xref: /openbmc/linux/drivers/spi/spi-dw.h (revision 93f5715e)
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 
36 /* Bit fields in CTRLR0 */
37 #define SPI_DFS_OFFSET			0
38 
39 #define SPI_FRF_OFFSET			4
40 #define SPI_FRF_SPI			0x0
41 #define SPI_FRF_SSP			0x1
42 #define SPI_FRF_MICROWIRE		0x2
43 #define SPI_FRF_RESV			0x3
44 
45 #define SPI_MODE_OFFSET			6
46 #define SPI_SCPH_OFFSET			6
47 #define SPI_SCOL_OFFSET			7
48 
49 #define SPI_TMOD_OFFSET			8
50 #define SPI_TMOD_MASK			(0x3 << SPI_TMOD_OFFSET)
51 #define	SPI_TMOD_TR			0x0		/* xmit & recv */
52 #define SPI_TMOD_TO			0x1		/* xmit only */
53 #define SPI_TMOD_RO			0x2		/* recv only */
54 #define SPI_TMOD_EPROMREAD		0x3		/* eeprom read mode */
55 
56 #define SPI_SLVOE_OFFSET		10
57 #define SPI_SRL_OFFSET			11
58 #define SPI_CFS_OFFSET			12
59 
60 /* Bit fields in SR, 7 bits */
61 #define SR_MASK				0x7f		/* cover 7 bits */
62 #define SR_BUSY				(1 << 0)
63 #define SR_TF_NOT_FULL			(1 << 1)
64 #define SR_TF_EMPT			(1 << 2)
65 #define SR_RF_NOT_EMPT			(1 << 3)
66 #define SR_RF_FULL			(1 << 4)
67 #define SR_TX_ERR			(1 << 5)
68 #define SR_DCOL				(1 << 6)
69 
70 /* Bit fields in ISR, IMR, RISR, 7 bits */
71 #define SPI_INT_TXEI			(1 << 0)
72 #define SPI_INT_TXOI			(1 << 1)
73 #define SPI_INT_RXUI			(1 << 2)
74 #define SPI_INT_RXOI			(1 << 3)
75 #define SPI_INT_RXFI			(1 << 4)
76 #define SPI_INT_MSTI			(1 << 5)
77 
78 /* Bit fields in DMACR */
79 #define SPI_DMA_RDMAE			(1 << 0)
80 #define SPI_DMA_TDMAE			(1 << 1)
81 
82 /* TX RX interrupt level threshold, max can be 256 */
83 #define SPI_INT_THRESHOLD		32
84 
85 enum dw_ssi_type {
86 	SSI_MOTO_SPI = 0,
87 	SSI_TI_SSP,
88 	SSI_NS_MICROWIRE,
89 };
90 
91 struct dw_spi;
92 struct dw_spi_dma_ops {
93 	int (*dma_init)(struct dw_spi *dws);
94 	void (*dma_exit)(struct dw_spi *dws);
95 	int (*dma_setup)(struct dw_spi *dws, struct spi_transfer *xfer);
96 	bool (*can_dma)(struct spi_controller *master, struct spi_device *spi,
97 			struct spi_transfer *xfer);
98 	int (*dma_transfer)(struct dw_spi *dws, struct spi_transfer *xfer);
99 	void (*dma_stop)(struct dw_spi *dws);
100 };
101 
102 struct dw_spi {
103 	struct spi_controller	*master;
104 	enum dw_ssi_type	type;
105 
106 	void __iomem		*regs;
107 	unsigned long		paddr;
108 	int			irq;
109 	u32			fifo_len;	/* depth of the FIFO buffer */
110 	u32			max_freq;	/* max bus freq supported */
111 
112 	u32			reg_io_width;	/* DR I/O width in bytes */
113 	u16			bus_num;
114 	u16			num_cs;		/* supported slave numbers */
115 	void (*set_cs)(struct spi_device *spi, bool enable);
116 
117 	/* Current message transfer state info */
118 	size_t			len;
119 	void			*tx;
120 	void			*tx_end;
121 	void			*rx;
122 	void			*rx_end;
123 	int			dma_mapped;
124 	u8			n_bytes;	/* current is a 1/2 bytes op */
125 	u32			dma_width;
126 	irqreturn_t		(*transfer_handler)(struct dw_spi *dws);
127 	u32			current_freq;	/* frequency in hz */
128 
129 	/* DMA info */
130 	int			dma_inited;
131 	struct dma_chan		*txchan;
132 	struct dma_chan		*rxchan;
133 	unsigned long		dma_chan_busy;
134 	dma_addr_t		dma_addr; /* phy address of the Data register */
135 	const struct dw_spi_dma_ops *dma_ops;
136 	void			*dma_tx;
137 	void			*dma_rx;
138 
139 	/* Bus interface info */
