arm64: rsi: Add RSI definitions

The RMM (Realm Management Monitor) provides functionality that can be
accessed by a realm guest through SMC (Realm Services Interface) calls.

The SMC definitions are based on DEN0137[1] version 1.0-rel0.

[1] https://developer.arm.com/documentation/den0137/1-0rel0/

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20241017131434.40935-2-steven.price@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/rsi_cmds.h b/arch/arm64/include/asm/rsi_cmds.h
new file mode 100644 (file)
index 0000000..2fcf351
--- /dev/null
+++ b/arch/arm64/include/asm/rsi_cmds.h
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2023 ARM Ltd.
+ */
+
+#ifndef __ASM_RSI_CMDS_H
+#define __ASM_RSI_CMDS_H
+
+#include <linux/arm-smccc.h>
+
+#include <asm/rsi_smc.h>
+
+#define RSI_GRANULE_SHIFT              12
+#define RSI_GRANULE_SIZE               (_AC(1, UL) << RSI_GRANULE_SHIFT)
+
+enum ripas {
+       RSI_RIPAS_EMPTY = 0,
+       RSI_RIPAS_RAM = 1,
+       RSI_RIPAS_DESTROYED = 2,
+       RSI_RIPAS_DEV = 3,
+};
+
+static inline unsigned long rsi_request_version(unsigned long req,
+                                               unsigned long *out_lower,
+                                               unsigned long *out_higher)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_smc(SMC_RSI_ABI_VERSION, req, 0, 0, 0, 0, 0, 0, &res);
+
+       if (out_lower)
+               *out_lower = res.a1;
+       if (out_higher)
+               *out_higher = res.a2;
+
+       return res.a0;
+}
+
+static inline unsigned long rsi_get_realm_config(struct realm_config *cfg)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_smc(SMC_RSI_REALM_CONFIG, virt_to_phys(cfg),
+                     0, 0, 0, 0, 0, 0, &res);
+       return res.a0;
+}
+
+static inline long rsi_set_addr_range_state(phys_addr_t start,
+                                           phys_addr_t end,
+                                           enum ripas state,
+                                           unsigned long flags,
+                                           phys_addr_t *top)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_smc(SMC_RSI_IPA_STATE_SET, start, end, state,
+                     flags, 0, 0, 0, &res);
+
+       if (top)
+               *top = res.a1;
+
+       if (res.a2 != RSI_ACCEPT)
+               return -EPERM;
+
+       return res.a0;
+}
+
+/**
+ * rsi_attestation_token_init - Initialise the operation to retrieve an
+ * attestation token.
+ *
+ * @challenge: The challenge data to be used in the attestation token
+ *             generation.
+ * @size:      Size of the challenge data in bytes.
+ *
+ * Initialises the attestation token generation and returns an upper bound
+ * on the attestation token size that can be used to allocate an adequate
+ * buffer. The caller is expected to subsequently call
+ * rsi_attestation_token_continue() to retrieve the attestation token data on
+ * the same CPU.
+ *
+ * Returns:
+ *  On success, returns the upper limit of the attestation report size.
+ *  Otherwise, -EINVAL
+ */
+static inline long
+rsi_attestation_token_init(const u8 *challenge, unsigned long size)
+{
+       struct arm_smccc_1_2_regs regs = { 0 };
+
+       /* The challenge must be at least 32bytes and at most 64bytes */
+       if (!challenge || size < 32 || size > 64)
+               return -EINVAL;
+
+       regs.a0 = SMC_RSI_ATTESTATION_TOKEN_INIT;
+       memcpy(&regs.a1, challenge, size);
+       arm_smccc_1_2_smc(&regs, &regs);
+
+       if (regs.a0 == RSI_SUCCESS)
+               return regs.a1;
+
+       return -EINVAL;
+}
+
+/**
+ * rsi_attestation_token_continue - Continue the operation to retrieve an
+ * attestation token.
+ *
+ * @granule: {I}PA of the Granule to which the token will be written.
+ * @offset:  Offset within Granule to start of buffer in bytes.
+ * @size:    The size of the buffer.
+ * @len:     The number of bytes written to the buffer.
+ *
+ * Retrieves up to a RSI_GRANULE_SIZE worth of token data per call. The caller
+ * is expected to call rsi_attestation_token_init() before calling this
+ * function to retrieve the attestation token.
+ *
+ * Return:
+ * * %RSI_SUCCESS     - Attestation token retrieved successfully.
+ * * %RSI_INCOMPLETE  - Token generation is not complete.
+ * * %RSI_ERROR_INPUT - A parameter was not valid.
+ * * %RSI_ERROR_STATE - Attestation not in progress.
+ */
+static inline unsigned long rsi_attestation_token_continue(phys_addr_t granule,
+                                                          unsigned long offset,
+                                                          unsigned long size,
+                                                          unsigned long *len)
+{
+       struct arm_smccc_res res;
+
+       arm_smccc_1_1_invoke(SMC_RSI_ATTESTATION_TOKEN_CONTINUE,
+                            granule, offset, size, 0, &res);
+
+       if (len)
+               *len = res.a1;
+       return res.a0;
+}
+
+#endif /* __ASM_RSI_CMDS_H */

