From patchwork Tue Jan 28 23:18:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Zhijian Li (Fujitsu)\" via" X-Patchwork-Id: 11355367 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D411814B7 for ; Tue, 28 Jan 2020 23:29:28 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8234A207FD for ; Tue, 28 Jan 2020 23:29:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=keithp.com header.i=@keithp.com header.b="uyBo0WYT"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=keithp.com header.i=@keithp.com header.b="VayVtdOz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8234A207FD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=nongnu.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:38688 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwaIR-00019n-PI for patchwork-qemu-devel@patchwork.kernel.org; Tue, 28 Jan 2020 18:29:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:57638) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwaHe-0000Oh-Jj for qemu-devel@nongnu.org; Tue, 28 Jan 2020 18:28:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iwaHa-0003Mt-8O for qemu-devel@nongnu.org; Tue, 28 Jan 2020 18:28:38 -0500 Received: from home.keithp.com ([63.227.221.253]:44574 helo=elaine.keithp.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iwaHZ-0003Fd-I4; Tue, 28 Jan 2020 18:28:34 -0500 Received: from localhost (localhost [127.0.0.1]) by elaine.keithp.com (Postfix) with ESMTP id 678783F2A89A; Tue, 28 Jan 2020 15:18:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=keithp.com; s=mail; t=1580253527; bh=7Y0B12sjxbCmxcUD7U3lzMcN37ri9JmAhWvA6DIcUk4=; h=From:To:Cc:Subject:Date:From; b=uyBo0WYT/zVcEmU5Iew8EWcgeJR348kKoZ6bYArUzu6lz+qcSggJ5Sw2P9B4RkjXz GLF9HhbLL3H+cvlCwE9Ncu8Juuhm0SnnJCWYdkhJ5lb5kXklpAM9bYtGcn3hgwQpoN EyNwASHGzLKlWUEx4TgNxo6fbSASseTGDeSnxZUoqsAm0EnidVO7hu5E4sT/wPSi8L Mt9GXeI9dzCEMP7r/HTbuJT/+IF00N0c0ydIy/ASORqgJTlHWd+2/5El+jrWu3gc0a cPU0i+s3VWOGA/UxQMX0xkzreBgNkRnWFj1ecvIIj4nRMc6L03/yE7emeSon3TTilV YYDgkwBG5KfNw== X-Virus-Scanned: Debian amavisd-new at keithp.com Received: from elaine.keithp.com ([127.0.0.1]) by localhost (elaine.keithp.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id J-d7V1Gxgh2c; Tue, 28 Jan 2020 15:18:45 -0800 (PST) Received: from keithp.com (koto.keithp.com [10.0.0.2]) by elaine.keithp.com (Postfix) with ESMTPSA id C0EE33F2A895; Tue, 28 Jan 2020 15:18:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=keithp.com; s=mail; t=1580253525; bh=7Y0B12sjxbCmxcUD7U3lzMcN37ri9JmAhWvA6DIcUk4=; h=From:To:Cc:Subject:Date:From; b=VayVtdOz74fstVh6cyoeg4cDIzkYsL0hIDjeuXeK/ogCKUzKlRnrvnCB6+MgYe7GL I364tkmjgHsWYr8Vt3yG+xp6TEAWZ9gGfPLu7bPBnvgtANLMLayTvyhA5iKstafXyW qr9/2v7TDk0/cXOLD7WuoDayIuu/azExblb+hzJdxNw6dQRp8i5pyaQyMXT3SKz2Tc JmvnMtzKkyo20QSsjyrZsP/X7GPkG1hKZU6Eh0MuiIhvcADKQj0mgKkBWurZKMtCBh eY72nejcnBkJsSAcCwiekZsfco0pEzWhSiEv58Bo8mXQyUKwY3KEqRkkIi8Shj/+Zu 3JpEX6MyDouFg== Received: by keithp.com (Postfix, from userid 1000) id A20BB1582162; Tue, 28 Jan 2020 15:18:45 -0800 (PST) To: qemu-devel@nongnu.org Cc: Riku Voipio , Laurent Vivier , Palmer Dabbelt , Alistair Francis , Sagar Karandikar , Bastian Koppelmann , qemu-riscv@nongnu.org, Keith Packard Subject: [PATCH] riscv: Add semihosting support [v3] Date: Tue, 28 Jan 2020 15:18:40 -0800 Message-Id: <20200128231840.508986-1-keithp@keithp.com> X-Mailer: git-send-email 2.25.0 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 63.227.221.253 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Reply-to: Keith Packard X-Patchwork-Original-From: Keith Packard via From: "Zhijian Li (Fujitsu)\" via" Adapt the arm semihosting support code for RISCV. This implementation is based on the standard for RISC-V semihosting as documented in https://riscv.org/specifications/ Signed-off-by: Keith Packard --- v2: Update PC after exception is handled to follow change in the ARM version for SYS_READC v3: Disallow semihosting in user mode; report a regular breakpoint in that case. --- default-configs/riscv32-softmmu.mak | 1 + linux-user/qemu.h | 2 + qemu-options.hx | 4 +- target/riscv/Makefile.objs | 2 +- target/riscv/cpu.h | 2 + target/riscv/cpu_bits.h | 1 + target/riscv/cpu_helper.c | 9 + .../riscv/insn_trans/trans_privileged.inc.c | 23 +- target/riscv/riscv-semi.c | 1073 +++++++++++++++++ target/riscv/translate.c | 11 + 10 files changed, 1124 insertions(+), 4 deletions(-) create mode 100644 target/riscv/riscv-semi.c diff --git a/default-configs/riscv32-softmmu.mak b/default-configs/riscv32-softmmu.mak index 