1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Gemini 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 #include <asm/system_misc.h>
12 #include <asm/proc-fns.h>
13
14 #ifdef CONFIG_DEBUG_GEMINI
15 /* This is needed for LL-debug/earlyprintk/debug-macro.S */
16 static struct map_desc gemini_io_desc[] __initdata = {
17 {
18 .virtual = CONFIG_DEBUG_UART_VIRT,
19 .pfn = __phys_to_pfn(CONFIG_DEBUG_UART_PHYS),
20 .length = SZ_4K,
21 .type = MT_DEVICE,
22 },
23 };
24
gemini_map_io(void)25 static void __init gemini_map_io(void)
26 {
27 iotable_init(gemini_io_desc, ARRAY_SIZE(gemini_io_desc));
28 }
29 #else
30 #define gemini_map_io NULL
31 #endif
32
gemini_idle(void)33 static void gemini_idle(void)
34 {
35 /*
36 * Because of broken hardware we have to enable interrupts or the CPU
37 * will never wakeup... Acctualy it is not very good to enable
38 * interrupts first since scheduler can miss a tick, but there is
39 * no other way around this. Platforms that needs it for power saving
40 * should enable it in init code, since by default it is
41 * disabled.
42 */
43
44 /* FIXME: Enabling interrupts here is racy! */
45 raw_local_irq_enable();
46 cpu_do_idle();
47 raw_local_irq_disable();
48 }
49
gemini_init_machine(void)50 static void __init gemini_init_machine(void)
51 {
52 arm_pm_idle = gemini_idle;
53 }
54
55 static const char *gemini_board_compat[] = {
56 "cortina,gemini",
57 NULL,
58 };
59
60 DT_MACHINE_START(GEMINI_DT, "Gemini (Device Tree)")
61 .map_io = gemini_map_io,
62 .init_machine = gemini_init_machine,
63 .dt_compat = gemini_board_compat,
64 MACHINE_END
65