This is a modified version of Hong's patch from last month, with a few

modifications to make it work correctly on my test hardware (altered the
backlight write function, made it enable the legacy backlight controller
interrupts on mobile hardware, sorted the interrupt function so we don't
get an excessive number of vblank interrupts). This lets the backlight
keys on my T61 work properly, though there's a 750msec or so delay
between the request and the brightness actually changing - this sounds
awfully like the hardware spinning waiting for a status flag to become
ready, but as far as I can tell they're all set correctly. If anyone can
figure out what's wrong here, it'd be nice to know.

Some of the functions are still stubs and just tell the hardware that
the request was successful. These can be filled in as kernel modesetting
gets integrated. I think it's worth getting this in anyway, since it's
required for backlight control to work properly on some new platforms.

Signed-off-by: Matthew Garrett <mjg@redhat.com>

6 files changed, 449 insertions, 1 deletions

diff --git a/linux-core/Makefile.kernel b/linux-core/Makefile.kernel
index b9f078dd..45a6b1f9 100644
--- a/linux-core/Makefile.kernel
+++ b/linux-core/Makefile.kernel
@@ -20,7 +20,8 @@ r128-objs   := r128_drv.o r128_cce.o r128_state.o r128_irq.o
 mga-objs    := mga_drv.o mga_dma.o mga_state.o mga_warp.o mga_irq.o
 i810-objs   := i810_drv.o i810_dma.o
 i915-objs   := i915_drv.o i915_dma.o i915_irq.o i915_mem.o i915_fence.o \
-		i915_buffer.o i915_compat.o i915_execbuf.o i915_suspend.o
+		i915_buffer.o i915_compat.o i915_execbuf.o i915_suspend.o \
+		i915_opregion.o
 nouveau-objs := nouveau_drv.o nouveau_state.o nouveau_fifo.o nouveau_mem.o \
 		nouveau_object.o nouveau_irq.o nouveau_notifier.o nouveau_swmthd.o \
 		nouveau_sgdma.o nouveau_dma.o nouveau_bo.o nouveau_fence.o \
diff --git a/linux-core/i915_drv.c b/linux-core/i915_drv.c
index be25239d..abb45de7 100644
--- a/linux-core/i915_drv.c
+++ b/linux-core/i915_drv.c
@@ -80,6 +80,8 @@ static int i915_suspend(struct drm_device *dev, pm_message_t state)
 
 	i915_save_state(dev);
 
+	intel_opregion_free(dev);
+
 	if (state.event == PM_EVENT_SUSPEND) {
 		/* Shut down the device */
 		pci_disable_device(dev->pdev);
@@ -99,6 +101,8 @@ static int i915_resume(struct drm_device *dev)
 
 	i915_restore_state(dev);
 
