1 files changed, 399 insertions, 35 deletions

diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index 119771ff46a..b82050c96f3 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -36,8 +36,11 @@
 #include "i915_drv.h"
 #include "intel_drv.h"
 
-#define PCI_ASLE 0xe4
-#define PCI_ASLS 0xfc
+#define PCI_ASLE		0xe4
+#define PCI_ASLS		0xfc
+#define PCI_SWSCI		0xe8
+#define PCI_SWSCI_SCISEL	(1 << 15)
+#define PCI_SWSCI_GSSCIE	(1 << 0)
 
 #define OPREGION_HEADER_OFFSET 0
 #define OPREGION_ACPI_OFFSET   0x100
@@ -107,25 +110,38 @@ struct opregion_asle {
 	u32 epfm;       /* enabled panel fitting modes */
 	u8 plut[74];    /* panel LUT and identifier */
 	u32 pfmb;       /* PWM freq and min brightness */
-	u8 rsvd[102];
+	u32 cddv;       /* color correction default values */
+	u32 pcft;       /* power conservation features */
+	u32 srot;       /* supported rotation angles */
+	u32 iuer;       /* IUER events */
+	u8 rsvd[86];
 } __attribute__((packed));
 
 /* Driver readiness indicator */
 #define ASLE_ARDY_READY		(1 << 0)
 #define ASLE_ARDY_NOT_READY	(0 << 0)
 
-/* ASLE irq request bits */
-#define ASLE_SET_ALS_ILLUM     (1 << 0)
-#define ASLE_SET_BACKLIGHT     (1 << 1)
-#define ASLE_SET_PFIT          (1 << 2)
-#define ASLE_SET_PWM_FREQ      (1 << 3)
-#define ASLE_REQ_MSK           0xf
-
-/* response bits of ASLE irq request */
-#define ASLE_ALS_ILLUM_FAILED	(1<<10)
-#define ASLE_BACKLIGHT_FAILED	(1<<12)
-#define ASLE_PFIT_FAILED	(1<<14)
-#define ASLE_PWM_FREQ_FAILED	(1<<16)
+/* ASLE Interrupt Command (ASLC) bits */
+#define ASLC_SET_ALS_ILLUM		(1 << 0)
+#define ASLC_SET_BACKLIGHT		(1 << 1)
+#define ASLC_SET_PFIT			(1 << 2)
+#define ASLC_SET_PWM_FREQ		(1 << 3)
+#define ASLC_SUPPORTED_ROTATION_ANGLES	(1 << 4)
+#define ASLC_BUTTON_ARRAY		(1 << 5)
+#define ASLC_CONVERTIBLE_INDICATOR	(1 << 6)
+#define ASLC_DOCKING_INDICATOR		(1 << 7)
+#define ASLC_ISCT_STATE_CHANGE		(1 << 8)
+#define ASLC_REQ_MSK			0x1ff
+/* response bits */
+#define ASLC_ALS_ILLUM_FAILED		(1 << 10)
+#define ASLC_BACKLIGHT_FAILED		(1 << 12)
+#define ASLC_PFIT_FAILED		(1 << 14)
+#define ASLC_PWM_FREQ_FAILED		(1 << 16)
+#define ASLC_ROTATION_ANGLES_FAILED	(1 << 18)
+#define ASLC_BUTTON_ARRAY_FAILED	(1 << 20)
+#define ASLC_CONVERTIBLE_FAILED		(1 << 22)
+#define ASLC_DOCKING_FAILED		(1 << 24)
+#define ASLC_ISCT_STATE_FAILED		(1 << 26)
 
 /* Technology enabled indicator */
 #define ASLE_TCHE_ALS_EN	(1 << 0)
@@ -151,6 +167,60 @@ struct opregion_asle {
 
 #define ASLE_CBLV_VALID         (1<<31)
 
