diff options
| author | Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org> | 2024-10-23 13:38:20 +0200 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2024-11-04 16:03:25 -0500 |
| commit | 449dca6ac93afbed1af00b6a29c9729f6cb18c35 (patch) | |
| tree | 04210d38879975815a7ed7950ea8d8502d665d6b /hw/core/machine.c | |
| parent | 6ce12bd29777d41afef859652eaa62b5c964d3f7 (diff) | |
pcie: enable Extended tag field support
>From what I read PCI has 32 transactions, PCI Express devices can handle
256 with Extended tag enabled (spec mentions also larger values but I
lack PCIe knowledge).
QEMU leaves 'Extended tag field' with 0 as value:
Capabilities: [e0] Express (v1) Root Complex Integrated Endpoint, IntMsgNum 0
DevCap: MaxPayload 128 bytes, PhantFunc 0
ExtTag- RBE+ FLReset- TEE-IO-
SBSA ACS has test 824 which checks for PCIe device capabilities. BSA
specification [1] (SBSA is on top of BSA) in section F.3.2 lists
expected values for Device Capabilities Register:
Device Capabilities Register Requirement
Role based error reporting RCEC and RCiEP: Hardwired to 1
Endpoint L0s acceptable latency RCEC and RCiEP: Hardwired to 0
L1 acceptable latency RCEC and RCiEP: Hardwired to 0
Captured slot power limit scale RCEC and RCiEP: Hardwired to 0
Captured slot power limit value RCEC and RCiEP: Hardwired to 0
Max payload size value must be compliant with PCIe spec
Phantom functions RCEC and RCiEP: Recommendation is to
hardwire this bit to 0.
Extended tag field Hardwired to 1
1. https://developer.arm.com/documentation/den0094/c/
This change enables Extended tag field. All versioned platforms should
have it disabled for older versions (tested with Arm/virt).
Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Message-Id: <20241023113820.486017-1-marcin.juszkiewicz@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/core/machine.c')
| -rw-r--r-- | hw/core/machine.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/hw/core/machine.c b/hw/core/machine.c index adaba17eba..8ccc74067a 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -34,7 +34,9 @@ #include "hw/virtio/virtio-iommu.h" #include "audio/audio.h" -GlobalProperty hw_compat_9_1[] = {}; +GlobalProperty hw_compat_9_1[] = { + { TYPE_PCI_DEVICE, "x-pcie-ext-tag", "false" }, +}; const size_t hw_compat_9_1_len = G_N_ELEMENTS(hw_compat_9_1); GlobalProperty hw_compat_9_0[] = { |