| /* |
| * QEMU ARM CP Register access and descriptions |
| * |
| * Copyright (c) 2022 Linaro Ltd |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version 2 |
| * of the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, see |
| * <http://www.gnu.org/licenses/gpl-2.0.html> |
| */ |
| |
| #ifndef TARGET_ARM_CPREGS_H |
| #define TARGET_ARM_CPREGS_H |
| |
| /* |
| * ARMCPRegInfo type field bits: |
| */ |
| enum { |
| /* |
| * Register must be handled specially during translation. |
| * The method is one of the values below: |
| */ |
| ARM_CP_SPECIAL_MASK = 0x000f, |
| /* Special: no change to PE state: writes ignored, reads ignored. */ |
| ARM_CP_NOP = 0x0001, |
| /* Special: sysreg is WFI, for v5 and v6. */ |
| ARM_CP_WFI = 0x0002, |
| /* Special: sysreg is NZCV. */ |
| ARM_CP_NZCV = 0x0003, |
| /* Special: sysreg is CURRENTEL. */ |
| ARM_CP_CURRENTEL = 0x0004, |
| /* Special: sysreg is DC ZVA or similar. */ |
| ARM_CP_DC_ZVA = 0x0005, |
| ARM_CP_DC_GVA = 0x0006, |
| ARM_CP_DC_GZVA = 0x0007, |
| |
| /* Flag: reads produce resetvalue; writes ignored. */ |
| ARM_CP_CONST = 1 << 4, |
| /* Flag: For ARM_CP_STATE_AA32, sysreg is 64-bit. */ |
| ARM_CP_64BIT = 1 << 5, |
| /* |
| * Flag: TB should not be ended after a write to this register |
| * (the default is that the TB ends after cp writes). |
| */ |
| ARM_CP_SUPPRESS_TB_END = 1 << 6, |
| /* |
| * Flag: Permit a register definition to override a previous definition |
| * for the same (cp, is64, crn, crm, opc1, opc2) tuple: either the new |
| * or the old must have the ARM_CP_OVERRIDE bit set. |
| */ |
| ARM_CP_OVERRIDE = 1 << 7, |
| /* |
| * Flag: Register is an alias view of some underlying state which is also |
| * visible via another register, and that the other register is handling |
| * migration and reset; registers marked ARM_CP_ALIAS will not be migrated |
| * but may have their state set by syncing of register state from KVM. |
| */ |
| ARM_CP_ALIAS = 1 << 8, |
| /* |
| * Flag: Register does I/O and therefore its accesses need to be marked |
| * with gen_io_start() and also end the TB. In particular, registers which |
| * implement clocks or timers require this. |
| */ |
| ARM_CP_IO = 1 << 9, |
| /* |
| * Flag: Register has no underlying state and does not support raw access |
| * for state saving/loading; it will not be used for either migration or |
| * KVM state synchronization. Typically this is for "registers" which are |
| * actually used as instructions for cache maintenance and so on. |
| */ |
| ARM_CP_NO_RAW = 1 << 10, |
| /* |
| * Flag: The read or write hook might raise an exception; the generated |
| * code will synchronize the CPU state before calling the hook so that it |
| * is safe for the hook to call raise_exception(). |
| */ |
| ARM_CP_RAISES_EXC = 1 << 11, |
| /* |
| * Flag: Writes to the sysreg might change the exception level - typically |
| * on older ARM chips. For those cases we need to re-read the new el when |
| * recomputing the translation flags. |
| */ |
| ARM_CP_NEWEL = 1 << 12, |
| /* |
| * Flag: Access check for this sysreg is identical to accessing FPU state |
| * from an instruction: use translation fp_access_check(). |
| */ |
| ARM_CP_FPU = 1 << 13, |
| /* |
| * Flag: Access check for this sysreg is identical to accessing SVE state |
| * from an instruction: use translation sve_access_check(). |
| */ |
| ARM_CP_SVE = 1 << 14, |
| /* Flag: Do not expose in gdb sysreg xml. */ |
| ARM_CP_NO_GDB = 1 << 15, |
| /* |
| * Flags: If EL3 but not EL2... |
| * - UNDEF: discard the cpreg, |
| * - KEEP: retain the cpreg as is, |
| * - C_NZ: set const on the cpreg, but retain resetvalue, |
