linux/drivers/video/omap2/vram.c
Tomi Valkeinen 2a803c887b OMAPDSS: Remove video SRAM support
OMAP SRAM can be used as video memory on OMAP1 and 2. However, there
usually is very little SRAM available, thus limiting its use, and no
board supported by the kernel currently uses it.

This patch removes the use of SRAM as video ram for the omapdss driver
to simplify memory handling.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
2012-02-23 09:38:26 +02:00

571 lines
12 KiB
C

/*
* VRAM manager for OMAP
*
* Copyright (C) 2009 Nokia Corporation
* Author: Tomi Valkeinen <tomi.valkeinen@nokia.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.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/*#define DEBUG*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/memblock.h>
#include <linux/completion.h>
#include <linux/debugfs.h>
#include <linux/jiffies.h>
#include <linux/module.h>
#include <asm/setup.h>
#include <plat/vram.h>
#include <plat/dma.h>
#ifdef DEBUG
#define DBG(format, ...) pr_debug("VRAM: " format, ## __VA_ARGS__)
#else
#define DBG(format, ...)
#endif
/* postponed regions are used to temporarily store region information at boot
* time when we cannot yet allocate the region list */
#define MAX_POSTPONED_REGIONS 10
static bool vram_initialized;
static int postponed_cnt;
static struct {
unsigned long paddr;
size_t size;
} postponed_regions[MAX_POSTPONED_REGIONS];
struct vram_alloc {
struct list_head list;
unsigned long paddr;
unsigned pages;
};
struct vram_region {
struct list_head list;
struct list_head alloc_list;
unsigned long paddr;
unsigned pages;
};
static DEFINE_MUTEX(region_mutex);
static LIST_HEAD(region_list);
static struct vram_region *omap_vram_create_region(unsigned long paddr,
unsigned pages)
{
struct vram_region *rm;
rm = kzalloc(sizeof(*rm), GFP_KERNEL);
if (rm) {
INIT_LIST_HEAD(&rm->alloc_list);
rm->paddr = paddr;
rm->pages = pages;
}
return rm;
}
#if 0
static void omap_vram_free_region(struct vram_region *vr)
{
list_del(&vr->list);
kfree(vr);
}
#endif
static struct vram_alloc *omap_vram_create_allocation(struct vram_region *vr,
unsigned long paddr, unsigned pages)
{
struct vram_alloc *va;
struct vram_alloc *new;
new = kzalloc(sizeof(*va), GFP_KERNEL);
if (!new)
return NULL;
new->paddr = paddr;
new->pages = pages;
list_for_each_entry(va, &vr->alloc_list, list) {
if (va->paddr > new->paddr)
break;
}
list_add_tail(&new->list, &va->list);
return new;
}
static void omap_vram_free_allocation(struct vram_alloc *va)
{
list_del(&va->list);
kfree(va);
}
int omap_vram_add_region(unsigned long paddr, size_t size)
{
struct vram_region *rm;
unsigned pages;
if (vram_initialized) {
DBG("adding region paddr %08lx size %d\n",
paddr, size);
size &= PAGE_MASK;
pages = size >> PAGE_SHIFT;
rm = omap_vram_create_region(paddr, pages);
if (rm == NULL)
return -ENOMEM;
list_add(&rm->list, &region_list);
} else {
if (postponed_cnt == MAX_POSTPONED_REGIONS)
return -ENOMEM;
postponed_regions[postponed_cnt].paddr = paddr;
postponed_regions[postponed_cnt].size = size;
++postponed_cnt;
}
return 0;
}
int omap_vram_free(unsigned long paddr, size_t size)
{
struct vram_region *rm;
struct vram_alloc *alloc;
unsigned start, end;
DBG("free mem paddr %08lx size %d\n", paddr, size);
size = PAGE_ALIGN(size);
mutex_lock(&region_mutex);
list_for_each_entry(rm, &region_list, list) {
list_for_each_entry(alloc, &rm->alloc_list, list) {
start = alloc->paddr;
end = alloc->paddr + (alloc->pages >> PAGE_SHIFT);
if (start >= paddr && end < paddr + size)
goto found;
}
}
mutex_unlock(&region_mutex);
return -EINVAL;
found:
omap_vram_free_allocation(alloc);
mutex_unlock(&region_mutex);
return 0;
}
