On Thu, Sep 19, 2019 at 10:15 PM Bin Meng <bmeng...@gmail.com> wrote:
>
> On Fri, Sep 20, 2019 at 6:32 AM Alistair Francis
> <alistair.fran...@wdc.com> wrote:
> >
> > Add a property that when set to true QEMU will jump from the ROM code to
> > the start of flash memory instead of DRAM which is the default
> > behaviour.
> >
> > Signed-off-by: Alistair Francis <alistair.fran...@wdc.com>
> > ---
> > hw/riscv/sifive_u.c | 27 +++++++++++++++++++++++++++
> > include/hw/riscv/sifive_u.h | 2 ++
> > 2 files changed, 29 insertions(+)
> >
> > diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
> > index c3949fb316..b7cd3631cd 100644
> > --- a/hw/riscv/sifive_u.c
> > +++ b/hw/riscv/sifive_u.c
> > @@ -373,6 +373,10 @@ static void riscv_sifive_u_init(MachineState *machine)
> > /* dtb: */
> > };
> >
> > + if (s->start_in_flash) {
> > + reset_vec[6] = memmap[SIFIVE_U_FLASH0].base; /* start: .dword
> > FLASH0_BASE */
> > + }
> > +
> > /* copy in the reset vector in little_endian byte order */
> > for (i = 0; i < sizeof(reset_vec) >> 2; i++) {
> > reset_vec[i] = cpu_to_le32(reset_vec[i]);
> > @@ -544,8 +548,31 @@ static void riscv_sifive_u_soc_realize(DeviceState
> > *dev, Error **errp)
> > memmap[SIFIVE_U_GEM_MGMT].base, memmap[SIFIVE_U_GEM_MGMT].size);
> > }
> >
> > +static bool virt_get_start_in_flash(Object *obj, Error **errp)
> > +{
> > + SiFiveUState *s = RISCV_U_MACHINE(obj);
> > +
> > + return s->start_in_flash;
> > +}
> > +
> > +static void virt_set_start_in_flash(Object *obj, bool value, Error **errp)
> > +{
> > + SiFiveUState *s = RISCV_U_MACHINE(obj);
> > +
> > + s->start_in_flash = value;
> > +}
> > +
> > static void riscv_sifive_u_machine_instance_init(Object *obj)
> > {
> > + SiFiveUState *s = RISCV_U_MACHINE(obj);
> > +
> > + s->start_in_flash = false;
> > + object_property_add_bool(obj, "start-in-flash",
> > virt_get_start_in_flash,
> > + virt_set_start_in_flash, NULL);
> > + object_property_set_description(obj, "start-in-flash",
> > + "Set on to tell QEMU's ROM to jump to
> > " \
> > + "flash. Otherwise QEMU will jump to
> > DRAM",
> > + NULL);
> >
> > }
> >
> > diff --git a/include/hw/riscv/sifive_u.h b/include/hw/riscv/sifive_u.h
> > index a921079fbe..2656b43c58 100644
> > --- a/include/hw/riscv/sifive_u.h
> > +++ b/include/hw/riscv/sifive_u.h
> > @@ -57,6 +57,8 @@ typedef struct SiFiveUState {
> >
> > void *fdt;
> > int fdt_size;
> > +
> > + bool start_in_flash;
> > } SiFiveUState;
> >
> > enum {
>
> This patch chose a different way from the one used in patch "[v1,6/6]
> riscv/virt: Jump to pflash if specified":
>
> - this patch uses reset_vec[6] while patch [6/6] defines a variable start_addr
> - this patch adds a "start-in-flash" property to the machine, while
> patch [6/6] tests against drive IF_PFLASH
Yes, we do it differently for the sifive_u board as the sifive_u board
doesn't use pflash so there is no way to know if the user has loaded
anything into the SPI memory.
>
> We should be consistent and I would prefer to use the patch [6/6] way.
> On Unleashed an SPI flash is mounted so we cannot add a PFlash to
> sifive_u machine like what was done on virt machine, so we should test
> IF_MTD instead. Thoughts?
How would we test that?
Right now I am loading the binary in SPI with the -device loader
option. The machine can't really know what is/isn't loaded there.
It's not ideal, but I don't see a nicer way.
Alistair
>
> Regards,
> Bin