| * - else: set const on the cpreg, zero resetvalue, aka RES0. |
| * See rule RJFFP in section D1.1.3 of DDI0487H.a. |
| */ |
| ARM_CP_EL3_NO_EL2_UNDEF = 1 << 16, |
| ARM_CP_EL3_NO_EL2_KEEP = 1 << 17, |
| ARM_CP_EL3_NO_EL2_C_NZ = 1 << 18, |
| /* |
| * Flag: Access check for this sysreg is constrained by the |
| * ARM pseudocode function CheckSMEAccess(). |
| */ |
| ARM_CP_SME = 1 << 19, |
| }; |
| |
| /* |
| * Valid values for ARMCPRegInfo state field, indicating which of |
| * the AArch32 and AArch64 execution states this register is visible in. |
| * If the reginfo doesn't explicitly specify then it is AArch32 only. |
| * If the reginfo is declared to be visible in both states then a second |
| * reginfo is synthesised for the AArch32 view of the AArch64 register, |
| * such that the AArch32 view is the lower 32 bits of the AArch64 one. |
| * Note that we rely on the values of these enums as we iterate through |
| * the various states in some places. |
| */ |
| typedef enum { |
| ARM_CP_STATE_AA32 = 0, |
| ARM_CP_STATE_AA64 = 1, |
| ARM_CP_STATE_BOTH = 2, |
| } CPState; |
| |
| /* |
| * ARM CP register secure state flags. These flags identify security state |
| * attributes for a given CP register entry. |
| * The existence of both or neither secure and non-secure flags indicates that |
| * the register has both a secure and non-secure hash entry. A single one of |
| * these flags causes the register to only be hashed for the specified |
| * security state. |
| * Although definitions may have any combination of the S/NS bits, each |
| * registered entry will only have one to identify whether the entry is secure |
| * or non-secure. |
| */ |
| typedef enum { |
| ARM_CP_SECSTATE_BOTH = 0, /* define one cpreg for each secstate */ |
| ARM_CP_SECSTATE_S = (1 << 0), /* bit[0]: Secure state register */ |
| ARM_CP_SECSTATE_NS = (1 << 1), /* bit[1]: Non-secure state register */ |
| } CPSecureState; |
| |
| /* |
| * Access rights: |
| * We define bits for Read and Write access for what rev C of the v7-AR ARM ARM |
| * defines as PL0 (user), PL1 (fiq/irq/svc/abt/und/sys, ie privileged), and |
| * PL2 (hyp). The other level which has Read and Write bits is Secure PL1 |
| * (ie any of the privileged modes in Secure state, or Monitor mode). |
| * If a register is accessible in one privilege level it's always accessible |
| * in higher privilege levels too. Since "Secure PL1" also follows this rule |
| * (ie anything visible in PL2 is visible in S-PL1, some things are only |
| * visible in S-PL1) but "Secure PL1" is a bit of a mouthful, we bend the |
| * terminology a little and call this PL3. |
| * In AArch64 things are somewhat simpler as the PLx bits line up exactly |
| * with the ELx exception levels. |
| * |
| * If access permissions for a register are more complex than can be |
| * described with these bits, then use a laxer set of restrictions, and |
| * do the more restrictive/complex check inside a helper function. |
| */ |
| typedef enum { |
| PL3_R = 0x80, |
| PL3_W = 0x40, |
| PL2_R = 0x20 | PL3_R, |
| PL2_W = 0x10 | PL3_W, |
| PL1_R = 0x08 | PL2_R, |
| PL1_W = 0x04 | PL2_W, |
| PL0_R = 0x02 | PL1_R, |
| PL0_W = 0x01 | PL1_W, |
| |
| /* |
| * For user-mode some registers are accessible to EL0 via a kernel |
| * trap-and-emulate ABI. In this case we define the read permissions |
| * as actually being PL0_R. However some bits of any given register |
| * may still be masked. |
| */ |
| #ifdef CONFIG_USER_ONLY |
| PL0U_R = PL0_R, |
| #else |
| PL0U_R = PL1_R, |
| #endif |
| |
| PL3_RW = PL3_R | PL3_W, |
| PL2_RW = PL2_R | PL2_W, |
| PL1_RW = PL1_R | PL1_W, |
| PL0_RW = PL0_R | PL0_W, |
| } CPAccessRights; |
| |
| typedef enum CPAccessResult { |
