546 строки
13 KiB
C
546 строки
13 KiB
C
/*
|
|
* Register cache access API - rbtree caching support
|
|
*
|
|
* Copyright 2011 Wolfson Microelectronics plc
|
|
*
|
|
* Author: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/debugfs.h>
|
|
#include <linux/device.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include "internal.h"
|
|
|
|
static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
|
|
unsigned int value);
|
|
static int regcache_rbtree_exit(struct regmap *map);
|
|
|
|
struct regcache_rbtree_node {
|
|
/* block of adjacent registers */
|
|
void *block;
|
|
/* Which registers are present */
|
|
long *cache_present;
|
|
/* base register handled by this block */
|
|
unsigned int base_reg;
|
|
/* number of registers available in the block */
|
|
unsigned int blklen;
|
|
/* the actual rbtree node holding this block */
|
|
struct rb_node node;
|
|
} __attribute__ ((packed));
|
|
|
|
struct regcache_rbtree_ctx {
|
|
struct rb_root root;
|
|
struct regcache_rbtree_node *cached_rbnode;
|
|
};
|
|
|
|
static inline void regcache_rbtree_get_base_top_reg(
|
|
struct regmap *map,
|
|
struct regcache_rbtree_node *rbnode,
|
|
unsigned int *base, unsigned int *top)
|
|
{
|
|
*base = rbnode->base_reg;
|
|
*top = rbnode->base_reg + ((rbnode->blklen - 1) * map->reg_stride);
|
|
}
|
|
|
|
static unsigned int regcache_rbtree_get_register(struct regmap *map,
|
|
struct regcache_rbtree_node *rbnode, unsigned int idx)
|
|
{
|
|
return regcache_get_val(map, rbnode->block, idx);
|
|
}
|
|
|
|
static void regcache_rbtree_set_register(struct regmap *map,
|
|
struct regcache_rbtree_node *rbnode,
|
|
unsigned int idx, unsigned int val)
|
|
{
|
|
set_bit(idx, rbnode->cache_present);
|
|
regcache_set_val(map, rbnode->block, idx, val);
|
|
}
|
|
|
|
static struct regcache_rbtree_node *regcache_rbtree_lookup(struct regmap *map,
|
|
unsigned int reg)
|
|
{
|
|
struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
|
|
struct rb_node *node;
|
|
struct regcache_rbtree_node *rbnode;
|
|
unsigned int base_reg, top_reg;
|
|
|
|
rbnode = rbtree_ctx->cached_rbnode;
|
|
if (rbnode) {
|
|
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
|
|
&top_reg);
|
|
if (reg >= base_reg && reg <= top_reg)
|
|
return rbnode;
|
|
}
|
|
|
|
node = rbtree_ctx->root.rb_node;
|
|
while (node) {
|
|
rbnode = container_of(node, struct regcache_rbtree_node, node);
|
|
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
|
|
&top_reg);
|
|
if (reg >= base_reg && reg <= top_reg) {
|
|
rbtree_ctx->cached_rbnode = rbnode;
|
|
return rbnode;
|
|
} else if (reg > top_reg) {
|
|
node = node->rb_right;
|
|
} else if (reg < base_reg) {
|
|
node = node->rb_left;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int regcache_rbtree_insert(struct regmap *map, struct rb_root *root,
|
|
struct regcache_rbtree_node *rbnode)
|
|
{
|
|
struct rb_node **new, *parent;
|
|
struct regcache_rbtree_node *rbnode_tmp;
|
|
unsigned int base_reg_tmp, top_reg_tmp;
|
|
unsigned int base_reg;
|
|
|
|
parent = NULL;
|
|
new = &root->rb_node;
|
|
while (*new) {
|
|
rbnode_tmp = container_of(*new, struct regcache_rbtree_node,
|
|
node);
|
|
/* base and top registers of the current rbnode */
|
|
regcache_rbtree_get_base_top_reg(map, rbnode_tmp, &base_reg_tmp,
|
|
&top_reg_tmp);
|
|
/* base register of the rbnode to be added */
|
|
base_reg = rbnode->base_reg;
|
|
parent = *new;
|
|
/* if this register has already been inserted, just return */
|
|
if (base_reg >= base_reg_tmp &&
|
|
base_reg <= top_reg_tmp)
|
|
return 0;
|
|
else if (base_reg > top_reg_tmp)
|
|
