* [PATCH 3/9] semihosting: Change internal common-semi interfaces to use CPUState *
2021-01-07 17:07 [PATCH 0/9] Add RISC-V semihosting 0.2. Finish ARM semihosting 2.0 Keith Packard via
2021-01-07 17:07 ` [PATCH 1/9] semihosting: Move ARM semihosting code to shared directories Keith Packard via
2021-01-07 17:07 ` [PATCH 2/9] semihosting: Change common-semi API to be architecture-independent Keith Packard via
@ 2021-01-07 17:07 ` Keith Packard via
2021-01-07 17:07 ` [PATCH 4/9] semihosting: Support SYS_HEAPINFO when env->boot_info is not set Keith Packard via
` (6 subsequent siblings)
9 siblings, 0 replies; 12+ messages in thread
From: Keith Packard via @ 2021-01-07 17:07 UTC (permalink / raw)
To: qemu-devel
Cc: Peter Maydell, Keith Packard, qemu-riscv, Sagar Karandikar,
Bastian Koppelmann, Laurent Vivier, qemu-arm, Alistair Francis,
Palmer Dabbelt, Alex Bennée
This makes all of the internal interfaces architecture-independent and
renames the internal functions to use the 'common_semi' prefix instead
of 'arm' or 'arm_semi'.
To do this, some new architecture-specific internal helper functions
were created:
static inline target_ulong
common_semi_arg(CPUState *cs, int argno)
Returns the argno'th semihosting argument, where argno can be
either 0 or 1.
static inline void
common_semi_set_ret(CPUState *cs, target_ulong ret)
Sets the semihosting return value.
static inline bool
common_semi_sys_exit_extended(CPUState *cs, int nr)
This detects whether the specified semihosting call, which
is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should
be executed using the TARGET_SYS_EXIT_EXTENDED semantics.
static inline target_ulong
common_semi_rambase(CPUState *cs)
Returns the base of RAM region used for heap and stack. This
is used to construct plausible values for the SYS_HEAPINFO
call.
In addition, several existing functions have been changed to flag
areas of code which are architecture specific:
static target_ulong
common_semi_flen_buf(CPUState *cs)
Returns the current stack pointer minus 64, which is
where a stat structure will be placed on the stack
#define GET_ARG(n)
This fetches arguments from the semihosting command's argument
block. The address of this is available implicitly through the
local 'args' variable. This is *mostly* architecture
independent, but does depend on the current ABI's notion of
the size of a 'long' parameter, which may need run-time checks
(as it does on AARCH64)
#define SET_ARG(n, val)
This mirrors GET_ARG and stores data back into the argument
block.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
----
v2:
Add common_semi_rambase hook to get memory address for
SYS_HEAPINFO call.
Message-Id: <20201214200713.3886611-4-keithp@keithp.com>
---
hw/semihosting/common-semi.c | 351 +++++++++++++++++++----------------
1 file changed, 187 insertions(+), 164 deletions(-)
diff --git a/hw/semihosting/common-semi.c b/hw/semihosting/common-semi.c
index 74f09c038c..33c82f73b1 100644
--- a/hw/semihosting/common-semi.c
+++ b/hw/semihosting/common-semi.c
@@ -32,15 +32,18 @@
#include "cpu.h"
#include "hw/semihosting/semihost.h"
#include "hw/semihosting/console.h"
+#include "hw/semihosting/common-semi.h"
#include "qemu/log.h"
#ifdef CONFIG_USER_ONLY
#include "qemu.h"
-#define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)
+#define COMMON_SEMI_HEAP_SIZE (128 * 1024 * 1024)
#else
#include "exec/gdbstub.h"
#include "qemu/cutils.h"
+#ifdef TARGET_ARM
#include "hw/arm/boot.h"
+#endif
#include "hw/boards.h"
#endif
@@ -134,6 +137,50 @@ typedef struct GuestFD {
static GArray *guestfd_array;
+#ifdef TARGET_ARM
+static inline target_ulong
+common_semi_arg(CPUState *cs, int argno)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ if (is_a64(env)) {
+ return env->xregs[argno];
+ } else {
+ return env->regs[argno];
+ }
+}
+
+static inline void
+common_semi_set_ret(CPUState *cs, target_ulong ret)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ if (is_a64(env)) {
+ env->xregs[0] = ret;
+ } else {
+ env->regs[0] = ret;
+ }
+}
+
+static inline bool
+common_semi_sys_exit_extended(CPUState *cs, int nr)
+{
+ return (nr == TARGET_SYS_EXIT_EXTENDED || is_a64(cs->env_ptr));
+}
+
+#ifndef CONFIG_USER_ONLY
+#include "hw/arm/boot.h"
+static inline target_ulong
+common_semi_rambase(CPUState *cs)
+{
+ CPUArchState *env = cs->env_ptr;
+ const struct arm_boot_info *info = env->boot_info;
+ return info->loader_start;
+}
+#endif
+
+#endif /* TARGET_ARM */
+
/*
* Allocate a new guest file descriptor and return it; if we
* couldn't allocate a new fd then return -1.
