1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Xilinx Spartan6 and 7 Series Slave Serial SPI Driver
4 *
5 * Copyright (C) 2017 DENX Software Engineering
6 *
7 * Anatolij Gustschin <agust@denx.de>
8 *
9 * Manage Xilinx FPGA firmware that is loaded over SPI using
10 * the slave serial configuration interface.
11 */
12
13 #include "xilinx-core.h"
14
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/spi/spi.h>
18
xilinx_spi_write(struct xilinx_fpga_core * core,const char * buf,size_t count)19 static int xilinx_spi_write(struct xilinx_fpga_core *core, const char *buf,
20 size_t count)
21 {
22 struct spi_device *spi = to_spi_device(core->dev);
23 const char *fw_data = buf;
24 const char *fw_data_end = fw_data + count;
25
26 while (fw_data < fw_data_end) {
27 size_t remaining, stride;
28 int ret;
29
30 remaining = fw_data_end - fw_data;
31 stride = min_t(size_t, remaining, SZ_4K);
32
33 ret = spi_write(spi, fw_data, stride);
34 if (ret) {
35 dev_err(core->dev, "SPI error in firmware write: %d\n",
36 ret);
37 return ret;
38 }
39 fw_data += stride;
40 }
41
42 return 0;
43 }
44
xilinx_spi_probe(struct spi_device * spi)45 static int xilinx_spi_probe(struct spi_device *spi)
46 {
47 struct xilinx_fpga_core *core;
48
49 core = devm_kzalloc(&spi->dev, sizeof(*core), GFP_KERNEL);
50 if (!core)
51 return -ENOMEM;
52
53 core->dev = &spi->dev;
54 core->write = xilinx_spi_write;
55
56 return xilinx_core_probe(core);
57 }
58
59 static const struct spi_device_id xilinx_spi_ids[] = {
60 { "fpga-slave-serial" },
61 { },
62 };
63 MODULE_DEVICE_TABLE(spi, xilinx_spi_ids);
64
65 #ifdef CONFIG_OF
66 static const struct of_device_id xlnx_spi_of_match[] = {
67 {
68 .compatible = "xlnx,fpga-slave-serial",
69 },
70 {}
71 };
72 MODULE_DEVICE_TABLE(of, xlnx_spi_of_match);
73 #endif
74
75 static struct spi_driver xilinx_slave_spi_driver = {
76 .driver = {
77 .name = "xlnx-slave-spi",
78 .of_match_table = of_match_ptr(xlnx_spi_of_match),
79 },
80 .probe = xilinx_spi_probe,
81 .id_table = xilinx_spi_ids,
82 };
83
84 module_spi_driver(xilinx_slave_spi_driver)
85
86 MODULE_LICENSE("GPL v2");
87 MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
88 MODULE_DESCRIPTION("Load Xilinx FPGA firmware over SPI");
89