swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: f443e374ae131c168a065ea1748feac6b2e76613 authored by Linus Torvalds on 20 March 2022, 20:14:17 UTC
Linux 5.17
Linux 5.17
Tip revision: f443e37
cache.c
/*
* 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>
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);
/* 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);
/* Swapper page setup lock. */
DEFINE_SPINLOCK(pa_swapper_pg_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
#ifdef CONFIG_SMP
void
flush_data_cache(void)
{
on_each_cpu(flush_data_cache_local, NULL, 1);
}
void
flush_instruction_cache(void)
{
on_each_cpu(flush_instruction_cache_local, NULL, 1);
}
#endif
void
flush_cache_all_local(void)
{
flush_instruction_cache_local(NULL);
flush_data_cache_local(NULL);
}
EXPORT_SYMBOL(flush_cache_all_local);
/* 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)\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));
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 __init 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)
{
preempt_disable();
flush_dcache_page_asm(physaddr, vmaddr);
if (vma->vm_flags & VM_EXEC)
flush_icache_page_asm(physaddr, vmaddr);
preempt_enable();
}
static inline void
__purge_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
unsigned long physaddr)
{
preempt_disable();
purge_dcache_page_asm(physaddr, vmaddr);
if (vma->vm_flags & VM_EXEC)
flush_icache_page_asm(physaddr, vmaddr);
preempt_enable();
}
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;
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 */
flush_dcache_mmap_lock(mapping);
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
addr = mpnt->vm_start + offset;
/* 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));
if (parisc_requires_coherency() && old_addr)
printk(KERN_ERR "INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %pD\n", old_addr, addr, mpnt->vm_file);
old_addr = addr;
}
}
flush_dcache_mmap_unlock(mapping);
}
EXPORT_SYMBOL(flush_dcache_page);
/* Defined in arch/parisc/kernel/pacache.S */
EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
EXPORT_SYMBOL(flush_data_cache_local);
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;
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(size * alltime / rangetime);
if (threshold > cache_info.dc_size)
threshold = cache_info.dc_size;
if (threshold)
parisc_cache_flush_threshold = threshold;
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(void *addr)
{
unsigned long flags;
flush_kernel_dcache_page_asm(addr);
purge_tlb_start(flags);
pdtlb_kernel(addr);
purge_tlb_end(flags);
}
EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
struct page *pg)
{
/* Copy using kernel mapping. No coherency is needed (all in
kunmap) for the `to' page. However, the `from' page needs to
be flushed through a mapping equivalent to the user mapping
before it can be accessed through the kernel mapping. */
preempt_disable();
flush_dcache_page_asm(__pa(vfrom), vaddr);
copy_page_asm(vto, vfrom);
preempt_enable();
}
EXPORT_SYMBOL(copy_user_page);
/* __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, 1);
pdtlb(start);
pitlb(start);
purge_tlb_end(flags);
start += PAGE_SIZE;
}
return 0;
}
static void cacheflush_h_tmp_function(void *dummy)
{
flush_cache_all_local();
}
void flush_cache_all(void)
{
on_each_cpu(cacheflush_h_tmp_function, NULL, 1);
}
static inline unsigned long mm_total_size(struct mm_struct *mm)
{
struct vm_area_struct *vma;
unsigned long usize = 0;
for (vma = mm->mmap; vma; vma = vma->vm_next)
usize += vma->vm_end - vma->vm_start;
return usize;
}
static inline pte_t *get_ptep(pgd_t *pgd, unsigned long addr)
{
pte_t *ptep = NULL;
if (!pgd_none(*pgd)) {
p4d_t *p4d = p4d_offset(pgd, addr);
if (!p4d_none(*p4d)) {
pud_t *pud = pud_offset(p4d, addr);
if (!pud_none(*pud)) {
pmd_t *pmd = pmd_offset(pud, addr);
if (!pmd_none(*pmd))
ptep = pte_offset_map(pmd, addr);
}
}
}
return ptep;
}
static void flush_cache_pages(struct vm_area_struct *vma, struct mm_struct *mm,
unsigned long start, unsigned long end)
{
unsigned long addr, pfn;
pte_t *ptep;
for (addr = start; addr < end; addr += PAGE_SIZE) {
ptep = get_ptep(mm->pgd, addr);
if (ptep) {
pfn = pte_pfn(*ptep);
flush_cache_page(vma, addr, pfn);
}
}
}
static void flush_user_cache_tlb(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
flush_user_dcache_range_asm(start, end);
if (vma->vm_flags & VM_EXEC)
flush_user_icache_range_asm(start, end);
flush_tlb_range(vma, start, end);
}
void flush_cache_mm(struct mm_struct *mm)
{
struct vm_area_struct *vma;
/* Flushing the whole cache on each cpu takes forever on
rp3440, etc. So, avoid it if the mm isn't too big. */
if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
mm_total_size(mm) >= parisc_cache_flush_threshold) {
if (mm->context)
flush_tlb_all();
flush_cache_all();
return;
}
preempt_disable();
if (mm->context == mfsp(3)) {
for (vma = mm->mmap; vma; vma = vma->vm_next)
flush_user_cache_tlb(vma, vma->vm_start, vma->vm_end);
preempt_enable();
return;
}
for (vma = mm->mmap; vma; vma = vma->vm_next)
flush_cache_pages(vma, mm, vma->vm_start, vma->vm_end);
preempt_enable();
}
void flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
end - start >= parisc_cache_flush_threshold) {
if (vma->vm_mm->context)
flush_tlb_range(vma, start, end);
flush_cache_all();
return;
}
preempt_disable();
if (vma->vm_mm->context == mfsp(3)) {
flush_user_cache_tlb(vma, start, end);
preempt_enable();
return;
}
flush_cache_pages(vma, vma->vm_mm, vma->vm_start, vma->vm_end);
preempt_enable();
}
void
flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
{
if (pfn_valid(pfn)) {
if (likely(vma->vm_mm->context)) {
flush_tlb_page(vma, vmaddr);
__flush_cache_page(vma, vmaddr, PFN_PHYS(pfn));
} else {
__purge_cache_page(vma, vmaddr, PFN_PHYS(pfn));
}
}
}
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;
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);