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/mod_devicetable.h>
17 #include <linux/of.h>
18 #include <linux/spi/spi.h>
19
xilinx_spi_write(struct xilinx_fpga_core * core,const char * buf,size_t count)20 static int xilinx_spi_write(struct xilinx_fpga_core *core, const char *buf,
21 size_t count)
22 {
23 struct spi_device *spi = to_spi_device(core->dev);
24 const char *fw_data = buf;
25 const char *fw_data_end = fw_data + count;
26
27 while (fw_data < fw_data_end) {
28 size_t remaining, stride;
29 int ret;
30
31 remaining = fw_data_end - fw_data;
32 stride = min_t(size_t, remaining, SZ_4K);
33
34 ret = spi_write(spi, fw_data, stride);
35 if (ret) {
36 dev_err(core->dev, "SPI error in firmware write: %d\n",
37 ret);
38 return ret;
39 }
40 fw_data += stride;
41 }
42
43 return 0;
44 }
45
xilinx_spi_probe(struct spi_device * spi)46 static int xilinx_spi_probe(struct spi_device *spi)
47 {
48 struct xilinx_fpga_core *core;
49
50 core = devm_kzalloc(&spi->dev, sizeof(*core), GFP_KERNEL);
51 if (!core)
52 return -ENOMEM;
53
54 core->dev = &spi->dev;
55 core->write = xilinx_spi_write;
56
57 return xilinx_core_probe(core);
58 }
59
60 static const struct spi_device_id xilinx_spi_ids[] = {
61 { "fpga-slave-serial" },
62 { },
63 };
64 MODULE_DEVICE_TABLE(spi, xilinx_spi_ids);
65
66 #ifdef CONFIG_OF
67 static const struct of_device_id xlnx_spi_of_match[] = {
68 {
69 .compatible = "xlnx,fpga-slave-serial",
70 },
71 {}
72 };
73 MODULE_DEVICE_TABLE(of, xlnx_spi_of_match);
74 #endif
75
76 static struct spi_driver xilinx_slave_spi_driver = {
77 .driver = {
78 .name = "xlnx-slave-spi",
79 .of_match_table = of_match_ptr(xlnx_spi_of_match),
80 },
81 .probe = xilinx_spi_probe,
82 .id_table = xilinx_spi_ids,
83 };
84
85 module_spi_driver(xilinx_slave_spi_driver)
86
87 MODULE_LICENSE("GPL v2");
88 MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
89 MODULE_DESCRIPTION("Load Xilinx FPGA firmware over SPI");
90