+/* IUER */
+#define ASLE_IUER_DOCKING		(1 << 7)
+#define ASLE_IUER_CONVERTIBLE		(1 << 6)
+#define ASLE_IUER_ROTATION_LOCK_BTN	(1 << 4)
+#define ASLE_IUER_VOLUME_DOWN_BTN	(1 << 3)
+#define ASLE_IUER_VOLUME_UP_BTN		(1 << 2)
+#define ASLE_IUER_WINDOWS_BTN		(1 << 1)
+#define ASLE_IUER_POWER_BTN		(1 << 0)
+
+/* Software System Control Interrupt (SWSCI) */
+#define SWSCI_SCIC_INDICATOR		(1 << 0)
+#define SWSCI_SCIC_MAIN_FUNCTION_SHIFT	1
+#define SWSCI_SCIC_MAIN_FUNCTION_MASK	(0xf << 1)
+#define SWSCI_SCIC_SUB_FUNCTION_SHIFT	8
+#define SWSCI_SCIC_SUB_FUNCTION_MASK	(0xff << 8)
+#define SWSCI_SCIC_EXIT_PARAMETER_SHIFT	8
+#define SWSCI_SCIC_EXIT_PARAMETER_MASK	(0xff << 8)
+#define SWSCI_SCIC_EXIT_STATUS_SHIFT	5
+#define SWSCI_SCIC_EXIT_STATUS_MASK	(7 << 5)
+#define SWSCI_SCIC_EXIT_STATUS_SUCCESS	1
+
+#define SWSCI_FUNCTION_CODE(main, sub) \
+	((main) << SWSCI_SCIC_MAIN_FUNCTION_SHIFT | \
+	 (sub) << SWSCI_SCIC_SUB_FUNCTION_SHIFT)
+
+/* SWSCI: Get BIOS Data (GBDA) */
+#define SWSCI_GBDA			4
+#define SWSCI_GBDA_SUPPORTED_CALLS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 0)
+#define SWSCI_GBDA_REQUESTED_CALLBACKS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 1)
+#define SWSCI_GBDA_BOOT_DISPLAY_PREF	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 4)
+#define SWSCI_GBDA_PANEL_DETAILS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 5)
+#define SWSCI_GBDA_TV_STANDARD		SWSCI_FUNCTION_CODE(SWSCI_GBDA, 6)
+#define SWSCI_GBDA_INTERNAL_GRAPHICS	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 7)
+#define SWSCI_GBDA_SPREAD_SPECTRUM	SWSCI_FUNCTION_CODE(SWSCI_GBDA, 10)
+
+/* SWSCI: System BIOS Callbacks (SBCB) */
+#define SWSCI_SBCB			6
+#define SWSCI_SBCB_SUPPORTED_CALLBACKS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 0)
+#define SWSCI_SBCB_INIT_COMPLETION	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 1)
+#define SWSCI_SBCB_PRE_HIRES_SET_MODE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 3)
+#define SWSCI_SBCB_POST_HIRES_SET_MODE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 4)
+#define SWSCI_SBCB_DISPLAY_SWITCH	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 5)
+#define SWSCI_SBCB_SET_TV_FORMAT	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 6)
+#define SWSCI_SBCB_ADAPTER_POWER_STATE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 7)
+#define SWSCI_SBCB_DISPLAY_POWER_STATE	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 8)
+#define SWSCI_SBCB_SET_BOOT_DISPLAY	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 9)
+#define SWSCI_SBCB_SET_PANEL_DETAILS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 10)
+#define SWSCI_SBCB_SET_INTERNAL_GFX	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 11)
+#define SWSCI_SBCB_POST_HIRES_TO_DOS_FS	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 16)
+#define SWSCI_SBCB_SUSPEND_RESUME	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 17)
+#define SWSCI_SBCB_SET_SPREAD_SPECTRUM	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 18)
+#define SWSCI_SBCB_POST_VBE_PM		SWSCI_FUNCTION_CODE(SWSCI_SBCB, 19)
+#define SWSCI_SBCB_ENABLE_DISABLE_AUDIO	SWSCI_FUNCTION_CODE(SWSCI_SBCB, 21)
+
 #define ACPI_OTHER_OUTPUT (0<<8)
 #define ACPI_VGA_OUTPUT (1<<8)
 #define ACPI_TV_OUTPUT (2<<8)
@@ -158,6 +228,171 @@ struct opregion_asle {
 #define ACPI_LVDS_OUTPUT (4<<8)
 