+	intel_opregion_init(dev);
+
 	return 0;
 }
 
diff --git a/linux-core/i915_opregion.c b/linux-core/i915_opregion.c
new file mode 100644
index 00000000..e691571a
--- /dev/null
+++ b/linux-core/i915_opregion.c
@@ -0,0 +1,386 @@
+/*
+ *
+ * Copyright 2008 Intel Corporation <hong.liu@intel.com>
+ * Copyright 2008 Red Hat <mjg@redhat.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NON-INFRINGEMENT.  IN NO EVENT SHALL INTEL AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include <linux/acpi.h>
+
+#include "drmP.h"
+#include "i915_drm.h"
+#include "i915_drv.h"
+
+#define PCI_ASLE 0xe4
+#define PCI_ASLS 0xfc
+
+#define OPREGION_SZ            (8*1024)
+#define OPREGION_HEADER_OFFSET 0
+#define OPREGION_ACPI_OFFSET   0x100
+#define OPREGION_SWSCI_OFFSET  0x200
+#define OPREGION_ASLE_OFFSET   0x300
+#define OPREGION_VBT_OFFSET    0x1000
+
+#define OPREGION_SIGNATURE "IntelGraphicsMem"
+#define MBOX_ACPI      (1<<0)
+#define MBOX_SWSCI     (1<<1)
+#define MBOX_ASLE      (1<<2)
+
+/* _DOD id definitions */
+#define OUTPUT_CONNECTOR_MSK   0xf000
+#define OUTPUT_CONNECTOR_OFFSET        12
+
+#define OUTPUT_PORT_MSK                0x00f0
+#define OUTPUT_PORT_OFFSET     4
+  #define OUTPUT_PORT_ANALOG   0
+  #define OUTPUT_PORT_LVDS     1
+  #define OUTPUT_PORT_SDVOB    2
+  #define OUTPUT_PORT_SDVOC    3
+  #define OUTPUT_PORT_TV       4
+
+#define OUTPUT_DISPLAY_MSK     0x0f00
+#define OUTPUT_DISPLAY_OFFSET  8
+  #define OUTPUT_DISPLAY_OTHER         0
+  #define OUTPUT_DISPLAY_VGA           1
+  #define OUTPUT_DISPLAY_TV            2
+  #define OUTPUT_DISPLAY_DIGI          3
+  #define OUTPUT_DISPLAY_FLAT_PANEL    4
+
+/* predefined id for integrated LVDS and VGA connector */
+#define OUTPUT_INT_LVDS        0x00000110
+#define OUTPUT_INT_VGA 0x80000100
+
+struct opregion_header {
+       u8 signature[16];
+       u32 size;
+       u32 opregion_ver;
+       u8 bios_ver[32];
+       u8 vbios_ver[16];
+       u8 driver_ver[16];
+       u32 mboxes;
+       u8 reserved[164];
+} __attribute__((packed));
+
+/* OpRegion mailbox #1: public ACPI methods */
+struct opregion_acpi {
+       u32 drdy;       /* driver readiness */
+       u32 csts;       /* notification status */
+       u32 cevt;       /* current event */
+       u8 rsvd1[20];
+       u32 didl[8];    /* supported display devices ID list */
+       u32 cpdl[8];    /* currently presented display list */
+       u32 cadl[8];    /* currently active display list */
+       u32 nadl[8];    /* next active devices list */
+       u32 aslp;       /* ASL sleep time-out */
+       u32 tidx;       /* toggle table index */
+       u32 chpd;       /* current hotplug enable indicator */
+       u32 clid;       /* current lid state*/
+       u32 cdck;       /* current docking state */
+       u32 sxsw;       /* Sx state resume */
+       u32 evts;       /* ASL supported events */
+       u32 cnot;       /* current OS notification */
+       u32 nrdy;       /* driver status */
+       u8 rsvd2[60];
+} __attribute__((packed));
+
+/* OpRegion mailbox #2: SWSCI */
+struct opregion_swsci {
+       u32 scic;       /* SWSCI command|status|data */
+       u32 parm;       /* command parameters */
+       u32 dslp;       /* driver sleep time-out */
+       u8 rsvd[244];
+} __attribute__((packed));
+
+/* OpRegion mailbox #3: ASLE */
+struct opregion_asle {
+       u32 ardy;       /* driver readiness */
+       u32 aslc;       /* ASLE interrupt command */
+       u32 tche;       /* technology enabled indicator */
+       u32 alsi;       /* current ALS illuminance reading */
+       u32 bclp;       /* backlight brightness to set */
