1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
From 6cc4b54570d508413982d86bf68f60ccdb8687f8 Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Fri, 30 Apr 2021 11:24:24 +0100
Subject: [PATCH 01/14] arm64: smccc: Add support for SMCCCv1.2 extended
input/output registers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
SMCCC v1.2 allows x8-x17 to be used as parameter registers and x4—x17
to be used as result registers in SMC64/HVC64. Arm Firmware Framework
for Armv8-A specification makes use of x0-x7 as parameter and result
registers. There are other users like Hyper-V who intend to use beyond
x0-x7 as well.
Current SMCCC interface in the kernel just use x0-x7 as parameter and
x0-x3 as result registers as required by SMCCCv1.0. Let us add new
interface to support this extended set of input/output registers namely
x0-x17 as both parameter and result registers.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Upstream-Status: Backport [https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git/commit/?h=v5.10/ffa&id=d3d7f68912d370e80f7c293e04c8fecf76d704c5]
---
arch/arm64/kernel/asm-offsets.c | 9 ++++++
arch/arm64/kernel/smccc-call.S | 57 +++++++++++++++++++++++++++++++++
include/linux/arm-smccc.h | 55 +++++++++++++++++++++++++++++++
3 files changed, 121 insertions(+)
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index f396d951ee54..6545c497064e 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -138,6 +138,15 @@ int main(void)
DEFINE(ARM_SMCCC_RES_X2_OFFS, offsetof(struct arm_smccc_res, a2));
DEFINE(ARM_SMCCC_QUIRK_ID_OFFS, offsetof(struct arm_smccc_quirk, id));
DEFINE(ARM_SMCCC_QUIRK_STATE_OFFS, offsetof(struct arm_smccc_quirk, state));
+ DEFINE(ARM_SMCCC_1_2_REGS_X0_OFFS, offsetof(struct arm_smccc_1_2_regs, a0));
+ DEFINE(ARM_SMCCC_1_2_REGS_X2_OFFS, offsetof(struct arm_smccc_1_2_regs, a2));
+ DEFINE(ARM_SMCCC_1_2_REGS_X4_OFFS, offsetof(struct arm_smccc_1_2_regs, a4));
+ DEFINE(ARM_SMCCC_1_2_REGS_X6_OFFS, offsetof(struct arm_smccc_1_2_regs, a6));
+ DEFINE(ARM_SMCCC_1_2_REGS_X8_OFFS, offsetof(struct arm_smccc_1_2_regs, a8));
+ DEFINE(ARM_SMCCC_1_2_REGS_X10_OFFS, offsetof(struct arm_smccc_1_2_regs, a10));
+ DEFINE(ARM_SMCCC_1_2_REGS_X12_OFFS, offsetof(struct arm_smccc_1_2_regs, a12));
+ DEFINE(ARM_SMCCC_1_2_REGS_X14_OFFS, offsetof(struct arm_smccc_1_2_regs, a14));
+ DEFINE(ARM_SMCCC_1_2_REGS_X16_OFFS, offsetof(struct arm_smccc_1_2_regs, a16));
BLANK();
DEFINE(HIBERN_PBE_ORIG, offsetof(struct pbe, orig_address));
DEFINE(HIBERN_PBE_ADDR, offsetof(struct pbe, address));
diff --git a/arch/arm64/kernel/smccc-call.S b/arch/arm64/kernel/smccc-call.S
index d62447964ed9..2def9d0dd3dd 100644
--- a/arch/arm64/kernel/smccc-call.S
+++ b/arch/arm64/kernel/smccc-call.S
@@ -43,3 +43,60 @@ SYM_FUNC_START(__arm_smccc_hvc)
SMCCC hvc
SYM_FUNC_END(__arm_smccc_hvc)
EXPORT_SYMBOL(__arm_smccc_hvc)
+
+ .macro SMCCC_1_2 instr
+ /* Save `res` and free a GPR that won't be clobbered */
+ stp x1, x19, [sp, #-16]!