1ae077ed87..21b7bedf19 100644 --- a/default-configs/riscv32-softmmu.mak +++ b/default-configs/riscv32-softmmu.mak @@ -3,6 +3,7 @@ # Uncomment the following lines to disable these optional devices: # #CONFIG_PCI_DEVICES=n +CONFIG_SEMIHOSTING=y # Boards: # diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 560a68090e..122d95d6b6 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -105,6 +105,8 @@ typedef struct TaskState { /* FPA state */ FPA11 fpa; # endif +#endif +#if defined(TARGET_ARM) || defined(TARGET_RISCV) int swi_errno; #endif #if defined(TARGET_I386) && !defined(TARGET_X86_64) diff --git a/qemu-options.hx b/qemu-options.hx index 224a8e8712..4892e6b12c 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4109,7 +4109,7 @@ ETEXI DEF("semihosting", 0, QEMU_OPTION_semihosting, "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | - QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2) + QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2 | QEMU_ARCH_RISCV) STEXI @item -semihosting @findex -semihosting @@ -4119,7 +4119,7 @@ DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, "-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]\n" \ " semihosting configuration\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | -QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2) +QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2 | QEMU_ARCH_RISCV) STEXI @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]] @findex -semihosting-config diff --git a/target/riscv/Makefile.objs b/target/riscv/Makefile.objs index ff651f69f6..6fd7f40e29 100644 --- a/target/riscv/Makefile.objs +++ b/target/riscv/Makefile.objs @@ -1,4 +1,4 @@ -obj-y += translate.o op_helper.o cpu_helper.o cpu.o csr.o fpu_helper.o gdbstub.o +obj-y += translate.o op_helper.o cpu_helper.o cpu.o csr.o fpu_helper.o gdbstub.o riscv-semi.o obj-$(CONFIG_SOFTMMU) += pmp.o ifeq ($(CONFIG_SOFTMMU),y) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index de0a8d893a..310ec6ab40 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -338,6 +338,8 @@ void riscv_cpu_register_gdb_regs_for_features(CPUState *cs); typedef CPURISCVState CPUArchState; typedef RISCVCPU ArchCPU; +target_ulong do_riscv_semihosting(CPURISCVState *env); + #include "exec/cpu-all.h" #endif /* RISCV_CPU_H */ diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h index e99834856c..c45745d73b 100644 --- a/target/riscv/cpu_bits.h +++ b/target/riscv/cpu_bits.h @@ -496,6 +496,7 @@ #define RISCV_EXCP_INST_PAGE_FAULT 0xc /* since: priv-1.10.0 */ #define RISCV_EXCP_LOAD_PAGE_FAULT 0xd /* since: priv-1.10.0 */ #define RISCV_EXCP_STORE_PAGE_FAULT 0xf /* since: priv-1.10.0 */ +#define RISCV_EXCP_SEMIHOST 0x10 #define RISCV_EXCP_INT_FLAG 0x80000000 #define RISCV_EXCP_INT_MASK 0x7fffffff diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 85403da9c8..6a04469936 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -532,6 +532,15 @@ void riscv_cpu_do_interrupt(CPUState *cs) [PRV_M] = RISCV_EXCP_M_ECALL }; + if (cause == RISCV_EXCP_SEMIHOST) { + if (env->priv >= PRV_S) { + env->gpr[xA0] = do_riscv_semihosting(env); + env->pc += 4; + return; + } + cause = RISCV_EXCP_BREAKPOINT; + } + if (!async) { /* set tval to badaddr for traps with address information */ switch (cause) { diff --git a/target/riscv/insn_trans/trans_privileged.inc.c b/target/riscv/insn_trans/trans_privileged.inc.c index c5e4b3e49a..ddc26e889f 100644 --- a/target/riscv/insn_trans/trans_privileged.inc.c +++ b/target/riscv/insn_trans/trans_privileged.inc.c @@ -29,7 +29,28 @@ static bool trans_ecall(DisasContext *ctx, arg_ecall *a) static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a) { - generate_exception(ctx, RISCV_EXCP_BREAKPOINT); + uint32_t pre = opcode_at(&ctx->base, ctx->base.pc_next - 4); + uint32_t ebreak = opcode_at(&ctx->base, ctx->base.pc_next); + uint32_t post = opcode_at(&ctx->base, ctx->base.pc_next + 4); + + /* The RISC-V semihosting spec specifies the following + * three-instruction sequence to flag a semihosting call: + * + * slli zero, zero, 0x1f 0x01f01013 + * ebreak 0x00100073 + * srai zero, zero, 0x7 0x40705013 + * + * The two shift operations on the zero register are no-ops, used + * here to signify a semihosting exception, rather than a breakpoint. + * + * Uncompressed instructions are used so that the sequence is easy + * to validate. + */ + if (pre == 0x01f01013 && ebreak == 0x00100073 && post == 0x40705013) { + generate_exception(ctx, RISCV_EXCP_SEMIHOST); + } else { + generate_exception(ctx, RISCV_EXCP_BREAKPOINT); + } exit_tb(ctx); /* no chaining */ ctx->base.is_jmp = DISAS_NORETURN; return true; diff --git a/target/riscv/riscv-semi.c b/target/riscv/riscv-semi.c new file mode 100644 index 0000000000..60d67a476e --- /dev/null +++ b/target/riscv/riscv-semi.c @@ -0,0 +1,1073 @@ +/* + * RISC-V semihosting syscalls + * + * Copyright (c) 2005, 2007 CodeSourcery. + * Copyright (c) 2019 Linaro + * Copyright © 2019 Keith Packard + * Written by Paul Brook. + * Adapted for RISC-V by Keith Packard + * + * 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 . + * + * ARM Semihosting is documented in: + * Semihosting for AArch32 and AArch64 Release 2.0 + * https://static.docs.arm.com/100863/0200/semihosting.pdf + */ + +#include "qemu/osdep.h" + +#include "cpu.h" +#include "hw/semihosting/semihost.h" +#include "hw/semihosting/console.h" +#include "qemu/log.h" +#ifdef CONFIG_USER_ONLY +#include "qemu.h" + +#define RISCV_HEAP_SIZE (128 * 1024 * 1024) +#else +#include "exec/gdbstub.h" +#include "qemu/cutils.h" +#endif + +#define TARGET_SYS_OPEN 0x01 +#define TARGET_SYS_CLOSE 0x02 +#define TARGET_SYS_WRITEC 0x03 +#define TARGET_SYS_WRITE0 0x04 +#define TARGET_SYS_WRITE 0x05 +#define TARGET_SYS_READ 0x06 +#define TARGET_SYS_READC 0x07 +#define TARGET_SYS_ISTTY 0x09 +#define TARGET_SYS_SEEK 0x0a +#define TARGET_SYS_FLEN 0x0c +#define TARGET_SYS_TMPNAM 0x0d +#define TARGET_SYS_REMOVE 0x0e +#define TARGET_SYS_RENAME 0x0f +#define TARGET_SYS_CLOCK 0x10 +#define TARGET_SYS_TIME 0x11 +#define TARGET_SYS_SYSTEM 0x12 +#define TARGET_SYS_ERRNO 0x13 +#define TARGET_SYS_GET_CMDLINE 0x15 +#define TARGET_SYS_HEAPINFO 0x16 +#define TARGET_SYS_EXIT 0x18 +#define TARGET_SYS_SYNCCACHE 0x19 +#define TARGET_SYS_EXIT_EXTENDED 0x20 + +/* ADP_Stopped_ApplicationExit is used for exit(0), + * anything else is implemented as exit(1) */ +#define ADP_Stopped_ApplicationExit (0x20026) + +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +#define GDB_O_RDONLY 0x000 +#define GDB_O_WRONLY 0x001 +#define GDB_O_RDWR 0x002 +#define GDB_O_APPEND 0x008 +#define GDB_O_CREAT 0x200 +#define GDB_O_TRUNC 0x400 +#define GDB_O_BINARY 0 + +static int gdb_open_modeflags[12] = { + GDB_O_RDONLY, + GDB_O_RDONLY | GDB_O_BINARY, + GDB_O_RDWR, + GDB_O_RDWR | GDB_O_BINARY, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY +}; + +static int open_modeflags[12] = { + O_RDONLY, + O_RDONLY | O_BINARY, + O_RDWR, + O_RDWR | O_BINARY, + O_WRONLY | O_CREAT | O_TRUNC, + O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, + O_RDWR | O_CREAT | O_TRUNC, + O_RDWR | O_CREAT | O_TRUNC | O_BINARY, + O_WRONLY | O_CREAT | O_APPEND, + O_WRONLY | O_CREAT | O_APPEND | O_BINARY, + O_RDWR | O_CREAT | O_APPEND, + O_RDWR | O_CREAT | O_APPEND | O_BINARY +}; + +typedef enum GuestFDType { + GuestFDUnused = 0, + GuestFDHost = 1, + GuestFDGDB = 2, + GuestFDFeatureFile = 3, +} GuestFDType; + +/* + * Guest file descriptors are integer indexes into an array of + * these structures (we will dynamically resize as necessary). + */ +typedef struct GuestFD { + GuestFDType type; + union { + int hostfd; + target_ulong featurefile_offset; + }; +} GuestFD; + +static GArray *guestfd_array; + +/* + * Allocate a new guest file descriptor and return it; if we + * couldn't allocate a new fd then return -1. + * This is a fairly simplistic implementation because we don't + * expect that most semihosting guest programs will make very + * heavy use of opening and closing fds. + */ +static int alloc_guestfd(void) +{ + guint i; + + if (!guestfd_array) { + /* New entries zero-initialized, i.e. type GuestFDUnused */ + guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD)); + } + + for (i = 0; i < guestfd_array->len; i++) { + GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i); + + if (gf->type == GuestFDUnused) { + return i; + } + } + + /* All elements already in use: expand the array */ + g_array_set_size(guestfd_array, i + 1); + return i; +} + +/* + * Look up the guestfd in the data structure; return NULL + * for out of bounds, but don't check whether the slot is unused. + * This is used internally by the other guestfd functions. + */ +static GuestFD *do_get_guestfd(int guestfd) +{ + if (!guestfd_array) { + return NULL; + } + + if (guestfd < 0 || guestfd >= guestfd_array->len) { + return NULL; + } + + return &g_array_index(guestfd_array, GuestFD, guestfd); +} + +/* + * Associate the specified guest fd (which must have been + * allocated via alloc_fd() and not previously used) with + * the