new = &((*new)->rb_right);
|
|
else if (base_reg < base_reg_tmp)
|
|
new = &((*new)->rb_left);
|
|
}
|
|
|
|
/* insert the node into the rbtree */
|
|
rb_link_node(&rbnode->node, parent, new);
|
|
rb_insert_color(&rbnode->node, root);
|
|
|
|
return 1;
|
|
}
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
static int rbtree_show(struct seq_file *s, void *ignored)
|
|
{
|
|
struct regmap *map = s->private;
|
|
struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
|
|
struct regcache_rbtree_node *n;
|
|
struct rb_node *node;
|
|
unsigned int base, top;
|
|
size_t mem_size;
|
|
int nodes = 0;
|
|
int registers = 0;
|
|
int this_registers, average;
|
|
|
|
map->lock(map->lock_arg);
|
|
|
|
mem_size = sizeof(*rbtree_ctx);
|
|
|
|
for (node = rb_first(&rbtree_ctx->root); node != NULL;
|
|
node = rb_next(node)) {
|
|
n = container_of(node, struct regcache_rbtree_node, node);
|
|
mem_size += sizeof(*n);
|
|
mem_size += (n->blklen * map->cache_word_size);
|
|
mem_size += BITS_TO_LONGS(n->blklen) * sizeof(long);
|
|
|
|
regcache_rbtree_get_base_top_reg(map, n, &base, &top);
|
|
this_registers = ((top - base) / map->reg_stride) + 1;
|
|
seq_printf(s, "%x-%x (%d)\n", base, top, this_registers);
|
|
|
|
nodes++;
|
|
registers += this_registers;
|
|
}
|
|
|
|
if (nodes)
|
|
average = registers / nodes;
|
|
else
|
|
average = 0;
|
|
|
|
seq_printf(s, "%d nodes, %d registers, average %d registers, used %zu bytes\n",
|
|
nodes, registers, average, mem_size);
|
|
|
|
map->unlock(map->lock_arg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rbtree_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, rbtree_show, inode->i_private);
|
|
}
|
|
|
|
static const struct file_operations rbtree_fops = {
|
|
.open = rbtree_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
|
|
static void rbtree_debugfs_init(struct regmap *map)
|
|
{
|
|
debugfs_create_file("rbtree", 0400, map->debugfs, map, &rbtree_fops);
|
|
}
|
|
#endif
|
|
|
|
static int regcache_rbtree_init(struct regmap *map)
|
|
{
|
|
struct regcache_rbtree_ctx *rbtree_ctx;
|
|
int i;
|
|
int ret;
|
|
|
|
map->cache = kmalloc(sizeof *rbtree_ctx, GFP_KERNEL);
|
|
if (!map->cache)
|
|
return -ENOMEM;
|
|
|
|
rbtree_ctx = map->cache;
|
|
rbtree_ctx->root = RB_ROOT;
|
|
rbtree_ctx->cached_rbnode = NULL;
|
|
|
|
for (i = 0; i < map->num_reg_defaults; i++) {
|
|
ret = regcache_rbtree_write(map,
|
|
map->reg_defaults[i].reg,
|
|
map->reg_defaults[i].def);
|
|
if (ret)
|
|
goto err;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err:
|
|
regcache_rbtree_exit(map);
|
|
return ret;
|
|
}
|
|
|
|
static int regcache_rbtree_exit(struct regmap *map)
|
|
{
|
|
struct rb_node *next;
|
|
struct regcache_rbtree_ctx *rbtree_ctx;
|
|
struct regcache_rbtree_node *rbtree_node;
|
|
|
|
/* if we've already been called then just return */
|
|
rbtree_ctx = map->cache;
|
|
if (!rbtree_ctx)
|
|
return 0;
|
|
|
|
/* free up the rbtree */
|
|
next = rb_first(&rbtree_ctx->root);
|
|
while (next) {
|
|
rbtree_node = rb_entry(next, struct regcache_rbtree_node, node);
|
|
next = rb_next(&rbtree_node->node);
|
|
rb_erase(&rbtree_node->node, &rbtree_ctx->root);
|
|
kfree(rbtree_node->cache_present);
|
|
kfree(rbtree_node->block);
|
|
kfree(rbtree_node);
|
|
}
|
|
|
|
/* release the resources */
|
|
kfree(map->cache);
|
|
map->cache = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int regcache_rbtree_read(struct regmap *map,
|
|
unsigned int reg, unsigned int *value)
|
|
{
|
|
struct regcache_rbtree_node *rbnode;
|
|
unsigned int reg_tmp;
|
|
|
|
rbnode = regcache_rbtree_lookup(map, reg);
|
|
