diff --git a/hw/arm/boot.c b/hw/arm/boot.c index bf97ef3e33..c264864c11 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -575,7 +575,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo, goto fail; } - if (scells < 2 && binfo->ram_size >= (1ULL << 32)) { + if (scells < 2 && binfo->ram_size >= 4 * GiB) { /* This is user error so deserves a friendlier error message * than the failure of setprop_sized_cells would provide */ @@ -754,6 +754,8 @@ static void do_cpu_reset(void *opaque) (cs != first_cpu || !info->secure_board_setup)) { /* Linux expects non-secure state */ env->cp15.scr_el3 |= SCR_NS; + /* Set NSACR.{CP11,CP10} so NS can access the FPU */ + env->cp15.nsacr |= 3 << 10; } } @@ -1095,7 +1097,7 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, * we might still make a bad choice here. */ info->initrd_start = info->loader_start + - MIN(info->ram_size / 2, 128 * 1024 * 1024); + MIN(info->ram_size / 2, 128 * MiB); if (image_high_addr) { info->initrd_start = MAX(info->initrd_start, image_high_addr); } @@ -1155,13 +1157,13 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, * * Let's play safe and prealign it to 2MB to give us some space. */ - align = 2 * 1024 * 1024; + align = 2 * MiB; } else { /* * Some 32bit kernels will trash anything in the 4K page the * initrd ends in, so make sure the DTB isn't caught up in that. */ - align = 4096; + align = 4 * KiB; } /* Place the DTB after the initrd in memory with alignment. */ @@ -1178,7 +1180,7 @@ static void arm_setup_direct_kernel_boot(ARMCPU *cpu, info->loader_start + KERNEL_ARGS_ADDR; fixupcontext[FIXUP_ARGPTR_HI] = (info->loader_start + KERNEL_ARGS_ADDR) >> 32; - if (info->ram_size >= (1ULL << 32)) { + if (info->ram_size >= 4 * GiB) { error_report("RAM size must be less than 4GB to boot" " Linux kernel using ATAGS (try passing a device tree" " using -dtb)"); diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c index 8d65de5b9f..e28c45cd4a 100644 --- a/linux-user/arm/cpu_loop.c +++ b/linux-user/arm/cpu_loop.c @@ -325,9 +325,6 @@ void cpu_loop(CPUARMState *env) if (n == ARM_NR_cacheflush) { /* nop */ - } else if (n == ARM_NR_semihosting - || n == ARM_NR_thumb_semihosting) { - env->regs[0] = do_arm_semihosting (env); } else if (n == 0 || n >= ARM_SYSCALL_BASE || env->thumb) { /* linux syscall */ if (env->thumb || n == 0) { diff --git a/linux-user/arm/target_syscall.h b/linux-user/arm/target_syscall.h index afc0772e19..f85cbdaf56 100644 --- a/linux-user/arm/target_syscall.h +++ b/linux-user/arm/target_syscall.h @@ -18,9 +18,6 @@ struct target_pt_regs { #define ARM_NR_set_tls (ARM_NR_BASE + 5) #define ARM_NR_get_tls (ARM_NR_BASE + 6) -#define ARM_NR_semihosting 0x123456 -#define ARM_NR_thumb_semihosting 0xAB - #if defined(TARGET_WORDS_BIGENDIAN) #define UNAME_MACHINE "armv5teb" #else diff --git a/target/arm/helper.c b/target/arm/helper.c index 507026c915..0d9a2d2ab7 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6733,6 +6733,19 @@ void register_cp_regs_for_features(ARMCPU *cpu) } if (arm_feature(env, ARM_FEATURE_CBAR)) { + /* + * CBAR is IMPDEF, but common on Arm Cortex-A implementations. + * There are two flavours: + * (1) older 32-bit only cores have a simple 32-bit CBAR + * (2) 64-bit cores have a 64-bit CBAR visible to AArch64, plus a + * 32-bit register visible to AArch32 at a different encoding + * to the "flavour 1" register and with the bits rearranged to + * be able to squash a 64-bit address into the 32-bit view. + * We distinguish the two via the ARM_FEATURE_AARCH64 flag, but + * in future if we support AArch32-only configs of some of the + * AArch64 cores we might need to add a specific feature flag + * to indicate cores with "flavour 2" CBAR. + */ if (arm_feature(env, ARM_FEATURE_AARCH64)) { /* 32 bit view is [31:18] 0...0 [43:32]. */ uint32_t cbar32 = (extract64(cpu->reset_cbar, 18, 14) << 18) @@ -6740,12 +6753,12 @@ void register_cp_regs_for_features(ARMCPU *cpu) ARMCPRegInfo cbar_reginfo[] = { { .name = "CBAR", .type = ARM_CP_CONST, - .cp = 15, .crn = 15, .crm = 0, .opc1 = 4, .opc2 = 0, - .access = PL1_R, .resetvalue = cpu->reset_cbar }, + .cp = 