linux/arch/mips/mm/c-tx39.c
James Hogan 01882b4d5e MIPS: c-r4k: Split user/kernel flush_icache_range()
flush_icache_range() is used for both user addresses (i.e.
cacheflush(2)), and kernel addresses (as the API documentation
describes).

This isn't really suitable however for Enhanced Virtual Addressing (EVA)
where cache operations on usermode addresses must use a different
instruction, and the protected cache ops assume user addresses, making
flush_icache_range() ineffective on kernel addresses.

Split out a new __flush_icache_user_range() and
__local_flush_icache_user_range() for users which actually want to flush
usermode addresses (note that flush_icache_user_range() already exists
on various architectures but with different arguments).

The implementation of flush_icache_range() will be changed in an
upcoming commit to use unprotected normal cache ops so as to always work
on the kernel mode address space.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14152/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-10-04 16:13:57 +02:00

440 lines
11 KiB
C

/*
* r2300.c: R2000 and R3000 specific mmu/cache code.
*
* Copyright (C) 1996 David S. Miller (davem@davemloft.net)
*
* with a lot of changes to make this thing work for R3000s
* Tx39XX R4k style caches added. HK
* Copyright (C) 1998, 1999, 2000 Harald Koerfgen
* Copyright (C) 1998 Gleb Raiko & Vladimir Roganov
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/mm.h>
#include <asm/cacheops.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/isadep.h>
#include <asm/io.h>
#include <asm/bootinfo.h>
#include <asm/cpu.h>
/* For R3000 cores with R4000 style caches */
static unsigned long icache_size, dcache_size; /* Size in bytes */
#include <asm/r4kcache.h>
/* This sequence is required to ensure icache is disabled immediately */
#define TX39_STOP_STREAMING() \
__asm__ __volatile__( \
".set push\n\t" \
".set noreorder\n\t" \
"b 1f\n\t" \
"nop\n\t" \
"1:\n\t" \
".set pop" \
)
/* TX39H-style cache flush routines. */
static void tx39h_flush_icache_all(void)
{
unsigned long flags, config;
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
blast_icache16();
write_c0_conf(config);
local_irq_restore(flags);
}
static void tx39h_dma_cache_wback_inv(unsigned long addr, unsigned long size)
{
/* Catch bad driver code */
BUG_ON(size == 0);
iob();
blast_inv_dcache_range(addr, addr + size);
}
/* TX39H2,TX39H3 */
static inline void tx39_blast_dcache_page(unsigned long addr)
{
if (current_cpu_type() != CPU_TX3912)
blast_dcache16_page(addr);
}
static inline void tx39_blast_dcache_page_indexed(unsigned long addr)
{
blast_dcache16_page_indexed(addr);
}
static inline void tx39_blast_dcache(void)
{
blast_dcache16();
}
static inline void tx39_blast_icache_page(unsigned long addr)
{
unsigned long flags, config;
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
blast_icache16_page(addr);
write_c0_conf(config);
local_irq_restore(flags);
}
static inline void tx39_blast_icache_page_indexed(unsigned long addr)
{
unsigned long flags, config;
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
blast_icache16_page_indexed(addr);
write_c0_conf(config);
local_irq_restore(flags);
}
static inline void tx39_blast_icache(void)
{
unsigned long flags, config;
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
blast_icache16();
write_c0_conf(config);
local_irq_restore(flags);
}
static void tx39__flush_cache_vmap(void)
{
tx39_blast_dcache();
}
static void tx39__flush_cache_vunmap(void)
{
tx39_blast_dcache();
}
static inline void tx39_flush_cache_all(void)
{
if (!cpu_has_dc_aliases)
return;
tx39_blast_dcache();
}
static inline void tx39___flush_cache_all(void)