diff --git a/arch/arm64/include/asm/rsi_smc.h b/arch/arm64/include/asm/rsi_smc.h
new file mode 100644 (file)
index 0000000..6cb070e
--- /dev/null
+++ b/arch/arm64/include/asm/rsi_smc.h
@@ -0,0 +1,193 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2023 ARM Ltd.
+ */
+
+#ifndef __ASM_RSI_SMC_H_
+#define __ASM_RSI_SMC_H_
+
+#include <linux/arm-smccc.h>
+
+/*
+ * This file describes the Realm Services Interface (RSI) Application Binary
+ * Interface (ABI) for SMC calls made from within the Realm to the RMM and
+ * serviced by the RMM.
+ */
+
+/*
+ * The major version number of the RSI implementation.  This is increased when
+ * the binary format or semantics of the SMC calls change.
+ */
+#define RSI_ABI_VERSION_MAJOR          UL(1)
+
+/*
+ * The minor version number of the RSI implementation.  This is increased when
+ * a bug is fixed, or a feature is added without breaking binary compatibility.
+ */
+#define RSI_ABI_VERSION_MINOR          UL(0)
+
+#define RSI_ABI_VERSION                        ((RSI_ABI_VERSION_MAJOR << 16) | \
+                                        RSI_ABI_VERSION_MINOR)
+
+#define RSI_ABI_VERSION_GET_MAJOR(_version) ((_version) >> 16)
+#define RSI_ABI_VERSION_GET_MINOR(_version) ((_version) & 0xFFFF)
+
+#define RSI_SUCCESS            UL(0)
+#define RSI_ERROR_INPUT                UL(1)
+#define RSI_ERROR_STATE                UL(2)
+#define RSI_INCOMPLETE         UL(3)
+#define RSI_ERROR_UNKNOWN      UL(4)
+
+#define SMC_RSI_FID(n)         ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,      \
+                                                  ARM_SMCCC_SMC_64,         \
+                                                  ARM_SMCCC_OWNER_STANDARD, \
+                                                  n)
+
+/*
+ * Returns RSI version.
+ *
+ * arg1 == Requested interface revision
+ * ret0 == Status / error
+ * ret1 == Lower implemented interface revision
+ * ret2 == Higher implemented interface revision
+ */
+#define SMC_RSI_ABI_VERSION    SMC_RSI_FID(0x190)
+
+/*
+ * Read feature register.
+ *
+ * arg1 == Feature register index
+ * ret0 == Status / error
+ * ret1 == Feature register value
+ */
+#define SMC_RSI_FEATURES                       SMC_RSI_FID(0x191)
+
+/*
+ * Read measurement for the current Realm.
+ *
+ * arg1 == Index, which measurements slot to read
+ * ret0 == Status / error
+ * ret1 == Measurement value, bytes:  0 -  7
+ * ret2 == Measurement value, bytes:  8 - 15
+ * ret3 == Measurement value, bytes: 16 - 23
+ * ret4 == Measurement value, bytes: 24 - 31
+ * ret5 == Measurement value, bytes: 32 - 39
+ * ret6 == Measurement value, bytes: 40 - 47
+ * ret7 == Measurement value, bytes: 48 - 55
+ * ret8 == Measurement value, bytes: 56 - 63
+ */
+#define SMC_RSI_MEASUREMENT_READ               SMC_RSI_FID(0x192)
+
+/*
+ * Extend Realm Extensible Measurement (REM) value.
+ *
+ * arg1  == Index, which measurements slot to extend
+ * arg2  == Size of realm measurement in bytes, max 64 bytes
+ * arg3  == Measurement value, bytes:  0 -  7
+ * arg4  == Measurement value, bytes:  8 - 15
+ * arg5  == Measurement value, bytes: 16 - 23
+ * arg6  == Measurement value, bytes: 24 - 31
+ * arg7  == Measurement value, bytes: 32 - 39