+       u32 pfit;       /* panel fitting state */
+       u32 cblv;       /* current brightness level */
+       u16 bclm[20];   /* backlight level duty cycle mapping table */
+       u32 cpfm;       /* current panel fitting mode */
+       u32 epfm;       /* enabled panel fitting modes */
+       u8 plut[74];    /* panel LUT and identifier */
+       u32 pfmb;       /* PWM freq and min brightness */
+       u8 rsvd[102];
+} __attribute__((packed));
+
+/* 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_FAIL    (2<<10)
+#define ASLE_BACKLIGHT_FAIL    (2<<12)
+#define ASLE_PFIT_FAIL         (2<<14)
+#define ASLE_PWM_FREQ_FAIL     (2<<16)
+
+/* ASLE backlight brightness to set */
+#define ASLE_BCLP_VALID                (1<<31)
+#define ASLE_BCLP_MSK          (~(1<<31))
+
+/* ASLE panel fitting request */
+#define ASLE_PFIT_VALID         (1<<31)
+#define ASLE_PFIT_CENTER (1<<0)
+#define ASLE_PFIT_STRETCH_TEXT (1<<1)
+#define ASLE_PFIT_STRETCH_GFX (1<<2)
+
+/* PWM frequency and minimum brightness */
+#define ASLE_PFMB_BRIGHTNESS_MASK (0xff)
+#define ASLE_PFMB_BRIGHTNESS_VALID (1<<8)
+#define ASLE_PFMB_PWM_MASK (0x7ffffe00)
+#define ASLE_PFMB_PWM_VALID (1<<31)
+
+#define ASLE_CBLV_VALID         (1<<31)
+
+static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct opregion_asle *asle = dev_priv->opregion.asle;
+	u32 blc_pwm_ctl;
+	
+	if (!(bclp & ASLE_BCLP_VALID))
+		return ASLE_BACKLIGHT_FAIL;
+	
+	bclp &= ASLE_BCLP_MSK;
+	if (bclp < 0 || bclp > 255)
+		return ASLE_BACKLIGHT_FAIL;
+	
+	blc_pwm_ctl = I915_READ(BLC_PWM_CTL);
+	blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK;
+	I915_WRITE(BLC_PWM_CTL, blc_pwm_ctl | ((bclp * 0x101) -1));
+	asle->cblv = (bclp*0x64)/0xff | ASLE_CBLV_VALID;
+	
+	return 0;
+}
+
+static u32 asle_set_als_illum(struct drm_device *dev, u32 alsi)
+{
+	return 0;
+}
+
+static u32 asle_set_pwm_freq(struct drm_device *dev, u32 pfmb)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	if (pfmb & ASLE_PFMB_PWM_VALID) {
+		u32 blc_pwm_ctl = I915_READ(BLC_PWM_CTL);
+		u32 pwm = pfmb & ASLE_PFMB_PWM_MASK;
+		blc_pwm_ctl &= BACKLIGHT_DUTY_CYCLE_MASK;
+		pwm = pwm >> 9;
+		// FIXME - what do we do with the PWM?
+	}
+	return 0;
+}
+
+static u32 asle_set_pfit(struct drm_device *dev, u32 pfit)
+{
+	if (!(pfit & ASLE_PFIT_VALID))
+		return ASLE_PFIT_FAIL;
+	return 0;
+}
+
+void opregion_asle_intr(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct opregion_asle *asle = dev_priv->opregion.asle;
+	u32 asle_stat = 0;
+	u32 asle_req;
+
+	if (!asle)
+		return;
+
+	asle_req = asle->aslc & ASLE_REQ_MSK;
+	
+	if (!asle_req) {
+		DRM_DEBUG("non asle set request??\n");
+		return;
+	}
+
+	if (asle_req & ASLE_SET_ALS_ILLUM)
+		asle_stat |= asle_set_als_illum(dev, asle->alsi);
+	
+	if (asle_req & ASLE_SET_BACKLIGHT)
+		asle_stat |= asle_set_backlight(dev, asle->bclp);
+	
+	if (asle_req & ASLE_SET_PFIT)
+		asle_stat |= asle_set_pfit(dev, asle->pfit);
+	
+	if (asle_req & ASLE_SET_PWM_FREQ)
+		asle_stat |= asle_set_pwm_freq(dev, asle->pfmb);
+	
+	asle->aslc = asle_stat;
+}
+
+#define ASLE_ALS_EN    (1<<0)
+#define ASLE_BLC_EN    (1<<1)
+#define ASLE_PFIT_EN   (1<<2)
+#define ASLE_PFMB_EN   (1<<3)
+
+void opregion_enable_asle(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct opregion_asle *asle = dev_priv->opregion.asle;
+
+	if (asle) {
+		u32 pipeb_stats = I915_READ(PIPEBSTAT);
+		if (IS_MOBILE(dev)) {
+			/* Some hardware uses the legacy backlight controller
+			   to signal interrupts, so we need to set up pipe B
+			   to generate an IRQ on writes */
+			I915_WRITE(PIPEBSTAT, pipeb_stats |= 
+				   I915_LEGACY_BLC_EVENT_ENABLE);