if (rbnode) {
|
|
reg_tmp = (reg - rbnode->base_reg) / map->reg_stride;
|
|
if (!test_bit(reg_tmp, rbnode->cache_present))
|
|
return -ENOENT;
|
|
*value = regcache_rbtree_get_register(map, rbnode, reg_tmp);
|
|
} else {
|
|
return -ENOENT;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int regcache_rbtree_insert_to_block(struct regmap *map,
|
|
struct regcache_rbtree_node *rbnode,
|
|
unsigned int base_reg,
|
|
unsigned int top_reg,
|
|
unsigned int reg,
|
|
unsigned int value)
|
|
{
|
|
unsigned int blklen;
|
|
unsigned int pos, offset;
|
|
unsigned long *present;
|
|
u8 *blk;
|
|
|
|
blklen = (top_reg - base_reg) / map->reg_stride + 1;
|
|
pos = (reg - base_reg) / map->reg_stride;
|
|
offset = (rbnode->base_reg - base_reg) / map->reg_stride;
|
|
|
|
blk = krealloc(rbnode->block,
|
|
blklen * map->cache_word_size,
|
|
GFP_KERNEL);
|
|
if (!blk)
|
|
return -ENOMEM;
|
|
|
|
if (BITS_TO_LONGS(blklen) > BITS_TO_LONGS(rbnode->blklen)) {
|
|
present = krealloc(rbnode->cache_present,
|
|
BITS_TO_LONGS(blklen) * sizeof(*present),
|
|
GFP_KERNEL);
|
|
if (!present) {
|
|
kfree(blk);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
memset(present + BITS_TO_LONGS(rbnode->blklen), 0,
|
|
(BITS_TO_LONGS(blklen) - BITS_TO_LONGS(rbnode->blklen))
|
|
* sizeof(*present));
|
|
} else {
|
|
present = rbnode->cache_present;
|
|
}
|
|
|
|
/* insert the register value in the correct place in the rbnode block */
|
|
if (pos == 0) {
|
|
memmove(blk + offset * map->cache_word_size,
|
|
blk, rbnode->blklen * map->cache_word_size);
|
|
bitmap_shift_left(present, present, offset, blklen);
|
|
}
|
|
|
|
/* update the rbnode block, its size and the base register */
|
|
rbnode->block = blk;
|
|
rbnode->blklen = blklen;
|
|
rbnode->base_reg = base_reg;
|
|
rbnode->cache_present = present;
|
|
|
|
regcache_rbtree_set_register(map, rbnode, pos, value);
|
|
return 0;
|
|
}
|
|
|
|
static struct regcache_rbtree_node *
|
|
regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
|
|
{
|
|
struct regcache_rbtree_node *rbnode;
|
|
const struct regmap_range *range;
|
|
int i;
|
|
|
|
rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
|
|
if (!rbnode)
|
|
return NULL;
|
|
|
|
/* If there is a read table then use it to guess at an allocation */
|
|
if (map->rd_table) {
|
|
for (i = 0; i < map->rd_table->n_yes_ranges; i++) {
|
|
if (regmap_reg_in_range(reg,
|
|
&map->rd_table->yes_ranges[i]))
|
|
break;
|
|
}
|
|
|
|
if (i != map->rd_table->n_yes_ranges) {
|
|
range = &map->rd_table->yes_ranges[i];
|
|
rbnode->blklen = (range->range_max - range->range_min) /
|
|
map->reg_stride + 1;
|
|
rbnode->base_reg = range->range_min;
|
|
}
|
|
}
|
|
|
|
if (!rbnode->blklen) {
|
|
rbnode->blklen = 1;
|
|
rbnode->base_reg = reg;
|
|
}
|
|
|
|
rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
|
|
GFP_KERNEL);
|
|
if (!rbnode->block)
|
|
goto err_free;
|
|
|
|
rbnode->cache_present = kzalloc(BITS_TO_LONGS(rbnode->blklen) *
|
|
sizeof(*rbnode->cache_present), GFP_KERNEL);
|
|
if (!rbnode->cache_present)
|
|
goto err_free_block;
|
|
|
|
return rbnode;
|
|
|
|
err_free_block:
|
|
kfree(rbnode->block);
|
|
err_free:
|
|
kfree(rbnode);
|
|
return NULL;
|
|
}
|
|
|
|
static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
|
|
unsigned int value)
|
|
{
|
|
struct regcache_rbtree_ctx *rbtree_ctx;
|
|
struct regcache_rbtree_node *rbnode, *rbnode_tmp;
|
|
struct rb_node *node;
|
|
unsigned int reg_tmp;
|
|
int ret;
|
|
|
|
rbtree_ctx = map->cache;
|
|
|
|
/* if we can't locate it in the cached rbnode we'll have
|
|
* to traverse the rbtree looking for it.
