summaryrefslogtreecommitdiff
path: root/drivers/spi/kirkwood_spi.c
blob: ce2ba96008fbc8a60213f3278e238e4da2eab5ac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
/*
 * (C) Copyright 2009
 * Marvell Semiconductor <www.marvell.com>
 * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
 *
 * Derived from drivers/spi/mpc8xxx_spi.c
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <malloc.h>
#include <spi.h>
#include <asm/io.h>
#include <asm/arch/soc.h>
#ifdef CONFIG_KIRKWOOD
#include <asm/arch/mpp.h>
#endif
#include <asm/arch-mvebu/spi.h>

static struct kwspi_registers *spireg = (struct kwspi_registers *)KW_SPI_BASE;

#ifdef CONFIG_KIRKWOOD
static u32 cs_spi_mpp_back[2];
#endif

struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
				unsigned int max_hz, unsigned int mode)
{
	struct spi_slave *slave;
	u32 data;
#ifdef CONFIG_KIRKWOOD
	static const u32 kwspi_mpp_config[2][2] = {
		{ MPP0_SPI_SCn, 0 }, /* if cs == 0 */
		{ MPP7_SPI_SCn, 0 } /* if cs != 0 */
	};
#endif

	if (!spi_cs_is_valid(bus, cs))
		return NULL;

	slave = spi_alloc_slave_base(bus, cs);
	if (!slave)
		return NULL;

	writel(KWSPI_SMEMRDY, &spireg->ctrl);

	/* calculate spi clock prescaller using max_hz */
	data = ((CONFIG_SYS_TCLK / 2) / max_hz) + 0x10;
	data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data;
	data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data;

	/* program spi clock prescaller using max_hz */
	writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg);
	debug("data = 0x%08x\n", data);

	writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
	writel(KWSPI_IRQMASK, &spireg->irq_mask);

#ifdef CONFIG_KIRKWOOD
	/* program mpp registers to select  SPI_CSn */
	kirkwood_mpp_conf(kwspi_mpp_config[cs ? 1 : 0], cs_spi_mpp_back);
#endif

	return slave;
}

void spi_free_slave(struct spi_slave *slave)
{
#ifdef CONFIG_KIRKWOOD
	kirkwood_mpp_conf(cs_spi_mpp_back, NULL);
#endif
	free(slave);
}

#if defined(CONFIG_SYS_KW_SPI_MPP)
u32 spi_mpp_backup[4];
#endif

__attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave)
{
	return 0;
}

int spi_claim_bus(struct spi_slave *slave)
{
#if defined(CONFIG_SYS_KW_SPI_MPP)
	u32 config;
	u32 spi_mpp_config[4];

	config = CONFIG_SYS_KW_SPI_MPP;

	if (config & MOSI_MPP6)
		spi_mpp_config[0] = MPP6_SPI_MOSI;
	else
		spi_mpp_config[0] = MPP1_SPI_MOSI;

	if (config & SCK_MPP10)
		spi_mpp_config[1] = MPP10_SPI_SCK;
	else
		spi_mpp_config[1] = MPP2_SPI_SCK;

	if (config & MISO_MPP11)
		spi_mpp_config[2] = MPP11_SPI_MISO;
	else
		spi_mpp_config[2] = MPP3_SPI_MISO;

	spi_mpp_config[3] = 0;
	spi_mpp_backup[3] = 0;

	/* set new spi mpp and save current mpp config */
	kirkwood_mpp_conf(spi_mpp_config, spi_mpp_backup);
#endif

	return board_spi_claim_bus(slave);
}

__attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave)
{
}

void spi_release_bus(struct spi_slave *slave)
{
#if defined(CONFIG_SYS_KW_SPI_MPP)
	kirkwood_mpp_conf(spi_mpp_backup, NULL);
#endif

	board_spi_release_bus(slave);
}

#ifndef CONFIG_SPI_CS_IS_VALID
/*
 * you can define this function board specific
 * define above CONFIG in board specific config file and
 * provide the function in board specific src file
 */
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
	return bus == 0 && (cs == 0 || cs == 1);
}
#endif

void spi_init(void)
{
}

void spi_cs_activate(struct spi_slave *slave)
{
	setbits_le32(&spireg->ctrl, KWSPI_CSN_ACT);
}

void spi_cs_deactivate(struct spi_slave *slave)
{
	clrbits_le32(&spireg->ctrl, KWSPI_CSN_ACT);
}

int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
	     void *din, unsigned long flags)
{
	unsigned int tmpdout, tmpdin;
	int tm, isread = 0;

	debug("spi_xfer: slave %u:%u dout %p din %p bitlen %u\n",
	      slave->bus, slave->cs, dout, din, bitlen);

	if (flags & SPI_XFER_BEGIN)
		spi_cs_activate(slave);

	/*
	 * handle data in 8-bit chunks
	 * TBD: 2byte xfer mode to be enabled
	 */
	clrsetbits_le32(&spireg->cfg, KWSPI_XFERLEN_MASK, KWSPI_XFERLEN_1BYTE);

	while (bitlen > 4) {
		debug("loopstart bitlen %d\n", bitlen);
		tmpdout = 0;

		/* Shift data so it's msb-justified */
		if (dout)
			tmpdout = *(u32 *)dout & 0xff;

		clrbits_le32(&spireg->irq_cause, KWSPI_SMEMRDIRQ);
		writel(tmpdout, &spireg->dout);	/* Write the data out */
		debug("*** spi_xfer: ... %08x written, bitlen %d\n",
		      tmpdout, bitlen);

		/*
		 * Wait for SPI transmit to get out
		 * or time out (1 second = 1000 ms)
		 * The NE event must be read and cleared first
		 */
		for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
			if (readl(&spireg->irq_cause) & KWSPI_SMEMRDIRQ) {
				isread = 1;
				tmpdin = readl(&spireg->din);
				debug("spi_xfer: din %p..%08x read\n",
				      din, tmpdin);

				if (din) {
					*((u8 *)din) = (u8)tmpdin;
					din += 1;
				}
				if (dout)
					dout += 1;
				bitlen -= 8;
			}
			if (isread)
				break;
		}
		if (tm >= KWSPI_TIMEOUT)
			printf("*** spi_xfer: Time out during SPI transfer\n");

		debug("loopend bitlen %d\n", bitlen);
	}

	if (flags & SPI_XFER_END)
		spi_cs_deactivate(slave);

	return 0;
}