[patch 2.6.10-rc3 1/4] agpgart: allow multiple backends to be initialized

From: Mike Werner
Date: Fri Dec 17 2004 - 16:07:21 EST

This new version reduces the number of changes required by users of the agpgart
such as drm to support the new api for multiple agp bridges.
The first patch doesn't touch any platform specific files and all current platform
gart drivers will just work the same as they do now since the global
agp_bridge is still supported as the default bridge.

Summary for the 4 patches.
[1/4] Allow multiple backends to be initialized for agpgart
[2/4] Run Lindent on generic.c
[3/4] Patch drm code to work with modified agpgart api.
[4/4] Patch framebuffer code to work with modified agpgart api.
-----------------------------------------------------------------------------
drivers/char/agp/agp.h | 3 +
drivers/char/agp/backend.c | 112 +++++++++++++++++++++++++-------------------
drivers/char/agp/frontend.c | 30 ++++++-----
drivers/char/agp/generic.c | 71 ++++++++++++++++-----------
include/linux/agp_backend.h | 32 +++++++-----
5 files changed, 145 insertions(+), 103 deletions(-)

# This is a BitKeeper generated diff -Nru style patch.
#
# Allow multiple backends to be initialized
#
diff -Nru a/drivers/char/agp/agp.h b/drivers/char/agp/agp.h
--- a/drivers/char/agp/agp.h 2004-12-17 10:36:04 -08:00
+++ b/drivers/char/agp/agp.h 2004-12-17 10:36:04 -08:00
@@ -1,5 +1,6 @@
/*
* AGPGART
+ * Copyright (C) 2004 Silicon Graphics, Inc.
* Copyright (C) 2002-2004 Dave Jones
* Copyright (C) 1999 Jeff Hartmann
* Copyright (C) 1999 Precision Insight, Inc.
@@ -139,6 +140,7 @@
int capndx;
char major_version;
char minor_version;
+ struct list_head list;
};

#define OUTREG64(mmap, addr, val) __raw_writeq((val), (mmap)+(addr))
@@ -271,6 +273,7 @@
void global_cache_flush(void);
void get_agp_version(struct agp_bridge_data *bridge);
unsigned long agp_generic_mask_memory(unsigned long addr, int type);
+struct agp_bridge_data *agp_generic_find_bridge(struct pci_dev *pdev);

/* generic routines for agp>=3 */
int agp3_generic_fetch_size(void);
diff -Nru a/drivers/char/agp/backend.c b/drivers/char/agp/backend.c
--- a/drivers/char/agp/backend.c 2004-12-17 10:36:04 -08:00
+++ b/drivers/char/agp/backend.c 2004-12-17 10:36:04 -08:00
@@ -1,5 +1,6 @@
/*
* AGPGART driver backend routines.
+ * Copyright (C) 2004 Silicon Graphics, Inc.
* Copyright (C) 2002-2003 Dave Jones.
* Copyright (C) 1999 Jeff Hartmann.
* Copyright (C) 1999 Precision Insight, Inc.
@@ -42,34 +43,36 @@
* fix some real stupidity. It's only by chance we can bump
* past 0.99 at all due to some boolean logic error. */
#define AGPGART_VERSION_MAJOR 0
-#define AGPGART_VERSION_MINOR 100
+#define AGPGART_VERSION_MINOR 101
static struct agp_version agp_current_version =
{
.major = AGPGART_VERSION_MAJOR,
.minor = AGPGART_VERSION_MINOR,
};

-static int agp_count=0;
-
-struct agp_bridge_data agp_bridge_dummy = { .type = NOT_SUPPORTED };
-struct agp_bridge_data *agp_bridge = &agp_bridge_dummy;
+struct agp_bridge_data *agp_bridge;
+LIST_HEAD(agp_bridges);
+struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *pdev);
EXPORT_SYMBOL(agp_bridge);
-
+EXPORT_SYMBOL(agp_bridges);

/**
- * agp_backend_acquire - attempt to acquire the agp backend.
+ * agp_backend_acquire - attempt to acquire an agp backend.
*
- * returns -EBUSY if agp is in use,
- * returns 0 if the caller owns the agp backend
*/
-int agp_backend_acquire(void)
+struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev)
{
- if (agp_bridge->type == NOT_SUPPORTED)
- return -EINVAL;
- if (atomic_read(&agp_bridge->agp_in_use))
- return -EBUSY;
- atomic_inc(&agp_bridge->agp_in_use);
- return 0;
+ struct agp_bridge_data *bridge;
+
+ bridge = agp_find_bridge(pdev);
+
+ if (!bridge)
+ return NULL;
+
+ if (atomic_read(&bridge->agp_in_use))
+ return NULL;
+ atomic_inc(&bridge->agp_in_use);
+ return bridge;
}
EXPORT_SYMBOL(agp_backend_acquire);