|
|
*/
|
|
rbnode = regcache_rbtree_lookup(map, reg);
|
|
if (rbnode) {
|
|
reg_tmp = (reg - rbnode->base_reg) / map->reg_stride;
|
|
regcache_rbtree_set_register(map, rbnode, reg_tmp, value);
|
|
} else {
|
|
unsigned int base_reg, top_reg;
|
|
unsigned int new_base_reg, new_top_reg;
|
|
unsigned int min, max;
|
|
unsigned int max_dist;
|
|
|
|
max_dist = map->reg_stride * sizeof(*rbnode_tmp) /
|
|
map->cache_word_size;
|
|
if (reg < max_dist)
|
|
min = 0;
|
|
else
|
|
min = reg - max_dist;
|
|
max = reg + max_dist;
|
|
|
|
/* look for an adjacent register to the one we are about to add */
|
|
for (node = rb_first(&rbtree_ctx->root); node;
|
|
node = rb_next(node)) {
|
|
rbnode_tmp = rb_entry(node, struct regcache_rbtree_node,
|
|
node);
|
|
|
|
regcache_rbtree_get_base_top_reg(map, rbnode_tmp,
|
|
&base_reg, &top_reg);
|
|
|
|
if (base_reg <= max && top_reg >= min) {
|
|
new_base_reg = min(reg, base_reg);
|
|
new_top_reg = max(reg, top_reg);
|
|
} else {
|
|
continue;
|
|
}
|
|
|
|
ret = regcache_rbtree_insert_to_block(map, rbnode_tmp,
|
|
new_base_reg,
|
|
new_top_reg, reg,
|
|
value);
|
|
if (ret)
|
|
return ret;
|
|
rbtree_ctx->cached_rbnode = rbnode_tmp;
|
|
return 0;
|
|
}
|
|
|
|
/* We did not manage to find a place to insert it in
|
|
* an existing block so create a new rbnode.
|
|
*/
|
|
rbnode = regcache_rbtree_node_alloc(map, reg);
|
|
if (!rbnode)
|
|
return -ENOMEM;
|
|
regcache_rbtree_set_register(map, rbnode,
|
|
reg - rbnode->base_reg, value);
|
|
regcache_rbtree_insert(map, &rbtree_ctx->root, rbnode);
|
|
rbtree_ctx->cached_rbnode = rbnode;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int regcache_rbtree_sync(struct regmap *map, unsigned int min,
|
|
unsigned int max)
|
|
{
|
|
struct regcache_rbtree_ctx *rbtree_ctx;
|
|
struct rb_node *node;
|
|
struct regcache_rbtree_node *rbnode;
|
|
unsigned int base_reg, top_reg;
|
|
unsigned int start, end;
|
|
int ret;
|
|
|
|
rbtree_ctx = map->cache;
|
|
for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
|
|
rbnode = rb_entry(node, struct regcache_rbtree_node, node);
|
|
|
|
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
|
|
&top_reg);
|
|
if (base_reg > max)
|
|
break;
|
|
if (top_reg < min)
|
|
continue;
|
|
|
|
if (min > base_reg)
|
|
start = (min - base_reg) / map->reg_stride;
|
|
else
|
|
start = 0;
|
|
|
|
if (max < top_reg)
|
|
end = (max - base_reg) / map->reg_stride + 1;
|
|
else
|
|
end = rbnode->blklen;
|
|
|
|
ret = regcache_sync_block(map, rbnode->block,
|
|
rbnode->cache_present,
|
|
rbnode->base_reg, start, end);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
|
|
return regmap_async_complete(map);
|
|
}
|
|
|
|
static int regcache_rbtree_drop(struct regmap *map, unsigned int min,
|
|
unsigned int max)
|
|
{
|
|
struct regcache_rbtree_ctx *rbtree_ctx;
|
|
struct regcache_rbtree_node *rbnode;
|
|
struct rb_node *node;
|
|
unsigned int base_reg, top_reg;
|
|
unsigned int start, end;
|
|
|
|
rbtree_ctx = map->cache;
|
|
for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
|
|
rbnode = rb_entry(node, struct regcache_rbtree_node, node);
|
|
|
|
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
|
|
&top_reg);
|
|
if (base_reg > max)
|
|
break;
|
|
if (top_reg < min)
|
|
continue;
|
|
|
|
if (min > base_reg)
|
|
start = (min - base_reg) / map->reg_stride;
|
|
else
|
|
start = 0;
|
|
|
|
if (max < top_reg)
|
|
end = (max - base_reg) / map->reg_stride + 1;
|
|
else
|
|
end = rbnode->blklen;
|
|
|
|
bitmap_clear(rbnode->cache_present, start, end - start);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct regcache_ops regcache_rbtree_ops = {
|
|
.type = REGCACHE_RBTREE,
|
|
.name = "rbtree",
|
|
.init = regcache_rbtree_init,
|
|
.exit = regcache_rbtree_exit,
|
|
#ifdef CONFIG_DEBUG_FS
|
|
.debugfs_init = rbtree_debugfs_init,
|
|
#endif
|
|
.read = regcache_rbtree_read,
|
|
.write = regcache_rbtree_write,
|
|
.sync = regcache_rbtree_sync,
|
|
.drop = regcache_rbtree_drop,
|
|
};
|