@@ -239,11 +286,10 @@ static target_ulong syscall_err;
#include "exec/softmmu-semi.h"
#endif
-static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code)
+static inline uint32_t set_swi_errno(CPUState *cs, 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;
@@ -254,10 +300,9 @@ static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code)
return code;
}
-static inline uint32_t get_swi_errno(CPUARMState *env)
+static inline uint32_t get_swi_errno(CPUState *cs)
{
#ifdef CONFIG_USER_ONLY
- CPUState *cs = env_cpu(env);
TaskState *ts = cs->opaque;
return ts->swi_errno;
@@ -266,24 +311,22 @@ static inline uint32_t get_swi_errno(CPUARMState *env)
#endif
}
-static target_ulong arm_semi_syscall_len;
+static target_ulong common_semi_syscall_len;
-static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
+static void common_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
{
- ARMCPU *cpu = ARM_CPU(cs);
- CPUARMState *env = &cpu->env;
- target_ulong reg0 = is_a64(env) ? env->xregs[0] : env->regs[0];
+ target_ulong reg0 = common_semi_arg(cs, 0);
if (ret == (target_ulong)-1) {
errno = err;
- set_swi_errno(env, -1);
+ set_swi_errno(cs, -1);
reg0 = ret;
} else {
/* Fixup syscalls that use nonstardard return conventions. */
switch (reg0) {
case TARGET_SYS_WRITE:
case TARGET_SYS_READ:
- reg0 = arm_semi_syscall_len - ret;
+ reg0 = common_semi_syscall_len - ret;
break;
case TARGET_SYS_SEEK:
reg0 = 0;
@@ -293,77 +336,66 @@ static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
break;
}
}
- if (is_a64(env)) {
- env->xregs[0] = reg0;
- } else {
- env->regs[0] = reg0;
- }
+ common_semi_set_ret(cs, reg0);
}
-static target_ulong arm_flen_buf(ARMCPU *cpu)
+static target_ulong common_semi_flen_buf(CPUState *cs)
{
+ target_ulong sp;
+#ifdef TARGET_ARM
/* 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.
*/
+ ARMCPU *cpu = ARM_CPU(cs);
CPUARMState *env = &cpu->env;
- target_ulong sp;
if (is_a64(env)) {
sp = env->xregs[31];
} else {
sp = env->regs[13];
}
+#endif
return sp - 64;
}
-static void arm_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err)
+static void
+common_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err)
{
- ARMCPU *cpu = ARM_CPU(cs);
- CPUARMState *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, arm_flen_buf(cpu) + 32, (uint8_t *)&size, 4, 0);
+ cpu_memory_rw_debug(cs, common_semi_flen_buf(cs) + 32,
+ (uint8_t *)&size, 4, 0);
size = be32_to_cpu(size);
- if (is_a64(env)) {
- env->xregs[0] = size;
- } else {
- env->regs[0] = size;
- }
+ common_semi_set_ret(cs, size);
errno = err;
- set_swi_errno(env, -1);
+ set_swi_errno(cs, -1);
}
-static int arm_semi_open_guestfd;
+static int common_semi_open_guestfd;
-static void arm_semi_open_cb(CPUState *cs, target_ulong ret, target_ulong err)
+static void
+common_semi_open_cb(CPUState *cs, target_ulong ret, target_ulong err)
{
- ARMCPU *cpu = ARM_CPU(cs);
- CPUARMState *env = &cpu->env;
if (ret == (target_ulong)-1) {
errno = err;
- set_swi_errno(env, -1);
- dealloc_guestfd(arm_semi_open_guestfd);
+ set_swi_errno(cs, -1);
+ dealloc_guestfd(common_semi_open_guestfd);
} else {
- associate_guestfd(arm_semi_open_guestfd, ret);
- ret = arm_semi_open_guestfd;
- }
-
- if (is_a64(env)) {
- env->xregs[0] = ret;
- } else {
- env->regs[0] = ret;
+ associate_guestfd(common_semi_open_guestfd, ret);
+ ret = common_semi_open_guestfd;
}
+ common_semi_set_ret(cs, ret);
}
-static target_ulong arm_gdb_syscall(ARMCPU *cpu, gdb_syscall_complete_cb cb,
- const char *fmt, ...)
+static target_ulong
+common_semi_gdb_syscall(CPUState *cs, gdb_syscall_complete_cb cb,
+ const char *fmt, ...)
{
va_list va;
- CPUARMState *env = &cpu->env;
va_start(va, fmt);
gdb_do_syscallv(cb, fmt, va);
@@ -386,7 +418,7 @@ static target_ulong arm_gdb_syscall(ARMCPU *cpu, gdb_syscall_complete_cb cb,
* doing something with the return value is not possible to make.
*/
- return is_a64(env) ? env->xregs[0] : env->regs[0];
+ return common_semi_arg(cs, 0);
}
/*
@@ -395,20 +427,18 @@ static target_ulong arm_gdb_syscall(ARMCPU *cpu, gdb_syscall_complete_cb cb,
* do the work and return the required return value for the guest,
* setting the guest errno if appropriate.
*/
-typedef uint32_t sys_closefn(ARMCPU *cpu, GuestFD *gf);
-typedef uint32_t sys_writefn(ARMCPU *cpu, GuestFD *gf,
+typedef uint32_t sys_closefn(CPUState *cs, GuestFD *gf);
+typedef uint32_t sys_writefn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len);
-typedef uint32_t sys_readfn(ARMCPU *cpu, GuestFD *gf,
+typedef uint32_t sys_readfn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len);
-typedef uint32_t sys_isattyfn(ARMCPU *cpu, GuestFD *gf);
-typedef uint32_t sys_seekfn(ARMCPU *cpu, GuestFD *gf,
+typedef uint32_t sys_isattyfn(CPUState *cs, GuestFD *gf);
+typedef uint32_t sys_seekfn(CPUState *cs, GuestFD *gf,
target_ulong offset);
-typedef uint32_t sys_flenfn(ARMCPU *cpu, GuestFD *gf);
+typedef uint32_t sys_flenfn(CPUState *cs, GuestFD *gf);
-static uint32_t host_closefn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t host_closefn(CPUState *cs, GuestFD *gf)
{
- CPUARMState *env = &cpu->env;
-
/*
* Only close the underlying host fd if it's one we opened on behalf
* of the guest in SYS_OPEN.
