xref: /openbmc/u-boot/board/theadorable/fpga.c (revision cbd2fba1)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Stefan Roese <sr@denx.de>
4  */
5 
6 #include <common.h>
7 #include <altera.h>
8 #include <errno.h>
9 #include <asm/gpio.h>
10 #include <asm/io.h>
11 #include <asm/arch/cpu.h>
12 #include <asm/arch/soc.h>
13 #include <asm/arch-mvebu/spi.h>
14 #include "theadorable.h"
15 
16 /*
17  * FPGA programming support
18  */
19 static int fpga_pre_fn(int cookie)
20 {
21 	int gpio_config = COOKIE2CONFIG(cookie);
22 	int gpio_done = COOKIE2DONE(cookie);
23 	int ret;
24 
25 	debug("%s (%d): cookie=%08x gpio_config=%d gpio_done=%d\n",
26 	      __func__, __LINE__, cookie, gpio_config, gpio_done);
27 
28 	/* Configure config pin */
29 	/* Set to output */
30 	ret = gpio_request(gpio_config, "CONFIG");
31 	if (ret < 0)
32 		return ret;
33 	gpio_direction_output(gpio_config, 1);
34 
35 	/* Configure done pin */
36 	/* Set to input */
37 	ret = gpio_request(gpio_done, "DONE");
38 	if (ret < 0)
39 		return ret;
40 
41 	gpio_direction_input(gpio_done);
42 
43 	return 0;
44 }
45 
46 static int fpga_config_fn(int assert, int flush, int cookie)
47 {
48 	int gpio_config = COOKIE2CONFIG(cookie);
49 
50 	debug("%s (%d): cookie=%08x gpio_config=%d\n",
51 	      __func__, __LINE__, cookie, gpio_config);
52 
53 	if (assert)
54 		gpio_set_value(gpio_config, 1);
55 	else
56 		gpio_set_value(gpio_config, 0);
57 
58 	return 0;
59 }
60 
61 static int fpga_write_fn(const void *buf, size_t len, int flush, int cookie)
62 {
63 	int spi_bus = COOKIE2SPI_BUS(cookie);
64 	int spi_dev = COOKIE2SPI_DEV(cookie);
65 	struct kwspi_registers *reg;
66 	u32 control_reg;
67 	u32 config_reg;
68 	void *dst;
69 
70 	/*
71 	 * Write data to FPGA attached to SPI bus via SPI direct write.
72 	 * This results in the fastest and easiest way to program the
73 	 * bitstream into the FPGA.
74 	 */
75 	debug("%s (%d): cookie=%08x spi_bus=%d spi_dev=%d\n",
76 	      __func__, __LINE__, cookie, spi_bus, spi_dev);
77 
78 	if (spi_bus == 0) {
79 		reg = (struct kwspi_registers *)MVEBU_REGISTER(0x10600);
80 		dst = (void *)SPI_BUS0_DEV1_BASE;
81 	} else {
82 		reg = (struct kwspi_registers *)MVEBU_REGISTER(0x10680);
83 		dst = (void *)SPI_BUS1_DEV2_BASE;
84 	}
85 
86 	/* Configure SPI controller for direct access mode */
87 	control_reg = readl(&reg->ctrl);
88 	config_reg = readl(&reg->cfg);
89 	writel(0x00000214, &reg->cfg);		/* 27MHz clock */
90 	writel(0x00000000, &reg->dw_cfg);	/* don't de-asset CS */
91 	writel(KWSPI_CSN_ACT, &reg->ctrl);	/* activate CS */
92 
93 	/* Copy data to the SPI direct mapped window */
94 	memcpy(dst, buf, len);
95 
96 	/* Restore original register values */
97 	writel(control_reg, &reg->ctrl);
98 	writel(config_reg, &reg->cfg);
99 
100 	return 0;
101 }
102 
103 /* Returns the state of CONF_DONE Pin */
104 static int fpga_done_fn(int cookie)
105 {
106 	int gpio_done = COOKIE2DONE(cookie);
107 	unsigned long ts;
108 
109 	debug("%s (%d): cookie=%08x gpio_done=%d\n",
110 	      __func__, __LINE__, cookie, gpio_done);
111 
112 	ts = get_timer(0);
113 	do {
114 		if (gpio_get_value(gpio_done))
115 			return 0;
116 	} while (get_timer(ts) < 1000);
117 
118 	/* timeout so return error */
119 	return -ENODEV;
120 }
121 
122 static altera_board_specific_func stratixv_fns = {
123 	.pre = fpga_pre_fn,
124 	.config = fpga_config_fn,
125 	.write = fpga_write_fn,
126 	.done = fpga_done_fn,
127 };
128 
129 static Altera_desc altera_fpga[] = {
130 	{
131 		/* Family */
132 		Altera_StratixV,
133 		/* Interface type */
134 		passive_serial,
135 		/* No limitation as additional data will be ignored */
136 		-1,
137 		/* Device function table */
138 		(void *)&stratixv_fns,
139 		/* Base interface address specified in driver */
140 		NULL,
141 		/* Cookie implementation */
142 		/*
143 		 * In this 32bit word the following information is coded:
144 		 * Bit 31 ... Bit 0
145 		 * SPI-Bus | SPI-Dev | Config-Pin | Done-Pin
146 		 */
147 		FPGA_COOKIE(0, 1, 26, 7)
148 	},
149 	{
150 		/* Family */
151 		Altera_StratixV,
152 		/* Interface type */
153 		passive_serial,
154 		/* No limitation as additional data will be ignored */
155 		-1,
156 		/* Device function table */
157 		(void *)&stratixv_fns,
158 		/* Base interface address specified in driver */
159 		NULL,
160 		/* Cookie implementation */
161 		/*
162 		 * In this 32bit word the following information is coded:
163 		 * Bit 31 ... Bit 0
164 		 * SPI-Bus | SPI-Dev | Config-Pin | Done-Pin
165 		 */
166 		FPGA_COOKIE(1, 2, 29, 9)
167 	},
168 };
169 
170 /* Add device descriptor to FPGA device table */
171 void board_fpga_add(void)
172 {
173 	int i;
174 
175 	fpga_init();
176 	for (i = 0; i < ARRAY_SIZE(altera_fpga); i++)
177 		fpga_add(fpga_altera, &altera_fpga[i]);
178 }
179