+ * arg8  == Measurement value, bytes: 40 - 47
+ * arg9  == Measurement value, bytes: 48 - 55
+ * arg10 == Measurement value, bytes: 56 - 63
+ * ret0  == Status / error
+ */
+#define SMC_RSI_MEASUREMENT_EXTEND             SMC_RSI_FID(0x193)
+
+/*
+ * Initialize the operation to retrieve an attestation token.
+ *
+ * arg1 == Challenge value, bytes:  0 -  7
+ * arg2 == Challenge value, bytes:  8 - 15
+ * arg3 == Challenge value, bytes: 16 - 23
+ * arg4 == Challenge value, bytes: 24 - 31
+ * arg5 == Challenge value, bytes: 32 - 39
+ * arg6 == Challenge value, bytes: 40 - 47
+ * arg7 == Challenge value, bytes: 48 - 55
+ * arg8 == Challenge value, bytes: 56 - 63
+ * ret0 == Status / error
+ * ret1 == Upper bound of token size in bytes
+ */
+#define SMC_RSI_ATTESTATION_TOKEN_INIT         SMC_RSI_FID(0x194)
+
+/*
+ * Continue the operation to retrieve an attestation token.
+ *
+ * arg1 == The IPA of token buffer
+ * arg2 == Offset within the granule of the token buffer
+ * arg3 == Size of the granule buffer
+ * ret0 == Status / error
+ * ret1 == Length of token bytes copied to the granule buffer
+ */
+#define SMC_RSI_ATTESTATION_TOKEN_CONTINUE     SMC_RSI_FID(0x195)
+
+#ifndef __ASSEMBLY__
+
+struct realm_config {
+       union {
+               struct {
+                       unsigned long ipa_bits; /* Width of IPA in bits */
+                       unsigned long hash_algo; /* Hash algorithm */
+               };
+               u8 pad[0x200];
+       };
+       union {
+               u8 rpv[64]; /* Realm Personalization Value */
+               u8 pad2[0xe00];
+       };
+       /*
+        * The RMM requires the configuration structure to be aligned to a 4k
+        * boundary, ensure this happens by aligning this structure.
+        */
+} __aligned(0x1000);
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * Read configuration for the current Realm.
+ *
+ * arg1 == struct realm_config addr
+ * ret0 == Status / error
+ */
+#define SMC_RSI_REALM_CONFIG                   SMC_RSI_FID(0x196)
+
+/*
+ * Request RIPAS of a target IPA range to be changed to a specified value.
+ *
+ * arg1 == Base IPA address of target region
+ * arg2 == Top of the region
+ * arg3 == RIPAS value
+ * arg4 == flags
+ * ret0 == Status / error
+ * ret1 == Top of modified IPA range
+ * ret2 == Whether the Host accepted or rejected the request
+ */
+#define SMC_RSI_IPA_STATE_SET                  SMC_RSI_FID(0x197)
+
+#define RSI_NO_CHANGE_DESTROYED                        UL(0)
+#define RSI_CHANGE_DESTROYED                   UL(1)
+
+#define RSI_ACCEPT                             UL(0)
+#define RSI_REJECT                             UL(1)
+
+/*
+ * Get RIPAS of a target IPA range.
+ *
+ * arg1 == Base IPA of target region
+ * arg2 == End of target IPA region
+ * ret0 == Status / error
+ * ret1 == Top of IPA region which has the reported RIPAS value
+ * ret2 == RIPAS value
+ */
+#define SMC_RSI_IPA_STATE_GET                  SMC_RSI_FID(0x198)
+
+/*
+ * Make a Host call.
+ *
+ * arg1 == IPA of host call structure
+ * ret0 == Status / error
+ */
+#define SMC_RSI_HOST_CALL                      SMC_RSI_FID(0x199)
+
+#endif /* __ASM_RSI_SMC_H_ */