file);
+				old_addr = addr;
+			}
+		}
+		WARN_ON(++count == 4096);
+	}
+	flush_dcache_mmap_unlock_irqrestore(mapping, flags);
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+/* Defined in arch/parisc/kernel/pacache.S */
+EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
+EXPORT_SYMBOL(flush_kernel_icache_range_asm);
+
+#define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
+static unsigned long parisc_cache_flush_threshold __ro_after_init = FLUSH_THRESHOLD;
+
+#define FLUSH_TLB_THRESHOLD (16*1024) /* 16 KiB minimum TLB threshold */
+static unsigned long parisc_tlb_flush_threshold __ro_after_init = ~0UL;
+
+void __init parisc_setup_cache_timing(void)
+{
+	unsigned long rangetime, alltime;
+	unsigned long size;
+	unsigned long threshold, threshold2;
+
+	alltime = mfctl(16);
+	flush_data_cache();
+	alltime = mfctl(16) - alltime;
+
+	size = (unsigned long)(_end - _text);
+	rangetime = mfctl(16);
+	flush_kernel_dcache_range((unsigned long)_text, size);
+	rangetime = mfctl(16) - rangetime;
+
+	printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
+		alltime, size, rangetime);
+
+	threshold = L1_CACHE_ALIGN((unsigned long)((uint64_t)size * alltime / rangetime));
+	pr_info("Calculated flush threshold is %lu KiB\n",
+		threshold/1024);
+
+	/*
+	 * The threshold computed above isn't very reliable. The following
+	 * heuristic works reasonably well on c8000/rp3440.
+	 */
+	threshold2 = cache_info.dc_size * num_online_cpus();
+	parisc_cache_flush_threshold = threshold2;
+	printk(KERN_INFO "Cache flush threshold set to %lu KiB\n",
+		parisc_cache_flush_threshold/1024);
+
+	/* calculate TLB flush threshold */
+
+	/* On SMP machines, skip the TLB measure of kernel text which
+	 * has been mapped as huge pages. */
+	if (num_online_cpus() > 1 && !parisc_requires_coherency()) {
+		threshold = max(cache_info.it_size, cache_info.dt_size);
+		threshold *= PAGE_SIZE;
+		threshold /= num_online_cpus();
+		goto set_tlb_threshold;
+	}
+
+	size = (unsigned long)_end - (unsigned long)_text;
+	rangetime = mfctl(16);
+	flush_tlb_kernel_range((unsigned long)_text, (unsigned long)_end);
+	rangetime = mfctl(16) - rangetime;
+
+	alltime = mfctl(16);
+	flush_tlb_all();
+	alltime = mfctl(16) - alltime;
+
+	printk(KERN_INFO "Whole TLB flush %lu cycles, Range flush %lu bytes %lu cycles\n",
+		alltime, size, rangetime);
+
+	threshold = PAGE_ALIGN((num_online_cpus() * size * alltime) / rangetime);
+	printk(KERN_INFO "Calculated TLB flush threshold %lu KiB\n",
+		threshold/1024);
+
+set_tlb_threshold:
+	if (threshold > FLUSH_TLB_THRESHOLD)
+		parisc_tlb_flush_threshold = threshold;
+	else
+		parisc_tlb_flush_threshold = FLUSH_TLB_THRESHOLD;
+
+	printk(KERN_INFO "TLB flush threshold set to %lu KiB\n",
+		parisc_tlb_flush_threshold/1024);
+}
+
+extern void purge_kernel_dcache_page_asm(unsigned long);
+extern void clear_user_page_asm(void *, unsigned long);
+extern void copy_user_page_asm(void *, void *, unsigned long);
+
+void flush_kernel_dcache_page_addr(const void *addr)
+{
+	unsigned long flags;
+
+	flush_kernel_dcache_page_asm(addr);
+	purge_tlb_start(flags);
+	pdtlb(SR_KERNEL, addr);
+	purge_tlb_end(flags);
+}
+EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
+
+static void flush_cache_page_if_present(struct vm_area_struct *vma,
+	unsigned long vmaddr, unsigned long pfn)
+{
+	pte_t *ptep = get_ptep(vma->vm_mm, vmaddr);
+
+	/*
+	 * The pte check is racy and sometimes the flush will trigger
+	 * a non-access TLB miss. Hopefully, the page has already been
+	 * flushed.
+	 */
+	if (ptep && pte_needs_flush(*ptep))
+		flush_cache_page(vma, vmaddr, pfn);
+}
+
+void copy_user_highpage(struct page *to, struct page *from,
+	unsigned long vaddr, struct vm_area_struct *vma)
+{
+	void *kto, *kfrom;
+
+	kfrom = kmap_local_page(from);
+	kto = kmap_local_page(to);
+	flush_cache_page_if_present(vma, vaddr, page_to_pfn(from));
+	copy_page_asm(kto, kfrom);
+	kunmap_local(kto);
+	kunmap_local(kfrom);
+}
+
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+		unsigned long user_vaddr, void *dst, void *src, int len)
+{
+	flush_cache_page_if_present(vma, user_vaddr, page_to_pfn(page));
+	memcpy(dst, src, len);
+	flush_kernel_dcache_range_asm((unsigned long)dst, (unsigned long)dst + len);
+}
+
+void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+		unsigned long user_vaddr, void *dst, void *src, int len)
+{
+	flush_cache_page_if_present(vma, user_vaddr, page_to_pfn(page));
+	memcpy(dst, src, len);
+}
+
+/* __flush_tlb_range()
+ *
+ * returns 1 if all TLBs were flushed.