 #ifdef CONFIG_ACPI
+static int swsci(struct drm_device *dev, u32 function, u32 parm, u32 *parm_out)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct opregion_swsci __iomem *swsci = dev_priv->opregion.swsci;
+	u32 main_function, sub_function, scic;
+	u16 pci_swsci;
+	u32 dslp;
+
+	if (!swsci)
+		return -ENODEV;
+
+	main_function = (function & SWSCI_SCIC_MAIN_FUNCTION_MASK) >>
+		SWSCI_SCIC_MAIN_FUNCTION_SHIFT;
+	sub_function = (function & SWSCI_SCIC_SUB_FUNCTION_MASK) >>
+		SWSCI_SCIC_SUB_FUNCTION_SHIFT;
+
+	/* Check if we can call the function. See swsci_setup for details. */
+	if (main_function == SWSCI_SBCB) {
+		if ((dev_priv->opregion.swsci_sbcb_sub_functions &
+		     (1 << sub_function)) == 0)
+			return -EINVAL;
+	} else if (main_function == SWSCI_GBDA) {
+		if ((dev_priv->opregion.swsci_gbda_sub_functions &
+		     (1 << sub_function)) == 0)
+			return -EINVAL;
+	}
+
+	/* Driver sleep timeout in ms. */
+	dslp = ioread32(&swsci->dslp);
+	if (!dslp) {
+		/* The spec says 2ms should be the default, but it's too small
+		 * for some machines. */
+		dslp = 50;
+	} else if (dslp > 500) {
+		/* Hey bios, trust must be earned. */
+		WARN_ONCE(1, "excessive driver sleep timeout (DSPL) %u\n", dslp);
+		dslp = 500;
+	}
+
+	/* The spec tells us to do this, but we are the only user... */
+	scic = ioread32(&swsci->scic);
+	if (scic & SWSCI_SCIC_INDICATOR) {
+		DRM_DEBUG_DRIVER("SWSCI request already in progress\n");
+		return -EBUSY;
+	}
+
+	scic = function | SWSCI_SCIC_INDICATOR;
+
+	iowrite32(parm, &swsci->parm);
+	iowrite32(scic, &swsci->scic);
+
+	/* Ensure SCI event is selected and event trigger is cleared. */
+	pci_read_config_word(dev->pdev, PCI_SWSCI, &pci_swsci);
+	if (!(pci_swsci & PCI_SWSCI_SCISEL) || (pci_swsci & PCI_SWSCI_GSSCIE)) {
+		pci_swsci |= PCI_SWSCI_SCISEL;
+		pci_swsci &= ~PCI_SWSCI_GSSCIE;
+		pci_write_config_word(dev->pdev, PCI_SWSCI, pci_swsci);
+	}
+
+	/* Use event trigger to tell bios to check the mail. */
+	pci_swsci |= PCI_SWSCI_GSSCIE;
+	pci_write_config_word(dev->pdev, PCI_SWSCI, pci_swsci);
+
+	/* Poll for the result. */
+#define C (((scic = ioread32(&swsci->scic)) & SWSCI_SCIC_INDICATOR) == 0)
+	if (wait_for(C, dslp)) {
+		DRM_DEBUG_DRIVER("SWSCI request timed out\n");
+		return -ETIMEDOUT;
+	}
+