@@ -82,10 +85,11 @@
*
* (Ensure that all memory it bound is unbound.)
*/
-void agp_backend_release(void)
+void agp_backend_release(struct agp_bridge_data *bridge)
{
- if (agp_bridge->type != NOT_SUPPORTED)
- atomic_dec(&agp_bridge->agp_in_use);
+
+ if (bridge)
+ atomic_dec(&bridge->agp_in_use);
}
EXPORT_SYMBOL(agp_backend_release);

@@ -121,7 +125,6 @@
(maxes_table[index].agp - maxes_table[index - 1].agp)) /
(maxes_table[index].mem - maxes_table[index - 1].mem);

- printk(KERN_INFO PFX "Maximum main memory to use for agp memory: %ldM\n", result);
result = result << (20 - PAGE_SHIFT);
return result;
}
@@ -178,9 +181,6 @@
goto err_out;
}

- printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n",
- size_value, bridge->gart_bus_addr);
-
return 0;

err_out:
@@ -225,16 +225,31 @@
&agp_copy_info
};

-/* XXX Kludge alert: agpgart isn't ready for multiple bridges yet */
+/* When we remove the global variable agp_bridge from all drivers
+ * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
+ */
+
struct agp_bridge_data *agp_alloc_bridge(void)
{
- return agp_bridge;
+ struct agp_bridge_data *bridge = kmalloc(sizeof(*bridge), GFP_KERNEL);
+
+ if (!bridge)
+ return NULL;
+
+ if (list_empty(&agp_bridges))
+ agp_bridge = bridge;
+
+ return bridge;
}
EXPORT_SYMBOL(agp_alloc_bridge);


void agp_put_bridge(struct agp_bridge_data *bridge)
{
+ kfree(bridge);
+
+ if (list_empty(&agp_bridges))
+ agp_bridge = NULL;
}
EXPORT_SYMBOL(agp_put_bridge);

@@ -251,43 +266,41 @@
return -EINVAL;
}

- if (agp_count) {
- printk (KERN_INFO PFX
- "Only one agpgart device currently supported.\n");
- return -ENODEV;
- }
-
/* Grab reference on the chipset driver. */
if (!try_module_get(bridge->driver->owner)) {
printk (KERN_INFO PFX "Couldn't lock chipset driver.\n");
return -EINVAL;
}

- bridge->type = SUPPORTED;
-
- error = agp_backend_initialize(agp_bridge);
+ error = agp_backend_initialize(bridge);
if (error) {
printk (KERN_INFO PFX "agp_backend_initialize() failed.\n");
goto err_out;
}

- error = agp_frontend_initialize();
- if (error) {
- printk (KERN_INFO PFX "agp_frontend_initialize() failed.\n");
- goto frontend_err;
- }
+ if (list_empty(&agp_bridges)) {
+ error = agp_frontend_initialize();
+ if (error) {
+ printk (KERN_INFO PFX "agp_frontend_initialize() failed.\n");
+ goto frontend_err;
+ }
+
+ /* FIXME: What to do with this? */
+ inter_module_register("drm_agp", THIS_MODULE, &drm_agp);

- /* FIXME: What to do with this? */
- inter_module_register("drm_agp", THIS_MODULE, &drm_agp);
+ printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n",
+ bridge->driver->fetch_size(), bridge->gart_bus_addr);
+
+ }

- agp_count++;
+ list_add(&bridge->list, &agp_bridges);
return 0;

frontend_err:
- agp_backend_cleanup(agp_bridge);
+ agp_backend_cleanup(bridge);
err_out:
- bridge->type = NOT_SUPPORTED;
module_put(bridge->driver->owner);
+ agp_put_bridge(bridge);
return error;
}
EXPORT_SYMBOL_GPL(agp_add_bridge);
@@ -295,11 +308,12 @@

void agp_remove_bridge(struct agp_bridge_data *bridge)
{
- bridge->type = NOT_SUPPORTED;
- agp_frontend_cleanup();
agp_backend_cleanup(bridge);
- inter_module_unregister("drm_agp");
- agp_count--;
+ list_del(&bridge->list);
+ if (list_empty(&agp_bridges)) {
+ agp_frontend_cleanup();
+ inter_module_unregister("drm_agp");
+ }
module_put(bridge->driver->owner);
}
EXPORT_SYMBOL_GPL(agp_remove_bridge);
@@ -311,6 +325,8 @@

