1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * SDK7786 FPGA Support. |
4 | * |
5 | * Copyright (C) 2010 Paul Mundt |
6 | */ |
7 | #include <linux/init.h> |
8 | #include <linux/io.h> |
9 | #include <linux/bcd.h> |
10 | #include <mach/fpga.h> |
11 | #include <linux/sizes.h> |
12 | |
13 | #define FPGA_REGS_OFFSET 0x03fff800 |
14 | #define FPGA_REGS_SIZE 0x490 |
15 | |
16 | /* |
17 | * The FPGA can be mapped in any of the generally available areas, |
18 | * so we attempt to scan for it using the fixed SRSTR read magic. |
19 | * |
20 | * Once the FPGA is located, the rest of the mapping data for the other |
21 | * components can be determined dynamically from its section mapping |
22 | * registers. |
23 | */ |
24 | static void __iomem *sdk7786_fpga_probe(void) |
25 | { |
26 | unsigned long area; |
27 | void __iomem *base; |
28 | |
29 | /* |
30 | * Iterate over all of the areas where the FPGA could be mapped. |
31 | * The possible range is anywhere from area 0 through 6, area 7 |
32 | * is reserved. |
33 | */ |
34 | for (area = PA_AREA0; area < PA_AREA7; area += SZ_64M) { |
35 | base = ioremap(offset: area + FPGA_REGS_OFFSET, FPGA_REGS_SIZE); |
36 | if (!base) { |
37 | /* Failed to remap this area, move along. */ |
38 | continue; |
39 | } |
40 | |
41 | if (ioread16(base + SRSTR) == SRSTR_MAGIC) |
42 | return base; /* Found it! */ |
43 | |
44 | iounmap(addr: base); |
45 | } |
46 | |
47 | return NULL; |
48 | } |
49 | |
50 | void __iomem *sdk7786_fpga_base; |
51 | |
52 | void __init sdk7786_fpga_init(void) |
53 | { |
54 | u16 version, date; |
55 | |
56 | sdk7786_fpga_base = sdk7786_fpga_probe(); |
57 | if (unlikely(!sdk7786_fpga_base)) { |
58 | panic(fmt: "FPGA detection failed.\n" ); |
59 | return; |
60 | } |
61 | |
62 | version = fpga_read_reg(FPGAVR); |
63 | date = fpga_read_reg(FPGADR); |
64 | |
65 | pr_info("\tFPGA version:\t%d.%d (built on %d/%d/%d)\n" , |
66 | bcd2bin(version >> 8) & 0xf, bcd2bin(version & 0xf), |
67 | ((date >> 12) & 0xf) + 2000, |
68 | (date >> 8) & 0xf, bcd2bin(date & 0xff)); |
69 | } |
70 | |