specified host/gdb fd. + */ +static void associate_guestfd(int guestfd, int hostfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = use_gdb_syscalls() ? GuestFDGDB : GuestFDHost; + gf->hostfd = hostfd; +} + +/* + * Deallocate the specified guest file descriptor. This doesn't + * close the host fd, it merely undoes the work of alloc_fd(). + */ +static void dealloc_guestfd(int guestfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = GuestFDUnused; +} + +/* + * Given a guest file descriptor, get the associated struct. + * If the fd is not valid, return NULL. This is the function + * used by the various semihosting calls to validate a handle + * from the guest. + * Note: calling alloc_guestfd() or dealloc_guestfd() will + * invalidate any GuestFD* obtained by calling this function. + */ +static GuestFD *get_guestfd(int guestfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + if (!gf || gf->type == GuestFDUnused) { + return NULL; + } + return gf; +} + +/* + * The semihosting API has no concept of its errno being thread-safe, + * as the API design predates SMP CPUs and was intended as a simple + * real-hardware set of debug functionality. For QEMU, we make the + * errno be per-thread in linux-user mode; in softmmu it is a simple + * global, and we assume that the guest takes care of avoiding any races. + */ +#ifndef CONFIG_USER_ONLY +static target_ulong syscall_err; + +#include "exec/softmmu-semi.h" +#endif + +static inline uint32_t set_swi_errno(CPURISCVState *env, uint32_t code) +{ + if (code == (uint32_t)-1) { +#ifdef CONFIG_USER_ONLY + CPUState *cs = env_cpu(env); + TaskState *ts = cs->opaque; + + ts->swi_errno = errno; +#else + syscall_err = errno; +#endif + } + return code; +} + +static inline uint32_t get_swi_errno(CPURISCVState *env) +{ +#ifdef CONFIG_USER_ONLY + CPUState *cs = env_cpu(env); + TaskState *ts = cs->opaque; + + return ts->swi_errno; +#else + return syscall_err; +#endif +} + +static target_ulong riscv_semi_syscall_len; + +static void riscv_semi_cb(CPUState *cs, target_ulong ret, target_ulong err) +{ + RISCVCPU *cpu = RISCV_CPU(cs); + CPURISCVState *env = &cpu->env; + target_ulong reg0 = env->gpr[xA0]; + + if (ret == (target_ulong)-1) { + errno = err; + set_swi_errno(env, -1); + reg0 = ret; + } else { + /* Fixup syscalls that use nonstardard return conventions. */ + switch (reg0) { + case TARGET_SYS_WRITE: + case TARGET_SYS_READ: + reg0 = riscv_semi_syscall_len - ret; + break; + case TARGET_SYS_SEEK: + reg0 = 0; + break; + default: + reg0 = ret; + break; + } + } + env->gpr[xA0] = reg0; +} + +static target_ulong riscv_flen_buf(RISCVCPU *cpu) +{ + /* Return an address in target memory of 64 bytes where the remote + * gdb should write its stat struct. (The format of this structure + * is defined by GDB's remote protocol and is not target-specific.) + * We put this on the guest's stack just below SP. + */ + CPURISCVState *env = &cpu->env; + target_ulong sp; + + sp = env->gpr[xSP]; + + return sp - 64; +} + +static void riscv_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err) +{ + RISCVCPU *cpu = RISCV_CPU(cs); + CPURISCVState *env = &cpu->env; + /* The size is always stored in big-endian order, extract + the value. We assume the size always fit in 32 bits. */ + uint32_t size; + cpu_memory_rw_debug(cs, riscv_flen_buf(cpu) + 32, (uint8_t *)&size, 4, 0); + size = be32_to_cpu(size); + env->gpr[xA0] = size; + errno = err; + set_swi_errno(env, -1); +} + +static int riscv_semi_open_guestfd; + +static void riscv_semi_open_cb(CPUState *cs, target_ulong ret, target_ulong err) +{ + RISCVCPU *cpu = RISCV_CPU(cs); + CPURISCVState *env = &cpu->env; + if (ret == (target_ulong)-1) { + errno = err; + set_swi_errno(env, -1); + dealloc_guestfd(riscv_semi_open_guestfd); + } else { + associate_guestfd(riscv_semi_open_guestfd, ret); + ret = riscv_semi_open_guestfd; + } + + env->gpr[xA0] = ret; +} + +static target_ulong riscv_gdb_syscall(RISCVCPU *cpu, gdb_syscall_complete_cb cb, + const char *fmt, ...) +{ + va_list va; + CPURISCVState *env = &cpu->env; + + va_start(va, fmt); + gdb_do_syscallv(cb, fmt, va); + va_end(va); + + /* + * FIXME: in softmmu mode, the gdbstub will schedule our callback + * to occur, but will not actually call it to complete the syscall + * until after this function has returned and we are back in the + * CPU main loop. Therefore callers to this function must not + * do anything with its return value, because it is not necessarily + * the result of the syscall, but could just