drm/omap: DMM/TILER support for OMAP4+ platform

Dynamic Memory Manager (DMM) is a hardware block in the OMAP4+
processor that contains at least one TILER instance.  TILER, or
Tiling and Isometric Lightweight Engine for Rotation, provides
IOMMU capabilities through the use of a physical address translation
table.  The TILER also provides zero cost rotation and mirroring.

The TILER provides both 1D and 2D access by providing different views
or address ranges that can be used to access the physical memory that
has been mapped in through the PAT.  Access to the 1D view results in
linear access to the underlying memory.  Access to the 2D views result
in tiled access to the underlying memory resulted in increased
efficiency.

The TILER address space is managed by a tiler container manager (TCM)
and allocates the address space through the use of the Simple Tiler
Allocation algorithm (SiTA).  The purpose of the algorithm is to keep
fragmentation of the address space as low as possible.

Signed-off-by: Andy Gross <andy.gross@ti.com>
Signed-off-by: Rob Clark <rob@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 95 insertions, 0 deletions

diff --git a/drivers/staging/omapdrm/tcm-sita.h b/drivers/staging/omapdrm/tcm-sita.h
new file mode 100644
index 000000000000..0444f868671c
--- /dev/null
+++ b/drivers/staging/omapdrm/tcm-sita.h
@@ -0,0 +1,95 @@
+/*
+ * tcm_sita.h
+ *
+ * SImple Tiler Allocator (SiTA) private structures.
+ *
+ * Author: Ravi Ramachandra <r.ramachandra@ti.com>
+ *
+ * Copyright (C) 2009-2011 Texas Instruments, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of Texas Instruments Incorporated nor the names of
+ *   its contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _TCM_SITA_H
+#define _TCM_SITA_H
+
+#include "tcm.h"
+
+/* length between two coordinates */
+#define LEN(a, b) ((a) > (b) ? (a) - (b) + 1 : (b) - (a) + 1)
+
+enum criteria {
+	CR_MAX_NEIGHS		= 0x01,
+	CR_FIRST_FOUND		= 0x10,
+	CR_BIAS_HORIZONTAL	= 0x20,
+	CR_BIAS_VERTICAL	= 0x40,
+	CR_DIAGONAL_BALANCE	= 0x80
+};
+
+/* nearness to the beginning of the search field from 0 to 1000 */
+struct nearness_factor {
+	s32 x;
+	s32 y;
+};
+
+/*
+ * Statistics on immediately neighboring slots.  Edge is the number of
+ * border segments that are also border segments of the scan field.  Busy
+ * refers to the number of neighbors that are occupied.
+ */
+struct neighbor_stats {
+	u16 edge;
+	u16 busy;
+};
+
+/* structure to keep the score of a potential allocation */
+struct score {
+	struct nearness_factor	f;
+	struct neighbor_stats	n;
+	struct tcm_area		a;
+	u16    neighs;		/* number of busy neighbors */
+};
+
+struct sita_pvt {
+	spinlock_t lock;	/* spinlock to protect access */
+	struct tcm_pt div_pt;	/* divider point splitting container */
+	struct tcm_area ***map;	/* pointers to the parent area for each slot */
+};
+
+/* assign coordinates to area */
+static inline
+void assign(struct tcm_area *a, u16 x0, u16 y0, u16 x1, u16 y1)
+{
+	a->p0.x = x0;
+	a->p0.y = y0;
+	a->p1.x = x1;
+	a->p1.y = y1;
+}
+
+#endif