WSL2-Linux-Kernel/arch/m68k/sun3/sun3dvma.c

381 строка
7.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/m68k/sun3/sun3dvma.c
*
* Copyright (C) 2000 Sam Creasey
*
* Contains common routines for sun3/sun3x DVMA management.
*/
#include <linux/memblock.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <asm/page.h>
#include <asm/dvma.h>
#undef DVMA_DEBUG
#ifdef CONFIG_SUN3X
extern void dvma_unmap_iommu(unsigned long baddr, int len);
#else
static inline void dvma_unmap_iommu(unsigned long a, int b)
{
}
#endif
#ifdef CONFIG_SUN3
extern void sun3_dvma_init(void);
#endif
static unsigned long *iommu_use;
#define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
#define dvma_entry_use(baddr) (iommu_use[dvma_index(baddr)])
struct hole {
unsigned long start;
unsigned long end;
unsigned long size;
struct list_head list;
};
static struct list_head hole_list;
static struct list_head hole_cache;
static struct hole initholes[64];
#ifdef DVMA_DEBUG
static unsigned long dvma_allocs;
static unsigned long dvma_frees;
static unsigned long long dvma_alloc_bytes;
static unsigned long long dvma_free_bytes;
static void print_use(void)
{
int i;
int j = 0;
pr_info("dvma entry usage:\n");
for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
if(!iommu_use[i])
continue;
j++;
pr_info("dvma entry: %08x len %08lx\n",
(i << DVMA_PAGE_SHIFT) + DVMA_START, iommu_use[i]);
}
pr_info("%d entries in use total\n", j);
pr_info("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
pr_info("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
dvma_free_bytes);
}
static void print_holes(struct list_head *holes)
{
struct list_head *cur;
struct hole *hole;
pr_info("listing dvma holes\n");
list_for_each(cur, holes) {
hole = list_entry(cur, struct hole, list);
if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
continue;
pr_info("hole: start %08lx end %08lx size %08lx\n",
hole->start, hole->end, hole->size);
}
pr_info("end of hole listing...\n");
}
#endif /* DVMA_DEBUG */
static inline int refill(void)
{
struct hole *hole;
struct hole *prev = NULL;
struct list_head *cur;
int ret = 0;
list_for_each(cur, &hole_list) {
hole = list_entry(cur, struct hole, list);
if(!prev) {
prev = hole;
continue;
}
if(hole->end == prev->start) {
hole->size += prev->size;
hole->end = prev->end;
list_move(&(prev->list), &hole_cache);
ret++;
}
}
return ret;
}
static inline struct hole *rmcache(void)
{
struct hole *ret;
if(list_empty(&hole_cache)) {
if(!refill()) {
pr_crit("out of dvma hole cache!\n");
BUG();
}
}
ret = list_entry(hole_cache.next, struct hole, list);
list_del(&(ret->list));
return ret;
}
static inline unsigned long get_baddr(int len, unsigned long align)
{
struct list_head *cur;
struct hole *hole;
if(list_empty(&hole_list)) {
#ifdef DVMA_DEBUG
pr_crit("out of dvma holes! (printing hole cache)\n");
print_holes(&hole_cache);
print_use();
#endif
BUG();
}
list_for_each(cur, &hole_list) {
unsigned long newlen;
hole = list_entry(cur, struct hole, list);
if(align > DVMA_PAGE_SIZE)
newlen = len + ((hole->end - len) & (align-1));
else
newlen = len;
if(hole->size > newlen) {
hole->end -= newlen;
hole->size -= newlen;
dvma_entry_use(hole->end) = newlen;
#ifdef DVMA_DEBUG
dvma_allocs++;
dvma_alloc_bytes += newlen;
#endif
return hole->end;
} else if(hole->size == newlen) {
list_move(&(hole->list), &hole_cache);
