xref: /openbmc/linux/drivers/spi/spi-dw.h (revision ed1666f6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef DW_SPI_HEADER_H
3 #define DW_SPI_HEADER_H
4 
5 #include <linux/io.h>
6 #include <linux/scatterlist.h>
7 #include <linux/gpio.h>
8 
9 /* Register offsets */
10 #define DW_SPI_CTRL0			0x00
11 #define DW_SPI_CTRL1			0x04
12 #define DW_SPI_SSIENR			0x08
13 #define DW_SPI_MWCR			0x0c
14 #define DW_SPI_SER			0x10
15 #define DW_SPI_BAUDR			0x14
16 #define DW_SPI_TXFLTR			0x18
17 #define DW_SPI_RXFLTR			0x1c
18 #define DW_SPI_TXFLR			0x20
19 #define DW_SPI_RXFLR			0x24
20 #define DW_SPI_SR			0x28
21 #define DW_SPI_IMR			0x2c
22 #define DW_SPI_ISR			0x30
23 #define DW_SPI_RISR			0x34
24 #define DW_SPI_TXOICR			0x38
25 #define DW_SPI_RXOICR			0x3c
26 #define DW_SPI_RXUICR			0x40
27 #define DW_SPI_MSTICR			0x44
28 #define DW_SPI_ICR			0x48
29 #define DW_SPI_DMACR			0x4c
30 #define DW_SPI_DMATDLR			0x50
31 #define DW_SPI_DMARDLR			0x54
32 #define DW_SPI_IDR			0x58
33 #define DW_SPI_VERSION			0x5c
34 #define DW_SPI_DR			0x60
35 #define DW_SPI_CS_OVERRIDE		0xf4
36 
37 /* Bit fields in CTRLR0 */
38 #define SPI_DFS_OFFSET			0
39 
40 #define SPI_FRF_OFFSET			4
41 #define SPI_FRF_SPI			0x0
42 #define SPI_FRF_SSP			0x1
43 #define SPI_FRF_MICROWIRE		0x2
44 #define SPI_FRF_RESV			0x3
45 
46 #define SPI_MODE_OFFSET			6
47 #define SPI_SCPH_OFFSET			6
48 #define SPI_SCOL_OFFSET			7
49 
50 #define SPI_TMOD_OFFSET			8
51 #define SPI_TMOD_MASK			(0x3 << SPI_TMOD_OFFSET)
52 #define	SPI_TMOD_TR			0x0		/* xmit & recv */
53 #define SPI_TMOD_TO			0x1		/* xmit only */
54 #define SPI_TMOD_RO			0x2		/* recv only */
55 #define SPI_TMOD_EPROMREAD		0x3		/* eeprom read mode */
56 
57 #define SPI_SLVOE_OFFSET		10
58 #define SPI_SRL_OFFSET			11
59 #define SPI_CFS_OFFSET			12
60 
61 /* Bit fields in SR, 7 bits */
62 #define SR_MASK				0x7f		/* cover 7 bits */
63 #define SR_BUSY				(1 << 0)
64 #define SR_TF_NOT_FULL			(1 << 1)
65 #define SR_TF_EMPT			(1 << 2)
66 #define SR_RF_NOT_EMPT			(1 << 3)
67 #define SR_RF_FULL			(1 << 4)
68 #define SR_TX_ERR			(1 << 5)
69 #define SR_DCOL				(1 << 6)
70 
71 /* Bit fields in ISR, IMR, RISR, 7 bits */
72 #define SPI_INT_TXEI			(1 << 0)
73 #define SPI_INT_TXOI			(1 << 1)
74 #define SPI_INT_RXUI			(1 << 2)
75 #define SPI_INT_RXOI			(1 << 3)
76 #define SPI_INT_RXFI			(1 << 4)
77 #define SPI_INT_MSTI			(1 << 5)
78 
79 /* Bit fields in DMACR */
80 #define SPI_DMA_RDMAE			(1 << 0)
81 #define SPI_DMA_TDMAE			(1 << 1)
82 
83 /* TX RX interrupt level threshold, max can be 256 */
84 #define SPI_INT_THRESHOLD		32
85 
86 enum dw_ssi_type {
87 	SSI_MOTO_SPI = 0,
88 	SSI_TI_SSP,
89 	SSI_NS_MICROWIRE,
90 };
91 
92 struct dw_spi;
93 struct dw_spi_dma_ops {
94 	int (*dma_init)(struct dw_spi *dws);
95 	void (*dma_exit)(struct dw_spi *dws);
96 	int (*dma_setup)(struct dw_spi *dws, struct spi_transfer *xfer);
97 	bool (*can_dma)(struct spi_controller *master, struct spi_device *spi,
98 			struct spi_transfer *xfer);
99 	int (*dma_transfer)(struct dw_spi *dws, struct spi_transfer *xfer);
100 	void (*dma_stop)(struct dw_spi *dws);
101 };
102 
103 struct dw_spi {
104 	struct spi_controller	*master;
105 	enum dw_ssi_type	type;
106 
107 	void __iomem		*regs;
108 	unsigned long		paddr;
109 	int			irq;
110 	u32			fifo_len;	/* depth of the FIFO buffer */
111 	u32			max_freq;	/* max bus freq supported */
112 
113 	int			cs_override;
114 	u32			reg_io_width;	/* DR I/O width in bytes */
115 	u16			bus_num;
116 	u16			num_cs;		/* supported slave numbers */
117 	void (*set_cs)(struct spi_device *spi, bool enable);
118 
119 	/* Current message transfer state info */
120 	size_t			len;
121 	void			*tx;
122 	void			*tx_end;
123 	void			*rx;
124 	void			*rx_end;
125 	int			dma_mapped;