15, .crn = 15, .crm = 3, .opc1 = 1, .opc2 = 0, + .access = PL1_R, .resetvalue = cbar32 }, { .name = "CBAR_EL1", .state = ARM_CP_STATE_AA64, .type = ARM_CP_CONST, .opc0 = 3, .opc1 = 1, .crn = 15, .crm = 3, .opc2 = 0, - .access = PL1_R, .resetvalue = cbar32 }, + .access = PL1_R, .resetvalue = cpu->reset_cbar }, REGINFO_SENTINEL }; /* We don't implement a r/w 64 bit CBAR currently */ @@ -8339,88 +8352,32 @@ static void arm_cpu_do_interrupt_aarch64(CPUState *cs) new_el, env->pc, pstate_read(env)); } -static inline bool check_for_semihosting(CPUState *cs) -{ +/* + * Do semihosting call and set the appropriate return value. All the + * permission and validity checks have been done at translate time. + * + * We only see semihosting exceptions in TCG only as they are not + * trapped to the hypervisor in KVM. + */ #ifdef CONFIG_TCG - /* Check whether this exception is a semihosting call; if so - * then handle it and return true; otherwise return false. - */ +static void handle_semihosting(CPUState *cs) +{ ARMCPU *cpu = ARM_CPU(cs); CPUARMState *env = &cpu->env; if (is_a64(env)) { - if (cs->exception_index == EXCP_SEMIHOST) { - /* This is always the 64-bit semihosting exception. - * The "is this usermode" and "is semihosting enabled" - * checks have been done at translate time. - */ - qemu_log_mask(CPU_LOG_INT, - "...handling as semihosting call 0x%" PRIx64 "\n", - env->xregs[0]); - env->xregs[0] = do_arm_semihosting(env); - return true; - } - return false; + qemu_log_mask(CPU_LOG_INT, + "...handling as semihosting call 0x%" PRIx64 "\n", + env->xregs[0]); + env->xregs[0] = do_arm_semihosting(env); } else { - uint32_t imm; - - /* Only intercept calls from privileged modes, to provide some - * semblance of security. - */ - if (cs->exception_index != EXCP_SEMIHOST && - (!semihosting_enabled() || - ((env->uncached_cpsr & CPSR_M) == ARM_CPU_MODE_USR))) { - return false; - } - - switch (cs->exception_index) { - case EXCP_SEMIHOST: - /* This is always a semihosting call; the "is this usermode" - * and "is semihosting enabled" checks have been done at - * translate time. - */ - break; - case EXCP_SWI: - /* Check for semihosting interrupt. */ - if (env->thumb) { - imm = arm_lduw_code(env, env->regs[15] - 2, arm_sctlr_b(env)) - & 0xff; - if (imm == 0xab) { - break; - } - } else { - imm = arm_ldl_code(env, env->regs[15] - 4, arm_sctlr_b(env)) - & 0xffffff; - if (imm == 0x123456) { - break; - } - } - return false; - case EXCP_BKPT: - /* See if this is a semihosting syscall. */ - if (env->thumb) { - imm = arm_lduw_code(env, env->regs[15], arm_sctlr_b(env)) - & 0xff; - if (imm == 0xab) { - env->regs[15] += 2; - break; - } - } - return false; - default: - return false; - } - qemu_log_mask(CPU_LOG_INT, "...handling as semihosting call 0x%x\n", env->regs[0]); env->regs[0] = do_arm_semihosting(env); - return true; } -#else - return false; -#endif } +#endif /* Handle a CPU exception for A and R profile CPUs. * Do any appropriate logging, handle PSCI calls, and then hand off @@ -8451,13 +8408,17 @@ void arm_cpu_do_interrupt(CPUState *cs) return; } - /* Semihosting semantics depend on the register width of the - * code that caused the exception, not the target exception level, - * so must be handled here. + /* + * Semihosting semantics depend on the register width of the code + * that caused the exception, not the target exception level, so + * must be handled here. */ - if (check_for_semihosting(cs)) { +#ifdef CONFIG_TCG + if (cs->exception_index == EXCP_SEMIHOST) { + handle_semihosting(cs); return; } +#endif /* Hooks may change global state so BQL should be held, also the * BQL needs to be held for any modification of diff --git a/target/arm/m_helper.c b/target/arm/m_helper.c index 884d35d2b0..27cd2f3f96 100644 --- a/target/arm/m_helper.c +++ b/target/arm/m_helper.c @@ -2114,19 +2114,13 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) break; } break; + case EXCP_SEMIHOST: + qemu_log_mask(CPU_LOG_INT, + "...handling as semihosting call 0x%x\n", + env->regs[0]); + env->regs[0] = do_arm_semihosting(env); + return; case EXCP_BKPT: - if (semihosting_enabled()) { - int