kolibrios-gitea/drivers/video/drm/i915/intel_uncore.c
Sergey Semyonov (Serge) 4b0faaf65f i915: flush cached memory
git-svn-id: svn://kolibrios.org@4293 a494cfbc-eb01-0410-851d-a64ba20cac60
2013-11-26 06:18:53 +00:00

603 lines
18 KiB
C

/*
* Copyright © 2013 Intel Corporation
*
* 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, sublicense,
* 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 NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS 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 "i915_drv.h"
#include "intel_drv.h"
#define FORCEWAKE_ACK_TIMEOUT_MS 2
#define __raw_i915_read8(dev_priv__, reg__) readb((dev_priv__)->regs + (reg__))
#define __raw_i915_write8(dev_priv__, reg__, val__) writeb(val__, (dev_priv__)->regs + (reg__))
#define __raw_i915_read16(dev_priv__, reg__) readw((dev_priv__)->regs + (reg__))
#define __raw_i915_write16(dev_priv__, reg__, val__) writew(val__, (dev_priv__)->regs + (reg__))
#define __raw_i915_read32(dev_priv__, reg__) readl((dev_priv__)->regs + (reg__))
#define __raw_i915_write32(dev_priv__, reg__, val__) writel(val__, (dev_priv__)->regs + (reg__))
#define __raw_i915_read64(dev_priv__, reg__) readq((dev_priv__)->regs + (reg__))
#define __raw_i915_write64(dev_priv__, reg__, val__) writeq(val__, (dev_priv__)->regs + (reg__))
#define __raw_posting_read(dev_priv__, reg__) (void)__raw_i915_read32(dev_priv__, reg__)
static void __gen6_gt_wait_for_thread_c0(struct drm_i915_private *dev_priv)
{
u32 gt_thread_status_mask;
if (IS_HASWELL(dev_priv->dev))
gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK_HSW;
else
gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK;
/* w/a for a sporadic read returning 0 by waiting for the GT
* thread to wake up.
*/
if (wait_for_atomic_us((__raw_i915_read32(dev_priv, GEN6_GT_THREAD_STATUS_REG) & gt_thread_status_mask) == 0, 500))
DRM_ERROR("GT thread status wait timed out\n");
}
static void __gen6_gt_force_wake_reset(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE, 0);
/* something from same cacheline, but !FORCEWAKE */
__raw_posting_read(dev_priv, ECOBUS);
}
static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK) & 1) == 0,
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
__raw_i915_write32(dev_priv, FORCEWAKE, 1);
/* something from same cacheline, but !FORCEWAKE */
__raw_posting_read(dev_priv, ECOBUS);
if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK) & 1),
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for forcewake to ack request.\n");
/* WaRsForcewakeWaitTC0:snb */
__gen6_gt_wait_for_thread_c0(dev_priv);
}
static void __gen6_gt_force_wake_mt_reset(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE_MT, _MASKED_BIT_DISABLE(0xffff));
/* something from same cacheline, but !FORCEWAKE_MT */
__raw_posting_read(dev_priv, ECOBUS);
}
static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
{
u32 forcewake_ack;
if (IS_HASWELL(dev_priv->dev))
forcewake_ack = FORCEWAKE_ACK_HSW;
else
forcewake_ack = FORCEWAKE_MT_ACK;
if (wait_for_atomic((__raw_i915_read32(dev_priv, forcewake_ack) & FORCEWAKE_KERNEL) == 0,
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
__raw_i915_write32(dev_priv, FORCEWAKE_MT,
_MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
/* something from same cacheline, but !FORCEWAKE_MT */
__raw_posting_read(dev_priv, ECOBUS);
if (wait_for_atomic((__raw_i915_read32(dev_priv, forcewake_ack) & FORCEWAKE_KERNEL),
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for forcewake to ack request.\n");
/* WaRsForcewakeWaitTC0:ivb,hsw */
__gen6_gt_wait_for_thread_c0(dev_priv);
}
static void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)
{
u32 gtfifodbg;
gtfifodbg = __raw_i915_read32(dev_priv, GTFIFODBG);
if (WARN(gtfifodbg & GT_FIFO_CPU_ERROR_MASK,
"MMIO read or write has been dropped %x\n", gtfifodbg))
__raw_i915_write32(dev_priv, GTFIFODBG, GT_FIFO_CPU_ERROR_MASK);
}
static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE, 0);
/* something from same cacheline, but !FORCEWAKE */
__raw_posting_read(dev_priv, ECOBUS);
gen6_gt_check_fifodbg(dev_priv);
}
static void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE_MT,
_MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
/* something from same cacheline, but !FORCEWAKE_MT */
__raw_posting_read(dev_priv, ECOBUS);
gen6_gt_check_fifodbg(dev_priv);
}
static int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