static int __init agp_init(void)
{
+ agp_find_bridge = &agp_generic_find_bridge;
+
if (!agp_off)
printk(KERN_INFO "Linux agpgart interface v%d.%d (c) Dave Jones\n",
AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);
diff -Nru a/drivers/char/agp/frontend.c b/drivers/char/agp/frontend.c
--- a/drivers/char/agp/frontend.c 2004-12-17 10:36:04 -08:00
+++ b/drivers/char/agp/frontend.c 2004-12-17 10:36:04 -08:00
@@ -1,5 +1,6 @@
/*
* AGPGART driver frontend
+ * Copyright (C) 2004 Silicon Graphics, Inc.
* Copyright (C) 2002-2003 Dave Jones
* Copyright (C) 1999 Jeff Hartmann
* Copyright (C) 1999 Precision Insight, Inc.
@@ -299,7 +300,7 @@
{
struct agp_memory *memory;

- memory = agp_allocate_memory(pg_count, type);
+ memory = agp_allocate_memory(agp_bridge, pg_count, type);
if (memory == NULL)
return NULL;

@@ -420,7 +421,7 @@
if (agp_fe.current_controller == controller) {
agp_fe.current_controller = NULL;
agp_fe.backend_acquired = FALSE;
- agp_backend_release();
+ agp_backend_release(agp_bridge);
}
kfree(controller);
return 0;
@@ -468,7 +469,7 @@

agp_fe.current_controller = NULL;
agp_fe.used_by_controller = FALSE;
- agp_backend_release();
+ agp_backend_release(agp_bridge);
}

/*
@@ -605,7 +606,7 @@
if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags)))
goto out_eperm;

- agp_copy_info(&kerninfo);
+ agp_copy_info(agp_bridge, &kerninfo);
size = vma->vm_end - vma->vm_start;
current_size = kerninfo.aper_size;
current_size = current_size * 0x100000;
@@ -757,7 +758,7 @@
struct agp_info userinfo;
struct agp_kern_info kerninfo;

- agp_copy_info(&kerninfo);
+ agp_copy_info(agp_bridge, &kerninfo);

userinfo.version.major = kerninfo.version.major;
userinfo.version.minor = kerninfo.version.minor;
@@ -777,7 +778,6 @@

static int agpioc_acquire_wrap(struct agp_file_private *priv)
{
- int ret;
struct agp_controller *controller;

DBG("");
@@ -788,11 +788,15 @@
if (agp_fe.current_controller != NULL)
return -EBUSY;

- ret = agp_backend_acquire();
- if (ret == 0)
- agp_fe.backend_acquired = TRUE;
- else
- return ret;
+ if(!agp_bridge)
+ return -ENODEV;
+
+ if (atomic_read(&agp_bridge->agp_in_use))
+ return -EBUSY;
+
+ atomic_inc(&agp_bridge->agp_in_use);
+
+ agp_fe.backend_acquired = TRUE;

controller = agp_find_controller_by_pid(priv->my_pid);

@@ -803,7 +807,7 @@

if (controller == NULL) {
agp_fe.backend_acquired = FALSE;
- agp_backend_release();
+ agp_backend_release(agp_bridge);
return -ENOMEM;
}
agp_insert_controller(controller);
@@ -830,7 +834,7 @@
if (copy_from_user(&mode, arg, sizeof(struct agp_setup)))
return -EFAULT;

- agp_enable(mode.agp_mode);
+ agp_enable(agp_bridge, mode.agp_mode);
return 0;
}

diff -Nru a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c
--- a/drivers/char/agp/generic.c 2004-12-17 10:36:04 -08:00
+++ b/drivers/char/agp/generic.c 2004-12-17 10:36:04 -08:00
@@ -1,5 +1,6 @@
/*
* AGPGART driver.
+ * Copyright (C) 2004 Silicon Graphics, Inc.
* Copyright (C) 2002-2004 Dave Jones.
* Copyright (C) 1999 Jeff Hartmann.
* Copyright (C) 1999 Precision Insight, Inc.
@@ -116,19 +117,19 @@
{
size_t i;

