vga_switcheroo: initial implementation (v15)
Many new laptops now come with 2 gpus, one to be used for low power
modes and one for gaming/on-ac applications. These GPUs are typically
wired to the laptop panel and VGA ports via a multiplexer unit which
is controlled via ACPI methods.
4 combinations of systems typically exist - with 2 ACPI methods.
Intel/ATI - Lenovo W500/T500 - use ATPX ACPI method
ATI/ATI - some ASUS - use ATPX ACPI Method
Intel/Nvidia - - use _DSM ACPI method
Nvidia/Nvidia - - use _DSM ACPI method.
TODO:
This patch adds support for the ATPX method and initial bits
for the _DSM methods that need to written by someone with
access to the hardware.
Add a proper non-debugfs interface - need to get some proper
testing first.
v2: add power up/down support for both devices
on W500 puts i915/radeon into D3 and cuts power to radeon.
v3: redo probing methods, no DMI list, drm devices call to
register with switcheroo, it tries to find an ATPX method on
any device and once there is two devices + ATPX it inits the
switcher.
v4: ATPX msg handling using buffers - should work on more machines
v5: rearchitect after more mjg59 discussion - move ATPX handling to
radeon driver.
v6: add file headers + initial nouveau bits (to be filled out).
v7: merge delayed switcher code.
v8: avoid suspend/resume of gpu that is off
v9: rearchitect - mjg59 is always right. - move all ATPX code to
radeon, should allow simpler DSM also proper ATRM handling
v10: add ATRM support for radeon BIOS, add mutex to lock vgasr_priv
v11: fix bug in resuming Intel for 2nd time.
v12: start fixing up nvidia code blindly.
v13: blindly guess at finishing nvidia code
v14: remove radeon audio hacks - fix up intel resume more like upstream
v15: clean up printks + remove unnecessary igd/dis pointers
mount debugfs
/sys/kernel/debug/vgaswitcheroo/switch - should exist if ATPX detected
+ 2 cards.
DIS - immediate change to discrete
IGD - immediate change to IGD
DDIS - delayed change to discrete
DIGD - delayed change to IGD
ON - turn on not in use
OFF - turn off not in use
Tested on W500 (Intel/ATI) and T500 (Intel/ATI)
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 2307f98..42ca07f 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -35,6 +35,7 @@
#include "i915_drv.h"
#include "i915_trace.h"
#include <linux/vgaarb.h>
+#include <linux/vga_switcheroo.h>
/* Really want an OS-independent resettable timer. Would like to have
* this loop run for (eg) 3 sec, but have the timer reset every time
@@ -1199,6 +1200,32 @@
return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
}
+static void i915_switcheroo_set_state(struct pci_dev *pdev, enum vga_switcheroo_state state)
+{
+ struct drm_device *dev = pci_get_drvdata(pdev);
+ pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
+ if (state == VGA_SWITCHEROO_ON) {
+ printk(KERN_INFO "i915: switched off\n");
+ /* i915 resume handler doesn't set to D0 */
+ pci_set_power_state(dev->pdev, PCI_D0);
+ i915_resume(dev);
+ } else {
+ printk(KERN_ERR "i915: switched off\n");
+ i915_suspend(dev, pmm);
+ }
+}
+
+static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
+{
+ struct drm_device *dev = pci_get_drvdata(pdev);
+ bool can_switch;
+
+ spin_lock(&dev->count_lock);
+ can_switch = (dev->open_count == 0);
+ spin_unlock(&dev->count_lock);
+ return can_switch;
+}
+
static int i915_load_modeset_init(struct drm_device *dev,
unsigned long prealloc_start,
unsigned long prealloc_size,
@@ -1260,6 +1287,12 @@
if (ret)
goto destroy_ringbuffer;
+ ret = vga_switcheroo_register_client(dev->pdev,
+ i915_switcheroo_set_state,
+ i915_switcheroo_can_switch);
+ if (ret)
+ goto destroy_ringbuffer;
+
intel_modeset_init(dev);
ret = drm_irq_install(dev);
@@ -1544,6 +1577,7 @@
dev_priv->child_dev_num = 0;
}
drm_irq_uninstall(dev);
+ vga_switcheroo_unregister_client(dev->pdev);
vga_client_register(dev->pdev, NULL, NULL, NULL);
}
@@ -1611,6 +1645,7 @@
if (!dev_priv || drm_core_check_feature(dev, DRIVER_MODESET)) {
drm_fb_helper_restore();
+ vga_switcheroo_process_delayed_switch();
return;
}