+ */
+int __flush_tlb_range(unsigned long sid, unsigned long start,
+		      unsigned long end)
+{
+	unsigned long flags;
+
+	if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
+	    end - start >= parisc_tlb_flush_threshold) {
+		flush_tlb_all();
+		return 1;
+	}
+
+	/* Purge TLB entries for small ranges using the pdtlb and
+	   pitlb instructions.  These instructions execute locally
+	   but cause a purge request to be broadcast to other TLBs.  */
+	while (start < end) {
+		purge_tlb_start(flags);
+		mtsp(sid, SR_TEMP1);
+		pdtlb(SR_TEMP1, start);
+		pitlb(SR_TEMP1, start);
+		purge_tlb_end(flags);
+		start += PAGE_SIZE;
+	}
+	return 0;
+}
+
+static void flush_cache_pages(struct vm_area_struct *vma, unsigned long start, unsigned long end)
+{
+	unsigned long addr, pfn;
+	pte_t *ptep;
+
+	for (addr = start; addr < end; addr += PAGE_SIZE) {
+		/*
+		 * The vma can contain pages that aren't present. Although
+		 * the pte search is expensive, we need the pte to find the
+		 * page pfn and to check whether the page should be flushed.
+		 */
+		ptep = get_ptep(vma->vm_mm, addr);
+		if (ptep && pte_needs_flush(*ptep)) {
+			if (parisc_requires_coherency()) {
+				flush_user_cache_page(vma, addr);
+			} else {
+				pfn = pte_pfn(*ptep);
+				if (WARN_ON(!pfn_valid(pfn)))
+					return;
+				__flush_cache_page(vma, addr, PFN_PHYS(pfn));
+			}
+		}
+	}
+}
+
+static inline unsigned long mm_total_size(struct mm_struct *mm)
+{
+	struct vm_area_struct *vma;
+	unsigned long usize = 0;
+	VMA_ITERATOR(vmi, mm, 0);
+
+	for_each_vma(vmi, vma) {
+		if (usize >= parisc_cache_flush_threshold)
+			break;
+		usize += vma->vm_end - vma->vm_start;
+	}
+	return usize;
+}
+
+void flush_cache_mm(struct mm_struct *mm)
+{
+	struct vm_area_struct *vma;
+	VMA_ITERATOR(vmi, mm, 0);
+
+	/*
+	 * Flushing the whole cache on each cpu takes forever on
+	 * rp3440, etc. So, avoid it if the mm isn't too big.
+	 *
+	 * Note that we must flush the entire cache on machines
+	 * with aliasing caches to prevent random segmentation
+	 * faults.
+	 */
+	if (!parisc_requires_coherency()
+	    ||  mm_total_size(mm) >= parisc_cache_flush_threshold) {
+		if (WARN_ON(IS_ENABLED(CONFIG_SMP) && arch_irqs_disabled()))
+			return;
+		flush_tlb_all();
+		flush_cache_all();
+		return;
+	}
+
+	/* Flush mm */
+	for_each_vma(vmi, vma)
+		flush_cache_pages(vma, vma->vm_start, vma->vm_end);
+}
+
+void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
+{
+	if (!parisc_requires_coherency()
+	    || end - start >= parisc_cache_flush_threshold) {
+		if (WARN_ON(IS_ENABLED(CONFIG_SMP) && arch_irqs_disabled()))
+			return;
+		flush_tlb_range(vma, start, end);
+		flush_cache_all();
+		return;
+	}
+
+	flush_cache_pages(vma, start, end);
+}
+
+void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
+{
+	if (WARN_ON(!pfn_valid(pfn)))
+		return;
+	if (parisc_requires_coherency())
+		flush_user_cache_page(vma, vmaddr);
+	else
+		__flush_cache_page(vma, vmaddr, PFN_PHYS(pfn));
+}
+
+void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
+{
+	if (!PageAnon(page))
+		return;
+
+	if (parisc_requires_coherency()) {
+		if (vma->vm_flags & VM_SHARED)
+			flush_data_cache();
+		else
+			flush_user_cache_page(vma, vmaddr);
+		return;
+	}
+
+	flush_tlb_page(vma, vmaddr);
+	preempt_disable();
+	flush_dcache_page_asm(page_to_phys(page), vmaddr);
+	preempt_enable();
+}
+
+void flush_kernel_vmap_range(void *vaddr, int size)
+{
+	unsigned long start = (unsigned long)vaddr;
+	unsigned long end = start + size;
+
+	if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
+	    (unsigned long)size >= parisc_cache_flush_threshold) {
+		flush_tlb_kernel_range(start, end);
+		flush_data_cache();
+		return;
+	}
+
+	flush_kernel_dcache_range_asm(start, end);
+	flush_tlb_kernel_range(start, end);
+}
+EXPORT_SYMBOL(flush_kernel_vmap_range);
+
+void invalidate_kernel_vmap_range(void *vaddr, int size)
+{
+	unsigned long start = (unsigned long)vaddr;
+	unsigned long end = start + size;
+
+	/* Ensure DMA is complete */
+	asm_syncdma();
+
+	if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
+	    (unsigned long)size >= parisc_cache_flush_threshold) {
+		flush_tlb_kernel_range(start, end);
+		flush_data_cache();
+		return;
+	}
+
+	purge_kernel_dcache_range_asm(start, end);
+	flush_tlb_kernel_range(start, end);
+}
+EXPORT_SYMBOL(invalidate_kernel_vmap_range);