{
tx39_blast_dcache();
tx39_blast_icache();
}
static void tx39_flush_cache_mm(struct mm_struct *mm)
{
if (!cpu_has_dc_aliases)
return;
if (cpu_context(smp_processor_id(), mm) != 0)
tx39_blast_dcache();
}
static void tx39_flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if (!cpu_has_dc_aliases)
return;
if (!(cpu_context(smp_processor_id(), vma->vm_mm)))
return;
tx39_blast_dcache();
}
static void tx39_flush_cache_page(struct vm_area_struct *vma, unsigned long page, unsigned long pfn)
{
int exec = vma->vm_flags & VM_EXEC;
struct mm_struct *mm = vma->vm_mm;
pgd_t *pgdp;
pud_t *pudp;
pmd_t *pmdp;
pte_t *ptep;
/*
* If ownes no valid ASID yet, cannot possibly have gotten
* this page into the cache.
*/
if (cpu_context(smp_processor_id(), mm) == 0)
return;
page &= PAGE_MASK;
pgdp = pgd_offset(mm, page);
pudp = pud_offset(pgdp, page);
pmdp = pmd_offset(pudp, page);
ptep = pte_offset(pmdp, page);
/*
* If the page isn't marked valid, the page cannot possibly be
* in the cache.
*/
if (!(pte_val(*ptep) & _PAGE_PRESENT))
return;
/*
* Doing flushes for another ASID than the current one is
* too difficult since stupid R4k caches do a TLB translation
* for every cache flush operation. So we do indexed flushes
* in that case, which doesn't overly flush the cache too much.
*/
if ((mm == current->active_mm) && (pte_val(*ptep) & _PAGE_VALID)) {
if (cpu_has_dc_aliases || exec)
tx39_blast_dcache_page(page);
if (exec)
tx39_blast_icache_page(page);
return;
}
/*
* Do indexed flush, too much work to get the (possible) TLB refills
* to work correctly.
*/
if (cpu_has_dc_aliases || exec)
tx39_blast_dcache_page_indexed(page);
if (exec)
tx39_blast_icache_page_indexed(page);
}
static void local_tx39_flush_data_cache_page(void * addr)
{
tx39_blast_dcache_page((unsigned long)addr);
}
static void tx39_flush_data_cache_page(unsigned long addr)
{
tx39_blast_dcache_page(addr);
}
static void tx39_flush_icache_range(unsigned long start, unsigned long end)
{
if (end - start > dcache_size)
tx39_blast_dcache();
else
protected_blast_dcache_range(start, end);
if (end - start > icache_size)
tx39_blast_icache();
else {
unsigned long flags, config;
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
protected_blast_icache_range(start, end);
write_c0_conf(config);
local_irq_restore(flags);
}
}
static void tx39_flush_kernel_vmap_range(unsigned long vaddr, int size)
{
BUG();
}
static void tx39_dma_cache_wback_inv(unsigned long addr, unsigned long size)
{
unsigned long end;
if (((size | addr) & (PAGE_SIZE - 1)) == 0) {
end = addr + size;
do {
tx39_blast_dcache_page(addr);
addr += PAGE_SIZE;
} while(addr != end);
} else if (size > dcache_size) {
tx39_blast_dcache();
} else {
blast_dcache_range(addr, addr + size);
}
}
static void tx39_dma_cache_inv(unsigned long addr, unsigned long size)
{
unsigned long end;
if (((size | addr) & (PAGE_SIZE - 1)) == 0) {
end = addr + size;
do {
tx39_blast_dcache_page(addr);
addr += PAGE_SIZE;
} while(addr != end);
} else if (size > dcache_size) {
tx39_blast_dcache();
} else {
blast_inv_dcache_range(addr, addr + size);
}
}
static void tx39_flush_cache_sigtramp(unsigned long addr)
{
unsigned long ic_lsize = current_cpu_data.icache.linesz;
unsigned long dc_lsize = current_cpu_data.dcache.linesz;
unsigned long config;
unsigned long flags;
protected_writeback_dcache_line(addr & ~(dc_lsize - 1));
/* disable icache (set ICE#) */
local_irq_save(flags);
config = read_c0_conf();
write_c0_conf(config & ~TX39_CONF_ICE);
TX39_STOP_STREAMING();
protected_flush_icache_line(addr & ~(ic_lsize - 1));
write_c0_conf(config);
local_irq_restore(flags);
}
static __init void tx39_probe_cache(void)
{
