xref: /openbmc/linux/drivers/iommu/msm_iommu.h (revision 9cfc5c90)
1 /* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program; if not, write to the Free Software
14  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15  * 02110-1301, USA.
16  */
17 
18 #ifndef MSM_IOMMU_H
19 #define MSM_IOMMU_H
20 
21 #include <linux/interrupt.h>
22 #include <linux/clk.h>
23 
24 /* Sharability attributes of MSM IOMMU mappings */
25 #define MSM_IOMMU_ATTR_NON_SH		0x0
26 #define MSM_IOMMU_ATTR_SH		0x4
27 
28 /* Cacheability attributes of MSM IOMMU mappings */
29 #define MSM_IOMMU_ATTR_NONCACHED	0x0
30 #define MSM_IOMMU_ATTR_CACHED_WB_WA	0x1
31 #define MSM_IOMMU_ATTR_CACHED_WB_NWA	0x2
32 #define MSM_IOMMU_ATTR_CACHED_WT	0x3
33 
34 /* Mask for the cache policy attribute */
35 #define MSM_IOMMU_CP_MASK		0x03
36 
37 /* Maximum number of Machine IDs that we are allowing to be mapped to the same
38  * context bank. The number of MIDs mapped to the same CB does not affect
39  * performance, but there is a practical limit on how many distinct MIDs may
40  * be present. These mappings are typically determined at design time and are
41  * not expected to change at run time.
42  */
43 #define MAX_NUM_MIDS	32
44 
45 /**
46  * struct msm_iommu_dev - a single IOMMU hardware instance
47  * name		Human-readable name given to this IOMMU HW instance
48  * ncb		Number of context banks present on this IOMMU HW instance
49  */
50 struct msm_iommu_dev {
51 	const char *name;
52 	int ncb;
53 };
54 
55 /**
56  * struct msm_iommu_ctx_dev - an IOMMU context bank instance
57  * name		Human-readable name given to this context bank
58  * num		Index of this context bank within the hardware
59  * mids		List of Machine IDs that are to be mapped into this context
60  *		bank, terminated by -1. The MID is a set of signals on the
61  *		AXI bus that identifies the function associated with a specific
62  *		memory request. (See ARM spec).
63  */
64 struct msm_iommu_ctx_dev {
65 	const char *name;
66 	int num;
67 	int mids[MAX_NUM_MIDS];
68 };
69 
70 
71 /**
72  * struct msm_iommu_drvdata - A single IOMMU hardware instance
73  * @base:	IOMMU config port base address (VA)
74  * @ncb		The number of contexts on this IOMMU
75  * @irq:	Interrupt number
76  * @clk:	The bus clock for this IOMMU hardware instance
77  * @pclk:	The clock for the IOMMU bus interconnect
78  *
79  * A msm_iommu_drvdata holds the global driver data about a single piece
80  * of an IOMMU hardware instance.
81  */
82 struct msm_iommu_drvdata {
83 	void __iomem *base;
84 	int irq;
85 	int ncb;
86 	struct clk *clk;
87 	struct clk *pclk;
88 };
89 
90 /**
91  * struct msm_iommu_ctx_drvdata - an IOMMU context bank instance
92  * @num:		Hardware context number of this context
93  * @pdev:		Platform device associated wit this HW instance
94  * @attached_elm:	List element for domains to track which devices are
95  *			attached to them
96  *
97  * A msm_iommu_ctx_drvdata holds the driver data for a single context bank
98  * within each IOMMU hardware instance
99  */
100 struct msm_iommu_ctx_drvdata {
101 	int num;
102 	struct platform_device *pdev;
103 	struct list_head attached_elm;
104 };
105 
106 /*
107  * Look up an IOMMU context device by its context name. NULL if none found.
108  * Useful for testing and drivers that do not yet fully have IOMMU stuff in
109  * their platform devices.
110  */
111 struct device *msm_iommu_get_ctx(const char *ctx_name);
112 
113 /*
114  * Interrupt handler for the IOMMU context fault interrupt. Hooking the
115  * interrupt is not supported in the API yet, but this will print an error
116  * message and dump useful IOMMU registers.
117  */
118 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id);
119 
120 #endif
121