xref: /openbmc/u-boot/drivers/fpga/stratixv.c (revision b24a8ec1)
1 /*
2  * Copyright (C) 2016 Stefan Roese <sr@denx.de>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <altera.h>
9 #include <spi.h>
10 #include <asm/io.h>
11 #include <linux/errno.h>
12 
13 /* Write the RBF data to FPGA via SPI */
14 static int program_write(int spi_bus, int spi_dev, const void *rbf_data,
15 			 unsigned long rbf_size)
16 {
17 	struct spi_slave *slave;
18 	int ret;
19 
20 	debug("%s (%d): data=%p size=%ld\n",
21 	      __func__, __LINE__, rbf_data, rbf_size);
22 
23 	/* FIXME: How to get the max. SPI clock and SPI mode? */
24 	slave = spi_setup_slave(spi_bus, spi_dev, 27777777, SPI_MODE_3);
25 	if (!slave)
26 		return -1;
27 
28 	if (spi_claim_bus(slave))
29 		return -1;
30 
31 	ret = spi_xfer(slave, rbf_size * 8, rbf_data, (void *)rbf_data,
32 		       SPI_XFER_BEGIN | SPI_XFER_END);
33 
34 	spi_release_bus(slave);
35 
36 	return ret;
37 }
38 
39 /*
40  * This is the interface used by FPGA driver.
41  * Return 0 for sucess, non-zero for error.
42  */
43 int stratixv_load(Altera_desc *desc, const void *rbf_data, size_t rbf_size)
44 {
45 	altera_board_specific_func *pfns = desc->iface_fns;
46 	int cookie = desc->cookie;
47 	int spi_bus;
48 	int spi_dev;
49 	int ret = 0;
50 
51 	if ((u32)rbf_data & 0x3) {
52 		puts("FPGA: Unaligned data, realign to 32bit boundary.\n");
53 		return -EINVAL;
54 	}
55 
56 	/* Run the pre configuration function if there is one */
57 	if (pfns->pre)
58 		(pfns->pre)(cookie);
59 
60 	/* Establish the initial state */
61 	if (pfns->config) {
62 		/* De-assert nCONFIG */
63 		(pfns->config)(false, true, cookie);
64 
65 		/* nConfig minimum low pulse width is 2us */
66 		udelay(200);
67 
68 		/* Assert nCONFIG */
69 		(pfns->config)(true, true, cookie);
70 
71 		/* nCONFIG high to first rising clock on DCLK min 1506 us */
72 		udelay(1600);
73 	}
74 
75 	/* Write the RBF data to FPGA */
76 	if (pfns->write) {
77 		/*
78 		 * Use board specific data function to write bitstream
79 		 * into the FPGA
80 		 */
81 		ret = (pfns->write)(rbf_data, rbf_size, true, cookie);
82 	} else {
83 		/*
84 		 * Use common SPI functions to write bitstream into the
85 		 * FPGA
86 		 */
87 		spi_bus = COOKIE2SPI_BUS(cookie);
88 		spi_dev = COOKIE2SPI_DEV(cookie);
89 		ret = program_write(spi_bus, spi_dev, rbf_data, rbf_size);
90 	}
91 	if (ret)
92 		return ret;
93 
94 	/* Check done pin */
95 	if (pfns->done) {
96 		ret = (pfns->done)(cookie);
97 
98 		if (ret)
99 			printf("Error: DONE not set (ret=%d)!\n", ret);
100 	}
101 
102 	return ret;
103 }
104