@@ -418,20 +448,21 @@ static uint32_t host_closefn(ARMCPU *cpu, GuestFD *gf)
gf->hostfd == STDERR_FILENO) {
return 0;
}
- return set_swi_errno(env, close(gf->hostfd));
+ return set_swi_errno(cs, close(gf->hostfd));
}
-static uint32_t host_writefn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t host_writefn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
+ CPUArchState *env = cs->env_ptr;
uint32_t ret;
- CPUARMState *env = &cpu->env;
char *s = lock_user(VERIFY_READ, buf, len, 1);
+ (void) env; /* Used in arm softmmu lock_user implicitly */
if (!s) {
/* Return bytes not written on error */
return len;
}
- ret = set_swi_errno(env, write(gf->hostfd, s, len));
+ ret = set_swi_errno(cs, write(gf->hostfd, s, len));
unlock_user(s, buf, 0);
if (ret == (uint32_t)-1) {
ret = 0;
@@ -440,18 +471,19 @@ static uint32_t host_writefn(ARMCPU *cpu, GuestFD *gf,
return len - ret;
}
-static uint32_t host_readfn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t host_readfn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
+ CPUArchState *env = cs->env_ptr;
uint32_t ret;
- CPUARMState *env = &cpu->env;
char *s = lock_user(VERIFY_WRITE, buf, len, 0);
+ (void) env; /* Used in arm softmmu lock_user implicitly */
if (!s) {
/* return bytes not read */
return len;
}
do {
- ret = set_swi_errno(env, read(gf->hostfd, s, len));
+ ret = set_swi_errno(cs, read(gf->hostfd, s, len));
} while (ret == -1 && errno == EINTR);
unlock_user(s, buf, len);
if (ret == (uint32_t)-1) {
@@ -461,68 +493,66 @@ static uint32_t host_readfn(ARMCPU *cpu, GuestFD *gf,
return len - ret;
}
-static uint32_t host_isattyfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t host_isattyfn(CPUState *cs, GuestFD *gf)
{
return isatty(gf->hostfd);
}
-static uint32_t host_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
+static uint32_t host_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset)
{
- CPUARMState *env = &cpu->env;
- uint32_t ret = set_swi_errno(env, lseek(gf->hostfd, offset, SEEK_SET));
+ uint32_t ret = set_swi_errno(cs, lseek(gf->hostfd, offset, SEEK_SET));
if (ret == (uint32_t)-1) {
return -1;
}
return 0;
}
-static uint32_t host_flenfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t host_flenfn(CPUState *cs, GuestFD *gf)
{
- CPUARMState *env = &cpu->env;
struct stat buf;
- uint32_t ret = set_swi_errno(env, fstat(gf->hostfd, &buf));
+ uint32_t ret = set_swi_errno(cs, fstat(gf->hostfd, &buf));
if (ret == (uint32_t)-1) {
return -1;
}
return buf.st_size;
}
-static uint32_t gdb_closefn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t gdb_closefn(CPUState *cs, GuestFD *gf)
{
- return arm_gdb_syscall(cpu, arm_semi_cb, "close,%x", gf->hostfd);
+ return common_semi_gdb_syscall(cs, common_semi_cb, "close,%x", gf->hostfd);
}
-static uint32_t gdb_writefn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t gdb_writefn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
- arm_semi_syscall_len = len;
- return arm_gdb_syscall(cpu, arm_semi_cb, "write,%x,%x,%x",
- gf->hostfd, buf, len);
+ common_semi_syscall_len = len;
+ return common_semi_gdb_syscall(cs, common_semi_cb, "write,%x,%x,%x",
+ gf->hostfd, buf, len);
}
-static uint32_t gdb_readfn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t gdb_readfn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
- arm_semi_syscall_len = len;
- return arm_gdb_syscall(cpu, arm_semi_cb, "read,%x,%x,%x",
- gf->hostfd, buf, len);
+ common_semi_syscall_len = len;
+ return common_semi_gdb_syscall(cs, common_semi_cb, "read,%x,%x,%x",
+ gf->hostfd, buf, len);
}
-static uint32_t gdb_isattyfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t gdb_isattyfn(CPUState *cs, GuestFD *gf)
{
- return arm_gdb_syscall(cpu, arm_semi_cb, "isatty,%x", gf->hostfd);
+ return common_semi_gdb_syscall(cs, common_semi_cb, "isatty,%x", gf->hostfd);
}
-static uint32_t gdb_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
+static uint32_t gdb_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset)
{
- return arm_gdb_syscall(cpu, arm_semi_cb, "lseek,%x,%x,0",
- gf->hostfd, offset);
+ return common_semi_gdb_syscall(cs, common_semi_cb, "lseek,%x,%x,0",
+ gf->hostfd, offset);
}
-static uint32_t gdb_flenfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t gdb_flenfn(CPUState *cs, GuestFD *gf)