EXPORT_SYMBOL(omap_vram_free);
static int _omap_vram_reserve(unsigned long paddr, unsigned pages)
{
struct vram_region *rm;
struct vram_alloc *alloc;
size_t size;
size = pages << PAGE_SHIFT;
list_for_each_entry(rm, &region_list, list) {
unsigned long start, end;
DBG("checking region %lx %d\n", rm->paddr, rm->pages);
start = rm->paddr;
end = start + (rm->pages << PAGE_SHIFT) - 1;
if (start > paddr || end < paddr + size - 1)
continue;
DBG("block ok, checking allocs\n");
list_for_each_entry(alloc, &rm->alloc_list, list) {
end = alloc->paddr - 1;
if (start <= paddr && end >= paddr + size - 1)
goto found;
start = alloc->paddr + (alloc->pages << PAGE_SHIFT);
}
end = rm->paddr + (rm->pages << PAGE_SHIFT) - 1;
if (!(start <= paddr && end >= paddr + size - 1))
continue;
found:
DBG("found area start %lx, end %lx\n", start, end);
if (omap_vram_create_allocation(rm, paddr, pages) == NULL)
return -ENOMEM;
return 0;
}
return -ENOMEM;
}
int omap_vram_reserve(unsigned long paddr, size_t size)
{
unsigned pages;
int r;
DBG("reserve mem paddr %08lx size %d\n", paddr, size);
size = PAGE_ALIGN(size);
pages = size >> PAGE_SHIFT;
mutex_lock(&region_mutex);
r = _omap_vram_reserve(paddr, pages);
mutex_unlock(&region_mutex);
return r;
}
EXPORT_SYMBOL(omap_vram_reserve);
static void _omap_vram_dma_cb(int lch, u16 ch_status, void *data)
{
struct completion *compl = data;
complete(compl);
}
static int _omap_vram_clear(u32 paddr, unsigned pages)
{
struct completion compl;
unsigned elem_count;
unsigned frame_count;
int r;
int lch;
init_completion(&compl);
r = omap_request_dma(OMAP_DMA_NO_DEVICE, "VRAM DMA",
_omap_vram_dma_cb,
&compl, &lch);
if (r) {
pr_err("VRAM: request_dma failed for memory clear\n");
return -EBUSY;
}
elem_count = pages * PAGE_SIZE / 4;
frame_count = 1;
omap_set_dma_transfer_params(lch, OMAP_DMA_DATA_TYPE_S32,
elem_count, frame_count,
OMAP_DMA_SYNC_ELEMENT,
0, 0);
omap_set_dma_dest_params(lch, 0, OMAP_DMA_AMODE_POST_INC,
paddr, 0, 0);
omap_set_dma_color_mode(lch, OMAP_DMA_CONSTANT_FILL, 0x000000);
omap_start_dma(lch);
if (wait_for_completion_timeout(&compl, msecs_to_jiffies(1000)) == 0) {
omap_stop_dma(lch);
pr_err("VRAM: dma timeout while clearing memory\n");
r = -EIO;
goto err;
}
r = 0;
err:
omap_free_dma(lch);
return r;
}
static int _omap_vram_alloc(unsigned pages, unsigned long *paddr)
{
struct vram_region *rm;
struct vram_alloc *alloc;
list_for_each_entry(rm, &region_list, list) {
unsigned long start, end;
DBG("checking region %lx %d\n", rm->paddr, rm->pages);
start = rm->paddr;
list_for_each_entry(alloc, &rm->alloc_list, list) {
end = alloc->paddr;
if (end - start >= pages << PAGE_SHIFT)
goto found;
start = alloc->paddr + (alloc->pages << PAGE_SHIFT);
}
end = rm->paddr + (rm->pages << PAGE_SHIFT);
found:
if (end - start < pages << PAGE_SHIFT)
continue;
DBG("found %lx, end %lx\n", start, end);
alloc = omap_vram_create_allocation(rm, start, pages);
if (alloc == NULL)
return -ENOMEM;
*paddr = start;
_omap_vram_clear(start, pages);
return 0;
}
return -ENOMEM;
}
int omap_vram_alloc(size_t size, unsigned long *paddr)
{
unsigned pages;
int r;
BUG_ON(!size);
DBG("alloc mem size %d\n", size);
size = PAGE_ALIGN(size);
pages = size >> PAGE_SHIFT;
mutex_lock(&region_mutex);
r = _omap_vram_alloc(pages, paddr);
mutex_unlock(&region_mutex);
return r;
}
EXPORT_SYMBOL(omap_vram_alloc);
void omap_vram_get_info(unsigned long *vram,
unsigned long *free_vram,
unsigned long *largest_free_block)
{
struct vram_region *vr;
struct vram_alloc *va;
*vram = 0;
*free_vram = 0;
*largest_free_block = 0;
mutex_lock(&region_mutex);
list_for_each_entry(vr, &region_list, list) {
unsigned free;
unsigned long pa;
pa = vr->paddr;
