| Message ID | 20230721094720.902454-2-thuth@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | riscv: Fix the console of the Spike machine on big endian hosts | expand |
On Fri, Jul 21, 2023 at 5:48 PM Thomas Huth <thuth@redhat.com> wrote: > > The character that should be printed is stored in the 64 bit "payload" > variable. The code currently tries to print it by taking the address > of the variable and passing this pointer to qemu_chr_fe_write(). However, > this only works on little endian hosts where the least significant bits > are stored on the lowest address. To do this in a portable way, we have > to store the value in an uint8_t variable instead. > > Fixes: 5033606780 ("RISC-V HTIF Console") > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- > hw/char/riscv_htif.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > Reviewed-by: Bin Meng <bmeng@tinylab.org>
On 7/21/23 06:47, Thomas Huth wrote: > The character that should be printed is stored in the 64 bit "payload" > variable. The code currently tries to print it by taking the address > of the variable and passing this pointer to qemu_chr_fe_write(). However, > this only works on little endian hosts where the least significant bits > are stored on the lowest address. To do this in a portable way, we have > to store the value in an uint8_t variable instead. > > Fixes: 5033606780 ("RISC-V HTIF Console") > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> > hw/char/riscv_htif.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/hw/char/riscv_htif.c b/hw/char/riscv_htif.c > index 37d3ccc76b..f96df40124 100644 > --- a/hw/char/riscv_htif.c > +++ b/hw/char/riscv_htif.c > @@ -232,7 +232,8 @@ static void htif_handle_tohost_write(HTIFState *s, uint64_t val_written) > s->tohost = 0; /* clear to indicate we read */ > return; > } else if (cmd == HTIF_CONSOLE_CMD_PUTC) { > - qemu_chr_fe_write(&s->chr, (uint8_t *)&payload, 1); > + uint8_t ch = (uint8_t)payload; > + qemu_chr_fe_write(&s->chr, &ch, 1); > resp = 0x100 | (uint8_t)payload; > } else { > qemu_log("HTIF device %d: unknown command\n", device);
On 21/7/23 11:47, Thomas Huth wrote: > The character that should be printed is stored in the 64 bit "payload" > variable. The code currently tries to print it by taking the address > of the variable and passing this pointer to qemu_chr_fe_write(). However, > this only works on little endian hosts where the least significant bits > are stored on the lowest address. To do this in a portable way, we have > to store the value in an uint8_t variable instead. > > Fixes: 5033606780 ("RISC-V HTIF Console") > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- > hw/char/riscv_htif.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
On Fri, Jul 21, 2023 at 7:48 PM Thomas Huth <thuth@redhat.com> wrote: > > The character that should be printed is stored in the 64 bit "payload" > variable. The code currently tries to print it by taking the address > of the variable and passing this pointer to qemu_chr_fe_write(). However, > this only works on little endian hosts where the least significant bits > are stored on the lowest address. To do this in a portable way, we have > to store the value in an uint8_t variable instead. > > Fixes: 5033606780 ("RISC-V HTIF Console") > Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Alistair > --- > hw/char/riscv_htif.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/hw/char/riscv_htif.c b/hw/char/riscv_htif.c > index 37d3ccc76b..f96df40124 100644 > --- a/hw/char/riscv_htif.c > +++ b/hw/char/riscv_htif.c > @@ -232,7 +232,8 @@ static void htif_handle_tohost_write(HTIFState *s, uint64_t val_written) > s->tohost = 0; /* clear to indicate we read */ > return; > } else if (cmd == HTIF_CONSOLE_CMD_PUTC) { > - qemu_chr_fe_write(&s->chr, (uint8_t *)&payload, 1); > + uint8_t ch = (uint8_t)payload; > + qemu_chr_fe_write(&s->chr, &ch, 1); > resp = 0x100 | (uint8_t)payload; > } else { > qemu_log("HTIF device %d: unknown command\n", device); > -- > 2.39.3 > >
diff --git a/hw/char/riscv_htif.c b/hw/char/riscv_htif.c index 37d3ccc76b..f96df40124 100644 --- a/hw/char/riscv_htif.c +++ b/hw/char/riscv_htif.c @@ -232,7 +232,8 @@ static void htif_handle_tohost_write(HTIFState *s, uint64_t val_written) s->tohost = 0; /* clear to indicate we read */ return; } else if (cmd == HTIF_CONSOLE_CMD_PUTC) { - qemu_chr_fe_write(&s->chr, (uint8_t *)&payload, 1); + uint8_t ch = (uint8_t)payload; + qemu_chr_fe_write(&s->chr, &ch, 1); resp = 0x100 | (uint8_t)payload; } else { qemu_log("HTIF device %d: unknown command\n", device);
The character that should be printed is stored in the 64 bit "payload" variable. The code currently tries to print it by taking the address of the variable and passing this pointer to qemu_chr_fe_write(). However, this only works on little endian hosts where the least significant bits are stored on the lowest address. To do this in a portable way, we have to store the value in an uint8_t variable instead. Fixes: 5033606780 ("RISC-V HTIF Console") Signed-off-by: Thomas Huth <thuth@redhat.com> --- hw/char/riscv_htif.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)