unsigned long config;
config = read_c0_conf();
icache_size = 1 << (10 + ((config & TX39_CONF_ICS_MASK) >>
TX39_CONF_ICS_SHIFT));
dcache_size = 1 << (10 + ((config & TX39_CONF_DCS_MASK) >>
TX39_CONF_DCS_SHIFT));
current_cpu_data.icache.linesz = 16;
switch (current_cpu_type()) {
case CPU_TX3912:
current_cpu_data.icache.ways = 1;
current_cpu_data.dcache.ways = 1;
current_cpu_data.dcache.linesz = 4;
break;
case CPU_TX3927:
current_cpu_data.icache.ways = 2;
current_cpu_data.dcache.ways = 2;
current_cpu_data.dcache.linesz = 16;
break;
case CPU_TX3922:
default:
current_cpu_data.icache.ways = 1;
current_cpu_data.dcache.ways = 1;
current_cpu_data.dcache.linesz = 16;
break;
}
}
void tx39_cache_init(void)
{
extern void build_clear_page(void);
extern void build_copy_page(void);
unsigned long config;
config = read_c0_conf();
config &= ~TX39_CONF_WBON;
write_c0_conf(config);
tx39_probe_cache();
switch (current_cpu_type()) {
case CPU_TX3912:
/* TX39/H core (writethru direct-map cache) */
__flush_cache_vmap = tx39__flush_cache_vmap;
__flush_cache_vunmap = tx39__flush_cache_vunmap;
flush_cache_all = tx39h_flush_icache_all;
__flush_cache_all = tx39h_flush_icache_all;
flush_cache_mm = (void *) tx39h_flush_icache_all;
flush_cache_range = (void *) tx39h_flush_icache_all;
flush_cache_page = (void *) tx39h_flush_icache_all;
flush_icache_range = (void *) tx39h_flush_icache_all;
local_flush_icache_range = (void *) tx39h_flush_icache_all;
flush_cache_sigtramp = (void *) tx39h_flush_icache_all;
local_flush_data_cache_page = (void *) tx39h_flush_icache_all;
flush_data_cache_page = (void *) tx39h_flush_icache_all;
_dma_cache_wback_inv = tx39h_dma_cache_wback_inv;
shm_align_mask = PAGE_SIZE - 1;
break;
case CPU_TX3922:
case CPU_TX3927:
default:
/* TX39/H2,H3 core (writeback 2way-set-associative cache) */
/* board-dependent init code may set WBON */
__flush_cache_vmap = tx39__flush_cache_vmap;
__flush_cache_vunmap = tx39__flush_cache_vunmap;
flush_cache_all = tx39_flush_cache_all;
__flush_cache_all = tx39___flush_cache_all;
flush_cache_mm = tx39_flush_cache_mm;
flush_cache_range = tx39_flush_cache_range;
flush_cache_page = tx39_flush_cache_page;
flush_icache_range = tx39_flush_icache_range;
local_flush_icache_range = tx39_flush_icache_range;
__flush_kernel_vmap_range = tx39_flush_kernel_vmap_range;
flush_cache_sigtramp = tx39_flush_cache_sigtramp;
local_flush_data_cache_page = local_tx39_flush_data_cache_page;
flush_data_cache_page = tx39_flush_data_cache_page;
_dma_cache_wback_inv = tx39_dma_cache_wback_inv;
_dma_cache_wback = tx39_dma_cache_wback_inv;
_dma_cache_inv = tx39_dma_cache_inv;
shm_align_mask = max_t(unsigned long,
(dcache_size / current_cpu_data.dcache.ways) - 1,
PAGE_SIZE - 1);
break;
}
__flush_icache_user_range = flush_icache_range;
__local_flush_icache_user_range = local_flush_icache_range;
current_cpu_data.icache.waysize = icache_size / current_cpu_data.icache.ways;
current_cpu_data.dcache.waysize = dcache_size / current_cpu_data.dcache.ways;
current_cpu_data.icache.sets =
current_cpu_data.icache.waysize / current_cpu_data.icache.linesz;
current_cpu_data.dcache.sets =
current_cpu_data.dcache.waysize / current_cpu_data.dcache.linesz;
if (current_cpu_data.dcache.waysize > PAGE_SIZE)
current_cpu_data.dcache.flags |= MIPS_CACHE_ALIASES;
current_cpu_data.icache.waybit = 0;
current_cpu_data.dcache.waybit = 0;
printk("Primary instruction cache %ldkB, linesize %d bytes\n",
icache_size >> 10, current_cpu_data.icache.linesz);
printk("Primary data cache %ldkB, linesize %d bytes\n",
dcache_size >> 10, current_cpu_data.dcache.linesz);
build_clear_page();
build_copy_page();
tx39h_flush_icache_all();
}