- if ((agp_bridge->type == NOT_SUPPORTED) || (curr == NULL))
+ if (curr == NULL)
return;

if (curr->is_bound == TRUE)
agp_unbind_memory(curr);

if (curr->type != 0) {
- agp_bridge->driver->free_by_type(curr);
+ curr->bridge->driver->free_by_type(curr);
return;
}
if (curr->page_count != 0) {
for (i = 0; i < curr->page_count; i++) {
- agp_bridge->driver->agp_destroy_page(phys_to_virt(curr->memory[i]));
+ curr->bridge->driver->agp_destroy_page(phys_to_virt(curr->memory[i]));
}
}
agp_free_key(curr->key);
@@ -150,20 +151,20 @@
*
* It returns NULL whenever memory is unavailable.
*/
-struct agp_memory *agp_allocate_memory(size_t page_count, u32 type)
+struct agp_memory *agp_allocate_memory(struct agp_bridge_data *bridge, size_t page_count, u32 type)
{
int scratch_pages;
struct agp_memory *new;
size_t i;

- if (agp_bridge->type == NOT_SUPPORTED)
+ if (!bridge)
return NULL;

- if ((atomic_read(&agp_bridge->current_memory_agp) + page_count) > agp_bridge->max_memory_agp)
+ if ((atomic_read(&bridge->current_memory_agp) + page_count) > bridge->max_memory_agp)
return NULL;

if (type != 0) {
- new = agp_bridge->driver->alloc_by_type(page_count, type);
+ new = bridge->driver->alloc_by_type(page_count, type);
return new;
}

@@ -175,14 +176,14 @@
return NULL;

for (i = 0; i < page_count; i++) {
- void *addr = agp_bridge->driver->agp_alloc_page();
+ void *addr = bridge->driver->agp_alloc_page();

if (addr == NULL) {
agp_free_memory(new);
return NULL;
}
new->memory[i] =
- agp_bridge->driver->mask_memory(virt_to_phys(addr), type);
+ bridge->driver->mask_memory(virt_to_phys(addr), type);
new->page_count++;
}

@@ -275,26 +276,25 @@
* This function copies information about the agp bridge device and the state of
* the agp backend into an agp_kern_info pointer.
*/
-int agp_copy_info(struct agp_kern_info *info)
+int agp_copy_info(struct agp_bridge_data *bridge, struct agp_kern_info *info)
{
memset(info, 0, sizeof(struct agp_kern_info));
- if (!agp_bridge || agp_bridge->type == NOT_SUPPORTED ||
- !agp_bridge->version) {
+ if (!bridge) {
info->chipset = NOT_SUPPORTED;
return -EIO;
}

- info->version.major = agp_bridge->version->major;
- info->version.minor = agp_bridge->version->minor;
- info->chipset = agp_bridge->type;
- info->device = agp_bridge->dev;
- info->mode = agp_bridge->mode;
- info->aper_base = agp_bridge->gart_bus_addr;
+ info->version.major = bridge->version->major;
+ info->version.minor = bridge->version->minor;
+ info->chipset = SUPPORTED;
+ info->device = bridge->dev;
+ info->mode = bridge->mode;
+ info->aper_base = bridge->gart_bus_addr;
info->aper_size = agp_return_size();
- info->max_memory = agp_bridge->max_memory_agp;
- info->current_memory = atomic_read(&agp_bridge->current_memory_agp);
- info->cant_use_aperture = agp_bridge->driver->cant_use_aperture;
- info->vm_ops = agp_bridge->vm_ops;
+ info->max_memory = bridge->max_memory_agp;
+ info->current_memory = atomic_read(&bridge->current_memory_agp);
+ info->cant_use_aperture = bridge->driver->cant_use_aperture;
+ info->vm_ops = bridge->vm_ops;
info->page_mask = ~0UL;
return 0;
}
@@ -323,7 +323,7 @@
{
int ret_val;

- if ((agp_bridge->type == NOT_SUPPORTED) || (curr == NULL))
+ if (curr == NULL)
return -EINVAL;

if (curr->is_bound == TRUE) {
@@ -331,10 +331,10 @@
return -EINVAL;
}
if (curr->is_flushed == FALSE) {
- agp_bridge->driver->cache_flush();
+ curr->bridge->driver->cache_flush();
curr->is_flushed = TRUE;
}
- ret_val = agp_bridge->driver->insert_memory(curr, pg_start, curr->type);
+ ret_val = curr->bridge->driver->insert_memory(curr, pg_start, curr->type);

if (ret_val != 0)
return ret_val;
@@ -358,7 +358,7 @@
{
int ret_val;