{
- return arm_gdb_syscall(cpu, arm_semi_flen_cb, "fstat,%x,%x",
- gf->hostfd, arm_flen_buf(cpu));
+ return common_semi_gdb_syscall(cs, common_semi_flen_cb, "fstat,%x,%x",
+ gf->hostfd, common_semi_flen_buf(cs));
}
#define SHFB_MAGIC_0 0x53
@@ -551,31 +581,29 @@ static void init_featurefile_guestfd(int guestfd)
gf->featurefile_offset = 0;
}
-static uint32_t featurefile_closefn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t featurefile_closefn(CPUState *cs, GuestFD *gf)
{
/* Nothing to do */
return 0;
}
-static uint32_t featurefile_writefn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t featurefile_writefn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
/* This fd can never be open for writing */
- CPUARMState *env = &cpu->env;
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
-static uint32_t featurefile_readfn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t featurefile_readfn(CPUState *cs, GuestFD *gf,
target_ulong buf, uint32_t len)
{
+ CPUArchState *env = cs->env_ptr;
uint32_t i;
-#ifndef CONFIG_USER_ONLY
- CPUARMState *env = &cpu->env;
-#endif
char *s;
+ (void) env; /* Used in arm softmmu lock_user implicitly */
s = lock_user(VERIFY_WRITE, buf, len, 0);
if (!s) {
return len;
@@ -595,19 +623,19 @@ static uint32_t featurefile_readfn(ARMCPU *cpu, GuestFD *gf,
return len - i;
}
-static uint32_t featurefile_isattyfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t featurefile_isattyfn(CPUState *cs, GuestFD *gf)
{
return 0;
}
-static uint32_t featurefile_seekfn(ARMCPU *cpu, GuestFD *gf,
+static uint32_t featurefile_seekfn(CPUState *cs, GuestFD *gf,
target_ulong offset)
{
gf->featurefile_offset = offset;
return 0;
}
-static uint32_t featurefile_flenfn(ARMCPU *cpu, GuestFD *gf)
+static uint32_t featurefile_flenfn(CPUState *cs, GuestFD *gf)
{
return sizeof(featurefile_data);
}
@@ -651,16 +679,17 @@ static const GuestFDFunctions guestfd_fns[] = {
/* Read the input value from the argument block; fail the semihosting
* call if the memory read fails.
*/
+#ifdef TARGET_ARM
#define GET_ARG(n) do { \
if (is_a64(env)) { \
if (get_user_u64(arg ## n, args + (n) * 8)) { \
errno = EFAULT; \
- return set_swi_errno(env, -1); \
+ return set_swi_errno(cs, -1); \
} \
} else { \
if (get_user_u32(arg ## n, args + (n) * 4)) { \
errno = EFAULT; \
- return set_swi_errno(env, -1); \
+ return set_swi_errno(cs, -1); \
} \
} \
} while (0)
@@ -669,6 +698,7 @@ static const GuestFDFunctions guestfd_fns[] = {
(is_a64(env) ? \
put_user_u64(val, args + (n) * 8) : \
put_user_u32(val, args + (n) * 4))
+#endif
/*
* Do a semihosting call.
@@ -681,8 +711,7 @@ static const GuestFDFunctions guestfd_fns[] = {
*/
target_ulong do_common_semihosting(CPUState *cs)
{
- ARMCPU *cpu = ARM_CPU(cs);
- CPUARMState *env = &cpu->env;
+ CPUArchState *env = cs->env_ptr;
target_ulong args;
target_ulong arg0, arg1, arg2, arg3;
char * s;
@@ -691,14 +720,9 @@ target_ulong do_common_semihosting(CPUState *cs)
uint32_t len;
GuestFD *gf;
- if (is_a64(env)) {
- /* Note that the syscall number is in W0, not X0 */
- nr = env->xregs[0] & 0xffffffffU;
- args = env->xregs[1];
- } else {
- nr = env->regs[0];
- args = env->regs[1];
- }
+ (void) env; /* Used implicitly by arm lock_user macro */
+ nr = common_semi_arg(cs, 0) & 0xffffffffU;
+ args = common_semi_arg(cs, 1);
switch (nr) {
case TARGET_SYS_OPEN:
@@ -711,19 +735,19 @@ target_ulong do_common_semihosting(CPUState *cs)
s = lock_user_string(arg0);
if (!s) {
errno = EFAULT;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
if (arg1 >= 12) {
unlock_user(s, arg0, 0);
errno = EINVAL;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
guestfd = alloc_guestfd();
if (guestfd < 0) {
unlock_user(s, arg0, 0);
errno = EMFILE;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
if (strcmp(s, ":tt") == 0) {
@@ -752,18 +776,19 @@ target_ulong do_common_semihosting(CPUState *cs)
if (arg1 != 0 && arg1 != 1) {
dealloc_guestfd(guestfd);
errno = EACCES;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
init_featurefile_guestfd(guestfd);
return guestfd;
}
if (use_gdb_syscalls()) {
- arm_semi_open_guestfd = guestfd;
- ret = arm_gdb_syscall(cpu, arm_semi_open_cb, "open,%s,%x,1a4", arg0,
