[RFC PATCH 7/7] drm/pci: Defer initialization of secondary graphics devices until switcheroo is ready
Seth Forshee
seth.forshee at canonical.com
Mon Aug 20 08:31:04 PDT 2012
Deferring initiailzation of the secondary GPU until switcheroo is ready
will allow successfully reading the EDID in systems which support muxing
the DDC seperately from the display.
Signed-off-by: Seth Forshee <seth.forshee at canonical.com>
---
drivers/gpu/drm/drm_drv.c | 3 +
drivers/gpu/drm/drm_pci.c | 141 +++++++++++++++++++++++++++++++++++++++------
include/drm/drmP.h | 2 +
3 files changed, 129 insertions(+), 17 deletions(-)
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 9238de4..124fd8a 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -276,6 +276,8 @@ static int __init drm_core_init(void)
goto err_p3;
}
+ drm_pci_module_init();
+
DRM_INFO("Initialized %s %d.%d.%d %s\n",
CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
return 0;
@@ -291,6 +293,7 @@ err_p1:
static void __exit drm_core_exit(void)
{
+ drm_pci_module_exit();
remove_proc_entry("dri", NULL);
debugfs_remove(drm_debugfs_root);
drm_sysfs_destroy();
diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c
index 4896c96..9da0cd2 100644
--- a/drivers/gpu/drm/drm_pci.c
+++ b/drivers/gpu/drm/drm_pci.c
@@ -40,6 +40,9 @@
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
+#include <linux/notifier.h>
+#include <linux/vgaarb.h>
+#include <linux/vga_switcheroo.h>
#include "drmP.h"
/**********************************************************************/
@@ -297,19 +300,8 @@ static struct drm_bus drm_pci_bus = {
.agp_init = drm_pci_agp_init,
};
-/**
- * Register.
- *
- * \param pdev - PCI device structure
- * \param ent entry from the PCI ID table with device type flags
- * \return zero on success or a negative number on failure.
- *
- * Attempt to gets inter module "drm" information. If we are first
- * then register the character device and inter module information.
- * Try and register, if we fail to register, backout previous work.
- */
-int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
- struct drm_driver *driver)
+int __drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
+ struct drm_driver *driver)
{
struct drm_device *dev;
int ret;
@@ -334,8 +326,6 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
dev->hose = pdev->sysdata;
#endif
- mutex_lock(&drm_global_mutex);
-
if ((ret = drm_fill_in_dev(dev, ent, driver))) {
printk(KERN_ERR "DRM: Fill_in_dev failed.\n");
goto err_g2;
@@ -371,7 +361,6 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
driver->name, driver->major, driver->minor, driver->patchlevel,
driver->date, pci_name(pdev), dev->primary->index);
- mutex_unlock(&drm_global_mutex);
return 0;
err_g4:
@@ -386,10 +375,116 @@ err_g1:
mutex_unlock(&drm_global_mutex);
return ret;
}
+
+struct deferred_init_data {
+ struct list_head list;
+ struct pci_dev *pdev;
+ const struct pci_device_id *ent;
+ struct drm_driver *driver;
+};
+
+static LIST_HEAD(deferred_init_list);
+
+static void drm_deferred_init_work_fn(struct work_struct *work)
+{
+ struct deferred_init_data *di_data, *temp;
+
+ mutex_lock(&drm_global_mutex);
+
+ if (!vga_switcheroo_handler_registered() ||
+ !vga_switcheroo_get_active_client()) {
+ mutex_unlock(&drm_global_mutex);
+ return;
+ }
+
+ list_for_each_entry_safe(di_data, temp, &deferred_init_list, list) {
+ if (__drm_get_pci_dev(di_data->pdev, di_data->ent,
+ di_data->driver))
+ DRM_ERROR("pci device initialization failed\n");
+ list_del(&di_data->list);
+ kfree(di_data);
+ }
+ mutex_unlock(&drm_global_mutex);
+}
+static DECLARE_WORK(deferred_init_work, drm_deferred_init_work_fn);
+
+static int drm_switcheroo_notifier_fn(struct notifier_block *nb,
+ unsigned long val, void *unused)
+{
+ if (val == VGA_SWITCHEROO_CLIENT_REGISTERED ||
+ val == VGA_SWITCHEROO_HANDLER_REGISTERED)
+ queue_work(system_nrt_wq, &deferred_init_work);
+ return NOTIFY_OK;
+}
+static struct notifier_block drm_switcheroo_notifier = {
+ .notifier_call = drm_switcheroo_notifier_fn,
+};
+
+/**
+ * Register.
