linux_dsm_epyc7002/drivers/gpu/drm/vmwgfx/vmwgfx_irq.c
Thomas Hellstrom d2e8851a90 drm/vmwgfx: Relax irq locking somewhat
Relax locking with the goal of reducing the number of locking cycles and
time spent with irqs disabled.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
2015-11-06 16:15:40 +01:00

314 lines
8.2 KiB
C

/**************************************************************************
*
* Copyright © 2009-2015 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
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* 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,
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**************************************************************************/
#include <drm/drmP.h>
#include "vmwgfx_drv.h"
#define VMW_FENCE_WRAP (1 << 24)
irqreturn_t vmw_irq_handler(int irq, void *arg)
{
struct drm_device *dev = (struct drm_device *)arg;
struct vmw_private *dev_priv = vmw_priv(dev);
uint32_t status, masked_status;
status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
masked_status = status & READ_ONCE(dev_priv->irq_mask);
if (likely(status))
outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
if (!status)
return IRQ_NONE;
if (masked_status & (SVGA_IRQFLAG_ANY_FENCE |
SVGA_IRQFLAG_FENCE_GOAL)) {
vmw_fences_update(dev_priv->fman);
wake_up_all(&dev_priv->fence_queue);
}
if (masked_status & SVGA_IRQFLAG_FIFO_PROGRESS)
wake_up_all(&dev_priv->fifo_queue);
if (masked_status & (SVGA_IRQFLAG_COMMAND_BUFFER |
SVGA_IRQFLAG_ERROR))
vmw_cmdbuf_tasklet_schedule(dev_priv->cman);
return IRQ_HANDLED;
}
static bool vmw_fifo_idle(struct vmw_private *dev_priv, uint32_t seqno)
{
return (vmw_read(dev_priv, SVGA_REG_BUSY) == 0);
}
void vmw_update_seqno(struct vmw_private *dev_priv,
struct vmw_fifo_state *fifo_state)
{
u32 *fifo_mem = dev_priv->mmio_virt;
uint32_t seqno = vmw_mmio_read(fifo_mem + SVGA_FIFO_FENCE);
if (dev_priv->last_read_seqno != seqno) {
dev_priv->last_read_seqno = seqno;
vmw_marker_pull(&fifo_state->marker_queue, seqno);
vmw_fences_update(dev_priv->fman);
}
}
bool vmw_seqno_passed(struct vmw_private *dev_priv,
uint32_t seqno)
{
struct vmw_fifo_state *fifo_state;
bool ret;
if (likely(dev_priv->last_read_seqno - seqno < VMW_FENCE_WRAP))
return true;
fifo_state = &dev_priv->fifo;
vmw_update_seqno(dev_priv, fifo_state);
if (likely(dev_priv->last_read_seqno - seqno < VMW_FENCE_WRAP))
return true;
if (!(fifo_state->capabilities & SVGA_FIFO_CAP_FENCE) &&
vmw_fifo_idle(dev_priv, seqno))
return true;
/**
* Then check if the seqno is higher than what we've actually
* emitted. Then the fence is stale and signaled.
*/
ret = ((atomic_read(&dev_priv->marker_seq) - seqno)
> VMW_FENCE_WRAP);
return ret;
}
int vmw_fallback_wait(struct vmw_private *dev_priv,
bool lazy,
bool fifo_idle,
uint32_t seqno,
bool interruptible,
unsigned long timeout)
{
struct vmw_fifo_state *fifo_state = &dev_priv->fifo;
uint32_t count = 0;
uint32_t signal_seq;
int ret;
unsigned long end_jiffies = jiffies + timeout;
bool (*wait_condition)(struct vmw_private *, uint32_t);
DEFINE_WAIT(__wait);
wait_condition = (fifo_idle) ? &vmw_fifo_idle :
&vmw_seqno_passed;
/**
* Block command submission while waiting for idle.
*/
if (fifo_idle) {
down_read(&fifo_state->rwsem);
if (dev_priv->cman) {
ret = vmw_cmdbuf_idle(dev_priv->cman, interruptible,
10*HZ);
if (ret)
goto out_err;
}
}
signal_seq = atomic_read(&dev_priv->marker_seq);
ret = 0;
for (;;) {
prepare_to_wait(&dev_priv->fence_queue, &__wait,
(interruptible) ?
TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
if (wait_condition(dev_priv, seqno))
break;
if (time_after_eq(jiffies, end_jiffies)) {
DRM_ERROR("SVGA device lockup.\n");
break;
}
if (lazy)
schedule_timeout(1);
else if ((++count & 0x0F) == 0) {
/**
* FIXME: Use schedule_hr_timeout here for
* newer kernels and lower CPU utilization.