| /* Access is permitted */ |
| CP_ACCESS_OK = 0, |
| |
| /* |
| * Combined with one of the following, the low 2 bits indicate the |
| * target exception level. If 0, the exception is taken to the usual |
| * target EL (EL1 or PL1 if in EL0, otherwise to the current EL). |
| */ |
| CP_ACCESS_EL_MASK = 3, |
| |
| /* |
| * Access fails due to a configurable trap or enable which would |
| * result in a categorized exception syndrome giving information about |
| * the failing instruction (ie syndrome category 0x3, 0x4, 0x5, 0x6, |
| * 0xc or 0x18). |
| */ |
| CP_ACCESS_TRAP = (1 << 2), |
| CP_ACCESS_TRAP_EL2 = CP_ACCESS_TRAP | 2, |
| CP_ACCESS_TRAP_EL3 = CP_ACCESS_TRAP | 3, |
| |
| /* |
| * Access fails and results in an exception syndrome 0x0 ("uncategorized"). |
| * Note that this is not a catch-all case -- the set of cases which may |
| * result in this failure is specifically defined by the architecture. |
| */ |
| CP_ACCESS_TRAP_UNCATEGORIZED = (2 << 2), |
| CP_ACCESS_TRAP_UNCATEGORIZED_EL2 = CP_ACCESS_TRAP_UNCATEGORIZED | 2, |
| CP_ACCESS_TRAP_UNCATEGORIZED_EL3 = CP_ACCESS_TRAP_UNCATEGORIZED | 3, |
| } CPAccessResult; |
| |
| typedef struct ARMCPRegInfo ARMCPRegInfo; |
| |
| /* |
| * Access functions for coprocessor registers. These cannot fail and |
| * may not raise exceptions. |
| */ |
| typedef uint64_t CPReadFn(CPUARMState *env, const ARMCPRegInfo *opaque); |
| typedef void CPWriteFn(CPUARMState *env, const ARMCPRegInfo *opaque, |
| uint64_t value); |
| /* Access permission check functions for coprocessor registers. */ |
| typedef CPAccessResult CPAccessFn(CPUARMState *env, |
| const ARMCPRegInfo *opaque, |
| bool isread); |
| /* Hook function for register reset */ |
| typedef void CPResetFn(CPUARMState *env, const ARMCPRegInfo *opaque); |
| |
| #define CP_ANY 0xff |
| |
| /* Definition of an ARM coprocessor register */ |
| struct ARMCPRegInfo { |
| /* Name of register (useful mainly for debugging, need not be unique) */ |
| const char *name; |
| /* |
| * Location of register: coprocessor number and (crn,crm,opc1,opc2) |
| * tuple. Any of crm, opc1 and opc2 may be CP_ANY to indicate a |
| * 'wildcard' field -- any value of that field in the MRC/MCR insn |
| * will be decoded to this register. The register read and write |
| * callbacks will be passed an ARMCPRegInfo with the crn/crm/opc1/opc2 |
| * used by the program, so it is possible to register a wildcard and |
| * then behave differently on read/write if necessary. |
| * For 64 bit registers, only crm and opc1 are relevant; crn and opc2 |
| * must both be zero. |
| * For AArch64-visible registers, opc0 is also used. |
| * Since there are no "coprocessors" in AArch64, cp is purely used as a |
| * way to distinguish (for KVM's benefit) guest-visible system registers |
| * from demuxed ones provided to preserve the "no side effects on |
| * KVM register read/write from QEMU" semantics. cp==0x13 is guest |
| * visible (to match KVM's encoding); cp==0 will be converted to |
| * cp==0x13 when the ARMCPRegInfo is registered, for convenience. |
| */ |
| uint8_t cp; |
| uint8_t crn; |
| uint8_t crm; |
| uint8_t opc0; |
| uint8_t opc1; |
| uint8_t opc2; |
| /* Execution state in which this register is visible: ARM_CP_STATE_* */ |
| CPState state; |
| /* Register type: ARM_CP_* bits/values */ |
| int type; |
| /* Access rights: PL*_[RW] */ |
| CPAccessRights access; |
| /* Security state: ARM_CP_SECSTATE_* bits/values */ |
| CPSecureState secure; |
| /* |
| * The opaque pointer passed to define_arm_cp_regs_with_opaque() when |
| * this register was defined: can be used to hand data through to the |