+ *
+ * \param pdev - PCI device structure
+ * \param ent entry from the PCI ID table with device type flags
+ * \return zero on success or a negative number on failure.
+ *
+ * Attempt to gets inter module "drm" information. If we are first
+ * then register the character device and inter module information.
+ * Try and register, if we fail to register, backout previous work.
+ */
+int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent,
+ struct drm_driver *driver)
+{
+ int ret = 0;
+
+ mutex_lock(&drm_global_mutex);
+
+ /*
+ * For secondary graphics devices shouldn't be initialized
+ * until the handler and primary graphics device have been
+ * registered with vga_switcheroo.
+ *
+ * FIXME: Is vga_default_device() reliable enough for this
+ * purpose?
+ *
+ * FIXME: If vga_switcheroo is disabled secondary devices
+ * never gets initialized. Is this okay? Maybe it is, since
+ * we can't switch to the secondary GPU anyway.
+ */
+ if (vga_default_device() == pdev ||
+ (vga_switcheroo_handler_registered() &&
+ vga_switcheroo_get_active_client())) {
+ ret = __drm_get_pci_dev(pdev, ent, driver);
+ } else {
+ struct deferred_init_data *di_data =
+ kmalloc(sizeof(*di_data), GFP_KERNEL);
+ if (!di_data) {
+ ret = -ENOMEM;
+ } else {
+ di_data->pdev = pdev;
+ di_data->ent = ent;
+ di_data->driver = driver;
+ list_add_tail(&di_data->list, &deferred_init_list);
+ }
+ }
+
+ return ret;
+}
EXPORT_SYMBOL(drm_get_pci_dev);
void drm_put_pci_dev(struct drm_device *dev)
{
+ struct deferred_init_data *di_data;
+
+ mutex_lock(&drm_global_mutex);
+ list_for_each_entry(di_data, &deferred_init_list, list) {
+ if (di_data->pdev == dev->pdev) {
+ list_del(&di_data->list);
+ kfree(di_data);
+ break;
+ }
+ }
+ mutex_unlock(&drm_global_mutex);
+
drm_put_dev(dev);
}
EXPORT_SYMBOL(drm_put_pci_dev);
@@ -466,7 +561,7 @@ void drm_pci_exit(struct drm_driver *driver, struct pci_driver *pdriver)
pci_unregister_driver(pdriver);
} else {
list_for_each_entry_safe(dev, tmp, &driver->device_list, driver_item)
- drm_put_dev(dev);
+ drm_put_pci_dev(dev);
}
DRM_INFO("Module unloaded\n");
}
@@ -520,3 +615,15 @@ int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *mask)
return 0;
}
EXPORT_SYMBOL(drm_pcie_get_speed_cap_mask);
+
+int drm_pci_module_init(void)
+{
+ return vga_switcheroo_register_notifier(&drm_switcheroo_notifier);
+}
+EXPORT_SYMBOL(drm_pci_module_init);
+
+void drm_pci_module_exit(void)
+{
+ vga_switcheroo_unregister_notifier(&drm_switcheroo_notifier);
+}
+EXPORT_SYMBOL(drm_pci_module_exit);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index eb99e96..0e9401f 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1749,6 +1749,8 @@ extern int drm_get_pci_dev(struct pci_dev *pdev,
const struct pci_device_id *ent,
struct drm_driver *driver);
extern void drm_put_pci_dev(struct drm_device *dev);
+extern int drm_pci_module_init(void);
+extern void drm_pci_module_exit(void);
#define DRM_PCIE_SPEED_25 1
#define DRM_PCIE_SPEED_50 2
--
1.7.9.5
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