- (int)arg2 + 1, gdb_open_modeflags[arg1]);
+ common_semi_open_guestfd = guestfd;
+ ret = common_semi_gdb_syscall(cs, common_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));
+ ret = set_swi_errno(cs, open(s, open_modeflags[arg1], 0644));
if (ret == (uint32_t)-1) {
dealloc_guestfd(guestfd);
} else {
@@ -780,17 +805,17 @@ target_ulong do_common_semihosting(CPUState *cs)
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- ret = guestfd_fns[gf->type].closefn(cpu, gf);
+ ret = guestfd_fns[gf->type].closefn(cs, gf);
dealloc_guestfd(arg0);
return ret;
case TARGET_SYS_WRITEC:
- qemu_semihosting_console_outc(env, args);
+ qemu_semihosting_console_outc(cs->env_ptr, args);
return 0xdeadbeef;
case TARGET_SYS_WRITE0:
- return qemu_semihosting_console_outs(env, args);
+ return qemu_semihosting_console_outs(cs->env_ptr, args);
case TARGET_SYS_WRITE:
GET_ARG(0);
GET_ARG(1);
@@ -800,10 +825,10 @@ target_ulong do_common_semihosting(CPUState *cs)
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- return guestfd_fns[gf->type].writefn(cpu, gf, arg1, len);
+ return guestfd_fns[gf->type].writefn(cs, gf, arg1, len);
case TARGET_SYS_READ:
GET_ARG(0);
GET_ARG(1);
@@ -813,22 +838,22 @@ target_ulong do_common_semihosting(CPUState *cs)
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- return guestfd_fns[gf->type].readfn(cpu, gf, arg1, len);
+ return guestfd_fns[gf->type].readfn(cs, gf, arg1, len);
case TARGET_SYS_READC:
- return qemu_semihosting_console_inc(env);
+ return qemu_semihosting_console_inc(cs->env_ptr);
case TARGET_SYS_ISTTY:
GET_ARG(0);
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- return guestfd_fns[gf->type].isattyfn(cpu, gf);
+ return guestfd_fns[gf->type].isattyfn(cs, gf);
case TARGET_SYS_SEEK:
GET_ARG(0);
GET_ARG(1);
@@ -836,20 +861,20 @@ target_ulong do_common_semihosting(CPUState *cs)
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- return guestfd_fns[gf->type].seekfn(cpu, gf, arg1);
+ return guestfd_fns[gf->type].seekfn(cs, gf, arg1);
case TARGET_SYS_FLEN:
GET_ARG(0);
gf = get_guestfd(arg0);
if (!gf) {
errno = EBADF;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- return guestfd_fns[gf->type].flenfn(cpu, gf);
+ return guestfd_fns[gf->type].flenfn(cs, gf);
case TARGET_SYS_TMPNAM:
qemu_log_mask(LOG_UNIMP, "%s: SYS_TMPNAM not implemented", __func__);
return -1;
@@ -857,15 +882,15 @@ target_ulong do_common_semihosting(CPUState *cs)
GET_ARG(0);
GET_ARG(1);
if (use_gdb_syscalls()) {
- ret = arm_gdb_syscall(cpu, arm_semi_cb, "unlink,%s",
- arg0, (int)arg1 + 1);
+ ret = common_semi_gdb_syscall(cs, common_semi_cb, "unlink,%s",
+ arg0, (int)arg1 + 1);
} else {
s = lock_user_string(arg0);
if (!s) {
errno = EFAULT;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- ret = set_swi_errno(env, remove(s));
+ ret = set_swi_errno(cs, remove(s));
unlock_user(s, arg0, 0);
}
return ret;
@@ -875,17 +900,18 @@ target_ulong do_common_semihosting(CPUState *cs)
GET_ARG(2);
GET_ARG(3);
if (use_gdb_syscalls()) {
- return arm_gdb_syscall(cpu, arm_semi_cb, "rename,%s,%s",
- arg0, (int)arg1 + 1, arg2, (int)arg3 + 1);
+ return common_semi_gdb_syscall(cs, common_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);
+ ret = set_swi_errno(cs, -1);
} else {
- ret = set_swi_errno(env, rename(s, s2));
+ ret = set_swi_errno(cs, rename(s, s2));
}
if (s2)
unlock_user(s2, arg2, 0);
@@ -896,25 +922,25 @@ target_ulong do_common_semihosting(CPUState *cs)
case TARGET_SYS_CLOCK:
return clock() / (CLOCKS_PER_SEC / 100);
case TARGET_SYS_TIME:
- return set_swi_errno(env, time(NULL));
+ return set_swi_errno(cs, time(NULL));
case TARGET_SYS_SYSTEM:
GET_ARG(0);
GET_ARG(1);
if (use_gdb_syscalls()) {
- return arm_gdb_syscall(cpu, arm_semi_cb, "system,%s",
- arg0, (int)arg1 + 1);
+ return common_semi_gdb_syscall(cs, common_semi_cb, "system,%s",
+ arg0, (int)arg1 + 1);
} else {
s = lock_user_string(arg0);
if (!s) {
errno = EFAULT;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
- ret = set_swi_errno(env, system(s));
+ ret = set_swi_errno(cs, system(s));
unlock_user(s, arg0, 0);
return ret;
}
case TARGET_SYS_ERRNO:
- return get_swi_errno(env);
+ return get_swi_errno(cs);
case TARGET_SYS_GET_CMDLINE:
{
/* Build a command-line from the original argv.