+	scic = (scic & SWSCI_SCIC_EXIT_STATUS_MASK) >>
+		SWSCI_SCIC_EXIT_STATUS_SHIFT;
+
+	/* Note: scic == 0 is an error! */
+	if (scic != SWSCI_SCIC_EXIT_STATUS_SUCCESS) {
+		DRM_DEBUG_DRIVER("SWSCI request error %u\n", scic);
+		return -EIO;
+	}
+
+	if (parm_out)
+		*parm_out = ioread32(&swsci->parm);
+
+	return 0;
+
+#undef C
+}
+
+#define DISPLAY_TYPE_CRT			0
+#define DISPLAY_TYPE_TV				1
+#define DISPLAY_TYPE_EXTERNAL_FLAT_PANEL	2
+#define DISPLAY_TYPE_INTERNAL_FLAT_PANEL	3
+
+int intel_opregion_notify_encoder(struct intel_encoder *intel_encoder,
+				  bool enable)
+{
+	struct drm_device *dev = intel_encoder->base.dev;
+	u32 parm = 0;
+	u32 type = 0;
+	u32 port;
+
+	/* don't care about old stuff for now */
+	if (!HAS_DDI(dev))
+		return 0;
+
+	port = intel_ddi_get_encoder_port(intel_encoder);
+	if (port == PORT_E) {
+		port = 0;
+	} else {
+		parm |= 1 << port;
+		port++;
+	}
+
+	if (!enable)
+		parm |= 4 << 8;
+
+	switch (intel_encoder->type) {
+	case INTEL_OUTPUT_ANALOG:
+		type = DISPLAY_TYPE_CRT;
+		break;
+	case INTEL_OUTPUT_UNKNOWN:
+	case INTEL_OUTPUT_DISPLAYPORT:
+	case INTEL_OUTPUT_HDMI:
+		type = DISPLAY_TYPE_EXTERNAL_FLAT_PANEL;
+		break;
+	case INTEL_OUTPUT_EDP:
+		type = DISPLAY_TYPE_INTERNAL_FLAT_PANEL;
+		break;
+	default:
+		WARN_ONCE(1, "unsupported intel_encoder type %d\n",
+			  intel_encoder->type);
+		return -EINVAL;
+	}
+
+	parm |= type << (16 + port * 3);
+
+	return swsci(dev, SWSCI_SBCB_DISPLAY_POWER_STATE, parm, NULL);
+}
+
+static const struct {
+	pci_power_t pci_power_state;
+	u32 parm;
+} power_state_map[] = {
+	{ PCI_D0,	0x00 },
+	{ PCI_D1,	0x01 },
+	{ PCI_D2,	0x02 },
+	{ PCI_D3hot,	0x04 },
+	{ PCI_D3cold,	0x04 },
+};
+
+int intel_opregion_notify_adapter(struct drm_device *dev, pci_power_t state)
+{
+	int i;
+
+	if (!HAS_DDI(dev))
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(power_state_map); i++) {
+		if (state == power_state_map[i].pci_power_state)
+			return swsci(dev, SWSCI_SBCB_ADAPTER_POWER_STATE,
+				     power_state_map[i].parm, NULL);
+	}
+
+	return -EINVAL;
+}
+
 static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -166,12 +401,13 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
 	if (!(bclp & ASLE_BCLP_VALID))
-		return ASLE_BACKLIGHT_FAILED;
+		return ASLC_BACKLIGHT_FAILED;
 
