diff options
Diffstat (limited to 'drivers/gpu/vga/vga_switcheroo.c')
| -rw-r--r-- | drivers/gpu/vga/vga_switcheroo.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c new file mode 100644 index 00000000000..a3f587a0aba --- /dev/null +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -0,0 +1,453 @@ +/* + * Copyright (c) 2010 Red Hat Inc. + * Author : Dave Airlie <airlied@redhat.com> + * + * + * Licensed under GPLv2 + * + * vga_switcheroo.c - Support for laptop with dual GPU using one set of outputs + + Switcher interface - methods require for ATPX and DCM + - switchto - this throws the output MUX switch + - discrete_set_power - sets the power state for the discrete card + + GPU driver interface + - set_gpu_state - this should do the equiv of s/r for the card + - this should *not* set the discrete power state + - switch_check - check if the device is in a position to switch now + */ + +#include <linux/module.h> +#include <linux/dmi.h> +#include <linux/seq_file.h> +#include <linux/uaccess.h> +#include <linux/fs.h> +#include <linux/debugfs.h> +#include <linux/fb.h> + +#include <acpi/acpi.h> +#include <acpi/acpi_bus.h> + +#include <linux/pci.h> +#include <linux/vga_switcheroo.h> + +struct vga_switcheroo_client { + struct pci_dev *pdev; + struct fb_info *fb_info; + int pwr_state; + void (*set_gpu_state)(struct pci_dev *pdev, enum vga_switcheroo_state); + bool (*can_switch)(struct pci_dev *pdev); + int id; + bool active; +}; + +static DEFINE_MUTEX(vgasr_mutex); + +struct vgasr_priv { + + bool active; + bool delayed_switch_active; + enum vga_switcheroo_client_id delayed_client_id; + + struct dentry *debugfs_root; + struct dentry *switch_file; + + int registered_clients; + struct vga_switcheroo_client clients[VGA_SWITCHEROO_MAX_CLIENTS]; + + struct vga_switcheroo_handler *handler; +}; + +static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv); +static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv); + +/* only one switcheroo per system */ +static struct vgasr_priv vgasr_priv; + +int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler) +{ + mutex_lock(&vgasr_mutex); + if (vgasr_priv.handler) { + mutex_unlock(&vgasr_mutex); + return -EINVAL; + } + + vgasr_priv.handler = handler; + mutex_unlock(&vgasr_mutex); + return 0; +} +EXPORT_SYMBOL(vga_switcheroo_register_handler); + +void vga_switcheroo_unregister_handler(void) +{ + mutex_lock(&vgasr_mutex); + vgasr_priv.handler = NULL; + mutex_unlock(&vgasr_mutex); +} +EXPORT_SYMBOL(vga_switcheroo_unregister_handler); + +static void vga_switcheroo_enable(void) +{ + int i; + int ret; + /* call the handler to init */ + vgasr_priv.handler->init(); + + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + ret = vgasr_priv.handler->get_client_id(vgasr_priv.clients[i].pdev); + if (ret < 0) + return; + + vgasr_priv.clients[i].id = ret; + } + vga_switcheroo_debugfs_init(&vgasr_priv); + vgasr_priv.active = true; +} + +int vga_switcheroo_register_client(struct pci_dev *pdev, + void (*set_gpu_state)(struct pci_dev *pdev, enum vga_switcheroo_state), + bool (*can_switch)(struct pci_dev *pdev)) +{ + int index; + + mutex_lock(&vgasr_mutex); + /* don't do IGD vs DIS here */ + if (vgasr_priv.registered_clients & 1) + index = 1; + else + index = 0; + + vgasr_priv.clients[index].pwr_state = VGA_SWITCHEROO_ON; + vgasr_priv.clients[index].pdev = pdev; + vgasr_priv.clients[index].set_gpu_state = set_gpu_state; + vgasr_priv.clients[index].can_switch = can_switch; + vgasr_priv.clients[index].id = -1; + if (pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW) + vgasr_priv.clients[index].active = true; + + vgasr_priv.registered_clients |= (1 << index); + + /* if we get two clients + handler */ + if (vgasr_priv.registered_clients == 0x3 && vgasr_priv.handler) { + printk(KERN_INFO "vga_switcheroo: enabled\n"); + vga_switcheroo_enable(); + } + mutex_unlock(&vgasr_mutex); + return 