技巧

• • • • 1、 在linux kernel中讀寫ARM寄存器示例
      • 2、 在optee中讀寫ARM寄存器示例
      • 3、自定義log打印函數

1、 在linux kernel中讀寫ARM寄存器示例

#define FUNCTION_INVARIANT(reg) \static void get_##reg(struct kvm_vcpu *v, \const struct sys_reg_desc *r) \{ \u64 val; \\asm volatile("mrs %0, " __stringify(reg) "\n" \: "=r" (val)); \((struct sys_reg_desc *)r)->val = val; \}FUNCTION_INVARIANT(midr_el1) FUNCTION_INVARIANT(ctr_el0) FUNCTION_INVARIANT(revidr_el1) FUNCTION_INVARIANT(id_pfr0_el1) FUNCTION_INVARIANT(id_pfr1_el1) FUNCTION_INVARIANT(id_dfr0_el1) FUNCTION_INVARIANT(id_afr0_el1) FUNCTION_INVARIANT(id_mmfr0_el1) FUNCTION_INVARIANT(id_mmfr1_el1) FUNCTION_INVARIANT(id_mmfr2_el1) FUNCTION_INVARIANT(id_mmfr3_el1) FUNCTION_INVARIANT(id_isar0_el1) FUNCTION_INVARIANT(id_isar1_el1) FUNCTION_INVARIANT(id_isar2_el1) FUNCTION_INVARIANT(id_isar3_el1) FUNCTION_INVARIANT(id_isar4_el1) FUNCTION_INVARIANT(id_isar5_el1) FUNCTION_INVARIANT(clidr_el1) FUNCTION_INVARIANT(aidr_el1)

2、 在optee中讀寫ARM寄存器示例

#define DEFINE_REG_READ_FUNC_(reg, type, asmreg) \ static inline type read_##reg(void) \ { \type val; \\asm volatile("mrs %0, " #asmreg : "=r" (val)); \return val; \ }#define DEFINE_REG_WRITE_FUNC_(reg, type, asmreg) \ static inline void write_##reg(type val) \ { \asm volatile("msr " #asmreg ", %0" : : "r" (val)); \ }#define DEFINE_U32_REG_READ_FUNC(reg) \DEFINE_REG_READ_FUNC_(reg, uint32_t, reg)#define DEFINE_U32_REG_WRITE_FUNC(reg) \DEFINE_REG_WRITE_FUNC_(reg, uint32_t, reg)#define DEFINE_U32_REG_READWRITE_FUNCS(reg) \DEFINE_U32_REG_READ_FUNC(reg) \DEFINE_U32_REG_WRITE_FUNC(reg)#define DEFINE_U64_REG_READ_FUNC(reg) \DEFINE_REG_READ_FUNC_(reg, uint64_t, reg)#define DEFINE_U64_REG_WRITE_FUNC(reg) \DEFINE_REG_WRITE_FUNC_(reg, uint64_t, reg)#define DEFINE_U64_REG_READWRITE_FUNCS(reg) \DEFINE_U64_REG_READ_FUNC(reg) \DEFINE_U64_REG_WRITE_FUNC(reg)DEFINE_U32_REG_READWRITE_FUNCS(cpacr_el1) DEFINE_U32_REG_READWRITE_FUNCS(daif) DEFINE_U32_REG_READWRITE_FUNCS(fpcr) DEFINE_U32_REG_READWRITE_FUNCS(fpsr)DEFINE_U32_REG_READ_FUNC(contextidr_el1) DEFINE_U32_REG_READ_FUNC(sctlr_el1)/* ARM Generic timer functions */ DEFINE_REG_READ_FUNC_(cntfrq, uint32_t, cntfrq_el0) DEFINE_REG_READ_FUNC_(cntpct, uint64_t, cntpct_el0) DEFINE_REG_READ_FUNC_(cntkctl, uint32_t, cntkctl_el1) DEFINE_REG_WRITE_FUNC_(cntkctl, uint32_t, cntkctl_el1)DEFINE_U64_REG_READWRITE_FUNCS(ttbr0_el1) DEFINE_U64_REG_READWRITE_FUNCS(ttbr1_el1) DEFINE_U64_REG_READWRITE_FUNCS(tcr_el1)DEFINE_U64_REG_READ_FUNC(esr_el1) DEFINE_U64_REG_READ_FUNC(far_el1) DEFINE_U64_REG_READ_FUNC(mpidr_el1) DEFINE_U64_REG_READ_FUNC(midr_el1) /* Alias for reading this register to avoid ifdefs in code */ #define read_midr() read_midr_el1() DEFINE_U64_REG_READ_FUNC(par_el1)DEFINE_U64_REG_WRITE_FUNC(mair_el1)/* Register read/write functions for GICC registers by using system interface */ DEFINE_REG_READ_FUNC_(icc_ctlr, uint32_t, S3_0_C12_C12_4) DEFINE_REG_WRITE_FUNC_(icc_ctlr, uint32_t, S3_0_C12_C12_4) DEFINE_REG_WRITE_FUNC_(icc_pmr, uint32_t, S3_0_C4_C6_0) DEFINE_REG_READ_FUNC_(icc_iar0, uint32_t, S3_0_c12_c8_0) DEFINE_REG_READ_FUNC_(icc_iar1, uint32_t, S3_0_c12_c12_0) DEFINE_REG_WRITE_FUNC_(icc_eoir0, uint32_t, S3_0_c12_c8_1) DEFINE_REG_WRITE_FUNC_(icc_eoir1, uint32_t, S3_0_c12_c12_1)

3、自定義log打印函數

#define XXXX_PRINTK(fmt, ...) ALOGI(fmt, ##__VA_ARGS__) #define XXXX_ENTER() XXXX_PRINTK("%d : %s :enter",__LINE__, __func__) #define XXXX_EXIT() XXXX_PRINTK("%d : %s :exit",__LINE__, __func__)

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