1 /*
2  *
3  * (C) COPYRIGHT 2015 ARM Limited. All rights reserved.
4  *
5  * This program is free software and is provided to you under the terms of the
6  * GNU General Public License version 2 as published by the Free Software
7  * Foundation, and any use by you of this program is subject to the terms
8  * of such GNU licence.
9  *
10  * A copy of the licence is included with the program, and can also be obtained
11  * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
12  * Boston, MA  02110-1301, USA.
13  *
14  */
15 
16 
17 
18 #ifdef CONFIG_ARM64
19 
20 #include <mali_kbase.h>
21 #include <mali_kbase_smc.h>
22 
23 #include <linux/compiler.h>
24 
25 /* __asmeq is not available on Kernel versions >= 4.20 */
26 #ifndef __asmeq
27 /*
28  * This is used to ensure the compiler did actually allocate the register we
29  * asked it for some inline assembly sequences.  Apparently we can't trust the
30  * compiler from one version to another so a bit of paranoia won't hurt.  This
31  * string is meant to be concatenated with the inline asm string and will
32  * cause compilation to stop on mismatch.  (for details, see gcc PR 15089)
33  */
34 #define __asmeq(x, y)  ".ifnc " x "," y " ; .err ; .endif\n\t"
35 #endif
36 
invoke_smc_fid(u64 function_id, u64 arg0, u64 arg1, u64 arg2)37 static noinline u64 invoke_smc_fid(u64 function_id,
38 		u64 arg0, u64 arg1, u64 arg2)
39 {
40 	register u64 x0 asm("x0") = function_id;
41 	register u64 x1 asm("x1") = arg0;
42 	register u64 x2 asm("x2") = arg1;
43 	register u64 x3 asm("x3") = arg2;
44 
45 	asm volatile(
46 			__asmeq("%0", "x0")
47 			__asmeq("%1", "x1")
48 			__asmeq("%2", "x2")
49 			__asmeq("%3", "x3")
50 			"smc    #0\n"
51 			: "+r" (x0)
52 			: "r" (x1), "r" (x2), "r" (x3));
53 
54 	return x0;
55 }
56 
kbase_invoke_smc_fid(u32 fid, u64 arg0, u64 arg1, u64 arg2)57 u64 kbase_invoke_smc_fid(u32 fid, u64 arg0, u64 arg1, u64 arg2)
58 {
59 	/* Is fast call (bit 31 set) */
60 	KBASE_DEBUG_ASSERT(fid & ~SMC_FAST_CALL);
61 	/* bits 16-23 must be zero for fast calls */
62 	KBASE_DEBUG_ASSERT((fid & (0xFF << 16)) == 0);
63 
64 	return invoke_smc_fid(fid, arg0, arg1, arg2);
65 }
66 
kbase_invoke_smc(u32 oen, u16 function_number, bool smc64, u64 arg0, u64 arg1, u64 arg2)67 u64 kbase_invoke_smc(u32 oen, u16 function_number, bool smc64,
68 		u64 arg0, u64 arg1, u64 arg2)
69 {
70 	u32 fid = 0;
71 
72 	/* Only the six bits allowed should be used. */
73 	KBASE_DEBUG_ASSERT((oen & ~SMC_OEN_MASK) == 0);
74 
75 	fid |= SMC_FAST_CALL; /* Bit 31: Fast call */
76 	if (smc64)
77 		fid |= SMC_64; /* Bit 30: 1=SMC64, 0=SMC32 */
78 	fid |= oen; /* Bit 29:24: OEN */
79 	/* Bit 23:16: Must be zero for fast calls */
80 	fid |= (function_number); /* Bit 15:0: function number */
81 
82 	return kbase_invoke_smc_fid(fid, arg0, arg1, arg2);
83 }
84 
85 #endif /* CONFIG_ARM64 */
86 
87