 	bclp &= ASLE_BCLP_MSK;
 	if (bclp > 255)
-		return ASLE_BACKLIGHT_FAILED;
+		return ASLC_BACKLIGHT_FAILED;
 
+	DRM_DEBUG_KMS("updating opregion backlight %d/255\n", bclp);
 	intel_panel_set_backlight(dev, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
@@ -183,13 +419,13 @@ static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)
 	/* alsi is the current ALS reading in lux. 0 indicates below sensor
 	   range, 0xffff indicates above sensor range. 1-0xfffe are valid */
 	DRM_DEBUG_DRIVER("Illum is not supported\n");
-	return ASLE_ALS_ILLUM_FAILED;
+	return ASLC_ALS_ILLUM_FAILED;
 }
 
 static u32 asle_set_pwm_freq(struct drm_device *dev, u32 pfmb)
 {
 	DRM_DEBUG_DRIVER("PWM freq is not supported\n");
-	return ASLE_PWM_FREQ_FAILED;
+	return ASLC_PWM_FREQ_FAILED;
 }
 
 static u32 asle_set_pfit(struct drm_device *dev, u32 pfit)
@@ -197,39 +433,106 @@ static u32 asle_set_pfit(struct drm_device *dev, u32 pfit)
 	/* Panel fitting is currently controlled by the X code, so this is a
 	   noop until modesetting support works fully */
 	DRM_DEBUG_DRIVER("Pfit is not supported\n");
-	return ASLE_PFIT_FAILED;
+	return ASLC_PFIT_FAILED;
+}
+
+static u32 asle_set_supported_rotation_angles(struct drm_device *dev, u32 srot)
+{
+	DRM_DEBUG_DRIVER("SROT is not supported\n");
+	return ASLC_ROTATION_ANGLES_FAILED;
+}
+
+static u32 asle_set_button_array(struct drm_device *dev, u32 iuer)
+{
+	if (!iuer)
+		DRM_DEBUG_DRIVER("Button array event is not supported (nothing)\n");
+	if (iuer & ASLE_IUER_ROTATION_LOCK_BTN)
+		DRM_DEBUG_DRIVER("Button array event is not supported (rotation lock)\n");
+	if (iuer & ASLE_IUER_VOLUME_DOWN_BTN)
+		DRM_DEBUG_DRIVER("Button array event is not supported (volume down)\n");
+	if (iuer & ASLE_IUER_VOLUME_UP_BTN)
+		DRM_DEBUG_DRIVER("Button array event is not supported (volume up)\n");
+	if (iuer & ASLE_IUER_WINDOWS_BTN)
+		DRM_DEBUG_DRIVER("Button array event is not supported (windows)\n");
+	if (iuer & ASLE_IUER_POWER_BTN)
+		DRM_DEBUG_DRIVER("Button array event is not supported (power)\n");
+
+	return ASLC_BUTTON_ARRAY_FAILED;
+}
+
+static u32 asle_set_convertible(struct drm_device *dev, u32 iuer)
+{
+	if (iuer & ASLE_IUER_CONVERTIBLE)
+		DRM_DEBUG_DRIVER("Convertible is not supported (clamshell)\n");
+	else
+		DRM_DEBUG_DRIVER("Convertible is not supported (slate)\n");
+
+	return ASLC_CONVERTIBLE_FAILED;
+}
+
+static u32 asle_set_docking(struct drm_device *dev, u32 iuer)
+{
+	if (iuer & ASLE_IUER_DOCKING)
+		DRM_DEBUG_DRIVER("Docking is not supported (docked)\n");
+	else
+		DRM_DEBUG_DRIVER("Docking is not supported (undocked)\n");
+
+	return ASLC_DOCKING_FAILED;
+}
+
+static u32 asle_isct_state(struct drm_device *dev)
+{
+	DRM_DEBUG_DRIVER("ISCT is not supported\n");
+	return ASLC_ISCT_STATE_FAILED;
 }
 
 void intel_opregion_asle_intr(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct opregion_asle __iomem *asle = dev_priv->opregion.asle;
-	u32 asle_stat = 0;
-	u32 asle_req;
+	u32 aslc_stat = 0;
+	u32 aslc_req;
 
 	if (!asle)
 		return;
 
-	asle_req = ioread32(&asle->aslc) & ASLE_REQ_MSK;
+	aslc_req = ioread32(&asle->aslc);
 
-	if (!asle_req) {
-		DRM_DEBUG_DRIVER("non asle set request??\n");
+	if (!(aslc_req & ASLC_REQ_MSK)) {
+		DRM_DEBUG_DRIVER("No request on ASLC interrupt 0x%08x\n",
+				 aslc_req);
 		return;
 	}
 
-	if (asle_req & ASLE_SET_ALS_ILLUM)
-		asle_stat |= asle_set_als_illum(dev, ioread32(&asle->alsi));
+	if (aslc_req & ASLC_SET_ALS_ILLUM)
+		aslc_stat |= asle_set_als_illum(dev, ioread32(&asle->alsi));
+
+	if (aslc_req & ASLC_SET_BACKLIGHT)
+		aslc_stat |= asle_set_backlight(dev, ioread32(&asle->bclp));
+
+	if (aslc_req & ASLC_SET_PFIT)
+		aslc_stat |= asle_set_pfit(dev, ioread32(&asle->pfit));
+
+	if (aslc_req & ASLC_SET_PWM_FREQ)
+		aslc_stat |= asle_set_pwm_freq(dev, ioread32(&asle->pfmb));
 
-	if (asle_req & ASLE_SET_BACKLIGHT)
-		asle_stat |= asle_set_backlight(dev, ioread32(&asle->bclp));
+	if (aslc_req & ASLC_SUPPORTED_ROTATION_ANGLES)
+		aslc_stat |= asle_set_supported_rotation_angles(dev,
+							ioread32(&asle->srot));
 
-	if (asle_req & ASLE_SET_PFIT)
-		asle_stat |= asle_set_pfit(dev, ioread32(&asle->pfit));
+	if (aslc_req & ASLC_BUTTON_ARRAY)
+		aslc_stat |= asle_set_button_array(dev, ioread32(&asle->iuer));
 
