Add a command line option in order to allow the user to provide a perferred
GPU at boot time.
Signed-off-by: Matthew Garrett <matthew.garrett at nebula.com>
---
Documentation/kernel-parameters.txt | 5 +++++
drivers/gpu/vga/vga_switcheroo.c | 29 +++++++++++++++++++++++++++++
2 files changed, 34 insertions(+)
diff --git a/Documentation/kernel-parameters.txt
b/Documentation/kernel-parameters.txt
index 30a8ad0d..6e6d505 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3486,6 +3486,11 @@ bytes respectively. Such letter suffixes can also be
entirely omitted.
This is actually a boot loader parameter; the value is
passed to the kernel using a special protocol.
+ vga_switcheroo= [HW] Switches the enabled GPU at boot time.
+ Format: { IGD | DIS }
+ IGD -- enable the Integrated GPU
+ DIS -- enable the Discrete GPU
+
vmalloc=nn[KMG] [KNL,BOOT] Forces the vmalloc area to have an exact
size of <nn>. This can be used to increase the
minimum size (128MB on x86). It can also be used to
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index c06ad5f..6d95626 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -67,6 +67,11 @@ struct vgasr_priv {
static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv);
static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv);
+static enum vga_switcheroo_client_id vga_switcheroo_default = -1;
+
+static int vga_switchto_stage1(struct vga_switcheroo_client *new_client);
+static int vga_switchto_stage2(struct vga_switcheroo_client *new_client);
+
/* only one switcheroo per system */
static struct vgasr_priv vgasr_priv = {
.clients = LIST_HEAD_INIT(vgasr_priv.clients),
@@ -107,6 +112,18 @@ static void vga_switcheroo_enable(void)
vgasr_priv.handler->switch_ddc(old_id);
}
}
+
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (!client->active && client->id == vga_switcheroo_default) {
+ ret = vga_switchto_stage1(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: switching
failed stage 1 %d\n", ret);
+
+ ret = vga_switchto_stage2(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: switching
failed stage 2 %d\n", ret);
+ }
+ }
vga_switcheroo_debugfs_init(&vgasr_priv);
vgasr_priv.active = true;
}
@@ -748,3 +765,15 @@ int
vga_switcheroo_init_domain_pm_optimus_hdmi_audio(struct device *dev, struct
return -EINVAL;
}
EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_optimus_hdmi_audio);
+
+static int __init vga_switcheroo_setup(char *str)
+{
+ if (!strcmp(str, "IGD"))
+ vga_switcheroo_default = VGA_SWITCHEROO_IGD;
+ else if (!strcmp(str, "DIS"))
+ vga_switcheroo_default = VGA_SWITCHEROO_DIS;
+
+ return 1;
+}
+
+__setup("vga_switcheroo=", vga_switcheroo_setup);
--
1.8.5.3