@@ -966,21 +992,21 @@ target_ulong do_common_semihosting(CPUState *cs)
if (output_size > input_size) {
/* Not enough space to store command-line arguments. */
errno = E2BIG;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -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);
+ return set_swi_errno(cs, -1);
}
/* Lock the buffer on the ARM side. */
output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
if (!output_buffer) {
errno = EFAULT;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
/* Copy the command-line arguments. */
@@ -996,7 +1022,7 @@ target_ulong do_common_semihosting(CPUState *cs)
if (copy_from_user(output_buffer, ts->info->arg_start,
output_size)) {
errno = EFAULT;
- status = set_swi_errno(env, -1);
+ status = set_swi_errno(cs, -1);
goto out;
}
@@ -1021,8 +1047,7 @@ target_ulong do_common_semihosting(CPUState *cs)
#ifdef CONFIG_USER_ONLY
TaskState *ts = cs->opaque;
#else
- const struct arm_boot_info *info = env->boot_info;
- target_ulong rambase = info->loader_start;
+ target_ulong rambase = common_semi_rambase(cs);
#endif
GET_ARG(0);
@@ -1036,7 +1061,7 @@ target_ulong do_common_semihosting(CPUState *cs)
abi_ulong ret;
ts->heap_base = do_brk(0);
- limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
+ limit = ts->heap_base + COMMON_SEMI_HEAP_SIZE;
/* Try a big heap, and reduce the size if that fails. */
for (;;) {
ret = do_brk(limit);
@@ -1064,23 +1089,19 @@ target_ulong do_common_semihosting(CPUState *cs)
for (i = 0; i < ARRAY_SIZE(retvals); i++) {
bool fail;
- if (is_a64(env)) {
- fail = put_user_u64(retvals[i], arg0 + i * 8);
- } else {
- fail = put_user_u32(retvals[i], arg0 + i * 4);
- }
+ fail = SET_ARG(i, retvals[i]);
if (fail) {
/* Couldn't write back to argument block */
errno = EFAULT;
- return set_swi_errno(env, -1);
+ return set_swi_errno(cs, -1);
}
}
return 0;
}
case TARGET_SYS_EXIT:
case TARGET_SYS_EXIT_EXTENDED:
- if (nr == TARGET_SYS_EXIT_EXTENDED || is_a64(env)) {
+ if (common_semi_sys_exit_extended(cs, nr)) {
/*
* The A64 version of SYS_EXIT takes a parameter block,
* so the application-exit type can return a subcode which
@@ -1105,7 +1126,7 @@ target_ulong do_common_semihosting(CPUState *cs)
*/
ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
}
- gdb_exit(env, ret);
+ gdb_exit(cs->env_ptr, ret);
exit(ret);
case TARGET_SYS_SYNCCACHE:
/*
@@ -1113,9 +1134,11 @@ target_ulong do_common_semihosting(CPUState *cs)
* virtual address range. This is a nop for us since we don't
* implement caches. This is only present on A64.
*/
- if (is_a64(env)) {
+#ifdef TARGET_ARM
+ if (is_a64(cs->env_ptr)) {
return 0;
}
+#endif
/* fall through -- invalid for A32/T32 */
default:
fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
--
2.29.2
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 5/9] riscv: Add semihosting support
2021-01-07 17:07 [PATCH 0/9] Add RISC-V semihosting 0.2. Finish ARM semihosting 2.0 Keith Packard via
` (3 preceding siblings ...)
2021-01-07 17:07 ` [PATCH 4/9] semihosting: Support SYS_HEAPINFO when env->boot_info is not set Keith Packard via
@ 2021-01-07 17:07 ` Keith Packard via
2021-01-07 17:07 ` [PATCH 6/9] riscv: Add semihosting support for user mode Keith Packard via
` (4 subsequent siblings)
9 siblings, 0 replies; 12+ messages in thread
From: Keith Packard via @ 2021-01-07 17:07 UTC (permalink / raw)
To: qemu-devel
Cc: Peter Maydell, Keith Packard, qemu-riscv, Sagar Karandikar,
Bastian Koppelmann, Laurent Vivier, qemu-arm, Alistair Francis,
Palmer Dabbelt, Alex Bennée
Adapt the arm semihosting support code for RISCV. This implementation
is based on the standard for RISC-V semihosting version 0.2 as
documented in
https://github.com/riscv/riscv-semihosting-spec/releases/tag/0.2
Signed-off-by: Keith Packard <keithp@keithp.com>
Message-Id: <20201214200713.3886611-6-keithp@keithp.com>
---
default-configs/devices/riscv32-softmmu.mak | 2 +
default-configs/devices/riscv64-softmmu.mak | 2 +
.../targets/riscv32-linux-user.mak | 1 +
.../targets/riscv64-linux-user.mak | 1 +
hw/semihosting/common-semi.c | 82 ++++++++++++++++++-
hw/semihosting/common-semi.h | 5 +-
linux-user/qemu.h | 4 +-
linux-user/semihost.c | 8 +-
qemu-options.hx | 10 ++-
target/riscv/cpu_bits.h | 1 +
target/riscv/cpu_helper.c | 10 +++
.../riscv/insn_trans/trans_privileged.c.inc | 37 ++++++++-
target/riscv/translate.c | 11 +++
13 files changed, 162 insertions(+), 12 deletions(-)
diff --git a/default-configs/devices/riscv32-softmmu.mak b/default-configs/devices/riscv32-softmmu.mak
index 94a236c9c2..d847bd5692 100644
--- a/default-configs/devices/riscv32-softmmu.mak
+++ b/default-configs/devices/riscv32-softmmu.mak
@@ -3,6 +3,8 @@
# Uncomment the following lines to disable these optional devices:
#
#CONFIG_PCI_DEVICES=n
+CONFIG_SEMIHOSTING=y
+CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
# Boards:
#
diff --git a/default-configs/devices/riscv64-softmmu.mak b/default-configs/devices/riscv64-softmmu.mak
index 76b6195648..d5eec75f05 100644
--- a/default-configs/devices/riscv64-softmmu.mak
+++ b/default-configs/devices/riscv64-softmmu.mak
@@ -3,6 +3,8 @@
# Uncomment the following lines to disable these optional devices:
#
#CONFIG_PCI_DEVICES=n
+CONFIG_SEMIHOSTING=y
+CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
# Boards:
#
diff --git a/default-configs/targets/riscv32-linux-user.mak b/default-configs/targets/riscv32-linux-user.mak
index dfb259e8aa..6a9d1b1bc1 100644
--- a/default-configs/targets/riscv32-linux-user.mak
+++ b/default-configs/targets/riscv32-linux-user.mak
@@ -2,3 +2,4 @@ TARGET_ARCH=riscv32
TARGET_BASE_ARCH=riscv
TARGET_ABI_DIR=riscv
TARGET_XML_FILES= gdb-xml/riscv-32bit-cpu.xml gdb-xml/riscv-32bit-fpu.xml gdb-xml/riscv-64bit-fpu.xml gdb-xml/riscv-32bit-csr.xml gdb-xml/riscv-32bit-virtual.xml
+CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
diff --git a/default-configs/targets/riscv64-linux-user.mak b/default-configs/targets/riscv64-linux-user.mak
index b13895f3b0..0a92849a1b 100644
--- a/default-configs/targets/riscv64-linux-user.mak
+++ b/default-configs/targets/riscv64-linux-user.mak
@@ -2,3 +2,4 @@ TARGET_ARCH=riscv64
TARGET_BASE_ARCH=riscv
TARGET_ABI_DIR=riscv
TARGET_XML_FILES= gdb-xml/riscv-64bit-cpu.xml gdb-xml/riscv-32bit-fpu.xml gdb-xml/riscv-64bit-fpu.xml gdb-xml/riscv-64bit-csr.xml gdb-xml/riscv-64bit-virtual.xml
+CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
diff --git a/hw/semihosting/common-semi.c b/hw/semihosting/common-semi.c
index f09deff4d3..f0cf5f10f5 100644
--- a/hw/semihosting/common-semi.c
+++ b/hw/semihosting/common-semi.c
@@ -1,6 +1,6 @@
/*
* Semihosting support for systems modeled on the Arm "Angel"
- * semihosting syscalls design.