-	if (asle_req & ASLE_SET_PWM_FREQ)
-		asle_stat |= asle_set_pwm_freq(dev, ioread32(&asle->pfmb));
+	if (aslc_req & ASLC_CONVERTIBLE_INDICATOR)
+		aslc_stat |= asle_set_convertible(dev, ioread32(&asle->iuer));
 
-	iowrite32(asle_stat, &asle->aslc);
+	if (aslc_req & ASLC_DOCKING_INDICATOR)
+		aslc_stat |= asle_set_docking(dev, ioread32(&asle->iuer));
+
+	if (aslc_req & ASLC_ISCT_STATE_CHANGE)
+		aslc_stat |= asle_isct_state(dev);
+
+	iowrite32(aslc_stat, &asle->aslc);
 }
 
 #define ACPI_EV_DISPLAY_SWITCH (1<<0)
@@ -446,8 +749,68 @@ void intel_opregion_fini(struct drm_device *dev)
 	opregion->swsci = NULL;
 	opregion->asle = NULL;
 	opregion->vbt = NULL;
+	opregion->lid_state = NULL;
+}
+
+static void swsci_setup(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_opregion *opregion = &dev_priv->opregion;
+	bool requested_callbacks = false;
+	u32 tmp;
+
+	/* Sub-function code 0 is okay, let's allow them. */
+	opregion->swsci_gbda_sub_functions = 1;
+	opregion->swsci_sbcb_sub_functions = 1;
+
+	/* We use GBDA to ask for supported GBDA calls. */
+	if (swsci(dev, SWSCI_GBDA_SUPPORTED_CALLS, 0, &tmp) == 0) {
+		/* make the bits match the sub-function codes */
+		tmp <<= 1;
+		opregion->swsci_gbda_sub_functions |= tmp;
+	}
+
+	/*
+	 * We also use GBDA to ask for _requested_ SBCB callbacks. The driver
+	 * must not call interfaces that are not specifically requested by the
+	 * bios.
+	 */
+	if (swsci(dev, SWSCI_GBDA_REQUESTED_CALLBACKS, 0, &tmp) == 0) {
+		/* here, the bits already match sub-function codes */
+		opregion->swsci_sbcb_sub_functions |= tmp;
+		requested_callbacks = true;
+	}
+
+	/*
+	 * But we use SBCB to ask for _supported_ SBCB calls. This does not mean
+	 * the callback is _requested_. But we still can't call interfaces that
+	 * are not requested.
+	 */
+	if (swsci(dev, SWSCI_SBCB_SUPPORTED_CALLBACKS, 0, &tmp) == 0) {
+		/* make the bits match the sub-function codes */
+		u32 low = tmp & 0x7ff;
+		u32 high = tmp & ~0xfff; /* bit 11 is reserved */
+		tmp = (high << 4) | (low << 1) | 1;
+
+		/* best guess what to do with supported wrt requested */
+		if (requested_callbacks) {
+			u32 req = opregion->swsci_sbcb_sub_functions;
+			if ((req & tmp) != req)
+				DRM_DEBUG_DRIVER("SWSCI BIOS requested (%08x) SBCB callbacks that are not supported (%08x)\n", req, tmp);
+			/* XXX: for now, trust the requested callbacks */
+			/* opregion->swsci_sbcb_sub_functions &= tmp; */
+		} else {
+			opregion->swsci_sbcb_sub_functions |= tmp;
+		}
+	}
+
+	DRM_DEBUG_DRIVER("SWSCI GBDA callbacks %08x, SBCB callbacks %08x\n",
+			 opregion->swsci_gbda_sub_functions,
+			 opregion->swsci_sbcb_sub_functions);
 }
-#endif
+#else /* CONFIG_ACPI */
+static inline void swsci_setup(struct drm_device *dev) {}
+#endif  /* CONFIG_ACPI */
 
 int intel_opregion_setup(struct drm_device *dev)
 {
@@ -490,6 +853,7 @@ int intel_opregion_setup(struct drm_device *dev)
 	if (mboxes & MBOX_SWSCI) {
 		DRM_DEBUG_DRIVER("SWSCI supported\n");
 		opregion->swsci = base + OPREGION_SWSCI_OFFSET;
+		swsci_setup(dev);
 	}
 	if (mboxes & MBOX_ASLE) {
 		DRM_DEBUG_DRIVER("ASLE supported\n");