nr; - nr = arm_lduw_code(env, env->regs[15], arm_sctlr_b(env)) & 0xff; - if (nr == 0xab) { - env->regs[15] += 2; - qemu_log_mask(CPU_LOG_INT, - "...handling as semihosting call 0x%x\n", - env->regs[0]); - env->regs[0] = do_arm_semihosting(env); - return; - } - } armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_DEBUG, false); break; case EXCP_IRQ: diff --git a/target/arm/translate.c b/target/arm/translate.c index 34bb280e3d..698c594e8c 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -8424,7 +8424,16 @@ static bool trans_BKPT(DisasContext *s, arg_BKPT *a) if (!ENABLE_ARCH_5) { return false; } - gen_exception_bkpt_insn(s, syn_aa32_bkpt(a->imm, false)); + if (arm_dc_feature(s, ARM_FEATURE_M) && + semihosting_enabled() && +#ifndef CONFIG_USER_ONLY + !IS_USER(s) && +#endif + (a->imm == 0xab)) { + gen_exception_internal_insn(s, s->base.pc_next, EXCP_SEMIHOST); + } else { + gen_exception_bkpt_insn(s, syn_aa32_bkpt(a->imm, false)); + } return true; } @@ -10213,14 +10222,25 @@ static bool trans_CBZ(DisasContext *s, arg_CBZ *a) } /* - * Supervisor call + * Supervisor call - both T32 & A32 come here so we need to check + * which mode we are in when checking for semihosting. */ static bool trans_SVC(DisasContext *s, arg_SVC *a) { - gen_set_pc_im(s, s->base.pc_next); - s->svc_imm = a->imm; - s->base.is_jmp = DISAS_SWI; + const uint32_t semihost_imm = s->thumb ? 0xab : 0x123456; + + if (!arm_dc_feature(s, ARM_FEATURE_M) && semihosting_enabled() && +#ifndef CONFIG_USER_ONLY + !IS_USER(s) && +#endif + (a->imm == semihost_imm)) { + gen_exception_internal_insn(s, s->base.pc_next, EXCP_SEMIHOST); + } else { + gen_set_pc_im(s, s->base.pc_next); + s->svc_imm = a->imm; + s->base.is_jmp = DISAS_SWI; + } return true; } diff --git a/tests/tcg/aarch64/Makefile.target b/tests/tcg/aarch64/Makefile.target index 9758f89f90..509f1afa93 100644 --- a/tests/tcg/aarch64/Makefile.target +++ b/tests/tcg/aarch64/Makefile.target @@ -21,4 +21,9 @@ run-fcvt: fcvt AARCH64_TESTS += pauth-1 pauth-2 run-pauth-%: QEMU_OPTS += -cpu max +# Semihosting smoke test for linux-user +AARCH64_TESTS += semihosting +run-semihosting: semihosting + $(call run-test,$<,$(QEMU) $< 2> $<.err, "$< on $(TARGET_NAME)") + TESTS += $(AARCH64_TESTS) diff --git a/tests/tcg/arm/Makefile.target b/tests/tcg/arm/Makefile.target index 9f43d98f35..3ddff85240 100644 --- a/tests/tcg/arm/Makefile.target +++ b/tests/tcg/arm/Makefile.target @@ -8,7 +8,6 @@ ARM_SRC=$(SRC_PATH)/tests/tcg/arm # Set search path for all sources VPATH += $(ARM_SRC) -# Multiarch Tests float_madds: CFLAGS+=-mfpu=neon-vfpv4 # Basic Hello World @@ -30,6 +29,11 @@ run-fcvt: fcvt $(call run-test,fcvt,$(QEMU) $<,"$< on $(TARGET_NAME)") $(call diff-out,fcvt,$(ARM_SRC)/fcvt.ref) +# Semihosting smoke test for linux-user +ARM_TESTS += semihosting +run-semihosting: semihosting + $(call run-test,$<,$(QEMU) $< 2> $<.err, "$< on $(TARGET_NAME)") + TESTS += $(ARM_TESTS) # On ARM Linux only supports 4k pages diff --git a/tests/tcg/arm/semihosting.c b/tests/tcg/arm/semihosting.c new file mode 100644 index 0000000000..09c89cb481 --- /dev/null +++ b/tests/tcg/arm/semihosting.c @@ -0,0 +1,45 @@ +/* + * linux-user semihosting checks + * + * Copyright (c) 2019 + * Written by Alex Bennée + * + * SPDX-License-Identifier: GPL-3.0-or-later + */ + +#include + +#define SYS_WRITE0 0x04 +#define SYS_REPORTEXC 0x18 + +void __semi_call(uintptr_t type, uintptr_t arg0) +{ +#if defined(__arm__) + register uintptr_t t asm("r0") = type; + register uintptr_t a0 asm("r1") = arg0; + asm("svc 0xab" + : /* no return */ + : "r" (t), "r" (a0)); +#else + register uintptr_t t asm("x0") = type; + register uintptr_t a0 asm("x1") = arg0; + asm("hlt 0xf000" + : /* no return */ + : "r" (t), "r" (a0)); +#endif +} + +int main(int argc, char *argv[argc]) +{ +#if defined(__arm__) + uintptr_t exit_code = 0x20026; +#else + uintptr_t exit_block[2] = {0x20026, 0}; + uintptr_t exit_code = (uintptr_t) &exit_block; +#endif + + __semi_call(SYS_WRITE0, (uintptr_t) "Hello World"); + __semi_call(SYS_REPORTEXC, exit_code); + /* if we get here we failed */ + return -1; +}