linux/drivers/gpu/drm/i915/intel_ringbuffer.h
Ben Widawsky e055684168 drm/i915: context switch implementation
Implement the context switch code as well as the interfaces to do the
context switch. This patch also doesn't match 1:1 with the RFC patches.
The main difference is that from Daniel's responses the last context
object is now stored instead of the last context. This aids in allows us
to free the context data structure, and context object independently.

There is room for optimization: this code will pin the context object
until the next context is active. The optimal way to do it is to
actually pin the object, move it to the active list, do the context
switch, and then unpin it. This allows the eviction code to actually
evict the context object if needed.

The context switch code is missing workarounds, they will be implemented
in future patches.

v2: actually do obj->dirty=1 in switch (daniel)
Modified comment around above
Remove flags to context switch (daniel)
Move mi_set_context code to i915_gem_context.c (daniel)
Remove seqno , use lazy request instead (daniel)

v3: use i915_gem_request_next_seqno instead of
      outstanding_lazy_request (Daniel)
remove id's from trace events (Daniel)
Put the context BO in the instruction domain (Daniel)
Don't unref the BO is context switch fails (Chris)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
2012-06-14 17:36:17 +02:00

224 lines
6.4 KiB
C

#ifndef _INTEL_RINGBUFFER_H_
#define _INTEL_RINGBUFFER_H_
struct intel_hw_status_page {
u32 *page_addr;
unsigned int gfx_addr;
struct drm_i915_gem_object *obj;
};
#define I915_READ_TAIL(ring) I915_READ(RING_TAIL((ring)->mmio_base))
#define I915_WRITE_TAIL(ring, val) I915_WRITE(RING_TAIL((ring)->mmio_base), val)
#define I915_READ_START(ring) I915_READ(RING_START((ring)->mmio_base))
#define I915_WRITE_START(ring, val) I915_WRITE(RING_START((ring)->mmio_base), val)
#define I915_READ_HEAD(ring) I915_READ(RING_HEAD((ring)->mmio_base))
#define I915_WRITE_HEAD(ring, val) I915_WRITE(RING_HEAD((ring)->mmio_base), val)
#define I915_READ_CTL(ring) I915_READ(RING_CTL((ring)->mmio_base))
#define I915_WRITE_CTL(ring, val) I915_WRITE(RING_CTL((ring)->mmio_base), val)
#define I915_READ_IMR(ring) I915_READ(RING_IMR((ring)->mmio_base))
#define I915_WRITE_IMR(ring, val) I915_WRITE(RING_IMR((ring)->mmio_base), val)
#define I915_READ_NOPID(ring) I915_READ(RING_NOPID((ring)->mmio_base))
#define I915_READ_SYNC_0(ring) I915_READ(RING_SYNC_0((ring)->mmio_base))
#define I915_READ_SYNC_1(ring) I915_READ(RING_SYNC_1((ring)->mmio_base))
struct intel_ring_buffer {
const char *name;
enum intel_ring_id {
RCS = 0x0,
VCS,
BCS,
} id;
#define I915_NUM_RINGS 3
u32 mmio_base;
void __iomem *virtual_start;
struct drm_device *dev;
struct drm_i915_gem_object *obj;
u32 head;
u32 tail;
int space;
int size;
int effective_size;
struct intel_hw_status_page status_page;
/** We track the position of the requests in the ring buffer, and
* when each is retired we increment last_retired_head as the GPU
* must have finished processing the request and so we know we
* can advance the ringbuffer up to that position.
*
* last_retired_head is set to -1 after the value is consumed so
* we can detect new retirements.
*/
u32 last_retired_head;
u32 irq_refcount; /* protected by dev_priv->irq_lock */
u32 irq_enable_mask; /* bitmask to enable ring interrupt */
u32 trace_irq_seqno;
u32 sync_seqno[I915_NUM_RINGS-1];
bool __must_check (*irq_get)(struct intel_ring_buffer *ring);
void (*irq_put)(struct intel_ring_buffer *ring);
int (*init)(struct intel_ring_buffer *ring);
void (*write_tail)(struct intel_ring_buffer *ring,
u32 value);
int __must_check (*flush)(struct intel_ring_buffer *ring,
u32 invalidate_domains,
u32 flush_domains);
int (*add_request)(struct intel_ring_buffer *ring,
u32 *seqno);
u32 (*get_seqno)(struct intel_ring_buffer *ring);