{
int ret = 0;
if (dev_priv->uncore.fifo_count < GT_FIFO_NUM_RESERVED_ENTRIES) {
int loop = 500;
u32 fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
while (fifo <= GT_FIFO_NUM_RESERVED_ENTRIES && loop--) {
udelay(10);
fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
}
if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES))
++ret;
dev_priv->uncore.fifo_count = fifo;
}
dev_priv->uncore.fifo_count--;
return ret;
}
static void vlv_force_wake_reset(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE_VLV,
_MASKED_BIT_DISABLE(0xffff));
/* something from same cacheline, but !FORCEWAKE_VLV */
__raw_posting_read(dev_priv, FORCEWAKE_ACK_VLV);
}
static void vlv_force_wake_get(struct drm_i915_private *dev_priv)
{
if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_VLV) & FORCEWAKE_KERNEL) == 0,
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
__raw_i915_write32(dev_priv, FORCEWAKE_VLV,
_MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
__raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV,
_MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_VLV) & FORCEWAKE_KERNEL),
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for GT to ack forcewake request.\n");
if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_MEDIA_VLV) &
FORCEWAKE_KERNEL),
FORCEWAKE_ACK_TIMEOUT_MS))
DRM_ERROR("Timed out waiting for media to ack forcewake request.\n");
/* WaRsForcewakeWaitTC0:vlv */
__gen6_gt_wait_for_thread_c0(dev_priv);
}
static void vlv_force_wake_put(struct drm_i915_private *dev_priv)
{
__raw_i915_write32(dev_priv, FORCEWAKE_VLV,
_MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
__raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV,
_MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
/* The below doubles as a POSTING_READ */
gen6_gt_check_fifodbg(dev_priv);
}
void intel_uncore_early_sanitize(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (HAS_FPGA_DBG_UNCLAIMED(dev))
__raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
}
void intel_uncore_init(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (IS_VALLEYVIEW(dev)) {
dev_priv->uncore.funcs.force_wake_get = vlv_force_wake_get;
dev_priv->uncore.funcs.force_wake_put = vlv_force_wake_put;
} else if (IS_HASWELL(dev)) {
dev_priv->uncore.funcs.force_wake_get = __gen6_gt_force_wake_mt_get;
dev_priv->uncore.funcs.force_wake_put = __gen6_gt_force_wake_mt_put;
} else if (IS_IVYBRIDGE(dev)) {
u32 ecobus;
/* IVB configs may use multi-threaded forcewake */
/* A small trick here - if the bios hasn't configured
* MT forcewake, and if the device is in RC6, then
* force_wake_mt_get will not wake the device and the
* ECOBUS read will return zero. Which will be
* (correctly) interpreted by the test below as MT
* forcewake being disabled.
*/
mutex_lock(&dev->struct_mutex);
__gen6_gt_force_wake_mt_get(dev_priv);
ecobus = __raw_i915_read32(dev_priv, ECOBUS);
__gen6_gt_force_wake_mt_put(dev_priv);
mutex_unlock(&dev->struct_mutex);
if (ecobus & FORCEWAKE_MT_ENABLE) {
dev_priv->uncore.funcs.force_wake_get =
__gen6_gt_force_wake_mt_get;
dev_priv->uncore.funcs.force_wake_put =
__gen6_gt_force_wake_mt_put;
} else {
DRM_INFO("No MT forcewake available on Ivybridge, this can result in issues\n");
DRM_INFO("when using vblank-synced partial screen updates.\n");
dev_priv->uncore.funcs.force_wake_get =
__gen6_gt_force_wake_get;
dev_priv->uncore.funcs.force_wake_put =
__gen6_gt_force_wake_put;
}
} else if (IS_GEN6(dev)) {
dev_priv->uncore.funcs.force_wake_get =
__gen6_gt_force_wake_get;
dev_priv->uncore.funcs.force_wake_put =
__gen6_gt_force_wake_put;
}
}
static void intel_uncore_forcewake_reset(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (IS_VALLEYVIEW(dev)) {
vlv_force_wake_reset(dev_priv);
} else if (INTEL_INFO(dev)->gen >= 6) {
__gen6_gt_force_wake_reset(dev_priv);
if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev))
__gen6_gt_force_wake_mt_reset(dev_priv);
}
}
void intel_uncore_sanitize(struct drm_device *dev)
{
intel_uncore_forcewake_reset(dev);
/* BIOS often leaves RC6 enabled, but disable it for hw init */
intel_disable_gt_powersave(dev);
}
/*
* Generally this is called implicitly by the register read function. However,
* if some sequence requires the GT to not power down then this function should
* be called at the beginning of the sequence followed by a call to
* gen6_gt_force_wake_put() at the end of the sequence.
