xref: /openbmc/u-boot/drivers/fpga/stratixv.c (revision dd1033e4)
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 <spi.h>
9 #include <asm/io.h>
10 #include <linux/errno.h>
11 
12 /* Write the RBF data to FPGA via SPI */
13 static int program_write(int spi_bus, int spi_dev, const void *rbf_data,
14 			 unsigned long rbf_size)
15 {
16 	struct spi_slave *slave;
17 	int ret;
18 
19 	debug("%s (%d): data=%p size=%ld\n",
20 	      __func__, __LINE__, rbf_data, rbf_size);
21 
22 	/* FIXME: How to get the max. SPI clock and SPI mode? */
23 	slave = spi_setup_slave(spi_bus, spi_dev, 27777777, SPI_MODE_3);
24 	if (!slave)
25 		return -1;
26 
27 	if (spi_claim_bus(slave))
28 		return -1;
29 
30 	ret = spi_xfer(slave, rbf_size * 8, rbf_data, (void *)rbf_data,
31 		       SPI_XFER_BEGIN | SPI_XFER_END);
32 
33 	spi_release_bus(slave);
34 
35 	return ret;
36 }
37 
38 /*
39  * This is the interface used by FPGA driver.
40  * Return 0 for sucess, non-zero for error.
41  */
42 int stratixv_load(Altera_desc *desc, const void *rbf_data, size_t rbf_size)
43 {
44 	altera_board_specific_func *pfns = desc->iface_fns;
45 	int cookie = desc->cookie;
46 	int spi_bus;
47 	int spi_dev;
48 	int ret = 0;
49 
50 	if ((u32)rbf_data & 0x3) {
51 		puts("FPGA: Unaligned data, realign to 32bit boundary.\n");
52 		return -EINVAL;
53 	}
54 
55 	/* Run the pre configuration function if there is one */
56 	if (pfns->pre)
57 		(pfns->pre)(cookie);
58 
59 	/* Establish the initial state */
60 	if (pfns->config) {
61 		/* De-assert nCONFIG */
62 		(pfns->config)(false, true, cookie);
63 
64 		/* nConfig minimum low pulse width is 2us */
65 		udelay(200);
66 
67 		/* Assert nCONFIG */
68 		(pfns->config)(true, true, cookie);
69 
70 		/* nCONFIG high to first rising clock on DCLK min 1506 us */
71 		udelay(1600);
72 	}
73 
74 	/* Write the RBF data to FPGA */
75 	if (pfns->write) {
76 		/*
77 		 * Use board specific data function to write bitstream
78 		 * into the FPGA
79 		 */
80 		ret = (pfns->write)(rbf_data, rbf_size, true, cookie);
81 	} else {
82 		/*
83 		 * Use common SPI functions to write bitstream into the
84 		 * FPGA
85 		 */
86 		spi_bus = COOKIE2SPI_BUS(cookie);
87 		spi_dev = COOKIE2SPI_DEV(cookie);
88 		ret = program_write(spi_bus, spi_dev, rbf_data, rbf_size);
89 	}
90 	if (ret)
91 		return ret;
92 
93 	/* Check done pin */
94 	if (pfns->done) {
95 		ret = (pfns->done)(cookie);
96 
97 		if (ret)
98 			printf("Error: DONE not set (ret=%d)!\n", ret);
99 	}
100 
101 	return ret;
102 }
103