+
+ /* Ensure `args` won't be clobbered while loading regs in next step */
+ mov x19, x0
+
+ /* Load the registers x0 - x17 from the struct arm_smccc_1_2_regs */
+ ldp x0, x1, [x19, #ARM_SMCCC_1_2_REGS_X0_OFFS]
+ ldp x2, x3, [x19, #ARM_SMCCC_1_2_REGS_X2_OFFS]
+ ldp x4, x5, [x19, #ARM_SMCCC_1_2_REGS_X4_OFFS]
+ ldp x6, x7, [x19, #ARM_SMCCC_1_2_REGS_X6_OFFS]
+ ldp x8, x9, [x19, #ARM_SMCCC_1_2_REGS_X8_OFFS]
+ ldp x10, x11, [x19, #ARM_SMCCC_1_2_REGS_X10_OFFS]
+ ldp x12, x13, [x19, #ARM_SMCCC_1_2_REGS_X12_OFFS]
+ ldp x14, x15, [x19, #ARM_SMCCC_1_2_REGS_X14_OFFS]
+ ldp x16, x17, [x19, #ARM_SMCCC_1_2_REGS_X16_OFFS]
+
+ \instr #0
+
+ /* Load the `res` from the stack */
+ ldr x19, [sp]
+
+ /* Store the registers x0 - x17 into the result structure */
+ stp x0, x1, [x19, #ARM_SMCCC_1_2_REGS_X0_OFFS]
+ stp x2, x3, [x19, #ARM_SMCCC_1_2_REGS_X2_OFFS]
+ stp x4, x5, [x19, #ARM_SMCCC_1_2_REGS_X4_OFFS]
+ stp x6, x7, [x19, #ARM_SMCCC_1_2_REGS_X6_OFFS]
+ stp x8, x9, [x19, #ARM_SMCCC_1_2_REGS_X8_OFFS]
+ stp x10, x11, [x19, #ARM_SMCCC_1_2_REGS_X10_OFFS]
+ stp x12, x13, [x19, #ARM_SMCCC_1_2_REGS_X12_OFFS]
+ stp x14, x15, [x19, #ARM_SMCCC_1_2_REGS_X14_OFFS]
+ stp x16, x17, [x19, #ARM_SMCCC_1_2_REGS_X16_OFFS]
+
+ /* Restore original x19 */
+ ldp xzr, x19, [sp], #16
+ ret
+.endm
+
+/*
+ * void arm_smccc_1_2_hvc(const struct arm_smccc_1_2_regs *args,
+ * struct arm_smccc_1_2_regs *res);
+ */
+SYM_FUNC_START(arm_smccc_1_2_hvc)
+ SMCCC_1_2 hvc
+SYM_FUNC_END(arm_smccc_1_2_hvc)
+EXPORT_SYMBOL(arm_smccc_1_2_hvc)
+
+/*
+ * void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args,
+ * struct arm_smccc_1_2_regs *res);
+ */
+SYM_FUNC_START(arm_smccc_1_2_smc)
+ SMCCC_1_2 smc
+SYM_FUNC_END(arm_smccc_1_2_smc)
+EXPORT_SYMBOL(arm_smccc_1_2_smc)
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 62c54234576c..c8eb24af3c62 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -186,6 +186,61 @@ struct arm_smccc_res {
unsigned long a3;
};
+#ifdef CONFIG_ARM64
+/**
+ * struct arm_smccc_1_2_regs - Arguments for or Results from SMC/HVC call
+ * @a0-a17 argument values from registers 0 to 17
+ */
+struct arm_smccc_1_2_regs {
+ unsigned long a0;
+ unsigned long a1;
+ unsigned long a2;
+ unsigned long a3;
+ unsigned long a4;
+ unsigned long a5;
+ unsigned long a6;
+ unsigned long a7;
+ unsigned long a8;
+ unsigned long a9;
+ unsigned long a10;
+ unsigned long a11;
+ unsigned long a12;
+ unsigned long a13;
+ unsigned long a14;
+ unsigned long a15;
+ unsigned long a16;
+ unsigned long a17;
+};
+
+/**
+ * arm_smccc_1_2_hvc() - make HVC calls
+ * @args: arguments passed via struct arm_smccc_1_2_regs
+ * @res: result values via struct arm_smccc_1_2_regs
+ *
+ * This function is used to make HVC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied from the
+ * structure to registers prior to the HVC instruction. The return values
+ * are updated with the content from registers on return from the HVC
+ * instruction.
+ */
+asmlinkage void arm_smccc_1_2_hvc(const struct arm_smccc_1_2_regs *args,
+ struct arm_smccc_1_2_regs *res);
+
+/**
+ * arm_smccc_1_2_smc() - make SMC calls
+ * @args: arguments passed via struct arm_smccc_1_2_regs
+ * @res: result values via struct arm_smccc_1_2_regs
+ *
+ * This function is used to make SMC calls following SMC Calling Convention
+ * v1.2 or above. The content of the supplied param are copied from the
+ * structure to registers prior to the SMC instruction. The return values
+ * are updated with the content from registers on return from the SMC
+ * instruction.
+ */
+asmlinkage void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args,
+ struct arm_smccc_1_2_regs *res);
+#endif
+
/**
* struct arm_smccc_quirk - Contains quirk information
* @id: quirk identification
--
2.29.2
|
