1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   *  linux/include/amba/bus.h
4   *
5   *  This device type deals with ARM PrimeCells and anything else that
6   *  presents a proper CID (0xB105F00D) at the end of the I/O register
7   *  region or that is derived from a PrimeCell.
8   *
9   *  Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
10   */
11  #ifndef ASMARM_AMBA_H
12  #define ASMARM_AMBA_H
13  
14  #include <linux/clk.h>
15  #include <linux/device.h>
16  #include <linux/mod_devicetable.h>
17  #include <linux/err.h>
18  #include <linux/resource.h>
19  #include <linux/regulator/consumer.h>
20  
21  #define AMBA_NR_IRQS	9
22  #define AMBA_CID	0xb105f00d
23  #define CORESIGHT_CID	0xb105900d
24  
25  /*
26   * CoreSight Architecture specification updates the ID specification
27   * for components on the AMBA bus. (ARM IHI 0029E)
28   *
29   * Bits 15:12 of the CID are the device class.
30   *
31   * Class 0xF remains for PrimeCell and legacy components. (AMBA_CID above)
32   * Class 0x9 defines the component as CoreSight (CORESIGHT_CID above)
33   * Class 0x0, 0x1, 0xB, 0xE define components that do not have driver support
34   * at present.
35   * Class 0x2-0x8,0xA and 0xD-0xD are presently reserved.
36   *
37   * Remaining CID bits stay as 0xb105-00d
38   */
39  
40  /**
41   * Class 0x9 components use additional values to form a Unique Component
42   * Identifier (UCI), where peripheral ID values are identical for different
43   * components. Passed to the amba bus code from the component driver via
44   * the amba_id->data pointer.
45   * @devarch	: coresight devarch register value
46   * @devarch_mask: mask bits used for matching. 0 indicates UCI not used.
47   * @devtype	: coresight device type value
48   * @data	: additional driver data. As we have usurped the original
49   *		pointer some devices may still need additional data
50   */
51  struct amba_cs_uci_id {
52  	unsigned int devarch;
53  	unsigned int devarch_mask;
54  	unsigned int devtype;
55  	void *data;
56  };
57  
58  /* define offsets for registers used by UCI */
59  #define UCI_REG_DEVTYPE_OFFSET	0xFCC
60  #define UCI_REG_DEVARCH_OFFSET	0xFBC
61  
62  struct clk;
63  
64  struct amba_device {
65  	struct device		dev;
66  	struct resource		res;
67  	struct clk		*pclk;
68  	struct device_dma_parameters dma_parms;
69  	unsigned int		periphid;
70  	struct mutex		periphid_lock;
71  	unsigned int		cid;
72  	struct amba_cs_uci_id	uci;
73  	unsigned int		irq[AMBA_NR_IRQS];
74  	/*
75  	 * Driver name to force a match.  Do not set directly, because core
76  	 * frees it.  Use driver_set_override() to set or clear it.
77  	 */
78  	const char		*driver_override;
79  };
80  
81  struct amba_driver {
82  	struct device_driver	drv;
83  	int			(*probe)(struct amba_device *, const struct amba_id *);
84  	void			(*remove)(struct amba_device *);
85  	void			(*shutdown)(struct amba_device *);
86  	const struct amba_id	*id_table;
87  	/*
88  	 * For most device drivers, no need to care about this flag as long as
89  	 * all DMAs are handled through the kernel DMA API. For some special
90  	 * ones, for example VFIO drivers, they know how to manage the DMA
91  	 * themselves and set this flag so that the IOMMU layer will allow them
92  	 * to setup and manage their own I/O address space.
93  	 */
94  	bool driver_managed_dma;
95  };
96  
97  /*
98   * Constants for the designer field of the Peripheral ID register. When bit 7
99   * is set to '1', bits [6:0] should be the JEP106 manufacturer identity code.