+ * semihosting syscalls design. This includes Arm and RISC-V processors
*
* Copyright (c) 2005, 2007 CodeSourcery.
* Copyright (c) 2019 Linaro
@@ -25,6 +25,10 @@
* ARM Semihosting is documented in:
* Semihosting for AArch32 and AArch64 Release 2.0
* https://static.docs.arm.com/100863/0200/semihosting.pdf
+ *
+ * RISC-V Semihosting is documented in:
+ * RISC-V Semihosting
+ * https://github.com/riscv/riscv-semihosting-spec/blob/main/riscv-semihosting-spec.adoc
*/
#include "qemu/osdep.h"
@@ -222,6 +226,42 @@ common_semi_rambase(CPUState *cs)
#endif /* TARGET_ARM */
+#ifdef TARGET_RISCV
+static inline target_ulong
+common_semi_arg(CPUState *cs, int argno)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ return env->gpr[xA0 + argno];
+}
+
+static inline void
+common_semi_set_ret(CPUState *cs, target_ulong ret)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ env->gpr[xA0] = ret;
+}
+
+static inline bool
+common_semi_sys_exit_extended(CPUState *cs, int nr)
+{
+ return (nr == TARGET_SYS_EXIT_EXTENDED || sizeof(target_ulong) == 8);
+}
+
+#ifndef CONFIG_USER_ONLY
+
+static inline target_ulong
+common_semi_rambase(CPUState *cs)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ return common_semi_find_region_base(env->gpr[xSP]);
+}
+#endif
+
+#endif
+
/*
* Allocate a new guest file descriptor and return it; if we
* couldn't allocate a new fd then return -1.
@@ -398,6 +438,12 @@ static target_ulong common_semi_flen_buf(CPUState *cs)
sp = env->regs[13];
}
#endif
+#ifdef TARGET_RISCV
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+
+ sp = env->gpr[xSP];
+#endif
return sp - 64;
}
@@ -741,6 +787,37 @@ static const GuestFDFunctions guestfd_fns[] = {
put_user_u32(val, args + (n) * 4))
#endif
+#ifdef TARGET_RISCV
+
+/*
+ * get_user_ual is defined as get_user_u32 in softmmu-semi.h,
+ * we need a macro that fetches a target_ulong
+ */
+#define get_user_utl(arg, p) \
+ ((sizeof(target_ulong) == 8) ? \
+ get_user_u64(arg, p) : \
+ get_user_u32(arg, p))
+
+/*
+ * put_user_ual is defined as put_user_u32 in softmmu-semi.h,
+ * we need a macro that stores a target_ulong
+ */
+#define put_user_utl(arg, p) \
+ ((sizeof(target_ulong) == 8) ? \
+ put_user_u64(arg, p) : \
+ put_user_u32(arg, p))
+
+#define GET_ARG(n) do { \
+ if (get_user_utl(arg ## n, args + (n) * sizeof(target_ulong))) { \
+ errno = EFAULT; \
+ return set_swi_errno(cs, -1); \
+ } \
+ } while (0)
+
+#define SET_ARG(n, val) \
+ put_user_utl(val, args + (n) * sizeof(target_ulong))
+#endif
+
/*
* Do a semihosting call.
*
@@ -1179,6 +1256,9 @@ target_ulong do_common_semihosting(CPUState *cs)
if (is_a64(cs->env_ptr)) {
return 0;
}
+#endif
+#ifdef TARGET_RISCV
+ return 0;
#endif
/* fall through -- invalid for A32/T32 */
default:
diff --git a/hw/semihosting/common-semi.h b/hw/semihosting/common-semi.h
index bc53e92c79..0bfab1c669 100644
--- a/hw/semihosting/common-semi.h
+++ b/hw/semihosting/common-semi.h
@@ -1,6 +1,6 @@
/*
* Semihosting support for systems modeled on the Arm "Angel"
- * semihosting syscalls design.
+ * semihosting syscalls design. This includes Arm and RISC-V processors
*
* Copyright (c) 2005, 2007 CodeSourcery.