*vram += vr->pages << PAGE_SHIFT;
list_for_each_entry(va, &vr->alloc_list, list) {
free = va->paddr - pa;
*free_vram += free;
if (free > *largest_free_block)
*largest_free_block = free;
pa = va->paddr + (va->pages << PAGE_SHIFT);
}
free = vr->paddr + (vr->pages << PAGE_SHIFT) - pa;
*free_vram += free;
if (free > *largest_free_block)
*largest_free_block = free;
}
mutex_unlock(&region_mutex);
}
EXPORT_SYMBOL(omap_vram_get_info);
#if defined(CONFIG_DEBUG_FS)
static int vram_debug_show(struct seq_file *s, void *unused)
{
struct vram_region *vr;
struct vram_alloc *va;
unsigned size;
mutex_lock(&region_mutex);
list_for_each_entry(vr, &region_list, list) {
size = vr->pages << PAGE_SHIFT;
seq_printf(s, "%08lx-%08lx (%d bytes)\n",
vr->paddr, vr->paddr + size - 1,
size);
list_for_each_entry(va, &vr->alloc_list, list) {
size = va->pages << PAGE_SHIFT;
seq_printf(s, " %08lx-%08lx (%d bytes)\n",
va->paddr, va->paddr + size - 1,
size);
}
}
mutex_unlock(&region_mutex);
return 0;
}
static int vram_debug_open(struct inode *inode, struct file *file)
{
return single_open(file, vram_debug_show, inode->i_private);
}
static const struct file_operations vram_debug_fops = {
.open = vram_debug_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init omap_vram_create_debugfs(void)
{
struct dentry *d;
d = debugfs_create_file("vram", S_IRUGO, NULL,
NULL, &vram_debug_fops);
if (IS_ERR(d))
return PTR_ERR(d);
return 0;
}
#endif
static __init int omap_vram_init(void)
{
int i;
vram_initialized = 1;
for (i = 0; i < postponed_cnt; i++)
omap_vram_add_region(postponed_regions[i].paddr,
postponed_regions[i].size);
#ifdef CONFIG_DEBUG_FS
if (omap_vram_create_debugfs())
pr_err("VRAM: Failed to create debugfs file\n");
#endif
return 0;
}
arch_initcall(omap_vram_init);
/* boottime vram alloc stuff */
/* set from board file */
static u32 omap_vram_sdram_start __initdata;
static u32 omap_vram_sdram_size __initdata;
/* set from kernel cmdline */
static u32 omap_vram_def_sdram_size __initdata;
static u32 omap_vram_def_sdram_start __initdata;
static int __init omap_vram_early_vram(char *p)
{
omap_vram_def_sdram_size = memparse(p, &p);
if (*p == ',')
omap_vram_def_sdram_start = simple_strtoul(p + 1, &p, 16);
return 0;
}
early_param("vram", omap_vram_early_vram);
/*
* Called from map_io. We need to call to this early enough so that we
* can reserve the fixed SDRAM regions before VM could get hold of them.
*/
void __init omap_vram_reserve_sdram_memblock(void)
{
u32 paddr;
u32 size = 0;
/* cmdline arg overrides the board file definition */
if (omap_vram_def_sdram_size) {
size = omap_vram_def_sdram_size;
paddr = omap_vram_def_sdram_start;
}
if (!size) {
size = omap_vram_sdram_size;
paddr = omap_vram_sdram_start;
}
#ifdef CONFIG_OMAP2_VRAM_SIZE
if (!size) {
size = CONFIG_OMAP2_VRAM_SIZE * 1024 * 1024;
paddr = 0;
}
#endif
if (!size)
return;
size = ALIGN(size, SZ_2M);
if (paddr) {
if (paddr & ~PAGE_MASK) {
pr_err("VRAM start address 0x%08x not page aligned\n",
paddr);
return;
}
if (!memblock_is_region_memory(paddr, size)) {
pr_err("Illegal SDRAM region 0x%08x..0x%08x for VRAM\n",
paddr, paddr + size - 1);
return;
}
if (memblock_is_region_reserved(paddr, size)) {
pr_err("FB: failed to reserve VRAM - busy\n");
return;
}
if (memblock_reserve(paddr, size) < 0) {
pr_err("FB: failed to reserve VRAM - no memory\n");
return;
}
} else {
paddr = memblock_alloc(size, SZ_2M);
}
memblock_free(paddr, size);
memblock_remove(paddr, size);
omap_vram_add_region(paddr, size);
pr_info("Reserving %u bytes SDRAM for VRAM\n", size);
}
void __init omap_vram_set_sdram_vram(u32 size, u32 start)
{
omap_vram_sdram_start = start;
omap_vram_sdram_size = size;
}