dvma_entry_use(hole->start) = newlen;
#ifdef DVMA_DEBUG
dvma_allocs++;
dvma_alloc_bytes += newlen;
#endif
return hole->start;
}
}
pr_crit("unable to find dvma hole!\n");
BUG();
return 0;
}
static inline int free_baddr(unsigned long baddr)
{
unsigned long len;
struct hole *hole;
struct list_head *cur;
unsigned long orig_baddr;
orig_baddr = baddr;
len = dvma_entry_use(baddr);
dvma_entry_use(baddr) = 0;
baddr &= DVMA_PAGE_MASK;
dvma_unmap_iommu(baddr, len);
#ifdef DVMA_DEBUG
dvma_frees++;
dvma_free_bytes += len;
#endif
list_for_each(cur, &hole_list) {
hole = list_entry(cur, struct hole, list);
if(hole->end == baddr) {
hole->end += len;
hole->size += len;
return 0;
} else if(hole->start == (baddr + len)) {
hole->start = baddr;
hole->size += len;
return 0;
}
}
hole = rmcache();
hole->start = baddr;
hole->end = baddr + len;
hole->size = len;
// list_add_tail(&(hole->list), cur);
list_add(&(hole->list), cur);
return 0;
}
void __init dvma_init(void)
{
struct hole *hole;
int i;
INIT_LIST_HEAD(&hole_list);
INIT_LIST_HEAD(&hole_cache);
/* prepare the hole cache */
for(i = 0; i < 64; i++)
list_add(&(initholes[i].list), &hole_cache);
hole = rmcache();
hole->start = DVMA_START;
hole->end = DVMA_END;
hole->size = DVMA_SIZE;
list_add(&(hole->list), &hole_list);
iommu_use = memblock_alloc(IOMMU_TOTAL_ENTRIES * sizeof(unsigned long),
SMP_CACHE_BYTES);
if (!iommu_use)
panic("%s: Failed to allocate %zu bytes\n", __func__,
IOMMU_TOTAL_ENTRIES * sizeof(unsigned long));
dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
#ifdef CONFIG_SUN3
sun3_dvma_init();
#endif
}
unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
{
unsigned long baddr;
unsigned long off;
if(!len)
len = 0x800;
if(!kaddr || !len) {
// pr_err("error: kaddr %lx len %x\n", kaddr, len);
// *(int *)4 = 0;
return 0;
}
pr_debug("dvma_map request %08x bytes from %08lx\n", len, kaddr);
off = kaddr & ~DVMA_PAGE_MASK;
kaddr &= PAGE_MASK;
len += off;
len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
if(align == 0)
align = DVMA_PAGE_SIZE;
else
align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
baddr = get_baddr(len, align);
// pr_info("using baddr %lx\n", baddr);
if(!dvma_map_iommu(kaddr, baddr, len))
return (baddr + off);
pr_crit("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr,
len);
BUG();
return 0;
}
EXPORT_SYMBOL(dvma_map_align);
void dvma_unmap(void *baddr)
{
unsigned long addr;
addr = (unsigned long)baddr;
/* check if this is a vme mapping */
if(!(addr & 0x00f00000))
addr |= 0xf00000;
free_baddr(addr);
return;
}
EXPORT_SYMBOL(dvma_unmap);
void *dvma_malloc_align(unsigned long len, unsigned long align)
{
unsigned long kaddr;
unsigned long baddr;
unsigned long vaddr;
if(!len)
return NULL;
pr_debug("dvma_malloc request %lx bytes\n", len);
len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
return NULL;
if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
free_pages(kaddr, get_order(len));
return NULL;
}
vaddr = dvma_btov(baddr);
if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
dvma_unmap((void *)baddr);
free_pages(kaddr, get_order(len));
return NULL;
}
pr_debug("mapped %08lx bytes %08lx kern -> %08lx bus\n", len, kaddr,
baddr);
return (void *)vaddr;
}
EXPORT_SYMBOL(dvma_malloc_align);
void dvma_free(void *vaddr)
{
return;
}
EXPORT_SYMBOL(dvma_free);