Commit df12d1c3 authored by Michal Wajdeczko's avatar Michal Wajdeczko Committed by Daniel Vetter
Browse files

drm/i915/guc: Update sizes of CTB buffers 



Future GuC will require CTB buffers sizes to be multiple of 4K.
Make these changes now as this shouldn't impact us too much.

Signed-off-by: default avatarMichal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Cc: John Harrison <john.c.harrison@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603230408.54856-2-matthew.brost@intel.com
parent b43f0fc8

drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c

+32 −28
Original line number Diff line number Diff line
@@ -38,6 +38,32 @@ static inline struct drm_device *ct_to_drm(struct intel_guc_ct *ct) 
#define CT_PROBE_ERROR(_ct, _fmt, ...) \

	i915_probe_error(ct_to_i915(ct), "CT: " _fmt, ##__VA_ARGS__)



/**

 * DOC: CTB Blob

 *

 * We allocate single blob to hold both CTB descriptors and buffers:

 *

 *      +--------+-----------------------------------------------+------+

 *      | offset | contents                                      | size |

 *      +========+===============================================+======+

 *      | 0x0000 | H2G `CTB Descriptor`_ (send)                  |      |

 *      +--------+-----------------------------------------------+  4K  |

 *      | 0x0800 | G2H `CTB Descriptor`_ (recv)                  |      |

 *      +--------+-----------------------------------------------+------+

 *      | 0x1000 | H2G `CT Buffer`_ (send)                       | n*4K |

 *      |        |                                               |      |

 *      +--------+-----------------------------------------------+------+

 *      | 0x1000 | G2H `CT Buffer`_ (recv)                       | m*4K |

 *      | + n*4K |                                               |      |

 *      +--------+-----------------------------------------------+------+

 *

 * Size of each `CT Buffer`_ must be multiple of 4K.

 * As we don't expect too many messages, for now use minimum sizes.

 */

#define CTB_DESC_SIZE		ALIGN(sizeof(struct guc_ct_buffer_desc), SZ_2K)

#define CTB_H2G_BUFFER_SIZE	(SZ_4K)

#define CTB_G2H_BUFFER_SIZE	(SZ_4K)



struct ct_request {

	struct list_head link;

	u32 fence;
@@ -175,29 +201,7 @@ int intel_guc_ct_init(struct intel_guc_ct *ct) 


	GEM_BUG_ON(ct->vma);



	/* We allocate 1 page to hold both descriptors and both buffers.

	 *       ___________.....................

	 *      |desc (SEND)|                   :

	 *      |___________|                   PAGE/4

	 *      :___________....................:

	 *      |desc (RECV)|                   :

	 *      |___________|                   PAGE/4

	 *      :_______________________________:

	 *      |cmds (SEND)                    |

	 *      |                               PAGE/4

	 *      |_______________________________|

	 *      |cmds (RECV)                    |

	 *      |                               PAGE/4

	 *      |_______________________________|

	 *

	 * Each message can use a maximum of 32 dwords and we don't expect to

	 * have more than 1 in flight at any time, so we have enough space.

	 * Some logic further ahead will rely on the fact that there is only 1

	 * page and that it is always mapped, so if the size is changed the

	 * other code will need updating as well.

	 */



	blob_size = PAGE_SIZE;

	blob_size = 2 * CTB_DESC_SIZE + CTB_H2G_BUFFER_SIZE + CTB_G2H_BUFFER_SIZE;

	err = intel_guc_allocate_and_map_vma(guc, blob_size, &ct->vma, &blob);

	if (unlikely(err)) {

		CT_PROBE_ERROR(ct, "Failed to allocate %u for CTB data (%pe)\n",
@@ -209,17 +213,17 @@ int intel_guc_ct_init(struct intel_guc_ct *ct) 


	/* store pointers to desc and cmds for send ctb */

	desc = blob;

	cmds = blob + PAGE_SIZE / 2;

	cmds_size = PAGE_SIZE / 4;

	cmds = blob + 2 * CTB_DESC_SIZE;

	cmds_size = CTB_H2G_BUFFER_SIZE;

	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "send",

		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);



	guc_ct_buffer_init(&ct->ctbs.send, desc, cmds, cmds_size);



	/* store pointers to desc and cmds for recv ctb */

	desc = blob + PAGE_SIZE / 4;

	cmds = blob + PAGE_SIZE / 4 + PAGE_SIZE / 2;

	cmds_size = PAGE_SIZE / 4;

	desc = blob + CTB_DESC_SIZE;

	cmds = blob + 2 * CTB_DESC_SIZE + CTB_H2G_BUFFER_SIZE;

	cmds_size = CTB_G2H_BUFFER_SIZE;

	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "recv",

		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);