1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * ePAPR para-virtualization support. |
4 | * |
5 | * Copyright (C) 2012 Freescale Semiconductor, Inc. |
6 | */ |
7 | |
8 | #include <linux/of.h> |
9 | #include <linux/of_fdt.h> |
10 | #include <asm/epapr_hcalls.h> |
11 | #include <asm/cacheflush.h> |
12 | #include <asm/code-patching.h> |
13 | #include <asm/machdep.h> |
14 | #include <asm/inst.h> |
15 | |
16 | #if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) |
17 | extern void epapr_ev_idle(void); |
18 | extern u32 epapr_ev_idle_start[]; |
19 | #endif |
20 | |
21 | bool epapr_paravirt_enabled; |
22 | static bool __maybe_unused epapr_has_idle; |
23 | |
24 | static int __init early_init_dt_scan_epapr(unsigned long node, |
25 | const char *uname, |
26 | int depth, void *data) |
27 | { |
28 | const u32 *insts; |
29 | int len; |
30 | int i; |
31 | |
32 | insts = of_get_flat_dt_prop(node, name: "hcall-instructions" , size: &len); |
33 | if (!insts) |
34 | return 0; |
35 | |
36 | if (len % 4 || len > (4 * 4)) |
37 | return -1; |
38 | |
39 | for (i = 0; i < (len / 4); i++) { |
40 | ppc_inst_t inst = ppc_inst(be32_to_cpu(insts[i])); |
41 | patch_instruction(epapr_hypercall_start + i, inst); |
42 | #if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) |
43 | patch_instruction(epapr_ev_idle_start + i, inst); |
44 | #endif |
45 | } |
46 | |
47 | #if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) |
48 | if (of_get_flat_dt_prop(node, "has-idle" , NULL)) |
49 | epapr_has_idle = true; |
50 | #endif |
51 | |
52 | epapr_paravirt_enabled = true; |
53 | |
54 | return 1; |
55 | } |
56 | |
57 | int __init epapr_paravirt_early_init(void) |
58 | { |
59 | of_scan_flat_dt(it: early_init_dt_scan_epapr, NULL); |
60 | |
61 | return 0; |
62 | } |
63 | |
64 | static int __init epapr_idle_init(void) |
65 | { |
66 | #if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) |
67 | if (epapr_has_idle) |
68 | ppc_md.power_save = epapr_ev_idle; |
69 | #endif |
70 | |
71 | return 0; |
72 | } |
73 | |
74 | postcore_initcall(epapr_idle_init); |
75 | |