| Message ID | 20230601045910.18646-4-sunilvl@ventanamicro.com |
|---|---|
| State | New |
| Headers | show |
| Series | hw/riscv/virt: pflash improvements | expand |
On Thu, Jun 1, 2023 at 3:01 PM Sunil V L <sunilvl@ventanamicro.com> wrote: > > pflash devices can be used in virt machine for different > purposes like for ROM code or S-mode FW payload. Add a > section in the documentation on how to use pflash devices > for different purposes. > > Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Alistair > --- > docs/system/riscv/virt.rst | 31 +++++++++++++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > diff --git a/docs/system/riscv/virt.rst b/docs/system/riscv/virt.rst > index 4b16e41d7f..b33f45e5b3 100644 > --- a/docs/system/riscv/virt.rst > +++ b/docs/system/riscv/virt.rst > @@ -53,6 +53,37 @@ with the default OpenSBI firmware image as the -bios. It also supports > the recommended RISC-V bootflow: U-Boot SPL (M-mode) loads OpenSBI fw_dynamic > firmware and U-Boot proper (S-mode), using the standard -bios functionality. > > +Using flash devices > +------------------- > + > +By default, the first flash device (pflash0) is expected to contain > +S-mode firmware code. It can be configured as read-only, with the > +second flash device (pflash1) available to store configuration data. > + > +For example, booting edk2 looks like > + > +.. code-block:: bash > + > + $ qemu-system-riscv64 \ > + -blockdev node-name=pflash0,driver=file,read-only=on,filename=<edk2_code> \ > + -blockdev node-name=pflash1,driver=file,filename=<edk2_vars> \ > + -M virt,pflash0=pflash0,pflash1=pflash1 \ > + ... other args .... > + > +For TCG guests only, it is also possible to boot M-mode firmware from > +the first flash device (pflash0) by additionally passing ``-bios > +none``, as in > + > +.. code-block:: bash > + > + $ qemu-system-riscv64 \ > + -bios none \ > + -blockdev node-name=pflash0,driver=file,read-only=on,filename=<m_mode_code> \ > + -M virt,pflash0=pflash0 \ > + ... other args .... > + > +Firmware images used for pflash must be exactly 32 MiB in size. > + > Machine-specific options > ------------------------ > > -- > 2.34.1 > >
diff --git a/docs/system/riscv/virt.rst b/docs/system/riscv/virt.rst index 4b16e41d7f..b33f45e5b3 100644 --- a/docs/system/riscv/virt.rst +++ b/docs/system/riscv/virt.rst @@ -53,6 +53,37 @@ with the default OpenSBI firmware image as the -bios. It also supports the recommended RISC-V bootflow: U-Boot SPL (M-mode) loads OpenSBI fw_dynamic firmware and U-Boot proper (S-mode), using the standard -bios functionality. +Using flash devices +------------------- + +By default, the first flash device (pflash0) is expected to contain +S-mode firmware code. It can be configured as read-only, with the +second flash device (pflash1) available to store configuration data. + +For example, booting edk2 looks like + +.. code-block:: bash + + $ qemu-system-riscv64 \ + -blockdev node-name=pflash0,driver=file,read-only=on,filename=<edk2_code> \ + -blockdev node-name=pflash1,driver=file,filename=<edk2_vars> \ + -M virt,pflash0=pflash0,pflash1=pflash1 \ + ... other args .... + +For TCG guests only, it is also possible to boot M-mode firmware from +the first flash device (pflash0) by additionally passing ``-bios +none``, as in + +.. code-block:: bash + + $ qemu-system-riscv64 \ + -bios none \ + -blockdev node-name=pflash0,driver=file,read-only=on,filename=<m_mode_code> \ + -M virt,pflash0=pflash0 \ + ... other args .... + +Firmware images used for pflash must be exactly 32 MiB in size. + Machine-specific options ------------------------