xref: /openbmc/linux/drivers/iommu/msm_iommu.h (revision aac5987a)
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/iommu.h>
23 #include <linux/clk.h>
24 
25 /* Sharability attributes of MSM IOMMU mappings */
26 #define MSM_IOMMU_ATTR_NON_SH		0x0
27 #define MSM_IOMMU_ATTR_SH		0x4
28 
29 /* Cacheability attributes of MSM IOMMU mappings */
30 #define MSM_IOMMU_ATTR_NONCACHED	0x0
31 #define MSM_IOMMU_ATTR_CACHED_WB_WA	0x1
32 #define MSM_IOMMU_ATTR_CACHED_WB_NWA	0x2
33 #define MSM_IOMMU_ATTR_CACHED_WT	0x3
34 
35 /* Mask for the cache policy attribute */
36 #define MSM_IOMMU_CP_MASK		0x03
37 
38 /* Maximum number of Machine IDs that we are allowing to be mapped to the same
39  * context bank. The number of MIDs mapped to the same CB does not affect
40  * performance, but there is a practical limit on how many distinct MIDs may
41  * be present. These mappings are typically determined at design time and are
42  * not expected to change at run time.
43  */
44 #define MAX_NUM_MIDS	32
45 
46 /* Maximum number of context banks that can be present in IOMMU */
47 #define IOMMU_MAX_CBS	128
48 
49 /**
50  * struct msm_iommu_dev - a single IOMMU hardware instance
51  * ncb		Number of context banks present on this IOMMU HW instance
52  * dev:		IOMMU device
53  * irq:		Interrupt number
54  * clk:		The bus clock for this IOMMU hardware instance
55  * pclk:	The clock for the IOMMU bus interconnect
56  * dev_node:	list head in qcom_iommu_device_list
57  * dom_node:	list head for domain
58  * ctx_list:	list of 'struct msm_iommu_ctx_dev'
59  * context_map: Bitmap to track allocated context banks
60  */
61 struct msm_iommu_dev {
62 	void __iomem *base;
63 	int ncb;
64 	struct device *dev;
65 	int irq;
66 	struct clk *clk;
67 	struct clk *pclk;
68 	struct list_head dev_node;
69 	struct list_head dom_node;
70 	struct list_head ctx_list;
71 	DECLARE_BITMAP(context_map, IOMMU_MAX_CBS);
72 
73 	struct iommu_device iommu;
74 };
75 
76 /**
77  * struct msm_iommu_ctx_dev - an IOMMU context bank instance
78  * of_node	node ptr of client device
79  * num		Index of this context bank within the hardware
80  * mids		List of Machine IDs that are to be mapped into this context
81  *		bank, terminated by -1. The MID is a set of signals on the
82  *		AXI bus that identifies the function associated with a specific
83  *		memory request. (See ARM spec).
84  * num_mids	Total number of mids
85  * node		list head in ctx_list
86  */
87 struct msm_iommu_ctx_dev {
88 	struct device_node *of_node;
89 	int num;
90 	int mids[MAX_NUM_MIDS];
91 	int num_mids;
92 	struct list_head list;
93 };
94 
95 /*
96  * Interrupt handler for the IOMMU context fault interrupt. Hooking the
97  * interrupt is not supported in the API yet, but this will print an error
98  * message and dump useful IOMMU registers.
99  */
100 irqreturn_t msm_iommu_fault_handler(int irq, void *dev_id);
101 
102 #endif
103