100   */
101  enum amba_vendor {
102  	AMBA_VENDOR_ARM = 0x41,
103  	AMBA_VENDOR_ST = 0x80,
104  	AMBA_VENDOR_QCOM = 0x51,
105  	AMBA_VENDOR_LSI = 0xb6,
106  };
107  
108  extern const struct bus_type amba_bustype;
109  
110  #define to_amba_device(d)	container_of_const(d, struct amba_device, dev)
111  
112  #define amba_get_drvdata(d)	dev_get_drvdata(&d->dev)
113  #define amba_set_drvdata(d,p)	dev_set_drvdata(&d->dev, p)
114  
115  /*
116   * use a macro to avoid include chaining to get THIS_MODULE
117   */
118  #define amba_driver_register(drv) \
119  	__amba_driver_register(drv, THIS_MODULE)
120  
121  #ifdef CONFIG_ARM_AMBA
122  int __amba_driver_register(struct amba_driver *, struct module *);
123  void amba_driver_unregister(struct amba_driver *);
124  #else
__amba_driver_register(struct amba_driver * drv,struct module * owner)125  static inline int __amba_driver_register(struct amba_driver *drv,
126  					 struct module *owner)
127  {
128  	return -EINVAL;
129  }
amba_driver_unregister(struct amba_driver * drv)130  static inline void amba_driver_unregister(struct amba_driver *drv)
131  {
132  }
133  #endif
134  
135  struct amba_device *amba_device_alloc(const char *, resource_size_t, size_t);
136  void amba_device_put(struct amba_device *);
137  int amba_device_add(struct amba_device *, struct resource *);
138  int amba_device_register(struct amba_device *, struct resource *);
139  void amba_device_unregister(struct amba_device *);
140  int amba_request_regions(struct amba_device *, const char *);
141  void amba_release_regions(struct amba_device *);
142  
143  /* Some drivers don't use the struct amba_device */
144  #define AMBA_CONFIG_BITS(a) (((a) >> 24) & 0xff)
145  #define AMBA_REV_BITS(a) (((a) >> 20) & 0x0f)
146  #define AMBA_MANF_BITS(a) (((a) >> 12) & 0xff)
147  #define AMBA_PART_BITS(a) ((a) & 0xfff)
148  
149  #define amba_config(d)	AMBA_CONFIG_BITS((d)->periphid)
150  #define amba_rev(d)	AMBA_REV_BITS((d)->periphid)
151  #define amba_manf(d)	AMBA_MANF_BITS((d)->periphid)
152  #define amba_part(d)	AMBA_PART_BITS((d)->periphid)
153  
154  #define __AMBA_DEV(busid, data, mask)				\
155  	{							\
156  		.coherent_dma_mask = mask,			\
157  		.init_name = busid,				\
158  		.platform_data = data,				\
159  	}
160  
161  /*
162   * APB devices do not themselves have the ability to address memory,
163   * so DMA masks should be zero (much like USB peripheral devices.)
164   * The DMA controller DMA masks should be used instead (much like
165   * USB host controllers in conventional PCs.)
166   */
167  #define AMBA_APB_DEVICE(name, busid, id, base, irqs, data)	\
168  struct amba_device name##_device = {				\
169  	.dev = __AMBA_DEV(busid, data, 0),			\
170  	.res = DEFINE_RES_MEM(base, SZ_4K),			\
171  	.irq = irqs,						\
172  	.periphid = id,						\
173  }
174  
175  /*
176   * AHB devices are DMA capable, so set their DMA masks
177   */
178  #define AMBA_AHB_DEVICE(name, busid, id, base, irqs, data)	\
179  struct amba_device name##_device = {				\
180  	.dev = __AMBA_DEV(busid, data, ~0ULL),			\
181  	.res = DEFINE_RES_MEM(base, SZ_4K),			\
182  	.irq = irqs,						\
183  	.periphid = id,						\
184  }
185  
186  /*
187   * module_amba_driver() - Helper macro for drivers that don't do anything
188   * special in module init/exit.  This eliminates a lot of boilerplate.  Each
189   * module may only use this macro once, and calling it replaces module_init()
190   * and module_exit()
191   */
192  #define module_amba_driver(__amba_drv) \
193  	module_driver(__amba_drv, amba_driver_register, amba_driver_unregister)
194  
195  /*
196   * builtin_amba_driver() - Helper macro for drivers that don't do anything
197   * special in driver initcall.  This eliminates a lot of boilerplate.  Each
198   * driver may only use this macro once, and calling it replaces the instance
199   * device_initcall().
200   */
201  #define builtin_amba_driver(__amba_drv) \
202  	builtin_driver(__amba_drv, amba_driver_register)
203  
204  #endif
205