* Copyright (c) 2019 Linaro
@@ -26,6 +26,9 @@
* Semihosting for AArch32 and AArch64 Release 2.0
* https://static.docs.arm.com/100863/0200/semihosting.pdf
*
+ * RISC-V Semihosting is documented in:
+ * RISC-V Semihosting
+ * https://github.com/riscv/riscv-semihosting-spec/blob/main/riscv-semihosting-spec.adoc
*/
#ifndef COMMON_SEMI_H
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index 534753ca12..17aa992165 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -109,6 +109,8 @@ 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)
@@ -122,7 +124,7 @@ typedef struct TaskState {
#ifdef TARGET_M68K
abi_ulong tp_value;
#endif
-#if defined(TARGET_ARM) || defined(TARGET_M68K)
+#if defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_RISCV)
/* Extra fields for semihosted binaries. */
abi_ulong heap_base;
abi_ulong heap_limit;
diff --git a/linux-user/semihost.c b/linux-user/semihost.c
index a1f0f6050e..c0015ee7f6 100644
--- a/linux-user/semihost.c
+++ b/linux-user/semihost.c
@@ -1,11 +1,11 @@
/*
- * ARM Semihosting Console Support
+ * ARM Compatible Semihosting Console Support.
*
* Copyright (c) 2019 Linaro Ltd
*
- * Currently ARM is unique in having support for semihosting support
- * in linux-user. So for now we implement the common console API but
- * just for arm linux-user.
+ * Currently ARM and RISC-V are unique in having support for
+ * semihosting support in linux-user. So for now we implement the
+ * common console API but just for arm and risc-v linux-user.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
diff --git a/qemu-options.hx b/qemu-options.hx
index 459c916d3d..cc6c3af936 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -4190,10 +4190,10 @@ ERST
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)
SRST
``-semihosting``
- Enable semihosting mode (ARM, M68K, Xtensa, MIPS, Nios II only).
+ Enable semihosting mode (ARM, M68K, Xtensa, MIPS, Nios II, RISC-V only).
Note that this allows guest direct access to the host filesystem, so
should only be used with a trusted guest OS.
@@ -4205,10 +4205,10 @@ 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)
SRST
``-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]``
- Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II
+ Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II, RISC-V
only).
Note that this allows guest direct access to the host filesystem, so
@@ -4223,6 +4223,8 @@ SRST
open/read/write/seek/select. Tensilica baremetal libc for ISS and
linux platform "sim" use this interface.
+ On RISC-V this implements the standard semihosting API, version 0.2.
+
``target=native|gdb|auto``
Defines where the semihosting calls will be addressed, to QEMU
(``native``) or to GDB (``gdb``). The default is ``auto``, which
diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index b41e8836c3..4196ef8b69 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -542,6 +542,7 @@
#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_INST_GUEST_PAGE_FAULT 0x14
#define RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT 0x15
#define RISCV_EXCP_VIRT_INSTRUCTION_FAULT 0x16
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index a2afb95fa1..f8350f5f78 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -24,6 +24,7 @@
#include "exec/exec-all.h"
#include "tcg/tcg-op.h"
#include "trace.h"
+#include "hw/semihosting/common-semi.h"
int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch)
{
@@ -847,6 +848,15 @@ void riscv_cpu_do_interrupt(CPUState *cs)
target_ulong htval = 0;
target_ulong mtval2 = 0;
+ if (cause == RISCV_EXCP_SEMIHOST) {
+ if (env->priv >= PRV_S) {
+ env->gpr[xA0] = do_common_semihosting(cs);
+ 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.c.inc b/target/riscv/insn_trans/trans_privileged.c.inc
index 2a61a853bf..32312be202 100644
--- a/target/riscv/insn_trans/trans_privileged.c.inc
+++ b/target/riscv/insn_trans/trans_privileged.c.inc
@@ -29,7 +29,42 @@ static bool trans_ecall(DisasContext *ctx, arg_ecall *a)
static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a)
{
- generate_exception(ctx, RISCV_EXCP_BREAKPOINT);
+ target_ulong ebreak_addr = ctx->base.pc_next;
+ target_ulong pre_addr = ebreak_addr - 4;
+ target_ulong post_addr = ebreak_addr + 4;
+ uint32_t pre = 0;
+ uint32_t ebreak = 0;
+ uint32_t post = 0;
+
+ /*
+ * 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 required so that the sequence is easy
+ * to validate.
+ *
+ * The three instructions are required to lie in the same page so
+ * that no exception will be raised when fetching them.
+ */
+
+ if ((pre_addr & TARGET_PAGE_MASK) == (post_addr & TARGET_PAGE_MASK)) {
+ pre = opcode_at(&ctx->base, pre_addr);
+ ebreak = opcode_at(&ctx->base, ebreak_addr);
+ post = opcode_at(&ctx->base, post_addr);
+ }
+
+ 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/translate.c b/target/riscv/translate.c
index 554d52a4be..0f28b5f41e 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -64,6 +64,7 @@ typedef struct DisasContext {
uint16_t vlen;
uint16_t mlen;
bool vl_eq_vlmax;
+ CPUState *cs;
} DisasContext;
#ifdef TARGET_RISCV64
@@ -747,6 +748,15 @@ 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.c.inc"
#include "insn_trans/trans_rvm.c.inc"
@@ -814,6 +824,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
ctx->lmul = FIELD_EX32(tb_flags, TB_FLAGS, LMUL);
ctx->mlen = 1 << (ctx->sew + 3 - ctx->lmul);
ctx->vl_eq_vlmax = FIELD_EX32(tb_flags, TB_FLAGS, VL_EQ_VLMAX);
+ ctx->cs = cs;
}
static void riscv_tr_tb_start(DisasContextBase *db, CPUState *cpu)
--
2.29.2
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