140 	void			*priv;
141 #ifdef CONFIG_DEBUG_FS
142 	struct dentry *debugfs;
143 #endif
144 };
145 
146 static inline u32 dw_readl(struct dw_spi *dws, u32 offset)
147 {
148 	return __raw_readl(dws->regs + offset);
149 }
150 
151 static inline u16 dw_readw(struct dw_spi *dws, u32 offset)
152 {
153 	return __raw_readw(dws->regs + offset);
154 }
155 
156 static inline void dw_writel(struct dw_spi *dws, u32 offset, u32 val)
157 {
158 	__raw_writel(val, dws->regs + offset);
159 }
160 
161 static inline void dw_writew(struct dw_spi *dws, u32 offset, u16 val)
162 {
163 	__raw_writew(val, dws->regs + offset);
164 }
165 
166 static inline u32 dw_read_io_reg(struct dw_spi *dws, u32 offset)
167 {
168 	switch (dws->reg_io_width) {
169 	case 2:
170 		return dw_readw(dws, offset);
171 	case 4:
172 	default:
173 		return dw_readl(dws, offset);
174 	}
175 }
176 
177 static inline void dw_write_io_reg(struct dw_spi *dws, u32 offset, u32 val)
178 {
179 	switch (dws->reg_io_width) {
180 	case 2:
181 		dw_writew(dws, offset, val);
182 		break;
183 	case 4:
184 	default:
185 		dw_writel(dws, offset, val);
186 		break;
187 	}
188 }
189 
190 static inline void spi_enable_chip(struct dw_spi *dws, int enable)
191 {
192 	dw_writel(dws, DW_SPI_SSIENR, (enable ? 1 : 0));
193 }
194 
195 static inline void spi_set_clk(struct dw_spi *dws, u16 div)
196 {
197 	dw_writel(dws, DW_SPI_BAUDR, div);
198 }
199 
200 /* Disable IRQ bits */
201 static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)
202 {
203 	u32 new_mask;
204 
205 	new_mask = dw_readl(dws, DW_SPI_IMR) & ~mask;
206 	dw_writel(dws, DW_SPI_IMR, new_mask);
207 }
208 
209 /* Enable IRQ bits */
210 static inline void spi_umask_intr(struct dw_spi *dws, u32 mask)
211 {
212 	u32 new_mask;
213 
214 	new_mask = dw_readl(dws, DW_SPI_IMR) | mask;
215 	dw_writel(dws, DW_SPI_IMR, new_mask);
216 }
217 
218 /*
219  * This does disable the SPI controller, interrupts, and re-enable the
220  * controller back. Transmit and receive FIFO buffers are cleared when the
221  * device is disabled.
222  */
223 static inline void spi_reset_chip(struct dw_spi *dws)
224 {
225 	spi_enable_chip(dws, 0);
226 	spi_mask_intr(dws, 0xff);
227 	spi_enable_chip(dws, 1);
228 }
229 
230 static inline void spi_shutdown_chip(struct dw_spi *dws)
231 {
232 	spi_enable_chip(dws, 0);
233 	spi_set_clk(dws, 0);
234 }
235 
236 /*
237  * Each SPI slave device to work with dw_api controller should
238  * has such a structure claiming its working mode (poll or PIO/DMA),
239  * which can be save in the "controller_data" member of the
240  * struct spi_device.
241  */
242 struct dw_spi_chip {
243 	u8 poll_mode;	/* 1 for controller polling mode */
244 	u8 type;	/* SPI/SSP/MicroWire */
245 	void (*cs_control)(u32 command);
246 };
247 
248 extern void dw_spi_set_cs(struct spi_device *spi, bool enable);
249 extern int dw_spi_add_host(struct device *dev, struct dw_spi *dws);
250 extern void dw_spi_remove_host(struct dw_spi *dws);
251 extern int dw_spi_suspend_host(struct dw_spi *dws);
252 extern int dw_spi_resume_host(struct dw_spi *dws);
253 
254 /* platform related setup */
255 extern int dw_spi_mid_init(struct dw_spi *dws); /* Intel MID platforms */
256 #endif /* DW_SPI_HEADER_H */
257