1 /*
2 * SDK7786 FPGA Support.
3 *
4 * Copyright (C) 2010 Paul Mundt
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10 #include <linux/init.h>
11 #include <linux/io.h>
12 #include <linux/bcd.h>
13 #include <mach/fpga.h>
14 #include <asm/sizes.h>
15
16 #define FPGA_REGS_OFFSET 0x03fff800
17 #define FPGA_REGS_SIZE 0x490
18
19 /*
20 * The FPGA can be mapped in any of the generally available areas,
21 * so we attempt to scan for it using the fixed SRSTR read magic.
22 *
23 * Once the FPGA is located, the rest of the mapping data for the other
24 * components can be determined dynamically from its section mapping
25 * registers.
26 */
sdk7786_fpga_probe(void)27 static void __iomem *sdk7786_fpga_probe(void)
28 {
29 unsigned long area;
30 void __iomem *base;
31
32 /*
33 * Iterate over all of the areas where the FPGA could be mapped.
34 * The possible range is anywhere from area 0 through 6, area 7
35 * is reserved.
36 */
37 for (area = PA_AREA0; area < PA_AREA7; area += SZ_64M) {
38 base = ioremap_nocache(area + FPGA_REGS_OFFSET, FPGA_REGS_SIZE);
39 if (!base) {
40 /* Failed to remap this area, move along. */
41 continue;
42 }
43
44 if (ioread16(base + SRSTR) == SRSTR_MAGIC)
45 return base; /* Found it! */
46
47 iounmap(base);
48 }
49
50 return NULL;
51 }
52
53 void __iomem *sdk7786_fpga_base;
54
sdk7786_fpga_init(void)55 void __init sdk7786_fpga_init(void)
56 {
57 u16 version, date;
58
59 sdk7786_fpga_base = sdk7786_fpga_probe();
60 if (unlikely(!sdk7786_fpga_base)) {
61 panic("FPGA detection failed.\n");
62 return;
63 }
64
65 version = fpga_read_reg(FPGAVR);
66 date = fpga_read_reg(FPGADR);
67
68 pr_info("\tFPGA version:\t%d.%d (built on %d/%d/%d)\n",
69 bcd2bin(version >> 8) & 0xf, bcd2bin(version & 0xf),
70 ((date >> 12) & 0xf) + 2000,
71 (date >> 8) & 0xf, bcd2bin(date & 0xff));
72 }
73