[v5] hw/riscv/virt: pflash improvements

[PATCH v5 0/3] hw/riscv/virt: pflash improvements

Sunil V L posted 3 patches 2 days, 7 hours ago

Diff against v4
Download series mbox

Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/20230526121006.76388-1-sunilvl@ventanamicro.com

Maintainers: Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <alistair.francis@wdc.com>, Bin Meng <bin.meng@windriver.com>, Weiwei Li <liweiwei@iscas.ac.cn>, Daniel Henrique Barboza <dbarboza@ventanamicro.com>, Liu Zhiwei <zhiwei_liu@linux.alibaba.com>

docs/system/riscv/virt.rst | 29 ++++++++++++++++++++
hw/riscv/virt.c            | 56 +++++++++++++++-----------------------
2 files changed, 51 insertions(+), 34 deletions(-)

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[PATCH v5 0/3] hw/riscv/virt: pflash improvements

Posted by Sunil V L 2 days, 7 hours ago

This series improves the pflash usage in RISC-V virt machine with solutions to
below issues.

1) Currently the first pflash is reserved for ROM/M-mode firmware code. But S-mode
payload firmware like EDK2 need both pflash devices to have separate code and variable
store so that OS distros can keep the FW code as read-only. 

The issue is reported at
https://salsa.debian.org/qemu-team/edk2/-/commit/c345655a0149f64c5020bfc1e53c619ce60587f6

2) The latest way of using pflash devices in other architectures and libvirt
is by using -blockdev and machine options. However, currently this method is
not working in RISC-V.

With above issues fixed, added documentation on how to use pflash devices
in RISC-V virt machine.

This patch series is based on Alistair's riscv-to-apply.next branch.

Changes since v4:
	1) Updated patch 2 to avoid accessing private field as per feedback from Philippe.
	2) Updated documentation patch to add read-only for ROM usage.
	3) Rebased to latest riscv-to-apply.next branch and updated tags.

Changes since v3:
	1) Converted single patch to a series with a cover letter since there are
	   multiple patches now.
	2) Added a new patch to enable pflash usage via -blockdev option.
	3) Separated the documentation change into new patch and updated the
	   documentation to mention only -blockdev option which seems to be the
	   recommended way of using pflash.

Changes since v2:
	1) Reverted v2 changes and used v1 approach so that pflash0 can be used
	   for code and pflash1 for variable store.
	2) Rebased to latest riscv-to-apply.next branch.
	3) Added documentation for pflash usage.

Changes since v1:
	1) Simplified the fix such that it doesn't break current EDK2.

Sunil V L (3):
  hw/riscv: virt: Assume M-mode FW in pflash0 only when "-bios none"
  riscv/virt: Support using pflash via -blockdev option
  docs/system: riscv: Add pflash usage details

 docs/system/riscv/virt.rst | 29 ++++++++++++++++++++
 hw/riscv/virt.c            | 56 +++++++++++++++-----------------------
 2 files changed, 51 insertions(+), 34 deletions(-)

-- 
2.34.1

Re: [PATCH v5 0/3] hw/riscv/virt: pflash improvements

Posted by Andrea Bolognani 2 days, 7 hours ago

On Fri, May 26, 2023 at 05:40:03PM +0530, Sunil V L wrote:
> This series improves the pflash usage in RISC-V virt machine with solutions to
> below issues.
>
> 1) Currently the first pflash is reserved for ROM/M-mode firmware code. But S-mode
> payload firmware like EDK2 need both pflash devices to have separate code and variable
> store so that OS distros can keep the FW code as read-only.
>
> The issue is reported at
> https://salsa.debian.org/qemu-team/edk2/-/commit/c345655a0149f64c5020bfc1e53c619ce60587f6
>
> 2) The latest way of using pflash devices in other architectures and libvirt
> is by using -blockdev and machine options. However, currently this method is
> not working in RISC-V.
>
> With above issues fixed, added documentation on how to use pflash devices
> in RISC-V virt machine.
>
> This patch series is based on Alistair's riscv-to-apply.next branch.
>
> Changes since v4:
> 	1) Updated patch 2 to avoid accessing private field as per feedback from Philippe.
> 	2) Updated documentation patch to add read-only for ROM usage.
> 	3) Rebased to latest riscv-to-apply.next branch and updated tags.

Still works great :)

Tested-by: Andrea Bolognani <abologna@redhat.com>

-- 
Andrea Bolognani / Red Hat / Virtualization