| * register read/write functions, since they are passed the ARMCPRegInfo*. |
| */ |
| void *opaque; |
| /* |
| * Value of this register, if it is ARM_CP_CONST. Otherwise, if |
| * fieldoffset is non-zero, the reset value of the register. |
| */ |
| uint64_t resetvalue; |
| /* |
| * Offset of the field in CPUARMState for this register. |
| * This is not needed if either: |
| * 1. type is ARM_CP_CONST or one of the ARM_CP_SPECIALs |
| * 2. both readfn and writefn are specified |
| */ |
| ptrdiff_t fieldoffset; /* offsetof(CPUARMState, field) */ |
| |
| /* |
| * Offsets of the secure and non-secure fields in CPUARMState for the |
| * register if it is banked. These fields are only used during the static |
| * registration of a register. During hashing the bank associated |
| * with a given security state is copied to fieldoffset which is used from |
| * there on out. |
| * |
| * It is expected that register definitions use either fieldoffset or |
| * bank_fieldoffsets in the definition but not both. It is also expected |
| * that both bank offsets are set when defining a banked register. This |
| * use indicates that a register is banked. |
| */ |
| ptrdiff_t bank_fieldoffsets[2]; |
| |
| /* |
| * Function for making any access checks for this register in addition to |
| * those specified by the 'access' permissions bits. If NULL, no extra |
| * checks required. The access check is performed at runtime, not at |
| * translate time. |
| */ |
| CPAccessFn *accessfn; |
| /* |
| * Function for handling reads of this register. If NULL, then reads |
| * will be done by loading from the offset into CPUARMState specified |
| * by fieldoffset. |
| */ |
| CPReadFn *readfn; |
| /* |
| * Function for handling writes of this register. If NULL, then writes |
| * will be done by writing to the offset into CPUARMState specified |
| * by fieldoffset. |
| */ |
| CPWriteFn *writefn; |
| /* |
| * Function for doing a "raw" read; used when we need to copy |
| * coprocessor state to the kernel for KVM or out for |
| * migration. This only needs to be provided if there is also a |
| * readfn and it has side effects (for instance clear-on-read bits). |
| */ |
| CPReadFn *raw_readfn; |
| /* |
| * Function for doing a "raw" write; used when we need to copy KVM |
| * kernel coprocessor state into userspace, or for inbound |
| * migration. This only needs to be provided if there is also a |
| * writefn and it masks out "unwritable" bits or has write-one-to-clear |
| * or similar behaviour. |
| */ |
| CPWriteFn *raw_writefn; |
| /* |
| * Function for resetting the register. If NULL, then reset will be done |
| * by writing resetvalue to the field specified in fieldoffset. If |
| * fieldoffset is 0 then no reset will be done. |
| */ |
| CPResetFn *resetfn; |
| |
| /* |
| * "Original" writefn and readfn. |
| * For ARMv8.1-VHE register aliases, we overwrite the read/write |
| * accessor functions of various EL1/EL0 to perform the runtime |
| * check for which sysreg should actually be modified, and then |
| * forwards the operation. Before overwriting the accessors, |
| * the original function is copied here, so that accesses that |
| * really do go to the EL1/EL0 version proceed normally. |
| * (The corresponding EL2 register is linked via opaque.) |
| */ |
| CPReadFn *orig_readfn; |
| CPWriteFn *orig_writefn; |
| }; |
| |
| /* |
| * Macros which are lvalues for the field in CPUARMState for the |
| * ARMCPRegInfo *ri. |
| */ |
| #define CPREG_FIELD32(env, ri) \ |
| (*(uint32_t *)((char *)(env) + (ri)->fieldoffset)) |
| #define CPREG_FIELD64(env, ri) \ |
| (*(uint64_t *)((char *)(env) + (ri)->fieldoffset)) |
| |
| void define_one_arm_cp_reg_with_opaque(ARMCPU *cpu, const ARMCPRegInfo *reg, |