int (*dispatch_execbuffer)(struct intel_ring_buffer *ring,
u32 offset, u32 length);
void (*cleanup)(struct intel_ring_buffer *ring);
int (*sync_to)(struct intel_ring_buffer *ring,
struct intel_ring_buffer *to,
u32 seqno);
u32 semaphore_register[3]; /*our mbox written by others */
u32 signal_mbox[2]; /* mboxes this ring signals to */
/**
* List of objects currently involved in rendering from the
* ringbuffer.
*
* Includes buffers having the contents of their GPU caches
* flushed, not necessarily primitives. last_rendering_seqno
* represents when the rendering involved will be completed.
*
* A reference is held on the buffer while on this list.
*/
struct list_head active_list;
/**
* List of breadcrumbs associated with GPU requests currently
* outstanding.
*/
struct list_head request_list;
/**
* List of objects currently pending a GPU write flush.
*
* All elements on this list will belong to either the
* active_list or flushing_list, last_rendering_seqno can
* be used to differentiate between the two elements.
*/
struct list_head gpu_write_list;
/**
* Do we have some not yet emitted requests outstanding?
*/
u32 outstanding_lazy_request;
wait_queue_head_t irq_queue;
struct i915_hw_context *default_context;
struct drm_i915_gem_object *last_context_obj;
void *private;
};
static inline bool
intel_ring_initialized(struct intel_ring_buffer *ring)
{
return ring->obj != NULL;
}
static inline unsigned
intel_ring_flag(struct intel_ring_buffer *ring)
{
return 1 << ring->id;
}
static inline u32
intel_ring_sync_index(struct intel_ring_buffer *ring,
struct intel_ring_buffer *other)
{
int idx;
/*
* cs -> 0 = vcs, 1 = bcs
* vcs -> 0 = bcs, 1 = cs,
* bcs -> 0 = cs, 1 = vcs.
*/
idx = (other - ring) - 1;
if (idx < 0)
idx += I915_NUM_RINGS;
return idx;
}
static inline u32
intel_read_status_page(struct intel_ring_buffer *ring,
int reg)
{
/* Ensure that the compiler doesn't optimize away the load. */
barrier();
return ring->status_page.page_addr[reg];
}
/**
* Reads a dword out of the status page, which is written to from the command
* queue by automatic updates, MI_REPORT_HEAD, MI_STORE_DATA_INDEX, or
* MI_STORE_DATA_IMM.
*
* The following dwords have a reserved meaning:
* 0x00: ISR copy, updated when an ISR bit not set in the HWSTAM changes.
* 0x04: ring 0 head pointer
* 0x05: ring 1 head pointer (915-class)
* 0x06: ring 2 head pointer (915-class)
* 0x10-0x1b: Context status DWords (GM45)
* 0x1f: Last written status offset. (GM45)
*
* The area from dword 0x20 to 0x3ff is available for driver usage.
*/
#define I915_GEM_HWS_INDEX 0x20
void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring);
int __must_check intel_wait_ring_buffer(struct intel_ring_buffer *ring, int n);
static inline int intel_wait_ring_idle(struct intel_ring_buffer *ring)
{
return intel_wait_ring_buffer(ring, ring->size - 8);
}
int __must_check intel_ring_begin(struct intel_ring_buffer *ring, int n);
static inline void intel_ring_emit(struct intel_ring_buffer *ring,
u32 data)
{
iowrite32(data, ring->virtual_start + ring->tail);
ring->tail += 4;
}
void intel_ring_advance(struct intel_ring_buffer *ring);
u32 intel_ring_get_seqno(struct intel_ring_buffer *ring);
int intel_init_render_ring_buffer(struct drm_device *dev);
int intel_init_bsd_ring_buffer(struct drm_device *dev);
int intel_init_blt_ring_buffer(struct drm_device *dev);
u32 intel_ring_get_active_head(struct intel_ring_buffer *ring);
void intel_ring_setup_status_page(struct intel_ring_buffer *ring);
static inline u32 intel_ring_get_tail(struct intel_ring_buffer *ring)
{
return ring->tail;
}
static inline void i915_trace_irq_get(struct intel_ring_buffer *ring, u32 seqno)
{
if (ring->trace_irq_seqno == 0 && ring->irq_get(ring))
ring->trace_irq_seqno = seqno;
}
/* DRI warts */
int intel_render_ring_init_dri(struct drm_device *dev, u64 start, u32 size);
#endif /* _INTEL_RINGBUFFER_H_ */