xref: /linux/drivers/i3c/master/mipi-i3c-hci/hci.h (revision 55a42f78ffd386e01a5404419f8c5ded7db70a21)
1 /* SPDX-License-Identifier: BSD-3-Clause */
2 /*
3  * Copyright (c) 2020, MIPI Alliance, Inc.
4  *
5  * Author: Nicolas Pitre <npitre@baylibre.com>
6  *
7  * Common HCI stuff
8  */
9 
10 #ifndef HCI_H
11 #define HCI_H
12 
13 #include <linux/io.h>
14 
15 /* 32-bit word aware bit and mask macros */
16 #define W0_MASK(h, l)  GENMASK((h) - 0,  (l) - 0)
17 #define W1_MASK(h, l)  GENMASK((h) - 32, (l) - 32)
18 #define W2_MASK(h, l)  GENMASK((h) - 64, (l) - 64)
19 #define W3_MASK(h, l)  GENMASK((h) - 96, (l) - 96)
20 
21 /* Same for single bit macros (trailing _ to align with W*_MASK width) */
22 #define W0_BIT_(x)  BIT((x) - 0)
23 #define W1_BIT_(x)  BIT((x) - 32)
24 #define W2_BIT_(x)  BIT((x) - 64)
25 #define W3_BIT_(x)  BIT((x) - 96)
26 
27 #define reg_read(r)		readl(hci->base_regs + (r))
28 #define reg_write(r, v)		writel(v, hci->base_regs + (r))
29 #define reg_set(r, v)		reg_write(r, reg_read(r) | (v))
30 #define reg_clear(r, v)		reg_write(r, reg_read(r) & ~(v))
31 
32 struct hci_cmd_ops;
33 
34 /* Our main structure */
35 struct i3c_hci {
36 	struct i3c_master_controller master;
37 	void __iomem *base_regs;
38 	void __iomem *DAT_regs;
39 	void __iomem *DCT_regs;
40 	void __iomem *RHS_regs;
41 	void __iomem *PIO_regs;
42 	void __iomem *EXTCAPS_regs;
43 	void __iomem *AUTOCMD_regs;
44 	void __iomem *DEBUG_regs;
45 	const struct hci_io_ops *io;
46 	void *io_data;
47 	const struct hci_cmd_ops *cmd;
48 	atomic_t next_cmd_tid;
49 	u32 caps;
50 	unsigned int quirks;
51 	unsigned int DAT_entries;
52 	unsigned int DAT_entry_size;
53 	void *DAT_data;
54 	unsigned int DCT_entries;
55 	unsigned int DCT_entry_size;
56 	u8 version_major;
57 	u8 version_minor;
58 	u8 revision;
59 	u32 vendor_mipi_id;
60 	u32 vendor_version_id;
61 	u32 vendor_product_id;
62 	void *vendor_data;
63 };
64 
65 
66 /*
67  * Structure to represent a master initiated transfer.
68  * The rnw, data and data_len fields must be initialized before calling any
69  * hci->cmd->*() method. The cmd method will initialize cmd_desc[] and
70  * possibly modify (clear) the data field. Then xfer->cmd_desc[0] can
71  * be augmented with CMD_0_ROC and/or CMD_0_TOC.
72  * The completion field needs to be initialized before queueing with
73  * hci->io->queue_xfer(), and requires CMD_0_ROC to be set.
74  */
75 struct hci_xfer {
76 	u32 cmd_desc[4];
77 	u32 response;
78 	bool rnw;
79 	void *data;
80 	unsigned int data_len;
81 	unsigned int cmd_tid;
82 	struct completion *completion;
83 	union {
84 		struct {
85 			/* PIO specific */
86 			struct hci_xfer *next_xfer;
87 			struct hci_xfer *next_data;
88 			struct hci_xfer *next_resp;
89 			unsigned int data_left;
90 			u32 data_word_before_partial;
91 		};
92 		struct {
93 			/* DMA specific */
94 			struct i3c_dma *dma;
95 			int ring_number;
96 			int ring_entry;
97 		};
98 	};
99 };
100 
101 static inline struct hci_xfer *hci_alloc_xfer(unsigned int n)
102 {
103 	return kcalloc(n, sizeof(struct hci_xfer), GFP_KERNEL);
104 }
105 
106 static inline void hci_free_xfer(struct hci_xfer *xfer, unsigned int n)
107 {
108 	kfree(xfer);
109 }
110 
111 
112 /* This abstracts PIO vs DMA operations */
113 struct hci_io_ops {
114 	bool (*irq_handler)(struct i3c_hci *hci);
115 	int (*queue_xfer)(struct i3c_hci *hci, struct hci_xfer *xfer, int n);
116 	bool (*dequeue_xfer)(struct i3c_hci *hci, struct hci_xfer *xfer, int n);
117 	int (*request_ibi)(struct i3c_hci *hci, struct i3c_dev_desc *dev,
118 			   const struct i3c_ibi_setup *req);
119 	void (*free_ibi)(struct i3c_hci *hci, struct i3c_dev_desc *dev);
120 	void (*recycle_ibi_slot)(struct i3c_hci *hci, struct i3c_dev_desc *dev,
121 				struct i3c_ibi_slot *slot);
122 	int (*init)(struct i3c_hci *hci);
123 	void (*cleanup)(struct i3c_hci *hci);
124 };
125 
126 extern const struct hci_io_ops mipi_i3c_hci_pio;
127 extern const struct hci_io_ops mipi_i3c_hci_dma;
128 
129 
130 /* Our per device master private data */
131 struct i3c_hci_dev_data {
132 	int dat_idx;
133 	void *ibi_data;
134 };
135 
136 
137 /* list of quirks */
138 #define HCI_QUIRK_RAW_CCC	BIT(1)	/* CCC framing must be explicit */
139 #define HCI_QUIRK_PIO_MODE	BIT(2)  /* Set PIO mode for AMD platforms */
140 #define HCI_QUIRK_OD_PP_TIMING		BIT(3)  /* Set OD and PP timings for AMD platforms */
141 #define HCI_QUIRK_RESP_BUF_THLD		BIT(4)  /* Set resp buf thld to 0 for AMD platforms */
142 
143 
144 /* global functions */
145 void mipi_i3c_hci_resume(struct i3c_hci *hci);
146 void mipi_i3c_hci_pio_reset(struct i3c_hci *hci);
147 void mipi_i3c_hci_dct_index_reset(struct i3c_hci *hci);
148 void amd_set_od_pp_timing(struct i3c_hci *hci);
149 void amd_set_resp_buf_thld(struct i3c_hci *hci);
150 
151 #endif
152