*/
__set_current_state(TASK_RUNNING);
schedule();
__set_current_state((interruptible) ?
TASK_INTERRUPTIBLE :
TASK_UNINTERRUPTIBLE);
}
if (interruptible && signal_pending(current)) {
ret = -ERESTARTSYS;
break;
}
}
finish_wait(&dev_priv->fence_queue, &__wait);
if (ret == 0 && fifo_idle) {
u32 *fifo_mem = dev_priv->mmio_virt;
vmw_mmio_write(signal_seq, fifo_mem + SVGA_FIFO_FENCE);
}
wake_up_all(&dev_priv->fence_queue);
out_err:
if (fifo_idle)
up_read(&fifo_state->rwsem);
return ret;
}
void vmw_generic_waiter_add(struct vmw_private *dev_priv,
u32 flag, int *waiter_count)
{
spin_lock_bh(&dev_priv->waiter_lock);
if ((*waiter_count)++ == 0) {
outl(flag, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
dev_priv->irq_mask |= flag;
vmw_write(dev_priv, SVGA_REG_IRQMASK, dev_priv->irq_mask);
}
spin_unlock_bh(&dev_priv->waiter_lock);
}
void vmw_generic_waiter_remove(struct vmw_private *dev_priv,
u32 flag, int *waiter_count)
{
spin_lock_bh(&dev_priv->waiter_lock);
if (--(*waiter_count) == 0) {
dev_priv->irq_mask &= ~flag;
vmw_write(dev_priv, SVGA_REG_IRQMASK, dev_priv->irq_mask);
}
spin_unlock_bh(&dev_priv->waiter_lock);
}
void vmw_seqno_waiter_add(struct vmw_private *dev_priv)
{
vmw_generic_waiter_add(dev_priv, SVGA_IRQFLAG_ANY_FENCE,
&dev_priv->fence_queue_waiters);
}
void vmw_seqno_waiter_remove(struct vmw_private *dev_priv)
{
vmw_generic_waiter_remove(dev_priv, SVGA_IRQFLAG_ANY_FENCE,
&dev_priv->fence_queue_waiters);
}
void vmw_goal_waiter_add(struct vmw_private *dev_priv)
{
vmw_generic_waiter_add(dev_priv, SVGA_IRQFLAG_FENCE_GOAL,
&dev_priv->goal_queue_waiters);
}
void vmw_goal_waiter_remove(struct vmw_private *dev_priv)
{
vmw_generic_waiter_remove(dev_priv, SVGA_IRQFLAG_FENCE_GOAL,
&dev_priv->goal_queue_waiters);
}
int vmw_wait_seqno(struct vmw_private *dev_priv,
bool lazy, uint32_t seqno,
bool interruptible, unsigned long timeout)
{
long ret;
struct vmw_fifo_state *fifo = &dev_priv->fifo;
if (likely(dev_priv->last_read_seqno - seqno < VMW_FENCE_WRAP))
return 0;
if (likely(vmw_seqno_passed(dev_priv, seqno)))
return 0;
vmw_fifo_ping_host(dev_priv, SVGA_SYNC_GENERIC);
if (!(fifo->capabilities & SVGA_FIFO_CAP_FENCE))
return vmw_fallback_wait(dev_priv, lazy, true, seqno,
interruptible, timeout);
if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
return vmw_fallback_wait(dev_priv, lazy, false, seqno,
interruptible, timeout);
vmw_seqno_waiter_add(dev_priv);
if (interruptible)
ret = wait_event_interruptible_timeout
(dev_priv->fence_queue,
vmw_seqno_passed(dev_priv, seqno),
timeout);
else
ret = wait_event_timeout
(dev_priv->fence_queue,
vmw_seqno_passed(dev_priv, seqno),
timeout);
vmw_seqno_waiter_remove(dev_priv);
if (unlikely(ret == 0))
ret = -EBUSY;
else if (likely(ret > 0))
ret = 0;
return ret;
}
void vmw_irq_preinstall(struct drm_device *dev)
{
struct vmw_private *dev_priv = vmw_priv(dev);
uint32_t status;
if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
return;
status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
}
int vmw_irq_postinstall(struct drm_device *dev)
{
return 0;
}
void vmw_irq_uninstall(struct drm_device *dev)
{
struct vmw_private *dev_priv = vmw_priv(dev);
uint32_t status;
if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
return;
vmw_write(dev_priv, SVGA_REG_IRQMASK, 0);
status = inl(dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
outl(status, dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
}