+			dev_priv->irq_enable_reg |= 
+				(I915_ASLE_INTERRUPT 
+				 | I915_DISPLAY_PIPE_B_EVENT_INTERRUPT);
+		} else
+			dev_priv->irq_enable_reg |= I915_ASLE_INTERRUPT;
+		
+		asle->tche = ASLE_ALS_EN | ASLE_BLC_EN | ASLE_PFIT_EN | 
+			ASLE_PFMB_EN;
+		asle->ardy = 1;
+	}
+}
+
+#define ACPI_EV_DISPLAY_SWITCH (1<<0)
+#define ACPI_EV_LID            (1<<1)
+#define ACPI_EV_DOCK           (1<<2)
+
+static struct intel_opregion *system_opregion;
+
+int intel_opregion_video_event(struct notifier_block *nb, unsigned long val,
+                               void *data)
+{
+	/* The only video events relevant to opregion are 0x80. These indicate
+	   either a docking event, lid switch or display switch request. In
+	   Linux, these are handled by the dock, button and video drivers.
+	   We might want to fix the video driver to be opregion-aware in
+	   future, but right now we just indicate to the firmware that the
+	   request has been handled */
+	
+	struct opregion_acpi *acpi;
+
+	if (!system_opregion)
+		return NOTIFY_DONE;
+	
+	acpi = system_opregion->acpi;
+	acpi->csts = 0;
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block intel_opregion_notifier = {
+	.notifier_call = intel_opregion_video_event,
+};
+
+int intel_opregion_init(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_opregion *opregion = &dev_priv->opregion;
+	void *base;
+	u32 asls, mboxes;
+	int err = 0;
+	
+	pci_read_config_dword(dev->pdev, PCI_ASLS, &asls);
+	DRM_DEBUG("graphic opregion physical addr: 0x%x\n", asls);
+	if (asls == 0) {
+		DRM_DEBUG("ACPI OpRegion not supported!\n");
+		return -ENOTSUPP;
+	}
+	
+	base = ioremap(asls, OPREGION_SZ);
+	if (!base)
+		return -ENOMEM;
+	
+	opregion->header = base;
+	if (memcmp(opregion->header->signature, OPREGION_SIGNATURE, 16)) {
+		DRM_DEBUG("opregion signature mismatch\n");
+		err = -EINVAL;
+		goto err_out;
+	}
+	
+	mboxes = opregion->header->mboxes;
+	if (mboxes & MBOX_ACPI) {
+		DRM_DEBUG("Public ACPI methods supported\n");
+		opregion->acpi = base + OPREGION_ACPI_OFFSET;
+	} else {
+		DRM_DEBUG("Public ACPI methods not supported\n");
+		err = -ENOTSUPP;
+		goto err_out;
+	}
+	opregion->enabled = 1;
+	
+	if (mboxes & MBOX_SWSCI) {
+		DRM_DEBUG("SWSCI supported\n");
+		opregion->swsci = base + OPREGION_SWSCI_OFFSET;
+	}
+	if (mboxes & MBOX_ASLE) {
+		DRM_DEBUG("ASLE supported\n");
+		opregion->asle = base + OPREGION_ASLE_OFFSET;
+	}
+	
+	/* Notify BIOS we are ready to handle ACPI video ext notifs.
+	 * Right now, all the events are handled by the ACPI video module.
+	 * We don't actually need to do anything with them. */
+	opregion->acpi->csts = 0;
+	opregion->acpi->drdy = 1;
+
+	system_opregion = opregion;
+	register_acpi_notifier(&intel_opregion_notifier);
+	
+	return 0;
+	
+err_out:
+	iounmap(opregion->header);
+	opregion->header = NULL;
+	return err;
+}
+
+void intel_opregion_free(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_opregion *opregion = &dev_priv->opregion;
+	
+	if (!opregion->enabled)
+		return;
+	
+	opregion->acpi->drdy = 0;
+	
+	system_opregion = NULL;
+	unregister_acpi_notifier(&intel_opregion_notifier);
+	
+	/* just clear all opregion memory pointers now */
+	iounmap(opregion->header);
+	opregion->header = NULL;
+	opregion->acpi = NULL;
+	opregion->swsci = NULL;
+	opregion->asle = NULL;
+	
+	opregion->enabled = 0;
+}
diff --git a/shared-core/i915_dma.c b/shared-core/i915_dma.c
index 27d152cb..ad6e1293 100644
--- a/shared-core/i915_dma.c
+++ b/shared-core/i915_dma.c
@@ -1038,6 +1038,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
 	intel_init_chipset_flush_compat(dev);
 #endif
+	intel_opregion_init(dev);
 #endif
 