0; +} +EXPORT_SYMBOL(vga_switcheroo_register_client); + +void vga_switcheroo_unregister_client(struct pci_dev *pdev) +{ + int i; + + mutex_lock(&vgasr_mutex); + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].pdev == pdev) { + vgasr_priv.registered_clients &= ~(1 << i); + break; + } + } + + printk(KERN_INFO "vga_switcheroo: disabled\n"); + vga_switcheroo_debugfs_fini(&vgasr_priv); + vgasr_priv.active = false; + mutex_unlock(&vgasr_mutex); +} +EXPORT_SYMBOL(vga_switcheroo_unregister_client); + +void vga_switcheroo_client_fb_set(struct pci_dev *pdev, + struct fb_info *info) +{ + int i; + + mutex_lock(&vgasr_mutex); + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].pdev == pdev) { + vgasr_priv.clients[i].fb_info = info; + break; + } + } + mutex_unlock(&vgasr_mutex); +} +EXPORT_SYMBOL(vga_switcheroo_client_fb_set); + +static int vga_switcheroo_show(struct seq_file *m, void *v) +{ + int i; + mutex_lock(&vgasr_mutex); + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + seq_printf(m, "%d:%c:%s:%s\n", i, + vgasr_priv.clients[i].active ? '+' : ' ', + vgasr_priv.clients[i].pwr_state ? "Pwr" : "Off", + pci_name(vgasr_priv.clients[i].pdev)); + } + mutex_unlock(&vgasr_mutex); + return 0; +} + +static int vga_switcheroo_debugfs_open(struct inode *inode, struct file *file) +{ + return single_open(file, vga_switcheroo_show, NULL); +} + +static int vga_switchon(struct vga_switcheroo_client *client) +{ + int ret; + + ret = vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_ON); + /* call the driver callback to turn on device */ + client->set_gpu_state(client->pdev, VGA_SWITCHEROO_ON); + client->pwr_state = VGA_SWITCHEROO_ON; + return 0; +} + +static int vga_switchoff(struct vga_switcheroo_client *client) +{ + /* call the driver callback to turn off device */ + client->set_gpu_state(client->pdev, VGA_SWITCHEROO_OFF); + vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_OFF); + client->pwr_state = VGA_SWITCHEROO_OFF; + return 0; +} + +static int vga_switchto(struct vga_switcheroo_client *new_client) +{ + int ret; + int i; + struct vga_switcheroo_client *active = NULL; + + if (new_client->active == true) + return 0; + + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].active == true) { + active = &vgasr_priv.clients[i]; + break; + } + } + if (!active) + return 0; + + /* power up the first device */ + ret = pci_enable_device(new_client->pdev); + if (ret) + return ret; + + if (new_client->pwr_state == VGA_SWITCHEROO_OFF) + vga_switchon(new_client); + + /* swap shadow resource to denote boot VGA device has changed so X starts on new device */ + active->active = false; + + active->pdev->resource[PCI_ROM_RESOURCE].flags &= ~IORESOURCE_ROM_SHADOW; + new_client->pdev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_SHADOW; + + if (new_client->fb_info) { + struct fb_event event; + event.info = new_client->fb_info; + fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event); + } + + ret = vgasr_priv.handler->switchto(new_client->id); + if (ret) + return ret; + + if (active->pwr_state == VGA_SWITCHEROO_ON) + vga_switchoff(active); + + new_client->active = true; + return 0; +} + +static ssize_t +vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char usercmd[64]; + const char *pdev_name; + int i, ret; + bool delay = false, can_switch; + int client_id = -1; + struct vga_switcheroo_client *client = NULL; + + if (cnt > 63) + cnt = 63; + + if (copy_from_user(usercmd, ubuf, cnt)) + return -EFAULT; + + mutex_lock(&vgasr_mutex); + + if (!vgasr_priv.active) + return -EINVAL; + + /* pwr off the device not in use */ + if (strncmp(usercmd, "OFF", 3) == 0) { + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].active) + continue; + if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_ON) + vga_switchoff(&vgasr_priv.clients[i]); + } + goto out; + } + /* pwr on the device not in use */ + if (strncmp(usercmd, "ON", 2) == 0) { + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].active) + continue; + if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_OFF) + vga_switchon(&vgasr_priv.clients[i]); + } + goto out; + } + + /* request a delayed switch - test can we switch now */ + if (strncmp(usercmd, "DIGD", 4) == 0) { + client_id = VGA_SWITCHEROO_IGD; + delay = true; + } + + if (strncmp(usercmd, "DDIS", 4) == 0) { + client_id = VGA_SWITCHEROO_DIS; + delay = true; + } + + if (strncmp(usercmd, "IGD", 3) == 0) + client_id = VGA_SWITCHEROO_IGD; + + if (strncmp(usercmd, "DIS", 3) == 0) + client_id = VGA_SWITCHEROO_DIS; + + if (client_id == -1) + goto out; + + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].id == client_id) { + client = &vgasr_priv.clients[i]; + break; + } + } + + vgasr_priv.delayed_switch_active = false; + /* okay we want a switch - test if devices are willing to switch */ + can_switch = true; + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev); + if (can_switch == false) { + printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i); + break; + } + } + + if (can_switch == false && delay == false) + goto out; + + if (can_switch == true) { + pdev_name = pci_name(client->pdev); + ret = vga_switchto(client); + if (ret) + printk(KERN_ERR "vga_switcheroo: switching failed %d\n", ret); + } else { + printk(KERN_INFO "vga_switcheroo: setting delayed switch to client %d\n", client->id); + vgasr_priv.delayed_switch_active = true; + vgasr_priv.delayed_client_id = client_id; + + /* we should at least power up the card to + make the switch faster */ + if (client->pwr_state == VGA_SWITCHEROO_OFF) + vga_switchon(client); + } + +out: + mutex_unlock(&vgasr_mutex); + return cnt; +} + +static const struct file_operations vga_switcheroo_debugfs_fops = { + .owner = THIS_MODULE, + .open = vga_switcheroo_debugfs_open, + .write = vga_switcheroo_debugfs_write, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv) +{ + if (priv->switch_file) { + debugfs_remove(priv->switch_file); + priv->switch_file = NULL; + } + if (priv->debugfs_root) { + debugfs_remove(priv->debugfs_root); + priv->debugfs_root = NULL; + } +} + +static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv) +{ + /* already initialised */ + if (priv->debugfs_root) + return 0; + priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL); + + if (!priv->debugfs_root) { + printk(KERN_ERR "vga_switcheroo: Cannot create /sys/kernel/debug/vgaswitcheroo\n"); + goto fail; + } + + priv->switch_file = debugfs_create_file("switch", 0644, + priv->debugfs_root, NULL, &vga_switcheroo_debugfs_fops); + if (!priv->switch_file) { + printk(KERN_ERR "vga_switcheroo: cannot create /sys/kernel/debug/vgaswitcheroo/switch\n"); + goto fail; + } + return 0; +fail: + vga_switcheroo_debugfs_fini(priv); + return -1; +} + +int vga_switcheroo_process_delayed_switch(void) +{ + struct vga_switcheroo_client *client = NULL; + const char *pdev_name; + bool can_switch = true; + int i; + int ret; + int err = -EINVAL; + + mutex_lock(&vgasr_mutex); + if (!vgasr_priv.delayed_switch_active) + goto err; + + printk(KERN_INFO "vga_switcheroo: processing delayed switch to %d\n", vgasr_priv.delayed_client_id); + + for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) { + if (vgasr_priv.clients[i].id == vgasr_priv.delayed_client_id) + client = &vgasr_priv.clients[i]; + can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev); + if (can_switch == false) { + printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i); + break; + } + } + + if (can_switch == false || client == NULL) + goto err; + + pdev_name = pci_name(client->pdev); + ret = vga_switchto(client); + if (ret) + printk(KERN_ERR "vga_switcheroo: delayed switching failed %d\n", ret); + + vgasr_priv.delayed_switch_active = false; + err = 0; +err: + mutex_unlock(&vgasr_mutex); + return err; +} +EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch); + |