1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * IXP4xx Device Tree boot support
4 */
5 #include <linux/kernel.h>
6 #include <linux/init.h>
7 #include <linux/io.h>
8
9 #include <asm/mach/arch.h>
10 #include <asm/mach/map.h>
11
12 /*
13 * These are the only fixed phys to virt mappings we ever need
14 * we put it right after the UART mapping at 0xffc80000-0xffc81fff
15 */
16 #define IXP4XX_EXP_CFG_BASE_PHYS 0xC4000000
17 #define IXP4XX_EXP_CFG_BASE_VIRT 0xFEC14000
18
19 static struct map_desc ixp4xx_of_io_desc[] __initdata = {
20 /*
21 * This is needed for runtime system configuration checks,
22 * such as reading if hardware so-and-so is present. This
23 * could eventually be converted into a syscon once all boards
24 * are converted to device tree.
25 */
26 {
27 .virtual = IXP4XX_EXP_CFG_BASE_VIRT,
28 .pfn = __phys_to_pfn(IXP4XX_EXP_CFG_BASE_PHYS),
29 .length = SZ_4K,
30 .type = MT_DEVICE,
31 },
32 #ifdef CONFIG_DEBUG_UART_8250
33 /* This is needed for LL-debug/earlyprintk/debug-macro.S */
34 {
35 .virtual = CONFIG_DEBUG_UART_VIRT,
36 .pfn = __phys_to_pfn(CONFIG_DEBUG_UART_PHYS),
37 .length = SZ_4K,
38 .type = MT_DEVICE,
39 },
40 #endif
41 };
42
ixp4xx_of_map_io(void)43 static void __init ixp4xx_of_map_io(void)
44 {
45 iotable_init(ixp4xx_of_io_desc, ARRAY_SIZE(ixp4xx_of_io_desc));
46 }
47
48 /*
49 * We handle 4 differen SoC families. These compatible strings are enough
50 * to provide the core so that different boards can add their more detailed
51 * specifics.
52 */
53 static const char *ixp4xx_of_board_compat[] = {
54 "intel,ixp42x",
55 "intel,ixp43x",
56 "intel,ixp45x",
57 "intel,ixp46x",
58 NULL,
59 };
60
61 DT_MACHINE_START(IXP4XX_DT, "IXP4xx (Device Tree)")
62 .map_io = ixp4xx_of_map_io,
63 .dt_compat = ixp4xx_of_board_compat,
64 MACHINE_END
65