 	return ret;
@@ -1050,6 +1051,10 @@ int i915_driver_unload(struct drm_device *dev)
 	if (dev_priv->mmio_map)
 		drm_rmmap(dev, dev_priv->mmio_map);
 
+#ifdef __linux__
+	intel_opregion_free(dev);
+#endif
+
 	drm_free(dev->dev_private, sizeof(drm_i915_private_t),
 		 DRM_MEM_DRIVER);
 #ifdef __linux__
diff --git a/shared-core/i915_drv.h b/shared-core/i915_drv.h
index fa3305ba..421572cd 100644
--- a/shared-core/i915_drv.h
+++ b/shared-core/i915_drv.h
@@ -105,6 +105,22 @@ typedef struct _drm_i915_vbl_swap {
 	int flip;
 } drm_i915_vbl_swap_t;
 
+#ifdef __linux__
+struct opregion_header;
+struct opregion_acpi;
+struct opregion_swsci;
+struct opregion_asle;
+
+struct intel_opregion {
+	struct opregion_header *header;
+	struct opregion_acpi *acpi;
+	struct opregion_swsci *swsci;
+	struct opregion_asle *asle;
+
+	int enabled;
+};
+#endif
+
 typedef struct drm_i915_private {
 	drm_local_map_t *sarea;
 	drm_local_map_t *mmio_map;
@@ -158,6 +174,11 @@ typedef struct drm_i915_private {
 	struct drm_buffer_object *sarea_bo;
 	struct drm_bo_kmap_obj sarea_kmap;
 #endif
+
+#ifdef __linux__
+	struct intel_opregion opregion;
+#endif
+
 	/* Register state */
 	u8 saveLBB;
 	u32 saveDSPACNTR;
@@ -343,6 +364,14 @@ int i915_execbuffer(struct drm_device *dev, void *data,
 #endif
 
 #ifdef __linux__
+/* i915_opregion.c */
+extern int intel_opregion_init(struct drm_device *dev);
+extern void intel_opregion_free(struct drm_device *dev);
+extern void opregion_asle_intr(struct drm_device *dev);
+extern void opregion_enable_asle(struct drm_device *dev);
+#endif
+
+#ifdef __linux__
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
 extern void intel_init_chipset_flush_compat(struct drm_device *dev);
 extern void intel_fini_chipset_flush_compat(struct drm_device *dev);
@@ -613,6 +642,7 @@ extern int i915_wait_ring(struct drm_device * dev, int n, const char *caller);
 #define   I915_DISPLAY_PIPE_B_EVENT_INTERRUPT		(1<<4)
 #define   I915_DEBUG_INTERRUPT				(1<<2)
 #define   I915_USER_INTERRUPT				(1<<1)
+#define   I915_ASLE_INTERRUPT				(1<<0)
 #define EIR		0x020b0
 #define EMR		0x020b4
 #define ESR		0x020b8
diff --git a/shared-core/i915_irq.c b/shared-core/i915_irq.c
index 28f9f6af..d7fa47d3 100644
--- a/shared-core/i915_irq.c
+++ b/shared-core/i915_irq.c
@@ -474,15 +474,33 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 	}
 	if (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) {
 		pipeb_stats = I915_READ(PIPEBSTAT);
+		/* Ack the event */
+		I915_WRITE(PIPEBSTAT, pipeb_stats);
+
+		/* The vblank interrupt gets enabled even if we didn't ask for
+		   it, so make sure it's shut down again */
+		if (!(dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B))
+			pipeb_stats &= ~(I915_VBLANK_INTERRUPT_ENABLE);
+
 		if (pipeb_stats & (PIPE_START_VBLANK_INTERRUPT_STATUS|
 				   PIPE_VBLANK_INTERRUPT_STATUS))
 		{
 			vblank++;
 			drm_handle_vblank(dev, i915_get_plane(dev, 1));
 		}
+
+#ifdef __linux__
+		if (pipeb_stats & I915_LEGACY_BLC_EVENT_ENABLE)
+			opregion_asle_intr(dev);
+#endif
 		I915_WRITE(PIPEBSTAT, pipeb_stats);
 	}
 
+#ifdef __linux__
+	if (iir & I915_ASLE_INTERRUPT)
+		opregion_asle_intr(dev);
+#endif
+
 	if (dev_priv->sarea_priv)
 	    dev_priv->sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
 
@@ -703,6 +721,10 @@ static void i915_enable_interrupt (struct drm_device *dev)
 	
 	dev_priv->irq_enable_reg |= I915_USER_INTERRUPT;
 
+#ifdef __linux__
+	opregion_enable_asle(dev);
+#endif
+
 	I915_WRITE(IER, dev_priv->irq_enable_reg);
 	dev_priv->irq_enabled = 1;
 }