- if ((agp_bridge->type == NOT_SUPPORTED) || (curr == NULL))
+ if (curr == NULL)
return -EINVAL;

if (curr->is_bound != TRUE) {
@@ -366,7 +366,7 @@
return -EINVAL;
}

- ret_val = agp_bridge->driver->remove_memory(curr, curr->pg_start, curr->type);
+ ret_val = curr->bridge->driver->remove_memory(curr, curr->pg_start, curr->type);

if (ret_val != 0)
return ret_val;
@@ -949,14 +949,25 @@
*
* @mode: agp mode register value to configure with.
*/
-void agp_enable(u32 mode)
+void agp_enable(struct agp_bridge_data *bridge, u32 mode)
{
- if (agp_bridge->type == NOT_SUPPORTED)
+ if (!bridge)
return;
- agp_bridge->driver->agp_enable(mode);
+ bridge->driver->agp_enable(mode);
}
EXPORT_SYMBOL(agp_enable);

+/* When we remove the global variable agp_bridge from all drivers
+ * then agp_alloc_bridge and agp_generic_find_bridge need to be updated
+ */
+
+struct agp_bridge_data *agp_generic_find_bridge(struct pci_dev *pdev)
+{
+ if (list_empty(&agp_bridges))
+ return NULL;
+
+ return agp_bridge;
+}

#ifdef CONFIG_SMP
static void ipi_handler(void *null)
diff -Nru a/include/linux/agp_backend.h b/include/linux/agp_backend.h
--- a/include/linux/agp_backend.h 2004-12-17 10:36:04 -08:00
+++ b/include/linux/agp_backend.h 2004-12-17 10:36:04 -08:00
@@ -1,6 +1,7 @@
/*
* AGPGART backend specific includes. Not for userspace consumption.
*
+ * Copyright (C) 2004 Silicon Graphics, Inc.
* Copyright (C) 2002-2003 Dave Jones
* Copyright (C) 1999 Jeff Hartmann
* Copyright (C) 1999 Precision Insight, Inc.
@@ -71,13 +72,16 @@
* the items to detrimine the status of this block of agp memory.
*/

+struct agp_bridge_data;
+
struct agp_memory {
- int key;
struct agp_memory *next;
struct agp_memory *prev;
+ struct agp_bridge_data *bridge;
+ unsigned long *memory;
size_t page_count;
+ int key;
int num_scratch_pages;
- unsigned long *memory;
off_t pg_start;
u32 type;
u32 physical;
@@ -87,14 +91,18 @@

#define AGP_NORMAL_MEMORY 0

+extern struct agp_bridge_data *agp_bridge;
+extern struct list_head agp_bridges;
+extern struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *);
+
extern void agp_free_memory(struct agp_memory *);
-extern struct agp_memory *agp_allocate_memory(size_t, u32);
-extern int agp_copy_info(struct agp_kern_info *);
+extern struct agp_memory *agp_allocate_memory(struct agp_bridge_data *, size_t, u32);
+extern int agp_copy_info(struct agp_bridge_data *, struct agp_kern_info *);
extern int agp_bind_memory(struct agp_memory *, off_t);
extern int agp_unbind_memory(struct agp_memory *);
-extern void agp_enable(u32);
-extern int agp_backend_acquire(void);
-extern void agp_backend_release(void);
+extern void agp_enable(struct agp_bridge_data *, u32);
+extern struct agp_bridge_data *agp_backend_acquire(struct pci_dev *);
+extern void agp_backend_release(struct agp_bridge_data *);

/*
* Interface between drm and agp code. When agp initializes, it makes
@@ -103,13 +111,13 @@
*/
typedef struct {
void (*free_memory)(struct agp_memory *);
- struct agp_memory * (*allocate_memory)(size_t, u32);
+ struct agp_memory * (*allocate_memory)(struct agp_bridge_data *, size_t, u32);
int (*bind_memory)(struct agp_memory *, off_t);
int (*unbind_memory)(struct agp_memory *);
- void (*enable)(u32);
- int (*acquire)(void);
- void (*release)(void);
- int (*copy_info)(struct agp_kern_info *);
+ void (*enable)(struct agp_bridge_data *, u32);
+ struct agp_bridge_data *(*acquire)(struct pci_dev *);
+ void (*release)(struct agp_bridge_data *);
+ int (*copy_info)(struct agp_bridge_data *, struct agp_kern_info *);
} drm_agp_t;

extern const drm_agp_t *drm_agp_p;
-
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