*/
void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
unsigned long irqflags;
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
if (dev_priv->uncore.forcewake_count++ == 0)
dev_priv->uncore.funcs.force_wake_get(dev_priv);
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
}
/*
* see gen6_gt_force_wake_get()
*/
void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
unsigned long irqflags;
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
if (--dev_priv->uncore.forcewake_count == 0)
dev_priv->uncore.funcs.force_wake_put(dev_priv);
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
}
/* We give fast paths for the really cool registers */
#define NEEDS_FORCE_WAKE(dev_priv, reg) \
((HAS_FORCE_WAKE((dev_priv)->dev)) && \
((reg) < 0x40000) && \
((reg) != FORCEWAKE))
static void
ilk_dummy_write(struct drm_i915_private *dev_priv)
{
/* WaIssueDummyWriteToWakeupFromRC6:ilk Issue a dummy write to wake up
* the chip from rc6 before touching it for real. MI_MODE is masked,
* hence harmless to write 0 into. */
__raw_i915_write32(dev_priv, MI_MODE, 0);
}
static void
hsw_unclaimed_reg_clear(struct drm_i915_private *dev_priv, u32 reg)
{
if (HAS_FPGA_DBG_UNCLAIMED(dev_priv->dev) &&
(__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
DRM_ERROR("Unknown unclaimed register before writing to %x\n",
reg);
__raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
}
}
static void
hsw_unclaimed_reg_check(struct drm_i915_private *dev_priv, u32 reg)
{
if (HAS_FPGA_DBG_UNCLAIMED(dev_priv->dev) &&
(__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
DRM_ERROR("Unclaimed write to %x\n", reg);
__raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
}
}
#define __i915_read(x) \
u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg, bool trace) { \
unsigned long irqflags; \
u##x val = 0; \
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); \
if (dev_priv->info->gen == 5) \
ilk_dummy_write(dev_priv); \
if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
if (dev_priv->uncore.forcewake_count == 0) \
dev_priv->uncore.funcs.force_wake_get(dev_priv); \
val = __raw_i915_read##x(dev_priv, reg); \
if (dev_priv->uncore.forcewake_count == 0) \
dev_priv->uncore.funcs.force_wake_put(dev_priv); \
} else { \
val = __raw_i915_read##x(dev_priv, reg); \
} \
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); \
trace_i915_reg_rw(false, reg, val, sizeof(val), trace); \
return val; \
}
__i915_read(8)
__i915_read(16)
__i915_read(32)
__i915_read(64)
#undef __i915_read
#define __i915_write(x) \
void i915_write##x(struct drm_i915_private *dev_priv, u32 reg, u##x val, bool trace) { \
unsigned long irqflags; \
u32 __fifo_ret = 0; \
trace_i915_reg_rw(true, reg, val, sizeof(val), trace); \
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); \
if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
__fifo_ret = __gen6_gt_wait_for_fifo(dev_priv); \
} \
if (dev_priv->info->gen == 5) \
ilk_dummy_write(dev_priv); \
hsw_unclaimed_reg_clear(dev_priv, reg); \
__raw_i915_write##x(dev_priv, reg, val); \
if (unlikely(__fifo_ret)) { \
gen6_gt_check_fifodbg(dev_priv); \
} \
hsw_unclaimed_reg_check(dev_priv, reg); \
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); \
}
__i915_write(8)
__i915_write(16)
__i915_write(32)
__i915_write(64)
#undef __i915_write
static const struct register_whitelist {
uint64_t offset;
uint32_t size;
uint32_t gen_bitmask; /* support gens, 0x10 for 4, 0x30 for 4 and 5, etc. */
} whitelist[] = {
{ RING_TIMESTAMP(RENDER_RING_BASE), 8, 0xF0 },
};
int i915_reg_read_ioctl(struct drm_device *dev,
void *data, struct drm_file *file)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_i915_reg_read *reg = data;
struct register_whitelist const *entry = whitelist;
int i;
for (i = 0; i < ARRAY_SIZE(whitelist); i++, entry++) {
if (entry->offset == reg->offset &&
(1 << INTEL_INFO(dev)->gen & entry->gen_bitmask))
break;
}
if (i == ARRAY_SIZE(whitelist))
return -EINVAL;
switch (entry->size) {
case 8:
reg->val = I915_READ64(reg->offset);
break;
case 4:
reg->val = I915_READ(reg->offset);