126 	u8			n_bytes;	/* current is a 1/2 bytes op */
127 	u32			dma_width;
128 	irqreturn_t		(*transfer_handler)(struct dw_spi *dws);
129 	u32			current_freq;	/* frequency in hz */
130 
131 	/* DMA info */
132 	int			dma_inited;
133 	struct dma_chan		*txchan;
134 	struct dma_chan		*rxchan;
135 	unsigned long		dma_chan_busy;
136 	dma_addr_t		dma_addr; /* phy address of the Data register */
137 	const struct dw_spi_dma_ops *dma_ops;
138 	void			*dma_tx;
139 	void			*dma_rx;
140 
141 	/* Bus interface info */
142 	void			*priv;
143 #ifdef CONFIG_DEBUG_FS
144 	struct dentry *debugfs;
145 #endif
146 };
147 
148 static inline u32 dw_readl(struct dw_spi *dws, u32 offset)
149 {
150 	return __raw_readl(dws->regs + offset);
151 }
152 
153 static inline u16 dw_readw(struct dw_spi *dws, u32 offset)
154 {
155 	return __raw_readw(dws->regs + offset);
156 }
157 
158 static inline void dw_writel(struct dw_spi *dws, u32 offset, u32 val)
159 {
160 	__raw_writel(val, dws->regs + offset);
161 }
162 
163 static inline void dw_writew(struct dw_spi *dws, u32 offset, u16 val)
164 {
165 	__raw_writew(val, dws->regs + offset);
166 }
167 
168 static inline u32 dw_read_io_reg(struct dw_spi *dws, u32 offset)
169 {
170 	switch (dws->reg_io_width) {
171 	case 2:
172 		return dw_readw(dws, offset);
173 	case 4:
174 	default:
175 		return dw_readl(dws, offset);
176 	}
177 }
178 
179 static inline void dw_write_io_reg(struct dw_spi *dws, u32 offset, u32 val)
180 {
181 	switch (dws->reg_io_width) {
182 	case 2:
183 		dw_writew(dws, offset, val);
184 		break;
185 	case 4:
186 	default:
187 		dw_writel(dws, offset, val);
188 		break;
189 	}
190 }
191 
192 static inline void spi_enable_chip(struct dw_spi *dws, int enable)
193 {
194 	dw_writel(dws, DW_SPI_SSIENR, (enable ? 1 : 0));
195 }
196 
197 static inline void spi_set_clk(struct dw_spi *dws, u16 div)
198 {
199 	dw_writel(dws, DW_SPI_BAUDR, div);
200 }
201 
202 /* Disable IRQ bits */
203 static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)
204 {
205 	u32 new_mask;
206 
207 	new_mask = dw_readl(dws, DW_SPI_IMR) & ~mask;
208 	dw_writel(dws, DW_SPI_IMR, new_mask);
209 }
210 
211 /* Enable IRQ bits */
212 static inline void spi_umask_intr(struct dw_spi *dws, u32 mask)
213 {
214 	u32 new_mask;
215 
216 	new_mask = dw_readl(dws, DW_SPI_IMR) | mask;
217 	dw_writel(dws, DW_SPI_IMR, new_mask);
218 }
219 
220 /*
221  * This does disable the SPI controller, interrupts, and re-enable the
222  * controller back. Transmit and receive FIFO buffers are cleared when the
223  * device is disabled.
224  */
225 static inline void spi_reset_chip(struct dw_spi *dws)
226 {
227 	spi_enable_chip(dws, 0);
228 	spi_mask_intr(dws, 0xff);
229 	spi_enable_chip(dws, 1);
230 }
231 
232 static inline void spi_shutdown_chip(struct dw_spi *dws)
233 {
234 	spi_enable_chip(dws, 0);
235 	spi_set_clk(dws, 0);
236 }
237 
238 /*
239  * Each SPI slave device to work with dw_api controller should
240  * has such a structure claiming its working mode (poll or PIO/DMA),
241  * which can be save in the "controller_data" member of the
242  * struct spi_device.
243  */
244 struct dw_spi_chip {
245 	u8 poll_mode;	/* 1 for controller polling mode */
246 	u8 type;	/* SPI/SSP/MicroWire */
247 	void (*cs_control)(u32 command);
248 };
249 
250 extern void dw_spi_set_cs(struct spi_device *spi, bool enable);
251 extern int dw_spi_add_host(struct device *dev, struct dw_spi *dws);
252 extern void dw_spi_remove_host(struct dw_spi *dws);
253 extern int dw_spi_suspend_host(struct dw_spi *dws);
254 extern int dw_spi_resume_host(struct dw_spi *dws);
255 
256 /* platform related setup */
257 extern int dw_spi_mid_init(struct dw_spi *dws); /* Intel MID platforms */
258 #endif /* DW_SPI_HEADER_H */
259