| void *opaque); |
| |
| static inline void define_one_arm_cp_reg(ARMCPU *cpu, const ARMCPRegInfo *regs) |
| { |
| define_one_arm_cp_reg_with_opaque(cpu, regs, NULL); |
| } |
| |
| void define_arm_cp_regs_with_opaque_len(ARMCPU *cpu, const ARMCPRegInfo *regs, |
| void *opaque, size_t len); |
| |
| #define define_arm_cp_regs_with_opaque(CPU, REGS, OPAQUE) \ |
| do { \ |
| QEMU_BUILD_BUG_ON(ARRAY_SIZE(REGS) == 0); \ |
| define_arm_cp_regs_with_opaque_len(CPU, REGS, OPAQUE, \ |
| ARRAY_SIZE(REGS)); \ |
| } while (0) |
| |
| #define define_arm_cp_regs(CPU, REGS) \ |
| define_arm_cp_regs_with_opaque(CPU, REGS, NULL) |
| |
| const ARMCPRegInfo *get_arm_cp_reginfo(GHashTable *cpregs, uint32_t encoded_cp); |
| |
| /* |
| * Definition of an ARM co-processor register as viewed from |
| * userspace. This is used for presenting sanitised versions of |
| * registers to userspace when emulating the Linux AArch64 CPU |
| * ID/feature ABI (advertised as HWCAP_CPUID). |
| */ |
| typedef struct ARMCPRegUserSpaceInfo { |
| /* Name of register */ |
| const char *name; |
| |
| /* Is the name actually a glob pattern */ |
| bool is_glob; |
| |
| /* Only some bits are exported to user space */ |
| uint64_t exported_bits; |
| |
| /* Fixed bits are applied after the mask */ |
| uint64_t fixed_bits; |
| } ARMCPRegUserSpaceInfo; |
| |
| void modify_arm_cp_regs_with_len(ARMCPRegInfo *regs, size_t regs_len, |
| const ARMCPRegUserSpaceInfo *mods, |
| size_t mods_len); |
| |
| #define modify_arm_cp_regs(REGS, MODS) \ |
| do { \ |
| QEMU_BUILD_BUG_ON(ARRAY_SIZE(REGS) == 0); \ |
| QEMU_BUILD_BUG_ON(ARRAY_SIZE(MODS) == 0); \ |
| modify_arm_cp_regs_with_len(REGS, ARRAY_SIZE(REGS), \ |
| MODS, ARRAY_SIZE(MODS)); \ |
| } while (0) |
| |
| /* CPWriteFn that can be used to implement writes-ignored behaviour */ |
| void arm_cp_write_ignore(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value); |
| /* CPReadFn that can be used for read-as-zero behaviour */ |
| uint64_t arm_cp_read_zero(CPUARMState *env, const ARMCPRegInfo *ri); |
| |
| /* |
| * CPResetFn that does nothing, for use if no reset is required even |
| * if fieldoffset is non zero. |
| */ |
| void arm_cp_reset_ignore(CPUARMState *env, const ARMCPRegInfo *opaque); |
| |
| /* |
| * Return true if this reginfo struct's field in the cpu state struct |
| * is 64 bits wide. |
| */ |
| static inline bool cpreg_field_is_64bit(const ARMCPRegInfo *ri) |
| { |
| return (ri->state == ARM_CP_STATE_AA64) || (ri->type & ARM_CP_64BIT); |
| } |
| |
| static inline bool cp_access_ok(int current_el, |
| const ARMCPRegInfo *ri, int isread) |
| { |
| return (ri->access >> ((current_el * 2) + isread)) & 1; |
| } |
| |
| /* Raw read of a coprocessor register (as needed for migration, etc) */ |
| uint64_t read_raw_cp_reg(CPUARMState *env, const ARMCPRegInfo *ri); |
| |
| /* |
| * Return true if the cp register encoding is in the "feature ID space" as |
| * defined by FEAT_IDST (and thus should be reported with ER_ELx.EC |
| * as EC_SYSTEMREGISTERTRAP rather than EC_UNCATEGORIZED). |
| */ |
| static inline bool arm_cpreg_encoding_in_idspace(uint8_t opc0, uint8_t opc1, |
| uint8_t opc2, |
| uint8_t crn, uint8_t crm) |
| { |
| return opc0 == 3 && (opc1 == 0 || opc1 == 1 || opc1 == 3) && |
| crn == 0 && crm < 8; |
| } |
| |
| /* |
| * As arm_cpreg_encoding_in_idspace(), but take the encoding from an |
| * ARMCPRegInfo. |
| */ |
| static inline bool arm_cpreg_in_idspace(const ARMCPRegInfo *ri) |
| { |
| return ri->state == ARM_CP_STATE_AA64 && |
| arm_cpreg_encoding_in_idspace(ri->opc0, ri->opc1, ri->opc2, |
| ri->crn, ri->crm); |
| } |
| |
| #endif /* TARGET_ARM_CPREGS_H */ |