break;
case 2:
reg->val = I915_READ16(reg->offset);
break;
case 1:
reg->val = I915_READ8(reg->offset);
break;
default:
WARN_ON(1);
return -EINVAL;
}
return 0;
}
static int i8xx_do_reset(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (IS_I85X(dev))
return -ENODEV;
I915_WRITE(D_STATE, I915_READ(D_STATE) | DSTATE_GFX_RESET_I830);
POSTING_READ(D_STATE);
if (IS_I830(dev) || IS_845G(dev)) {
I915_WRITE(DEBUG_RESET_I830,
DEBUG_RESET_DISPLAY |
DEBUG_RESET_RENDER |
DEBUG_RESET_FULL);
POSTING_READ(DEBUG_RESET_I830);
msleep(1);
I915_WRITE(DEBUG_RESET_I830, 0);
POSTING_READ(DEBUG_RESET_I830);
}
msleep(1);
I915_WRITE(D_STATE, I915_READ(D_STATE) & ~DSTATE_GFX_RESET_I830);
POSTING_READ(D_STATE);
return 0;
}
static int i965_reset_complete(struct drm_device *dev)
{
u8 gdrst;
pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst);
return (gdrst & GRDOM_RESET_ENABLE) == 0;
}
static int i965_do_reset(struct drm_device *dev)
{
int ret;
/*
* Set the domains we want to reset (GRDOM/bits 2 and 3) as
* well as the reset bit (GR/bit 0). Setting the GR bit
* triggers the reset; when done, the hardware will clear it.
*/
pci_write_config_byte(dev->pdev, I965_GDRST,
GRDOM_RENDER | GRDOM_RESET_ENABLE);
ret = wait_for(i965_reset_complete(dev), 500);
if (ret)
return ret;
/* We can't reset render&media without also resetting display ... */
pci_write_config_byte(dev->pdev, I965_GDRST,
GRDOM_MEDIA | GRDOM_RESET_ENABLE);
ret = wait_for(i965_reset_complete(dev), 500);
if (ret)
return ret;
pci_write_config_byte(dev->pdev, I965_GDRST, 0);
return 0;
}
static int ironlake_do_reset(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u32 gdrst;
int ret;
gdrst = I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR);
gdrst &= ~GRDOM_MASK;
I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR,
gdrst | GRDOM_RENDER | GRDOM_RESET_ENABLE);
ret = wait_for(I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) & 0x1, 500);
if (ret)
return ret;
/* We can't reset render&media without also resetting display ... */
gdrst = I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR);
gdrst &= ~GRDOM_MASK;
I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR,
gdrst | GRDOM_MEDIA | GRDOM_RESET_ENABLE);
return wait_for(I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) & 0x1, 500);
}
static int gen6_do_reset(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
int ret;
unsigned long irqflags;
/* Hold uncore.lock across reset to prevent any register access
* with forcewake not set correctly
*/
spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
/* Reset the chip */
/* GEN6_GDRST is not in the gt power well, no need to check
* for fifo space for the write or forcewake the chip for
* the read
*/
__raw_i915_write32(dev_priv, GEN6_GDRST, GEN6_GRDOM_FULL);
/* Spin waiting for the device to ack the reset request */
ret = wait_for((__raw_i915_read32(dev_priv, GEN6_GDRST) & GEN6_GRDOM_FULL) == 0, 500);
intel_uncore_forcewake_reset(dev);
/* If reset with a user forcewake, try to restore, otherwise turn it off */
if (dev_priv->uncore.forcewake_count)
dev_priv->uncore.funcs.force_wake_get(dev_priv);
else
dev_priv->uncore.funcs.force_wake_put(dev_priv);
/* Restore fifo count */
dev_priv->uncore.fifo_count = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
return ret;
}
int intel_gpu_reset(struct drm_device *dev)
{
switch (INTEL_INFO(dev)->gen) {
case 7:
case 6: return gen6_do_reset(dev);
case 5: return ironlake_do_reset(dev);
case 4: return i965_do_reset(dev);
case 2: return i8xx_do_reset(dev);
default: return -ENODEV;
}
}
void intel_uncore_clear_errors(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
/* XXX needs spinlock around caller's grouping */
if (HAS_FPGA_DBG_UNCLAIMED(dev))
__raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
}
void intel_uncore_check_errors(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (HAS_FPGA_DBG_UNCLAIMED(dev) &&
(__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
DRM_ERROR("Unclaimed register before interrupt\n");
__raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
}
}