be the old value of X0. + * The only thing safe to do with this is that the callers of + * do_riscv_semihosting() will write it straight back into X0. + * (In linux-user mode, the callback will have happened before + * gdb_do_syscallv() returns.) + * + * We should tidy this up so neither this function nor + * do_riscv_semihosting() return a value, so the mistake of + * doing something with the return value is not possible to make. + */ + + return env->gpr[xA0]; +} + +/* + * Types for functions implementing various semihosting calls + * for specific types of guest file descriptor. These must all + * do the work and return the required return value for the guest, + * setting the guest errno if appropriate. + */ +typedef uint32_t sys_closefn(RISCVCPU *cpu, GuestFD *gf); +typedef uint32_t sys_writefn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len); +typedef uint32_t sys_readfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len); +typedef uint32_t sys_isattyfn(RISCVCPU *cpu, GuestFD *gf); +typedef uint32_t sys_seekfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong offset); +typedef uint32_t sys_flenfn(RISCVCPU *cpu, GuestFD *gf); + +static uint32_t host_closefn(RISCVCPU *cpu, GuestFD *gf) +{ + CPURISCVState *env = &cpu->env; + + return set_swi_errno(env, close(gf->hostfd)); +} + +static uint32_t host_writefn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + uint32_t ret; + CPURISCVState *env = &cpu->env; + char *s = lock_user(VERIFY_READ, buf, len, 1); + if (!s) { + /* Return bytes not written on error */ + return len; + } + ret = set_swi_errno(env, write(gf->hostfd, s, len)); + unlock_user(s, buf, 0); + if (ret == (uint32_t)-1) { + ret = 0; + } + /* Return bytes not written */ + return len - ret; +} + +static uint32_t host_readfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + uint32_t ret; + CPURISCVState *env = &cpu->env; + char *s = lock_user(VERIFY_WRITE, buf, len, 0); + if (!s) { + /* return bytes not read */ + return len; + } + do { + ret = set_swi_errno(env, read(gf->hostfd, s, len)); + } while (ret == -1 && errno == EINTR); + unlock_user(s, buf, len); + if (ret == (uint32_t)-1) { + ret = 0; + } + /* Return bytes not read */ + return len - ret; +} + +static uint32_t host_isattyfn(RISCVCPU *cpu, GuestFD *gf) +{ + return isatty(gf->hostfd); +} + +static uint32_t host_seekfn(RISCVCPU *cpu, GuestFD *gf, target_ulong offset) +{ + CPURISCVState *env = &cpu->env; + uint32_t ret = set_swi_errno(env, lseek(gf->hostfd, offset, SEEK_SET)); + if (ret == (uint32_t)-1) { + return -1; + } + return 0; +} + +static uint32_t host_flenfn(RISCVCPU *cpu, GuestFD *gf) +{ + CPURISCVState *env = &cpu->env; + struct stat buf; + uint32_t ret = set_swi_errno(env, fstat(gf->hostfd, &buf)); + if (ret == (uint32_t)-1) { + return -1; + } + return buf.st_size; +} + +static uint32_t gdb_closefn(RISCVCPU *cpu, GuestFD *gf) +{ + return riscv_gdb_syscall(cpu, riscv_semi_cb, "close,%x", gf->hostfd); +} + +static uint32_t gdb_writefn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + riscv_semi_syscall_len = len; + return riscv_gdb_syscall(cpu, riscv_semi_cb, "write,%x,%x,%x", + gf->hostfd, buf, len); +} + +static uint32_t gdb_readfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + riscv_semi_syscall_len = len; + return riscv_gdb_syscall(cpu, riscv_semi_cb, "read,%x,%x,%x", + gf->hostfd, buf, len); +} + +static uint32_t gdb_isattyfn(RISCVCPU *cpu, GuestFD *gf) +{ + return riscv_gdb_syscall(cpu, riscv_semi_cb, "isatty,%x", gf->hostfd); +} + +static uint32_t gdb_seekfn(RISCVCPU *cpu, GuestFD *gf, target_ulong offset) +{ + return riscv_gdb_syscall(cpu, riscv_semi_cb, "lseek,%x,%x,0", + gf->hostfd, offset); +} + +static uint32_t gdb_flenfn(RISCVCPU *cpu, GuestFD *gf) +{ + return riscv_gdb_syscall(cpu, riscv_semi_flen_cb, "fstat,%x,%x", + gf->hostfd, riscv_flen_buf(cpu)); +} + +#define SHFB_MAGIC_0 0x53 +#define SHFB_MAGIC_1 0x48 +#define SHFB_MAGIC_2 0x46 +#define SHFB_MAGIC_3 0x42 + +/* Feature bits reportable in feature byte 0 */ +#define SH_EXT_EXIT_EXTENDED (1 << 0) +#define SH_EXT_STDOUT_STDERR (1 << 1) + +static const uint8_t featurefile_data[] = { + SHFB_MAGIC_0, + SHFB_MAGIC_1, + SHFB_MAGIC_2, + SHFB_MAGIC_3, + SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */ +}; + +static void init_featurefile_guestfd(int guestfd) +{ + GuestFD *gf = do_get_guestfd(guestfd); + + assert(gf); + gf->type = GuestFDFeatureFile; + gf->featurefile_offset = 0; +} + +static uint32_t featurefile_closefn(RISCVCPU *cpu, GuestFD *gf) +{ + /* Nothing to do */ + return 0; +} + +static uint32_t featurefile_writefn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + /* This fd can never be open for writing */ + CPURISCVState *env = &cpu->env; + + errno = EBADF; + return set_swi_errno(env, -1); +} + +static uint32_t featurefile_readfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong buf, uint32_t len) +{ + uint32_t i; +#ifndef CONFIG_USER_ONLY + CPURISCVState *env = &cpu->env; +#endif + char *s; + + s = lock_user(VERIFY_WRITE, buf, len, 0); + if (!s) { + return len; + } + + for (i = 0; i < len; i++) { + if (gf->featurefile_offset >= sizeof(featurefile_data)) { + break; + } + s[i] = featurefile_data[gf->featurefile_offset]; + gf->featurefile_offset++; + } + + unlock_user(s, buf, len); + + /* Return number of bytes not read */ + return len - i; +} + +static uint32_t featurefile_isattyfn(RISCVCPU *cpu, GuestFD *gf) +{ + return 0; +} + +static uint32_t featurefile_seekfn(RISCVCPU *cpu, GuestFD *gf, + target_ulong offset) +{ + gf->featurefile_offset = offset; + return 0; +} + +static uint32_t featurefile_flenfn(RISCVCPU *cpu, GuestFD *gf) +{ + return sizeof(featurefile_data); +} + +typedef struct GuestFDFunctions { + sys_closefn *closefn; + sys_writefn *writefn; + sys_readfn *readfn; + sys_isattyfn *isattyfn; + sys_seekfn *seekfn; + sys_flenfn *flenfn; +} GuestFDFunctions; + +static const GuestFDFunctions guestfd_fns[] = { + [GuestFDHost] = { + .closefn = host_closefn, + .writefn = host_writefn, + .readfn = host_readfn, + .isattyfn = host_isattyfn, + .seekfn = host_seekfn, + .flenfn = host_flenfn, + }, + [GuestFDGDB] = { + .closefn = gdb_closefn, + .writefn = gdb_writefn, + .readfn = gdb_readfn, + .isattyfn = gdb_isattyfn, + .seekfn = gdb_seekfn, + .flenfn = gdb_flenfn, + }, + [GuestFDFeatureFile] = { + .closefn = featurefile_closefn, + .writefn = featurefile_writefn, + .readfn = featurefile_readfn, + .isattyfn = featurefile_isattyfn, + .seekfn = featurefile_seekfn, + .flenfn = featurefile_flenfn, + }, +}; + +/* Read the input value from the argument block; fail the semihosting + * call if the memory read fails. + */ +#define GET_ARG(n) do { \ + if (get_user_ual(arg ## n, args + (n) * sizeof(target_ulong))) { \ + errno = EFAULT; \ + return set_swi_errno(env, -1); \ + } \ + } while (0) + +#define SET_ARG(n, val) \ + put_user_ual(val, args + (n) * sizeof(target_ulong)) + +/* + * Do a semihosting call. + * + * The specification always says that the "return register" either + * returns a specific value or is corrupted, so we don't need to + * report to our caller whether we are returning a value or trying to + * leave the register unchanged. We use 0xdeadbeef as the return value + * when there isn't a defined return value for the call. + */ +target_ulong do_riscv_semihosting(CPURISCVState *env) +{ + RISCVCPU *cpu = env_archcpu(env); + CPUState *cs = env_cpu(env); + target_ulong args; + target_ulong arg0, arg1, arg2, arg3; + char * s; + int nr; + uint32_t ret; + uint32_t len; + GuestFD *gf; + + nr = env->gpr[xA0] & 0xffffffffU; + args = env->gpr[xA1]; + + switch (nr) { + case TARGET_SYS_OPEN: + { + int guestfd; + + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + s = lock_user_string(arg0); + if (!s) { + errno = EFAULT; + return set_swi_errno(env, -1); + } + if (arg1 >= 12) { + unlock_user(s, arg0, 0); + errno = EINVAL; + return set_swi_errno(env, -1); + } + + guestfd = alloc_guestfd(); + if (guestfd < 0) { + unlock_user(s, arg0, 0); + errno = EMFILE; + return set_swi_errno(env, -1); + } + + if (strcmp(s, ":tt") == 0) { + int result_fileno; + + /* + * We implement SH_EXT_STDOUT_STDERR, so: + * open for read == stdin + * open for write == stdout + * open for append == stderr + */ + if (arg1 < 4) { + result_fileno = STDIN_FILENO; + } else if (arg1 < 8) { + result_fileno = STDOUT_FILENO; + } else { + result_fileno = STDERR_FILENO; + } + associate_guestfd(guestfd, result_fileno); + unlock_user(s, arg0, 0); + return guestfd; + } + if (strcmp(s, ":semihosting-features") == 0) { + unlock_user(s, arg0, 0); + /* We must fail opens for modes other than 0 ('r') or 1 ('rb') */ + if (arg1 != 0 && arg1 != 1) { + dealloc_guestfd(guestfd); + errno = EACCES; + return set_swi_errno(env, -1); + } + init_featurefile_guestfd(guestfd); + return guestfd; + } + + if (use_gdb_syscalls()) { + riscv_semi_open_guestfd = guestfd; + ret = riscv_gdb_syscall(cpu, riscv_semi_open_cb, "open,%s,%x,1a4", arg0, + (int)arg2+1, gdb_open_modeflags[arg1]); + } else { + ret = set_swi_errno(env, open(s, open_modeflags[arg1], 0644)); + if (ret == (uint32_t)-1) { + dealloc_guestfd(guestfd); + } else { + associate_guestfd(guestfd, ret); + ret = guestfd; + } + } + unlock_user(s, arg0, 0); + return ret; + } + case TARGET_SYS_CLOSE: + GET_ARG(0); + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + ret = guestfd_fns[gf->type].closefn(cpu, gf); + dealloc_guestfd(arg0); + return ret; + case TARGET_SYS_WRITEC: + qemu_semihosting_console_outc(env, args); + return 0xdeadbeef; + case TARGET_SYS_WRITE0: + return qemu_semihosting_console_outs(env, args); + case TARGET_SYS_WRITE: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + len = arg2; + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + return guestfd_fns[gf->type].writefn(cpu, gf, arg1, len); + case TARGET_SYS_READ: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + len = arg2; + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + return guestfd_fns[gf->type].readfn(cpu, gf, arg1, len); + case TARGET_SYS_READC: + return qemu_semihosting_console_inc(env); + case TARGET_SYS_ISTTY: + GET_ARG(0); + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + return guestfd_fns[gf->type].isattyfn(cpu, gf); + case TARGET_SYS_SEEK: + GET_ARG(0); + GET_ARG(1); + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + return guestfd_fns[gf->type].seekfn(cpu, gf, arg1); + case TARGET_SYS_FLEN: + GET_ARG(0); + + gf = get_guestfd(arg0); + if (!gf) { + errno = EBADF; + return set_swi_errno(env, -1); + } + + return guestfd_fns[gf->type].flenfn(cpu, gf); + case TARGET_SYS_TMPNAM: + qemu_log_mask(LOG_UNIMP, "%s: SYS_TMPNAM not implemented", __func__); + return -1; + case TARGET_SYS_REMOVE: + GET_ARG(0); + GET_ARG(1); + if (use_gdb_syscalls()) { + ret = riscv_gdb_syscall(cpu, riscv_semi_cb, "unlink,%s", + arg0, (int)arg1+1); + } else { + s = lock_user_string(arg0); + if (!s) { + errno = EFAULT; + return set_swi_errno(env, -1); + } + ret = set_swi_errno(env, remove(s)); + unlock_user(s, arg0, 0); + } + return ret; + case TARGET_SYS_RENAME: + GET_ARG(0); + GET_ARG(1); + GET_ARG(2); + GET_ARG(3); + if (use_gdb_syscalls()) { + return riscv_gdb_syscall(cpu, riscv_semi_cb, "rename,%s,%s", + arg0, (int)arg1+1, arg2, (int)arg3+1); + } else { + char *s2; + s = lock_user_string(arg0); + s2 = lock_user_string(arg2); + if (!s || !s2) { + errno = EFAULT; + ret = set_swi_errno(env, -1); + } else { + ret = set_swi_errno(env, rename(s, s2)); + } + if (s2) + unlock_user(s2, arg2, 0); + if (s) + unlock_user(s, arg0, 0); + return ret; + } + case TARGET_SYS_CLOCK: + return clock() / (CLOCKS_PER_SEC / 100); + case TARGET_SYS_TIME: + return set_swi_errno(env, time(NULL)); + case TARGET_SYS_SYSTEM: + GET_ARG(0); + GET_ARG(1); + if (use_gdb_syscalls()) { + return riscv_gdb_syscall(cpu, riscv_semi_cb, "system,%s", + arg0, (int)arg1+1); + } else { + s = lock_user_string(arg0); + if (!s) { + errno = EFAULT; + return set_swi_errno(env, -1); + } + ret = set_swi_errno(env, system(s)); + unlock_user(s, arg0, 0); + return ret; + } + case TARGET_SYS_ERRNO: + return get_swi_errno(env); + case TARGET_SYS_GET_CMDLINE: + { + /* Build a command-line from the original argv. + * + * The inputs are: + * * arg0, pointer to a buffer of at least the size + * specified in arg1. + * * arg1, size of the buffer pointed to by arg0 in + * bytes. + * + * The outputs are: + * * arg0, pointer to null-terminated string of the + * command line. + * * arg1, length of the string pointed to by arg0. + */ + + char *output_buffer; + size_t input_size; + size_t output_size; + int status = 0; +#if !defined(CONFIG_USER_ONLY) + const char *cmdline; +#else + TaskState *ts = cs->opaque; +#endif + GET_ARG(0); + GET_ARG(1); + input_size = arg1; + /* Compute the size of the output string. */ +#if !defined(CONFIG_USER_ONLY) + cmdline = semihosting_get_cmdline(); + if (cmdline == NULL) { + cmdline = ""; /* Default to an empty line. */ + } + output_size = strlen(cmdline) + 1; /* Count terminating 0. */ +#else + unsigned int i; + + output_size = ts->info->arg_end - ts->info->arg_start; + if (!output_size) { + /* + * We special-case the "empty command line" case (argc==0). + * Just provide the terminating 0. + */ + output_size = 1; + } +#endif + + if (output_size > input_size) { + /* Not enough space to store command-line arguments. */ + errno = E2BIG; + return set_swi_errno(env, -1); + } + + /* Adjust the command-line length. */ + if (SET_ARG(1, output_size - 1)) { + /* Couldn't write back to argument block */ + errno = EFAULT; + return set_swi_errno(env, -1); + } + + /* Lock the buffer on the RISC-V side. */ + output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0); + if (!output_buffer) { + errno = EFAULT; + return set_swi_errno(env, -1); + } + + /* Copy the command-line arguments. */ +#if !defined(CONFIG_USER_ONLY) + pstrcpy(output_buffer, output_size, cmdline); +#else + if (output_size == 1) { + /* Empty command-line. */ + output_buffer[0] = '\0'; + goto out; + } + + if (copy_from_user(output_buffer, ts->info->arg_start, + output_size)) { + errno = EFAULT; + status = set_swi_errno(env, -1); + goto out; + } + + /* Separate arguments by white spaces. */ + for (i = 0; i < output_size - 1; i++) { + if (output_buffer[i] == 0) { + output_buffer[i] = ' '; + } + } + out: +#endif + /* Unlock the buffer on the RISC-V side. */ + unlock_user(output_buffer, arg0, output_size); + + return status; + } + case TARGET_SYS_HEAPINFO: + { + target_ulong retvals[4]; + target_ulong limit; + int i; +#ifdef CONFIG_USER_ONLY + TaskState *ts = cs->opaque; +#endif + + GET_ARG(0); + +#ifdef CONFIG_USER_ONLY + /* + * Some C libraries assume the heap immediately follows .bss, so + * allocate it using sbrk. + */ + if (!ts->heap_limit) { + abi_ulong ret; + + ts->heap_base = do_brk(0); + limit = ts->heap_base + RISCV_HEAP_SIZE; + /* Try a big heap, and reduce the size if that fails. */ + for (;;) { + ret = do_brk(limit); + if (ret >= limit) { + break; + } + limit = (ts->heap_base >> 1) + (limit >> 1); + } + ts->heap_limit = limit; + } + + retvals[0] = ts->heap_base; + retvals[1] = ts->heap_limit; + retvals[2] = ts->stack_base; + retvals[3] = 0; /* Stack limit. */ +#else + limit = ram_size; + /* TODO: Make this use the limit of the loaded application. */ + retvals[0] = limit / 2; + retvals[1] = limit; + retvals[2] = limit; /* Stack base */ + retvals[3] = 0; /* Stack limit. */ +#endif + + for (i = 0; i < ARRAY_SIZE(retvals); i++) { + bool fail; + + fail = put_user_ual(retvals[i], arg0 + i * sizeof(target_ulong)); + + if (fail) { + /* Couldn't write back to argument block */ + errno = EFAULT; + return set_swi_errno(env, -1); + } + } + return 0; + } + case TARGET_SYS_EXIT: + case TARGET_SYS_EXIT_EXTENDED: + if (nr == TARGET_SYS_EXIT_EXTENDED || sizeof(target_ulong) == 0) { + /* + * The A64 version of SYS_EXIT takes a parameter block, + * so the application-exit type can return a subcode which + * is the exit status code from the application. + * SYS_EXIT_EXTENDED is an a new-in-v2.0 optional function + * which allows A32/T32 guests to also provide a status code. + */ + GET_ARG(0); + GET_ARG(1); + + if (arg0 == ADP_Stopped_ApplicationExit) { + ret = arg1; + } else { + ret = 1; + } + } else { + /* + * The A32/T32 version of SYS_EXIT specifies only + * Stopped_ApplicationExit as normal exit, but does not + * allow the guest to specify the exit status code. + * Everything else is considered an error. + */ + ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1; + } + gdb_exit(env, ret); + exit(ret); + case TARGET_SYS_SYNCCACHE: + /* + * Clean the D-cache and invalidate the I-cache for the specified + * virtual address range. This is a nop for us since we don't + * implement caches. This is only present on A64. + */ + if (sizeof(target_ulong) == 8) { + return 0; + } + /* fall through -- invalid for A32/T32 */ + default: + fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr); + cpu_dump_state(cs, stderr, 0); + abort(); + } +} diff --git a/target/riscv/translate.c b/target/riscv/translate.c index 14dc71156b..4ee0d75f86 100644 --- a/target/riscv/translate.c +++ b/target/riscv/translate.c @@ -55,6 +55,7 @@ typedef struct DisasContext { to reset this known value. */ int frm; bool ext_ifencei; + CPUState *cs; } DisasContext; #ifdef TARGET_RISCV64 @@ -698,6 +699,15 @@ static bool gen_shift(DisasContext *ctx, arg_r *a, return true; } +static uint32_t opcode_at(DisasContextBase *dcbase, target_ulong pc) +{ + DisasContext *ctx = container_of(dcbase, DisasContext, base); + CPUState *cpu = ctx->cs; + CPURISCVState *env = cpu->env_ptr; + + return cpu_ldl_code(env, pc); +} + /* Include insn module translation function */ #include "insn_trans/trans_rvi.inc.c" #include "insn_trans/trans_rvm.inc.c" @@ -743,6 +753,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) ctx->misa = env->misa; ctx->frm = -1; /* unknown rounding mode */ ctx->ext_ifencei = cpu->cfg.ext_ifencei; + ctx->cs = cs; } static void riscv_tr_tb_start(DisasContextBase *db, CPUState *cpu)