diff --git a/include/sbi/sbi_ecall_interface.h b/include/sbi/sbi_ecall_interface.h index a7564d6..cfdf9e1 100644 --- a/include/sbi/sbi_ecall_interface.h +++ b/include/sbi/sbi_ecall_interface.h @@ -22,8 +22,22 @@ enum sbi_ext_id { SBI_EXT_0_1_REMOTE_SFENCE_VMA = 0x6, SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID = 0x7, SBI_EXT_0_1_SHUTDOWN = 0x8, + SBI_EXT_BASE = 0x10, }; +enum sbi_ext_base_fid { + SBI_EXT_BASE_GET_SPEC_VERSION = 0, + SBI_EXT_BASE_GET_IMP_ID, + SBI_EXT_BASE_GET_IMP_VERSION, + SBI_EXT_BASE_PROBE_EXT, + SBI_EXT_BASE_GET_MVENDORID, + SBI_EXT_BASE_GET_MARCHID, + SBI_EXT_BASE_GET_MIMPID, +}; + +#define SBI_SPEC_VERSION_MAJOR_OFFSET 24 +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff /* clang-format on */ #endif diff --git a/lib/sbi/sbi_ecall.c b/lib/sbi/sbi_ecall.c index b8e444f..0a934e9 100644 --- a/lib/sbi/sbi_ecall.c +++ b/lib/sbi/sbi_ecall.c @@ -17,9 +17,12 @@ #include #include #include +#include +#include #define SBI_ECALL_VERSION_MAJOR 0 -#define SBI_ECALL_VERSION_MINOR 1 +#define SBI_ECALL_VERSION_MINOR 2 +#define SBI_OPENSBI_IMPID 1 u16 sbi_ecall_version_major(void) { @@ -31,34 +34,95 @@ u16 sbi_ecall_version_minor(void) return SBI_ECALL_VERSION_MINOR; } -int sbi_ecall_0_1_handler(u32 hartid, struct sbi_trap_regs *regs, - struct sbi_scratch *scratch, - struct unpriv_trap *uptrap) +int sbi_check_extension(struct sbi_scratch *scratch, unsigned long extid, + unsigned long *out_val) +{ + /** + * Each extension apart from base & 0.1, will be implemented as + * platform specific feature. Thus, extension probing can be achieved + * by checking the feature bits of the platform. We can create a map + * between extension ID & feature and use a generic function to check + * or just use a switch case for every new extension support added + * TODO: Implement it. + */ + + if ((extid >= SBI_EXT_0_1_SET_TIMER && + extid <= SBI_EXT_0_1_SHUTDOWN) || (extid == SBI_EXT_BASE)) + *out_val = 1; + else + *out_val = 0; + + return 0; +} + +int sbi_ecall_base_handler(struct sbi_scratch *scratch, unsigned long extid, + unsigned long funcid, unsigned long *args, + unsigned long *out_val, unsigned long *out_tcause, + unsigned long *out_tval) +{ + int ret = 0; + + switch (funcid) { + case SBI_EXT_BASE_GET_SPEC_VERSION: + *out_val = (SBI_ECALL_VERSION_MAJOR << + SBI_SPEC_VERSION_MAJOR_OFFSET) & + (SBI_SPEC_VERSION_MAJOR_MASK << + SBI_SPEC_VERSION_MAJOR_OFFSET); + *out_val = *out_val | SBI_ECALL_VERSION_MINOR; + break; + case SBI_EXT_BASE_GET_IMP_ID: + *out_val = SBI_OPENSBI_IMPID; + break; + case SBI_EXT_BASE_GET_IMP_VERSION: + *out_val = OPENSBI_VERSION; + break; + case SBI_EXT_BASE_GET_MVENDORID: + *out_val = csr_read(CSR_MVENDORID); + break; + case SBI_EXT_BASE_GET_MARCHID: + *out_val = csr_read(CSR_MARCHID); + break; + case SBI_EXT_BASE_GET_MIMPID: + *out_val = csr_read(CSR_MIMPID); + break; + case SBI_EXT_BASE_PROBE_EXT: + ret = sbi_check_extension(scratch, args[0], out_val); + default: + ret = SBI_ENOTSUPP; + } + + return ret; +} + +int sbi_ecall_0_1_handler(struct sbi_scratch *scratch, unsigned long extid, + unsigned long *args, unsigned long *tval, + unsigned long *tcause) { int ret = 0; struct sbi_tlb_info tlb_info; u32 source_hart = sbi_current_hartid(); + struct unpriv_trap uptrap = {0}; - switch (regs->a7) { + switch (extid) { case SBI_EXT_0_1_SET_TIMER: #if __riscv_xlen == 32 sbi_timer_event_start(scratch, - (((u64)regs->a1 << 32) | (u64)regs->a0)); + (((u64)args[1] << 32) | (u64)args[0])); #else - sbi_timer_event_start(scratch, (u64)regs->a0); + sbi_timer_event_start(scratch, (u64)args[0]); #endif break; case SBI_EXT_0_1_CONSOLE_PUTCHAR: - sbi_putc(regs->a0); + sbi_putc(args[0]); break; case SBI_EXT_0_1_CONSOLE_GETCHAR: - regs->a0 = sbi_getc(); + ret = sbi_getc(); break; case SBI_EXT_0_1_CLEAR_IPI: sbi_ipi_clear_smode(scratch); break; case SBI_EXT_0_1_SEND_IPI: - ret = sbi_ipi_send_many(scratch, uptrap, (ulong *)regs->a0, + ret = sbi_ipi_send_many(scratch, &uptrap, (ulong *)args[0], SBI_IPI_EVENT_SOFT, NULL); break; case SBI_EXT_0_1_REMOTE_FENCE_I: @@ -66,26 +130,26 @@ int sbi_ecall_0_1_handler(u32 hartid, struct sbi_trap_regs *regs, tlb_info.size = 0; tlb_info.type = SBI_ITLB_FLUSH; tlb_info.shart_mask = 1UL << source_hart; - ret = sbi_ipi_send_many(scratch, uptrap, (ulong *)regs->a0, + ret = sbi_ipi_send_many(scratch, &uptrap, (ulong *)args[0], SBI_IPI_EVENT_FENCE_I, &tlb_info); break; case SBI_EXT_0_1_REMOTE_SFENCE_VMA: - tlb_info.start = (unsigned long)regs->a1; - tlb_info.size = (unsigned long)regs->a2; + tlb_info.start = (unsigned long)args[1]; + tlb_info.size = (unsigned long)args[2]; tlb_info.type = SBI_TLB_FLUSH_VMA; tlb_info.shart_mask = 1UL << source_hart; - ret = sbi_ipi_send_many(scratch, uptrap, (ulong *)regs->a0, + ret = sbi_ipi_send_many(scratch, &uptrap, (ulong *)args[0], SBI_IPI_EVENT_SFENCE_VMA, &tlb_info); break; case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID: - tlb_info.start = (unsigned long)regs->a1; - tlb_info.size = (unsigned long)regs->a2; - tlb_info.asid = (unsigned long)regs->a3; + tlb_info.start = (unsigned long)args[1]; + tlb_info.size = (unsigned long)args[2]; + tlb_info.asid = (unsigned long)args[3]; tlb_info.type = SBI_TLB_FLUSH_VMA_ASID; tlb_info.shart_mask = 1UL << source_hart; - ret = sbi_ipi_send_many(scratch, uptrap, (ulong *)regs->a0, + ret = sbi_ipi_send_many(scratch, &uptrap, (ulong *)args[0], SBI_IPI_EVENT_SFENCE_VMA_ASID, &tlb_info); break; @@ -93,9 +157,13 @@ int sbi_ecall_0_1_handler(u32 hartid, struct sbi_trap_regs *regs, sbi_system_shutdown(scratch, 0); break; default: - regs->a0 = SBI_ENOTSUPP; + ret = SBI_ENOTSUPP; }; + if (ret == SBI_ETRAP) { + *tcause = uptrap.cause; + *tval = uptrap.tval; + } return ret; } @@ -103,23 +171,49 @@ int sbi_ecall_handler(u32 hartid, ulong mcause, struct sbi_trap_regs *regs, struct sbi_scratch *scratch) { int ret = 0; - struct unpriv_trap uptrap; - u32 extension_id = regs->a7; + unsigned long extension_id = regs->a7; + unsigned long func_id = regs->a6; + unsigned long out_val; + unsigned long out_tval; + unsigned long out_tcause; + bool is_0_1_spec = 0; + unsigned long args[6]; + + args[0] = regs->a0; + args[1] = regs->a1; + args[2] = regs->a2; + args[3] = regs->a3; + args[4] = regs->a4; + args[5] = regs->a5; if (extension_id >= SBI_EXT_0_1_SET_TIMER && extension_id <= SBI_EXT_0_1_SHUTDOWN) { - ret = sbi_ecall_0_1_handler(hartid, regs, scratch, &uptrap); - } else { - regs->a0 = SBI_ENOTSUPP; - } + ret = sbi_ecall_0_1_handler(scratch, extension_id, args, + &out_tval, &out_tcause); + is_0_1_spec = 1; + } else if (extension_id == SBI_EXT_BASE) + ret = sbi_ecall_base_handler(scratch, extension_id, func_id, + args, &out_val, + &out_tval, &out_tcause); + else + ret = SBI_ENOTSUPP; - if (!ret) { - regs->mepc += 4; - } else if (ret == SBI_ETRAP) { - ret = 0; + if (ret == SBI_ETRAP) { sbi_trap_redirect(regs, scratch, regs->mepc, - uptrap.cause, uptrap.tval); + out_tcause, out_tval); + } else { + /* This function should return non-zero value only in case of + * fatal error. However, there is no good way to distinguish + * between a fatal and non-fatal errors yet. That's why we treat + * every return value except ETRAP as non-fatal and just return + * accordingly for now. Once fatal errors are defined, that + * case should be handled differently. + */ + regs->mepc += 4; + regs->a0 = ret; + if (!is_0_1_spec) + regs->a1 = out_val; } - return ret; + return 0; }